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FIELD OF THE INVENTION
[0001] The invention relates to a process for making ethylene copolymers. The process, which uses a Ziegler-Natta catalyst prepared from the reaction of a transition metal compound with a mixture of an organomagnesium compound and a silicon-containing compound, is valuable for producing copolymers of ethylene and vinylsilanes.
BACKGROUND OF THE INVENTION
[0002] Ziegler-Natta catalysts are a mainstay for polyolefin manufacture. Much research has been done since their inception and there are many types of Ziegler-Natta catalysts. One useful Ziegler-Natta catalyst is disclosed in U.S. Pat. No. 4,464,518. It is made from the reaction product of a halogen-containing vanadium or titanium compound with a mixture of an organomagnesium compound and a silicon-containing compound. The catalyst and cocatalyst are described as being useful for ethylene polymerizations and ethylene copolymerizations with alpha-olefins such as propylene, 1-butene, 1-hexene or 1-octene. There is no indication that this catalyst would be effective for the copolymerization of ethylene with other types of olefins.
[0003] Silicon compounds have been used as donors with Ziegler-Natta catalysts. M. Harkonen, J. V. Seppala and T. Vaananen, Makromol. Chem. 192 (1991) 721 report that external donors markedly increase the sterospecificity and usually decrease the activity of Ziegler-Natta catalysts and that the generally accepted view of the role of the donor is a selective deactivation of active centers. Y. V. Kissin, J. Polym. Sci. Part A: Polym. Chem., 33 (1995) 227, reports a series of ethylene-hexene copolymerization experiments with varying amounts of diphenyidimethoxysilane. Increasing levels of silane decreased the 1-hexene incorporation and they concluded that the silanes poison different catalytic centers to different degrees.
[0004] There are many other instances of the use of low levels of silicon compounds as electron donors to modify a Ziegler-Natta catalyst. See, e.g., U.S. Pat. Nos. 6,559,250; 6,359,667; 6,362,124; 6,337,377; 5,595,827; and 4,900,706. The silicon compounds are often alkoxysilanes and can include vinylalkoxysilanes. The vinyl group is not required for the alkoxysilane to act as a catalyst donor. The silicon compounds are not used as comonomers and there is no indication that there could be any incorporation into the polymer chain.
[0005] U.S. Pat. No. 5,275,993 teaches a solid component for a Ziegler-Natta catalyst and the modification of the solid component with several components other than the essential titanium, magnesium and halogen components. Electron donors, silicon compounds, vinylsilane compounds and organoaluminum compounds are listed as possible modifiers. The vinylsilane is not used as a comonomer and there is no indication that there could be any incorporation into the polymer chain.
[0006] Copolymers of ethylene with vinylsilanes are known. U.S. Pat. Nos. 3,225,018 and 3,392,156 disclose free-radical copolymerizations under high pressure and temperature in the presence of a free-radical initiator. U.S. Pat. No. 3,225,018 teaches that the copolymerizations are generally conducted at pressures of 69 to 690 MPa and that the resultant copolymers can be crosslinked. U.S. Pat. No. 3,392,156 teaches reaction pressures of 103 to 310 MPa and that the copolymers have improved stress-crack resistance.
[0007] Another approach has been to graft vinylsilanes to polyolefins by heating them together in the presence of radical initiators such as peroxides. See, e.g., U.S. Pat. Nos. 6,465,107 and 4,902,460. These methods are difficult, have certain process hazards, can cause degradation of the polyolefin chain, and have limited flexibility to make a variety of polymers.
[0008] Incorporating silane functionality into polyolefins can impart crosslinkability for polyolefin products with improved strength and stiffness. It is also valuable for modifying flow properties or for bonding polyolefins to polysiloxanes, polyethers, polyurethanes, and other functionalized polymers. Despite the utility of copolymers of ethylene with vinylsilanes, it is apparently difficult to prepare these copolymers as evidenced by so few examples in the literature. The reported processes are limited and require very high pressure. Operating at such high pressure requires special equipment. There is a need for alternative processes to make ethylene-vinylsilane copolymers, preferably ones that work at relatively low pressures.
SUMMARY OF THE INVENTION
[0009] The invention is a process for copolymerizing ethylene with a vinylsilane. The process comprises conducting the copolymerization in the presence of a Ziegler-Natta catalyst and a cocatalyst. The Ziegler-Natta catalyst comprises the reaction product of a Group 4-6 halogen-containing transition metal compound with a mixture of an organomagnesium compound and a silicon-containing compound. We surprisingly found that the catalyst and cocatalyst enable the copolymerization of ethylene with vinylsilanes at ordinary temperatures and pressures.
DETAILED DESCRIPTION OF THE INVENTION
[0010] In the process of the invention, ethylene is copolymerized with a vinylsilane in the presence of a Ziegler-Natta catalyst and a cocatalyst. The Ziegler-Natta catalyst comprises the reaction product of a Group 4-6 halogen-containing transition metal compound with a mixture of an organomagnesium compound and a silicon-containing compound. Preferably, the transition metal is Ti or V and more preferably the transition metal is Ti. Suitable halogen-containing transition metal compounds include TiCl 4 , TiCl(OCH 2 CH 3 ) 3 , VOCl 3 , VCl 4 and the like.
[0011] The organomagnesium compound is preferably a Grignard reagent, more preferably an alkylmagnesium halide and most preferably an alkylmagnesium chloride. Suitable organomagnesium compounds include diethylmagnesium, ethylmagnesium bromide, butylmagnesium chloride and the like. The organomagnesium compound is mixed with a silicon-containing compound. Preferably, the silicon-containing compound is a hydroxysilane or a polyhydrosiloxane. Suitable hydroxysilanes include trimethylhydroxysilane, methyldiphenylhydroxysilane, dipropyldihydroxysilane, butyltrihydroxysilane and the like. More preferably, the silicon-containing compound is a polyhydrosiloxane. Suitable polyhydrosiloxanes include polymethylhydrosiloxane, tetramethylcyclotetrasiloxane, dihydropolysiloxane and the like. Most preferably, the silicon-containing compound is polymethylhydrosiloxane.
[0012] The mixing of the organomagnesium compound with the silicon-containing compound is preferably done in a solvent and preferably at a time and temperature to enable a reaction to take place between them. Tetrahydrofuran is a convenient solvent but other solvents and combinations of solvents may be used. The time and temperature can be varied. Typically, the reaction is complete after several hours at room temperature, but the reaction can be performed in a shorter time at a higher temperature. One hour in refluxing tetrahydrofuran is convenient and gives good results.
[0013] Preferably, the mixture of the organomagnesium compound with the silicon-containing compound is pre-reacted with a mixture of an aluminum compound and an alcohol prior to combining with the halogen-containing transition metal compound. Suitable aluminum compounds include alkyl aluminum halides such as diethyl aluminum chloride, diisobutyl aluminum chloride, ethyl aluminum dichloride and the like. Suitable alcohols include straight chain aliphatic alcohols such as methanol or n-hexanol, branched chain aliphatic alcohols such as isopropanol or 2-ethylhexanol or cyclic alcohols such as cyclohexanol or 3-methylcyclopentanol and mixtures thereof. Preferably, the alcohol is a mixture of a straight chain aliphatic alcohol with either a branched chain aliphatic alcohol or a cyclic aliphatic alcohol.
[0014] Preferred Ziegler-Natta catalysts and methods for their preparation are described in U.S. Pat. No. 4,464,518, which is incorporated herein by reference.
[0015] The cocatalyst is selected from the group consisting of trialkyl aluminum, dialkyl aluminum halide, and alkyl aluminum dihalide. Suitable cocatalysts include triethyl aluminum, triisobutyl aluminum, diethyl aluminum chloride and butyl aluminum dichloride and the like and mixtures thereof.
[0016] Ethylene is copolymerized with a vinylsilane. Preferably, the vinylsilane is a vinyltrialkylsilane such as vinyltrimethylsilane, a vinylalkylalkoxysilane such as vinylmethyldiethoxysilane or vinyldimethylethoxysilane or more preferably, a vinyltrialkoxysilane such as vinyltriethoxysilane or vinyltrimethoxysilane.
[0017] Preferably, the vinylsilane has the general structure:
in which each R 1 is independently selected from hydrogen, halogen, and C 1 -C 20 hydrocarbyl and each R is independently selected from C 1 -C 20 hydrocarbyl. More preferably, R 1 is hydrogen and each R is independently selected from C 1 -C 6 hydrocarbyl.
[0019] Preferably the vinylsilane is added at a level of from about 50 micromoles to about 5,000 micromoles per gram of polyolefin produced, more preferably from about 100 micromoles to about 3,000 micromoles per gram of polyolefin produced.
[0020] Optionally, ethylene and the vinylsilane are copolymerized with a third olefin. Preferred third olefins are propylene, 1-butene, 1-pentene, 1-hexene, 1-octene and mixtures thereof.
[0021] While there are many ways to practice the ethylene copolymerization process of the invention, the process is preferably a slurry or gas-phase process.
[0022] The polymerizations can be performed over a wide temperature range, such as about −30° C. to about 280° C. A more preferred range is from about 20° C. to about 180° C.; most preferred is the range from about 30° C. to about 100° C. Olefin partial pressures normally range from about 0.1 MPa to about 350 MPa. More preferred is the range from about 0.3 MPa to about 25 MPa. Most preferred is the range from about 0.5 MPa to about 4 MPa. The ability to operate under such mild conditions of temperature and pressure obviates the need for special equipment.
[0023] The following examples merely illustrate the invention. Those skilled in the art will recognize many variations that are within the spirit of the invention and scope of the claims.
Catalyst A
[0024] Catalyst A is prepared by reacting n-butylmagnesium chloride with trimethylsilyl-terminated polymethylhydrosiloxane and reacting that product with the reaction product from a mixture of ethanol, isopropanol and diethyl aluminum chloride. This subsequent product is then reacted with titanium tetrachloride to afford catalyst A. The general procedure is described in Example 3 of U.S. Pat. No. 4,464,518. The solid catalyst is not collected but used as a hexane slurry. The hexane slurry contains about 1.95×10 −3 g Ti in 1.0 mL. A portion (1.0 mL) of this hexane slurry is further diluted to 30 mL with mineral oil and used in polymerizations.
EXAMPLE 1
Copolymerization of Ethylene and Vinyltriethoxysilane
[0025] A 20 mL steel vessel equipped with a 15 mL glass liner is charged with 5.0 mL heptane, 0.2 mL of a mineral oil slurry of catalyst A (approximate titanium content=1.3×10 −5 g Ti), 0.1 mL of a solution of 1.56 M triethyl aluminum in heptane, and 0.1 mL of 0.47 M vinyltriethoxysilane (VTEOS) in heptane (47 micromoles vinyltriethoxysilane). The vessel is heated to 80° C. Hydrogen is added to pressurize the vessel to 0.07 MPa and ethylene fed to the vessel to maintain 1.4 MPa. The polymerization proceeds for thirty minutes. The reactor is vented and methanol added. The solvent is evaporated and the polyolefin is collected and dried prior to testing. The reaction yields 0.33 g polyolefin. The weight average (M w ) molecular weight and number average (M n ) molecular weight of the polymer are measured by gel permeation chromatography (GPC) using 1,3,5-trichlorobenzene at 145° C. to be 1.2×10 6 g/mole and 1.2×10 5 g/mole. The melting point and heat of fusion were determined by differential scanning calorimetry to be 133.3 ° C. and 152 J/g.
EXAMPLES 2-5 AND COMPARATIVE EXAMPLES 6-7
[0026] The polymerization procedure of Example 1 is generally followed except the amount of vinyltriethoxysilane is varied. The results are summarized in Table 1.
TABLE 1 Polymerizations Mw Mn Melting Heat of VTEOS g (× 10 6 ) (× 10 5 ) Point Fusion Ex. (micromoles) polyolefin g/mole g/mole ° C. J/g 1 47 0.33 1.2 1.2 133.3 152 2 47 0.31 133.9 148 3 240 0.15 0.43 0.39 129.9 104 4 240 0.13 130.3 101 5 470 0.18 119.2 17 C6 0 1.5 0.54 0.62 135.6 184 C7 0 1.5 0.45 0.42 134.1 171
[0027] As the amount of vinyltriethoxysilane (VTEOS) is increased, the melting point decreases and the heat of fusion decreases. This indicates good incorporation of the vinyltriethoxysilane into the ethylene copolymer. The good agreement between Examples 1 and 2 and between Examples 3 and 4 shows the reproducibility of the process. Comparative Examples 6 and 7 have no VTEOS and therefore the polyethylene has a high melting point and high heat of fusion.
[0028] The preceding examples are meant only as illustrations. The following claims define the invention. | A process for copolymerizing ethylene with vinylsilanes is disclosed. The process uses a Ziegler-Natta catalyst and cocatalyst wherein the Ziegler-Natta catalyst is prepared from a Group 4-6 halogen-containing transition metal and a mixture of an organomagnesium compound and a silicon-containing compound. Silane-functionalized polyolefins produced using the process can be crosslinkable and can be used to bond polyolefins to polysiloxanes or other functionalized polymers. | 2 |
BACKGROUND OF THE INVENTION
[0001] Ion implanters are commonly used in the production of semiconductor wafers. An ion source is used to create an ion beam, which is then directed toward the wafer. As the ions strike the wafer, they dope a particular region of the wafer. The configuration of doped regions defines their functionality, and through the use of conductive interconnects, these wafers can be transformed into complex circuits.
[0002] A block diagram of a representative ion implanter 100 is shown in FIG. 1 . An ion source 110 generates ions of a desired species. In some embodiments, these species are atomic ions, which may be best suited for high implant energies. In other embodiments, these species are molecular ions, which may be better suited for low implant energies. These ions are formed into a beam, which then passes through a source filter 120 . The source filter is preferably located near the ion source. The ions within the beam are accelerated/decelerated in column 130 to the desired energy level. A mass analyzer magnet 140 , having an aperture 145 , is used to remove unwanted components from the ion beam, resulting in an ion beam 150 having the desired energy and mass characteristics passing through resolving aperture 145 .
[0003] In certain embodiments, the ion beam 150 is a spot beam. In this scenario, the ion beam passes through a scanner 160 , which can be either an electrostatic or magnetic scanner, which deflects the ion beam 150 to produce a scanned beam 155 - 157 . In certain embodiments, the scanner 160 comprises separated scan plates in communication with a scan generator. The scan generator creates a scan voltage waveform, such as a sine, sawtooth or triangle waveform having amplitude and frequency components, which is applied to the scan plates. In a preferred embodiment, the scanning waveform is typically very close to being a triangle wave (constant slope), so as to leave the scanned beam at every position for nearly the same amount of time. Deviations from the triangle are used to make the beam uniform. The resultant electric field causes the ion beam to diverge as shown in FIG. 1 .
[0004] In an alternate embodiment, the ion beam 150 is a ribbon beam. In such an embodiment, there is no need for a scanner, so the ribbon beam is already properly shaped.
[0005] An angle corrector 170 is adapted to deflect the divergent ion beamlets 155 - 157 into a set of beamlets having substantially parallel trajectories. Preferably, the angle corrector 170 comprises a magnet coil and magnetic pole pieces that are spaced apart to form a gap, through which the ion beamlets pass. The coil is energized so as to create a magnetic field within the gap, which deflects the ion beamlets in accordance with the strength and direction of the applied magnetic field. The magnetic field is adjusted by varying the current through the magnet coil. Alternatively, other structures, such as parallelizing lenses, can also be utilized to perform this function.
[0006] Following the angle corrector 170 , the scanned beam is targeted toward the workpiece 175 . The workpiece is attached to a workpiece support. The workpiece support provides a variety of degrees of movement.
[0007] The workpiece support is used to both hold the wafer in position, and to orient the wafer so as to be properly implanted by the ion beam. To effectively hold the wafer in place, most workpiece supports typically use a circular surface on which the workpiece rests, known as a platen. Often, the platen uses electrostatic force to hold the workpiece in position. By creating a strong electrostatic force on the platen, also known as the electrostatic chuck, the workpiece or wafer can be held in place without any mechanical fastening devices. This minimizes contamination and also improves cycle time, since the wafer does not need to be unfastened after it has been implanted. These chucks typically use one of two types of force to hold the wafer in place: coulombic or Johnson-Rahbeck force.
[0008] The workpiece support typically is capable of moving the workpiece in one or more directions. For example, in ion implantation, the ion beam is typically a scanned or ribbon beam, having a width much greater than its height. Assume that the width of the beam is defined as the x axis, the height of the beam is defined as the y axis, and the path of travel of the beam is defined as the z axis. The width of the beam is typically wider than the workpiece, such that the workpiece does not have to be moved in the x direction. However, it is common to move the workpiece along the y axis to expose the entire workpiece to the beam.
[0009] Temperature, in particular, the temperature of the substrate onto which a particular ion or species is being implanted, plays an important role in ion implantation. While many ion implants are done at room temperature, there are benefits to performing implantation at other temperatures.
[0010] For example, low temperature implantation is known to reduce the number of end of range (EOR) defects. When ions are implanted into a substrate, they penetrate to a certain depth. Within this region, the implanted ions serve to change the normal crystalline structure of the substrate, such as silicon, into an amorphous structure. Those depths of the substrate that are not reached by the ions remain crystalline in structure. Therefore, there exists an interface between these two regions, known as the amorphous/crystalline interface. Near this interface, at the lower portion of the amorphous region, is an area that contains a higher density of interstitials. When the substrate is annealed after implantation to activate the dopant and to recrystallize this region, residual non-homogeneities cause residual defects. These defects are called the end of range (EOR) defects. These defects can take the form of dislocations and stacking faults.
[0011] These EOR defects, when present in the source or drain regions, cause junction leakage, which ultimately affects the performance of the final semiconductor component. As noted above, low temperature ion implantation has been shown to reduce the generation of EOR defects, thus improving component performance. This feature is especially important in ultrashallow junctions, where the depth of the source and drain regions is very small.
[0012] Alternatively, ion implanting or doping into substrates maintained at elevated temperatures (higher than room temperature) can also have benefits. Amorphization of crystalline materials that occurs with implant can be reduced. This may be preferable in applications where ions are being implanted into epitaxially grown substrates. Amorphization tends to destroy inherent properties of doped epi-substrates. Higher temperature implants are also beneficial when the implant dose is less than amorphization threshold. The overall residual damage in the substrate is reduced when such an implant is performed at elevated temperatures. For such low dose implants, heated implanted can also result in lower sheet resistance because of better dopant activation and reduced damage results in smaller amount of ‘transient diffusion’, which can degrade resistivity.
[0013] However, each of these temperature implantation modes also has disadvantages. A method of implantation which maximizes the advantages of each temperature implant, while minimizing the disadvantages would be very beneficial.
SUMMARY OF THE INVENTION
[0014] The problems of the prior art are overcome by the ion implantation method described in the present disclosure. The disclosure provides a method for ion implantation that includes modulating the temperature of the substrate during the process. This modulation affects the properties of the substrate, and can be used to minimize EOR defects, selectively segregate and diffuse out secondary dopants, maximize or minimize the amorphous region, and vary other semiconductor parameters. In one particular embodiment, a combination of temperature modulated ion implants are used. Ion implantation at higher temperatures is used in sequence with regular baseline processing and with ion implantation at cold temperatures. The temperature modulation could be at the beginning or at the end of the process to alleviate the detrimental secondary dopant effects.
BRIEF DESCRIPTION OF FIGURES
[0015] FIG. 1 represents a traditional ion implanter;
[0016] FIG. 2 represents a graph showing ion concentrations after BF 2 has been implanted into a substrate;
[0017] FIG. 3 represents a graph showing ion concentrations after BF 2 has been implanted into a substrate at cold temperature;
[0018] FIG. 4 represents an exemplary temperature profile that can be used according to one embodiment;
[0019] FIG. 5 represents a graph showing ion concentrations after BF 2 has been implanted into a substrate using the temperature profile shown in FIG. 4 ; and
[0020] FIGS. 6 a - e represent various temperature profiles that can be used according to other embodiments.
DETAILED DESCRIPTION OF THE INVENTION
[0021] As stated above, temperature plays an important role in ion implantation. While many ion implants are done at or close to room temperature, there are benefits to performing implantation at high temperature or low temperature. For example, cryogenic ion implantation is beneficial in a number of applications, for example, in creating ultrashallow junctions in a crystalline silicon wafer. High temperature is useful when implanting germanium epilayers to reduce amorphization.
[0022] The present description discloses various embodiments in which the use of a plurality of temperatures during implant improves the quality and performance of the underlying semiconductor device. It is obvious to one skilled in the art that the following represents only a fraction of the possible uses of the disclosed method and other uses are contemplated and within the scope of the disclosure.
[0023] Ultrashallow junctions (USJ) are increasingly important in current semiconductor processing. Previously, atomic ions, such as B | , were used to dope a region of a substrate. However, for shallow implantations, the required energy levels of the beam are lower. These lower energy level result in space-charge effects in the ion beam. To counteract these effects, heavier molecular ions are used, which do not penetrate the substrate as deeply due to the increased nuclear collisions with the lattice. Since higher energy levels can be used, space charge effects are minimized. Thus, instead of implanting an atomic ion such as B+, a molecular ion, such as BF 2 + , BF 3 + , CBH, B 6 H 10 or PH 3 , is used.
[0024] While these molecular ions indeed perform ionization at a more shallow level, there are several drawbacks. The use of these molecules leads to secondary dopants being implanted. For example, when BF 2 + is implanted, this molecule can separate upon collision with the substrate, thereby creating secondary dopants, such as BF + , B + and F − . Similar results occur when other molecular ions are used. For example, PH 3 can create secondary ions that include H − . These secondary dopants can have detrimental effects. For example, fluorine, which is highly reactive, corrodes contact metals. In other cases, fluorine and hydrogen form complexes that reduce the activation efficiency of the desired dopant. Additionally, fluorine and hydrogen play a role in the strain relaxation of the junction. Specifically, when a SiGe source/drain is implanted with BF 2 , it will lose strain as a result of the amorphization and the incorporation of fluorine ions. Finally, because of the competition between the desired dopants and the secondary dopants, such as fluorine and hydrogen, the segregation and diffusion tendencies are altered. This, in some cases, leads to higher resistivity.
[0025] The effects of these secondary dopants are illustrated in FIG. 2 . In this Figure, a substrate has been implanted with BF 2 + . As the molecular ions collide with the structure within the substrate, the molecular ions break down as described above. This graph shows the two key dopants that result from this implantation, boron and fluorine. The vertical axis signifies the concentration of each dopant, while the horizontal axis signifies the depth within the substrate. In other words, the y-axis represents the top surface of the substrate, and the substrate depth increases moving right along the x-axis. This graph has two lines; the first solid line represents the desired dopant, boron. As is expected, the concentration of boron approximates a bell shaped curve with its peak below the top surface of the substrate. The second dashed line represents the secondary dopant, fluorine. Unlike boron, the fluorine ions are concentrated in two specific areas. At the upper left of the graph, a first spike in fluorine concentration occurs near the surface of the substrate, where there are known to be many defects in the crystalline structure of the silicon. The second peak occurs much deeper in the substrate. This peak corresponds to the region where EOR defects are found in the substrate. In this case, the fluorine ions are said to “decorate” the EOR defect. The fluorine ions are attracted to these locations due to the number of defects in the structure, which creates more interstitials, which the fluorine ions then occupy.
[0026] As described above, cold ion implantation is known to reduce the occurrence of EOR defects and is commonly used for USJ fabrication. At the colder temperature, such as less than 0° C., and preferably between −10° C. and −100° C., the amorphization quality and thickness improves and therefore EOR defects are reduced.
[0027] FIG. 3 shows the concentration of boron and fluorine ions in a substrate following cold ion implantation. Note that the boron concentration curve is unaffected by the change in temperature. However, the fluorine ion distribution has been greatly affected. As expected, there are few fluorine ions located deep within the substrate, as the EOR defects have been nearly eliminated by the cold temperature implant. This reduces device leakage, which is very advantageous. However, the concentration of fluorine ions near the surface of the substrate increased significantly. Since the fluorine ions are attracted to defects in the substrate, they now aggregate at the surface, since this is the location having the greatest number of defects.
[0028] Unfortunately, fluorine, especially at or near the surface of the substrate is detrimental to metal contact integration during the integrated circuit fabrication sequence. Since fluorine is highly corrosive, it corrodes the contact metals. Therefore, while the cold implant increased the device performance, it adversely affected the device reliability. Furthermore, the corrosion of metals by the fluorine leads to an increase in the resistance of the metals, which also degrades device performance.
[0029] In one embodiment, the temperature at which the ion implantation is performed is changed from low to high during the process. FIG. 4 represents a graph showing dosage, implant time and temperature. Line 100 represents the total dosage applied to the substrate. Line 110 represents the temperature of the platen during the implant, which indirectly controls the temperature of the substrate itself. The vertical axis on the right shows the temperature scale used in this embodiment. In this embodiment, the platen, and therefore the substrate, are cooled to a sufficiently cold temperature, such as −60° C. A portion of the ion implant process is then performed at this temperature. As described above, this temperature improves the amorphization of the substrate and minimizes the number of EOR defects. At a point in the process, such as 75% complete, the temperature of the platen, and therefore the substrate, is increased to a higher temperature, such as 300° C. At this temperature, the trapped fluorine ions, which aggregated at the surface, are able to diffuse out of the substrate and into the ambient environment, thereby significantly reducing the fluorine remaining within the substrate. While FIG. 4 shows a higher temperature of 300° C., this is not a requirement of the disclosure. For example, gasses, such as hydrogen and fluorine, show enhanced diffusion at temperature much lower than 300° C., such as 100° C. or less.
[0030] FIG. 5 represents a graph of the concentration of boron and fluorine ions in a substrate implanted using the temperature profile shown in FIG. 4 . Again, the boron concentration is minimally affected by the change in temperature. However, the fluorine concentration is significantly altered. At increased depth, the fluorine concentration closely resembles that shown in FIG. 3 . However, at shallow depths, near the substrate surface, the fluorine profile is very different, due to the diffusion of fluorine into the ambient environment. Since the rate of diffusion is related to the distance from the substrate surface, the fluorine concentration increases slightly as the depth increases, then decreases again as it follows the profile from FIG. 3 . This profile has the advantages of cold temperature implantation (i.e. better amorphization, limited EOR defects) without the drawback of increased surface fluorine concentration.
[0031] While FIG. 4 shows a constant ramp between the cold temperature and the hot temperature, the disclosure is not limited to this configuration. For example, the temperature may be ramped during the entire implant process. Alternatively, the change in temperature may be more abrupt (i.e. a greater slope for Line 110 ), or more gradual (i.e. reduced slope for line 110 ).
[0032] The concept of using a varying temperature profile during ion implantation has additional applications. For example, in another embodiment, hot ion implantation is performed first, followed by a lower temperature implant. This combination is useful if it is desirable to minimize amorphous creation. One example is the doping/implantation of source and drain regions of modern ICs. Modern source and drain regions (S/D) in transistors are grown epitaxially. During the epi-growth, these regions are doped in-situ within the epitaxial process. P-MOSFETS have germanium doped S/D and N-MOSFETS have carbon doped S/D. This is to enable a strain within the doped lattice. This induced strain, which is due to mismatched atom (Si—Ge—C) sizes and bond lengths, exerts a stress in the channels of the transistors. This stress enhances mobility of carriers and hence the performance of transistors. The S/D regions need additional doping to reduce resistivity. During these implants, minimum damage of the Ge− or C-doped S/D region is preferable so as to maintain the stress in those areas. In such a case, an elevated/higher temperature implant is useful as there is very little amorphization of the implanted area. Furthermore, if a portion (towards the tail end of the implant) is performed at cold temperatures, the surface of the substrates is less defective. Cold implants inherently create fewer defects at the surface. This reduces the probability of defect formation during silicide or contact formation during subsequent processing of the ICs. While the above example described the benefits with epitaxially grown silicon, similar benefits are realized with other materials, such as polysilicon, materials with high dielectric constants (HiK materials), metals, and dielectrics.
[0033] Other applications requiring varied temperature profiles during ion implantation are also within the scope of the disclosure. For example, temperature profiles, such as those shown in FIGS. 6 a - e , can also be used in certain applications. These profiles include step functions, parabolic and inverse parabolic curves, hyperbolic curves, sinusoidal waves and ramp functions.
[0034] The temperature modulation described herein can be performed using a plurality of methods. In one embodiment, the ion implantation process is separated into two or more independent implantation processes. For example, the profile shown in FIG. 4 may be achieved by implanting the substrate using conventional cold implantation techniques for a portion of the cycle. The process is then suspended and resumed using conventional hot implantation techniques. This method results in a discontinuous temperature profile, and also added additional time between the two temperature implants.
[0035] A second method of modulating the temperature of the substrate is through temperature control of the platen on which the substrate rests. In one embodiment, conduits exist within the platen, which can be used to pass fluids, either gas or liquid, through the platen. Depending on the type of fluid and its temperature, this action can cause the platen to be cooled or heated. For example, during the implant shown in FIG. 4 , a refrigerant, such as liquid nitrogen, can be passed through the conduit during the first portion of the implant process. The temperature ramp can be achieved by allowing the heat from implant to warm the substrate and the platen. A second fluid, such as water can then be passed through the platen to maintain its maximum temperature.
[0036] A third method involves the use of an external heating device, such as an IR lamp or laser, to increase the temperature of the platen. The heating can also be achieved through a resistive heating device embedded in the platen that when powered heats the platen and hence the wafer substrate. The heating could also be alternatively done using an inductively coupled heating device. In this scenario, the refrigerant is passed through the platen during the first portion of the implant as described above. However, the temperature increase is achieved by enabling a heating device to warm the surface of the substrate. Once the heating device is enabled, the fluid flow through the platen is stopped.
[0037] In another embodiment, the heating device and the refrigerant are used concurrently to create the desired temperature gradient. For example, for a steep temperature gradient, the heating device is enabled and the fluid flow through platen is ceased. For a more gradual temperature gradient, the heating device is enabled and the fluid flow through the platen continues at the same or a controlled changing rate. | A method for ion implantation is disclosed which includes modulating the temperature of the substrate during the implant process. This modulation affects the properties of the substrate, and can be used to minimize EOR defects, selectively segregate and diffuse out secondary dopants, maximize or minimize the amorphous region, and vary other semiconductor parameters. In one particular embodiment, a combination of temperature modulated ion implants are used. Ion implantation at higher temperatures is used in sequence with regular baseline processing and with ion implantation at cold temperatures. The temperature modulation could be at the beginning or at the end of the process to alleviate the detrimental secondary dopant effects. | 7 |
This application claims the benefit of priority to U.S. provisional application having Ser. No. 61/541,305 filed on Sep. 30, 2011, which is incorporated by reference herein in its entirety.
FIELD OF THE INVENTION
The field of the invention is light redirection technologies.
BACKGROUND
Core daylight illumination apparatus systems for buildings are intended to collect, concentrate and direct sunlight from the exterior of the building to internal workspaces for the purposes of replacing a portion of the normally required electrically powered lighting and of improving lighting quality within those workspaces. Widespread use of such systems in commercial workspaces could significantly reduce energy consumption and greenhouse gas emissions. To foster widespread usage, the building core daylight illumination systems must be cost effective, robust, and compatible with common commercial building design and construction practices.
Previous work on building daylight illumination has not been successful for a number of reasons. Passive daylighting efforts including skylights, vertical light pipes, and other methods of directing non-concentrated or untracked sunlight fail to meet commercial illumination standards over a practical area or during a reasonable percentage of the year and do not provide significant power savings. European Patent application no. 1174658, entitled “Light Carrier System for Natural Light”, by Guzzini, discloses a basic apparatus which collects lights and passes it to the interior of the building through a diffuser. U.S. Pat. No. 6,299,317, “Method and apparatus for a passive solar day lighting apparatus system” by Ravi Gorthala has a Fresnel component, but a “passive” system of light transportation into the building. The collected light would not, therefore, be expected to travel efficiently any distance once inside the building envelope. Control of light distribution is also problematic due to the wide range of angles of light entering the building.
Previous active daylighting, herein referred to as “sunlighting”, efforts also have significant limitations that affect system cost or life cycle. Designs that include an optical fiber mounted such that it moves with the tracking optics are limited by the resistance caused by the bulky array of moving fiber. Accurate tracking in those cases is costly to provide. One such patent is U.S. Pat. No. 7,295,372 to Parans Daylight discloses a system involving a convex and concave lens to focus sunlight onto transmitting fibers. U.S. Pat. No. 7,813,061, also to Parans Daylight, discloses light focusing lenses which are mobile via ball joints and mobile frames that move independently to change the direction of the lenses. The light collecting element and optical fibers receiving the collected light must also move with the apparatus, which creates problems in keeping the light collecting element aligned to collect sunlight efficiently, and leads to lost light as the optical fiber flexes.
Generally, designs that utilize long optical fibers from the collector to the lighting fixture are further limited by the properties of the optical fiber over long distances, which distances cause significant light losses due to bulk absorption and noticeable color spectrum shifts.
Although there are several patents and patent publications pertaining to the concept of concentrating sunlight, or suggesting moving to track the sun, no solutions are offered for a whole apparatus system to make sunlight illumination work in a real context. U.S. Pat. No. 5,169,456 discloses the mechanical aspect of a weather protected “two-axis solar collector mechanism”. No contemplation is made of the necessary optical components of this mechanism, apart from the prediction that a Fresnel lens could be used.
Externally mounted lighting systems have been provided in Vancouver, Canada, using adaptive butterfly arrays of mirrors (United States Patent Publication 20100254010 and U.S. Pat. No. 8,000,014) and parabolic mirrors. Such systems have been able to deliver adequate luminous flux to the interior of the buildings they serve, but the physical aspects of these building “add-ons” are considerable, as they project up to four feet from the buildings' original exterior wall.
The extrinsic materials described herein (European Patent Application No. 1174659, U.S. Pat. Nos. 6,299,317, 7,295,372, 7,813,061, 5,169,456 and 8,000,014, and United States Patent Application Publication 20100254010) and U.S. Provisional Application Ser. No. 61/541,305 are incorporated by reference in their entirety. Where a definition or use of a term in an incorporated reference is inconsistent or contrary to the definition of that term provided herein, the definition of that term provided herein applies and the definition of that term in the reference does not apply.
The related art discloses solutions that have cost and performance issues related to relying on optical fiber to transport light over long distances, requiring high tracking accuracy required to minimize fiber diameter, and having reduced tracking mechanism accuracy limitations when needing to flex fiber. Thus, an improved manifestation of a building core sunlight illumination apparatus system that is more effective in terms of total cost per delivered lumen-hour, quality of delivered light, life cycle and suitability to inclusion in new commercial building construction or renovation is needed.
Unless the context dictates the contrary, all ranges set forth herein should be interpreted as being inclusive of their endpoints, and open-ended ranges should be interpreted to include commercially practical values. Similarly, all lists of values should be considered as inclusive of intermediate values unless the context indicates the contrary.
SUMMARY OF THE INVENTION
The inventive subject matter provides apparatus, systems and methods in which one can construct an opto-mechanical joint that redirects light from a rotatable concentrating element to a fixed location. One aspect of the inventive subject matter includes a joint assembly comprising a light concentrating element mounted on a rotatable frame assembly. The concentrating element can be rotated about an azimuth axis or tilted around an altitude axis to ensure the concentrating element tracks a light source, the sun for example. The concentrating element can include a lens or non-imaging device that concentrates or converges light toward a fixed location. The joint assembly can further include a series of reflective surfaces that redirect the converging light to a fixed location relative to the axes regardless of the orientation of the concentrating element. In some embodiments, a light receiving port (e.g., a waveguide, an optic fiber, etc.) can be positioned at the fixed location to collect the incident converging light. The fixed location can be positioned at a non-focal point of the converging light to reduce hot spots.
Various objects, features, aspects and advantages of the inventive subject matter will become more apparent from the following detailed description of preferred embodiments, along with the accompanying drawing figures in which like numerals represent like components.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 presents a prior art schematic, fragmented, side elevation view of a 3-story portion of a building having prior art building core sunlight illumination system.
FIG. 1A illustrates a cross-sectioned side elevation of the disclosed building core sunlight illumination system. Also shown are an integrated sunshade and sections of curtain wall.
FIG. 2 illustrates an embodiment of a concentration panel.
FIG. 2A presents the concentration panel of FIG. 2 with the mounting frame removed to show the enclosure interior details.
FIG. 2B presents a bottom view of the concentration panel of FIG. 2 depicting the desiccant plug and electrical box location.
FIG. 3 illustrates a populated mounting frame.
FIG. 3A presents the populated mounting frame of FIG. 3 where the stationary optical manifold is shown fragmented.
FIG. 4 illustrates a lower variant of a collector assembly.
FIG. 4A presents a side view of the collector assembly of FIG. 4 with chassis removed from view.
FIG. 4B presents a detail view of a lower portion of the collector assembly of FIG. 4 .
FIG. 4C presents a detail rear view of a lower portion of the collector assembly of FIG. 4 .
FIG. 5 illustrates a front and rear view of a single optical frame.
FIG. 5A presents a more detailed front view of a concentrating element in the single optical frame of FIG. 5 .
FIG. 5B presents a more detailed view illustrating an optical joint behind the concentrating element in the single optical frame of FIG. 5 .
FIG. 6 illustrates a rear view the stationary optical manifold where the stationary optical manifold is shown with several optical fibers.
FIG. 7 illustrates a rear detailed view of the collimator.
FIG. 7A presents a side cut view the light path from the stationary optical manifold through the collimator shown in FIG. 7 .
FIG. 8 illustrates a cut-away view of a building core sunlight illumination system.
DETAILED DESCRIPTION
One should appreciate that the disclosed techniques provide many advantageous technical effects including routing natural light from an exterior portion of a structure to an interior portion of the structure. More specifically, the disclosed subject matter provides the technical affect of routing light along an optical path through an opto-mechanical joint to a fixed point regardless of the incident orientation of the light.
The following discussion provides many example embodiments of the inventive subject matter. Although each embodiment represents a single combination of inventive elements, the inventive subject matter is considered to include all possible combinations of the disclosed elements. Thus if one embodiment comprises elements A, B, and C, and a second embodiment comprises elements B and D, then the inventive subject matter is also considered to include other remaining combinations of A, B, C, or D, even if not explicitly disclosed.
As used herein, and unless the context dictates otherwise, the term “coupled with” and “coupled to” are intended to include both direct coupling (in which two elements that are coupled to each other contact each other) and indirect coupling (in which at least one additional element is located between the two elements).
There is provided a core building sunlighting apparatus, an example of which is shown in FIG. 1A . The building core daylight illumination apparatus system comprises a concentrating panel 60 which collects, concentrates and re-collimates sunlight, and a light guide 65 which provides a reflective channel by which the sunlight is transmitted into the building core. The two components are typically connected by a transition funnel 70 .
The depicted embodiment shows the concentrating panel 60 mounted in typical unified curtain wall 75 and integrated sunshade 80 , although other mounting configurations are possible.
For comparison, prior art concentration panels or canopies 12 , 14 , and 16 is shown in FIG. 1 as part of a multi-storey building 10 . Each one of concentration panels collects and redirects solar light into a corresponding light guide or sunlight distributors 30 , 32 , and 34 . Note the bulkiness of the apparatus and how it alters the line of the building exterior.
FIG. 2 depicts a concentration panel which is a sealed, autonomously powered and controlled assembly that is able to be mounted on the outside of buildings, incorporated within the building envelope or mounted independently such as for a sun shade. Contained within or attached to the enclosure 85 are one or more collector assemblies 90 , a stationary optical manifold (not shown), a collimator (not shown), a photovoltaic panel 95 , the electronic controls printed circuit assembly (PCA) and a mounting frame underlying the assemblies.
The enclosure 85 can include an air-tight box constructed of sheet aluminum or other material on the rear and four side faces, and having a front glass panel 100 providing the front face. The front glass panel 100 can include a glass and vinyl lamination specified for maximum transmission of visible light and filtration of ultraviolet light. The front glass panel 100 is typically bonded to the enclosure 85 with glazing tape and silicone sealant per building construction specifications for structural strength and seal integrity.
A 1″×1″ glazing fin 105 can extend around the side faces of the enclosure 85 at a position such that the concentration panel as shown generally in FIG. 2 can be easily mounted in the glazing pocket of common unitized curtain wall building systems.
Within enclosure 85 as shown in FIG. 2A , there can be a desiccant tube 110 extending from a threaded port on the bottom face of the enclosure 85 into the interior of the enclosure 85 . The pipe can be filled with a granular desiccant, which may be replaced onsite during routine maintenance in order to eliminate condensation within the enclosure.
Also shown is a pass-through printed circuit board (PCB) 115 which provides a sealed connection between electronic components mounted inside the enclosure 85 and the electronic controls mounted outside.
The port of the desiccant tube 110 , seen in FIG. 2B , is sealed with a threaded plug 120 that has an incorporated membrane vent 125 . The enclosure is thus able to breathe through the desiccant such that, within the enclosure 85 , pressure equilibrium with atmosphere is maintained while internal moisture content is controlled.
Flashing details, ridgelines or surface features around the enclosure 85 may be incorporated into concentration panel ensure proper water drainage and allow for multi-unit sealing similar in appearance to current unitized curtain wall with structural silicone glazing.
The rear glass panel 130 seen in FIG. 2B , is where the output sunlight is ported out of the concentration panel. Rear glass panel 130 is specified for maximum light transmission and includes an anti-reflection coating, and can be bonded to the enclosure 85 with glazing tape and silicone sealant for seal integrity.
The electronics controls PCA can be connected to the pass-through PCB 115 on the outside of the enclosure 85 and covered with a removable electronics cover 135 and electronics gasket 140 for onsite access.
FIGS. 3 and 3A depict a populated mounting frame 145 . The mounting frame 145 has attached to it four collector assemblies 90 in a 2×2 array, the stationary optical manifold (not shown) and the collimator 155 at the read of mounting frame 145 . Once populated, the mounting frame 145 is secured within the enclosure 85 . One should appreciate that the number of collector assemblies 90 coupled to mounting frame 145 can be varied according to a desired implementation or deployment. Collector assemblies 90 can be arranged according to other arrays including 1×1, 1×2, 2×1, or other N×M array where N=M or N≠M.
In FIG. 4 , an exemplary single collector assembly 90 is pictured, which includes all optical and mechanical elements required for the tracking of the sun and the collection and concentration of sunlight. The collector assembly 90 consists of a chassis 160 upon which is mounted a linear array of optical frames 165 , an altitude platform 175 , fiber holders 180 , as well as geared drive mechanisms, rotary encoders, and stepper motors for both altitude and azimuth axes.
FIG. 4A depicts the biaxially-mobile mechanical assembly which supports and drives the arrayed optical frames 165 . The upper and lower pivot pins 185 , 190 of each optical frame 165 are mounted in bushings in the chassis such that they can pivot freely and in parallel about their azimuth axes. On each optical frame 165 an altitude frame 170 is attached to each lens holder 195 with pins and bushings such that all the lens holders 195 in the optical frame 165 are linked in a multiple parallelogram four bar mechanism arrangement. The movement of the altitude frame up or down causes all the lens holders 195 to move simultaneously and in parallel about their altitude axes.
In FIG. 4B , linkage arms 200 are attached to the azimuth frames and are in turn connected by pin and bushings to a common linkage bar 205 in a multiple parallelogram four bar mechanism arrangement. The movement of the azimuth frames 210 about their azimuth axes is thus constrained to be simultaneous and parallel.
A detailed drawing of possible drive assemblies for both axes is shown in FIG. 4C . The optical frames 165 are both rotated about their azimuth axes and held in position by a worm gear set, with the worm gear 215 being mounted on the pivot pin of one of the optical frames 165 and the worm being mounted on the azimuth drive shaft 220 . A stepper motor 225 is mounted on the chassis and linked by a flexible coupling to the azimuth drive shaft 220 .
The altitude frames 170 of each optical frame 165 are supported on the flat altitude platform 175 . A roller bearing on each altitude frame 170 is the contact point with the altitude platform 175 . The roller bearing sits freely on the altitude platform 175 and is free to translate in any direction. By moving the altitude platform 175 up or down, all altitude frames 170 are moved simultaneously and in parallel, and thus all lens holders 195 are similarly moved simultaneously and in parallel about their altitude axes. The altitude platform 175 is indexed up and down via a linear slide mechanism 230 that is driven by two lead screws 235 which are in turn driven by a worm gear sets with the worm gear mounted on the two lead screws and the worms mounted on a common altitude drive shaft 240 . A stepper motor 245 is mounted on the chassis and linked by a flexible coupling to the altitude drive shaft 240 .
FIG. 5 provides an overview illustration of a front and rear view of single optical frame 165 . The azimuth axis 295 of frame 165 and altitude axis 290 of each lens holder 195 are shown. Thus, optical frame 165 can rotate about the azimuth axis and each lens holder 195 can tilt up or down by rotating around their corresponding altitude axis 290 .
FIG. 5A depicts an example one of the arrayed opto-mechanical component sets from the optical frame 165 , which includes an azimuth frame 210 , a concentrating element 250 mounted on a lens holder 195 , and an altitude frame 170 and the related mechanical structure and pivot points.
The concentrating element 250 can be a Fresnel or other imaging lens or a non-imaging device such as a waveguide or Winston cone. The preferred configuration of the concentrating element 250 is to be constructed such that the resultant optical path is directed off-axis from the geometrical center line of the lens holder 195 . This arrangement ensures that the mechanical pivot points 280 and 285 can be coincident with the altitude axis 290 and azimuth axis 295 of the mechanical tracking assembly and that the pivot axes are symmetrical with the physical center lines of the lens holder 195 . The symmetry thus defined ensures the maximum packing density of concentration elements 250 in all tracking positions.
FIG. 5B schematically depicts the light path from the concentrating element 250 and through an opto-mechanical joint assembly 500 . As illustrated opto-mechanical joint assembly 500 typically comprises light concentrating element 250 mounted on a rotatable frame assembly configured to rotate about at least two axes. For example, the rotatable frame assembly can include a concentrator holder (see lens holder 195 in FIG. 5A ) able to rotate around altitude axis 290 and azimuth frame 210 able to rotate about azimuth axis 295 .
The opto-mechanical joint assembly 500 can comprise of a series of reflective surfaces represented by two orthogonally rotating reflective surfaces 260 , 265 . Reflective surfaces 260 and 265 can be arranged in a manner that folds or redirects the converging light from concentrating element 250 along an optical path such that the optical path is directed to a fixed location 301 regardless or independent of orientation of the concentrating element 250 about the two tracking axes 290 , 295 . This arrangement makes possible a stationary interface point represented by fixed location 301 with the balance of the system thus eliminating variable loads on the mechanical drives during tracking or physical wear on the optical components.
One should appreciate that the fixed location 301 in the example illustrated comprises a light receiving port in the form of an end of optic fiber 300 . The light receiving port could also include other forms of waveguides other than an optic fiber. Fixed location 301 substantially remains stationary relative to the azimuth axis 295 and altitude axis 290 regardless of how frame 210 rotates or how lens holder 195 tilts. In some embodiments, frame 210 can comprise one or more optic fiber holders (e.g., clips, glue, etc.) that hold optic fiber 300 in place relative to the frame 210 . In such cases, optic fiber 300 can rotate with frame 210 about azimuth axis 295 while the light receiving end of optic fiber 300 remains stationary. In other embodiments, optic fiber 300 can be held stationary by being mounted to other non-moving structures (e.g., enclosures, frames, etc.) in a manner that substantially maintains the receiving end of optic fiber 300 at a fixed location.
When concentrating element 250 is aligned to receive direct natural sunlight, it collects and focuses or concentrates the light as a converging light beam. Prior to reaching the focal or concentration point the converging light is reflected by the first reflective surface 260 and directed along the altitude axis 290 of the lens holder 195 .
Then, still prior to reaching the focal or concentration point, the converging light is reflected by the second reflective surface 265 , which is mounted on the azimuth frame 210 , and directed along the azimuth axis 295 toward the fixed location 301 of the receiving end of optic fiber 300 . Through the two reflections along orthogonal axes 290 and 295 , the focal or concentration point is stationary relative to orthogonal translation in the focal plane. Thus, the converging light is incident on the light receiving port located at fixed location 301 . One should appreciate the fixed location 301 is considered substantially fixed relative to opto-mechanical joint assembly 500 or more specifically fixed relative to axes 290 and 295 . As can be see, fixed location 301 also remains substantially stationary relative to an intersection of axes 290 and 295 .
In FIG. 6 , the stationary optical manifold 150 is shown from the rear. Concentrated sunlight from the output of each opto-mechanical joint is guided to the collimator 155 along optic fibers 300 . In this embodiment, the stationary optical manifold 150 is composed of a set of plastic optical fibers 300 (only some are shown in FIG. 6 , for clarity). Other embodiments of the stationary optical manifold 150 can include a molded acrylic plate or rigid optical fiber assemblies. Care is taken to route the plastic optical fibers to minimize curvature, and so minimize the increase in optical angularity and loss of efficiency caused by such curvature.
The plastic optical fibers 300 can be held in place and orientation at the focal or concentration points of the opto-mechanical joints by fiber holders 180 (see FIG. 4 ) which are mounted on chassis 160 . The fiber holder 180 can be constructed of a metal in order to conduct heat away from the focus or concentration point. Thus, fiber holder 180 can comprises a heat sink. The “face” or end of the plastic optical fiber is typically held just inside or outside of the focal point, such that the amount of concentration is minimized while maintaining full collection. This configuration reduces the surface temperature at the face of the plastic optical fiber and thus mitigates the related thermal degradation effects. The position of the fixed location of the light receiving port of optic fiber 300 is positioned where the area subtended by the light receiving port, A of , is commensurate with the cross sectional area subtended by concentrated light, A cl , at that point just outside the focal point. The ratio of the areas A of /A cl is preferably within 10%, more preferably within 5%, and yet more preferably within 1% of value of one.
FIG. 7 depicts collimator 155 , which receives the output from each opto-mechanical joint in the enclosure 85 via the stationary optical manifold 150 and then combines, re-collimates and redirects the aggregate sunlight through the rear glass panel 130 on the enclosure 85 and then into the entrance of the hybrid light guide 65 .
Light guide performance is predicated on the intensity and degree of collimation of the injected sunlight. The higher the degree of collimation of the sunlight the further the depth of penetration that is possible into a building core or other internal portions of a structure. Sunlight is inherently collimated but the collection, concentration and transport through various mediums and optical components tends to increase the angularity of the exiting light. Sunlight emerging from the exit face of the plastic optical fibers of the stationary optical manifold will therefore benefit from re-collimation for optimal performance of the light guide.
The collimator 155 is mounted on the rear of the mounting frame 145 . The collimator 155 includes two perforated racks 305 , 310 for holding the end faces of the plastic optical fibers 300 of the stationary optical manifold 150 such that the optical axis of each fiber is parallel. The collimator mirror 315 is a highly reflective surface held in a specific parabolic shape intended to optimize the collective collimation of the output in the vertical plane from the aggregated plastic optical fibers 300 mounted in the upper rack 305 .
FIG. 7A schematically depicts the aggregated optical path. The upper rack 305 is oriented such that the optical axis of attached fibers will be perpendicular and centered to the collimator mirror 315 entrance. The lower rack 310 is oriented to allow the plastic optical fibers 300 from the lower corner section of the mounting frame 145 to have their optical axis oriented directly toward the rear glass panel 130 without requiring severe curvature in the fibers. Although the output from these fibers is not re-collimated, it is generally parallel with the output from the collimator mirror 315 . Thus the sunlight output from all opto-mechanical joints within the concentration panel are combined and concentrated in a single, mostly re-collimated, beam which is directed into the hybrid light guide 65 .
FIG. 8 shows an example of an embodiment of a complete optical system for collecting and distributing sunlight as disclosed. A typical light guide 65 includes mechanical construction with prismatic or multi-layer optical film as the primary reflective surface, and extraction film distributed to provide balanced light levels along the length of the light guide. The preferred embodiment of this disclosure includes a hybrid light guide. The hybrid light guide 65 includes integrated fluorescent lamps or other electrically powered light sources along the length of the light guide. The fluorescent lamps supplement the sunlight when it is below a set level of luminance during the day and generally during night operations.
Control of the sunlight and fluorescent mix is achieved by monitoring the environmental light levels with light level sensors mounted on the light guide. The transition from one lighting mode to the other is done such that the occupants of the illuminated area are unaware of the transition. Thus, the hybrid light guide is able to supply a pre-selected level of illuminance at any time of day or in any weather condition.
The transition funnel 70 is the channel from the concentration panel 60 to the hybrid light guide 65 . It is optically optimized for improved collimation by a hollow funnel that expands from a size approximating the rear window of the concentration panel to a size that mates with the entry of the light guide. The transition funnel 70 is lined with highly reflective material. The funnel shape is sized such that light rays that are emerging from the concentration panel 60 at an angle are redirected to a path close to parallel with the center line of hybrid light guide 65 .
In applications where the concentration panel 60 is mounted within the building envelop wall and the rear of the panel is directly accessible to the interior of the building, the transition funnel 70 mounts directly to both the concentration panel 60 and the corresponding hybrid light guide 65 . In applications where the concentration panel 60 is mounted external to the building envelope, the light path must pass through a sealed window panel such that the building envelope is not breached. In this case there will generally be additional light ducting lined with highly reflective material to span the distance from the outside concentration panel 60 to the transition funnel 70 .
The concentration panel 60 as disclosed is autonomous of all wire connections to the building. The concentration panel 60 can therefore be mounted on a building independent of electrical power or data hookup. Power for the control electronics and motion control is self-generated by a photovoltaic panel 95 that is mounted at the lower edge of the front glass panel 100 . Communication with the light level sensors mounted on the hybrid light guides 65 , with the building lighting automation system and for all post-installation calibration or firmware upgrades is accomplished through a wireless communication link.
In the example shown in FIG. 8 the concentration panel 60 has a 10 degree slope but the panel could be mounted vertically or have greater or lesser slopes.
It should be apparent to those skilled in the art that many more modifications besides those already described are possible without departing from the inventive concepts herein. The inventive subject matter, therefore, is not to be restricted except in the scope of the appended claims. Moreover, in interpreting both the specification and the claims, all terms should be interpreted in the broadest possible manner consistent with the context. In particular, the terms “comprises” and “comprising” should be interpreted as referring to elements, components, or steps in a non-exclusive manner, indicating that the referenced elements, components, or steps may be present, or utilized, or combined with other elements, components, or steps that are not expressly referenced. Where the specification claims refers to at least one of something selected from the group consisting of A, B, C . . . and N, the text should be interpreted as requiring only one element from the group, not A plus N, or B plus N, etc. | A light collecting and disseminating apparatus is provided for use in harvesting sunlight from the exterior of a man-made structure, and providing light to the inside of the structure, via an opto-mechanical joint where sunlight would not normally be available. The internal arrangement of the collector allows for improved optical accuracy and performance over prior efforts. The apparatus is also characterized as possessing a low profile so as not to alter the appearance of buildings furnished with the invention. Further, light can be collected from any orientation and redirected through the opto-mechanical joint to a stationary light receiving port independent of the orientation of the collectors. | 5 |
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] Not Applicable.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not Applicable.
INCORPORATION-BY-REFERENCE OF MATERIAL SUBMITTED ON A COMPACT DISK
[0003] Not Applicable.
BACKGROUND OF THE INVENTION
[0004] (1) Field of the Invention
[0005] The present invention is directed to a new class of luminescent gold(III) compounds containing a tridentate ligand and having at least one strong σ-donating group. Such compounds can be used as light-emitting material in phosphorescence based organic light-emitting devices (OLEDs), wherein different colors can be obtained by varying the applied DC voltage or the dopant concentration of said compounds.
[0006] (2) Description of Related Art Including Information Disclosed Under 37 C.F.R. 1.97 and 1.98.
[0007] The market for flat-panel displays has attracted considerable attention in connection with the development of electroluminescent materials. The electroluminescence materials used are generally categorized into conjugated polymers or low-molar-mass small molecules. OLEDs are among the most important candidates for the use of electroluminescent materials in commercial flat-panel displays because OLEDs possess the advantages of robustness, ease of fabrication and color tuning, wide viewing angle, high brightness and contrast ratios, low turn-on voltage and low energy consumption.
[0008] A typical OLED structure is composed of a thin film of organic material sandwiched between a transparent conductor such as indium tin oxide (ITO), and a vapor deposited metal cathode. Upon applying an electrical potential, excitons are formed by the recombination of the holes and electrons, injected from the ITO electrode and metal cathode, respectively. Electroluminescence is generated in the organic material from the radiative relaxation of excitons. Higher performance of the device can be achieved by using multiple organic layers for separation of hole and electron transporting layers.
[0009] Although electroluminescence from organic polymers was initially reported years ago [Kaneto, K.; Yoshino, K.; Koa, K.; Inuishi, Y. Jpn. J. Appl. Phys. 18, 1023 (1974)], it was only after the report on yellow-green electroluminescence from poly(p-phenylenevinylene) (PPV) that light-emitting polymers and OLEDs have received much attention [Burroughs, J. H.; Bradley, D. D. C.; Brown, A. R.; Marks, N.; Friend, R. H.; Burn, P. L.; Holmes, A. B., Nature 347, 539 (1990)]. Later on, similar studies were reported by using PPV derivatives as the light-emitting polymers [Braun, D.; Heeger, A. J., Appl. Phys. Lett. 58, 1982 (1991)]. Since then a number of new electroluminescent polymers have been investigated for improved properties.
[0010] Electroluminescence of organic materials was discovered in anthracene crystals immersed in liquid electrolyte in 1965 [Helfrich, W.; Schneider, W. G. Phys. Rev. Lett. 14, 229 (1965)]. Although lower operating voltages could be achieved by using a thin film of anthracene as well as solid electrodes, very low efficiency of such a single-layer device was encountered. High-performance green electroluminescence from an organic small molecule, aluminum tris(quinolate) (Alq 3 ), was first reported in 1987 [Tang, C. W.; VanSlyke, S. A. Appl. Phys. Lett. 51, 913 (1987)]. A double-layer OLED with high efficiency and low operating voltage was described, in which Alq 3 was utilized both as emitting layer and electron transporting layer. Subsequent modifications of the device with triple-layer structure gave better performance with higher efficiency.
[0011] Some improvements in OLED efficiencies have been achieved by using phosphorescent material to generate light emission from both singlet and triplet excitons. One approach, particularly for small-molecule OLEDs, is to harvest triplet excitons efficiently through incorporation of heavy metal centers, which would increase spin-orbit coupling and hence intersystem crossing into the triplet state. In 1998, Baldo et al. demonstrated a phosphorescence electroluminescence device with high quantum efficiency by using platinum(II) 2,3,7,8,12,13,17,18-octaethyl-21H,23H-porphine (PtOEP) as a dye [Baldo, M. A.; O'Brien, D. F.; You, Y.; Shoustikow, A.; Sibley, S.; Thompson, M. E.; Forrest, S. R. Nature 395, 151 (1998)]. A multilayer device in which the emitting layer of Alq 3 is doped with PtOEP showed a strong emission at 650 nm attributed to the triplet excitons of PtOEP. Cyclometalated iridium(III) is known to show phosphorescence and is another class of materials used for high efficiency OLEDs. Baldo et al. reported the use offac-tri(2-phenylpyridine)iridium(III) [Ir(ppy) 3 ] as phosphorescence emitting material which was doped in 4,4′-N,N′-dicarbazole-biphenyl (CBP) as a host in an OLED to give high quantum efficiency [Baldo, M. A.; Lamansky, S.; Burrows, P. E.; Thompson, M. E.; Forrest, S. R. Appl. Phys. Lett. 75, 4 (1999)]. In addition, fac-tri(2-phenylpyridine)iridium(III) [Ir(ppy) 3 ] was used as phosphorescence sensitizer for high efficiency fluorescent OLED [Baldo, M. A.; Thompson, M. E.; Forrest, S. R. Nature, 403, 750 (2000)]. Using the concept of a phosphorescence emitter with a higher population of excitions, very high efficiency red fluorescence from [2-methyl-6-[2-(2,3,6,7-tetrahydro-1H,5H-benzo[II]quinolizin-9-yl)-ethenyl]-4H-pyran-4-ylidene]propanedinitrile (DCM2) was found in a multilayer OLED composed of Ir(ppy) 3 and DCM2 dopant layers. In a sensitization process, energy is transferred from Ir(ppy) 3 to DCM2 to give such high efficiency fluorescence.
[0012] Apart from the enhancement of the emission efficiency, the ability to bring about a variation in the emission color would be important. Most of the common approaches involve the use of different light-emitting materials or multi-component blended mixtures of light-emitting materials with different emission characteristics for color tuning. Examples that employ a single light-emitting material as dopant to generate more than one emission color have been rare. Recent studies have shown that different emission colors from a single emissive dopant could be generated by using phosphorescent material through a change in the direction of the bias or in the dopant concentration. Welter et al. reported the fabrication of a simple OLED consisting of semiconducting polymer PPV and phosphorescent ruthenium polypyridine dopant [Welter, S.; Krunner, K.; Hofstraat, J. W.; De Cola, D. Nature, 421, 54 (2003)]. At forward bias, red emission from the excited state of the phosphorescent ruthenium polypyridine dopant was observed, while the OLED emitted a green emission at reverse bias in that the lowest excited singlet state of PPV was populated. Adamovich et al. reported the use of a series of phosphorescent platinum(II) [2-(4,6-difluorophenyl)pyridinato-N,C 2′ ] β-diketonates as single emissive dopant in OLED [Adamovich, V.; Brooks, J.; Tamayo, A.; Alexander, A. M.; Djurovich, P. R.; D'Andrade, B. W.; Adachi, C.; Forrest, S. R.; Thompson, M. E. New. J. Chem. 26, 1171 (2002)]. Both blue emission from the monomeric species and orange emission from the aggregates were observed in such OLED and the relative intensity of the orange emission increases as the doping level is increased. As a result, the electroluminescence color can be tuned by changing the dopant concentration, and white illumination sources of an OLED can be obtained in a doping concentration with equal intensities of the monomeric and aggregate bands. In both cases, the change of electroluminescence color in OLED can be accomplished upon a variation of the external stimulus or fabrication conditions while keeping the light-emitting material the same.
[0013] Despite recent interest in electrophosphorescent materials, in particular metal complexs with heavy metal centers, most of the work has been focused on the use of iridium(III), platinum(II) and ruthenium(II), while other metal centers have been relatively less extensively explored. In contrast to the isoelectronic platinum(II) compounds which are known to show rich luminescence properties, very few examples of luminescent gold(III) compounds have been reported, probably due to the presence of low-energy d-d ligand field (LF) states and the electrophilicity of the gold(III) metal center. The introduction of strong σ-donating ligands into gold(III) compounds to enhance the luminescence properties as a result of the enlargement of d-d splitting has been considered. Yam et al. first demonstrated that gold(III) aryl compounds are photo-stable and are capable of displaying interesting photoluminescence properties which occur even at room temperature [Yam, V. W. W.; Choi, S. W. K.; Lai, T. F.; Lee, W. K. J. Chem. Soc., Dalton Trans. 1001(1993)]. Another interesting donor ligand is the alkynyl group. But despite the fact that a number of gold(I) alkynyls are known and have been shown to exhibit interesting luminescence properties, the chemistry of gold(III) alkynyls has been essentially ignored, except for a brief report on the synthesis of an alkynylgold(III) compound of 6-benzyl-2,2′-bipyridine in the literature [Cinellu, M. A.; Minghetti, G.; Pinna, M. V.; Stoccoro, S.; Zucca, A.; Manassero, M. J. Chem. Soc. Dalton Trans. 2823 (1999)], but their luminescence behaviour has remained totally unexplored. The present inventors have described herein the design, synthesis and photoluminescence behaviors of luminescent gold(III) compounds with a tridentate ligand and at least one strong σ-donating group, and the use of such compounds as electrophosphorescent material in OLEDs to give strong electroluminescence with high efficiency.
BRIEF SUMMARY OF THE INVENTION
[0014] The present invention is directed to novel luminescent gold(III) compounds, their preparation, and OLEDs containing them. The compounds have the chemical structure shown in generic formula (I):
wherein R 1 , R 2 , R 3 and R 4 each independently represents a substituent selected from the group consisting of hydrogen, halogen, alkynyl, substituted alkynyl, alkyl, substituted alkyl, aryl, substituted aryl, heteroaryl, substituted heteroaryl, alkoxyl, substituted alkoxyl, amino, substituted amino, cyano, nitro, alkylcarbonyl, alkoxycarbonyl, arylcarbonyl, aryloxycarbonyl, mono- or dialkylaminocarbonyl, alkylcarbonyloxy, arylcarbonyloxy, aryloxy, alkoxycarbonyl, aryloxycarbonyloxy group, and the like; X, Y and Z each independently represent a heteroatom or a carbon;
represents an aromatic or heterocyclic 5- or 6-membered ring; α and β each independently represents a bridge for an aromatic or heterocyclic 5- or 6-membered ring, or a break for a non-cyclic moiety; C—X, C—Y and C-Z each independently represents a single bond or double bond; n is a zero or an integer; and p, q and r are positive integers. The compounds of the present invention each contains one tridentate ligand and at least one strong σ-donating group coordinating to a gold(III) metal center.
[0015] The luminescent gold(III) compounds of the present invention show photoluminescence via triplet excited state upon photo-excitation, or electroluminescence via triplet exciton upon applying a DC voltage. Preferred compounds of the invention are thermally stable and volatile enough to be able to form a thin layer by sublimation or vacuum deposition.
[0016] The present invention is also directed to the use of luminescent compounds of general formula (I) as phosphorescent emitters or dopants fabricated into OLEDs to generate electroluminescence. In one embodiment, the light-emitting material used as a phosphorescent emitter or dopant in an OLED can comprise a gold(III) compound coordinated with one tridentate ligand and at least one strong σ-donating ligand.
[0017] In an OLED according to the present invention, the luminescent compound is included in a light-emitting layer or as a dopant arranged between a pair of electrodes. The typical structure of an OLED using the luminescent compound of the present invention as a light-emitting layer without an electron blocking layer is in the order shown in FIG. 1 : anode/hole transporting layer/luminescent gold(III) compound as a light-emitting layer/electron injection layer/cathode.
[0018] The typical structure of an OLED using the luminescent compound of the present invention as a light-emitting layer with an electron blocking layer is in the order shown in FIG. 2 : anode/hole transporting layer/luminescent gold(III) compound as light-emitting layer/hole blocking layer/electron injection layer/cathode.
[0019] The typical structure of an OLED using the luminescent compound of the present invention as a dopant with an electron blocking layer is in the order shown in FIG. 3 : anode/hole transporting layer/luminescent gold(III) compound doped in host/hole blocking layer/electron transporting layer/cathode.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] FIG. 1 shows the structure of an OLED using the luminescent compound of the present invention as the light-emitting layer without an electron blocking layer.
[0021] FIG. 2 shows the structure of an OLED using the luminescent compound of the present invention as the light-emitting layer with an electron blocking layer.
[0022] FIG. 3 shows the structure of an OLED using the luminescent copolymer of the present invention as a dopant with an electron blocking layer.
[0023] FIG. 4 shows the UV-vis absorption and emission spectra of compound 1 in dichloromethane at 298° K. No instrumental correction was applied for the emission wavelength.
[0024] FIG. 5 shows the UV-vis absorption and emission spectra of compound 4 in dichloromethane at 298° K. No instrumental correction was applied for the emission wavelength.
[0025] FIG. 6 shows the UV-vis absorption and emission spectra of compound 6 in dichloromethane at 298° K. No instrumental correction was applied for the emission wavelength.
[0026] FIG. 7 UV-vis absorption and emission spectra of compound 8 in dichloromethane at 298° K. No instrumental correction was applied for the emission wavelength.
[0027] FIG. 8 shows the solid state (thin film) emission spectrum of compound 1 at 298° K. No instrumental correction was applied for the emission wavelength.
[0028] FIG. 9 shows the solid state (thin film) emission spectrum of compound 8 at 298° K. No instrumental correction was applied for the emission wavelength.
[0029] FIG. 10A shows the multilayer OLED with the structure of ITO/NPB (60 nm)/compound 1 (30 nm)/Alq 3 (10 nm)/LiF (1 nm)/Al (90 nm).
[0030] FIG. 10B shows the electroluminescence spectra of device 1 (see FIG. 1 ) at different applied DC voltages; the emission intensities are normalized in the range of 450-480 nm.
[0031] FIG. 11A shows the multilayer OLED of device 2 (see FIG. 2 ) with the structure of ITO/TPD (70 nm)/compound 1 (10 nm)/Alq 3 (40 nm)/LiF (0.6 nm)/Al (150 nm).
[0032] FIG. 11B shows the electroluminescence spectrum of device 2 (see FIG. 2 ) upon applying 7 V DC voltage.
[0033] FIG. 11C shows the current density and luminance versus voltage characteristics of device 2 (see FIG. 2 ).
[0034] FIG. 11D shows the current and power efficiency versus current density characteristics of device 2 (see FIG. 2 ).
[0035] FIG. 12A shows the multilayer OLED with the structure of device 3 (see FIG. 3 ) ITO/TPD (70 nm)/compound 8 (30 nm)/BCP (30 nm)/Alq 3 (10 nm)/LiF (0.6 nm)/Al (150 nm).
[0036] FIG. 12B shows the electroluminescence spectrum of device 3 (see FIG. 3 ) upon applying 9 V DC voltage.
[0037] FIG. 12C shows the current density and luminance versus voltage characteristics of device 3 (see FIG. 3 ).
[0038] FIG. 12D shows the current and power efficiency versus current density characteristics of device 3 (see FIG. 3 ).
[0039] FIG. 13A shows the multilayer OLED of device 4 with the structure: ITO/TPD (40 nm)/CBP doped with (X %) compound 8 (30 nm)/BCP (20 nm)/Alq 3 (10 nm)[LiF (0.6 nm)/Al (150 nm) [X=1 (device 4 a ), 3 (device 4 b ), 6 (device 4 c ), 12 (device 4 d ), 18 (device 4 e ), 100 (device 4 f )].
[0040] FIG. 13B shows normalized electroluminescence spectra of devices 4 a - f with different concentrations of compound 81% (device 4 a ), 3 (device 4 b ), 6 (device 4 c ), 12 (device 4 d ), 18 (device 4 e ), 100 (device 4 f ) as dopant upon applying 12 V DC voltage.
[0041] FIG. 14A shows device 5 : ITO/TPD (70 nm)/CBP (compound 8, 6 wt %) (30 nm)/TPBi (60 nm)/LiF (1 nm)/Al (150 nm).
[0042] FIG. 14B shows a plot of current density and luminance versus voltage for device 5 .
[0043] FIG. 14C shows a plot of current and power efficiency versus current density for device 5 .
[0044] FIG. 14D plot of quantum efficiency versus current density. Inset: spectra characteristics of device 5 .
DETAILED DESCRIPTION OF THE INVENTION
[0045] The present invention is related to the syntheses, spectral characterization, and luminescence properties of a class of luminescent gold(III) compounds with one tridentate ligand and at least one strong σ-donating group; and the use of such compounds as light-emitting material in OLEDs to provide electroluminescence with high efficiency and brightness. The compounds have the following structural characteristics:
(1) at least one gold metal center at an oxidation state of +3; (2) said one gold metal center having four coordination sites; (3) one tridentate ligand with one to three aromatic or heterocyclic ring(s) coordinating to the gold metal center; (4) one monodentate ligand coordinating to the gold metal center; (5) at least one strong σ-donating ligand coordinating to the gold metal center; and (6) the compounds being charged or neutral.
[0052] Gold(III) compounds have been rarely observed to emit, in contrast to their isoelectronic platinum(II) compounds which are known to display rich luminescence properties. The lack of luminescence behavior in gold(III) compounds may be due to the presence of low-lying d-d ligand field (LF) states and the electrophilicity of the gold(III) metal center. Gold(III) aryl compounds [Yam, V. W. W.; Choi, S. W. K.; Lai, T. F.; Lee, W. K. J. Chem. Soc., Dalton Trans. 1001(1993)] are exceptions in that they show interesting luminescence properties even at room temperature and possess photo-stability upon light irradiation. Without wishing to be bound by theory, it is believed that the coupling of strong σ-donating ligands to gold(III) renders the metal centre more electron-rich, thereby raising the energy of the d-d states, which results in an improvement or enhancement of the luminescence by increasing the chances for population of the emissive state. A class of luminescent gold(III) compounds with one tridentate ligand and at least one strong σ-donating group will be described in detail hereinbelow.
[0053] The luminescent gold(III) compounds of the present invention can be formed into thin films by vacuum deposition, spin-coating or other known fabrication methods. Different multilayer OLEDs have been fabricated using the compounds of the present invention as light-emitting material or as dopant in the emitting layer. In general, the OLEDs consist of one anode and one cathode, between which are the hole transporting layer, light-emitting layer, and electron transporting or injection layer.
[0054] The present invention will be illustrated more specifically by the following non-limiting examples, it being understood that changes and variations can be made therein without deviating from the scope and the spirit of the invention as hereinafter claimed.
EXAMPLE 1
[0000] Synthesis and Characterization
[0055] Compounds 1-8 were synthesized according to the following methodology. The precursor compound, [Au(CˆNˆC)Cl], was prepared according to the modification of a procedure reported in the literature [Wong, K. H.; Cheung, K. K.; Chan, M. C. W.; Che, C. M. Organometallics, 17, 5305(1998)]. The desired compounds were synthesized by the reaction of [Au(CˆNˆC)Cl] with various alkynes in the presence of a base or copper catalyst in an organic solvent. For example, to a mixture of [Au(CˆNˆC)Cl], terminal alkyne and Et 3 N in degassed dichloromethane solution was added CuI. The reaction mixture was stirred for 6 hours under a nitrogen atmosphere at room temperature. The crude product was purified by column chromatography on silica gel using dichloromethane as eluent. Pale yellow crystals were obtained from slow diffusion of diethyl ether into the dichloromethane solution of the compounds.
R = C 6 H 5 (1) C 6 H 4 —Cl-p (2) C 6 H 4 —NO 2 -p (3) C 6 H 4 —OCH 3 -p (4) C 6 H 4 —C 6 H 13 -p (5) C 6 H 4 —NH 2 -p (6) C 6 H 13 (7) C 6 H 4 —N(C 6 H 5 ) 2 -p (8)
[0056] The characteristic spectral properties of compounds 1-8 are as follows:
[Au(CˆNˆC)C≡C—C 6 H 5 ] (Compound 1)
[0057] Yield: 88%. 1 H NMR (300 MHz, CH 2 Cl 2 , 298° K., relative to Me 4 Si): δ 8.04 (dd, 7.4 and 1.0 Hz, 2H, CˆNˆC), 7.92 (t, 8.0 Hz, 1H, CˆNˆC), 7.62 (m, 4H, CˆNˆC and C 6 H 5 ), 7.54 (d, 8.0 Hz, 2H, CˆNˆC), 7.26-7.44 (m, 7H, CˆNˆC and C 6 H 5 ); positive EI-MS: m/z 527 [M] + ; IR (KBr): 2147 cm −1 v(C≡C); elemental analyses calc'd for C 25 H 16 NAu (found): C 56.93 (56.57), H 3.04 (3.05), N 2.66 (2.66).
[Au(CˆNˆC)C≡C—C 6 H 4 —Cl-p] (Compound 2)
[0058] Yield: 85%. 1 H NMR (300 MHz, CH 2 Cl 2 , 298° K, relative to Me 4 Si): δ 8.00 (dd, 7.2 and 1.0 Hz, 2H, CˆNˆC), 7.90 (t, 8.0 Hz, 1H, CˆNˆC), 7.50-7.60 (m, 6H, CˆNˆC and C 6 H 4 ), 7.25-7.42 (m, 6H, CˆNˆC and C 6 H 4 ); positive EI-MS: m/z 562 [M] + ; IR (KBr): 2157 cm −1 v(C≡C); elemental analyses calc'd for C 25 H 15 NClAu.½H 2 O (found): C 52.59 (52.85), H 2.80 (2.66), N 2.45 (2.40).
[Au(CˆNˆC)C≡C—C 6 H 4 —NO 2 -p] (Compound 3)
[0059] Yield: 80%. 1 H NMR (400 MHz, CH 2 Cl 2 , 298° K., relative to Me 4 Si): δ 8.22 (d, 9.0 Hz, 2H, C 6 H 4 ), 8.00 (dd, 7.6 and 1.2 Hz, 2H, CˆNˆC), 7.94 (t, 8.0 Hz, 1H, CˆNˆC), 7.73 (d, 9.0 Hz, 2H, C 6 H 4 ), 7.64 (dd, 7.6 and 1.2 Hz, 2H, CˆNˆC), 7.55 (d, 8.0 Hz, 2H, CˆNˆC), 7.41 (dt, 7.3 and 1.3 Hz, 2H, CˆNˆC), 7.32 (dt, 7.3 and 1.3 Hz, 2H, CˆNˆC); positive EI-MS: m/z 572 [M] + ; IR (KBr): 2146 cm −1 v(C≡C); elemental analyses calc'd for C 25 H 15 N 2 O 2 Au (found): C 51.64 (51.62), H 2.75 (2.69), N 4.82 (4.75).
[Au(CˆNˆC)C≡C—C 6 H 4 —OCH 3 -p] (Compound 4)
[0060] Yield: 86%. 1 H NMR (400 MHz, CH 2 Cl 2 , 298° K., relative to Me 4 Si): δ 8.02 (dd, 7.6 and 1.0 Hz, 2H, CˆNˆC), 7.90 (t, 8.0 Hz, 1H, CˆNˆC), 7.60 (dd, 7.6 and 1.0 Hz, 2H, CˆNˆC), 7.50-7.56 (m, 4H, CˆNˆC and C 6 H 4 ), 7.40 (dt, 7.3 and 1.3 Hz, 2H, CˆNˆC), 7.27 (dt, 7.3 and 1.3 Hz, 2H, CˆNˆC), 6.91 (d, 8.9 Hz, 2H, C 6 H 4 ), 3.88 (s, 3H, OCH 3 ); positive EI-MS: m/z 557 [M] + ; IR (KBr): 2157 cm −1 v(C≡C); elemental analyses calc'd for C 26 H 18 NOAu.½H 2 O (found): C 55.12 (55.15), H 3.36 (3.28), N 2.47 (2.48).
[Au(CˆNˆC)C≡C—C 6 H 4 —C 6 H 13 -p] (Compound 5)
[0061] Yield: 75%. 1 H NMR (300 MHz, CH 2 Cl 2 , 298° K., relative to Me 4 Si): δ 8.00 (dd, 7.4 and 1.0 Hz, 2H, CˆNˆC), 7.87 (t, 8.0 Hz, 1H, CˆNˆC), 7.57 (dd, 7.4 and 1.0 Hz, 2H, CˆNˆC), 7.47-7.51 (m, 4H, CˆNˆC and C 6 H 4 ), 7.37 (dt, 7.3 and 1.3 Hz, 2H, CˆNˆC), 7.24 (dt, 7.3 and 1.3 Hz, 2H, CˆNˆC), 7.18 (d, 8.3 Hz, 2H, C 6 H 4 ), 2.64 (t, 7.7 Hz, 2H, CH 2 —CH 2 —(CH 2 ) 3 —CH 3 ), 1.64 (m, 2H, CH 2 —CH 2 —(CH 2 ) 3 —CH 3 ), 1.34 (m, 6H, CH 2 —CH 2 —(CH 2 ) 3 —CH 3 ), 0.90 (t, 7.0 Hz, 3H, CH 2 —CH 2 —(CH 2 ) 3 —CH 3 ); positive EI-MS: m/z 611 [M] + ; IR (KBr): 2149 cm −1 v(C≡C); elemental analyses calc'd for C 31 H 28 NAu.½H 2 O (found): C 60.00 (59.91), H 4.68 (4.60), N 2.26 (2.25).
Au(CˆNˆC)C≡C—C 6 H 4 —NH 2 -p] (Compound 6)
[0062] Yield: 80%. 1 H NMR (300 MHz, CH 2 Cl 2 , 298° K., relative to Me 4 Si): δ 8.07 (dd, 7.4 and 1.0 Hz, 2H, CˆNˆC), 7.92 (t, 8.0 Hz, 1H, CˆNˆC), 7.65 (dd, 7.4 and 1.0 Hz, 2H, CˆNˆC), 7.56 (d, 8.0 Hz, 2H, CˆNˆC), 7.39-7.45 (m, 4H, CˆNˆC and C 6 H 4 ), 7.30 (dt, 7.5 and 1.3 Hz, 2H, CˆNˆC), 6.67 (d, 8.6 Hz, 2H, C 6 H 4 ), 3.84 (s, 2H, NH 2 ); positive EI-MS: m/z 542 [M] + ; IR (KBr): 2143 cm −1 v(C≡C); elemental analyses calc'd for C 25 H 17 N 2 Au.½H 2 O (found): C 54.45 (54.59), H 3.27 (3.13), N 5.08 (5.04).
[Au(CˆNˆC)C≡C—C 6 H 13 ] (Compound 7)
[0063] Yield: 85%. 1 H NMR (300 MHz, CH 2 Cl 2 , 298° K, relative to Me 4 Si): δ 8.00 (dd, 7.2 and 1.0 Hz, 2H, CˆNˆC), 7.90 (t, 8.0 Hz, 1H, CˆNˆC), 7.62 (dd, 7.2 and 1.0 Hz, 2H, CˆNˆC), 7.53 (d, 8.0 Hz, 4H, CˆNˆC), 7.40 (dt, 7.3 and 1.3 Hz, 2H, CˆNˆC), 7.28 (dt, 7.3 and 1.3 Hz, 2H, CˆNˆC), 2.49 (t, 6.9 Hz, 2H, CH 2 —(CH 2 ) 2 —(CH 2 ) 2 —CH 3 ), 1.63-1.71 (m, 4H, CH 2 —(CH 2 ) 2 —(CH 2 ) 2 —CH 3 ), 1.40 (m, 4H, CH 2 —(CH 2 ) 2 —(CH 2 ) 2 —CH 3 ), 0.95 (t, 7.0 Hz, 3H, CH 2 —(CH 2 ) 2 —(CH 2 ) 2 —CH 3 ); positive EI-MS: m/z 536 [M] + ; IR (KBr): 2155 cm −1 v(C≡C); elemental analyses calc'd for C 25 H 24 NAu (found): C 56.08 (55.96), H 4.52 (4.60), N 2.62 (2.53).
[Au(CˆNˆC)C≡C—C 6 H 4 —N(C 6 H 5 ) 2 -p] (Compound 8)
[0064] Yield: 72%. Yield: 80%. 1 H NMR (300 MHz, CH 2 Cl 2 , 298° K, relative to Me 4 Si): δ 8.05 (dd, 7.2 and 1.2 Hz, 2H, CˆNˆC), 7.92 (t, 8.0 Hz, 1H, CˆNˆC), 7.64 (dd, 7.2 and 1.2 Hz, 2H, CˆNˆC), 7.56 (d, 8.0 Hz, 2H, CˆNˆC), 7.48 (d, 8.8 Hz, 2H, CˆNˆC), 7.42 (t, 7.2 Hz, 2H, CˆNˆC H's), 7.32-7.26 (m, 6H, CˆNˆC, C 6 H 4 and N—C 6 H 5 ), 7.14-7.02 (m, 8H, CˆNˆC, C 6 H 4 and N—C 6 H 5 ); positive EI-MS: m/z 694 [M] + ; IR (KBr): 2143 cm −1 v(C≡C); elemental analyses calc'd for C 37 H 25 N 2 Au.½H 2 O (found): C 60.85 (61.10), H 3.67 (3.53), N 3.78 (3.80).
[0000] UV-Vis Absorption Properties
[0065] All the luminescent gold(III) compounds exhibit an intense absorption band at 312-327 nm and a moderately intense vibronic-structured absorption band at 362-426 nm in dichloromethane at 298° K. The photophysical data of 1-8 are summarized in Table 1. In general, the electronic absorption energies are insensitive to the nature of the alkynyl ligands. The low-energy vibronic-structured absorption band show vibrational progressional spacings of 1310-1380 cm −1 , corresponding to the skeletal vibrational frequency of the CˆNˆC ligand. Such low-energy absorptions are assigned as intraligand (IL) π−π* transition. An additional shoulder appeared in each of the electronic absorption spectra of compounds 6 and 8 at ca. 415 and 426 nm, respectively (see FIGS. 6 and 7 ). Since the alkynyl ligand with electron-rich amino substituent has better electron-donating property, the presence of a low-lying alkynyl-to-diarylpyridine ligand-to-ligand charge transfer (LLCT) transition is possible. Thus the low-energy absorptions in compounds 6 and 8 are assigned as an admixture of intraligand (IL) π−π*(CˆNˆC)/LLCT π (C≡C—C 6 H 4 —NR 2 -p)→π*(CˆNˆC) transition.
[0000] Photoluminescence Properties
[0066] Unlike most other Au(III) compounds which are non-emissive or only show luminescence at low temperature compounds, 1-8 display intense luminescence at 468-625 nm in the solution state at room temperature (Table 1). In general, the emission energies of the compounds were found to be insensitive to the nature of the alkynyl ligands ( FIGS. 1 and 2 ). A vibronic-structured emission band with band maximum at 473 nm is observed for 1-5 and 7 in dichloromethane at room temperature. The vibrational progressional spacings of ca. 1300 cm −1 are in line with the C≡C and C═N stretching frequency of the tridentate ligand, indicative of the involvement of tridentate ligand in the excited state origin. Similar to the low-energy absorption band in the electronic absorption studies, the luminescence is assigned as originated from metal-perturbed intra-ligand 3 [π−π*] state of the tridentate CˆNˆC ligand. Compounds 6 and 8 exhibit a structureless emission band at lower energy in dichloromethane at room temperature ( FIGS. 3 and 4 ). The emission spectra of compounds 1-8 in the solid state show a low-energy structureless band at around 570 nm ( FIGS. 4 and 5 ). The red shift of the solid-state emission relative to that in the solution state is attributed to the excimeric intraligand emission arising from the π stacking of the CˆNˆC ligand, probably due to the ordered packing of the molecules in the solid state.
TABLE 1 Photophysical data for Compounds 1 through 8. Absorption λmax [nm] Emission Compound Medium (T[K]) (εmax[dm 3 mol −1 cm −1 ]) λmax [nm] 1 CH 2 Cl 2 (298) 312 (19890), 322 476, 506, (19980), 364 (5050), 541, 582 381 (5870), 402 (4870) Solid (298) 588 Thin film 568 (298) a 2 CH 2 Cl 2 (298) 312 (19400), 322 476, 506, (19640), 365(4640), 539, 584 382(5170), 402(4305) Solid (298) 558 3 CH 2 Cl 2 (298) 312 sh (27160), 327 477, 508, (36005), 364 sh 546, 593 (17995), 382 sh (10170), 403 (5630) Solid (298) 563 4 CH 2 Cl 2 (298) 312 (13820), 322 474, 505, (13455), 362 (6400), 539, 584 380 (6245), 400 (4190) Solid (298) 555 5 CH 2 Cl 2 (298) 312 (17855), 322 475, 505, (18100), 363 (5785), 538, 583 381 (5945), 401 (4455) Solid (298) 556 6 CH 2 Cl 2 (298) 310 (19195), 322 sh 611 (15680), 365 (8855) 381 (10100), 399 (8300), 415 sh (3410) Solid (298) 585 7 CH 2 Cl 2 (298) 311 (14775), 320 473, 505, (13925), 364 (3810), 537, 583 380 (4900), 400 (4280) Solid (298) 555 8 CH 2 Cl 2 (298) 312 (37090), 322 625 (38325), 364 (8525), 384 (10040), 400 (10035), 426 sh (4145) Thin film 564 (298) a a prepared by vacuum deposition
EXAMPLE 2
[0067] FIG. 10A shows an illustrative OLED structure of device 1 : ITO/4,4′-bis[N-(1-naphtyl)-N-phenyl-amino]biphenyl (NPB) (60 nm)/compound 1 (30 nm)/aluminum tris(8-hydroxyquinoline) (Alq 3 ) (10 nm)/LiF (1 nm)/Al (90 nm). NPB and Alq 3 act as the hole transporting material and the electron transporting or injection material, respectively. Electroluminescence spectra of device 1 at different DC voltages applied are shown in FIG. 10B . In general, both the emission band of NPB in the range of 450-520 nm and the emission band of compound 1 at about 585 nm are observed upon application of DC voltage. At a lower DC voltage, the emission arising from compound 1 is more intense relative to the emission band of NPB. Upon increasing the DC voltage, the relative emission intensity ratio of compound 1: NPB decreases gradually. Therefore, the emission color of device 1 can be tuned from orange to green by applying different DC voltages.
EXAMPLE 3
[0068] FIG. 11A shows an illustrative OLED structure of device 2 : ITO/N,N′-diphenyl-N,N′-bis(3-methylphenyl)-[1,19-biphenyl]-4,4′-diamine (TPD) (70 nm)/compound 1 (10 nm)/Alq 3 (40 nm)/LiF (0.6 nm)/Al (150 nm). TPD acts as the hole transporting material. The electroluminescence spectrum of device 2 is depicted in FIG. 11B . The EL spectrum shows only one band at around 585 nm. The EL spectrum compares well with the photoluminescence (PL) spectrum of compound 1 ( FIG. 7 ), indicating that both EL and PL arise from the same excited state or the same type of exciton, which is attributed to the excimeric intraligand emission resulting from the π stacking of the CˆNˆC ligand. FIGS. 11C and 11D show the characteristics of device 2 with the relationship between current density, luminance and voltage; and between current, power efficiency and current density. The turn-on voltage is about 5 V.
EXAMPLE 4
[0069] FIG. 12A shows an illustrative OLED structure of device 3 : ITO/TPD (70 nm)/compound 8 (30 nm)/2,9-dimethyl-4,7-diphenyl-1,10-phenathroline (BCP) (30 nm)/Alq 3 (10 nm)/LiF (0.6 nm)/Al (150 nm). BCP acts as the hole blocking material. The electroluminescence spectrum of device 3 is depicted in FIG. 12B . The EL spectrum shows only one band at around 580 nm. The EL spectrum compares well with the photoluminescence (PL) spectrum of compound 8 (shown in FIG. 5 ), indicating that both EL and PL arise from the same excited state or the same type of exciton, which is attributed to the excimeric intraligand emission resulting from the 7 stacking of the CˆNˆC ligand. FIGS. 12C and 12D show the characteristics of device 3 with the relationship between current density, luminance and voltage; and between current, power efficiency and current density. The turn-on voltage is about 6.5 V. The relatively higher turn on voltage is due to the increase in emitting layer thickness (30 nm) and the introduction of an additional hole blocking layer.
EXAMPLE 5
[0070] FIG. 13A shows the general OLED structure: ITO/TPD (70 nm)/4,4′-N,N′-dicarbazole-biphenyl (CBP) doped with (X %) compound 8 (30 nm)/BCP (30 nm)/Alq 3 (10 nm)/LiF (0.6 nm)/Al (150 nm) [X=1 (device 4 a ), 3 (device 4 b ), 6 (device 4 c ), 12 (device 4 d ), 18 (device 4 e ), 100 (device 4 f )]. CBP acts as the host material. FIG. 13B displays the normalized EL spectra of devices 4 a - f with different concentration of compound 8 as dopant upon applying 12 V DC voltage. It is clear that the EL band shifts to red from 500 nm to 580 mm upon increasing the dopant concentration. Since the emitting layer in device 4 is fabricated by the simultaneous vacuum deposition of compound 8 and the host, a higher dopant concentration of compound 8 may give rise to a higher order and better packing of the molecules, leading to stronger it stacking of the CˆNˆC ligand, and hence a lower energy excimeric intraligand emission. Therefore, a dependence of the EL color on the dopant concentration of the luminescent gold(III) compound, leading to concentration-dependent color tuning, can be accomplished in the present invention.
EXAMPLE 6
[0071] Device 5 with the following OLED structure: ITO/TPD (70 nm)/CBP (compound 8, 6 wt %) (30 nm)/1,3,5-tris(2′-(1′-phenyl-1′-H-benzimidazole)benzene (TPBi) (60 nm)/LiF (1 nm)/Al (150 nm) is fabricated ( FIG. 13 ). Higher efficiency is obtained in device 5 by using TPBi as electron transporting material which has higher mobility than Alq 3 . The characteristics of device 5 are illustrated in FIG. 13B which shows (a) plot of current density and luminance versus voltage; (b) plot of current and power efficiency versus current density; and (c) plot of quantum efficiency versus current density. Inset: spectra characteristics of device 5 . | A class of luminescent gold(III) compounds with a tridentate ligand and at least one strong σ-donating group having the chemical structure represented by the general formula (I):
wherein R 1 -R 4 each independently represent the group containing hydrogen, halogen, alkynyl, substituted alkynyl, alkyl, substituted alkyl, aryl, substituted aryl, heteroaryl, substituted heteroaryl, alkoxyl, substituted alkoxyl, amino, substituted amino, cyano, nitro, alkylcarbonyl, alkoxycarbonyl, arylcarbonyl, aryloxycarbonyl, mono- or dialkylaminocarbonyl, alkylcarbonyloxy, arylcarbonyloxy, aryloxy, alkoxycarbonyl, aryloxycarbonyloxy group, and the like; X, Y and Z each independently represent a heteroatom or a carbon;
represents an aromatic or heterocyclic 5- or 6-membered ring; α and β each independently represent a bridge for an aromatic or heterocyclic 5- or 6-membered ring or represent a break for non-cyclic moiety; C—X, C—Y and C-Z each independently represent a single bond or double bond; n represents a zero or an integer; p, q and r represent positive integers. | 2 |
This application claims priority to provisional application No. 60/468,614 filed May 6, 2003 now abandoned, which contents are incorporated by reference as if fully rewritten herein.
This invention was made with Government support under Contract DE-AC0676RLO-1830 awarded by the U.S. Department of Energy. The Government has certain rights in the invention.
BACKGROUND OF THE INVENTION
(1) Field of the Invention
The present invention relates generally to reaction pathways and processes for chemical conversion of amino acids and amides to selective conversion products. More particularly, the present invention relates to selective chemical reaction of L-glutamic acid [CAS no. 56-86-0] and L-pyroglutamic acid [CAS no. 98-79-3] and other related compounds yielding intermediate and end-use products at greater-than-expected yields. Such compounds find applications in such commercial products as solvents, plastics, epoxies, coatings, and urethanes.
(2) Background
Metal catalyzed hydrogenation reactions in the presence of acid at low pH have been shown in several early seminal publications. FIGS. 1 a – 1 c illustrate conversion products stemming from the pioneering work of Adkins et al. ( FIG. 1 a ), Carnahan et al. ( FIG. 1 b ), and Broadbent et al. ( FIG. 1 c ). Adkins et al. ( J. Am. Chem. Soc., 1934, 56, p. 689) used various transition metal oxides including those of nickel, copper, and chromium to reduce carboxylic acid esters to alcohols, including, as illustrated in FIG. 1 a , conversion of butyl lactate to propylene glycol. Adkins et al. ( J. Am. Chem. Soc., 1938, 60, p. 402) later reported reduction of amides via hydrogenation reactions in which Cu—Cr oxide catalysts were used and reduction of a lactam carbonyl using a ruthenium catalyst. Results showed reduction of amides in water typically yields amines whereas reduction of lactams yields alcohols. Carnahan et al. ( J. Am. Chem. Soc., 1955, 77, p. 3766) demonstrated conversion of di-carboxylic acids to diols using a ruthenium metal catalyst, as illustrated in FIG. 1 b . Broadbent et al. ( J. Am. Chem. Soc., 1959, 24, p. 1847) later used a rhenium “black” catalyst to deaminate and hydrogenate amino acids yielding aliphatic alcohols, as illustrated in FIG. 1 c.
The stereo-specific hydrogenation of amino acids has also been reported in the prior art. U.S. Pat. Nos. (5,536,879), (5,731,479), and (6,310,254) assigned to Bayer disclose hydrogenation reactions involving amino acids requiring conditions of low solution pH, extremely high ruthenium oxide/rhenium oxide (RuO 2 /Re 2 O 7 ) catalyst loading, large hydrogen partial pressures (3000 psi), prolonged reaction times (e.g., 8 hours), and reaction temperatures near 70° C. Product yields for the conversion products glutamic acid and pyroglutamic acid were reported to be 58% and 65%, respectively, with an enantiomeric excess approaching 98.3%.
In more recent work by Miller et al. [ Organic Letters, 2003, 5(4), p. 527], the conversion of alanine to desired products stresses the importance of performing hydrogenations at low pH such that the amino acid is in protonated form rather than carboxylate form. Miller et al. further disclose conditions of a 5% ruthenium metal catalyst and partial hydrogen pressures of 6.9 Mpa (1000 psi). Under neutral pH conditions the zwitterion is not reported to reduce to a functional moiety of interest and favorable reduction of amino acids is minimal.
In general, the prior art teaches that reactions to reduce amino acids require a low solution pH in conjunction with high catalyst loading, prolonged reaction times, and large hydrogen partial pressures. The present invention demonstrates novel pathways and conditions not taught or suggested in the literature for converting amino acids, amides, and substituted amides to highly desirable intermediate and end-use products at high selectivity and high yield.
SUMMARY OF THE INVENTION
The present invention generally provides processes for converting amines and amides to highly desirable intermediate and end-use products at both high selectivity and high yield. In particular, the present invention relates to selective chemical reaction of L-glutamic acid and L-pyroglutamic acid (5-oxopyrrolidine-2-carboxylic acid) forming numerous conversion products.
In one embodiment, the conversion product is selected from amines, cyclic amines, alcohols, or combinations thereof. In another embodiment, the conversion product is prolinol. In yet another embodiment, the conversion product contains a ring having a carbon number in the range from about 4 to about 7.
The processes of the present invention generally comprise the steps: a) providing a starting material in a solvent; b) optionally reacting said material thereby yielding at least one amide; and, c) reducing at least one amide in the presence of a reduction catalyst thereby yielding at least one amine at high yield. Starting materials are preferably selected from amides, lactams including but not limited to pyrrolidinones, 2-pyrrolidinone and N-methylpyrrolidinone being representative but not exclusive, and amino acids, glutamic acid being representative but not exclusive.
In one embodiment, the starting material comprises a member selected from: amino acids, amides, lactams, pyrrolidinones, or combinations thereof. In another embodiment the starting material comprises a member selected from glutamic acid, pyrrolidinones, 2-pyrrolidinone, N-methyl pyrrolidinone, pyroglutamic acid, pyroglutaminol, or combinations thereof. In yet another embodiment, the starting material comprises amino acids selected from lysine, aspartic acid, asparagine, glutamine, glutamic acid, arginine, pyroglutamic acid, ornithine, or combinations thereof. In still yet another embodiment, the starting material comprises a carbon number in the range from about 1 to about 20. The term amino acid as used herein refers to moieties having an amino group (i.e., NH 2 ) and an acid group (i.e., COOH). The term “reacting” as used herein refers to reactions including, but not limited to, cyclization, condensation, hydrogenation, reduction, decarboxylation, deamination, and combinations thereof. Conditions are specified that result in high yields under selected conditions of elevated temperature, controlled solution pH, and precious-metal catalyst combinations.
It is an object of the present invention to show conversion of amino acids at enhanced conversion rates in the presence of catalysts, e.g., precious metal catalysts on supports.
It is further an object of the present invention to show conversion of carboxylic acid functional groups of glutamic acid and other amino acids to yield desirable intermediate and end-use products.
It is still further an object of the present invention to show it may be unexpectedly undesirable to convert certain amino acid moieties under conditions of low pH.
BRIEF DESCRIPTION OF THE DRAWINGS
A more complete appreciation of the invention will be readily obtained by reference to the following description of the accompanying drawings in which like numerals in different figures represent the same structures or elements.
FIGS. 1 a – 1 c present teaching in the prior art to metal catalyzed hydrogenation reactions.
FIG. 2 illustrates a reaction vessel for practicing the process of the present invention.
FIG. 3 a illustrates a general reaction scheme for conversion of a pyrrolidinone to a pyrrolidine, according to an embodiment of the present invention.
FIG. 3 b illustrates a typical reaction scheme for conversion of glutamic acid, a representative amino acid, to prolinol (pyrrolidin-2-yl-methanol or PRO), according to an embodiment of the present invention.
FIG. 4 a illustrates a first reaction scheme for conversion of an esterified amino acid via an acid-promoted hydrogenation reaction to yield pyroglutaminol (5-hydroxymethyl-2-pyrrolidinone or 5-HMP), according to a further embodiment of the present invention.
FIG. 4 b illustrates an alternate reaction scheme for conversion of an amino acid starting material to yield N-alkylated substituted pyrrolidinones, including N-alkylated pyroglutaminol, according to a further embodiment of the present invention.
FIG. 5 a illustrates a first typical reaction scheme for protection and selective conversion of an amino acid starting material comprising various functional groups to 4-amino-5-ol-pentanoic acid according to an additional embodiment of the present invention.
FIG. 5 b illustrates a second typical reaction scheme involving glutamic acid for increasing the yield of a desired end product via esterification, cyclization, and subsequent ring opening according to an additional embodiment of the present invention.
FIG. 6 illustrates a typical selective reduction of glutamic acid to yield proline according to a still further embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
While the present invention is described herein with reference to the preferred embodiments thereof, it should be understood that the invention is not limited thereto, and various alternatives in form and detail may be made therein without departing from the spirit and scope of the invention. In particular, those skilled in the art will appreciate that the methods set forth herein for producing specific moieties or other similar chemical products or intermediates can be derived with high specificity, high selectivity, and/or high yield.
The term “yield” as used herein refers to a quantity formed of product of interest. Yield is calculated as conversion multiplied by selectivity, i.e., [Y]ield=[C]onversion×[S]electivity, where “conversion” is a measure of the quantity of starting material consumed in a specified reaction pathway. The term “high yield” as used herein refers to a useful molar percent yield in the range from about 60 percent to about 100 percent, and more preferably above about 75 percent. The term “selectivity” refers to and is calculated as a quantity of product of interest as a ratio of all products formed. The term “high selectivity” as used herein refers to a value above about 70 percent, and more preferably above about 85 percent.
FIG. 2 illustrates a typical reaction vessel (or reactor) 200 for practicing the process of the present invention. The reactor 200 (for example, a model 4565 Mini Reactor from Parr Instrument Co., Moline, Ill.) comprises a 100 mL high-pressure cylinder 205 and a cap assembly 210 made preferably of stainless steel or Hasteloy® or another high-refractory metal for operating temperatures up to about 350° C. The cap assembly 210 further comprises a pressure gauge 215 , a gas inlet valve 220 , a dip tube 225 for sampling, a magnetic stirring mechanism 230 for mixing vessel contents, a venting assembly 235 , and a water cooling loop 240 for controlling temperature of the reactor vessel and contents.
The reactor cylinder and contents are sealed using two C-shaped capping rings (not shown) that mount over protruding edges machined into the cylinder 205 and cap assembly 210 , respectively, and are secured in place by three capping screws located in each capping ring. The vessel cylinder inserts into a heater core 245 that heats the vessel contents. The assembled reactor vessel is secured into a supporting rack (not shown) providing stability at stirring speeds up to 1700 rpm. The vessel is further interfaced to a programmable pressure and temperature controller 250 (for example, a 4843 controller from Parr Instrument Co., Moline, Ill.).
Catalysts, solvents, and reagents may be added to the reactor vessel 205 prior to assembly. For example, the catalyst is preferably introduced to the reactor in a pre-reduced powder form prior to adding starting materials, but may be reduced in situ or in the vessel prior to adding other reagents. A filter 226 at the base of the dip tube 225 prevents powdered catalyst from entering the tube. The reactor is pressurized with nitrogen through the gas inlet port 220 to a pressure of from about 100 to about 500 psi and vented three times using the vent valve 235 . The reactor is then pressurized with hydrogen to the desired starting pressure prior to heating. Samples are withdrawn by closing the gas inlet port and opening the dip tube and collecting fluid samples in a sample vial. Samples are allowed to cool to room temperature prior to analysis.
The reactor 200 may be alternately charged by loading solutions through the vent line 235 . Solutions can be pumped in, or drawn in via gravity or vacuum. Because glutamic acid (GLU) has low solubility in water at 25° C. (8.64 g/L) [Merck Index, 10th ed., 1983, p. 641], or about 0.86 wt %, the solutions must be heated depending on the desired concentration for the starting materials. For example, at 50° C., GLU solubility increases to about 2.1 wt %; at 100° C. solubility increases still further to about 14 wt %. Alternatively, the solid may be added directly to the reactor vessel prior to heating or as the salt of the acid.
The conversion of starting materials under acid-promoted hydrogenation conditions will now be described according to a process of the present invention. FIG. 3 a illustrates a first generalized reaction scheme for conversion of pyrollidinones 310 to form pyrollidines 320 , a desirable class of end-product compounds. As shown in the figure, the lactam carbonyl of the pyrollidinone (i.e., carbonyl of the cyclic amide) 312 is selectively reduced. Reduction is effected in the presence of a reduction catalyst, a hydrogen partial pressure of up to about 3000 psi, and a preferred temperature of up to about 200° C. with a temperature of approximately 150° C. being more preferred, all in the presence of an acidic medium whereby the acid-promoted hydrogenation reaction occurs. FIG. 3 b illustrates a second complete reaction pathway for conversion of a GLU 330 starting material, a representative amino acid, under acid-promoted hydrogenation conditions yielding a desirable pyrollidine end product, e.g., prolinol 336 (PRO). The starting material is first cyclized to yield pyroglutamic acid (PGA), a pyrrolidinone 332 (or cyclic amide). The acidic functional groups of the pyrrolidinone are converted under continued acid-promoted reduction conditions to form the alcohol, i.e., pyroglutaminol 334 (PGOL) or 5-HMP. A reaction step in the conversion of the pyrrolidinone 334 to a final pyrrolidine 336 product comprises reducing the lactam carbonyl 333 functional group ultimately yielding PRO 336 . However, the reaction may be run under conditions that favor formation of either PGOL 334 or PRO 336 . For example, in the presence of acid (e.g., H 3 PO 4 or other mineral acid), conversion of the starting material is nearly 100 percent, with a molar ratio of PGOL to PRO formed being as high as 1 to 98. Under conditions in which no acid is added, PGOL is favored with a molar ratio of about 6 to 1 (PGOL: PRO).
Reaction (e.g., cyclization) results observed for conversion of glutamic acid and pyroglutamic acid were surprising under the acidic or low pH and dilute reagent conditions used, conditions normally favoring ring-opening, not cyclization. While cyclization can be done thermally, the rate for cyclization appears to be surprisingly enhanced in the presence of a hydrogenation catalyst, e.g., a transition metal on a carbon support.
The term “hydrogenation catalyst” as used herein refers to a reduction catalyst. Preferred catalysts include, but are not limited to, ruthenium (Ru), rhenium (Re), rhodium (Rh), platinum (Pt), palladium (Pd), copper (Cu), nickel (Ni), cobalt (Co), molybdenum (Mo), copper chromite, including various oxides and Raney forms thereof. Supports may include carbon (C), niobium (Nb), titania (TiO 2 ), zirconia (ZrO 2 ), silica (SiO 2 ), tin (Sn), alumina (Al 2 O 3 ) or mixtures thereof.
Concentrations for the starting materials are ideally and preferably at the limit of solubility in the reaction solvent. For example, GLU concentration in the starting solvent is in the range of from about 1 to about 30 wt % in H 2 O. More preferably, the starting concentration of GLU in the reaction solvent is in the range from 10 to about 30 wt %. For pyroglutamic acid (PGA), solubility is much greater in the reaction solvent, preferably in the range from 1% to about 70 wt %, with a range from about 10–50 wt % being more preferred, and from 10–30 wt % being most preferred. Solvent choices are myriad including alcohols such as methanol and ethanol, water, carbon dioxide, and non-protio solvents including, but not limited to, cyclohexane, alkanes, ethers, or combinations thereof. Solvents are selected based on the desired end products. Preferred solvents include water, methanol, and mixtures thereof, but are not limited thereto.
The formation of the pyrrolidine class of compounds is significant as cyclization reactions forming pyrrolidinone are representative and illustrative of conversion and formation of many like classes of useful compounds. Formation of pyrrolidines extends the types of products available from cyclization.
Various starting materials comprising various inherent functional groups may be used. For example, cyclization reactions may involve starting materials comprising R-group functionalities where R is selected from hydrogen (e.g., —H), as well as alkyl and aryl groups having carbon numbers in the range from about 1 to about 20, and moieties comprising non-reducing heteroatoms including, but not limited to, O (e.g., as in carbamate formation), and N (e.g., as in urea formation).
It may be undesirable to convert certain amino acid moieties under conditions of low pH as taught in the art. For example, processes of the present invention involving reactions such as cyclization are viewed as being extremely useful for selective conversion of starting materials whereby ringed compounds of varying size are formed. Addition of acid is not required and may promote unexpected or undesirable results. In particular, reducing a carboxylic acid functional group on a substituted lactam does not require use of acid. Addition of acid promotes reduction of the lactam carbonyl leading to a cyclic amine.
As a starting material, aspartic acid is expected to yield an intermediate or end product containing a 4-member ring. GLU yields compounds having a 5-member ring following cyclization. Lysine is expected to yield compounds containing a 7-member ring following cyclization. Ornithine, another similar compound, is also cyclizable. Further, additional and various R-functional groups including, but not limited to, —H, —CH 2 OH, —COOH, and —NH 2 may be added to the cyclized N-reaction products thereby yielding a host of additional and desirable substituted intermediate and end-use products.
In short, the conversion process detailed for GLU and PGA is equally applicable to other amino acids moieties and related compounds including, but not limited to, lysine, aspartic acid, arginine, asparagine, glutamine, ornithine, and substitution products thereof. All conversion products as would be envisioned by the person of ordinary skill in view of the reaction processes of the present invention are hereby incorporated.
Choice of reaction temperature has proven to be important to the process yields, with elevated temperatures being the most useful. For example, reaction temperatures in the range from 30–200° C. are preferred, with a temperature in the range from 125–150° C. being more preferred. Further, a reducing atmosphere with a H 2 partial pressure in the range from about 15 psi to about 3000 psi. For reactions of the present invention involving an acidic medium, a pH of less than or equal to 3 is preferred.
Suitable acids include mineral acids such as hydrochloric (HCl) and sulfuric acid (H 2 SO 4 ), although phosphoric acid (H 3 PO 4 ) is preferred. Other choices for acids include carbon dioxide, carboxylic acids, amino acids, and solid acids, including but not limited to, acidic resins, acid zeolites, and acidic clays. Acidic resins include perfluorinated polymers or copolymers of tetrafluoroethylene and perfluoro-3,6-dioxa-4-methyl-7-octenesulfonyl fluoride, sold commercially under the tradename Nafion® resins (E.I. du Pont de Nemours and Company, 1007 Market Street, Wilmington, Del.). Other workable acid resins include the carboxylated polystyrenes and sulfonated polystyrenes, sold commercially under the tradenames Dowex® (Dow Company, 2030 Dow Center, Midland, Mich.) and Amberlyst® (Rohn and Haas, 100 Independence Mall West, Philadelphia, Pa.). Pyroglutamic acid (PGA) as a conversion product is also a suitable acid as it can catalyze reactions when no additional acid is added. However, at least one equivalent of PGA is generally required as the resulting product, prolinol (PRO), is a strong base that tends to form a salt with PGA. Such salts are unreactive toward metal catalyzed hydrogenation reactions, preventing high conversion of PGA to PGOL. For example, the salt is unreactive toward primary reduction (carboxylic acid to alcohol) or secondary reduction (lactam to imine). Thus to the extent that PGOL is formed, an equimolar amount of PGA is neutralized and does not react making full conversion unlikely.
Under certain conditions, acid-promoted reduction of PGOL to PRO may be undesirable. For example, if the intermediate PGOL is the desired end product, it may be favorable to arrest the reaction process at the formation of the intermediate moiety or alternatively conduct the reaction under different conditions vastly improving the specific product yield. In the absence of acid, as noted previously, PGOL can be favored in a molar ratio of about 6:1 (PGOL: PRO). Processes that achieve even higher selectivities are described hereinafter.
The conversion of starting materials to pyrollidinones under non-acid promoted conditions at higher yields will now be described, according to a further embodiment of the present invention. As illustrated in FIG. 4 a , the process generally comprises: a) providing a starting material, GLU and PGA being representative but not exclusive; b) esterifying the acid functional groups 402 of the starting material using R-functional compounds yielding an esterified precursor material 400 . Esterification is done using methodologies known in the art. R-functional group compounds may be selected from alkylating agents, alcohols (e.g., R—OH) including, but not limited to, methanol, ethanol, and prolinol, alkyl halides, olefins, alkyl compounds (e.g., R—CH 3 ), aryl compounds, and combinations thereof. Esterifying the starting material permits the reduction and conversion reactions to be done under neutral or near-neutral conditions, e.g., in the absence of acid, thereby avoiding additional acid-promoted reactions or unwanted salt formation; c) optionally reacting, e.g., cyclizing, the esterified product yielding an esterified pyrrolidinone 410 , e.g., esterified PGA; d) reducing the pyrrolidinone 410 in the presence of a reduction catalyst 412 to yield a final pyrrolidinone 420 , e.g., PGOL.
Higher product yields may be effected by esterifying the various reaction products. Preferred reaction conditions include: 1) presence of a reduction catalyst including metals such as palladium, platinum, copper, copper chromite, nickel, and cobalt, or alternatively ruthenium, and rhenium, 2) a solvent for preparing the ester including, but not limited to methanol, ethanol, prolinol (product), non-protio solvents such as cyclohexane or other alkanes, and ethers, 3) a reaction temperature preferably in the range from about 10° C. to about 200° C., more preferably in the range from about 50° C. to about 180° C., and most preferably in the range from about 75° C. to 150° C., and 4) a hydrogen partial pressure preferably in the range from about 15 psi to about 3000 psi.
Significance of the instant embodiment is the predicted improvement in the yield of PGOL and its derivatives under non-acid-promoted or neutral pH conditions due to the high conversion of the starting material, i.e., GLU or PGA. Yields are selectively optimized for a desired product, e.g., PGOL.
Alternatively, in the absence of esterification, one may maintain the reactor medium at a controlled pH to achieve the desired conversion product. For example, buffering of the reactor medium containing a starting material such as GLU may be considered in order to maintain neutral pH. However, buffering of GLU is generally not ideal in this situation since the starting material must be in the acid form for reduction to occur.
In another process of the present embodiment illustrated in FIG. 4 b , N-substituted pyrrolidinones may be selectively produced, e.g., 5-hydroxy-1-methyl-2-pyrrolidinone, a potential high-value solvent. As shown in FIG. 4 b , for example, following cyclization forming the pyrollidinone 440 , N-substitution may be effected by addition of alcohol to the reactor with optional removal of water, resulting in conversion to N-alkylated pyrrolidinone 450 . For example, conversion of PGA 440 to N-alkylated PGOL 450 may be achieved. Water may be actively removed by standard techniques known in the art including use of a drying agent or removal as an azeotrope. In a reactor solvent comprised entirely of alcohol (e.g., methanol), substitution of the pyrrolidinones 440 and 440 (or 410 and 420 ) occurs directly yielding the N-substituted (e.g., alkylated) pyrrolidinone 450 .
In general, N-substituted products may be produced using compounds selected from alkylating agents, alcohols, alkyl halides, olefins, carbonates, sulfates, and sulfonates yielding functionalities including, but not limited to, —H, —CH 3 , —OH, —C═O, —COOH, R—CH 3 , R—COOH, -alkyl, -aryl, and -lactam carbonyl.
In FIG. 4 b , a non-esterified starting material 430 may be converted from the zwitterionic form of the material. For example, GLU 430 as a zwitterion is cyclized thermally forming the pyrrolidinone 440 , e.g., PGA. Pyrrolidinone 440 is subsequently converted to an N-substituted pyrrolidinone 450 by reduction in the presence of a reduction catalyst and an alkylating agent (e.g., methanol) yielding the N-alkylated PGOL. R-functional group compounds for substitution may be selected as envisioned by the person of ordinary skill in the art.
In general, preferred conversion of a starting material yielding N-substitution products comprises the steps a) providing a starting material 430 in a solvent at controlled pH, b) esterifying the starting material forming an esterified precursor material (e.g., the ester of GLU 400 ), c) optionally reacting (e.g., cyclizing) the esterified precursor material yielding at least one esterified pyrrolidinone or lactam, and d) reducing at least one esterified functional group of the precursor material in the presence of a reduction catalyst yielding at least one product at high yield, and d) further reacting with an R-functional group compound as discussed herein yields at least one final N-substituted product at high yield, e.g., N-alkylated PGOL 450 .
FIG. 5 a illustrates a general reaction process for conversion of a starting material using carbonyl activation arising from the alpha amino group according to an additional embodiment of the present invention. Acidic functional groups 502 of a starting material may be protected by esterifying the moieties yielding an esterified precursor material 510 . Subsequent and selective reduction in the presence of a reduction catalyst yields the conversion product 520 comprising both a carboxylic acid functional group 512 and alcohol 514 . If the reaction is performed in the presence of an R-functional group compound (R—OH) such as methanol, the acid functional group 512 will remain predominantly esterified. Esterification may be partial or complete. For example, if the reaction is performed in the presence of water, functional group 512 will likely be predominantly a free acid, or alternatively a salt or zwitterion. Temperatures are preferably below about 100° C. whereby esterification of the amino acid activates the alpha carbonyl selectively (i.e., α-amino activation effect) leading to the desired conversion product 520 . Pressures of up to about 3000 psi are preferred, with pressures in the range from about 500 psi to 1500 psi being more preferred.
The esterified moieties may comprise R-functional groups selected from —R—CH 3 , —CH 3 , -lactam carbonyl, —C═O, —R—COOH, —COOH, —R—OH, -alkyl, -aryl, and —H, with carbon numbers for R in the range from about 1 to about 20. Where R=—H, the reaction medium is preferably controlled at a pH near the pl thereby maintaining the starting material in zwitterionic form, e.g., about 3.2–3.5 for GLU.
FIG. 5 b illustrates a complete reaction scheme according to the instant embodiment for conversion of a representative starting material, e.g., GLU. In the starting material, carboxylic acid functional groups of glutamic acid, including the primary C-5 group 530 may be optionally protected initially by esterifying with an R-functional group compound yielding the esterified precursor material 540 , where R is selected from -alkyl, and -aryl moieties with a carbon number in the range from about 1 to about 20. R may also be —H, although greater yields are expected using esterified precursors. Reacting (e.g., cyclizing) the precursor 540 yields an esterified pyrollidinone 550 (a cyclic amide) comprising a lactam carbonyl. Cyclization can be accomplished under thermal conditions in a solvent comprising water, alcohols, or mixtures thereof. Cyclization differentiates the lactam carbonyl preferentially over the carbonyl of the carboxylic acid. Thus, reduction in the presence of a reduction catalyst selectively yields the 5-ol product. Ring opening is effected under excess base conditions.
For GLU as a starting material, temperatures above 100° C. are preferred given that solubility of glutamic acid is 0.8 wt % in water at 25° C. Solubility of GLU increases under elevated temperatures reaching approximately 15 wt % at 100° C. Thus, GLU solutions must be kept warm or precipitation occurs. Cyclization of GLU can also be done in dilute solutions comprising the starting material in water thereby forming pyroglutamic acid (PGA). PGA may also be used as a starting material which is advantageous given its high water solubility. The person of ordinary skill in the art will recognize the potential for conversion of many like starting materials.
In FIG. 5 b , pyrrolidinones 550 and 560 show an N-substitution comprising —H, but are not limited thereto. For example, R-group functionalities as previously described may be substituted. Continued reduction of the esterified pyrrolidinone 550 in the presence of a reduction catalyst results in selective removal of the R-functional ester yielding the -ol form of the pyrrolidinone, e.g., a pyroglutaminol (PGOL) 560 or other N-substituted pyrrolidinone products. The resulting pyrrolidinone comprises both a lactam carbonyl and a free alcohol, e.g., the 6-ol. Base-promoted ring opening yields a five-carbon moiety, e.g., 4-amino-5-ol-pentanoic acid 570, a desirable end product.
In general, selective reduction of one or more carboxylic acid groups of GLU represents a desirable conversion and transformation process for making novel five-carbon compounds, the selective conversion of GLU to 4-amino-5-ol-pentanoic acid being a notable example. Uses for the conversion products include potential applications as polymers, coatings, and adhesives. The reaction scheme illustrated in FIG. 5 b involving esterification is anticipated to increase conversion product yields. For example, highest yields for reaction products during hydrogenation of GLU should be achieved by converting esterified intermediates as described herein.
One of many desirable conversion products of GLU is PGOL. As illustrated in FIG. 5 b , conversion of PGOL to other useful end products comprises ring opening. Ring opening may be effected by adding base to the reactor. Further, in the presence of a base at elevated temperature esterified functionalities protecting the C-5 carboxylic acid group are also removed yielding the free PGOL. The base may be any suitable alkali metal hydroxide, alkaline earth metal hydroxide, basic amine, or other Brönsted or Lewis base. The amount of base can be catalytic or up to an equimolar amount. For example, one molar equivalent of base may be added to the reaction vessel and contents heated for approximately one hour at a temperature in the range from about 20° C. to 200° C., 150° C. being typical. Reactions may be effected in the same reactor vessel or alternatively in a separate reactor. Alternatively, temperatures can be significantly lower, e.g., in the range from 50° C. to 100° C. depending on desired reaction outcomes as discussed previously.
Lewis acids may also be employed to tie up the more acidic amino acid group leaving the less acidic carboxylic acid to be reduced. Preferred Lewis Acids include the chlorides, sulfates, oxides, nitrates, and acetates of tin (Sn) and zinc (Zn). One to two equivalents of the Lewis acid are added to the reaction mixture. Hydrogenation is done using the catalysts and conditions described herein. Conversion products form as salts allowing for improved selective reduction of the pendant acid, for example, at position C-5. Catalyst choices when converting ester forms of the starting materials are preferably selected from Pd, Pt, Ni, Cu, Co, including the oxides and Raney forms thereof. The Lewis acid complex is required to selectively chelate the amine-N and carbonyl (C═O) functional groups, leaving the C-5 or other pendant carboxylic acids available for reduction. Preferred reaction conditions include 1) a temperature in the range from about 50 to about 100° C., the lower temperature being preferred to prevent cyclization, 2) a partial hydrogen pressure of from about 15 psi to 2000 psi, and 3) addition of a Lewis acid at a concentration of from 1 to 2 molar equivalents if the solvent is alcohol or a concentration of from 1 to about 100 equivalents if the solvent is water.
FIG. 6 illustrates a process for selective conversion of an amino acid starting material 610 by selective deactivation to a desirable end product 630 according to a further embodiment of the present invention. Control over the reaction is maintained by selectively deactivating the pendant carboxylic acid functional group while selectively promoting the reduction of the lactam carbonyl functionality. For example, a representative amino acid, GLU 610 can be converted to PGA 620 as described previously, with a subsequent final conversion to proline 630 . The process generally comprises: a) optionally reacting (e.g., cyclizing) the starting material 610 yielding a lactam, a cyclic amide comprising a lactam carbonyl, e.g., PGA 620 , and b) deprotonating the pendant carboxylic acid of the lactam with a base or a Lewis acid allowing for selective reduction of the lactam in the presence of a reduction catalyst yielding PRO 630 . Preferred reduction catalysts include palladium (Pd) and platinum (Pt) given the low propensity to reduce the carboxylic acid functional groups. However, other catalysts are also workable. For example, catalysts that tend to hydrogenate carboxylic acid groups, including Ru or Re, may be employed if weak bases are added to maintain the carboxylate form of the acid, i.e., the non-protonated form. Preferred weak bases include amines, cyclic amines, bisulfates, phosphates, phosphites, acetates, and the like. Lewis acids may also serve the same purpose. Strong bases should not be employed in excess as they lead to ring opening. Catalysts on carbon supports that have been treated to be basic are preferred. Such supports assist in desorbing the strong base proline thereby disfavoring further reduction.
When using a Re or Ru catalyst, Lewis acids are used in excess in the range from about 1 to about 100 equivalents. With other catalysts, the Lewis acid can be employed in catalytic amounts. Thus, preferred catalysts follow in the order Pd, Pt, Rh, Cu, Mo, Co, and lastly Re or Ru.
Reaction temperature is preferably in the range from about 50° C. to about 200° C., with a temperature in the range from about 100° C. to about 150° C. being more preferable. A hydrogen pressure between about 1 to about 10 atm is also preferred. Reaction solvent preferably comprises water, alcohols, or mixtures thereof.
The following examples are intended to promote a further understanding of the present invention. Example 1 demonstrates the hydrogenation of PGA in the presence of an acid to produce PGOL. Examples 2–6 demonstrate hydrogenation reactions involving GLU, PGA, and PRO in the presence of acid. Example 7 demonstrates hydrogenation of PGA in the absence of acid. Examples 8–12 demonstrate conversion of PGOL to PRO in the absence of acid, by precious metal catalysis. Example 13 demonstrates conversion of PGOL to PRO is promoted by acid in the presence of precious metal catalysts resulting in hydrogenation and reduction of the lactam carbonyl occurs. Example 14 demonstrates that conversion of PGOL to form PRO is promoted by acid; in the absence of acid, conversion does not occur. Example 15 demonstrates base promoted ring opening of cyclic amino acids and/or lactams.
EXAMPLE 1
Experimental. A 100 mL reactor 200 was charged with 2 g of a 5% ruthenium-supported-on-carbon powder catalyst (ESCAT™-440, Engelhard Corp., Iselin, N.J.) and 100 mL of a water solution comprising 0.22M PGA (Sigma-Aldrich Corp., St. Louis, Mo.) further comprising 0.29M phosphoric acid diluted from the 85% reagent grade acid (Sigma-Aldrich Corp., St. Louis, Mo.). The catalyst came in pre-reduced form comprising 50% water by weight. The reactor 200 was charged with hydrogen to a pressure of 900 psi and heated to 150° C. Upon reaching the desired temperature the reactor pressure was adjusted to 2,000 psi H 2 . The reaction was allowed to proceed four hours. Samples were taken throughout the run.
Results. The maximum yield of PGOL (47% molar yield) was reached at a conversion of 88% in approximately 1 hour. PGOL was converted to PRO upon further reaction. After 4 hours, conversion of the starting material was complete with approximate product yields of 10% PGOL and 90% PRO.
EXAMPLES 2–6
Experimental. Examples 2–6 followed the same procedure as in Example 1 with changes to either hydrogen pressure or concentration of the starting material. Results are summarized in Table 1 below.
TABLE 1
Conversion results for a starting material in an acidified medium.
Preparation
Reaction Conditions
Starting
Run
Conversion Results
Material
H 3 PO 4
Temp
H 2
Time
Conversion
Selectivity
Selectivity
Example
[0.22 M]
[M]
Catalyst
(° C.)
(Psig)
(Hr)
(Mol %)
PGOL
PRO
2
PGA
0.29
5% Ru/C
150
2000
4
99.8
10
90
3
PGA
0.29
5% Ru/C
150
1000
4
99.6
48
48
4
GLU
0.29
5% Ru/C
150
2000
4
100
14
85
5
PRO
0.29
5% Ru/C
150
1000
3.5
98
nd
98
6
GLU
0.29
5% Ru/C
150
2000
4
98
1
98
Where GLU = Glutamic Acid; PGA = Pyroglutamic acid; PGOL = Pyroglutaminol; PRO = Prolinol (5 HMP); nd = not detected
Results. In general, results showed high conversion of GLU and GLU conversion compounds (e.g., PGA) using precious metal catalysis in the absence of additional acid. Further, results in Table 1 show that in the acidic medium comprising a Ru catalyst, PRO was selectively generated. Generally, the reaction converting PGOL to PRO was slower than the conversion of PGA to PGOL. However, results show a high conversion of starting materials above about 90% and high selectivity for prolinol above about 80%.
EXAMPLE 7
Experimental. A 100 mL reactor 200 was charged with 2 g of a 5% ruthenium-supported-on-carbon powder catalyst (ESCAT™-440, Engelhard Corp., Iselin, N.J.) and 100 mL of a water solution comprising 0.22M PGA (Sigma-Aldrich Corp., St. Louis, Mo.). No acid was added to the reactor. The catalyst was added in pre-reduced form comprising 50% water by weight. The reactor 200 was charged with hydrogen to a pressure of 900 psi and heated to 150° C. Upon reaching the desired temperature the reactor pressure was adjusted to 2,000 psi H 2 . The reaction was allowed to proceed four hours. Samples were taken throughout the run.
Results. The maximum yield of PGOL (63% yield, 76% selectivity) was reached at a conversion of 83% after 1 hour. The primary by-product was PRO. Further reaction time did not lead to a significant increase in either conversion or yield. In the absence of acid, formation of PRO yields a salt with PGA. As a salt, PGA does not hydrogenate. Thus, further conversion does not occur.
EXAMPLES 8–12
Experimental. The reaction 200 was charged as detailed in Example 7, i.e., no added acid, with selective changes to temperature, pressure, or reduction catalyst. Samples were taken throughout the run. Results are summarized in Table 2 below.
TABLE 2
Conversion results for a starting material in a non-acidified solution medium.
Preparation
Reaction Conditions
Starting
Run
Conversion Results
Material
H 3 PO 4
Temp
H 2
Time
Conversion
Selectivity
Selectivity
Example
[0.2 M]
[M]
Catalyst
(° C.)
(Psig)
(Hr)
(Mol %)
PGOL
PRO
8
PGA
0
5% Ru/C
150
2000
4
84
74
25
9
PGA
0
5% Ru/C
150
1000
4
91
85
14
10
PGA
0
5% Rh/C
150
1000
2.5
11
54
32
11
PGA
0
10% Pt/C
150
1000
2.5
12
51
49
12
PGA
0
10% Pd/C
150
1000
2.5
15
39
36
PGA = Pyroglutamic acid; PGOL = Pyroglutaminol; PRO = Prolinol
Results. Results in Table 2 show the ruthenium catalyst to be a preferred for conversion of PGA as the free acid (i.e., non-esterified form), with only low to moderate results in the presence of other catalysts. Selectivity for PGOL decreases with decreases in temperature and pressure.
EXAMPLE 13
Experimental. A 100 mL reactor 200 was charged with 2 g of a 5% ruthenium-supported-on-carbon powder catalyst (ESCAT™-440, Engelhard Corp., Iselin, N.J.) and 100 mL of a water solution comprising 0.22M PGA (Sigma-Aldrich Corp., St. Louis, Mo.) further comprising 0.29M phosphoric acid diluted from the 85% reagent grade acid (Sigma-Aldrich Corp., St. Louis, Mo.). The catalyst came in pre-reduced form comprising 50% water by weight. The reactor was charged with hydrogen to a pressure of 200 psi and heated to 150° C. Upon reaching the desired temperature the reactor pressure was adjusted to 1,000 psi H 2 . The reaction was allowed to proceed for 3.5 hours. Samples were taken throughout the run.
Results. At 1000 psi H 2 , conversion of PGOL to PRO was 98% in 3.5 hours, demonstrating essentially complete conversion to a single product at high yield. Results demonstrate that conversion of PGBL to PRO (via hydrogenation of the lactam) is promoted by acid in the presence of precious metal catalysts.
EXAMPLE 14
Experimental. A 100 mL reactor 200 was charged with 2 g of a 5% ruthenium-supported-on-carbon powder catalyst (ESCAT™-440, Engelhard Corp., Iselin, N.J.) and 100 mL of a water solution comprising 0.22M pyroglutaminol. No acid was added to the reactor. The reactor was further charged with hydrogen to a pressure of 400 psi and heated to 150° C. Upon reaching the desired temperature, the reactor pressure was adjusted to 2,000 psi H 2 . The reaction was allowed to proceed for 3.5 hours. Samples were taken throughout the run.
Results. At 2.5 hours, the major product identified by High-Performance Liquid Chromatography was the starting PGOL, with conversion at less than 5%. No PRO was detected. Results demonstrate conversion of PGOL to PRO is promoted by acid. In the absence of added acid, conversion does not occur.
EXAMPLE 15
Experimental. A 100 mL reactor 200 was charged with 2 g of a 5% ruthenium-supported-on-carbon powder catalyst (ESCAT™-440, Engelhard Corp., Iselin, N.J.) and 100 mL of a water solution comprising 0.22M PGA and 0.44M sodium hydroxide. The reactor was charged with hydrogen to a pressure of 200 psi and heated to 150° C. Upon reaching the desired temperature the reactor pressure was adjusted to 2,000 psi H 2 . The reaction was allowed to proceed for two hours. Samples were taken throughout the run.
Results. Results show that approximately 80% of the PGA was converted to glutamate after only 30 minutes at temperature. 13 C NMR analysis showed no other products formed. Results demonstrate that ring opening can be accomplished by heating in the presence of base. Use of catalysts may not be required for the ring opening reaction. In general, it is expected that strong bases will not promote reduction of lactams.
While the preferred embodiments of the present invention have been shown and described, it will be apparent to those skilled in the art that many changes and modifications may be made without departing from the invention in its true scope and broader aspects. The appended claims are therefore intended to cover all such changes and modifications as fall within the spirit and scope of the invention. | The invention relates to processes for converting amino acids and amides to desirable conversion products including pyrrolidines, pyrrolidinones, and other N-substituted products. L-glutamic acid and L-pyroglutamic acid provide general reaction pathways to numerous and valuable selective conversion products with varied potential industrial uses. | 2 |
FIELD OF THE INVENTION
The present invention pertains to an air bag gas generator with a spontaneous ignition agent which ignites at a temperature that is markedly higher than a normal ambient temperature but substantially lower than the ignition temperature of propellant provided in the gas generator.
BACKGROUND OF THE INVENTION
Such gas generators have been known (cf. U.S. Pat. No. 4,561,675 and DE 39,14,690 A1). At ambient temperatures of about 150° to 200° C., which may occur, e.g., in the case of a fire, the spontaneous ignition agent leads to ignition of the propellant and thus to release of the air bag. The generator housing, which consists, in general, of aluminum or another similar lightweight material, still has sufficient strength at these temperatures. Fragmentation of the housing during the release of the air bag in the case of fire is thus prevented.
According to U.S. Pat. No. 4,561,675 and DE 39,14,690 A1, gun powder, i.e., nitrocellulose, is used as the spontaneous ignition agent, possibly in conjunction with other organic nitro compounds.
An air bag gas generator, including the spontaneous ignition agent, is required to remain able to function over a period of 400 hours under a temperature load of up to 110° C. Such peak temperatures may occur, e.g., during prolonged exposure to direct sunlight. However, nitrocellulose is decomposed during prolonged heating. The requirement is therefore not met by the prior-art spontaneous ignition agents.
SUMMARY AND OBJECTS OF THE INVENTION
It is an object of the present invention is to provide a spontaneous ignition agent for air bag gas generators, which remains stable even during prolonged heating to relatively high temperatures.
According to the invention, an air bag gas generator is provided with a spontaneous ignition agent. The ignition agent ignites at a temperature that is markedly higher than a normal ambient temperature, but is substantially lower than an ignition temperature of propellant positioned in the gas generator. This spontaneous ignition element is formed of a mixture of nitrocellulose, an inorganic oxidizing agent, carbon and possibly another fuel for the inorganic oxidizing agent wherein the percentage of nitrocellulose ranges from 20 to 70 wt. % and the percentage of carbon is at least 3 wt. %. The percentage of nitrocellulose in the spontaneous ignition agent is preferably 30 to 50 wt. %. The percentage of carbon in the ignition agent is preferably 5 to 20 wt. %. The oxidizing agent is an alkali or alkaline earth nitrate, chlorate, perchlorate, or peroxide. The oxidizing agent may also be potassium nitrate and the percentage of potassium nitrate relative to the mixture of potassium nitrate, carbon and other fuel is 7 to 85 wt. %.
Preferably the spontaneous ignition agent is designed as a tablet and the spontaneous ignition agent is arranged on an inside of the combustion chamber housing.
It was found, completely as a surprise, that the above-mentioned requirement is met if carbon and an inorganic oxidizing agent reacting with carbon are added to the nitrocellulose. The percentage of nitrocellulose in the spontaneous ignition agent is 20 to 70 wt. %, preferably 30 to 50 wt. %, and especially ca. 40 wt. %.
Especially alkali nitrates, such as potassium or sodium nitrate, may be used as the inorganic oxidizing agents. Alkali chlorates and perchlorates are also suitable for use as oxidizing agents, as are peroxides, especially alkaline-earth peroxides, such as barium peroxide.
Carbon is of particular significance for the heat stabilization of nitrocellulose in the spontaneous ignition agent according to the present invention. Finely ground carbon, such as charcoal, carbon black, or other carbon-containing, powdered materials may be used as the carbon. The percentage of carbon in the spontaneous ignition agent according to the present invention shall be at least 3 wt. %, but the percentage of carbon is preferably 5 to 20 wt. %, relative to the total weight of the spontaneous ignition agent. Besides carbon, other fuels, which can be brought to react with the inorganic oxidizing agent, e.g., sulfur or organic compounds, such as sugar or cellulose, may also be present in the spontaneous ignition agent.
A spontaneous ignition agent that consists of a mixture of nitrocellulose and sulfur-free black blasting powder, in which the weight ratio of nitrocellulose to sulfur-free black blasting powder ranges from 0.5:1 to 0.8:1, proved to be particularly suitable.
The sulfur-free black blasting powder preferably consists of 70 to 85 wt. % potassium nitrate and 30 to 15 wt. % carbon, and especially of ca. 80 wt. % potassium nitrate and ca. 20 wt. % carbon.
However, it is also possible to use sulfur-containing black blasting powder consisting of ca. 75 wt. % potassium nitrate, 10 wt. % sulfur and 15 wt. % carbon. The spontaneous ignition agent according to the present invention, consisting essentially of a mixture of nitrocellulose, carbon and an oxidizing agent, as well as possibly another fuel for the inorganic oxidizing agent (besides carbon), can be pressed very readily into tablets, pellets, or similar other lumpy bodies, or can be shaped otherwise.
The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference is made to the accompanying drawings and descriptive matter in which preferred embodiments of the invention are illustrated.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings:
FIG. 1 is a diagram showing the weight loss over days according to the invention and according to a comparative example;
FIG. 2 is a cross sectional view showing the positioning of the spontaneous ignition agent according to one embodiment of the invention;
FIG. 3 is a view similar to FIG. 2 showing a different position for the spontaneous ignition agent according to the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention will be explained in greater detail below on the basis of a comparative example and an example according to the invention.
COMPARATIVE EXAMPLE
Monobasic, pure nitrocellulose powder (smokeless propellant powder) was stored in air at 105° C. The weight loss of nitrocellulose was measured daily. The results of these measurements are represented by curve A in the diagram enclosed (FIG. 1).
EXAMPLE
The same nitrocellulose powder as in the Comparative Example was mixed with sulfur-free black blasting powder (with the composition of 80 wt. % potassium nitrate and 20 wt. % carbon) at a ratio of 0.66:1. The mixture was stored in air at 105° C., and the weight loss was measured daily. The results of the measurements are represented by curve B in the enclosed diagram (FIG. 1).
As is apparent from the diagram, the weight loss of pure nitrocellulose (curve A) reached ca. 30% after 15 days (360 hours) and even ca. 50% after 17 days (408 hours) due to the formation of gaseous decomposition products. This means that the ability to function of a gas generator containing nitrocellulose as the spontaneous ignition agent decreases very rapidly. In contrast, a weight loss of only ca. 7% occurred in the spontaneous ignition agent according to the present invention even after heating for 30 days (720 hours) at 105° C. This means that the ability to function of a gas generator containing the spontaneous ignition agent according to the present invention is guaranteed with certainty even after such a long exposure time to a temperature of 105° C.
The spontaneous ignition agent according to the present invention is preferably used in the form of tablets, pellets or in the form of other lumpy bodies. The tablets may be arranged in various places in the gas generator.
Two embodiments of air bag gas generators, in which the spontaneous ignition agent tablets are arranged in different places, will be explained in greater detail below on the basis of the drawing. In the drawing, FIGS. 2 and 3 show sections through two different embodiments of the gas generator in a partial representation.
According to FIG. 2, the gas generator has a central tube 1, around which a toroidal combustion chamber housing 2 filled with propellant pellets 3 extends. An electrical igniter 5 is mounted in the central tube 1 on the igniter support 4, and the igniter 5 extends into a booster charge 6, which is arranged in a sleeve 7. At its front side facing away from the igniter 5, the sleeve 7 is provided with a depression 8, in which the spontaneous ignition agent, designed as, i.e. in the form of, a tablet 9, is arranged. The bottom 10 of the depression 8 is designed as a bursting membrane. The interior of the central tube 1 is connected to the interior of the combustion chamber housing 2 through channels 11.
Spontaneous ignition of the spontaneous ignition material 9 occurs in the case of excessive heating of the combustion chamber housing 2 and of the central tube 1, as a result of which ignition of the booster charge 6 takes place after opening of the bursting membrane 10, and the propellant 3 is thus initiated.
The embodiment of the gas generator according to FIG. 3 differs from that according to FIG. 2 only in that the spontaneous ignition agent, designed as the tablet 9, is attached to the inside of the combustion chamber housing by means of a suitable adhesive 12.
Spontaneous ignition of the spontaneous ignition agent 9 takes place in the case of excessive heating of the combustion chamber housing 2, so that the propellant 3 is ignited. The booster charge 6 and the electrical igniter 5 are also initiated by the combustion of the propellant, so that the gas generator is completely inert after the end of the combustion.
The embodiment according to FIG. 3 with the spontaneous ignition agent tablet arranged on the inside of the combustion chamber housing is especially suitable for long tubular generators as well, because if the spontaneous ignition agent is arranged in such a tubular generator (only) at the igniting unit, which extends axially into the tubular combustion chamber housing from a front side, the spontaneous ignition agent will not be ignited when the combustion chamber housing is heated only on the side facing away from the igniting unit. However, if a plurality of spontaneous ignition agent tablets are attached distributed on the inner wall of the combustion chamber housing, the air bag is released even in the case of only local heating of the housing.
While specific embodiments of the invention have been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles. | A spontaneous ignition agent for an air bag gas generator with excellent temperature resistance comprises essentially nitrocellulose, an inorganic oxidizing agent, and carbon. | 2 |
This application is a continuation of prior application Ser. No. 09/704,968, filed Nov. 2, 2000, now U.S. Pat. No. 6,972,334, incorporated herein by reference to the extent permitted by law.
BACKGROUND OF THE INVENTION
This invention relates to a bathophenanthroline compound, which is adapted for use in an organic electroluminescent device (e.g. an organic electroluminescent device suitable as a display device or a light-emitting device such as a spontaneous light flat display, especially an organic electroluminescent color display using an organic thin film as an electroluminescent layer), and also a process for preparing the compound.
In recent years, importance of interfaces between human beings and machines including multimedia-oriented commercial articles is exalted. For more comfortable and more efficient machine operations, it is necessary to retrieve information from an operated machine without failure simply, instantaneously and in an adequate amount. To this end, studies have been made on various types of display devices or displays.
As machines are now miniaturized, there is an increasing demand, day by day, for miniaturization and thinning of display devices. For instance, there is an inconceivable development with respect to the miniaturization of lap top-type information processors of the all-in-one type such as notebook-size personal computers, notebook-size word processors and the like. This, in turn, entails a remarkable technical innovation on liquid crystal displays for use as a display device for the processor.
Nowadays, liquid crystal displays are employed as an interface of a diversity of articles and have wide utility in the fields not only of lap top-type information processors, but also of articles for our daily use including small-sized television sets, watches, desk-top calculators and the like.
These liquid crystal displays have been studied as a key of display devices, which are used as the interface connecting a human being and a machine and cover small-sized to large capacitance display devices while making use of the feature that liquid crystals are low in drive voltage and power consumption. However, liquid crystal displays have the problems that they do not rely on spontaneous light and thus need a greater power consumption for back light drive than for liquid crystal drive, with the result that a service time is shortened when using a built-in battery, thus placing a limitation on their use. Moreover, the liquid crystal display has another problem that it has such a narrow angle of field as not to be suitable for use as a large-sized display device.
Furthermore, the liquid crystal display depends on the manner of display using the orientation of liquid crystal molecules, and this is considered to bring about a serious problem that its contrast changes depending on the angle even within an angle of field.
From the standpoint of drive systems, an active matrix system, which is one of drive systems, has a response speed sufficient to deal with a motion picture. However, since a TFT (thin film transistor) drive circuit is used, a difficulty is involved in making a large screen size owing to the pixel defects, thus being disadvantageous in view of the reduction in cost.
In the liquid crystal display, a simple matrix system, which is another type of drive system, is not only low in cost, but also relatively easy in making a large screen size. However, this system has the problem that its response speed is not enough to deal with a motion picture.
In contrast, a spontaneous light display device is now under study such as on a plasma display device, an inorganic electroluminescent device, an organic electroluminescent device and the like.
The plasma display device employs plasma emission in a low pressure gas for display and is suited for the purposes of a large size and large capacitance, but has the problem on thinning and costs. In addition, an AC bias of high potential is required for its drive, and thus, the display is not suitable as a portable device.
The inorganic electroluminescent device has been put on the market as a green light emission display. Like the plasma display device, an AC bias drive is essential, for which several hundreds of volts are necessary, thus not being of practical use.
In this connection, however, emission of three primaries including red (R), green (G) and blue (B) necessary for color display has been succeeded due to the technical development. Since inorganic materials are used for this purpose, it has been difficult to control emission wavelengths depending on the molecular design or the like. Thus, it is believed that full color display is difficult.
On the other hand, the electroluminescent phenomenon caused by organic compounds has been long studied ever since there was discovered a luminescent or emission phenomenon wherein carriers are injected into the single crystal of anthracene capable of emitting a strong fluorescence in the first part of 1960s. However, such fluorescence is low in brightness and monochronous in nature, and the single crystal is used, so that this emission has been made as a fundamental investigation of carrier injection into organic materials.
However, since Tang et al. of Eastman Kodak have made public an organic thin film electroluminescent device of a built-up structure having an amorphous luminescent or emission layer capable of realizing low voltage drive and high brightness emission in 1987, extensive studies have been made, in various fields, on the emission, stability, rise in brightness, built-up structure, manner of fabrication and the like with respect to the three primaries of R, G and B.
Furthermore, diverse novel materials have been prepared with the aid of the molecular design inherent to an organic material. At present, it starts to conduct extensive studies on applications, to color displays, of organic electroluminescent devices having excellent characteristic features of DC low voltage drive, thinning, and spontaneous light emission and the like.
The organic electroluminescent device (which may be sometimes referred to as organic EL device hereinafter) has a film thickness of 1 μm or below. When an electric current is charged to the device, the electric energy is converted to a light energy thereby causing luminescence to be emitted in the form of a plane. Thus, the device has an ideal feature for use as a display device of the spontaneous emission type.
FIG. 7 shows an example of a known organic EL device. An organic EL device 10 includes, on a transparent substrate 6 (e.g. a glass substrate), an ITO (indium tin oxide) transparent electrode 5 , a hole transport layer 4 , an emission layer 3 , an electron transport layer 2 , and a cathode 1 (e.g. an aluminium electrode) formed in this order, for example, by a vacuum deposition method.
A DC voltage 7 is selectively applied between the transparent electrode 5 serving as an anode and the cathode 1 , so that holes serving as carriers charged from the transparent electrode 5 are moved via the hole transport layer 4 , and electrons charged from the cathode 1 are moved via the electron transport layer 2 , thereby causing the re-combination of the electrons-holes. From the site of the re-combination, light 8 with a given wavelength is emitted and can be observed from the side of the transparent substrate 6 .
The emission layer 3 may be made of a light-emitting substance such as, for example, anthracene, naphthalene, phenanthrene, pyrene, chrysene, perylene, butadiene, coumarin, acridine, stilbene and the like. This may be contained in the electron transport layer 2 .
FIG. 8 shows another example of an organic EL device. In an organic EL device 20 , the emission layer 3 as in FIG. 7 is omitted and, instead, such a light-emitting substance as mentioned above is contained in the electron transport layer 2 , and thus, the organic EL device 20 is so arranged as to emit light 18 having a given wavelength from an interface between the electron transport layer 2 and the hole transport layer 4 .
FIG. 9 shows an application of the organic EL device. More particularly, a built-up body of the respective organic layers (including the hole transport layer 4 , and the emission layer 3 or the electron transport layer 2 ) is interposed between the cathode 1 and the anode 5 . These electrodes are, respectively, provided in the form of stripes that are intersected in the form of a matrix. In this state, a signal voltage is applied to in time series by means of a luminance signal circuit 34 and a shift register-built in control circuit 35 so that light is emitted at a number of intersected points (pixels), respectively.
Such an arrangement as set out above is usable not only as a display, but also as an image reproducing apparatus. It will be noted that if the striped pattern is provided for the respective colors of R, G and B, there can be obtained a full color or a multi-color arrangement.
In a display device made of a plurality of pixels using the organic EL device, emitting organic thin film layers 2 , 3 and 4 are usually sandwiched between the transparent electrode 5 and the metal electrode 1 , and emission occurs at the side of the transparent electrode 5 .
For use as constituting materials of the organic EL device, attention has now been drawn to organic luminescent materials and carrier transport materials suitable for use in combination with the organic luminescent materials. The advantages of these organic materials reside in that their optical and electrical properties can be controlled to some extent through the molecular design thereof. When an organic luminescent material having a given light emission and a carrier transport material suited therewith are used in combination, efficient light emission is ensured. Accordingly, there can be realized a full color organic EL device wherein primaries of R, G and B are emitted using the respective luminescent materials.
In some case, such an organic EL device as set out above may have such a structure that a hole transport layer serves also as a luminescent element. In this device structure, it is essential to provide a carrier transport layer that is able to efficiently transport electrons and block holes. However, organic materials that satisfy the above requirement and the efficient manufacture of these materials have never been found yet.
SUMAMRY OF THE INVENTION
An object of the invention is to provide a novel organic material, which is suitable for use as a carrier transport material capable of efficiently transporting electrons and blocking holes.
Another object of the invention is to provide a process for preparing such an organic compound as mentioned above in an efficient manner.
According to an aspect of the invention, there is provided a bathophenanthroline compound of the following general formula [I] or [II]
wherein R 1 and R 2 may be the same or different and independently represent a linear, branched or cyclic, saturated or unsaturated hydrocarbon group, or a substituted or unsubstituted, saturated or unsaturated hydrocarbon group provided that at least one of R 1 and R 2 has at least two carbon atoms, or
wherein Ar 1 and Ar 2 may be the same or different and independently represent a substituted or unsubstituted aryl group.
The bathophenanthroline compound of the invention can control carrier transportability depending on the type of substituent introduced into the molecule, and can thus be utilizable as a carrier transport material of various types of organic EL devices. The compounds have high glass transition point and high melting point and are stable electrically, thermally and/or chemically. In addition, the compounds are sublimable in nature, which is advantageous in that a uniform amorphous film can be readily formed according to a vacuum deposition process.
In the bathophenanthroline compounds of the formulas [I] and [II], it is preferred that R 1 and R 2 , and Ar 1 and Ar 2 are, respectively, the same. It will be noted that the term “aryl group” used herein means a carbocyclic aromatic group such as, for example, a phenyl group, a naphthyl group, an anthryl group or the like, and a heterocyclic aromatic group such as, for example, a furyl group, a thienyl group, a pyridyl group or the like.
According to another aspect of the invention, there is also provided a process for perparing a bathophenanthroline compound, which comprising subjecting a lithium compound of the following general formula [III] or [V]
General Formula [III]:
R 3 —Li or R 4 —Li
wherein R 3 and R 4 may be the same or different and independently represent a linear, branched or cyclic, saturated or unsaturated hydrocarbon group or a substituted or unsubstituted, saturated or unsaturated hydrocarbon group provided that at least one of R 3 and R 4 has at least two carbon atoms, or
General Formula [V]:
Ar 3 —Li or Ar 4 —Li
wherein Ar 3 and Ar 4 may be the same or different and independently represent a substituted or unsubstituted aryl group, and bathophenanthroline of the following formula [IV]
to nucleophilic substitution reaction to obtain a bathophenanthroline compound of the afore-indicated formula [I) or [II].
According to the preparation process of the invention, the bathophenanthroline compound of the invention can be efficiently prepared. It is preferred that in the course of the nucleophilic substitution reaction, carbanions are generated from the lithium compound and subsequently reacted with the bathophenanthroline.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic sectional view showing an essential part of an organic EL device using a bathophenanthroline compound of the invention;
FIG. 2 is a schematic band model view showing a built-up structure of the organic EL device;
FIG. 3 is schematic sectional view showing a vacuum deposition apparatus used to make the organic EL device;
FIG. 4 is a plan view showing the organic EL device;
FIG. 5 is a schematic sectional view showing an essential part of another type of organic EL device using a bathophenanthroline compound of the invention;
FIG. 6 is a schematic sectional view showing an essential part of further another type of organic EL device using a bathophenanthroline compound of the invention;
FIG. 7 is a schematic sectional view showing an example of a prior-art organic EL device;
FIG. 8 is a schematic sectional view showing an example of another type of prior-art organic EL device; and
FIG. 9 is a schematic perspective view showing an example of further another type of prior-art organic EL device.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The bathophenanthroline compound of the invention is described in more detail. In the compound of the general formula [I], R 1 and R 2 independently represent a linear, branched or cyclic, saturated or unsaturated hydrocarbon group. Specific examples include an ethyl group, a butyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group, an iso-pentyl group, a neopentyl group, a tert-pentyl group, a cyclopentyl group, an n-hexyl group, a 2-ethylbutyl group, a 3,3-dimethylbutyl group, a cyclohexyl group, an n-heptyl group, a cyclohexylmethyl group, an n-octyl group, a tert-octyl group, a 2-ethylhexyl group, an n-nonyl group, an n-decyl group, an n-dodecyl group, an n-tetradecyl group, an n-hexadecyl group and the like although not limited to those mentioned above.
Specific examples of the substituted or unsubstituted, saturated and unsaturated hydrocarbon group for R 1 and R 2 include a benzyl group, a phenethyl group, an α-methylbenzyl group, an α,α-dimethylbenzyl group, a 1-naphthylmethyl group, a 2-naphthylmethyl group, a 2-methylbenzyl group, a 3-methylbenzyl group, a 4-methylbenzyl group, a 4-ethylbenzyl group, a 4-isopropylbenzyl group, a 4-tert-butylbenzyl group, a 4-n-hexylbenzyl group, a 4-nonylbenzyl group, a 3,4-dimethylbenzyl group, and the like saturated or unsaturated hydrocarbon group although not limited to those mentioned above. R 1 and/or R 2 can also be a furfuryl group.
In the general formula [II], Ar 1 and Ar 2 independently represent a substituted or unsubstituted aryl group. Specific examples include a phenyl group, a 1-naphthyl group, a 2-anthryl group, a 9-anthryl group, a 2-fluorenyl group, a 4-quinolyl group, a pyridyl group, a 3-pyridynyl group, a 2-pyridynyl group, a 3-furyl group, a 2-furyl group, a 3-thienyl group, a 2-oxazolyl group, a 2-thiazolyl group, a 2-benzoxazolyl group, a 2-benzothiazolyl group, a 2-benzothiazoryl group, a 4-methylphenyl group, a 3-methylphenyl group, a 2-methylphenyl group, a 2,3-dimethylphenyl group, a 2,4-dimethylphenyl group, a 2,5 -dimethylphenyl group, a 2,6-dimethylphenyl group, a 3,4-dimethylphenyl group, a, 3,5-diemthylphenyl group, a 2,3,4-trimethylphenyl group, a 2,3,5-trimethylphenyl group, a 2,3,6-trimethylphenyl group, a 3,4,5 -trimethylphenyl group, a 4-ethylphenyl group, a 3-ethylphenyl group, a 2-ethylphenyl group, a 2,3-diethylphenyl group, a 2,4-diethylphenyl group, a 2,5-diethylphenyl group, a 2,6-diethylphenyl group, a 3,4-diethylphenyl group, a 3,5-diethylphenyl group, a 2,3,4-triethylphenyl group, a 2,3,5-triethylphenyl group, a 2,3,6-triethylphenyl group, a 3,4,5-triethylphenyl group, a 4-n-propylphenyl group, a 4-isopropylphenyl group, a 2-isopropylphenyl group, a 4-n-butylphenyl group, a 4-isobutylphenyl group, a 4-sec-butylphenyl group, a 4-tert-butylphenyl group, a 3-tert-butylphenyl group, a 2-tert-butylphenyl group and the like although not limited to those mentioned above.
Specific examples of the bathophenanthroline compound of the invention includes those mentioned below as Compound Nos. 1 to 178, but these compounds should not be construed as limitation thereof. In the specific compounds, Me represents a methyl group, Et represents an ethyl group, Pr represents a propyl group, and Bu represents a butyl group.
Preferred embodiments of the invention wherein bathophenanthroline compounds of the invention are, respectively, applied to an organic EL device are described.
<First Embodiment>
FIG. 1 is a schematic sectional view showing an essential part of an organic EL device capable of emitting blue luminescence according to the first embodiment of the invention.
In this embodiment, a transparent electrode, made of ITO (indium tin oxide) or Zn-doped indium oxide, is formed on a glass substrate 6 by sputtering or vacuum deposition, followed by successively forming a hole transporting luminescent layer 4 a hole transporting luminescent layer 4 b , a hole-blocking layer 33 containing a bathophenanthroline (derivative) compound of the afore-indicated general formula, an electron transport layer 2 , and a cathode electrode 1 in this order according to a vacuum deposition technique to form an organic EL device (organic EL device) 21 made of the amorphous organic thin films.
This organic EL device 21 has such an arrangement that the hole transport layer 4 serves also as a luminescent layer, and this fundamental structure is likewise employed in other embodiments described hereinafter.
The feature of the organic EL device 21 of this embodiment resides in that the bathophenanthroline derivative-containing layer 33 is interposed, as a hole-blocking layer, between the hole transport layer 4 and the electron transport layer 2 , so that the re-combination of electrons-holes is promoted in the hole transport layer 4 , at which luminescence is emitted, and/or luminescence is also emitted from the bathophenanthroline derivative-containing layer 33 .
FIG. 2 schematically shows the built-up structure of the organic EL device of this embodiment in FIG. 1 as a band model.
In FIG. 2 , the thick lines (L 1 , L 2 ) indicated at the cathode 1 made of Al and Al—Li (aluminium-lithium,) and the ITO transparent electrode 5 layer, respectively, mean approximate work functions of the respective metals. In the respective layers between the electrodes, upper thick lines l 1 , l 2 , l 3 and l 4 and numerical values thereof indicate the lowest unoccupied molecular orbital (LUMO) levels, and lower thick lines l 5 , l 6 , l 7 and l 8 and numerical values thereof indicate the highest occupied molecular orbital (HOMO) levels, respectively. It is to be noted that the energy levels in FIG. 2 are shown only by way of example and may widely vary depending on the types of materials.
In the organic EL device, as shown in FIG. 2 , the holes h charged from the transparent electrode 5 serving as an anode are moved via the hole transport layer 4 . On the other hand, electrons e charged from the metal electrode 1 serving as a cathode are moved via the electron transport layer 2 . The electrons-holes are re-combined in the hole transporting luminescent layer, at which luminescence is emitted.
The electrons e charged from the metal electrode 1 serving as a cathode has the tendency of moving toward a lower energy level, and can arrive at the hole transporting luminescent layers 4 b , 4 a via the lowest unoccupied molecular orbital (LUMO) levels l 1 to l 4 of the respective layers in the order of the metal electrode 1 , electron transport layer 2 , hole-blocking layer 33 , hole transporting luminescent layer 4 b and hole transporting luminescent layer 4 a.
On the other hand, the holes h charged from the ITO transparent electrode 5 serving as an anode has the tendency of moving toward a higher energy level, and can move to the electron transport layer 2 via the highest occupied molecular orbital (HOMO) levels l 5 to l 7 of the respective layers in the order of the hole transporting luminescent layer 4 a , hole transporting luminescent layer 4 b and hole-blocking layer 33 .
However, as shown in FIG. 2 , the highest occupied molecular orbital (HOMO) level 1 8 of the electron transport layer 2 is lower in energy than the highest occupied molecular orbital (HOMO) level 1 7 of the hole-blocking layer 33 . This makes it difficult that the charged holes h moves from the hole-blocking layer 33 toward the electron transport layer 2 , and thus, they are filled in the hole-blocking layer 33 .
Eventually, the holes h filled in the hole-blocking layer 33 promote the re-combination of electrons-holes at the hole transport layer 4 , thereby permitting the luminescent materials of the hole transporting luminescent layers 4 a , 4 b or the hole transport layer 4 to emit luminescence or light.
In this way, the provision of the hole-blocking layer 33 effectively controls the transport of the holes h in the hole-blocking layer 33 so that the electron-hole re-combination in the hole transport layer 4 is efficiently caused. Thus, light with a specific wavelength (blue) is emitted in the form of light emission mainly from the hole transporting luminescent layer 4 b , adjoining to the hole-blocking layer 33 , of the light-emitting hole transporting luminescent layers 4 a , 4 b , to which emission from the hole transporting luminescent layer 4 a is added.
Fundamentally, the electron-hole re-combination takes place in the respective layers including the electron transport layer 2 and the hole transport layer 4 as resulting from the charge of electrons from the cathode electrode 1 and the charge of holes from the anode electrode 5 . Accordingly, in the absence of such a hole-blocking layer 33 as set out above, the electron-hole re-combination occurs at the interface between the electron transport layer 2 and the hole transport layer 4 so that light emission with a long wavelength alone is obtained. However, when the hole-blocking layer 33 as in this embodiment is provided, it is enabled to promote blue light emission while permitting the luminescent substance-containing hole transport layer 4 as an emission region.
As set out above, the hole-blocking layer 33 is provided to control the transport of the holes h. To this end, it is sufficient that the highest occupied molecular orbital (HOMO) level of the hole-blocking layer 33 is not higher than the HOMO level that is lower in energy between the HOMO levels of the hole transporting luminescent layer 4 b and the electron transport layer 2 , and that the lowest unoccupied molecular orbital (LUMO) level of the hole-blocking layer 33 is not lower than the LUMO level that is lower in energy and is not higher than the LUMO level that is higher in energy, between the LUMO levels of the hole transporting luminescent layer 4 b and the electron transport layer 2 . Thus, the invention is not limited to such an arrangement as set out before.
In the practice of the invention, the energy levels may not always be within such ranges as defined before, and the bathophenanthroline compound-containing layer per se may emit light or luminescence. In addition, the hole-blocking layer may be made of a built-up structure including a plurality of layers.
The hole-blocking layer 33 may be formed of the bathophenanthroline derivative and/or other material, and its thickness may be changed within a range permitting its function to be maintained. More particularly, the thickness is preferably within a range of 1 Å to 1,000 Å (0.1 nm to 100 nm). If the thickness is too small, the hole blocking ability becomes incomplete, so that the re-combination region is liable to extend over the hole transport layer and the electron transport layer. On the contrary, when the thickness is too large, light emission may not occur due to the increase in film resistance.
The organic EL device 21 is made by use of a vacuum deposition apparatus 11 shown in FIG. 3 . The apparatus 11 has therein a pair of support means 13 fixed below an arm 12 . A stage mechanism (not shown) is provided between the fixed support means 13 so that a transparent glass substrate 6 can be turned down and a mask 22 can be set as shown. Below the glass substrate 6 and the mask 22 , a shutter 14 supported with a shaft 14 a is provided, below which a given number of deposition sources 28 are further provided. The deposition sources are heated by means of a resistance heating system using an electric power supply 29 . For the heating, an EB (electron beam) heating system may also be used, if necessary.
In this apparatus, the mask 22 is for pixels, and the shutter 14 is for deposition materials. The shutter 14 is able to rotate about the shaft 14 a and has the function of intercepting a deposition stream of a material depending on the sublimation temperature of the deposition material.
FIG. 4 is a plan view showing a specific example of the organic EL device fabricated by use of the vacuum deposition apparatus. More particularly, ITO transparent electrodes 5 each with a size of 2 mm×2 mm are vacuum deposited on a glass substrate 6 with a size, L, of 30 mm×30 mm by means of the vacuum deposition apparatus in a thickness of about 100 nm, followed by vacuum deposition of SiO 2 30 over the entire surface thereof and etching in a given pixel pattern to form a multitude of openings 31 . In this way, the transparent electrodes 5 are, respectively, exposed. Thereafter, the respective organic layers 4 , 33 , 2 and a metal electrode 1 are successively formed through a deposition mask 22 of SiO 2 on each 2 mm×2 mm emission region (pixel) PX.
Using the vacuum deposition apparatus 11 , a large-sized pixel may be singly formed, aside from the device having a multitude of pixels as shown in FIG. 4 .
In this way, when the organic layer 33 is formed in order to improve the efficiency of the electron-hole re-combinations in the emission region, there can be obtained an organic EL device that is stable and high in brightness, can be driven at a low voltage and has the hole transporting luminescent layer 4 . As will be described in more detail, it is enabled to obtain a brightness of not smaller than 10,000 cd/m 2 by DC drive and a peak brightness, calculated as DC, of not smaller than 55,000 cd/M 2 by pulse drive at a duty ratio of 1/10 with respect to blue light emission.
The transparent electrode, organic hole transport layer, organic hole-blocking layer, organic electron transport layer and metal electrode of the electroluminescent device may, respectively, have a built-up structure made of a plurality of layers.
The respective organic layers of the electroluminescent device may be formed not only by vacuum deposition, but also other film-forming techniques using sublimation or vaporization, or a technique of spin coating, casting or the like.
The hole transporting luminescent layer of the electroluminescent device may be formed by co-deposition of a small amount of molecules in order to control emission spectra of the device, and may be, for example, an organic thin film containing a small amount of an organic substance such as a perylene derivative, a coumarin derivative or the like.
Usable hole transport materials include, aside from benzidine or its derivatives, styrylamine or its derivatives and triphenylmethane or its derivatives, porphyrin or its derivatives, triazole or its derivatives, imidazole or its derivatives, oxadiazole or its derivatives, polyarylalkanes or derivatives thereof, phenylenediamine or its derivatives, arylamines or derivatives thereof, oxazole or its derivatives, anthracene or its derivatives, fluorenone or its derivatives, hydrazone or its derivatives, stilbene or its derivatives, or heterocyclic conjugated monomers, oligomers, polymers and the like such as polysilane compounds, vinylcarbazole compounds, thiophene compounds, aniline compounds and the like.
More particularly, mention is made of α-naphthylphenyldiamine, porphyrin, metal tetraphenylporphyrins, metal naphthalocyanines, 4,4′,4″-trimethyltriphenylamine, 4,4′,4″-tris(3-methylphenylphenylamino)triphenylamine, N,N,N′,N′-tetrakis(p-tolyl)-p-phenylenediamine, N,N,N′,N′-tetraphenyl-4,4′-diaminobiphenyl, N-phenylcarbazole, 4-di-p-tolylaminostilbene, poly(paraphenylenevinylene), poly(thiophenevinylene), poly(2,2′-thienylpyrrole) and the like, although not limited thereto.
Usable electron transport materials include quinoline or its derivatives, perylene or its derivatives, bistylyl or its derivatives, pyrazine or its derivatives, and the like.
More specifically, mention is made, for example, of 8-hydroxyquinoline aluminium, anthracene, naphthalene, phenanthrene, pyrene, chrysene, perylene, butadiene, coumarin, acridine, stilbene, or derivatives thereof.
The materials used as the anode electrode or cathode electrode of the electroluminescent device are not limitative in types.
The cathode electrode material should preferably be made of a metal whose work function from a vacuum level of an electrode material is small in order to efficiently charge electrons. There may be used, aside from an aluminium-lithium alloy, low work function metals such as, for example, aluminium, indium, magnesium, silver, calcium, barium, lithium and the like, singly or in the form of alloys with other metals for enhancing the stability thereof.
In order to take out organic electroluminescence from the side of the anode electrode, ITO is used as a transparent anode electrode in examples appearing hereinafter. Nevertheless, there may be used electrode materials, which have a great work function from the vacuum level of an anode electrode material and include, for example, gold, a stannic oxide-antimony mixture, a zinc oxide-aluminium mixture or the like, so as to efficiently charge holes.
The substrate 2 may not be limited to a glass substrate, but may be made of an opaque material. More particularly, there may be used, for example, a silicon substrate, a Cr substrate, or a substrate made of glass, on which a metal is formed by vacuum deposition. Where a substrate made of an opaque material is used, it is preferred that the upper surface of an organic EL device (i.e. the side of the cathode electrode) is formed of a transparent or translucent material so that electroluminescence is picked out to outside. ITO may be used for this purpose, for example.
There can be made an organic EL device for full color or multi-color, which is capable of emission of primaries of R, G and B, by proper choice of luminescent materials, not to mention an organic EL device for monochrome. Besides, the organic EL device of the invention is usable not only for display, but also for light source along with its application to other optical. use.
It will be noted that the organic EL device may be sealed with germanium oxide or the like so as to enhance, the stability thereof by suppressing the influence of oxygen or the like in air, or may be driven under conditions drawn to vacuum.
<Second Embodiment>
FIG. 5 is a schematic sectional view showing an essential part of an organic EL device according to a second embodiment of the invention. An organic EL device 22 of this embodiment differs from that of FIG. 1 in that the hole transporting luminescent layer 4 b is formed on the ITO transparent electrode 5 so that the hole transporting luminescent layer is formed as a single layer.
<Third Embodiment>
FIG. 6 is a schematic sectional view showing an essential part of an organic EL device according to a third embodiment of the invention.
An organic EL device 23 of this embodiment differs from that of FIG. 1 in that a hole transport layer (serving also as a hole transporting luminescent layer) 4 a is formed on the ITO transparent electrode 5 , and thus, the hole transporting luminescent layer is formed as a single layer, like the second embodiment.
The invention is more particularly described by way of examples.
EXAMPLE 1
Preparation of 2,9-di(2-methylphenyl)bathophenanthroline
The reaction sequence is shown below
n-Butyl lithium (1.6 M n-hexane solution, 17.0 ml, 26.8 mmol) was gradually dropped in an n-hexane solution (40 ml) of 2-iodotoluene (5.84 g, 26.4 mmol) at room temperature. After completion of the dropping, the reaction solution was agitated at room temperature for 16 hours, and the resultant product was separated by filtration, followed by washing of the resulting white solid with n-hexane (40 ml×3 times). A toluene solution (50 ml) of bathophenanthroline (2.03 g, 6.11 mmol) was gradually dropped, at room temperature, in an anhydrous diethyl ether/toluene (3:1) solution (20 ml) of the resulting white solid, followed by agitation at room temperature for 16 hours.
60 ml of iced water was added to the resultant reaction solution to separate an organic layer therefrom. The aqueous layer was extracted three times with chloroform, and the resultant organic layer was mixed with the previously separated organic layer. 60 g of manganese dioxide (chemically treated product) was added to the thus mixed organic layer and agitated for 30 minutes, after which 100 g of sodium sulfate was further added, followed by agitation for 30 minutes.
The resulting mixed solution was filtered and concentrated, and the residue was purified through column chromatography (silica gel, developing solvent: n-hexan/chloroform 4:1→2:1), followed by recrystallization (solvent for recrystallization: chloroform/n-hexane=2:1) to obtain the intended compound (1.01 g, yield: 49.5%) as light yellow crystals.
The product was identified through 1 H-NMR (solvent: chloroform) and FAB-MS measurements.
1 H-NMR: 2.70 (m, 6H, CH 3 —Ar—), 7.25–7.75 (s, 18H, aromatic), 7.80 (s, 2H, aromatic), 7.90 (s, 2H, aromatic)
MS: m/s (relative intensity) 512 (M + , 100)
The visible light absorption maximum wavelength of a tetrahydrofuran (THF) solution of the product was at 297 nm, with a fluorescent wavelength being at 390 nm.
EXAMPLE 2
Preparation of 2,9-di(2,6-dimethylphenyl)-bathophenanthroline
The reaction sequence is shown below
n-Butyl lithium (1.6 M n-hexane solution, 60.2 ml, 96.3 mmol) was gradually dropped in an n-hexane/anhydrous diethyl ether (10:1) solution (110 ml) of 2-bromo-m-xylene (17.8 g, 96.3 mmol) at room temperature. After completion of the dropping, the reaction solution was heated under reflux for 2 hours and further agitated at room temperature for 16 hours, and the resultant product was separated by filtration, followed by washing of the resulting white solids with n-hexane (50 ml×3 times). A toluene solution (80 ml) of bathophenanthroline (5.09 g, 15.3 mmol) was gradually dropped, at room temperature, in an anhydrous diethyl ether solution (40 ml) of the resulting white solids. After completion of the dropping, the solution was heated under reflux for 2 hours and agitated at room temperature for 16 hours.
60 ml of iced water was gradually added to the resultant reaction solution to separate an organic layer therefrom. The aqueous layer was extracted three times with chloroform, and the resultant organic layer was mixed with the previously separated organic layer. 60 g of manganese dioxide (chemically treated product) was added to the thus mixed organic layer and agitated for 30 minutes, after which 100 g of sodium sulfate was further added, followed by agitation for 30 minutes.
The resulting mixed solution was filtered and concentrated, and the residue was purified through column chromatography (silica gel, developing solvent: n-hexane/chloroform=8:1→4:1), followed by recrystallization (solvent for recrystallization: chloroform/n-hexane=2:1) to obtain the intended compound (2.00 g, yield: 39.4%) as light yellow crystals.
The product was identified through 1 H-NMR and FAB-MS measurements.
1 H-NMR: 2.25 (m, 12H, CH 3 —Ar—), 7.05–7.25 (s, 6H, aromatic), 7.35–7.70 (s, 12H, aromatic), 7.95 (s, 2H, aromatic)
MS: m/s (relative intensity) 540 (M + , 100)
The visible light absorption maximum wavelength of a THF solution of the product was at 286 nm, with a fluorescent wavelength being at 380 nm.
EXAMPLE 3
Preparation of 2,9-dinaphthyl-bathophenanthroline
The reaction sequence is shown below
n-Butyl lithium (1.6 M n-hexane solution, 15.3 ml, 24.4 mmol) was gradually dropped, at 0° C., in an n-hexane/anhydrous diethyl ether (1:1) solution (60 ml) of 1-bromonaphthalene (5.01 g, 24.4 mmol). After completion of the dropping, the reaction solution was agitated at room temperature for 16 hours, and the resultant product was subsequently separated by filtration, and the residue was washed with n-hexane (40 ml×3 times). A toluene solution (80 ml) of bathophenanthroline (2.03 g, 6.11 mmol) was gradually dropped, at room temperature, in an anhydrous diethyl ether solution (40 ml) of the resulting solids. After completion of the dropping, the reaction solution was agitated at room temperature for 16 hours.
60 ml of iced water was gradually added to the resultant reaction solution to separate an organic layer therefrom. The aqueous layer was extracted three times with chloroform, and the resultant organic layer was mixed with the previously separated organic layer. 60 g of manganese dioxide (chemically treated product) was added to the thus mixed organic layer and agitated for 30 minutes, after which 100 g of sodium sulfate was further added, followed by agitation for 30 minutes.
The resulting mixed solution was filtered and concentrated, and the residue was purified through column chromatography (silica gel, developing solvent: n-hexane/chloroform=8:1→4:1), followed by recrystallization (solvent for recrystallization: chloroform/n-hexane=2:1) to obtain the intended compound (1.38 g, yield: 68.2%).
The product was identified through 1 H-NMR and FAB-MS measurements.
1 H-NMR: 7.30–8.00 (s, 24H, aromatic), 8.32 (s, 2H, aromatic), 8.68 (s, 2H, aromatic)
MS: m/s (relative intensity) 584 (M + , 100)
EXAMPLE 4
Preparation of 2,9-difluorenyl-bathophenanthroline
The reaction sequence is shown below
Lithium diisopropylamine (LDA) (1.89 g, 17.4 mmol) was added to a THF solution (30 ml) of fluorene (4.16 g, 25.0 mmol) and agitated at room temperature for 16 hours. Thereafter, the THF and diisopropylamine were removed by distillation under reduced pressure. A toluene solution (60 ml) of bathophenanthroline (2.03 g, 6.11 mmol) was gradually dropped in an anhydrous diethyl ether solution (20 ml) of the resultant yellow solids at room temperature. After the dropping, the reaction solution was heated under reflux for 2 hours and agitated at room temperature for 16 hours.
60 ml of iced water was gradually added to the resultant reaction solution to separate an organic layer therefrom. The aqueous layer was extracted three times with chloroform, and the resultant organic layer was mixed with the previously separated organic layer. 60 g of manganese dioxide (chemically treated product) was added to the thus mixed organic layer and agitated for 30 minutes, after which 100 g of sodium sulfate was further added, followed by agitation for 30 minutes.
The resulting mixed solution was filtered and concentrated, and the residue was purified through column chromatography (silica gel, developing solvent: n-hexane/chloroform=8:1→4:1), followed by recrystallization (solvent for recrystallization: chloroform/n-hexane=2:1) to obtain the intended compound (1.38 g, yield: 68.2%).
The product was identified through 1 H-NMR and FAB-MS measurements.
1 H-NMR: 4.51 (m, 2H, Ar—CH 2 —Ar), 7.30–7.78 (s, 28H, aromatic), 7.81 (s, 2H, aromatic)
MS: m/s (relative intensity) 660 (M + , 100)
EXAMPLE 5
Preparation of 2,9-dibenzyl-bathophenanthroline
The reaction sequence is shown below
n-Butyl lithium ( 1 . 6 M n-hexane solution, 4.45 ml, 7.13 mmol) was gradually dropped in anhydrous toluene (2.24 g, 24.9 mmol) at room temperature. After completion of the dropping, Me-THF (0.627 g, 7.47 mmol) was further added to the solution at −22° C. in 20 minutes. Thereafter, THF (1.06 g, 14.7 mmol) was added to in 30 minutes, followed by agitation at 6 to 10° C. for 16 hours. A toluene solution (40 ml) of bathophenanthroline (2.03 g, 6.11 mmol) was gradually dropped, at room temperature, in the resultant reaction solution. After completion of the dropping, the reaction solution was agitated at room temperature for 16 hours.
60 ml of iced water was gradually added to the resultant reaction solution to separate an organic layer therefrom. The aqueous layer was extracted three times with chloroform, and the resultant organic layer was mixed with the previously separated organic layer. 60 g of manganese dioxide (chemically treated product) was added to the thus mixed organic layer and agitated for 30 minutes, after which 100 g of sodium sulfate was further added, followed by agitation for 30 minutes.
The resulting mixed solution was filtered and concentrated, and the residue was purified through column chromatography (silica gel, developing solvent: n-hexane/chloroform=8:1→4:1), followed by recrystallization (solvent for recrystallization: chloroform/n-hexane=2:1) to obtain the intended compound (0.88 g, yield: 43.3%).
The product was identified through 1 H-NMR and FAB-MS measurements.
1 H-NMR: 4.68 (m, 4H, —CH 2 —Ar), 7.28–7.78 (s, 22H, aromatic), 7.81 (s, 2H, aromatic)
MS: m/s (relative intensity) 512 (M + , 100)
EXAMPLE 6
Preparation of 2,9-dicyclohexyl-bathophenanthroline
The reaction sequence is shown below
n-Butyl lithium (1.6 M n-hexane solution, 36.3 ml, 58.0 mmol) was gradually dropped, at room temperature, in an n-hexane/anhydrous diethyl ether (10:1) solution (50 ml) of chlorocyclohexane (3.00 g, 25.0 mmol). After completion of the dropping, the reaction solution was further agitated at room temperature for 16 hours, and the resultant product was subsequently separated by filtration, and the resulting white solids were washed with n-hexane (50 ml×3 times). A toluene solution (40 ml) of bathophenanthroline (2.03 g, 6.11 mmol) was gradually dropped, at room temperature, in an anhydrous diethyl ether solution (10 ml) of the resulting white solids. After completion of the dropping, the reaction solution was agitated at room temperature for 16 hours.
60 ml of iced water was gradually added to the resultant reaction solution to separate an organic layer therefrom. The aqueous layer was extracted three times with chloroform, and the resultant organic layer was mixed with the previously separated organic layer. 60 g of manganese dioxide (chemically treated product) was added to the thus mixed organic layer and agitated for 30 minutes, after which 100 g of sodium sulfate was further added, followed by agitation for 30 minutes.
The resulting mixed solution was filtered and concentrated, and the residue was purified through column chromatography (silica gel, developing solvent: n-hexane/chloroform=8:1→4:1), followed by recrystallization (solvent for recrystallization: chloroform/n-hexane=2:1) to obtain the intended compound (0.98 g, yield: 48.3%).
The product was identified through 1 H-NMR and FAB-MS measurements.
1 H-NMR: 0.80–2.45 (m, 20H, —CH 2 —CH 2 —CH 2 —CH 2 —CH 2 —), 3.20 (m, 2H, —CH—Ar), 7.25–7.75 (S, 12H, aromatic), 7.81 (s, 2H, aromatic)
MS: m/s (relative intensity) 496 (M + , 100)
EXAMPLE 7
Preparation of 2,9-dibiphenyl-bathophenanthroline
The reaction sequence is shown below
n-Butyl lithium (1.6 M n-hexane solution, 17.0 ml, 27.2 mmol) was gradually dropped, at room temperature, in an n-hexane/anhydrous diethyl ether (10:1) solution (110 ml) of 4-boromobiphenyl (6.33 g, 27.2 mmol). After completion of the dropping, the reaction solution was agitated at room temperature for 16 hours, and the resultant product was subsequently separated by filtration, and the resulting white solids were washed with n-hexane (50 ml×3 times). A toluene solution (40 ml) of bathophenanthroline (2.03 g, 6.11 mmol) was gradually dropped, at room temperature, in an anhydrous diethyl ether solution (20 ml) of the resulting white solids. After completion of the dropping, the reaction solution was agitated at room temperature for 16 hours.
60 ml of iced water was gradually added to the resultant reaction solution to separate an organic layer therefrom. The aqueous layer was extracted three times with chloroform, and the resultant organic layer was mixed with the previously separated organic layer. 60 g of manganese dioxide (chemically treated product) was added to the thus mixed organic layer and agitated for 30 minutes, after which 100 g of sodium sulfate was further added, followed by agitation for 30 minutes.
The resulting mixed solution was filtered and concentrated, and the residue was purified through column chromatography (silica gel, developing solvent: n-hexane/chloroform=8:1→4:1), followed by recrystallization (solvent for recrystallization: chloroform/n-hexane=2:1) to obtain the intended compound (0.76 g, yield: 37.4%).
The product was identified through 1 H-NMR and FAB-MS measurements.
1 H-NMR: 7.25–7.78 (s, 26H, aromatic), 7.81 (s, 2H, aromatic), 8.32 (s, 4H, aromatic)
MS: m/s (relative intensity) 636 (M + , 100)
EXAMPLE 8
Preparation of 2,9-di(2-methylbenzyl)-bathophenanthroline
The reaction sequence is shown below
n-Butyl lithium (1.6 M n-hexane solution, 4.45 ml, 7.13 mmol) was gradually dropped in α-bromo-o-xylene (4.91 g, 24.9 mmol) at room temperature. After completion of the dropping, Me-THF (0.627 g, 7.47 mmol) was added in 20 minutes at −22° C., after which THF (1.06 g, 14.7 mmol) was further added in 30 minutes, followed by further agitation at 6 to 10° C. for 16 hours. A toluene solution (40 ml) of bathophenanthroline (2.03 g, 6.11 mmol) was gradually dropped in the resultant reaction solution at room temperature. After completion of the dropping, the reaction solution was agitated at room temperature for 16 hours.
60 ml of iced water was gradually added to the resultant reaction solution to separate an organic layer therefrom. The aqueous layer was extracted three times with chloroform, and the resultant organic layer was mixed with the previously separated organic layer. 60 g of manganese dioxide (chemically treated product) was added to the thus mixed organic layer and agitated for 30 minutes, after which 100 g of sodium sulfate was further added, followed by agitation for 30 minutes.
The resulting mixed solution was filtered and concentrated, and the residue was purified through column chromatography (silica gel, developing solvent: n-hexane/chloroform=8:1→4:1), followed by recrystallization (solvent for recrystallization: chloroform/n-hexane=2:1) to obtain the intended compound (0.72 g, yield: 35.4%).
The product was identified through 1 H-NMR and FAB-MS measurements.
1 H-NMR: 2.35 (m, 6H, CH 3 —Ar—), 4.65 (m, 4H, CH 2 —Ar—), 7.25–7.78 (s, 20H, aromatic), 7.81 (s, 2H, aromatic)
MS: m/s (relative intensity) 540 (M + , 100)
EXAMPLE 9
Preparation of 2,9-di(8-methylnaphthyl)-bathophenanthroline
The reaction sequence is shown below
n-Butyl lithium (1.6 M n-hexane solution, 15.3 ml, 24.4 mmol) was gradually dropped, at 0° C., in an n-hexane/anhydrous diethyl ether (1:1) solution (60 ml) of 1-bromo-8-methylnaphthalene (5.34 g, 24.4 mmol). After completion of the dropping, the reaction solution was agitated at room temperature for 16 hours, and the resultant product was subsequently separated by filtration, and the residue was washed with n-hexane (40 ml×3 times). A toluene solution (80 ml) of bathophenanthroline (2.03 g, 6.11 mmol) was gradually dropped, at room temperature, in an anhydrous diethyl ether solution (40 ml) of the resulting solids. After completion of the dropping, the reaction solution was agitated at room temperature for 16 hours.
60 ml of iced water was gradually added to the resultant reaction solution to separate an organic layer therefrom. The aqueous layer was extracted three times with chloroform, and the resultant organic layer was mixed with the previously separated organic layer. 60 g of manganese dioxide (chemically treated product) was added to the thus mixed organic layer and agitated for 30 minutes, after which 100 g of sodium sulfate was further added, followed by agitation for 30 minutes.
The resulting mixed solution was filtered and concentrated, and the residue was purified through column chromatography (silica gel, developing solvent: n-hexane/chloroform=8:1→4:1), followed by recrystallization (solvent for recrystallization: chloroform/n-hexane=2:1) to obtain the intended compound (1.30 g, yield: 64.0%).
The product was identified through 1 H-NMR and FAB-MS measurements.
1 H-NMR: 2.60 (m, 6H, CH 3 —Ar—), 7.30–7.81 (s, 22H, aromatic), 7.81 (s, 2H, aromatic), 8.25 (s, 2H, aromatic)
MS: m/s (relative intensity) 612 (M + , 100)
EXAMPLE 10
Preparation of 2,9-di (2-methylnaphthyl)-bathophenanthroline
The reaction sequence is shown below
n-Butyl lithium (1.6 M n-hexane solution, 15.3 ml, 24.4 mmol) was gradually dropped, at 0° C., in an n-hexane/anhydrous diethyl ether (1:1) solution (60 ml) of 1-boromo-2-methylnaphthalene (5.34 g, 24.4 mmol). After completion of the dropping, the reaction solution was agitated at room temperature for 16 hours, and the resultant product was subsequently separated by filtration, and the residue was washed with n-hexane (40 ml×3 times). A toluene solution (80 ml) of bathophenanthroline (2.03 g, 6.11 mmol) was gradually dropped, at room temperature, in an anhydrous diethyl ether solution (40 ml) of the resulting solids. After completion of the dropping, the reaction solution was agitated at room temperature for 16 hours.
60 ml of iced water was gradually added to the resultant reaction solution to separate an organic layer therefrom. The aqueous layer was extracted three times with chloroform, and the resultant organic layer was mixed with the previously separated organic layer. 60 g of manganese dioxide (chemically treated product) was added to the thus mixed organic layer and agitated for 30 minutes, after which 100 g of sodium sulfate was further added, followed by agitation for 30 minutes.
The resulting mixed solution was filtered and concentrated, and the residue was purified through column chromatography (silica gel, developing solvent: n-hexane/chloroform=8:1→4:1), followed by recrystallization (solvent for recrystallization: chloroform/n-hexane=2:1) to obtain the intended compound (1.20 g, yield: 59.1%).
The product was identified through 1 H-NMR and FAB-MS measurements.
1 H-NMR: 2.80 (m, 6H, CH 3 —Ar—), 7.25–7.78 (s, 24H, aromatic), 7.81 (s, 2H, aromatic)
MS: m/s (relative intensity) 612 (M + , 100)
EXAMPLE 11
Preparation of 2,9-di(α-methylbenzyl)-bathophenanthroline
The reaction sequence is shown below
n-Butyl lithium (1.6 M n-hexane solution, 4.45 ml, 7.13 mmol) was gradually dropped in 1-bromo-1-phenylethane (4.91 g, 24.9 mmol) at room temperature. After completion of the dropping, Me-THF (0.627 g, 7.47 mmol) was added in 20 minutes at −22° C., after which THF (1.06 g, 14.7 mmol) was further added in 30 minutes, followed by further agitation at 6 to 10° C. for 16 hours. A toluene solution (40 ml) of bathophenanthroline (2.03 g, 6.11 mmol) was gradually dropped in the resultant reaction solution at room temperature. After completion of the dropping, the reaction solution was agitated at room temperature for 16 hours.
60 ml of iced water was gradually added to the resultant reaction solution to separate an organic layer therefrom. The aqueous layer was extracted three times with chloroform, and the resultant organic layer was mixed with the previously separated organic layer. 60 g of manganese dioxide (chemically treated product) was added to the thus mixed organic layer and agitated for 30 minutes, after which 100 g of sodium sulfate was further added, followed by agitation for 30 minutes.
The resulting mixed solution was filtered and concentrated, and the residue was purified through column chromatography (silica gel, developing solvent: n-hexane/chloroform=8:1→4:1), followed by recrystallization (solvent for recrystallization: chloroform/n-hexane=2:1) to obtain the intended compound (0.83 g, yield: 40.9%).
The product was identified through 1 H-NMR and FAB-MS measurements.
1 H-NMR: 2.40 (m, 6H, CH 3 —Ar—), 4.64 (m, 2H, —CH—Ar—), 7.25–7.78 (s, 22H, aromatic), 7.81 (s, 2H, aromatic)
MS: m/s (relative intensity) 540 (M + , 100)
As will be appreciated from the foregoing, the bathophenanthroline compounds of the invention can control, for example, carrier transportability depending on the type of substituent to be introduced into the molecule, thus permitting one to utilize them as a carrier transport material of various types of organic EL devices. Moreover, these compounds have high glass transition point and melting point and are thus stable electrically, thermally and/or chemically. In addition, the compounds are sublimable in nature, thus leading to the advantage that they are be readily formed as a uniform amorphous film according to a vacuum deposition process. The bathophenanthroline compound of the invention can be efficiently prepared through nucleophilic substitution reaction using an organolithium compound. | A novel bathophenanthroline compound of the general formula [I] or [II] is provided
wherein R 1 and R 2 may be the same or different and independently represent a linear, branched or cyclic, saturated or unsaturated hydrocarbon group, or a substituted or unsubstituted, saturated or unsaturated hydrocarbon group provided that at least one of R 1 and R 2 has at least two carbon atoms, and wherein Ar 1 and Ar 2 may be the same or different and independently represent a substituted or unsubstituted aryl group. A process for preparing the compound is also provided wherein bathophenanthroline and an organolithium compound are subjected to nucleophilic substitution reaction to obtain the compound of the above formula [I] or [II]. | 8 |
BACKGROUND
[0001] Cosmetic materials such as those used for cosmetic foundation are typically provided as a compacted or a loose powder. Loose materials, including loose powder, are becoming more common due in part to the fact that loose material provides improved coverage of the material on a surface. The loose material may be provided in a container with a perforated surface or sifter so that the powder is shaken out of the perforations and the powder can be applied onto an applicator. This configuration is problematic in that the loose material has a tendency to move up through the perforations during handling and/or jostling of the container, such as the movements associated with carrying the container in a handbag, pocket, or purse. The loose material may deposit above the perforated surface and/or on the cap and may at least partially spill out when the container is opened.
SUMMARY
[0002] This disclosure relates to containers usable for holding and dispensing, among other things, powdered or powder-like cosmetics products. According to one exemplary implementation, a container is disclosed that has a bottom portion, a bottom sifter, a dial sifter and a removable cover having pins. The cover has a radially extending top portion, and an axially extending side wall portion. The bottom sifter is engaged with the bottom portion and has at least one sifting hole for sifting materials with a powder-like consistency. The dial sifter is rotatably engaged with the bottom sifter and has at least one sifting hole to align with the at least one sifting hole in the bottom sifter. In an implementation, either the surface of the bottom sifter facing the dial sifter or the surface of the dial sifter facing the bottom sifter has at least one raised portion, and the remaining surface has at least one recessed depression. In other implementations, neither surface of the dial sifter, or the bottom sifter, or both sifters may have a raised portion or a recessed depression. When present, the raised portion and the recessed depression operate to inhibit the dial sifter from rotating relative to the bottom sifter, and to align the sifting holes in the dial sifter and the bottom sifter when the container is open. The upper surface of the dial has one or more axially extending cavities to align and engage axially protruding pins in the cover. When the cover is rotated, the axially protruding pins extend into the axially extending cavities on the dial surface. The dial may rotate with the rotation of the cover, such that when the cover is rotated into a closed position the dial is rotated in relation to the bottom sifter to offset the holes in the bottom sifter and the holes in the dial. When the cover is rotated into an open position the dial is rotated in relation to the bottom sifter to align the holes in the bottom sifter with the holes in the dial.
[0003] According to another exemplary implementation, a container is disclosed that is configured to be filled from the bottom of the container. This implementation includes a container having a top portion, an open bottom portion, a rotating sifter mechanism engaged with the top portion, a cover for enclosing the top portion, and a bottom cap for enclosing the open bottom portion. The rotating sifter mechanism includes a bottom sifter and a dial sifter, the dial sifter being engaged with the cover. Material may be supplied to the open bottom portion. The bottom cap is then affixed to the open bottom portion to enclose the material within the container.
BRIEF DESCRIPTION OF THE DRAWINGS
[0004] FIG. 1 shows an exploded view of a container having a rotating dial sifter, according to one exemplary implementation.
[0005] FIG. 2 shows an elevational view of the container of FIG. 1 .
[0006] FIG. 3 shows a top plan view of the container of FIG. 1 .
[0007] FIG. 4 shows a cross-sectional view of the container of FIG. 1 , taken along line 4 - 4 in FIG. 3 .
[0008] FIG. 5 shows a cross-sectional view of the container of FIG. 1 , taken along line 4 - 4 in FIG. 3 and in which an elastomer layer is sandwiched between the bottom sifter and dial.
[0009] FIG. 6 shows a perspective view of the underside of the cover for the rotating sifter of FIG. 1 .
[0010] FIG. 7 is an exploded view of a container according to another exemplary implementation, having a rotating sifter mechanism including a bottom sifter and a dial, and a bottom cap for enclosing the bottom portion of the container.
[0011] FIG. 8 shows a cross-sectional view of the container of FIG. 7 .
[0012] FIG. 9 is an exploded view of a container according to another exemplary implementation, having a rotating sifter mechanism including a bottom sifter and a dial, the bottom sifter being integral with a bottom portion of the container, and a bottom cap for enclosing the bottom portion of the container.
[0013] FIG. 10 shows a cross-sectional view of the container of FIG. 9 .
[0014] FIG. 11 is a flow diagram showing an exemplary process to fill a container with powder via an opening in the bottom of the container. The order in which the method is described is not intended to be construed as a limitation, and any number of the described method blocks may be combined in any order to implement the method, or an alternate method.
DETAILED DESCRIPTION
[0015] Containers having rotating sifter mechanisms will now be described with reference to the figures. While the disclosure is described in the context of sifters for powdered cosmetics products, they may be useful for other powdered or powder-like products, such as baby powder, foot powder, medicinal powders, and the like.
[0016] FIGS. 1-6 show a container 110 including a cover 112 and a bottom portion 114 . As shown in the exemplary implementation shown in FIG. 1 , the container 110 is provided with a bottom sifter 116 engaged with the bottom portion 114 . A dial sifter 118 is engaged with the bottom sifter 116 . The bottom sifter 116 has at least one hole 120 for sifting loose material, such as facial powder, makeup, or the like stored within a cavity 122 in the bottom portion 114 . The dial sifter 118 has at least one hole 124 , which is capable of aligning with the holes 120 in the bottom sifter 116 . Thus, a user may access the powder by at least slightly inverting the container 110 to sift the loose material through the holes 120 and 124 when they are aligned.
[0017] In this exemplary implementation, the surface of the bottom sifter 116 facing the dial sifter 118 has at least one raised portion 126 , which may be a co-molded thermoplastic elastomer (TPE), centrally aligned with each of the at least one sifting hole 120 in the bottom sifter 116 . The surface of the dial sifter 118 facing the bottom sifter 116 has at least one recessed depression 128 centrally aligned with each of the at least one hole 124 in the dial sifter 118 . The at least one raised portion 126 on the bottom sifter 116 is capable of engaging the at least one recessed depression 128 in the dial sifter 118 , thus aligning and maintaining alignment of the at least one hole 120 in the bottom sifter 116 with the at least one hole 124 in the dial sifter 118 while in an open position. Alternatively, the at least one raised portion 126 on the bottom sifter 116 is capable of engaging the at least one recessed depression 128 in the dial sifter 118 , thus offsetting and maintaining offset of the at least one hole 120 in the bottom sifter 116 with the at least one hole 124 in the dial sifter 118 while in a closed position. The tension associated with the engagement of the at least one raised portion 126 with the at least one recessed depression 128 is overcome by a predetermined force in order to release the engagement of the at least one raised portion 126 with the at least one recessed depression 128 , to rotate or change the position of the dial sifter 118 relative to the bottom sifter 116 during opening or closing of the container 110 . The engagement may reduce inadvertent alignment or misalignment of the dial sifter 118 and the bottom sifter 116 caused by, for example, incidental force or contact.
[0018] The implementation described above is exemplary only and is not intended to be limiting. For example, the at least one raised portion 126 may be provided on the dial sifter 118 and the at least one recessed depression 128 may be provided on the bottom sifter 116 . In another alternative implementation, the at least one raised portion 126 may be aligned in an offset or eccentric manner relative to the at least one sifting hole in the sifter, or with respect to the surface of the sifter. Additionally, the at least one raised portion 126 may have any shape such as a teardrop shape, an offset oval, or the like. In such an instance, the alignment and shape of the at least one recessed depression on one sifter may correspond to the alignment and shape eccentricities of the corresponding at least one raised portion on the other sifter, resulting in secure engagement of the sifters. Further, the at least one recessed depression may have a hollow cylindrical form, allowing it to securely engage with multiple possible shapes of raised portions on the opposite sifter. Moreover, the recessed depression may be provided at the end of a pedestal 129 extending axially away from the surface of the dial sifter 118 . This creates a flush contact between the dial sifter 118 and the bottom sifter 116 even if the two sifters have different surface contours. In alternate implementations, neither surface of the dial sifter 118 , or the bottom sifter 1 16 , nor both sifters may have a raised portion 126 or a recessed depression 128 .
[0019] The container 110 is provided with a mechanism to rotate the dial sifter 118 in relation to the bottom sifter 116 so that the sifting holes 120 and 124 are aligned when the container 110 is “open” to allow a user to access the powder. When the container 110 is “closed,” the sifting holes 120 and 124 are rotated out of alignment, which prevents powder from traveling from the bottom portion 114 through the bottom sifter 116 and the dial sifter 118 . In order to rotate the dial sifter 118 while opening or closing the container 110 , the dial sifter 118 has at least one axially extending cavity 130 in the surface facing away from the bottom portion 114 . The cover 112 has at least one axially protruding pin 132 , shown in FIG. 6 , which extends into the at least one cavity 130 on the surface of the dial sifter 118 . The at least one pin 132 extends into the at least one cavity 130 during a rotation of the cover 112 to close the container. The at least one pin 132 engages with the at least one cavity 130 , thus rotating the dial sifter 118 with the rotation of the cover 112 .
[0020] The bottom sifter 116 is secured or fixed to the bottom portion 114 by friction, glue, threaded engagement, or other suitable means. As shown in FIG. 1 , ribs 134 or other contoured features may additionally provide a surface for maintaining the bottom sifter 116 in the bottom portion 114 . The bottom sifter 116 is positioned to retain loose material within cavity 122 .
[0021] The dial sifter 118 is secured to the bottom sifter 116 by friction or other suitable means. The dial sifter 118 may additionally be secured to the bottom sifter 116 by a pin 136 protruding from the center of the surface of the dial sifter 118 facing the bottom sifter 116 . The pin 136 extends through a hole 138 in the center of the bottom sifter 116 , as shown in FIG. 4 . The pin 136 may be have a hollow center 136 a for convenience of manufacturing, and may have a flange, or a cap 136 b located and/or affixed to the end of the pin 136 to secure the dial sifter 118 in place. Additionally or alternatively, one or more ribs 140 on the bottom sifter 116 may be configured to engage with one or more grooves 142 in the dial sifter 118 . The groove 142 shown in FIG. 1 is a circular groove, gap, slot, or the like along the outer circumference of the dial sifter 118 .
[0022] The dial sifter 118 has a rim portion 144 that extends around the upper surface of the dial sifter 118 . At least one axial cavity 130 is positioned along the rim portion 144 . Additionally, there is a guide channel 146 positioned along the surface of the rim portion 144 , concentric to the circumference of the dial sifter 118 . The guide channel 146 intersects the at least one cavity 130 . The at least one pin 132 , which may be a polypropylene material, is configured to be axially protruding from the cover 112 to extend into the guide channel 146 when the cover 112 is positioned. During rotation of the cover 112 , the at least one pin 132 is guided along the guide channel 146 and may be in a spring-compression state caused by the deflection of the at least one pin 132 toward the cover 112 and one or more spring members 133 toward the pin 132 . In the spring-compression state, the at least one pin 132 may experience a higher level of compression than when the cover 112 is not engaged with the dial sifter 118 . Further rotation of the cover 112 allows the at least one pin 132 to encounter and engage the at least one cavity 130 , thus releasing at least a portion of the spring compression on the at least one pin 132 , extending it into the at least one cavity 130 , and rotatably securing the cover 112 directly to the dial sifter 118 . Rotation of the cover 112 thus rotates the dial sifter 118 . Additionally, the cover 112 has a threaded portion 148 , shown in FIG. 6 , which engages with a threaded portion 150 on the bottom portion 114 of the container 110 .
[0023] In an exemplary implementation, the dial sifter 118 has a hollow, sloped, or concave surface 152 on the side of the dial sifter 118 facing away from the bottom sifter 116 , i.e., the surface facing upward from the bottom portion 114 . This surface 152 assists in directing powder or other material into the at least one hole 124 and, thus, into the loose material holding cavity 122 . This hollowed or sloped surface 152 reduces the amount of powder or other material above the dial sifter 118 when the container 110 is held in an upright position, such as when a user is preparing to close the container 110 . Reducing the amount of powder above the dial sifter 118 and maintaining the holes 120 and 124 in an offset configuration while the cover is closed reduces the amount of powder that may be spilled while the container 110 is closed or when the container 110 is initially opened. In other implementations, the dial sifter 118 does not have a hollow, sloped, or concave surface 152 on either side.
[0024] The cover 112 has a sealing layer 154 engaged with the cover 112 for pressing or touching the dial sifter 118 to further prevent the unintentional spillage of powder from the container 110 . Additionally, there may be a ring-shaped gasket 156 between the dial sifter and the bottom sifter to prevent material from leaking around the sifters.
[0025] As shown in FIG. 5 , the dial sifter 118 may be provided with an elastomeric layer 158 , which may be a co-molded thermoplastic elastomer (TPE). The elastomeric layer 158 is formed on the side of the dial sifter 118 facing the bottom sifter 116 and may deform and seal any gap between the bottom sifter 116 and the dial sifter 118 , particularly in the vicinity of the holes 120 and 124 . The elastomeric layer 158 may alternatively be provided on the bottom sifter 118 on the side facing the dial sifter 118 .
[0026] The bottom portion 114 , bottom sifter 116 , dial sifter 118 , and cover 112 may be constructed of polypropylene, polyethylene, other plastic, glass, wood, or other suitable material and may be molded or formed according to conventional methods. The sealing layer 154 may be waxed paperboard, Teflon, or other suitable material.
[0027] FIGS. 7 and 8 show a variation of the container shown in FIGS. 1-6 , in which the bottom portion has a bottom cap. More particularly, the container 710 has a bottom portion 714 which includes a container wall portion 714 a and a bottom cap 714 b. The bottom cap 714 b allows a user to load powder into the loose material holding cavity 722 of the container after assembling the container 710 . This is accomplished by a process of inverting the assembled container 710 , filling the bottom portion 714 with powder, and affixing the bottom cap 714 b . The bottom cap 714 b is secured to the bottom wall portion 714 a by friction, glue, threaded engagement, and/or other suitable engagement means. Ribs 715 may assist in maintaining engagement of the bottom cap 714 b with bottom wall portion 714 a.
[0028] FIGS. 9 and 10 show a variation of the container shown in FIGS. 7-8 , in which the sifter and bottom portion are integral and the bottom portion has a bottom cap. More particularly, the container 910 has a bottom portion 914 which includes a container wall portion 914 a, an integral sifter 916 , and a bottom cap 914 b. The bottom cap 914 b allows a user to load powder into the loose material holding area 922 of the container after assembling the container 910 . This is accomplished by a process of inverting the assembled container 910 , filling the bottom portion 914 with powder, and affixing the bottom cap 914 b. The bottom cap 914 b is secured to the bottom wall portion 914 a by friction, glue, threaded engagement, and/or other suitable engagement means. Ribs 915 may assist in maintaining engagement of the bottom cap 914 b with bottom wall portion 914 a.
[0029] FIG. 11 shows an exemplary process 1100 for filling a container with powder via an opening in the bottom of the container. The order in which the method is described is not intended to be construed as a limitation, and any number of the described method blocks may be combined in any order to implement the method, or an alternate method. At 1102 , the user determines whether the bottom sifter is configured as a distinct component. If the bottom sifter is determined to be a distinct component, rather than integral to the bottom portion of the container, then the distinct bottom sifter is secured to the bottom portion of the container at 1104 . At 1106 , the container is assembled by engaging the dial sifter with the bottom sifter. At 1108 , the cover is engaged with the dial sifter and the bottom portion, with the cover placed in the closed position. At 1110 , the user positions the container so that the open bottom portion faces toward a filling mechanism. The filling mechanism supplies material, such as facial powder, to the open bottom portion at 1112 . At 1114 , the bottom cap is secured to the bottom wall portion to enclose the material within the container.
[0030] Although details of specific implementations and embodiments are described above, such details are intended to satisfy statutory disclosure obligations rather than to limit the scope of the following claims. Thus, the claims are not limited to the specific features described above. | Described herein are containers having a bottom portion, a bottom sifter, a dial sifter, and a removable cover having pins. A bottom sifter and a dial sifter are rotatably engaged, and both have at least one sifting hole for sifting materials with a powder-like consistency. Either the surface of the bottom sifter facing the dial sifter or the surface of the dial sifter facing the bottom sifter may have at least one raised portion, and the remaining surface may have at least one recessed depression. The dial sifter may have one or more cavities to engage the pins in the cover, thereby rotating the dial with the rotation of the cover. | 0 |
FIELD OF THE INVENTION
The present invention generally relates to a method and system for balancing resource utilization in a cluster of resources, and more specifically, to assigning related service requests to a specific resource to efficiently process the service requests.
BACKGROUND OF THE INVENTION
The term “load balancing” as used in connection with a computer network is a method of dividing work between two or more computational resources so that more work is completed in less time. In general, all clients of a service or services performed by such resources are served more quickly when the computational load is balanced among multiple resources. Typically, a cluster of resources is formed when balancing a computational load. For example, companies whose Web sites receive a great deal of traffic usually use clusters of Web server computers for load balancing.
Load balancing among a cluster of resource nodes is typically done by distributing service requests and service processing throughout the cluster of resources, without any regard for grouping. The goal is to share the processing task among the available resource nodes. Doing so minimizes turn-around time and maximizes resource utilization. In most cases, the particular resource that accepts and processes a service request is irrelevant to a requesting client or to the resources that carry out a service request. For example, it is generally irrelevant which Web server, in a cluster of Web servers, processes a request by a client for a current stock quote.
There are several important considerations in implementing load-balanced systems, including routing of tasks, fault tolerance, node priority, and load distribution. At a system level, controlling the overall load-balancing function involves tasks such as: (1) determining how client requests should be communicated throughout a cluster of resources (i.e., routing); (2) determining the status of resources within a cluster; (3) determining how a load will be handled if one of the resource nodes that was handling that load fails (i.e., fault tolerance); and (4) determining how the cluster will be reconfigured to share the processing load when the number of available resource nodes changes.
At a performance level, it is important to determine when and how a load will be distributed within a cluster. This decision is typically defined in accord with a load distribution algorithm. Typical algorithms of this type include: (1) round robin, (2) weighted round robin, (3) least connections, and (4) statistical mapping. In some load-balancing systems, a centralized control implements the algorithm and effects the load balancing among resources as defined by the algorithm. For example, if two Web servers are available to handle a work load, a third server may determine the Web server that will handle the work (i.e., control routing of service tasks).
This function is often the case with Domain Name System (DNS) load-balancing systems, such as Cisco System, Inc.'s DistributedDirector™. A client simply issues a request to connect to a domain name site, such as www.microsoft.com. This request is routed to a DNS server, which selects the appropriate Web server address. The manner in which the DNS server selects a Web server address is determined by a specific load-distribution algorithm implemented in the DNS server. Once determined, the Web server address is returned to the client, which then initiates a connection request to the Web server address. Thus, the DNS server is the central controller of the load-balancing system that directs traffic throughout the cluster.
To avoid redirecting the client and requiring a second connection request, some hardware load balancers use a centralized technique called Network Address Translation (NAT). NAT is often included as part of a hardware router used in a corporate firewall. NAT typically provides for the translation of an Internet Protocol (IP) address used within one network known as the “outside network” (such as the Internet) to a different IP address employed within another network known as the “inside network” (such as a local area network comprising a cluster of resources). As with a DNS server, NAT devices typically have a variety of load-balancing algorithms available to accomplish dynamic mapping, including round robin, weighted round robin, and least connections.
NAT can also be used in conjunction with policy routing. Policy routing is a routing technique that enables network administrators to distribute traffic among multiple paths based on the traffic characteristics. Instead of simply routing based upon the destination address, policy-based routing enables network administrators to determine and implement routing policies to allow or deny paths in accord with parameters such as the identity of a particular end system, the application requested, the protocol used, and the size of data packets.
Another approach to balance client requests employs a content-smart switch. Like NAT devices, content-smart switches are typically a form of router inserted between clients and Web servers. These switches typically use tags from a client's HTTP request, or use information from cookies stored on the client to determine the Web server to which the client request will be relayed. For example, if a client request tag or cookie identifies the client as a “premium” customer, then the switch will route the client to a Web server that is reserved for premium customers. However, if a cluster of Web servers are reserved for premium clients, then other techniques must still be used to balance the load of premium clients among the cluster of reserved Web servers.
Central load-balancing control is easy to implement and maintain, but is not inherently fault-tolerant and usually requires backup components. In each example above, a backup DNS server, NAT device, and content-smart switch would be required for each corresponding cluster to continue operating if the primary controller failed. Conversely, distributed load-balancing control provides redundancy for fault tolerance, but it requires coordination between the resources in a cluster. Each resource must be aware of the load on the other resources and/or on the cluster as a whole to be capable of managing the load, if necessary.
Distributed load-balancing control can be implemented in hardware, but usually still requires backup components. In contrast, software load-balancing systems can be distributed among each node in the cluster. Although each node must use some of its resources to coordinate the load-balancing function, distributed software load balancing eliminates the cost of, and reliance on, intermediary hardware. Alternatively, distributed software load balancing among each node can be used in addition to intermediary routers/balancers.
Popular software load-balancing systems include Microsoft Corporation's WINDOWS NT™ Load Balancing Service (WLBS) for WINDOWS NT™ Server Enterprise Edition, and the corresponding upgrade version, called Network Load Balancing (NLB), which is a clustering technology included in the WINDOWS™ 2000 Advanced Server and Datacenter Server operating systems. Both use a fully distributed software architecture. For example, an identical copy of the NLB driver runs on each cluster node. At each cluster node, the driver acts as a filter between the node's network adapter driver and its Transmission Control Protocol/Internet Protocol (TCP/IP) stack. A broadcast subnet delivers all incoming client network traffic to each cluster node, which eliminates the need to route incoming packets to individual cluster nodes. The NLB driver on each node allows a portion of the incoming client network traffic to be received by the node. A load-distribution algorithm on each node determines which incoming client packets to accept. This filtering of unwanted packets is faster than routing packets (which involves receiving, examining, rewriting, and resending). Thus, NLB typically delivers higher network throughput than central control solutions.
In conjunction with control of the load-balancing function, load-distribution algorithms determine the distribution of loads throughout a cluster. Unsophisticated algorithms may do nothing more than distribute load by sequentially routing incoming client requests to each successive resource node (i.e., a round robin technique). More generally, a round robin algorithm is a centralized method of selecting among elements in a group in some rational order, usually from the top of a list to the bottom of the list, and then starting again at the top of the list. Another application of the round robin technique is in computer microprocessor operation, wherein different programs take turns using the resources of the computer. In this case, execution of each program is limited to a short time period, then suspended to give another program a turn (or “time-slice”). This approach is referred to as round robin process scheduling.
By extension to Internet server farms, a Round Robin Domain Name System (RRDNS) enables a limited form of TCP/IP load balancing. As suggested by the above description of the DNS server model, RRDNS uses DNS to map incoming IP requests to a defined set of servers in a round robin fashion. Thus, the load balancing is accomplished by appropriate routing of the incoming requests.
Other algorithms for implementing load balancing by distributed routing of incoming requests include weighted round robin, least connections, and random assignment. As the name suggests, weighted round robin simply applies a weighting factor to each node in the list, so that nodes with higher weighting factors have more requests routed to them. Alternatively, the cluster may keep track of the node having the least number of connections to it and route incoming client requests to that node. The random (or statistical) assignment method distributes the requests randomly throughout the cluster. If each node has an equal chance of being randomly assigned an incoming client request, then the statistical distribution will tend to equalize as the number of client requests increases. This technique is useful for clusters that must process a large number of client requests. For example, NLB uses a statistical distribution algorithm to equalize Web server clusters.
Some of the above-noted algorithms may be enhanced by making distribution decisions based on a variety of parameters, including availability of specific nodes, node capacity for doing a specific type of task, node processor utilization, and other performance criteria. However, each of the above-described systems and algorithms considers each client request equally, independent from other client requests. This manner of handling independent requests, and the nodes that service them, is referred to as “stateless.” Stateless resource nodes do not keep track of information related to client requests, because there is no ongoing session between the client and the cluster. For example, an individual Web server, in a cluster of Web servers that provide static Web pages, does not keep track of each client making a request so that the same client can be routed again to that particular Web server to service subsequent requests.
However, it is not uncommon for clusters to provide some interactive service to clients and retain information related to a client request throughout a client session. For example, many clusters servicing E-commerce maintain shopping cart contents and Secure Socket Layer (SSL) authentication during a client session. These applications require “stateful nodes,” because the cluster must keep track of a client's session state. Stateful nodes typically update a database when serving a client request. When multiple stateful nodes are used, they must coordinate updates to avoid conflicts and keep shared data consistent.
Directing clients to the same node can be accomplished with client affinity parameters. For example, all TCP connections from one client IP address can be directed to the same cluster node. Alternatively, a client affinity setting can direct all client requests within a specific address range to a single cluster node. However, such affinities offset the balance of the load in a cluster. In an attempt to maintain as much load balance of client requests as possible while maintaining stateful client sessions on a node, often, a first-tier cluster of stateless nodes are used to balance new incoming client requests, and a second-tier cluster of stateful nodes are used to balance the ongoing client sessions. Also, a third-tier cluster is often used for secure communication with databases. For example, E-commerce Web sites typically use NLB as a first-tier load-balancing system, in conjunction with Component Object Module Plus (COM+) on the second tier, and Microsoft™ Cluster Service (MSCS) on the third tier.
However, the above systems still consider each client request independent from the requests of all other clients. In some cases, there is a need to group certain requests and concomitant processing services, and maintain the group during the processing, even though the requests originate from different clients. For example, in online multi-player computer games, such as Hearts, it is beneficial to direct a number of client game players to a common node and process the game service requested by those clients on that node throughout the entire play of the game. Doing so increases the speed and likelihood of matching interested client players together in a game and maintains continuity of game play. If players are not directed to a common node, one or two players will be left waiting to play at several different nodes when these individuals could already be involved in playing the game if they had been directed to a single node. Also, keeping a group of players together on a single resource or node eliminates delays that would be caused if the processing of the game service for those players is shared between different nodes in the cluster.
Although the need to group players on a single resource is important, it remains desirable to balance the overall processing load represented by all groups of players and various game services (or other processing tasks) being implemented by a cluster among the nodes of the cluster to most efficiently utilize the available processing resources. It is also desirable to be able to scale the load and tolerate faults by dynamic changes to the number of resources in the cluster. Microsoft™ Corporation's Gaming Zone represents a cluster of nodes in which multiple players must be allocated in groups that achieve such a desired balance between different available processing nodes. Previous load-balancing hardware and software techniques have not provided for grouping client requests for a related task on a specific resource node. Accordingly, a technique was required that would both group such related tasks and still balance the overall processing load among all available resource nodes on a cluster.
SUMMARY OF THE INVENTION
The present invention satisfies the need to group and retain clients on a common resource so long as the processing service they require is provided, while distributing the processing load among resources to achieve efficient utilization of the resources in a cluster. In the present invention, a hybrid of stateless and stateful load balancing is employed, using distributed software for decentralized control, and an integrated distribution algorithm for determining the resource that will process client requests. For relatively light traffic, the present invention eliminates the need for multi-tier load-balancing systems, and for high traffic, reduces the number of first-tier stateless nodes required by doing preliminary load balancing on new incoming client requests.
More specifically, the present invention is directed to a method and system for distributing a processing load among a plurality of service resources in a cluster. A cluster may be either a single node implementing multiple instances of a service resource, or multiple nodes, wherein each node can implement multiple instances of different service resource types. Similarly, a service resource may comprise an individual process, such as a single instance of a computer game, or may comprise an entire node that is executing multiple processes, such as a Server. Thus, as used in the claims that follow, the terms “cluster,” “node,” and “resource” are defined in relative terms, but are not limited to a specific hardware or other fixed configuration. As used herein, a cluster includes a plurality of service resources, and the plurality of service resources may be executed on one or more nodes.
The method directs initial connection requests from clients to a single entry-point service resource in the cluster, called an intake. A separate intake is designated for each different type of service that is being provided by the cluster. One or more instances of each type of service are processed by one or more nodes in the cluster. Clients are grouped together and processed in a group at a service resource for as long as the service is provided by the resource. As used herein, a client may be a single client device, such as a personal computer. However, the term client is not intended to be limiting. For example, a client may also be an instance of a function, such as a browser. Thus, multiple instances of a function may run on a single computer, and each instance can be considered an individual client. This may be the case where multiple instances of a browser are run on one personal computer to play a game in multiple groups, or different games, concurrently.
As a function of loading, a first service resource that was designated as the intake determines that another service resource in the cluster should become a new intake for subsequent connection requests from clients. The other service resource is then designated as the new intake. New client requests for the service are then directed to the new intake to form a second group of clients. The second group of clients will continue to receive services from the second service resource for as long as the service is provided.
Designating a service resource as the intake is preferably done by calculating a rating value for each service resource in the cluster, and then selecting the service resource to be the new intake as a function of the rating value. The selected service resource broadcasts a message to the rest of the resources in the cluster, informing the other resources of its identity as the new intake. Any service resource that later receives a request for service from a new client will then direct the new client to the new intake for that service. The client may simply be given a network address to the new intake and required to initiate a connection to the new intake. Alternatively, the client's connection request may be forwarded directly to the new intake.
To distribute the work load throughout the cluster, the service resource that is designated as the current intake first evaluates its own operating conditions to calculate a load value. If the load value exceeds a predetermined threshold, then the intake selects another service resource to be designated as the new intake. The selection is preferably made based on the load value described above. After selecting a new service resource, the current intake service resource broadcasts a message to all other service resources identifying the new intake. The newly designated intake recognizes its new function and accepts connection requests from new clients.
As a fault tolerance measure, a service resource will assume the designation as the new intake if that service resource has not received a status message from the current intake within a predetermined period of time. If more than one service resource assumes the designation as the new intake, then the service resource that will be designated as the new intake is based upon a numerical identifier associated with each of the service resources.
Another aspect of the present invention is directed to a machine-readable medium on which are stored machine-executable instructions that, when executed by a processor, cause the processor to perform functions that are generally consistent with the steps of the method described above. A machine readable medium may store machine instructions executed by the cluster of resources, or machine instructions executed by the clients, or both.
Yet another aspect of the present invention is directed to a system for distributing work load in a cluster. The system comprises at least one processor for implementing the cluster. Although multiple processors may be more commonly used for a cluster, the system can be implemented and used to balance the load among a plurality of resources (e.g., software objects) executed by a single processor, or by multiple processors, to provide services to a plurality of clients. The system further comprises an interface coupling the processor(s) to the clients. A plurality of service resources are operatively connected to each other and to the clients. Each resource is capable of being designated as an intake that accepts new client requests for a specific service, forming a group of clients that will continue to receive services from the service resource for as long as the services are provided. Machine instructions are stored in a memory that is accessible by the one or more processors. The machine instructions cause the one or more processors to implement functions generally consistent with the steps of the method discussed above.
BRIEF DESCRIPTION OF THE DRAWING FIGURES
The foregoing aspects and many of the attendant advantages of this invention will become more readily appreciated as the same becomes better understood by reference to the following detailed description, when taken in conjunction with the accompanying drawings, wherein:
FIG. 1 is a schematic block diagram of an exemplary Server (PC) system suitable for implementing the present invention;
FIG. 2 illustrates the architecture of a preferred embodiment of the present invention in which a cluster of Servers host online game services;
FIG. 3 illustrates the logic of one preferred embodiment for a client device that is connecting to the intake for a specific game type in the cluster of FIG. 2 ;
FIG. 4 illustrates the logic of one preferred embodiment for providing a proxy service to manage client connections to a node in the cluster;
FIG. 5A illustrates a portion of the load-balancing logic employed on each node in the cluster for handling User Datagram Protocol (UDP) messages; and
FIG. 5B illustrates a portion of the load-balancing logic employed on each node in the cluster for handling load distribution and fault tolerance.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Exemplary Operating Environment
FIG. 1 and the following discussion are intended to provide a brief, general description of a suitable computing environment in which the present invention may be implemented, preferably in regard to a server that stores and provides Web pages and a client that requests the Web pages and displays them to a user. Although not required, the present invention will be described in the general context of computer-executable instructions, such as program modules that are executed by a computer configured as a Server, and by client computing devices, such as personal computers. Generally, program modules include routines, programs, objects, components, data structures, etc. that perform particular tasks or implement particular abstract data types. Also, those skilled in the art will appreciate that the present invention may be practiced to balance requests from other client computing devices, including hand-held devices, pocket personal computing devices, digital cell phones adapted to connect to a network, microprocessor-based or programmable consumer electronic devices, game consoles, TV set-top boxes, multiprocessor systems, network personal computers, minicomputers, mainframe computers, industrial control equipment, automotive equipment, aerospace equipment, and the like. The invention may be practiced in a single device with one or more processors that process multiple tasks, but preferably will be practiced in distributed computing environments where tasks are performed by separate processing devices that are linked by a communications network. In a distributed computing environment, program modules may be located in both local and remote memory storage devices.
With reference to FIG. 1 , an exemplary system for implementing the present invention includes a general purpose computing device in the form of a conventional Server 20 , provided with a processing unit 21 , a system memory 22 , and a system bus 23 . The system bus couples various system components, including the system memory, to processing unit 21 and may be any of several types of bus structures, including a memory bus or memory controller, a peripheral bus, and a local bus using any of a variety of known bus architectures. The system memory includes read-only memory (ROM) 24 and random access memory (RAM) 25 . A basic input/output system (BIOS) 26 , containing the basic routines that are employed when transferring information between elements within Server 20 and during start up, is stored in ROM 24 . Server 20 further includes a hard disk drive 27 for reading from and writing to a hard disk (not shown), a magnetic disk drive 28 for reading from or writing to a removable magnetic disk 29 , and an optical disk drive 30 for reading from or writing to a removable optical disk 31 , such as a CD-ROM or other optical media. Hard disk drive 27 , magnetic disk drive 28 , and optical disk drive 30 are connected to system bus 23 by a hard disk drive interface 32 , a magnetic disk drive interface 33 , and an optical disk drive interface 34 , respectively. The drives and their associated computer-readable media provide nonvolatile storage of computer-readable machine instructions, data structures, program modules, and other data for Server 20 . Although the exemplary environment described herein employs a hard disk, removable magnetic disk 29 , and removable optical disk 31 , it will be appreciated by those skilled in the art that other types of computer-readable media, which can store data that is accessible by a computer, such as magnetic cassettes, flash memory cards, digital video disks, Bernoulli cartridges, random access memories (RAMs), read-only memories (ROMs), and the like, may also be used in the exemplary operating environment.
A number of program modules may be stored on the hard disk, magnetic disk 29 , optical disk 31 , ROM 24 , or RAM 25 , including an operating system 35 , one or more application programs 36 (such as a browser program), other program modules 37 , and program data 38 . An operator may enter commands and information into Server 20 through input devices such as a keyboard 40 and a pointing device 42 . Other input devices (not shown) may include a microphone, joystick, game pad, satellite dish, scanner, digital camera, or the like. These and other input devices are often connected to processing unit 21 through an input/output (I/O) device interface 46 that is coupled to the system bus. Output devices, such as a printer (not shown), may also be connected to processing unit 21 through an I/O device interface 46 that is coupled to the system bus. Similarly, a monitor 47 or other type of display device is also connected to system bus 23 via an appropriate interface, such as a video adapter 48 , and is usable to display Web pages and/or other information. In addition to the monitor, Servers may be coupled to other peripheral output devices (not shown), such as speakers (through a sound card or other audio interface—not shown).
Server 20 preferably operates in a networked environment using logical connections to one or more additional computing devices, such as to a cluster node 49 that is yet another server in a cluster of servers. Cluster node 49 is alternatively a database server, a mainframe computer, or some other network node capable of participating in cluster processing, and typically includes many or all of the elements described above in connection with Server 20 , although only an external memory storage device 50 has been illustrated in FIG. 1 . The logical connections depicted in FIG. 1 include a local area network (LAN) 51 and a wide area network (WAN) 52 . Such networking environments are common in offices, enterprise-wide computer networks, and intranets. Preferably, LAN 51 is a back-end subnet connecting a plurality of resource nodes of the cluster in communication with each other. Preferably, WAN 52 is the Internet, which connects the cluster in communication with a plurality of client computers 55 a , 55 b , etc.
Those skilled in the art will recognize that LAN 51 and WAN 52 can be the same network with both resource nodes and client computers connected via only a single network. Client computers 55 a , 55 b , etc. each preferably include many of the elements described above in connection with Server 20 . However, as indicated above, client computers 55 a , 55 b , etc. may be a combination of hand-held devices, pocket personal computing devices, digital cell phones, and other types of client computing devices.
Server 20 is connected to LAN 51 through a cluster network interface or adapter 53 , and to WAN 52 though a client network interface or adapter 54 . Client network interface 54 may be a router, modem, or other well-known device for establishing communications over WAN 52 (i.e., over the Internet). Those skilled in the art will recognize that cluster network interface 53 and client network interface 54 may be internal or external, and may be the same, or even a single interface device. Cluster network interface 53 and client network interface 54 are connected to system bus 23 , or may be coupled to the bus via I/O device interface 46 , e.g., through a serial or other communications port.
In a networked environment, program modules depicted relative to Server 20 , or portions thereof, may be stored in the remote memory storage device. It will be appreciated that the network connections shown are exemplary and other techniques for establishing a communications link between the computers may be used, such as wireless communications.
Exemplary Implementation of the Present Invention
The following describes exemplary implementations of several preferred embodiments. FIG. 2 illustrates the architecture of one preferred embodiment of the invention wherein a cluster of Servers host online game services.
Cluster 100 generally comprises multiple nodes, such as node 102 and node 104 . Each node is operatively connected in communication with clients via a wide area network, such as the Internet 106 , and operatively connected to a local area network, such as back-end subnet 108 . Each node can host multiple types of online game such as Hearts, Checkers, Spades, Backgammon, and Reversi.
Each type of game will typically be implemented in multiple instances on the game service. For example, Hearts has multiple instances identified as Hearts game services 110 aa , 110 ab , etc. Similarly, Checkers has multiple instances implemented as Checkers game services 112 aa , 112 ab , etc. Each game service thus supports multiple instances of the game for that game service. For example, Hearts game service 110 aa might support two hundred games of Hearts, each match including four players. However, to simplify FIG. 2 , each game service is illustrated as representing only one match. Also, each type of game may not have equivalent numbers of game service instances. Some nodes may not provide services for a particular type of game at all. The number of game service instances on a node for a particular type of game typically is indicative of the number of clients requesting that game. For illustrative purposes, node 104 has Hearts game services 110 ba and 110 bb , as well as Checkers game services 112 ba and 112 bb , reflecting that a sufficient number of clients requested Hearts and Checkers to warrant multiple instances of each game service.
To manage client communications with the game services, each node in the cluster implements its own proxy service, as illustrated by proxy services 114 a and 114 b , and the proxy services for the nodes are all identical in functionality. Each proxy service also accesses a dynamic link library (DLL) that comprises a load balancer as illustrated by dynamic link libraries 116 a and 116 b.
A single instance of the proxy service and load balancer could control communication and load balancing for the entire cluster if all client and game service communications were routed to the single proxy service and load balancer, respectively. Such an approach would provide a centralized control embodiment of the present inventions. Preferably, however, a proxy service and a load balancer run on each node to provide fault-tolerant distributed control. Each proxy service manages TCP connections to Internet 106 . Multiple TCP connections 118 aa , 118 ae , 118 ah , 118 ba , etc. are thus illustrated. These TCP connections enable communication between client devices (not shown) and the various instances of the game services.
The proxy service on each node maintains connections with some clients for a short time, although those clients may not currently be communicating with a game service. For example, TCP connection 118 ae represents a client connection in which the client dropped out of Hearts game service 110 ab , but wanted to be matched with a new set of players for another game. The remaining players may continue playing if the game service involved supports artificial intelligence, so that the game service provides a “computer player” as a replacement. After dropping out of Hearts game service 110 ab , the player at TCP connection 118 ae continues to communicate with proxy service 114 a to find out which node has a new Hearts game service that the player can join, and proxy service 114 a will direct the player to Hearts game service 110 bb for a new match. Similarly, the player on TCP connection 118 ah dropped out of Hearts game service 110 ab , but reconnected to Checkers game service 112 aa.
The game services maintain User Datagram Protocol (UDP) communication with load balancer 116 . UDP connections 120 aa , 120 ba , etc. convey various status messages from each game service to the corresponding node's load balancer. Each load balancer 116 maintains UDP connections 122 a , 122 b , etc., using back end subnet 108 .
One game service instance of each type of game is designated as an “intake” for the cluster. The intake for a specific type of game serves as a central point for new client requests and groups, or matches, clients into a game. For example, Checkers game service 112 aa is designated as the Checkers intake 124 for the Checkers game type. Similarly, Hearts game service 110 bb is designated as the Hearts intake 126 for the Hearts game type. Any game service instance can be designated the intake for that game type regardless of which node within the cluster is executing the designated game service instance. However, only one game service instance can be designated as the intake for each type of game. A game service instance that is designated as the intake for a game type is responsible for accepting new client requests to participate in that type of game.
FIG. 3 illustrates the logic of a preferred embodiment that facilitates the connection of a client device to the intake of a type of game provided on a cluster like that described above. Although the present invention does not require the client device to have any special capabilities or to store communication addresses to games hosted by the cluster, one preferred embodiment incorporates additional capabilities and provides addresses accessed by the operating systems of the client devices to automate connecting to and communicating with the cluster. For example, the Microsoft WINDOWS™ Millennium Edition Operating System includes a list of DNS names and associated IP addresses of cluster nodes in Microsoft Corporation's MSN GAME ZONE™, which are configured to run the game types discussed above. Thus, when a user selects a type of game on the client device that the user wants to play online, the operating system picks the corresponding DNS name and an associated IP address to initiate communication with the cluster so that the user can play the selected game.
As illustrated by a step 150 , the client device attempts to connect to the selected game IP address in the cluster. At a decision step 152 , the client device determines whether the connection attempt has failed. If so, then the client device determines at a decision step 154 whether additional IP addresses that correspond to other nodes in the cluster for the selected game type are stored on the client device. If an additional IP address is available for the selected game type, the client device returns to step 150 to attempt to connect to the new IP address. If no additional IP addresses are available for the selected game type, then the client device retrieves a generic IP address for the cluster from its list of DNS names. A generic IP address is registered to the general DNS name of the cluster, which has all nodes in the cluster registered to it. Thus, even if only one node in the cluster remains functional, the client will eventually find it. The client then attempts to connect to the generic IP address at a step 156 . At a decision step 158 a client device determines whether this connection has failed. If so, the client device determines at a decision step 160 whether any additional generic IP addresses to the cluster are stored on the client device. If so, the client device again attempts to connect to the cluster at the new generic IP address via step 156 . If no additional generic IP addresses are available, then the connection attempts are ended, and a notice of the failure is provided to the user.
Once a communication connection is established between the client device and the cluster via the Internet, the client device makes a request to participate in the selected game type at a step 162 . If the IP address of the node in the cluster to which the client device has connected is not the node hosting the game instance currently designated as the intake for the selected game type (sometimes referred to as the intake node), the client device will receive the correct IP address for the node in the cluster that is hosting the game instance designated as the intake for the selected game. At a decision step 164 , the client device determines whether it has been given a different IP address for redirecting the client device to the correct node currently designated as the intake for the requested game. If the client device receives a new IP address, the client device redirects connection with the client to the new intake address at a step 166 . The client device then monitors the communication to detect any failure at a decision step 168 . If the communication connection fails at this point, then the client device again attempts to establish communication with one of the IP addresses associated with the DNS name for the selected game at step 150 . If, however, the client device successfully connects to the new intake IP address, the client device again requests game service at step 162 .
As long as the client device is not redirected again because the intake moved before the client device's game request was received, the client device has connected to the current intake for the selected type of game and will not be redirected at decision step 164 . The client device then waits at a step 170 for a match to be made with other client devices requesting the same selected game. If, while waiting for a match, communication is disconnected between the client device and the intake, the client device detects the disconnection at a decision step 172 . If communication is disconnected, the client device receives the most recent intake address for the selected game and a disconnection notice from the cluster at a step 174 . If no interruption occurs in the communication, and sufficient other client devices are connected to the intake for the selected game, a match is formed by that intake and the selected game is played at a step 176 .
While the game is being played, at a decision step 178 , the client device monitors the communications to detect any interruption in the game service or in the communication with the cluster. If communication is disconnected, the service fails, or the game finishes, then the client device receives the IP address for the current intake and a disconnect notice from the cluster at a step 180 . At a step 182 , the client device then displays a notice to the user indicating that the game has terminated and requesting whether the user wishes to play the game again. If so, the client device attempts to connect to the new IP address at step 166 . If the user does not wish to play another game, the process ends.
The user may also terminate the game while connected to the cluster. The client device detects an indication that the user wishes to exit the game at a decision step 184 . If the user has elected to exit, the process ends. However, if the user does not indicate any desire to end the game, the game continues for as long as the same group of matched client players continues to play the game at step 186 and an interruption in communications does not occur. If the group of matched client players disbands, but the user wishes to continue playing the same game type, then the client device is directed to the current intake for the selected type of game in order to be rematched into a new game. The client device requests to be disconnected from the current game service at a step 190 , which enables the client device to receive the IP address for the current intake of the selected game type at step 174 . Reconnection to the current intake then proceeds as described above.
On the cluster side of this process, FIG. 4 illustrates the logic implemented by a proxy service in a preferred embodiment, to manage client connections with a node in the cluster. At a step 200 , the proxy service accepts an initial TCP connection from a client. The proxy service then waits for a game request from the client at a step 202 . At a decision step 204 the proxy service determines whether the client connection has been dropped. If so, the service to that client comes to an end.
However, if the proxy service successfully receives a game request without the connection being dropped, then at a step 206 , the proxy service requests an address of the intake for the requested game type. The proxy service makes this request to the load balancer component of the proxy service on the local node executing the proxy service. When the proxy service receives an intake address from the load balancer, at a decision step 208 , the proxy service determines whether the intake address is on the local node (i.e., the node on which the proxy service is executing) or on a remote node. If the intake address is not on the local node, then the proxy service sends a message to the client at a step 210 , including the IP address of the node with the intake for the requested game type. The proxy service then disconnects from the client at a step 212 , ending its service to this client.
Once the client connects to the node with the intake for the requested game type, the local proxy service of that node establishes a TCP connection to the intake at a step 214 . The intake matches the client with other waiting clients for an instance of the requested game. This function is considered a stateful connection, because the same game service continues to service this group of clients who are playing in a game instance, until the game is completed, the game is prematurely terminated, or the connection is interrupted. Thus, at a step 216 , the proxy service passes messages between the same game service and the client throughout the game session for that client. While the game session continues, the proxy service determines whether the client has dropped out of the session at a decision step 218 . If so, the service to that client is terminated.
While the client remains in the game session, the proxy service also determines whether the game session has been prematurely dropped at a decision step 220 . A game session may be dropped if another client drops out of the game and the game instance does not permit an artificial intelligence game player (i.e., the computer) to take over. The game session may also be dropped if the game session fails, the node is removed from the cluster, or if other interruptions occur.
If a game interruption occurs, the proxy service again requests the load balancer for the current intake address of the selected game type at a step 222 . When the proxy service receives the intake address from the load balancer, the proxy service sends a message to the client at a step 224 , notifying the client that the game is over, and providing the client with the current intake address. At a decision step 226 , the proxy service determines whether the current intake address corresponds to a local game service (i.e., on the same node as the proxy service). If the current intake for the selected game is on the local node, the proxy service returns to step 202 to wait for the client to request another game. However, if the current intake for the selected game is on a remote node, the proxy service disconnects the client at a step 212 , requiring the client to reconnect to the node designated as the current intake for the game selected by the client.
While the game is in session, the proxy service monitors to determine if the client has requested a new instance of the same type of game at a decision step 228 . So long as no such request is made, the proxy service continues to relay messages between the client and the game service, as indicated at a step 216 . If, however, the client requests a new game instance of the same game type, the proxy service returns to step 206 to obtain the address for the current intake for the selected game type. The process then continues as before.
FIG. 5A illustrates the load-balancing logic that occurs on each node in the cluster. Load balancing is initialized at a step 250 . At a decision step 252 , the load balancer detects any UDP messages from the game services on that node, or from other load balancers on other nodes in the cluster. While there are no incoming UDP messages, the load balancer passes control at a continuation step A to perform the steps illustrated in FIG. 5B (discussed later). When the load balancer detects a new UDP message, the load balancer reads the UDP message at a step 254 .
The load balancer then determines which type of UDP message it has received. In a preferred embodiment, there are four types of UDP messages. One type of UDP message is a “service” message from each game service on the node. Approximately every two seconds, each game service transmits a service message to the load balancer to inform the load balancer of the status of the game service. Preferably, each service message includes a unique name or ID for the game service that is transmitting the service message, the IP address, the TCP port of the game service, the current population of clients being served by the game service, and an indication of whether the game service will accept additional clients. Each game service may accommodate clients for a single game or clients for multiple games. It would not be unusual to handle more than 1,000 clients per game service. The load balancer maintains a table that includes the state information described above for each game service. Thus, if the load balancer determines at a decision step 256 that the incoming UDP message is a service message, the load balancer updates its table of service states at a step 258 . Updating the table includes adding a new game service from the table if a service message is received from a newly started game service.
Another type of UDP message is a “data” message that is received from the other nodes in the cluster. Each data message includes information such as a unique node ID, the node IP address, the total load on a node, a list of all game services running on that node, and an indication of whether the node is accepting new client connections. Preferably, each node sends a data message to the other nodes in the cluster approximately every two seconds in this embodiment. If a data message is not received from a remote node in the cluster within approximately eight seconds, in this example, the remote node is assumed to have failed. In a manner similar to the table of service states, each load balancer maintains a table of node states, including the information described above, for all nodes in the cluster. Thus, if the load balancer for a node determines at a decision step 260 that the UDP message is a data message, the load balancer for the node updates its table of node states at a step 262 . Updating includes adding previously unknown nodes that have recently been activated on the cluster.
Another type of UDP message is an “intake” message, which is received from a remote node in the cluster. An intake message indicates that the remote node in the cluster has decided that the intake for a particular game type should be assigned to a node other than the remote node. The intake message includes identification (e.g., the node IP address and game service TCP port) of the node and of the particular game service that the remote node has determined to designate as the intake for the particular game type. Thus, at a decision step 264 , the load balancer on a node determines whether a UDP message is an intake message, and if so, further determines at a decision step 266 whether the node has been selected to take over the intake for a given game type.
The fourth kind of UDP message in this exemplary preferred embodiment is a “heartbeat” or status message from a node that currently is designated as an intake for any one of the game types. If none of the other three types of UDP messages are detected, the load balancer assumes that the UDP message is a heartbeat or status message at a step 268 . A heartbeat or status message includes information such as the game ID, node IP address, and game service TCP port. Receipt of successive heartbeat or status messages assures all other nodes that the intake for a game type is still functioning. Preferably, a heartbeat or status message is received approximately four times per second for each game type in this embodiment. If a heartbeat message is not received within approximately one second, then one of the prospective receiving nodes assumes that the intake has failed for that game type and assumes control of the intake for that game type. Thus, when a node receives a heartbeat message, the load balancer for that node must determine at a decision step 272 whether the node already has control of the intake for the game type reflected in the heartbeat message. If both the heartbeat message received from another node and the load balancer of the local node indicate that both the other node and the local node control the intake for a particular game type, then the conflict is resolved at a decision step 274 . Resolution of the conflict occurs by providing that the node with the lowest ID number will control the intake for a game type. If there was no conflict, or if the local node relinquishes control of the intake designation after resolution of a conflict, then the load balancer updates a table of intake locations at a step 270 a.
If a local node determines at decision step 266 that a remote node sent an intake message designating a particular game service on the local node as the new intake for a game type, then the local node load balancer determines at a decision step 276 whether the designated game service is still available. If so, the designated game service assumes control as the intake and sends a heartbeat message at a step 278 a . If the designated game service is unavailable, the load balancer selects a new game service to be the new intake for that game type at a step 280 a . If the new intake game service resides on the local node, as determined at a decision step 282 a , then the new intake game service becomes the intake and sends a heartbeat message at step 278 a . If, however, the game service newly selected as the intake resides on a remote node in the cluster, then the load balancer broadcasts an intake message to the other nodes at a step 284 a . The local node then updates its table of intake locations at a step 270 a . Finally, the local node waits for another UDP message at decision step 252 .
Continuation point B indicates the transfer of control from the logical steps illustrated in FIG. 5B to a step 286 , where the load balancing process waits for a loop time-out before going forward to loop again through the steps of FIGS. 5A and 5B . This pause exists to throttle the load-balancer's use of the processor so as not to starve the other services running on the machine. When this time-out finishes, the process proceeds to a decision step 288 , where the load balancer determines whether the load balancer service is to shut down. If so, the load-balancing process ends. If not the load balancer continues to monitor the subnet for incoming UDP messages at a decision step 252 .
FIG. 5B illustrates the steps performed while no UDP messages are incoming. Continuation point A indicates that control is passed from the corresponding point in the logic illustrated in FIG. 5A to a decision step 300 , where the load balancer determines whether it is time to send an updated data message to the rest of the nodes in the cluster. If so, the load balancer first updates its list of local game services at a step 302 by removing any game services from its list that failed to send a service message to the load balancer within the allocated time. For example, if a service message is not received from a particular game service within six seconds, the node assumes the game service has failed, and the failed game service is removed from the load balancer's service list.
The load balancer calculates the load on the node at a step 304 . Preferably, this load calculation is accomplished via a script function that can be dynamically changed while the node is running, to adjust the behavior of the load balancer. In computing a “load value” for the node, the load calculation script uses information such as the node's available memory size, CPU utilization, the total number of clients being serviced on the node, a preset target population of clients, and a preset maximum population of clients. Use of preset, but adjustable parameters enable network administrators to tune each node. Preferably, the load value is also normalized to a range from 0–1000. In this manner, all nodes in the cluster can be compared uniformly even if each node in the cluster has different processing capabilities. The load balancer then assembles a data message and broadcasts the data message to other nodes in the cluster at a step 306 . At a step 308 , the load balancer removes any node information from its table of node information related to any node that failed to send a data message within the allocated time.
The load balancer performs its load-distribution algorithm to determine whether an intake should be moved from the node to another node, and if so, selects the game service on a remote node that should be designated as the new intake for a game type. At a decision step 310 , the load balancer first determines whether to move an intake to another node. To make this determination, the node's load balancer performs another script function. A variety of criteria can be employed in the function used to make the decision. For example, the function may simply be a timer, causing the intake to move at predetermined intervals. Preferably, however, the function uses parameters such as the current client population of the intake game service, the length of time the intake has been situated at that game service, whether the local node has any special affinity for the game type, and the previously computed load value for the node. The function can also use information about the condition of other game instances and other nodes to determine whether the game instance that is currently designated as the intake should give up that designation in favor of another game instance. For example, the function could consider the calculated load on other nodes, or the current client population of other instances of the same game type on other nodes, or on the same node as the current intake. Preferably, however, the function considers only the condition of the current intake, so as not to move the intake around so often that the frequent change of game instances designated as the intake slows the formation and processing of games.
Nevertheless, the script can be modified at any time to provide flexibility to a cluster administrator. Both the logic and threshold values that contribute to the decision can be dynamicly configured independently on each node. For example, a cluster administrator could configure the maximum client population allowed per game service, the maximum time allowed for a game service to be designated as the intake, the maximum load value allowed for a node, and the minimum time allowed between intake moves to control the redesignation of the intake and thus, to balance the processing load as desired.
If the load balancer determines that it is inappropriate to move an intake at the present time, the load balancer moves on to a step 312 to check for time-out of heartbeat messages and service messages. If, however, the load balancer determines that the game instance designated as the intake should now be changed, the load balancer performs a third script function at a step 280 b to calculate a “rating value” for each instance of the game service of the applicable game type on each node in the cluster. This function also uses parameters such as the client population of each game service for the applicable game type and the load value of each node. In addition, the function may also include an affinity parameter that gives higher weight to a node configured so as to be given preference for a particular game type. The game service with the highest rating value in the cluster is then selected to be the new intake for the game type.
If the newly selected intake for a game service resides on the same node as the previous intake for the game service, then at a decision step 282 b the load balancer determines whether the load balancer need only update its own table of intake locations at a step 270 b . However, if the newly selected intake for the game service is at a remote node, the load balancer broadcasts an intake message to all of the nodes in the cluster at a step 284 b . After the intake message is sent, the load balancer then updates its table of intake locations at step 270 b.
The load balancer then checks for time-outs of any heartbeat (status) or service messages at a step 312 . This check is to determine whether any intake game services have failed to issue the expected heartbeat or service message within the allocated time. Determination of whether an intake game service has expired is made at a decision step 314 . If the load balancer has not received an expected heartbeat or service message within the allocated time, then at a decision step 282 c , the load balancer determines whether the expected intake game service resides on the local node. If the expected intake for a game service does reside on the local node, the load balancer assumes that the expected intake game service has failed and selects a new intake game service at a step 280 c , as described above. At a decision step 282 d , the load balancer determines whether the newly selected intake game service also resides on the local node. If so, the load balancer updates its table of intake locations at a step 270 c . If, however, the newly selected intake game service resides on a remote node, then the load balancer broadcasts an intake message to all nodes in the cluster at a step 284 c . The load balancer then updates its list of intake locations at step 270 c.
If decision step 282 c determines that the expected intake for a game service does not reside on the local node, the load balancer assumes that the other node has failed and assumes control of the intake for that game type at a step 316 . As part of this step, the load balancer also selects a game service on the local node to be the intake game service based on the ratings for the local game services. The load balancer then updates its table of intake loactions at step 270 c . As suggested, although the selection and update of a newly selected intake game service is the same as described earlier with regard to the load-distribution algorithm, the selection and update at steps 280 c and 316 are a result of a failure rather than the result of a decision to better distribute the load. Thus, the selection and update at these points are a function of a fault tolerance that is built into the load balancer. This fault tolerance is also reflected in FIG. 5A , beginning at decision step 276 .
Once a new intake game service is selected or if all expected heartbeat and service messages are received in the allocated time, at a decision step 318 , the load balancer determines whether any intake game services reside on the local node. If so, then the load balancer broadcasts a heartbeat at a step 278 b , and proceeds to continuation point B. Similarly, if no intake game services reside on the local node, the load balancer proceeds to continution point B.
Although the present invention has been described in connection with the preferred form of practicing it, those of ordinary skill in the art will understand that many modifications can be made thereto within the scope of the claims that follow. Accordingly, it is not intended that the scope of the invention in any way be limited by the above description, but instead be determined entirely by reference to the claims that follow. | A method and system for distributing work load in a cluster of at least two service resources. Depending upon the configuration, a service resource may be an individual process, such as a single instance of a computer game, or a node on which multiple processes are executing, such as a Server. Initial connection requests from new clients are directed to a single entry-point service resource in the cluster, called an intake. A separate intake is designated for each type of service provided by the cluster. The clients are processed in a group at the service resource currently designated as the intake to which clients initially connected, for the duration of the session. Based upon its loading, the current intake service resource determines that another service resource in the cluster should become a new intake for subsequent connection requests received from new clients. Selection of another service resource to become the new intake is based on the current work load of each resource in the cluster. All resources in the cluster are periodically informed of the resource for each service being provided that was last designated as the intake, and of the current load on each resource in the cluster. Subsequently, new clients requesting a service are directed to the newly designated intake for that service and processed on that resource for the duration of the session by those clients. | 7 |
FIELD OF THE INVENTION
Embodiments of the present invention relate to amplifiers that retain the power amplifier spectral characteristics over a wide range of output power.
BACKGROUND OF THE INVENTION
An electronic amplifier (amplifier, amp) is an apparatus that enables an input electrical signal to control power from a source independent of the signal and thus is capable of delivering an output that bears some relationship to, and is generally greater than, the input signal. An amplifier may be designed for a specific purpose. For example, radio frequency (RF) amplifiers may convert low-power signals with frequencies generally in the portion of the electromagnetic spectrum between audio and infrared into a larger signal with more power, typically for driving the antenna of a transmitter. In another example, an audio amplifier may amplify audio signals (e.g., signals in the range of human hearing) to a suitable level (magnitude) for driving loudspeakers or other devices. A guitar amplifier is another example of an amplifier designed for a specific purpose. A guitar amplifier is designed to amplify the electrical signal of guitar or an acoustic pickup.
An amplifier may strive to reproduce the electromagnetic spectrum (e.g., spectral characteristics, frequencies, tone) of the input signal. Alternatively, the amplifier may alter the spectrum of the input signal. The output spectrum may depend on the output power level (magnitude). For example, a guitar amplifier may add effects such as distortion at high output power levels. A musician may find these effects desirable. However, guitar amplifiers may fail to reproduce the same effects at lower output power. For example, a musician using a guitar amplifier in a concert hall or arena setting with a high power output may desire to have the same effects at a lower output power while playing in a smaller room or location. Maintaining the relationship of input to output spectrum over the dynamic range (the ratio between the largest and smallest possible values) of output power may not be achievable with typical amplifiers.
In other examples, it may be desirable for audio amplifiers to faithfully reproduce the electromagnetic spectrum of the input signal at the output regardless of output power levels. Audio amplifiers that introduce distortion or other effects alter the original spectrum (e.g., sounds) which listeners may find objectionable. In this example, it is desirable to maintain the relationship of input spectrum to output spectrum over the dynamic range of output power without distortion.
Electronic amplifiers that maintain a desired relationship of input spectrum to output spectrum over the dynamic range of output powers alleviate the problem of power output dependent spectral variations. Thus, maintaining a spectral relationship between an input and output signal in an amplifier is a need felt by many users across multiple fields.
BRIEF DESCRIPTION OF THE DRAWING
Embodiments of the present invention will be described with reference to the drawings, wherein like designations denote like elements, and:
FIG. 1 is a functional block diagram of an apparatus to amplify electrical signals in accordance with various aspects of the present invention;
FIG. 2 is a functional block diagram of the amplifier of FIG. 1 for audio signals in accordance with various aspects of the present invention;
FIG. 3 is a schematic diagram of a circuit of a fixed bias power amplifier of the audio amplifier of FIG. 1 ;
FIG. 4 is a schematic diagram of a circuit showing a voltage regulator biasing of the amplifier of FIG. 2 ;
FIG. 5 is a schematic diagram of a circuit of an implementation of the voltage regular bias of FIG. 4 according to various aspects of the present invention;
FIG. 6 is a schematic diagram of the circuit of FIG. 4 showing a tracking control grid bias;
FIG. 7 is a schematic diagram of a circuit showing an implementation of a tracking control grid bias of FIG. 6 according to various aspects of the present invention;
FIG. 8 is a schematic diagram of a circuit of FIG. 6 showing a phase splitter bias;
FIG. 9 is a schematic diagram of a circuit of FIG. 8 showing a control grid phase splitter bias according to various aspects of the present invention; and
FIG. 10 is a schematic diagram of FIG. 8 showing a phase splitter with a voltage controlled differential amplifier according to various aspects of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
A signal is used to convey information. An electrical signal may be characterized by voltage (e.g., electromotive force), current (e.g., flow of electric charge), electromagnetic waves (e.g., spectrum, frequencies, wavelengths, tones), power (e.g., rate of transferring or transforming energy), and/or other quantities. As used herein, the term “signal” means an electrical signal that conveys information.
An amplifier boosts (e.g., enlarges, magnifies, increases, raises, gains) one or more characteristics (e.g., voltage, current, power) of one or more signals. Amplifiers may have unity gain (e.g., no amplification). Amplifiers may also attenuate a signal. Amplifiers may be designed for particular applications (e.g., guitar amplifier), frequencies ranges (e.g., audio amplifier, radio frequency amplifier), and/or to boost particular characteristics (e.g., current amplifier, voltage amplifier, differential amplifier, inverting amplifier, integrating amplifier). As used herein, the term “amplifier” or “amp” means any electrical or electronic equipment that amplifies one or more characteristics of a signal.
An amplifier may include a preamplifier (pre-amp or preamp), a phase splitter, a power amplifier, and a power supply ( FIG. 1 ). An amplifier may also include a tone stack and a transformer ( FIG. 2 ). A pre-amp may electrically couple (e.g., establish an electrical connection, establish a path for current to flow) to a low-level input signal (source). The components of an amplifier may be contained in a single enclosure (e.g., housing, box, assembly, case). The components may be contained in multiple enclosures with any combination of components in each enclosure.
A pre-amp may present a suitable impedance (e.g., matched impedance) to a signal source. A pre-amp may provide gain (e.g., amplification) to the input signal to produce a signal suitable for further processing. A user interface may be provided to a user to adjust the gain of the pre-amp. A pre-amp may provide suitable output impedance to a component for further processing. A pre-amp may provide equalization and/or mixing of the input signal. A pre-amp may produce distortion in a signal. A pre-amp may contain any combination of conventional circuit elements (e.g., electron tubes, semiconductors, integrated circuits, transistors, resistors, capacitors, inductors, transformers) to perform these functions. A pre-amp may be omitted (e.g., left out, not included) from an amplifier if its function is performed by another component or if its function is not required.
A phase splitter may electrically couple to a pre-amp to provide further processing. A phase splitter may produce one or more signals from an input signal which differ in phase (e.g., different polarities, quadrature signals) from one another. A phase splitter may provide a suitable impedance for an input and/or an output circuit coupled to the phase splitter. For example, a phase splitter may separate an input signal into two signals with opposite polarities for further processing by a push-pull amplifier circuit. In another example, a phase splitter may produce a single signal for further processing by single phase amplifier. A phase splitter may be omitted from an amplifier if only a single phase of the signal is required for further processing. A phase splitter may contain any combination of conventional circuit elements to perform these functions.
A power amplifier amplifies an input signal to a sufficient power level (magnitude) to drive a load (e.g., utilization device, antenna, loudspeaker, circuit that consumes electric power). A load may be one or more devices. A device that provides additional processing may be a load. A power amplifier may be the last stage in an amplifier before a load. A user interface may be provided to a user to adjust an amount of power output by the power amplifier. A power amplifier may employ any class of operation or service (e.g., Class A, Class AB, Class C, Class D). The signal output by the power amplifier may include distortion (e.g., harmonic distortion, crossover distortion). The output of the power amplifier may be proportional to the input signal (e.g., linear). There may be a non-linear relationship between the output of the power amplifier and the signal input to the power amplifier. A power amplifier may contain any combination of conventional circuit elements to perform these functions.
A power supply includes a supply of energy. Energy may be used for enabling the operation of electronic circuits (e.g., devices) such as an amplifier, processing circuit, and/or a user interface. A power supply may include any conventional component for providing energy such as a battery, a transformer that transforms line power, and/or a capacitor. A power supply may store energy for providing energy. Energy from a power supply may be used as a force (e.g., voltage, current) for an amplifier as discussed herein.
Tone refers to the pitch, quality, and strength of musical or vocal sounds. A tone stack may output a processed input signal that has been modified in accordance with a user interface. A tone stack may provide a user interface to adjust a frequency response (e.g., the quantitative measure of the output spectrum) of an input signal. A tone stack may adjust timbre (e.g., tone color, tone quality) of an audio signal. The user interface may provide for user adjustment of treble (e.g., tones at the higher range of human hearing), bass (e.g., tones at the lower frequency or range of human hearing), and/or middle (e.g., tones at the midrange of human hearing). A tone stack may allow a user to control equalization, reverberation, and/or mixing of the input signal. A tone stack may provide an effects output port (e.g., connection, socket, plug) and an effects input port for an external device to connect. The external device may provide modification (e.g., additional effects) to the signal from the effects output port and return the modified signal to the effects input port of the tone stack. A tone stack may contain any combination of conventional circuit elements to perform these functions.
A transformer may provide impedance matching of an amplifier output to an impedance of a load. A transformer may provide galvanic isolation (e.g., blocking of direct current). A transformer may provide alternating current restoration (e.g., converting direct current in a transformer primary winding to alternating current in the transformer secondary winding). Impedance matching may maximize the power transfer from an amplifier to a load. Impedance matching may minimize a signal reflection from a load. A transformer may provide a center tap for connecting to a bias voltage. A transformer may provide connections to winding ends to accept output signals from a power amplifier. A transformer may contain any combination of conventional circuit elements to perform these function.
A user interface may include electronic devices (e.g., switches, push buttons, touch screen, potentiometers, rheostats, wireless transceiver, remote controls) for receiving information (e.g., data) from a user. A user may manually manipulate one or more electronic devices of a user interface to provide information. Electronic devices for receiving information from a user may include a wireless receiver that receives information from an electronic device (e.g., smartphone, tablet, watch). A user may manually provide information to a user interface via an electronic device. A user interface may include electronic devices for providing information to a user. A user may receive visual and/or auditory information from a user interface. A user may receive visual information via devices (e.g., LCDs, LEDs, light sources, graphical and/or textual display) that display information. A user interface may include a wireless transmitter for transmitting information to an electronic device for presentation to a user.
For example, amplifier 100 , shown in FIG. 1 , includes pre-amp 120 , phase splitter 140 , power amplifier 150 , and power supply 160 . Pre-amp 120 electrically couples to an input signal and provides the functions of a pre-amp as described above. Pre-amp 120 processes the input signal for further processing by phase splitter 140 . The input of phase splitter 140 electrically couples to the output of pre-amp 120 . Phase splitter 140 provides the functions of a phase splitter as described above. The output of phase splitter 140 electrically couples to the input of power amplifier 150 . Power amplifier 150 provides the functions of a power amplifier as described above. Power amplifier 150 electrically couples to a load. Power supply 160 provides the energy required by pre-amp 120 , phase splitter 140 , and power amplifier 150 . A user interface (not shown) may provide the user a means for controlling the amount of power output from amplifier 100 . A user interface may provide the user with a means of controlling other characteristics and/or functions of amplifier 100 .
In another example, amplifier 200 , shown in FIG. 2 , includes input port 210 , pre-amp 220 , tone stack 230 , phase splitter 240 , power amplifier 250 , transformer 260 , loudspeaker 270 , and power supply 280 . Input port 210 may provide an electrical connection for an input signal and couples that signal to an input of pre-amp 220 . A gain (e.g., amplification, boost, volume, increase in power) of pre-amp 220 may be set via a user interface. Pre-amp 220 performs the functions of a pre-amp on the input signal as described above. Tone stack 230 couples to pre-amp 220 and takes as an input the signal output by pre-amp 220 . A user may adjust (e.g., modify, alter) the tonal qualities (e.g., timbre, bass, treble, midrange, reverberation) of the signal processed by tone stack 230 via a user interface. Tone stack 230 performs the function of a tone stack as described above and outputs a signal for phase splitter 240 . Phase splitter 240 couples to tone stack 230 and performs the function of a phase splitter as described above. Phase splitter 240 may separate a signal into one or more phases to be processed by power amplifier 250 .
Power amplifier 250 couples to phase splitter 240 and receives the signal output by phase splitter 240 . The output power of the signal from power amplifier 250 may be controlled through a user interface. Power amplifier 250 may provide distortion (e.g., harmonics, crossover) to the signal. Power amplifier 250 performs the function of a power amplifier as described above.
Power amplifier 250 may be a push pull amplifier which has an output stage that can drive a current in either direction through a load. The output stage of a typical push pull amplifier may include at least one electron tube (e.g., vacuum tube, receiving tube, gas tube). Electron tubes for amplifiers may be conventional amplifier tubes (e.g., triode, tetrodes, pentodes). The output stage may include at least one semiconductor device (e.g., transistor, BJT, FET). Bipolar junction transistors (BJTs or bipolar transistors) are devices that rely on the contact of types of semiconductor (e.g., PNP, NPN) for its operation. Field-effect transistors (FETs) use an electric field to control the shape and therefore the conductivity of a channel of one type of charge carrier in a semiconductor. FETs may be junction field-effect transistors (JFETs), metal oxide semiconductors (MOSFETs) or any other conventional FET transistor.
A push pull amplifier may operate in a particular class of service (e.g., Class A, Class B, Class AB) with any of the devices described above (e.g., electron tube, BJT, FET). The class of service may be changed by altering the bias parameters of a device.
Transformer 260 couples to, and receives a signal from, power amplifier 250 . Transformer 260 provides a matching impedance to loudspeaker 270 . Transformer 260 provides the function of a transformer as described above. Transformer 260 may provide galvanic isolation. Transformer 260 may provide alternating current restoration.
Power supply 280 provides a source of energy for pre-amp 220 , tone stack 230 , phase splitter 240 , power amplifier 250 , and transformer 260 . Power supply 280 performs the function of a power supply as described above.
The components of amplifier 200 may be contained within a single housing (e.g., enclosure, cabinet). A plurality of housings may contain any combination of components, each housing electrically coupled to another housing to provide the electrical connections between components described above.
Power amplifier 302 in FIG. 3 provides an example of a push pull amplifier performing the functions of power amplifier 250 . The output stage in this example uses two pentode electron tubes, tubes 310 and 314 . The suppressor grids of tubes 310 and 314 are connected to their respective cathodes which are in turn connected to the circuit ground. The suppressor grids may be connected to a biasing circuit with any combination of resistors, capacitors, diodes, or other conventional circuit elements. The heater connections to a power supply are not shown. VB+ provides a fixed voltage through a center tap of transformer 360 to the plates of tubes 310 and 314 . VB+ also provides a fixed voltage, filtered through RFLTR and CFLTR, with current limited by RSG 1 and RSG 2 , to the screen grids of tubes 310 and 314 , respectively. Phase splitter 340 provides two signals to the input of power amplifier 302 . The input signals are filtered by CDRV 1 and RDRV 1 , which also provides AC (alternating current) coupling (e.g., capacitive coupling, blocking of direct current signals), to tube 310 and biased by fixed voltage Vbias through RCG 1 and RDRV 1 . Similarly, CDRV 2 and RDRV 2 provides filtering and AC coupling, and RCG 2 and RDRV 2 with Vbias provides biasing for tube 314 . The biasing in this example is set (e.g., predetermined, established) by a circuit designer.
For push pull Class AB 1 operation, the plate voltage, screen voltage and total zero signal plate current must be maintained in accordance with tube 310 and 314 specifications. As an example, with a 6BQ5 (EL84) power amplifier pentode for tubes 310 and 314 , plate and screen grid voltages are 300 volts and total zero signal plate (quiescent) current is 36 mA (milliamperes) per tube according to the manufacturer's specifications (e.g. data sheet, application note). The voltages and current may be different for other tube selections. As the power output or amplifier gains changes, tubes 310 and 314 may not remain within the design specifications for push pull Class AB1 operation.
In an embodiment of the present invention, power amplifier 402 in FIG. 4 shows the use of a voltage regulator to supply a regulated voltage to the screen grids of tubes 310 and 314 . Regulator 420 may supply a predetermined voltage. Rcontrol may adjust the output voltage of regulator 420 which, in turn, controls the output power. Regulator 420 may automatically maintain a voltage level (typically within a ±5% output voltage tolerance) and thus may reduce unwanted voltage variations (e.g., ripple, spiking). Voltage regulator 420 may be implemented with a non-linear regulator. A linear regulator may be used to implement the functions of regulator 420 . Any combination of conventional circuit components may be used to perform the functions of voltage regulator 420 .
In other embodiments of the present invention, the voltage regulator may supply a regulated voltage to the plates of tubes 310 and 314 . The voltage regulator may supply a regulated voltage to the screen grids and plates of tubes 310 and 314 .
Regulator 500 in FIG. 5 provides an example circuit of voltage regulator 420 . A convention linear voltage regulator (e.g., Microchip LR8 high input voltage, adjustable 3-terminal linear regulator) may be used for regulator U 51 . Unregulated input power is supplied to the IN connection. The regulated output voltage is provided at the OUT connection. The ratio of R 52 and R 53 determines the output voltage level. The output voltage may be controlled via a variable resistance between the CONTROL connection and circuit ground. Thus, the CONTROL input determines the output power of the power amplifier. Bypass transistor Q 41 boosts the current available through regulator 500 .
In another embodiment of the present invention, power amplifier 602 in FIG. 6 includes control grid (CG) bias 630 . CG bias 630 may follow a control law in which the output voltage is determined by the voltage at the input at any given instant. The control law relationship may be linear or may be non-linear. CG bias 630 maintains a relationship between a screen grid voltage and a control grid voltage on tubes 310 and 314 while a constant plate voltage may be maintained. The tonal characteristics of an output audio signal are thus substantially invariant (e.g., relatively constant, little or no change) when the screen grid voltage changes because the bias voltage changes in a control law relationship to the screen grid voltage. By controlling the CG bias voltage, the zero-signal (quiescent) plate current can be maintained according to the tube specifications.
As used herein, “substantially invariant” and “relatively invariant” when used with tonal characteristics or input-output spectral relationships means that any change in the frequency composition of the output signal is imperceptible (e.g., unnoticeable, undetectable, indistinguishable, indiscernible) to an ordinary person listening to the sounds produced through a loudspeaker or that any change in frequency composition does not alter a result of any further processing of the output signal.
CG bias 700 in FIG. 7 is an example of a circuit to perform the function of CG bias 630 . Operational amplifier (OPAMP) U 701 provides an inverted (e.g., opposite polarity) signal proportional to fixed reference voltage V 715 . The ratio of impedances R 702 to R 707 determines the gain of OPAMP U 701 . OPAMP U 702 produces a signal proportional to the difference of an IN signal and the output from OPAMP U 701 . In general, the output of OPAMP U 702 may be the product of the impedance value of R 704 with the sum of IN divided by the value of impedance R 709 and the output voltage of OPAMP U 701 divided by the impedance of R 710 . The resulting output of OPAMP U 702 follows a control law relationship to the IN input signal (the screen grid voltage). The functions of an operation amplifier may be implemented with any combination of conventional electronic components.
If U 310 and U 314 are both 6BQ5 (EL84) electron tubes, for example, and the screen grid voltage changes from 300 volts to 100 volts while the plate voltage is maintained at 300 volts, the control grid voltage must decrease by 773 millivolts to maintain a zero signal (quiescent) plate current of 36 mA, as specified by the manufacturers for the particular class of service. Thus, if a linear relationship is assumed, CG bias 700 produces the following relationship:
V CGB =−0.053135V SGB +4.54 Volts Equation 1:
where V CGB is the control grid bias voltage (output) and V SGB is the screen grid bias voltage (input).
The values of fixed reference voltage V 715 and impedances R 702 , R 704 , R 707 , R 709 and R 710 may be appropriately selected to achieve the relationship in Equation 1 in this example. Capacitors C 702 and C 704 may be included to provide low-pass filtering or may be omitted from CG bias 700 .
In another embodiment of the present invention, circuit 800 in FIG. 8 includes a voltage controlled differential amplifier (VCDA) in phase splitter 840 . The VCDA is controlled by control law amplifier 850 . The combination of amplifier 850 and VCDA may prevent the loss of dynamic range of output power due to the control grid voltage of tube 310 and/or tube 314 becoming positive with respect to the cathode. A change in the power amplifier class of service from Class AB1 to Class AB2 would result in an electron tube grid voltage becoming positive with respect to the cathode. Amplifier 850 produces a signal in relation to the control grid bias voltage of tubes 310 and 314 that, in turn, changes the drive level within phase splitter 840 .
An example of a circuit implementing a control law amplifier is shown in amplifier 900 in FIG. 9 . OPAMP U 901 produces a voltage proportional to fixed reference voltage V 915 . The voltage is proportional to the ratio of the values of impedances R 902 to R 907 . OPAMP U 902 produces a voltage proportional to the difference in voltage between an IN input signal and an output of OPAMP U 901 . The values of impedances R 902 , R 904 , R 907 , R 909 , and R 910 determine the relationship of the voltage at output OUT to reference voltage V 915 and the IN input voltage. The functions of OPAMPs U 901 and U 902 may be implemented with any combination of conventional electronic circuit components. OPAMPS U 901 and U 902 may be implemented with integrated circuit operational amplifiers (e.g., Texas Instruments (TI) TL082, TI TL072, TI LF353).
An example of a circuit implementing a phase splitter with a VCDA is shown in phase splitter 1000 in FIG. 10 . Transistors Q 1001 and Q 1002 form a differential amplifier controlled by input VGB. Input voltage VGB determines the current through Q 1002 and thus the cathode current in tubes U 1001 and U 1002 . In this example, tubes U 1001 and U 1002 are triode electron tubes arranged in a common cathode configuration (e.g., long-tailed pair, differential pair). Phase splitter 1000 produces two output signals, DRIVE-A and DRIVE-B, with opposite polarities (e.g., 180 degree phase difference) which may serve as inputs to power amplifiers 302 , 402 , 602 , and 802 .
The differential amplifier in phase splitter 1000 may be implemented with transistors as shown. The differential amplifier may be implemented with operational amplifiers. Any combination of conventional electronic components that performs the function of a VCDA may be used.
The functions of tubes U 1001 and U 1002 may be implemented with electron tubes. Transistors may be used to implement the functions of U 1001 and U 1002 . Operational amplifiers may be used to implement the functions of U 1001 and U 1002 . Any combination of conventional electronic components that perform the functions of U 1001 and U 1002 may be used.
Implementations of the present invention in an amplifier may include fixed or variable voltage regulator 420 of FIG. 4 . Other implementations of the present invention may include control law amplifier 850 and a VCDA of phase splitter 840 . In still other implementations, an amplifier may include fixed or variable voltage regulator 420 , control law amplifier 630 , control law amplifier 850 , and a VCDA of phase splitter 840 of FIGS. 4-10 .
The foregoing description discusses preferred embodiments of the present invention, which may be changed or modified without departing from the scope of the present invention as defined in the claims. Examples listed in parentheses may be used in the alternative or in any practical combination. As used in the specification and claims, the words ‘comprising’, ‘including’, and ‘having’ introduce an open ended statement of component structures and/or functions. In the specification and claims, the words ‘a’ and ‘an’ are used as indefinite articles meaning ‘one or more’. When a descriptive phrase includes a series of nouns and/or adjectives, each successive word is intended to modify the entire combination of words preceding it. For example, a black dog house is intended to mean a house for a black dog. While for the sake of clarity of description, several specific embodiments of the invention have been described, the scope of the invention is intended to be measured by the claims as set forth below. In the claims, the term “provided” is used to definitively identify an object that not a claimed element of the invention but an object that performs the function of a workpiece that cooperates with the claimed invention. For example, in the claim “an apparatus for aiming a provided barrel, the apparatus comprising: a housing, the barrel positioned in the housing”, the barrel is not a claimed element of the apparatus, but an object that cooperates with the “housing” of the “apparatus” by being positioned in the “housing”. | An electronic amplifier delivers to a load an output signal related to an input, typically with increased power. As the power output, volume, or gain of the amplifier is changed, so may the spectral characteristics of the signal. In order to maintain the desired spectral or tonal character of the output signal over the dynamic range of output power, biasing of the amplifier must be adjusted. Particular ratios of drive and bias currents and/or voltages for different implementations of amplifier technologies should be relatively constant to produce substantially invariant input-output spectral relationships from low power output through high power output settings. Several techniques are presented which provide these relationship in amplifiers. | 7 |
BACKGROUND OF THE INVENTION
This invention relates to the process now known as TCET (transcranial electrotherapy), that is to say the application of a series of electric signals of defined amplitude and duration across the head of a patient or a test animal by means of percutaneous electrodes generally attached to the external part of the ear.
TCET is described in detail in U.S. Pat. No. 4 646 744 issued Mar. 3, 1987. The U.S. patent describes the general concept of TCET and distinguishes it from other known methods, in particular TENS (Trans cutaneous Electrical Nerve Stimulation), electro-acupunture and invasive electrical treatment. TCET is particularly important in the control of chronic refractory pain, but is also important in treatment of addictive states.
We have now found that for TCET to be successful a number of factors must be considered and the application of the electrical signals must be carried out in a precisely defined manner using signals having particular parameters. It is thus the object of the present invention to provide a method of applying TCET which is effective and reproducible.
U.S. Pat. No. 4 646 744 discloses the application of a signal comprising trains of pulses separated from other trains by off periods. Each of these trains comprises a packet of a certain number of individual pulses spaced temporally from other packets by off periods. The pulses are generally either DC or substantially symmetrical AC wave forms applied at a number of different frequencies, typically 10 Hz, 100 Hz, 25-30 Hz, 500 Hz, and 200 Hz. The pulse width, that is to say the duration of a positive pulse from a zero value to a zero value, is typically 0.1 to 0.5 msec, although pulse widths of 1.5 msec are also mentioned. As described, the signals have a current of several mA, and an amperage of less than 100 mA being sufficient.
As stated, the pulses are given in packets of consecutive pulses described as "trains" separated by off periods which can regularly spaced or which can be irregular and typically increasing in duration, e.g. in an arithmetical progression. The typical overall duration of these series of trains is several days.
SUMMARY OF THE INVENTION
We have now established that there are a number of important parameters to supply if the treatment is to be effective and reproducible. In the first place it is important to consider the impedance of the circuit, as controlled by the electrode attachment to the ear. We have now found that conventional patch electrodes, even if relatively small for accurate placement, as advised in the above-mentioned U.S. patent, provide a relatively high impedance, typically 300-600 kΩ, even when used with electrode gel, and also a relatively large capacitance. Similarly, a blunt gold electrode has an impedance of 300-500 kΩ. I have found that the electrode should be in the form of a generally conical needle point capable of penetrating the epidermis, so as to provide good electrical contact over a very small surface area. A steel needle electrode of this type provides an impedance of about 65-90 kΩ, whale a carbon needle provides an impedance of about 25-35 kΩ. The point contact also provides a low capacitance.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side view of an electrode assembly;
FIGS. 2 and 3 are plan and side views of the assembly before being folded;
FIG. 4 is a large side view of the electrode carrier of the assembly;
FIGS. 5A and 5B, 6 and 7 show a power supply circuit and signal generator.
DESCRIPTION OF THE INVENTION
The signal can be provided to the electrode with a very low current. It is highly desirable to use an operating current of only a few microamps, typically 10-15 μA e.g. about 10-12 μA. Thus, the operating current should be a factor of 10 -4 times the operating current suggested in the above-mentioned U.S. patent.
The low current signal can be provided by the simple procedure of using a signal generator working at a much higher current and then including in the circuit a defined high impedance to reduce the current to the required microamp levels. Typically a signal is generated at from 2-4 volts and passed through a 180 kΩ resistance.
It is also most important that the connecting leads are kept as short as possible, or are screened (if this is feasible). Long unscreened leads (or, even worse, long screened but non-earthed leads) are found to act as aerials and pick up a large amount of ambient electromagnetic radiation, thus delivering to the patient a large amount of "noise" along with the signal. This is at best unhelpful, and at worst positively harmful, apparently causing aggressive tendencies in rats and irritation or anxiety in humans.
Another particularly preferred aspect of the invention, comprises an electrode in the form of an ear clip, generally comprising a bifurcated or generally U-shaped holder capable of being located around the ear lobe and supplied with a conically pointed electrode needle arranged to press against the ear lobe located between arms of the U-shaped clip, the electrode being provided with adjustable means for controlling the pressure at which the point of the electrode presses into the outer layers of the skin; the electrode also being provided with an electrical connection to the signal generator. The clip is conveniently made of molded plastic material, for example nylon or polyalkylene. The adjustable means for controlling the pressure is conveniently a transversely mounted screw device controlled by, for example, a knurled knob and the electrode is conveniently attached to the lead by a conventional crimped ferrule.
A further important operating condition is that the overall net charge delivered to the patient should effectively total zero (i.e. the positive charge should balance the negative charge in an alternating current), but that the operating signal should effectively consist of pulses of positive current. This result can be achieved by using an AC waveform in which the positive pulse is relatively short and high, while the following negative pulse is relatively long and low, the "areas" of the pulses being equal. (This description refers to the conventional representation of pulses as voltage plotted against time). Typically, the positive pulse should have a duration of about 2-2.2 msec (although pulse width of 0.22 msec and 7 msec are also effective in some cases) and the negative pulse width should be 5-10 times as long e.g. about 7 times. The pulse width (pulse duration) must obviously be less than the reciprocal of the frequency and we find that for frequencies up to, say, 150 Hz a pulse width of 2.0 msec is optimal, while at a frequency of about 500 Hz a pulse width of I msec is optimal and at a frequency of about 2000 Hz a pulse width of less than 0.1 msec is optimal. If it is desired to use ultra high frequency (MHz) signals, the pulse width is undefined. It is also important that the positive pulse is not significantly "spiked" at its onset, contrary to the teaching of U.S. Pat. No. 4,646,744.
As a further preferred feature of this invention it is generally undesirable for the sequence of packets of pulses (previously referred to as "trains") to be continued for days without longer breaks. We have now found that the signal should be supplied as packets of pulses separated by short pauses in a relatively short sequence which can, more realistically, be referred to as a "train". The trains themselves are then separated by longer breaks.
At the particularly preferred frequency of 10 Hz, we have found that a typical train should contain packets of 750 or 1000 individual pulses, i.e. packets of 75 or 100 seconds in duration, separated by pauses of about 10 seconds, for a total train duration of 1800-3600 seconds, e.g. 2400 seconds. The rest period between successive trains of this type should preferably be a minimum of 3 hours. We have found that this type of signal provides distinctly better results than either continuous operation or operation involving a series of packets and gaps continued for several days.
In a further preferred aspect, the invention includes apparatus for generating the appropriate signal, as described above.
Such apparatus may conveniently comprise any suitable electronic circuitry capable of providing an appropriate electrical signal e.g. that described in the abovementioned U.S. patent. In a preferred embodiment, it comprises digital analog circuitry to gate the signals into the required conformation.
Subjects receiving specific prescriptions, including the 250 and 750 ppp delivered at 10 Hz find that their mouths become dry during treatment sessions of one hour duration. Furthermore, alcoholics receiving treatment To ameliorate the abstinence symptoms associated with the withdrawal of alcohol become dry mouthed and also exhibit pronounced hypoglycaemic responses. However, it is undesirable to let the patient drink during the treatment period, as tests are carried out on the saliva, which would be diluted by the water etc. It is now therefore recommended that the recipients of the treatment suck commercially available glucose tablets (generally containing approx. 3 g of the monosaccharide) as a salivation stimulant. One tablet is administered 15-20 min before commencement of therapy and thereafter at 30 min intervals upon the discretion of the supervising clinician.
In summary, therefore, we now provide a modified version of the method described in the U.S. Patent, utilizing a combination of parameters selected from those described above, which enable for the first time the method to be applied in a scientifically reproducible, effective manner, especially for pain control. A convenient electrode clip for attachment to the ear is also provided. There is also provided signal generating apparatus for providing the type of signal train described.
The following description is by way of exemplification of various aspects of the invention.
The relevance of a number of different treatment parameters was evaluated in rats using a signal of 10 Hz at 2-4 volts. Analgesic effect was measured by measuring the tail flick latency (TFL) in rats using a conductive heat challenge in the standard way. Further indication of activity is provided by measurement of β-endorphin (BE) levels, adrenocorticotrophic hormone (ACTH) levels and also the levels of corticosterone and cortisol. The estimation of these levels is carried out by measuring their immunoreactivity (-Ir) using an immunological technique using radio labelled antigen (referred to as It). The details of the electrical stimulation (ES) are as stated in the footnotes to each table.
TABLE 1______________________________________TFL in rats receiving continuous mode ES of variouscurrent amplitudes.CurrentAmplitude TFL(μA) (s)______________________________________420 13.4 ± 6.5*330 17.0 ± 4.2*250 20.0 ± 6.2180 27.3 ± 2.6*80 27.0 ± 3.2*20 26.0 ± 3.4*15 35.2 ± 7.2*10 32.2 ± 8.1* 5 32.0 ± 6.6* 1 28.1 ± 5.0* 0.5 24.6 ± 10.0 0.2 21.4 ± 8.8 0.1 22.4 ± 6.5 0.05 21.4 ± 10.1Sham-treated 21.3 ± 5.0______________________________________
Results are the mean ±SD of 6 rats in each group. Continuous mode ES administered at 10 Hz frequency 2.0 Oms pulse width for a period of 1800 s. Noxious challenge: TFL determined with conductive heat challenge at 60° C. applied to the ventral surface.
* Significantly different (P<0.05) from sham-treated value by unpaired Student's t test.
TABLE 2______________________________________Effect of varying the pause duration Dp (time off) andstimulation period (time on) on the antinociceptiveaction of interrupted mode ES in the TFL.______________________________________Dp (s) TFL (s)______________________________________100 18.4 ± 7.8*50 18.2 ± 8.6*20 15.2 ± 6.010 28.1 ± 7.0* 5 20.5 ± 11.8* 2 17.7 ± 7.3______________________________________Time on (s) TFL (s)______________________________________ 5 9.1 ± 3.4*25 28.1 ± 7.0*50 30.6 ± 6.2*75 33.8 ± 7.4*100 35.4 ± 6.1*150 24.0 ± 5.0*200 23.8 ± 4.2*250 22.1 ± 5.4*Sham- 14.4 ± 6.4Treated______________________________________
Results are the mean ±SD of 18 rats in each group.
For determination of optimum pause: ES consisted of 25 s periods of stimulation separated by the pause periods indicated and administered for a total treatment time of 1800 s. Sham-treated animals were restrained for the corresponding period of time with electrodes inserted but no current was passed.
Noxious challenge: TFL determined with conductive heat challenge at 60° C. applied to the ventral surface.
* Significantly different (P<0.05) from sham-treated value by unpaired Student's t test.
TABLE 3______________________________________Effect of varying the signal pulse width on theantinociceptive action of interrupted mode ES in the TFL.Pulse width (ms) TFL (s)______________________________________1.8 19.1 ± 2.1*1.9 16.9 ± 7.8*2.0 28.4 ± 5.5*2.1 31.4 ± 8.2*2.2 29.0 ± 6.1*2.4 19.0 ± 7.1*2.6 17.4 ± 9.1Sham-treated 14.2 ± 6.5______________________________________
Results are the mean ±SD of 12 rats in each group.
ES consisted of periods of 100 s stimulation separated by 10s pause periods administered for a total treatment time of 1800 s. Sham-treated animals were restrained for the corresponding period of time with electrodes inserted but no current was passed.
Noxious challenge: TFL determined with conductive heat challenge at 60° C. applied to the ventral surface.
* Significantly different (P<0.05) from sham-treated value by unpaired Student's t test.
TABLE 4______________________________________Effect of varying the current amplitude on theantinociceptive action of interrupted mode ES in the TFL.Current TFLAmplitude (μA) (s)______________________________________33.0 15.6 ± 7.520.0 23.4 ± 9.9*18.0 19.7 ± 7.6*12.5 31.8 ± 7.0*11.0 32.2 ± 5.2*10.0 26.4 ± 7.0* 9.5 14.6 ± 3.7 5.0 13.4 ± 3.1Sham-treated 14.2 ± 6.5______________________________________
Results are the mean ±SD of 12 rats in each treatment group.
Interrupted mode ES of 2.0 ms pulse width signals at the current amplitude indicated, consisted of periods of 100s stimulation separated by 10s pause periods administered for a total treatment time of 1800 s. Sham-treated animals were restrained for the corresponding period of time with electrodes inserted but no current was passed.
Noxious challenge: TFL determined with conductive heat challenge at 60° C. applied to the ventral surface.
* Significantly different (P<0.05) from sham-treated value by unpaired Student's t test.
TABLE 5______________________________________Comparison of the antinociceptive effects ofinterrupted, continuous mode ES and sham treatment.Treatment Group TFL______________________________________Interrupted 30.8 ± 7.4* (18)Continuous 18.3 ± 11.5* (18)Sham-treatment 14.3 ± 6.4 (19)Basal 10.8 ± 5.3* (16)______________________________________
Results (in s) are the mean ±SD for numbers of rats in parentheses.
Rats received a 1800 s treatment period of one of either: Interrupted mode ES of 100s of stimulation separated by 10 s pause periods when the current was off; continuous mode ES identical in all respects to interrupted except devoid of pauses; Sham-treatment (electrodes inserted but no current passed); Basal rats restrained briefly (<300s) for noxious challenge in TFL.
Noxious challenges: TFL determined with conductive heat challenge at 60° C. applied at the ventral surface.
* Significantly different (P<0.05) from sham-treated value by unpaired Student's t test.
TABLE 6______________________________________Plasma concentrations of BE, ACTH, corticosterone(c/one), cortisol (c/ol) and SP-Ir in rats receivinginterrupted, continuous mode ES or sham-treatment.Treatment BE-Ir ACTH-Ir c/one-Ir c/ol-IrGroup (pg/ml) (pg/ml) (ng/ml) (ng/ml)______________________________________ * *Interrupted 215 ± 90** 373 ± 25** 1023 ± 76** 22 ± 15** (12) (6) (6) (12)Continuous 187 ± 66 778 ± 397 994 ± 266** 20 ± 4** (14) (8) (8) (6)Sham- 163 ± 76 978 ± 250** 900 ± 160** 18 ± 6**Treated (14) (8) (8) (18)Basal 145 ± 80 531 ± 244* 499 ± 165* 14 ± 6* (14) (8) (8) (6)______________________________________ Results are the mean ±SD for numbers of rats given in parentheses.
Rats received a 1800 s treatment period of one of either: Interrupted mode ES of 100s of current separated by 10s pause periods (current off), pulse width 2.0ms; Continuous mode ES identical in all respects to interrupted, except devoid of pauses; Sham-treated (with electrodes inserted but no current passed); Basal rats were killed after brief restraint (<300s) for antinociceptive testing by the TFL test. TFL determined with conductive heat challenge at 60° C. applied to the ventral surface after which the rats were killed and the blood collected.
* Significantly different (P<0.05) from sham-treated value by unpaired Student's t test.
** Significantly different (P<0.05) from basal value by unpaired Student's t test.
Comparison of impedance values with differing electrodes
Examples of electrodes applied at the ear lobes
Sharp needles which penetrate the epidermis:
(a) steel needles 77 kΩ±11 kΩ
(b) carbon needles 30 kΩ±5 kΩ
Blunt (gold button) electrodes which do not penetrate the epidermis:
Range * 300-500 kΩ
Carbonized rubber patches accurately cut to 0.5 cm diameter:
Range * without electrode gel 500 kΩ-1 mΩ
Range * with electrode gel 300-600 kΩ
* after ear lobe has been cleaned with ethanolic solution.
Examples of application
For pain amelioration
Rats received specific electrical stimulus while restrained for periods of treatment varying between 5, 10, 20, 40, 60, 120 and 180 min. The response to an acute painful challenge comprising either noxious dry heat to the tail, noxious wet heat to the tall or an intraperitoneal injection of hypertonic saline was compared with that of rats sham-treated for the similar time period and with basal (time 0) treatment.
For amelioration of drug withdrawal
Rats were addicted to morphine by implantation of miniature pumps loaded with the drug for periods varying up to 14 days. The pumps were removed and 24 hr later the abstinence effects were compared in rats receiving electrostimulus with sham-treated animals.
For amelioration of the effects of stress
Rats receiving chronic restraint stress, in some instances after prior periods of isolation stress. The neurochemical response of electrostimulated and sham-treated rats are compared.
Once efficaceous signals (which ameliorate the noxious responses in the above 3 examples ) have been identified, fresh groups of animals are subjected to that electrostimulus before humane sacrifice. After this time tissues are then assayed and the various hormonal effects associated with the efficaceous current identified by comparison of treated, sham-treated and basal (untreated and minimally-handled rats). The involvement of these neurohumoural substances is confirmed by determining the influence of prior administration of specific chemical antagonists to these neuro-hormones.
Efficaceous Currents
Packet size and pause time
At any specific frequency the optimal number of pulses per packet (ppp), and pause between succeeding packets (Dp), was determined by comparing the efficacy of the current administered at either 64, 128, 250, 500, 750, 1000, 1250, 1500, 1750, 2000, 2250, 2500 ppp with pauses (Dp) of 1, 2, 5, 10, 15, 20, 25, 50 and 100 sec between succeeding packets.
10 Hz Frequency
A prescription delivering 250 ppp and 10 sec Dp is efficaceous in providing pain relief characterized by a general feeling of drowsiness/euphoria. When prescription is administered with a Dp of 100 sec, the signal may be administered continuously (rather than for a given period of time e.g. 60 min) and is particularly efficaceous for pain control during the late evening and throughout the night. Both these 250 ppp prescriptions decrease ACTH levels while various endogenous opioids including β-endorphin (BE) are elevated in the blood.
A prescription comprising of 750 and 1000 ppp (750 providing a quantitatively greater effect for the majority of subjects) with Dp 10 sec is highly efficient as a broad range analgesic. It is especially efficaceous for inflammatory pain and where more than one type of diverse pain is present simultaneously.
This "750" prescription enhances mood and produces relaxation without drowsiness. This prescription is particularly efficaceous when administered at times when ACTH levels would be expected to be elevated, for example for people on a normal 12 h light:dark cycle, this would be the early morning, post lunch time or under conditions of extreme stress or anxiety, including the anxiety associated with chronic pain conditions. This 750 prescription decreases the turnover rate of the neurotransmitter noradrenaline for a given period. Its action may be prolonged by administering the signal in trains comprising 3 complete (with 10 sec pause) packets separated by 10 min "off" periods. Such a signal may be administered all day during the "awake period".
It is one of the most effective prescriptions for diminishing ACTH levels. The principal opiate-like effect of this prescription is on dynorphin although the magnitude and nature of this effect (on dynorphin) depends upon the time and duration for which the current is applied.
Both of these prescriptions should be applied at an amplitude of 10-12 μA under which conditions they may be used not only to control pain in the manner described an example 1 but also to assist persons habituated cigarette smoking to quit the habit, in which case the 250 ppp 10 sec prescription may also be applied at an amplitude of 30 μA.
The significance between these two prescriptions is that at 10-12 μA, both the 250 and especially the 750 ppp act by suppressing the neuronal punishment systems (see, e.g., White and Rumbold, Psychopharmacology (1988) 95: 1-14). The 750 ppp prescription inhibits the rate of noradrenaline and histamine turnover in the various brain regions, but stimulates histamine turnover in the adrenal glands where it is associated with the release of hormonal substances, principally corticosterone and opioid peptide fragments, which by feedback inhibition suppress the action of the central neurotransmitter associated with alarm or pain reactions.
Various "mixed" prescriptions e, g, an alternating 250 ppp and 750 ppp pulse packet separated by 10 s pauses (administered in a 60 min train) have been found to be particularly effective for treating inter alia pain in the head region such as trigeminal neuralgia and TMJ (temparo-mandibular joint pain),
When however the 250 ppp prescription is delivered at an amplitude of 30 μA, the inhibition of the punishment systems is less evident and the efficacy of the signal owes more to a stimulation of the reward system of the brain (see e.g. Wise, Pharmac Ther. Vol 35 pp 227-263, 1987 ). This is evidenced by enhanced turnover of neuronal dopamine and elevated BE activity. The 250 ppp may be used at 10-12 or 30 μA to ameliorate the abstinence effects of withdrawal from other drugs of abuse, inhibition of the punishment systems is more important during the early treatment (detoxication) stages, whereas enhancing the reward system of the brain is of more benefit during the rehabilitation stage of treatment.
0.1 Hz frequency
The signal may be applied continuously (with no pauses) at 10-12 μA amplitude, 2.0msec positive pulse. At this frequency the signal may be used inter alia to promote sleep or hypnosis treatment.
2 Hz frequency
The signal should be administered at 200 or 1000 ppp with 10 sec Dp at 10-12 μA amplitude, 2.0msec positive pulse. Such a current may be administered inter alia to control pain by stimulating endogenous opioid activity but it is most efficaceous in withdrawal from opiate drugs of abuse as described in example 5. This is because the current stimulates the action of the endogenous opioids which have been down regulated by the abuse of the exogenous substances.
500 Hz frequency
Both 1000 ppp at 10 sec Dp and 250 ppp at 100 sec Dp are antinociceptive and are particularly effective for ameliorating pain mediated via spinal processes. Unlike the 10 Hz prescriptions for pain relief, these prescriptions should only be administered for periods of up to 60 min with at least 180 min intervals before a succeeding stimulus, and preferably only one a day. In the early stages of detoxication from the effects of alcohol abuse, the 1000 ppp, 10 Dp prescription is administered for 24 hr basis. These prescriptions increase serotonergic activity and also stimulate histamine turnover. They decrease the narcotic effects of both barbiturates and alcohol. These prescriptions are delivered at 10-12 μA with a 1.0 ms positive pulse duration setting.
2000 Hz frequency
Administered for short periods of up to 40 min in a continuous (no Dp) train this prescription prolongs the effect, for example on narcosis of hypnotic agents. This prescription may be used in the rehabilitation/detoxication of subjects abusing hallucinogenic agents such as LSD.
Ultra fast frequency
Prescriptions administered at a number of such frequencies, in particular 1.2 and 50 MHz stimulate the punishment centers of the neuronal systems. These prescriptions should be administered in packets lasting 100 sec interspersed with 10 sec for periods of not less than 20 or more than 40 min. The number of such cycles that may be applied to the recipient will depend upon the tolerance of the individual as the current does raise anxiety levels and can impair sleeping. Since these prescriptions stimulate both cholinergic activity and the level of ACTH release, these prescriptions could be of use in the treatment of conditions involving impairment of memory such as Alzheimer's disease. The effect of ACTH is the principal mechanism by which such prescriptions may also be used to help smokers cease the practice without experiencing abstinence effects but generally the method described in example 4 is more appropriate. The stimulatory effect of these currents on ACTM may also be used therapeutically to decrease the sleeping time post-operatively following the use of narcotic agents.
Examples to illustrate treatment
EXAMPLE 1
Treatment to ameliorate pain
A subject suffering from an inflammatory pain condition would be treated with a signal at 10-12 μA of positive pulse duration 2.0 msec. At 10Hz this would be delivered in packets of 750 ppp with 10 sec Dp for a period of 60 min between 10.00-12.00 h and 14.00-16.00 h daily until pain amelioration lasting >24 h is achieved (normally 4 or 5 days ). After this time the treatment may be diminished to once daily, then once every two days, thence on demand.
EXAMPLE 2
Chronic main coupled with drug withdrawal problems when the subject ceases to use habituating drugs
The 750 ppp prescription described above may be used continuously after the subject awakens until (for most subjects on a 12 h light: dark cycle) 20.00h. The individual would then receive 2 h of the continuous 0.1 Hz prescription also at 10-12 μA and 2.0 msec positive pulse duration, followed immediately by a signal of equal amplitude and duration, but delivered at 250 ppp 10 sec Dp. This signal would be administered for I h with two hours breaks between 1 h periods of treatment. This prescription would continue until the individual awakens on the following day when the treatment would revert to the original 750 ppp prescription.
EXAMPLE 3
Chronic pain caused by lower back injury
A prescription delivered at 500 Hz at 10-12 μA amplitude and 1.0 msec positive pulse duration the first cycle comprising 1000 ppp with a 10 sec Dp alternating with a succeeding cycle 2500 ppp and 10 sec Dp the complete train should last no more than 60 min and there should be a 3 h pause before a succeeding train.
EXAMPLE 4
Amelioration of withdrawal effects in cigarette smokers who quit smoking
The minimal treatment to be administered is 60 min of a 200 ppp 10 sec Dp signal of amplitude 10-12 μA and positive pulse duration of 2.0 msec. This treatment should be administered in the morning (before noon) period. The success of the treatment in aiding people to quit smoking increases if further treatment is administered 6 h later than the first. Generally the longer the treatment period the subjects experience, the fewer (if any) abstinence effects are observed. Persons experiencing depressive symptoms should receive 40 min treatment with the same signal at 30 μA amplitude. This latter treatment should not be administered within 2 h of a previous treatment. This treatment to enable people to cease smoking should continue a minimum of to a maximum of 7 days. The treatment should be administered with the appropriate behavioural modification therapy.
EXAMPLE 5
Amelioration of abstinence symptoms during withdrawal of drugs of abuse (including alcohol) of addicted subjects
This may be achieved by administering a prescription which enhances the neurochemical reward systems e.g. 250 ppp, 10 sec Dp, 2.0msec positive pulse at 30 μA amplitude, or inhibits the neurochemical punishment system e.g. 750 ppp, 10 sac Dp, 2.0 msec positive pulse at 10-12 μA amplitude. Whichever of these prescriptions is applied, the treatment should still only be administered for i h in the morning and 1 h in the afternoon period. In between these treatments and up until 20.00h, the subject should receive trains of the 750 ppp prescription consisting of three packets separated by a 10 min train pause. After 20.00h the subject may be maintained during the sleep phase with either a 250 ppp, 100sec Dp, 2.0msec positive pulse duration, 10 Mr, 10-12 μA amplitude or a continuous 0.1Hz prescription of positive pulse duration 2.0msec and 10-12 μA amplitude.
The period that the treatments are administered will depend upon the stage of withdrawal from drugs of the subject and the quantity (and duration of abuse). This treatment represents the detoxication phase which would normally be expected to last no more than 3-5 days the recipient should be available for psychotherapy/counselling at the end of this phase. Thereafter the subject should receive a further 7-10 days of a prescription delivered at 2 Hz, 200 ppp, Dp, 2.0msec positive pulse duration at an amplitude of 10-12 μA. This prescription should be administered for 60min periods alternating with 60 min periods when no treatment is applied. After 7 days this treatment should be scaled down so that the subject receives no more than 2 treatments per day. 14 days after beginning the original treatment, the subject should not exhibit any abstinence symptoms i f no treatment is administered at all. This latter prescription may be administered on a no more than twice a day basis to aid in the psychological rehabilitation process over the succeeding months however.
In the case of detoxication from heroin or other opiate addictions, a prescription delivered at 133 Hz, 10-12 μA amplitude, 2.0msec positive pulse duration comprising packets of 2500 ppp and 10 sec Dp is particularly effective during the daylight hours.
In the case of alcohol abuse a 500 Hz prescription comprising 1000 ppp, 10 sec Dp with positive pulse duration 1.0 msec of amplitude 10-12 μA is effective in the detoxication stage but should be administered during the light period of the day only. If the subject is unable to sleep they may be treated at night in the manner described above for the other chemical addictions.
Other applications
From knowledge of the action of TCET on various neurohumoural processes it is reasonable to assume that the treatment could be beneficially applied to other medical problems including:
1. Immune dysfunction
By controlling corticosteroid levels by modulating ACTH release from the pituitary, lowering the concentration of blood dynorphin and adrenal histamine, the autoimmune defence mechanisms responsible for the inflammatory reactions in conditions like rheumatoid arthritis could be controlled, with the appropriate prescription.
2. Parkinson's disease
In the early stages of this condition, the dopaminergic activity of central neural system is enhanced by TCET.
3. Alzheimer's disease
There is evidence that the cholinergic activity in the frontal lobes is increased by the appropriate prescription. It therefore follows that as with Parkinson's disease, provided that the tissues to be treated have not deteriorated excessively (i.e. in the early stages of the condition) it is likely that TCET could retard the deterioration of the neurons by boosting the activity of the appropriate neurotransmitters.
4. Depression
Marked enhancements of mood have been observed when treating subjects with some prescriptions to alleviate pain. Since these prescriptions modulate the tone of neurotransmitters associated with behavior, and the level and release of ACTH may also be suppressed with the appropriate prescription, it is reasonable to assume that TCET would be efficaceous for the treatment of various forms of depression.
5. Insomnia/Jet lag
TCET has been demonstrated to decrease the secretion of ACTH in both experimental and clinical conditions, and this neurohormone is concerned inter alia with the process of awakening. It is probable that suppression of this hormone will aid the sleep process, especially if coupled with prescriptions which reduce anxiety by lowering noradrenergic tone. It also follows that supression of this substance at specific times of day could help offset the shift in diurnal/circadian rhythm "jet-lag" associated with travel between time zones.
6. Stress/anxiety phobias
Some prescriptions have an anti-anxiety component in the mode of action in ameliorating pain and when suppressing noradrenaline turnover, some prescriptions have also enabled habituated subjects to cease using anxiolytic substances. It therefore follows that such prescriptions could be used to replace anxiolytic drugs for the control of stress/anxiety situations. It is also possible that such treatment would be beneficial for subjects suffering from behavioural abnormalities such as schizophrenia.
7. Neurological dysfunction
Enhancement of the release of neurotransmitters involved in motor control could be beneficial in various conditions such as epilepsy, muscular sclerosis, muscular dystrophy, etc.
8. Appetite disturbance
Stimulating the secretion of various opioid peptides while inhibiting other peptidergic substances such as ACTH and cholecystokinin (CCK) could be used to stimulate appetite in individuals suffering from anorexia nervosa. Conversely inhibiting opioid peptides should suppress appetite in individuals who overeat. It therefore follows that TCET administered at the appropriate time of day could be used to suppress or enhance appetite.
9. Sexual dysfunction
In some cases of erectile impotence TCET could be used to stimulate the parasympathetic, while inhibiting the sympathetic nervous system.
Similarly, amenorrhea/dysmenorrhea with origins in stress and concomitantly elevated prolactin secretion may be attenuated by stimulating dopaminergic and opioid pathways at specific intervals in the menstrual cycle so regulating menses.
10. Anaesthesia adjunct
Some prescriptions increase and others diminish the effects of an acute dose of hypnotic substances. Therefore TCET introduced post-operatively for pain control could also lower the amount of anaesthetic necessary to maintain the patient during operations and thence enable the patient to rapidly recover from the anaesthetic post-operatively as well as controlling post operative pain.
11. Detoxication
A side-effect of TCET is the stimulation of hepatic function as the result of increased hypothamo-pituitary activity. This can be useful for the clearance of drugs and toxic substances from the individual and could also be useful to protect kidney function in the case of deliberate acute drug overdose.
Detailed description of ear clip electrode
According to one aspect, the present invention provides a bifurcated electrode assembly comprising two arms between which an ear or other fleshy body part can be gripped; Biasing means, such as a threaded screw, arranged for biasing the two arms together so as to grip the ear etc., a threaded electrode carrier being mounted in a passage of one of the arms for advancement towards to ear. Preferably locking means are provided for locking the electrode carrier against rotation. The electrode carrier preferably has a threaded split collet with a blind hole in which an electrode needle can be gripped. Alternatively, the electrode needle can be permanently mounted in the carrier, e.g. by being molded in situ.
According to another aspect, the invention provides a head support device for supporting a pair of electrode assemblies, comprising a resilient wire or the like having a U-shaped portion shaped to fit from the tops of the ears round the nape of the neck, and a pair of end portions shaped to descend generally vertically from the top front of the ears and to each of which an electrode assembly can be attached.
The electrode assembly preferably includes a pivoted bracket for attachment to the head support device.
These and other significant features of the invention will become apparent from the following description of a skin electrode mounting system embodying the invention, given by way of example, with reference to the drawings:
FIG. 1 is a general view of an electrode assembly 10. A base portion 1 has two major arms 12 and 13 extending from it, forming a pair of jaws to be placed around the lobe or other desired part of the ear. A bolt 14 is mounted in arm 12 and engages in a threaded hole in the arm 13, so that by turning its head 15, the arms 12 and 13 can be moved together to grip the chosen part of the ear. The facing parts of the ends of the arms 12 and 13 are grooved or serrated to give a good grip. The natural positions of the arms 12 and 13 may be sufficiently divergent that the gap between their outer ends is wider than the maximum thickness of the ear. Alternatively, the arms 12 and 13 may be formed so that in their natural or unstressed condition, the gap between their ends is that of a typical ear lobe. I f that is so, the screw 14 must be able to pull the arms together and force them apart. This can be achieved by providing the screw 14 with a collar (not shown) attached to it adjacent to the inner side of the arm 12.
An electrode carrier 16 is mounted in a threaded hole towards the end of arm 12. The hole is deepened by a collar 17. As shown in FIGS. 2 and 3, the assembly 10 can comprise a single plastic molding which is bent in two by virtue of a narrower flexible middle section 18.
The electrode carrier 16 is illustrated in FIG. 4. It comprises a short, relatively thick screw having a knurled or ribbed head 19 and an axially mounted electrode needle 20 having a pointed end 21 and a distal end 22 onto which an electric lead can be connected by a crimped ferrule connector or the like. Optionally, carrier 16 can be fitted with a locking nut (not shown) to prevent rotation. Also, calibration can be provided, so that the same degree of advancement of the needle 20 can be achieved on different occasions.
Apparatus for generating a suitable signal is described, for example, in International Patent Application No. WO 86/02567. Alternatively, a power supply circuit and signal generator are shown in FIGS. 5 to 7. | An electrode for providing TCET, especially via the earlobes of the patient, comprises an electrical conductor for application to the skin, connected to a lead for supplying the TCET signal from a signal generating device, characterized in that the conductor comprises a generally conical needle point capable of penetrating the epidermis so as to provide good electrical contact over a very small area. The electrode can be used in the impedance of less than 100 kΩ; and with apparatus for generating an electrical signal for use in TCET, adapted to provide a signal at a current of less than 200 μA (0.2 mA), especially when adapted to provide an AC signal in which each positive pulse is relatively short and high without being spiked and the following negative pulse is relatively wide and low, the total amount of positive and negative charge being balanced. Methods of providing TCET treatment to patients using the electrode and apparatus are also provided. | 8 |
BACKGROUND OF THE INVENTION
[0001] In the early 1960's, zymosan, a crude insoluble yeast extract prepared by boiling yeast before and after trypsin treatment, was noted to produce marked hyperplasia and functional stimulation of the raticuloendothelial system in rodents. In animal studies; zymosan preparations were shown to inactivate complement component C3, to enhance antibody formation, to promote survival following irradiation, to increase resistance to bacterial infections, to inhibit tumor development, to promote graft rejection, and to inhibit dietary-induced hypercholesterolemia and cholesterosis. Zymosan was shown to consist of polysacoharides, proteins, fats, and inorganic elements; however, subsequent studies identified the active components of the yeast cell wall as a pure polysaccharide, specifically β-glucan. In conventional nomenclature, the polysaccharide β-glucan is known as poly-(1-6)-β-O-glucopyranosyl-(1-3)-β-D-glucopyranose (PGG). Repetition of biological assays with β-glucan indicated that most of the above functional activities identified with zymosan were retained by the purified β-glucan preparation.
[0002] The properties of β-glucan are quite similar to those of endotoxin in increasing nonspecific immunity and resistance to infection. The activities of β-glucan as an immune adjuvant and hemopoietic stimulator compare to those of more complex biological response modifiers (BRMs), such as bacillus Calmette-Guerin (BCG) and Corynebacterium parvum. The functional activities of yeast β-glucan are also comparable to those structurally similar carbohydrate polymers isolated from fungi and plants. These higher molecular weight (1-3)-β-D-glucans such as schizophyllan, lentinan, krestin, grifolan, and pachyman exhibit similar immunomodulatory activities. A common mechanism shared by all these β-glucan preparations is their stimulation of cytokines such as interleukin-1 (IL-1) and tumor necrosis factor (TNF). Lentinan has been extensively investigated for its antitumor properties, both in animal models at 1 mg/kg for 10 days and in clinical trials since the late 1970's in Japan for advanced or recurrent malignant lymphoma and colorectal, mammary, lung and gastric cancers. In cancer chemotherapy, lentinan has been administered at 0.5-5 mg/day, intramuscularly (I. M.) or intravenously (I. V.), two or three times per week alone, or in combination with antineoplastic drugs. In addition to the activities ascribed to yeast glucans, studies suggest lentinan acts as a T-cell immunopotentiator, inducing cytotoxic activities, including production of interleukins 1 and 3 and colony-stimulating factors (CSF). (Chihara et al., 1989, Int. J. Immunotherapy, 4:145-154; Hamuro and Chihara, In Lentinan, An Immunopotentiator )
[0003] Various preparations of both particulate and soluble β-glucans have been tested in animal models to evaluate biological activities. The use of soluble and insoluble β-glucans alone or as vaccine adjuvants for viral and bacterial antigens has been shown in animal models to markedly increase resistance to a variety of bacterial, fungal, protozoan and viral infections. The hemopoietic effects of β-glucan have been correlated with increased peripheral blood leukocyte counts and bone marrow and splenic cellularity, reflecting increased numbers of granulocyte-macrophage progenitor cells, splenic pluripotent stem cells, and erythroid progenitor cells, as well as, increased serum levels of granulocyte-monocyte colony-stimulating factor (GM-CSF). Furthermore, the hemopoietic and anti-infective effects of β-glucan were active in cyclophosphamide-treated immunosuppressed animals. β-glucan was shown to be beneficial in animal models of trauma, wound healing and tumorigenesis. However, various insoluble and soluble preparations of β-glucan differed significantly ink biological specificity and potency, with effective dosages varying from 25-to 500 mg/kg intravenously or intraperitoneally (I. P.) in models for protection against infection and for hemopoiesis. Insoluble preparations demonstrated undesirable toxicological properties manifested by hepatosplenomegaly and granuloma formation. Clinical interest was focused on a soluble glucan preparation which would retain biological activity yet yield negligible toxicity when administered systemically. Chronic systemic administration of a soluble phosphorylated glucan over a wide range of doses (40-1000 mg/kg) yielded negligible toxicity in animals (DiLuzio et al., 1979, lnt. J. of Cancer, 24:773-779; DiLuzio, U.S. Pat. No. 4,739,046).
[0004] The molecular mechanism of action of β-glucan has been elucidated by the demonstration of specific β-glucan receptor binding sites on the cell membranes of human neutrophils and macrophages. Mannans, galactans, α(1-4)-linked glucose polymers and β(1-4)-linked glucose polymers have no avidity for this receptor. These β-glucan binding sites are opsonin-independent phagocytic receptors for particulate activators of the alternate complement pathway, similar to Escherichia coli lipopolysaccharide (LPS) and some animal red blood cells. Ligand binding to the β-glucan receptor, in the absence of antibody, results in complement activation, phagocytosis, lysosomal enzyme release, and prostaglandin, thromboxane and leukotriene generation; thereby increasing nonspecific resistance to infection. However, soluble β-glucan preparations described in the prior art demonstrated stimulation of cytokines. Increases in plasma and splenic levels of interleukins 1 and 2 (IL-1, IL-2) in addition to TNF were observed in vivo and corresponded to induction of the synthesis of these cytokines in vitro. (See Sherwood et al., 1987, Int. J. Immunopharmac., 9:261-267 (enhancement of IL-1 and IL-2 levels in rats injected with soluble glucan); Williams et al., 1988, Int. J. Immunopharmac., 10:405-414 (systemic administration of soluble glucan to AIDS patients increased IL-1 and IL-2 levels which were accompanied by chills and fever); Browder et al., 1990, Ann. Sure, 211:605-613 (glucan administration to trauma patients increased serum IL-1 levels, but not TNF levels); Adachi et al., 1990, Chem. Pharm. Bull., 38:988-992 (chemically cross-linked β(1-3) glucans induced IL-1 production in mice).)
[0005] Interleukin-1 is a primary immunologic mediator involved in cellular defense mechanisms. Numerous studies have been carried out on the application of IL-1 to enhance non-specific resistance to infection in a variety of clinical states. Pomposelli et al., J. Parent. Ent. Nutr. 12(2):212-218, (1988). The major problem associated with the excessive stimulation or exogenous administration of IL-1 and other cellular mediators in humans is toxicity and side effects resulting from the disruption of the gentle balance of the immunoregulatory network. Fauci et al., Ann. Int. Med., 106:421-433 (1987). IL-1 is an inflammatory cytokine that has been shown to adversely affect a variety of tissues and organs. For instance, recombinant IL-1 has been shown to cause death, hypotensive shock, leukopenia, thrombocytopenia, anemia and lactic acidosis. In addition, IL-1 induces sodium excretion, anorexia, slow wave sleep, bone resorption, decreased pain threshold and expression of many inflammatory-associated cytokines. It is also toxic to the insulin secreting beta cells of the pancreas. Patients suffering from a number of inflammatory diseases have elevated levels of IL-1 in their systems. Administration of agents that enhance further IL-1 production only exacerbate these inflammatory conditions.
[0006] Tumor necrosis factor is also involved in infection, inflammation and cancer. Small amounts of TNF release growth factors while in larger amounts, TNF can cause septic shock, aches, pains, fever, clotting of blood, degradation of bone and stimulation of white blood cells and other immune defenses.
SUMMARY OF THE INVENTION
[0007] The present invention relates to neutral soluble β-glucans which enhance a host's immune defense mechanisms to infection but do not induce an inflammatory response, to preparations containing the neutral soluble β-glucans, and to a novel manufacturing process therefor. In the present method, soluble glucan which induces cytokine production is processed through a unique series of acid, alkaline and neutral treatment steps to yield a conformationally pure neutral soluble glucan preparation with unique biological properties. The neutral soluble glucan preparation retains a specific subset of immunological properties common to β-glucans but uniquely does not induce the production of IL-1 and TNF in vitro or in vivo. Throughout this specification, unless otherwise indicated, the expressions “neutral soluble glucan” and “neutral soluble β-glucan” refer to the composition prepared as described in Example 1.
[0008] The neutral soluble glucan preparation is produced by treating insoluble glucan with acid to produce a water soluble glucan, dissociating the native conformations of the soluble glucan at alkaline pH, purifying the desired molecular weight fraction at alkaline pH, re-annealing the dissociated glucan fraction under controlled conditions of time, temperature and pH to form a unique triple helicaal conformation, and further purifying under neutral pH to remove single helix and aggregated materials to yield a conformationally pure, neutral, water soluble, underivatized glucan which has a unique biological profile.
[0009] The neutral soluble glucan preparation has a high affinity for the β-glucan receptor of human monocytes and retains two primary biological activities, (1) the enhancement of microbicidal activity of phagocytic cells, and (2) monocyte, neutrophil and platelet hemopoietic activity. Unlike soluble glucans described in the prior art, the neutral soluble glucan of this invention neither induces nor primes mononuclear cells to increase IL-1 and TNF production in vitro and in vivo.
[0010] The neutral soluble glucan preparation is appropriate for parenteral (e.g., intravenous, intraperitoneal, subcutaneous, intramuscular), topical, oral or intranasal administration to humans and animals as an anti-infective to combat infection associated with burns, surgery, chemotherapy, bone marrow disorders and other conditions in which the immune system may be compromised. Neutral soluble glucan produced by the present method can be maintained in a clear solution and equilibrated in a pharmaceutically acceptable carrier. Safe and efficacious preparations of the neutral soluble glucan of the present invention can be used in therapeutic and/or prophylactic treatment regimens of humans and animals to enhance their immune response, without stimulating the production of certain biochemical mediators (e.g., IL-1 and TNF) that can cause detrimental side effects, such as fever and inflammation.
BRIEF DESCRIPTION OF THE FIGURES
[0011] [0011]FIG. 1 shows the general structure of neutral soluble glucan as being a linear β(1-3)-linked glucose polymer having periodic branching via a single β(1-6)-linked glucose moiety.
[0012] [0012]FIG. 2 shows a gel permeation chromatogram (pH 7) of soluble glucan which has not been purified by alkali dissociation and re-annealing. The chromatogram shows three species, referred to herein as high molecular weight aggregate (Ag), Peak A and Peak B (single helix glucan).
[0013] [0013]FIG. 3 is a chromatogram obtained for the neutral soluble glucan by gel permeation chromatography. The solid line represents the neutral soluble glucan at pH 7 and the broken line represents the neutral soluble glucan at pH 13.
[0014] [0014]FIG. 4 is a chromatogram obtained for the single helix β-glucan (Peak B) by gel permeation chromatography. The solid line represents Peak B at pH 7 and the broken line represents Peak B at pH 13.
[0015] [0015]FIG. 5 shows the change in serum IL-1 levels, over time, taken from patients intravenously infused with placebo (broken line) or neutral soluble glucan (solid line).
[0016] [0016]FIG. 6 shows the change in serum TNF levels, over time, taken from patients intravenously infused with lacebo (broken line) or neutral soluble glucan (solid line).
[0017] [0017]FIG. 7 is a diagram representing peripheral blood counts from irradiated mice following administration of neutral soluble glucan.
[0018] [0018]FIG. 8 is a diagram representing platelet cell counts from cisplatin-treated mice following administration of neutral soluble glucan.
DETAILED DESCRIPTION OF INVENTION
[0019] The invention relates to a neutral soluble β-glucan polymer that can bind to the β-glucan receptor and activate only a desired subset of immune responses. The terms “neutral soluble β-glucan” and “neutral soluble glucan”, unless otherwise specified, refer to the composition prepared as described in Example 1.
[0020] This neutral soluble β-glucan has been shown to increase the number of neutrophils and monocytes as well as their direct infection fighting activity (phagocytosis and microbial killing). However, the neutral soluble β-glucan does not stimulate the production of biochemical mediators, such as IL-1 and TNF, that can cause detrimental side effects such as high fever, inflammation, wasting disease and organ failure. These advantageous properties make neutral soluble glucan preparations of this invention useful in the prevention and treatment of infection because they selectively activate only those components of the immune system responsible for the initial response to infection, without stimulating the release of certain biochemical mediators that can cause adverse side effects. The solution containing the neutral soluble β-glucan also lacks the toxicity common to many immunomodulators.
[0021] The neutral soluble β-glucans of this invention are composed of glucose monomers organized as a β(1-3) linked glucopyranose backbone with periodic branching via β(1-6) glycosidic linkages. The neutral soluble glucan preparations contain glucans, which have not been substantially modified by substitution with functional (e.g., charged) groups or other covalent attachments. The general structure of the neutral soluble glucan is shown in FIG. 1. The biologically active preparation of this invention is a conformationally purified form of β-glucan produced by dissociating the native glucan conformations and re-annealing and purifying the resulting unique triple helical conformation. The unique conformation of the neutral soluble glucan contributes to the glucan's ability to selectively activate the immune system without stimulating the production of detrimental biochemical mediators.
[0022] The neutral soluble glucan preparations of this invention are prepared from insoluble glucan particles, preferably derived from yeast organisms. See Manners et al., Biochem. J., 135:19-30, (1973) for a general procedure to make insoluble yeast glucans. Glucan particles which are particularly useful as starting materials in the present invention are whole glucan particles (WGP) described by Jamas et al., in U.S. Pat. Nos. 4,810,646, 4,992,540, 5,082,936 and 5,028,703, the teachings of all of which are hereby incorporated herein by reference. The source of the whole glucan particles can be the broad spectrum of glucan-containing yeast organisms which contain β-glucans in their cell walls. Whole glucan particles obtained from the strains Saccharomyces cerevisiae R4 (NRRL Y-15903; deposit made in connection with U.S. Pat. No. 4,810,646) and R4 Ad (ATCC No. 74181) are particularly useful. Other strains of yeast that can be used include Saccharomyces delbrueckii, Saccharomyces rosei, Saccharomyces microellinsodes, Saccharomyces carlsbercensis, Schizosacharomyces pombe, Kluyveromycies lactis, Kluyveromyces fragilis, Kluyveromyces polysporus, Candida albicans, Candida cloacae, Candida troipicalis, Candida utilis, Hansenula wingeri, Hansenula arni, Hansenula henricii, Hansenula americana.
[0023] A procedure for extraction of whole glucan particles is described by Jamas et al., in U.S. Pat. Nos. 4,810,646, 4,992,540, 5,082,936 and 5,028,703. For the purpose of this present invention, it is not necessary to conduct the final organic extraction and wash steps described by Jamas et al.
[0024] In the present process, whole glucan particles are suspended in an acid solution under conditions sufficient to dissolve the acid-soluble glucan portion. For most glucans, an acid solution having a pH of from about 1 to about 5 and at a temperature of from about 20 to about 100° C. is sufficient. Preferably, the acid used is an organic acid capable of dissolving the acid-soluble glucan portion. Acetic acid, at concentrations of from about 0.1 to about 5 M or formic acid at concentrations of from about 50% to 98% (w/v) are useful for this purpose. The treatment time may vary from about 10 minutes to about 20 hours depending on the acid concentration, temperature and source of whole glucan particles. For example, modified glucans having more (1-6) branching than naturally-occurring, or wild-type glucans, require more stringent conditions, i.e., longer exposure times and higher temperatures. This acid-treatment step can be repeated under similar or variable conditions. One preferred processing method is described in the exemplification using glucan derived from S. cerevisiae strain R4 Ad. In another embodiment of the present method, whole glucan particles from the strain, S. cerevisiae R4, which have a higher level of β(1-6) branching than naturally-occurring glucans, are used, and treatment is carried out with 90% (w/v) formic acid at 20° C. for about 20 minutes and then at 85° C. for about 30 minutes.
[0025] The insoluble glucan particles are then separated from the solution by an appropriate separation technique, for example, by centrifugation or filtration. The pH of the resulting slurry is adjusted with an alkaline compound such as sodium hydroxide, to a pH of about 7 to about 14. The precipitate is collected by centrifugation and is boiled in purified water (e.g., USP) for three hours. The slurry is then resuspended in hot alkali having a concentration sufficient to solubilize the glucan polymers. Alkaline compounds which can be used in this step include alkali-metal or alkali-earth metal hydroxides, such as sodium hydroxide or potassium hydroxide, having a concentration of from about 0.01 to about 10 N. This step can be conducted at a temperature of from about 40° C. to about 121° C., preferably from about 20° C. to about 100° C. In one embodiment of the process, the conditions utilized are a 1 M solution of sodium hydroxide at a temperature of about 80-100° C. and a contact time of approximately 1-2 hours. The resulting mixture contains solubilized glucan molecules and particulate glucan residue and generally has a dark brown color due to oxidation of contaminating proteins and sugars. The particulate residue is removed from the mixture by an appropriate separation technique, e.g., centrifugation and/or filtration. In another embodiment of the process the acid-soluble glucans are precipitated after the preceding acid hydrolysis reaction by the addition of about 1.5 volumes of ethanol. The mixture is chilled to about 4° C. for two (2) hours and the resulting precipitate is collected by centrifugation or filtration and washed with water. The pellet is then resuspended in water, and stirred for three (3) to twelve (12) hours at a temperature between about 20° C. and 100° C. At this point the pH is adjusted to approximately 10 to 13 with a base such as sodium hydroxide.
[0026] The resulting solution contains dissociated soluble glucan molecules. This solution is now purified to remove traces of insoluble glucan and high molecular weight soluble glucans which can cause aggregation. This step can be carried out by an appropriate purification technique, for example, by ultrafiltration, utilizing membranes with nominal molecular weight (NMW) levels or cut-offs in the range of about 1,000 to 100,000 daltons. It was discovered that in order to prevent gradual aggregation or precipitation of the glucan polymers the preferred membrane for this step has a nominal molecular weight cut-off of about 100,000 daltons. The soluble glucan is then further purified at alkaline pH to remove low molecular weight materials. This step can be carried out by an appropriate purification technique, for example, by ultrafiltration, utilizing membranes with nominal molecular weight levels or cut-offs in the range of 1,000 to 30,000 daltons.
[0027] The resulting dissociated soluble glucan is re-annealed under controlled conditions of time (e.g., from about 10 to about 120 minutes), temperature (e.g., from about 50 to about 70° C.) and pH. The pH of the solution is adjusted to the range of about 3.5-11 (preferably 6-8) with an acid, such as hydrochloric acid. The purpose of this re-annealing step is to cause the soluble glucan to rearrange from a single helix conformation to a new ordered triple helical conformation. The re-annealed glucan solution is then size fractionated, for example by using 30,000-70,000 NMW and 100,000-500,000 NMW cut-off membrane ultrafilters to selectively remove high and low molecular weight soluble glucans. Prior to sizing, the soluble glucans exist as a mixture of conformations including random coils, gel matrices or aggregates, triple helices and single helices. The objective of the sizing step is to obtain an enriched fraction for the re-annealed conformation of specific molecular weight. The order in which the ultrafilters are used is a matter of preference.
[0028] The concentrated fraction obtained is enriched in the soluble, biologically active neutral soluble glucan. The glucan concentrate is further purified, for example, by diafiltration using a 10,000 dalton membrane. The preferred concentration of the soluble glucan after this step is from about 2 to about 10 mg/ml.
[0029] The neutralized solution can then be further purified, for example, by diafiltration, using a pharmaceutically acceptable medium (e.g., sterile water for injection, phosphate-buffered saline (PBS) , isotonic saline, dextrose) suitable for parenteral administration. The preferred membrane for this diafiltration step has a nominal molecular weight cut-off of about 10,000 daltons. The final concentration of the glucan solution is adjusted in the range of about 0. 5 to 10 mg/ml. In accordance with pharmaceutical manufacturing standards for parenteral products, the solution can be terminally sterilized by filtration through a 0.22 μm filter. The neutral soluble glucan preparation obtained by this process is sterile, non-antigenic, essentially pyrogen-free, and can be stored at room temperature (e.g., 15-30° C.) for extended periods of time without degradation. This process is unique in that it results in a neutral aqueous solution of (pH 4.5 to 7.0) immunologically active glucans which is suitable for parenteral administration.
[0030] For purposes of the present invention, the term “soluble” as used herein to describe glucans obtained by the present process, means a visually clear solution can be formed in an aqueous medium such as water, PPBS, isotonic saline, or a dextrose solution having a neutral pH (e.g., from about pH 5 to about 7.5), at room temperature (about 20-25° C.) and at a concentration of up to about 10 mg/ml. The term “aqueous medium” refers to water and water-rich phases, particularly to pharmaceutically acceptable aqueous liquids, including PBS, saline and dextrose solutions. The expression “visually clear” means that at a concentration of a mg/ml, the absorption of the solution at 530 nm is less than OD 0.01 greater than the OD of an otherwise identical solution lacking the B-glucan component.
[0031] The resulting solution is substantially free of protein contamination, is non-antigenic, non-pyrogenic and is pharmaceutically acceptable for parenteral administration to animals and humans. However, if desired, the soluble glucan can be dried by an appropriate drying method, such as lyophilization, and stored in dry form.
[0032] The neutral soluble glucans of this invention can be used as safe, effective, therapeutic and/or prophylactic agents, either alone or as adjuvants, to enhance the immune response in humans and animals. Soluble glucans produced by the present method selectively activate only those components that are responsible for the initial response to infection, without stimulating or priming the immune system to release certain biochemical mediators (e.g., IL-1, TNF, IL-6, IL-8 and GM-CSF) that can cause adverse side effects. As such, the present soluble glucan composition can be used to prevent or treat infectious diseases, in malnourished patients, patients undergoing surgery and bone marrow transplants, patients undergoing chemotherapy or radiotherapy, neutropenic patients, HIV-infected patients, trauma patients, burn patients, patients with chronic or resistant infections such as those resulting from myeiodysplastic syndrome, and the elderly, all of who may have weakened immune systems. An immunocompromised individual is generally defined as a person who exhibits an attenuated or reduced ability to mount, a normal cellular and/or humoral defense to challenge by infectious agents, e.g., viruses, bacteria, fungi and protozoa. A protein malnourished individual is generally defined as a person who has a serum albumin level of less than about 3.2 grams per deciliter (g/dl) and/or unintentional weight loss of greater than 10% of usual body weight.
[0033] More particularly, the method of the invention can be used to therapeutically or prophylactically treat animals or humans who are at a heightened risk of infection due to imminent surgery, injury, illness, radiation or chemotherapy, or other condition which deleteriously affects the immune system. The method is useful to treat patients who have a disease or disorder which causes the normal metabolic immune response to be reduced or depressed, such as HIV infection (AIDS). For example, the method can be used to pre-initiate the metabolic immune response in patients who are undergoing chemotherapy or radiation therapy, or who are at a heightened risk for developing secondary infections or post-operative complications because of a disease, disorder or treatment resulting in a reduced ability to mobilize the body's normal metabolic responses to infection. Treatment with the neutral soluble glucans has been shown to be particularly effective in mobilizing the host's normal immune defenses, thereby engendering a measure of protection from infection in the treated host.
[0034] The present-composition is generally administered to an animal or a human in an amount sufficient to produce immune system enhancement. The mode of administration of the neutral soluble glucan can be oral, enteral, parenteral, intravenous, subcutaneous, intraperitoneal, intramuscular, topical or intranasal. The form in which the composition will be administered (e.g., powder, tablet, capsule, solution, emulsion) will depend upon the route by which it is administered. The quantity of the composition to be administered will be determined on an individual basis, and will be based at least in part on consideration of the severity of infection or injury in the patient, the patient's condition or overall health, the patient's weight and the time available before surgery, chemotherapy or other high-risk treatment. In general, a single dose will preferably contain approximately 0.01 to approximately 10 mg of modified glucan per kilogram of body weight, and preferably from about 0.1 to 2.5 mg/kg. The dosage for topical application will depend upon the particular wound to be treated, the degree of infection and severity of the wound. A typical dosage for wounds will be from about 0.001 mg/ml to about 2 mg/ml, and preferably from about 0.01 to about 0.5 mg/ml.
[0035] In general, the compositions of the present invention can be administered to an individual periodically as necessary to stimulate the individual's immune response. An individual skilled in the medical arts will be able to determine the length of time during which the composition is administered and the dosage, depending upon the physical condition of the patient and the disease or disorder being treated. As stated above, the composition may also be used as a preventative treatment to preinitiate the normal metabolic defenses which the body mobilizes against infections.
[0036] Neutral soluble β-glucan can be used for the prevention and treatment of infections caused by a broad spectrum of bacterial, fungal, viral and protozoan pathogens. The prophylactic administration of neutral soluble β-glucan to a person undergoing surgery, either preoperatively, intraoperatively and/or post-operatively, will reduce the incidence and severity of post-operative infections in both normal and high-risk patients. For example, in patients undergoing surgical procedures that are classified as contaminated or potentially contaminated (e.g., gastrointestinal surgery, hysterectomy, cesarean section, transurethral prostatectomy) and in patients in whom infection at the operative site would present a serious risk (e.g., prosthetic arthroplasty, cardiovascular surgery), concurrent initial therapy with an appropriate antibacterial agent and the present neutral soluble glucan preparation will reduce the incidence and severity of infectious complications.
[0037] In patients who are immunosappressed, not only by disease (e.g., cancer, AIDS) but by courses of chemotherapy and/or radiotherapy, the prophylactic administration of the soluble glucan will reduce the incidence of infections caused by a broad spectrum of opportunistic pathogens including many unusual bacteria, fungi and viruses. Therapy using neutral soluble β-glucan has demonstrated a significant radio-protective effect with its ability to enhance and prolong macrophage function and regeneration and, as a result enhance resistance to microbial invasion and infection.
[0038] In high risk patients (e.g., over age 65, diabetics, patients having cancer, malnutrition, renal disease, emphysema, dehydration, restricted mobility, etc.) hospitalization frequently is associated with a high incidence of serious nosocomial infection. Treatment with neutral soluble β-glucan may be started empirically before catheterization, use of respirators, drainage tubes, intensive care units, prolonged hospitalizations, etc. to help prevent the infections that are commonly associated with these procedures. Concurrent therapy with antimicrobial agents and the neutral soluble β-glucan is indicated for the treatment of chronic, severe, refractory, complex and difficult to treat infections.
[0039] The compositions administered in the method of the present invention can optionally include other components, in addition to the neutral soluble β-glucan. The other components that can be included in a particular composition are determined primarily by the manner in which the composition is to be administered. For example, a composition to be administered orally in tablet form can include, in addition to neutral soluble β-glucan, a filler (e.g., lactose), a binder (e.g., carboxymethyl cellulose, gum arabic, gelatin), an adjuvant, a flavoring agent, a coloring agent and a coating material (e.g., wax or plasticizer). A composition to be administered in liquid form can include neutral soluble β-glucan and, optionally, an emulsifying agent, a flavoring agent and/or a coloring agent. A composition for parenteral administration can be mixed, dissolved or emulsified in water, sterile saline, PBS, dextrose or other biologically acceptable carrier. A composition for topical admihistration can be formulated into a gel, ointment, lotion, cream or other form in which the composition is capable of coating the site to be treated, e.g., wound site.
[0040] Compositions comprising neutral soluble glucan can also be administered topically to a wound site to stimulate and enhance wound healing and repair. Wounds due to ulcers, acne, viral infections, fungal infections or periodontal disease, among others, can be treated according to the methods of this invention to accelerate the healing process. Alternatively, the neutral soluble β-glucan can be infected into the wound or afflicted area. In addition to wound repair, the composition can be used to treat infection associated therewith or the causative agents that result in the wound. A composition for topical administration can be formulated into a gel, ointment, lotion, cream or other form in which the composition is capable of coating the site to be treated, e.g., wound site. The dosage for topical application will depend upon the particular wound to be treated, the degree of infection and severity of the wound. A typical dosage for wounds will be from about 0.01 mg/ml to about 2 mg/ml, and preferably from about 0.01 to about 0.5 mg/ml.
[0041] Another particular use of the compositions of this invention is for the treatment of myeiodysplastic syndrome (IDS). MDS, frequently referred to as preleukemia syndrome, is a group of clonal hematopoietic stem cell disorders characterized by abnormal bone marrow differentiation and maturation leading to peripheral cytopenia with high probability of eventual leukemic conversion. Recurrent infection, hemorrhaging and terminal infection resulting in death typically accompany MDS. Thus, in order to reduce the severity of the disease and the frequency of infection, compositions comprising modified glucan can be chronically administered to a patient diagnosed as having MDS according to the methods of this invention, in order to specifically increase the infection fighting activity of the patient's white blood calls. Other bone marrow disorders, such as a plastic anemia (a condition of quantitatively reduced and defective hematopciesis) can be treated to reduce infection and hemorrhage that are associated with this disease state.
[0042] Neutral soluble glucan produced by the present method enhances the non-specific defenses of mammalian mononuclear cells and significantly increases their ability to respond to an infectious challenge. The unique property of neutral soluble glucan macrophage activation is that it does not result in increased body temperatures (i.e. fever) as has been reported with many non-specific stimulants of those defenses. This critical advantage of neutral soluble glucan may lie in the natural profile of responses it mediates in white blood cells. It has been shown that the neutral soluble β-glucan of the present invention selectively activates immune responses but does not directly stimulate or prime cytokine (e.g., IL-1 and TNF) release from mononuclear cells, thus distinguishing the present neutral soluble glucan from other glucan preparations (e.g., lentinan, kresein) and immunostimulants.
[0043] In addition, it has been-demonstrated herein that the neutral soluble glucan preparation of the present invention possesses an unexpected platelet stimulating property. Although it was known that glucans have the ability to stimulate white blood cell hematopoiesis, the disclosed platelet stimulating property had not been reported or anticipated. This property can be exploited in a therapeutic regimen for use as an adjuvant in parallel with radiation or chemotherapy treatment. Radiation and chemotherapy are known to result in neutropenia (reduced polymorphonuclear (PMN) leukocyte cell count) and thrombocytopenia (reduced platelet count). At present, these conditions are treated by the administration of colony-stimulating factors such as GM-CSF and granulocyte colony-stimulating factor (G-CSF). Such factors are effective in overcoming neutropenia, but fail to impact upon thrombocytopenia. Thus, the platelet stimulating property of the neutral soluble glucan preparation of this invention can be used, for example, as a therapeutic agent to prevent or minimize the development of thrombocytopenia which limits the dose of the radiation or chemotherapeutic agent which is used to treat cancer.
[0044] The invention is further illustrated by the following Examples.
EXAMPLES
Example 1: Preparation Of Neutral Soluble Glucan From S. Cerevisiae
[0045] [0045] Saccharomyces cerevisiae strain R4 Ad (a non-recombinant derivative of wild-type strain A364A), was grown in a large-scale fermentation culture using a defined glucose, ammonium sulfate minimal medium. The production culture was maintained under glucose limitation in a feed-batch-mode (New Brunswick MPP80). When the growing culture reached late logarithmic phase, the fermentation was ended and the β-glucan was stabilized by adjusting the culture to pH 12±0.5 using 10 M NaOH. The yeast cells containing β-glucan were harvested by continuous-flow centrifugation (Westfalia SA-1). After centrifugation, the cells were collected into a stainless steel extraction vessel.
[0046] The first step in the extraction process was an alkaline extraction accomplished by mixing the cells with 1 M sodium hydroxide (NaOH) at 90±5° C. for 1 hour. Upon completion of this alkaline extraction, the β-glucan remained in the solid phase, which was collected by continuous centrifugation (Westfalia SA-1). The collected cell wall fraction was extracted a second time using the same procedure and under the same conditions. Treatment with alkali hydrolyzed and solubilized the cellular proteins, nucleic acids, mannans, soluble glucans and polar lipids into the supernatant fraction, and deacety-lated chitin to chitosan in the cell wall.
[0047] The second step in the extraction process was a pH 4.5±10.05 (adjusted with concentrated HCl) extraction at 75±0.5° C. for 1 hour. This was followed by a 0.1 M acetic acid extraction to complete the removal of glycogen, chitin, chitosan and remaining proteins. The solids were collected and rinsed twice with Purified Water USP to remove any residual acid as well as any yeast degradation products.
[0048] The third step in the extraction process was a set of six organic extractions. The first four extractions were carried out in isopropanol. The solids were collected by centrifugation and then subjected to two acetone extractions. The two-stage organic extractions eliminated nonpolar lipids and hydrophobic proteins which may have co-purified with the drug substance. The resulting wet solids were dried in a vacuum oven at 65±5° C. for 48-96 hours to yield a free-flowing powder.
[0049] At this stage the extraction process yielded a stable, insoluble intermediate consisting of approximately 90% β-glucan, called whole glucan particles (WGPs). The dry WGP intermediate was stored at 15-30° C. until further use.
[0050] The WGP powder was resuspended in 98% (w/v) formic acid, in a glass reaction vessel at room temperature. The resulting mixture was heated to 85±5° C. for 20 minutes. Under these conditions, the WGPs were partially hydrolyzed and solubilized to provide the desired molecular weight distribution of soluble β-glucan which was then precipitated by adding 1.5 volumes of ethanol. After complete mixing, the preparation was centrifuged to collect the β-glucan precipitate. Any residual formic acid was removed by boiling the β-glucan preparation in Purified Water USP for three hours.
[0051] Any unhydrolyzed WGPs were then removed from the β-glucan solution by centrifugation. The β-glucan solution was raised to pH 12.5±0.5 by the addition of the concentrated sodium hydroxide. The remaining purification steps were carried out by ultrafiltration.
[0052] The soluble alkaline β-glucan preparation was passed through a 100,000 nominal molecular weight (NMW) cut-off membrane ultrafilter (Amicon DC10). Under alkaline conditions this membrane ultrafilter removed insoluble and high. molecular weight soluble β-glucan. Trace low molecular weight degradation products were then removed by recirculation through a 10,000 NMW cut-off membrane ultrafilter. The ultrafiltration was conducted as a constant volume wash with 0.1 M NaOH.
[0053] The β-glucan solution was re-annealed under controlled conditions by adjusting the pH to 7.0±0.5 with concentrated hydrochloric acid, heating to 60±10° C., which was maintained for 20 minutes and then cooled. The neutral re-annealed solution was then concentrated and washed with Sodium Chloride Injection USP in a 70,000 NMW cut-off membrane ultrafilter (Filtron Minisep) to enrich for the re-annealed neutral soluble glucan. Next the material was filtered through a 300,000 NMW cut-off membrane ultrafilter (Filtron Minisep) to remove high molecular weight and aggregated glucan molecules. In the same ultrrafilter, the neutral soluble glucan material was washed with Sodium Chloride Injection USP in a constant volume wash mode.
[0054] The neutral soluble glucan was then concentrated in a 10,000 NMW cut-off membrane ultrafilter. The concentration process continued until a concentration of at least 1.0 mg/ml hexose equivalent was achieved.
[0055] The resulting neutral soluble glucan was then subjected to filtration through a depyrogenating filter (0.1 micron Posidyne) and a sterile 0.2 micron filter (Millipak) to yield sterile, pyrogen-free neutral soluble glucan. The neutral soluble glucan solution was stored at controlled room temperature (15-30° C.) until further use. The aqueous solubility of neutral soluble glucan in the pH range of 4 to 8 is approximately 100 mg/ml. The solubility increased with increasing pH and reached approx. 150 mg/ml at pH 13.
Example 2: Analysis Of Neutral Soluble Glucan
[0056] A. Glucose, Mannose and Glucosanine
[0057] Monosaccharide analysis was performed to quantitate the relative amounts of β-glucan (as glucose), mannan or phosphomannan (as mannose), and chitin (as N-acetyl glucosamine) in the neutral soluble glucan. The sample was hydrolyzed to monosaccharides in 2 M trifluoroacetic acid for 4 hours at 110° C., evaporated to dryness, and redissolved in water. Monosaccharides were separated on a Dionex HPLC system using a CarboPac PA100 column (4×250 mm) using 5 M NaOH at 1 ml/min and quantitated using a pulsed electrochemical detector (Dionex Model PED-1). The sensitivity of this assay for monosaccharides is 0.1% (w/w).
[0058] Glucose (retention time of 16.6 mm) was identified as the only monosaccharide component of neutral soluble glucan along with traces of glucose degradation products (from hydrolysis) anhydroglucose at 2.5 min and 5-hydroxymethylfurfural at 4.3 min. The results confirm that neutral soluble glucan consisted of ≧98% glucose.
[0059] B. FTIR
[0060] Fourier transform infrared spectroscopy by diffuse reflectance (FTIR, Matson Instruments, Polaris) of lyophilized neutral soluble glucan samples was used to determine the anomeric structure (α vs. β), and linkage type (β(1-3), β(1-6), β(1-4)) present in neutral soluble glucan. Absorption maxima of 890 cm −1 identified β(1-3) linkages; 920 cm −1 identified β(1-6) linkages. No presence of α-linked anomers (e.g., glycogen, 850 cm −1 ) or β(1-4)-linked polysaccharides (e.g., chitin, 930 cm −1 ) were detected.
Example 3: Conformational Analysis
[0061] A solution of β-glucan which was not processed by alkali dissociation and re-annealing was analyzed for its compositional identity by gel permeation chromatography (pH 7) and found to contain multiple species, referred to herein as high molecular weight aggregate (Ag), Peak A and Peak B (See FIG. 2). Neutral soluble glucan which was prepared by alkali dissociation and re-annealing as described in Example 1, is present as a single peak (see FIG. 3) with an average molecular weight of 92,660 daltons at pH 7. The distinct conformations of neutral soluble glucan and Peak B were demonstrated by gel permeation chromatography at pH 7 and pH 13 using a refractive index detector. Neutral soluble glucan underwent a significant conformational transition from pH 7 to pH 13 which illustrates complete dissociation of the multiple helix at pH 7 to a single helical form at pH 13 (see FIG. 3). In contrast, Peak B only underwent a slight shift in molecular weight from pH 7 to pH 13 (see FIG. 4). The molecular weight of neutral soluble glucan and Peak B glucans as a function of pH is shown below in Table 1.
TABLE 1 MW MW Ratio Sample pH 7 pH 13 (pH 7/pH 13) Neutral soluble 92,666 18,693 4.96 glucan Peak B 8,317 7,168 1.16
[0062] The conformation of neutral soluble glucan and Peak B glucan was also determined by aniline blue complexing (Evans et al., 1984, Carb. Pol., 4:215-230; Adachi et al., 1988, Carb. Res., 177: 91-100), using curdlan, a linear β(1-3) glucan, as the triple helix control and pustulan, a β(1-6) glucan, as a non-ordered conformational control. The results are discussed below and shown in Table 2.
[0063] The curdlan triple helix control complexed with aniline blue resulting in high fluorescence. Increasing the NaOH concentration began to dissociate the curdlan triple helix slightly, but NaOH concentrations >0.25 M are required for complete dissociation of curdlan. The pustulan non-ordered control only formed a weak complex with aniline blue resulting in low fluorescence measurements which were not affected by NaOH concentration.
[0064] The neutral soluble glucan complexed effectively with aniline blue at low NaOH concentration (25 mM NaOH) resulting in high fluorescence. However, the neutral soluble glucan conformation dissociated significantly (50%) at NaOH concentrations as low as 150 mM NaOH indicating that it exists as a unique conformation compared to naturally occurring β-glucans, such as laminarin and curdlan, which require significantly higher NaOH concentrations for dissociation to occur. Peak B formed a weak complex with aniline blue due to its single helical conformation.
TABLE 2 Conformational Analysis of Glucans by Aniline Blue Complexing Fluorescence 25 mM 100 mM 150 mM Test Material NaOH NaOH NaOH Blank 0 2 0 Curdlan 53.5 41.6 36 β(1-3) glucan Pustulan 9.8 8.3 8.0 β(1-6) glucan Neutral soluble glucan 40 25.6 20.2 Peak B 12.4 6.2 4.1
Example 4: Effects Of Neutral Soluble Glucan On Human Monocyte Production Of TNFα
[0065] Human peripheral blood mononuclear cells were isolated (Janusz et al., (1987), J. Immunol., 138: 3897-3901) from normal citrated and dextran-treated blood, washed in Hank's balanced salt solution (HBSS), lacking calcium, magnesium, and phenol red, and purified by gradient centrifugation on cushions of Ficoll-Paque (Pharmacia Fine Chemicals, Piscataway, N.J.). The mononuclear cells were collected into HBSS, washed twice, resuspended in RPMI 1640 Medium (Gibco, Grand Island, N.Y.) containing 1% heat-inactivated autologous serum (56° C. for 30 min.), and counted on the Coulter counter.
[0066] For the preparation of monocyte monolayers, 1 ml of 2.2×10 6 mononuclear cells/ml was plated into wells of 24-well tissue culture plates (Costar, Cambridge, Mass.), incubated for 1 hour at 37° C. in a humidified atmosphere of 5% CO 2 , and washed three times with RPMI to remove nonadherent cells. A second 1 ml aliquot of 2.2×10 6 mononuclear cells/ml was layered into each well and incubated for 2 hours described above before removal of the nonadherent cells. By visual enumeration at 40X with an inverted phase microscope and a calibrated reticle, the number of adherent calls for 30 different donors was 0.77±0.20×10 6 per well (mean±SD). By morphology and nonspecific esterase staining, >95% of the adherent cells were monocytes.
[0067] Monocyte monolayers were incubated at 37° C. in the CO 2 chamber for 0 to 8 hours with 0.5 ml of RPMI, 1% heat-inactivated autologous serum, 10 mM EPES, and 5 mM MgCl 2 in the absence and presence of various glucan preparations. The culture supernatant was removed, clarified by centrifugation at 14,000 g for 5 min at 4° C., and stored at −70° C. before assay of TNFα.
[0068] The concentration of TNFα in the monocyte supernatants was measured by an enzyme-linked immunoadsorbent assay (ELISA) with the BIORINE TNF Test kit (T Cell Sciences, Cambridge, Mass.), which had a lower limit of detectability of 40 pg/ml. The data are expressed as pg per 10 6 monocytes, which was calculated by dividing the quantity of cytokine in 0.5 ml of supernatant by the number of monocytes per well.
[0069] For the determination of cell-associated levels of TNFα, the adherent monocytes were lysed in 0.25 ml PBS by three rounds of freezing and thawing, the lysates were cleared of debris by centrifugation at 14,000 g for 5 min at 4° C., and the resulting supernatants were stored at −70° C. Newly prepared monocyte monolayers contained no detectable levels of intracellular TNFα.
[0070] The results are shown in Tables 3 and 4 below.
TABLE 3 TNFα Synthesis by Human Monocytes Stimulated with Various Glucan Preparations TNFα (pg/10 6 monocytes) Glucan Conc. 1 2 3 Mean ± SD Buffer Control 36 39 2 26 ± 21 Neutral soluble 1 mg/ml 44 51 33 43 ± 9 glucan Laminarin 1 mg/ml 372 324 227 308 ± 74 Whole 4 × 10 7 /ml 2129 1478 1683 1763 ± 333 Glucan particles
[0071] [0071] TABLE 4 TNFα Stimulation by Different Conformational Structures of Soluble β-Glucan TNFα Glucan Conc. (pg/10 6 monocytes) Buffer Control 1 mg/ml 40 Laminarin 1 mg/ml 1312 Neutral soluble glucan 1 mg/ml 16 Peak B 1 mg/ml 1341 Glucan Particles 4 ± 10 7 /ml 2065
[0072] Table 3 shows that TNFα was stimulated by insoluble glucan particles and by laminarin, a soluble β(1-6) and β(1-3) linked glucan. There was no stimulation of TNFα by neutral soluble glucan. Table 4 shows similar results, but further confirms that TNFα stimulation is dependent upon conformational structure. The neutral soluble glucan did not stimulate TNFα while Peak B (single helical conformation) did stimulate TNFα.
Example 5: Avidity Of Neutral Soluble Glucan For The Glucan Receptor
[0073] Monolayers of human monocytes, prepared on siliconized glass coverslips (Czop et al., 1978, J. Immunol., 120:1132), were incubated for 18 minutes at 37° C. in a humidified 5% CO 2 incubator with either 0.25 ml of buffer (RPMI-Mg-HEPES) or a range of concentrations (0.1-50 μg/ml) of neutral soluble glucan. The monocyte monolayers were then washed twice with 50 ml of RPMI 1640 medium and were layered with 0.25 ml of 4.8×10 6 /ml zymosan particles (Czop and Austen, 1985, J. Immunol., 134:2588-2593). After a 30 minute incubation at 37° C., the monolayers were washed three times with 50 ml of Hank's balanced salt solution to remove noningested zymosan particles. The monolayers were then fixed and stained with Giemsa. The ingestion of zymosan particles by at least 300 monocytes per monolayer was determined by visual observation under a 1000X light microscope.
[0074] Monocyte monolayers protreated with buffer, 50 or 500 μg/ml of neutral soluble glucan as described above were subsequently tested for their capacity to ingest IgG coated sheep erythrocytes (E′IgG). After an 18 minute preincubation with the neutral soluble glucan, the monolayers were incubated with 0.25 ml of 1×10 7 /ml E′IgG for 30 minutes at 37° C., washed three times with 50 ml of Hank's balanced salt solution, treated for 4 minutes with 0.84% NH 4 Cl to lyse noningested E′IgG, and fixed and stained as described above. The percentages of monocytes ingesting ≧1 and ≧3 E′IgG were determined by counting at least 300 monocytes per monolayer.
[0075] The percent inhibition of monocyte ingestion was determined by subtracting the percentage of monocytes ingesting targets after pretreatment with the neutral soluble glucan from the percentage ingesting targets after pretreatment with buffer, dividing this number by the percentage ingesting targets after pretreatment with buffer and multiplying by 100. The data are expressed as the mean of two experiments and are reported in Table 5.
TABLE 5 Glucan-receptor Binding Capacity of Distinct Conformations of Soluble β-glucans Test Material Conc. % Inhibition Buffer — 0% Neutral soluble glucan 50 μg/ml 74% 500 μg/ml 86% Peak B 50 μg/ml 50% 500 μg/ml 56%
[0076] Both β-glucan preparations tested above inhibited monocyte ingestion of zymosan particles demonstrating their capacity to competitively bind to the β-glucan receptor, on human monocytes. Neutral soluble glucan demonstrated a higher receptor binding capacity than Peak B as indicated by the greater level of inhibition achieved at both 50 μg/ml and 500 μg/ml. This biological assay demonstrates that the neutral soluble glucan is a superior ligand for the β-glucan receptor.
Example 6: Lack Of In Vitro Stimulation Of IL-1βAnd TNFα From Human Mononuclear Cells
[0077] Venous blood was obtained from healthy male volunteers and mononuclear cells were fractionated by Ficoll-Hypacue centrifugation. The mononuclear cells were washed, resuspended in endotoxin-free RPMI-1640 culture medium—ultrafiltered to remove endotoxins as described elsewhere (Dinarello et al., 1987, J. Clin. Microbiol. 25:1233-8)—at a concentration of 5×10 6 cells/ml and were aliquoted into 96-well microtiter plates (Endres et al., 1989, N. E. J. Med. 320:265-271). The cells were then incubated with either 1 ng/ml endotoxin (lipopolysaccharide, E. coli 055:B5, Sigma, St. Louis), or 10 to 1000 ng/ml βglucan, at 37° C. for 24 hours in 5% CO 2 and then lysed by three freeze-thaw cycles (Endres et al., 1989, N. E. J. Med. 320:265-271). Synthesis of IL-1β, and TNFα was determined by specific radioimmunoassays as described elsewhere (List et al., 1987, Lymph Res. 6:229-244; Lonnemann et al., 1988, Lymph. Res. 7:75-84; Van der Meer et al., 1988, J. Leukocyte Biol. 43:216-223.
[0078] To determine if neutral soluble glucan could act endotoxin, a known cytokine stimulant, mononuclear cells were pre-incubated- with 1, 10, and 1000 ng/ml of the neutral soluble glucan for 3 hours at 37° C. in 5% CO 2 . The cells were washed to remove neutral soluble glucan and were then incubated with 1 ng/ml endotoxin as described above. IL-1β and TNFα were determined as described above.
[0079] The results are summarized in Table 6. Neutral soluble glucan used as a stimulant at doses of 10-1000 ng/ml alone did not induce increased levels of IL-1β or TNFα synthesis over the control buffer treated cells. Endotoxin LPS, a known stimulant, resulted in significantly increased levels of both cytokines. In a second phase of this experiment neutral soluble glucan was tested for its ability to act as a priming agent for mononuclear cell cytokine synthesis. The cells from the same donors were pre-incubated with three doses of neutral soluble glucan (10-1000 ng/ml) and were then exposed to endotoxin as a co-stimulant. Neutral soluble glucan did not result in any amplification of the IL-1β and TNFα levels compared to endotoxin alone.
TABLE 6 In Vitro IL-1β and TNFα Synthesis by Human Peripheral Blood Mononuclear Cells IL-1β TNFα Stimulant (ng/ml) 1 (ng/ml) 1 Cells only <0.10 0.14 Neutral 10 ng/ml 0.13 0.16 soluble 100 ng/ml 0.12 0.16 glucan 1000 ng/ml <0.10 0.14 LPS 1 ng/ml 2.62 2.22 LPS (1 ng/ml) + 10 ng/ml 2.62 2.25 Neutral 100 ng/ml 2.57 2.07 soluble 1000 ng/ml 2.85 2.27 glucan
Example 7: In Vivo Protection Against Infection In Mice
[0080] A sepsis model was developed in rats to characterize the efficacy of β-glucan in protecting an immunologically intact host against serious infections, such as those which commonly occur following abdominal.. surgery. The rat model for intra-abdominal sepsis has been well described in the scientific literature (Onderdonk et al., 1974, Infect. Imun., 10:1256-1259).
[0081] Groups of rats received neutral soluble glucan (100 μg/0.2 ml) or saline control (0.2 ml) intramuscularly 24 hours and 4 hours prior to infectious challenge. A defined polymicrobic infectious challenge (cecal inoculum) was placed into a gelatin capsule which was then surgically implanted into the peritoneal cavity of anesthetized rats through an anterior midline incision. The early peritonitis from this experimentally induced infection was associated with the presence of gram-negative organisms within the blood and peritoneal cavity culminating in mortality. The cecal inoculum contained an array of facultative species, such E. coli, as well as other obligate anaerobes ( Streptococcus sp., Bacteroides sp., Clostridium perfringens, Clostridium ramosum, Peptostretococus racrus and broductus, Proteus mirabilis ). The animals were observed four times per day for the first 48 h and twice per day thereafter. The results are reported in Table 7.
TABLE 7 Effect of Neutral Soluble Glucan on Mortality in a Rat Model for Intra-abdominal Sepsis Group Mortality (%) P vs. Saline Saline 12/20 (60) Neutral soluble glucan 2/10 (10) <0.01
[0082] These results demonstrate that neutral soluble glucan which does not induce IL-1β and TNFα protects mice from lethal bacterial challenge.
Example 8: Demonstration Of Safety For Human Administration
[0083] A randomized, double-blind, placebo-controlled clinical trial was conducted on healthy males to evaluate the safety of neutral soluble glucan (2.25 mg/kg) injected by intravenous infusion compared to a placebo control. No adverse effects were observed. There was also no observed elevation in IL-1, TNF, IL-6, IL-8 and GM-CSF. Single intravenous administration of neutral soluble glucan resulted in an increase in monocytes and neutrophils and in the killing activity of these cells proving that neutral soluble glucan retains the desirable immunological activities in humans. See Tables 8, 9-and 10 below. However, as shown in FIGS. 5 and 6 no changes occurred in serum IL-1 and TNF and none of the patients experienced fever or inflammatory reactions. The results are consistent with the in vitro data reported in the earlier examples.
TABLE 8 Change In Absolute Neutrophil Counts (× 1000/μl) After Neutral Soluble Glucan Administration Dose Level B Hour 8 Hour 12 Hour 24 Saline Mean 4.06 4.34 4.31 3.43 SD 2.12 1.53 1.16 1.46 N 6 6 6 6 2.5 mg/kg Mean 4.11 11.29* 8.18 5.32 Neutral SD 1.15 4.39 3.80 1.75 Soluble N 6 6 6 6 Glucan
[0084] [0084] TABLE 9 Change in Monocyte Counts (× 1000/μl) After Soluble Neutral Glucan Administration Dose Level B Hour 8 Hour 12 Hour 24 Saline Mean 0.33 0.44 0.59 0.33 SD 0.09 0.10 0.22 0.12 N 6 6 6 6 2.5 mg/kg Mean 0.24 0.63* 0.67* 0.31 Neutral SD 0.10 0.24 0.32 0.15 Soluble N 6 6 6 6 Glucan
[0085] [0085] TABLE 10 Ex Vivo Microbicidal Activity of Normal Volunteers Receiving Neutral Soluble Glucan Mean Change in % Killing 1 Dose Level Hour 3 Hour 6 Hour 24 Day 2 Day 3 Day 6 Saline 0 0 0 0 0 0 2.5 mg/kg Mean 42.86 32.33 20.90 48.96 39.22 31.17 Neutral N 6 6 6 6 6 6 Soluble p-Value 0.062 0.036 0.300 0.045 0.085 0.026 Glucan
Example 9: Demonstration Of Efficacy In Vivo As Human Anti-Invective
[0086] In this clinical study, the safety, tolerance, and potential efficacy of the neutral soluble β-glucan was evaluated in patients undergoing major thoracoabdominal surgery with high risk of post-operative infection. Thirty-four males and females who underwent surgery received 0.5 mg/kg of the neutral soluble β-glucan . preparation or saline placebo, given as an intravenous infusion of 50 to 200 ml over one hour. Patients received multiple sequential doses of the neutral soluble β-glucan or placebo at 12 to 24 hours prior to surgery, 1 to 4 hours prior to surgery, 48 hours post-surgery, and 96 hours post-surgery.
[0087] Hospitalization, infections, and usage of anti-infective medications were examined as potential clinical efficacy parameters. Compared to patients given saline placebo infusions, patients who received the neutral soluble β-glucan spent an average of five fewer days in the hospital (12.3±6.1 days versus 17.3±15.5 days) and three fewer days in the Intensive Care Unit (0.1±0.4 versus 3.3±6.3 days; p<0.03, one-way analysis of variance).
[0088] The number of anti-infective medication prescriptions written per study day following surgery was consistently higher for control patients than for β-glucan recipient patients. Control patients were prescribed an average of three times the number of anti-infective medications as β-glucan recipients over the time period from surgery to discharge (p<0.005). During the Treatment and Post-Treatment Follow-up Phases, a total of 22 culture-confirmed infections in 5 control patients and 8 infections in 5 β-glucan recipient patients were identified (p<0.002).
[0089] Neutrophils (PMNs) and monocytes/macrophages (MOs) were purified from blood samples obtained at Baseline, Day 1, and Day 5 and examined for basal and phorbol myrisate acetate stimulated microbicidal activity against Staphylococcus aureus, Escherichia coli and Candida albicans. The neutral soluble β-glucan treatment generally increased the basal and phorbol-induced microbicidal activity of MOs and PENs.
Example 10: Wound Healing Effects Of Neutral Soluble Glucans
[0090] Wound healing studies were performed in a hairless mouse model having full thickness wounds with and without Staphylococcus aureus infection. Hairless SKH-1 inbred mice (6-8 weeks of age) were anesthetized with ether and a midline 3 cm full thickness longitudinal incision was made with a number 10 scalpel blade, producing a full thickness wound that did not penetrate the underlying fascia. Incisions were closed using steel clips placed at 1 cm intervals.
[0091] Formulations of neutral soluble glucan in phosphate buffered saline were applied 30 minutes following wounding and reapplied at 24 hour intervals during the seven day post-operative period. Two micrograms of neutral soluble glucan/mouse per day was topically applied. Wounds were examined daily and rank-ordered for effectiveness of formulation for enhancement of visual based wound healing. Wounds were scored for closure on a scale of 0-5, with 5 indicating the most healing. In one group of mice infected, the wound was treated with a culture of 10 7 Staphylococcus aureus 30 minutes after wounding and 2 hrs prior to treatment with the neutral soluble glucan formulation.
[0092] Histological evaluation of the wound site of each test group was made. The dermis of the control group (untreated wound) was heavily infiltrated with both lymphocytes and monocytes/macrophages. However, re-epithelialization that occurred at the epidermal layer was incomplete. The tissue section showed that the dermal tissue was weak, in that the tissue integrity was not maintained when it was sectioned.
[0093] The histology of the wounded tissue isolated from mice treated for three days with phosphate buffered saline containing the neutral soluble glucan showed that there was a heavy infiltration of macrophages and lymphocytes. Tissue integrity was good.
[0094] When topically applied to a wound, a composition of neutral soluble glucan stimulated white blood cell entry and activity at the wound site and accelerated wound healing within the dermal layer of the wound. Furthermore, the composition effectively eliminated infection produced by bacterial infection ( S. aureus ) and prevented the progression to sepsis. Untreated wounds progressed to sepsis.
Example 11: Stimulation Of Platelet Proliferation By Neutral Soluble Glucan
[0095] The platelet proliferation stimulatory effect of the neutral soluble glucan was tested in an animal model system following either irradiation or administration of the chemotherapeutic agent cisplatin. These experiments demonstrated the unexpected platelet stimulatory effect.
[0096] More specifically, saline or neutral soluble glucan prepared as described in Example 1 was administered to groups of 10 mice as a single IV bolus 20 hours prior to radiation exposure. Mice were bilaterally exposed to a total-body irradiation of 7.5-Gy. Fourteen days after irradiation the mice were sacrificed and whole blood samples were analyzed for peripheral blood counts. As shown in FIG. 7, the platelet cell count from neutral soluble glucan-treated mice was increased nearly 3-fold relative to saline-treated control levels.
[0097] In addition to tests on irradiated mice, cisplatin-treated mice were also tested for the effect of the neutral soluble glucan on platelet hematopoiesis. Balbic mice were injected intravenously with cisplatin at a dose of 9.3 mg/kg through the tail vein one hour before injecting either saline or the neutral soluble glucan, prepared as described in Example 1, intramuscularly in a single dose of 0 (saline) or 2 mg/kg on Day 0. Platelet counts were determined before treatment (Day 0) and at 2, 4, 6, 8, and 10 days post-treatment. The results of this experiment are shown in FIG. 8. Each data point represents the mean and standard error of platelet counts from five mice. The statistically significant differences (p<0.05) between the saline and neutral soluble glucan (2 mg/kg) are noted.
[0098] Biolocical DePosit
[0099] [0099] Saccharomyces cerevisiae strain R4 Ad was deposited on Aug. 20, 1992 with the American Type Culture Collection (ATCC), 12301 Parklawn Drive, Rockville, Md., under the terms of the Budapest Treaty. The strain has been assigned ATCC accession number 74181. Upon issuance of a patent, this deposit will be irrevocable.
[0100] Equivalents
[0101] Those skilled in the art will recognize or be able to ascertain, using no more than routine experimentation, many equivalents to the specific materials and components described herein. Such equivalents are intended to be encompassed in the scope of the following claims: | The present invention relates to neutral, aqueous soluble β-glucans which exert potent and specific immunological effects without stimulating the production of certain cytokines, to preparations containing the novel β-glucans, and to a novel manufacturing process therefor. The neutral, aqueous soluble β-glucan preparation has a high affinity for the β-glucan receptor of human monocytes and retains two primary biological (or immunological) activities, (1) the enhancement of microbicidal activity of phagocytic cells, and (2) monocyte, neutrophil and platelet hemopoietic activity. Unlike soluble glucans described in the prior art, the neutral, aqueous soluble β-glucan of this invention neither induces nor primes IL-1β, and TNFα production in vitro and in vivo. Safe and efficacious preparations of neutral, aqueous soluble β-glucan of the present invention can be used in therapeutic and/or prophylactic treatment regimens of humans and animals to enhance their immune response, without stimulating the production of certain biochemical mediators (e.g., IL-1β, TNFα) that can cause detrimental side effects, such as fever and inflammation. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to offshore drilling and well activities preformed from a floating drilling or workover rig or vessel.
2. Description of the Related Art
Today, when an offshore sub-sea well is intervened (work performed inside the production tubing below a sub-sea x-mas tree) from a floating vessel, a high pressure workover riser system is used. Such work-over riser systems has been designed with a subsea shut off valve (LRP) and/or a BOP configuration, close to the seabed and includes a riser disconnect package (RDP), to allow for a riser disconnect close to seabed when situations call for it. On the surface, the high pressure riser is terminated in a surface test tree (series of valves) above the rigfloor. To allow for riser tension, the drilling rig's main blocks for lowering and hoisting drillpipe is used to pull tension on the workover riser. Above the surface test tree, the pressure control equipment (surface BOP) for the well operations is installed, for lubricating into the well all of the work-over tools used in the operation.
Presently such systems are either designed for use in open water (stand alone), or the workover riser is run inside a 21″ OD low pressure marine drilling riser system, which includes a 18 3/″ inside diameter subsea drilling BOP installed on top of the sub-sea x-mas tree at seabed.
If the work-over system is being used inside a 21″ drilling riser, the lower shutoff valves in the workover riser system close to seabed, are controlled independent of the drilling BOP on the outside and carry independent equipment for service of the well. To run all of this equipment is very time consuming, in that the rig crew first has to run the 21″ marine drilling riser and the 18¾″ drilling BOP and suspend this system in the drilling rig's riser tension system underneath the rig floor. Then the rig crew has to run the workover riser system inside the marine drilling riser all the way to seabed and suspend this riser to the outer drilling subsea BOP in the lower end and suspend this riser system in the rig's main drilling hook by help of an elevator or lifting frame in the upper end. In doing so, the main travelling blocks/hook is occupied and will prevent the rig from being able to run jointed pipe into the workover riser.
If the high pressure riser is run as a stand alone system in open waters, the subsea blowout preventer (BOP) and the riser disconnect package (RDP) is installed on top of the subsea x-mas tree. This riser system is to date not intended for use with jointed drillpipe but intended for extending the production tubing up to the drilling rig's work deck or rigfloor, so that wireline and coil tubing can be run into the well. This riser system is then hung off in the rig's drilling riser tensioning system and/or in the drilling hook with the help of an elevator or lifting frame. The surface BOP's for the workover riser system is then installed above the rig floor and above the elevator to the rigs main hoisting system. This will also prevent the rig from being able to run jointed drillpipe into the well, since the equipment for running jointed pipe is occupied holding tension in the riser system. Hence with prior art, it is not possible to change from running wireline or coiled tubing equipment into the well, into the process of running jointed drillpipe into the well or vice versa, without having to change out the whole riser system or disconnecting the riser from the production sub-sea x-mas tree.
U.S. Pat. No. 5,676,209 describes a low pressure drilling riser system which comprises 2 BOP stacks. The upper BOP stack is submerged below the wave affected area closer to sea level and the lower BOP placed at seabed. A marine drilling riser extending back to the drilling installation can be disconnected from the upper BOP stack so that the riser will be free standing in the ocean due to air-cans or flotation elements installed below and adjacent to the upper BOP. This riser system is fundamentally different from the high pressure drilling and workover riser specified in the present invention in that the riser specified in U.S. Pat. No. 5,676,209 is a low pressure riser with high pressure kill and choke lines running outside and parallel to the main drilling riser bore. This riser would not be able to tolerate high pressures from the well. In order to perform workover operations, a complete new workover riser would have to be installed inside this riser and extending down to the subsea BOP. Hence this prior art would not introduce any added benefits to the invention here described.
PCT publication WO98/58152 describes an apparatus and method for drilling sub sea wells. This apparatus has no BOP at seabed and describe an apparatus where the BOP stack is moved to higher location closer to the sea level. The system introduces large buoyancy elements or air cans which is required if the drilling riser connecting the BOP to the drilling rig has to be disconnected. A system of this nature as described in the publication, could not be connected to a sub-sea production x-mas tree and hence the production tubing for underbalanced workovers. Hence, this prior art is fundamentally different from this invention.
The Norwegian patents NO 306174 (H. Møksvold) and NO 305138 (S. Gleditsch) describes a high pressure drilling and workover riser which resembles the riser described in this invention. NO 305138 and NO 316174 describe a system where the workover coil tubing BOPs are integrated with the upper BOP which is terminated in the drilling and workover riser in the upper end. However in order to effectively be able to change between drilling with jointed drillpipe and underbalanced work with standard workover BOP equipment on a conventional drilling rig, with minimum of time used and without modifications, it will be necessary to introduce the high pressure riser extension sleeve described in this invention. The high pressure riser extension would allow for the coil tubing or wireline BOPs to be introduced only when needed and the integration process can be performed without having to disconnect the main workover riser from the sub-sea wellhead or sub-sea x-mas tree. These inventions wills hence save expensive rig time and/or prevent expensive equipment from being rigged up on top of the riser in the upper BOP when not needed.
The PCT WO 03/067023 A1 describe an arrangement and method for well completion and intervention operations where a workover riser projecting from a wellhead and up to a vessel is used, and where the upper portion of the workover riser is designed to be displaced from the upper position to a lowered position favourable for rigging work, where at least the upper displaceable portion of the workover riser essentially follows the heave motion of the vessel. This is a telescopic high pressure joint integrated with the main workover riser which is high pressure only when fully stroked out and put in tension by the rigs main hoisting equipment. This prior art is run inside a conventional drilling riser and extends all the way down to the seabed. In order to convert to drilling the whole workover riser including the sub-sea safety valves and control system for same, must be disconnected from seabed and pulled out of the well. In deeper waters this will take considerable amount of time. However integrating this prior art in the high pressure extension sleeve in this invention would allow for more easy rig-up of workover BOPs and tools on the drill floor. Time savings are hence only achieved by combining prior art with this new invention in this particular way and combination.
SUMMARY OF THE INVENTION
A specific embodiment of the invention, and variations thereof, will now be described by way of example with reference to the accompanying drawings.
The present invention specify the use of a high pressure workover and drilling riser with two BOP stacks (sub-sea and near surface), where the upper BOP ( 20 ) is placed below the rig floor ( 90 ) and is interfacing a conventional low pressure drilling riser ( 30 ) and/or slip joint ( 40 ) ( 41 ) as seen in FIG. 1 . This figure also includes 1 conventional marine drilling riser ( 30 ) below the slip joint and where the whole riser system is being suspended by the rig's riser tensioning system ( 45 ), for placement of the upper BOP ( 20 ) below the wave affected zone near sea level. The purpose for this arrangement is to be able to drill with jointed drillpipe under more harsh weather conditions where rig heave need to be considered for the operation.
This invention specify the introduction of a short high pressure riser sleeve system ( 60 ) which is integrating the upper BOP ( 20 ) (inside the low pressure drilling slip joint ( 40 ) ( 41 ), which in combination with the high pressure riser system ( 10 ) described above, will make the change from running jointed drillpipe to allowing underbalanced operations with spooled equipment more effective and swift. Hence the high pressure riser sleeve can be run from the rig floor ( 90 ) down to the high pressure interface ( 25 in FIG. 3 ) above the upper BOP, thereby creating a HP conduit to the well. FIG. 3 describe the upper BOP ( 20 ) and how it integrates to the low pressure drilling riser ( 30 ) with high pressure chokelines ( 50 ) and killine ( 51 ) with the high pressure riser integration joint ( 60 ) inside and to the top of the high pressure riser ( 10 ) with a easy make up connector ( 21 ) to the high pressure riser ( 10 ). A system providing this option is novel art and has never been performed.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be described in connection with the attached drawings, in which:
FIG. 1 is a simplified and partial elevation view of one leg of a semisubmersible drilling platform connected via a telescopic low pressure drilling riser to a subsurface BOP on top of a high pressure riser, with a high pressure sleeve according to the invention inserted through the telescopic low pressure drilling riser.
FIG. 2 illustrates three elevation views of a telescoping low pressure drilling riser connected to an upper BOP stack on a high pressure riser suspended from the drilling platform. The three elevation views illustrate different extensions of the telescoping low pressure drilling riser.
FIG. 3 illustrates in elevation view the upper portion of two high pressure risers and, in partial elevation and horizontal section view, alternative embodiments upper BOP stacks arranged on top of the high pressure risers and connected to the lower portions of low pressure drilling risers, and corresponding lower portions of high pressure sleeves for being threaded down into said low pressure drilling risers and locked into said upper BOP stacks.
FIG. 4 is an elevation view of an upper portion of a high pressure sleeve according to the invention, and a partial elevation view, partial section view, of the lower portion of said high pressure sleeve.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
A system has been developed where the high pressure riser system carries one sub sea BOP stack including a riser disconnect package (RDP) directly above the sub sea BOP stack (not shown on the figure) with a high pressure riser ( 10 ) running back to surface, underneath the rigfloor ( 90 ). The high pressure riser is terminated in a surface BOP stack ( 20 ) above sea level ( 92 )) at cellar deck level ( 91 ) which may require a special a special slip joint ( 80 ) in FIG. 2 or a sub surface BOP stack just below sea level ( 92 ) in FIG. 1 . The differences between the surface BOP and the sub surface BOP is caused by the metocean conditions in the geographical areas where the rig is to be operated. The sub surface BOP stack ( 20 ) is arranged so that a normal low pressure drilling riser ( 30 ) is connected to the sub surface BOP stack ( 20 ) and the high pressure riser system ( 10 ). The position of the sub surface BOP stack is below Sea Level, and the purpose is to use the low pressure drilling riser with a large range/stroke slip joint ( 40 ) ( 41 ) to allow for more rig movements than a dry surface BOP stack where the heave limitation is dictated by the length of the low pressure telescopic section ( 80 ) which may be a special design above the surface BOP stack. This will prevent the upper BOP to be placed in the splash zone and hence be unaffected by waves in bad weather.
The system specified in this invention includes both options of sub surface BOP stacks ( FIG. 1 ) and surface BOP stacks in dry air ( FIG. 2 ). Both these systems will need the high pressure riser sleeve ( 60 in FIG. 1 ) and described in detail in FIG. 4 , to establish a high pressure connection between the top BOP stack ( 20 ) (sub- or surface BOP stack) and the required BOP equipment for the under-balanced work over operation. This operation may include wire line equipment such as wire line BOPs, or contain coiled tubing equipment such as BOPs and injector head. The top section of the riser sleeve will cater for interface to such equipment. The FIG. 4 shows the termination of the high pressure riser sleeve in that it allows for main hook elevator ( 68 ) to interface the high pressure riser sleeve in order to carry the weight of the workover BOPs and suspension (carry the weight of) for the HP riser sleeve.
The top BOP (surface/subsurface stack) ( 20 ) will carry rams which will be conditioned for the different tool strings the operation will require which can be seen in detail in FIG. 2 . Further an annular BOP ( 23 ) and a rotating head ( 24 ) will be part of the BOP stack if required for the operation. The FIG. 2 explains a sub surface. BOP stack ( 20 ) carrying two ram type BOPs ( 22 ), one annular BOP ( 23 ) and one rotating head ( 24 ). The ram type BOP set up will require one set of blind rams to be used as shut off device similar to a lubricator valve to allow for quick bleed off for tool entry or removal from the high pressure riser system. This avoids well pressure back to the rig when working with the tool strings.
In addition an annular BOP is proposed in order to ensure a possibility for a secondary seal if the primary seals ( 61 ) in the bottom section of the sleeve should leak.
The system will have a separate high pressure sub-sea BOP (not shown) configuration onto the well head or the X-mas tree, with a high pressure connection to the production tubing or well. A high pressure riser ( 10 ) runs from the sub-sea BOP stack to the surface- or subsurface BOP stack ( 20 ) which forms the upper termination of the high pressure riser system ( 10 ).
In order to allow for the same heave limits as normal drilling risers of today with stroke of the telescopic riser joint ( 41 ) up to 65 ft. the subsurface BOP stack is suspended in a low pressure riser ( 30 ) including the telescopic joint ( 41 , 40 ) and interface to the rig. This means that the high pressure riser ( 10 ) and BOP system ( 20 ) can be interfaced to any drilling rig without any major modifications to this part of the rig.
In order to allow for high pressure intervention without killing the well, the high pressure riser section to the rig floor is introduced. For normal well intervention purposes this sleeve will be terminated in a surface test tree ( 63 FIG. 4 ) or similar X over section on top, allowing for interfacing to wire-line equipment, coiled tubing equipment or other equipment required for entering a well under pressure.
The high pressure riser sleeve shall have an interface to the sub surface BOP stack ( 25 ) through a pressure tight seal ( 61 ) with an easy operated locking system, which can be a threaded connection ( 61 ) or a locking system carrying a locking sleeve design either through segments or other type of profiles ( 65 ). The connection shall carry seals ( 61 ) ( 65 ) to ensure a proper sealing method throughout the period the sleeve is in use. The top section is terminated in a crossover section ( 63 ) where the high pressure riser sleeve is suspended in an elevator ( 68 ) connected ( 69 ) to the hoisting machinery (hook and travelling blocks) in the derrick or tower. When the well is killed or in balance, the sleeve can be disconnected and removed to allow for direct access to the well through the rotary table with jointed pipe.
The purpose of using a high pressure riser sleeve like the one specified in this invention is to allow for high pressure access to the well from the drill floor ( 90 ).
The use of a sub surface BOP stack or a surface BOP ( 20 ) would only allow for high pressure integrity to the top of the upper BOP ( 20 ). By adding this high pressure riser sleeve ( 60 ), the high pressure system is extended up onto and above the drill floor ( 90 ).
The total length of the sleeve depends on the location of the upper BOP ( 20 ). If a surface BOP is used the low pressure riser section above the BOPs is short ( 80 ), if a sub surface BOP stack is used, the sleeve needs to comply with the distance from top of the high pressure BOP and up to drill floor.
Present technology and prior art would require a new riser system to be used or the high pressure riser sleeve would have to be run all the way down to the x-mas tree on seabed. Hence it is the combination of using a high pressure drilling riser with sub-sea and surface BOP and the high pressure sleeve which give the wanted effect.
Detail Description of Interface Between High Pressure Sleeve and HP Riser
Reference is made to FIG. 4 . The high pressure sleeve consists of a bottom section ( 61 ) or ( 65 ) which interfaces the top of the sub surface BOP stack ( 25 ). The connection shall carry seals in order to seal off between the sleeve and the high pressure section of the upper BOP ( 20 ) to prevent well fluid to leak off into the low pressure riser system. In addition, the bottom section shall be locked down in order to keep the sleeve in a stationary position, independent of well pressure and pull performed by the top tension (elevators and main drilling hook).
The interface ( 25 ) to lock down the bottom section to the upper BOP stack ( 20 ) may be a threaded connection ( 61 ), “J” slot interface system or a latch mechanism ( 65 ), all performing the lock down function that is required. The FIG. 3 shows a threaded interface ( 61 ) and a latch type interface ( 25 ).
The seals described shall have the ability to seal off the between the bottom section and the top of the upper BOP. The sealing arrangement shall comply with the same pressure rating as the upper BOPs.
In addition or in stead of using the said seals, the bottom section can carry a sleeve below ( 62 ) that which can interfaces the sub surface BOPs ( 20 ). The shown sleeve extension in FIG. 3 ( 62 ) will interface the annular preventer ( 23 ) or the ram type BOP ( 22 ), which allows for the sealing capability as listed above or form a secondary seal in addition to the seals explained above.
The top interface of the bottom section ( 61 ) ( 65 ) shall interface the tube or sleeve running back to the drill floor ( 90 ) through the rotary table. This part consist of high pressure tubing ( 60 ) in compliance to tools run in the well and at the same time keep the pressure integrity as required for the well or having the same pressure rating as the upper BOP ( 20 ).
The top termination of the sleeve shall interface the surface test tree ( 63 ) or similar equipment as the X-over section to where the wire line BOPs or coiled tubing BOPs interface will be established ( 64 ). As an example, a simplified surface test tree ( 63 ) is shown with the elevator ( 68 ) interface to carry the suspension of the sleeve and the wire line BOPs or the coiled tubing equipment required for a well intervention.
To ease the installation operation of the tool strings etc. into the sleeve or well, a telescope section can be a part of the high pressure sleeve section. Such a telescopic section can be arranged so that it forms a part of the sleeve. Such telescopic system is prior art and is described in PCT WO 03/067023 A1. The purpose will be to collapse the section, when running tools in or out of the sleeve in order to avoid moving parts caused by rig movement while carrying out this operation. When in operation the telescope will need to follow the riser part in case any shut in of the well is required. This telescope is not shown in any of the drawings. | An arrangement and method for integrating a high pressure riser sleeve from the upper end of a high pressure drilling and workover riser terminated by an upper BOP close to sea level in one end and by a sub-sea blowout preventer BOP or a low riser package LRP close to the seabed in the lower end. The high pressure riser sleeve being installed, connected and integrated to the high pressure drilling and workover riser and extending up to and above the drill floor, inside a low pressure drilling riser slip joint which is connected to the drilling and workover riser. This relates to offshore drilling and well activities preformed from a floating drilling or workover rig or vessel. Operations can be switched from drilling with jointed drillpipe in a conventional manner, into performing underbalanced wireline and/or coiled tubing activities with full well pressure, much more effectively than with prior art. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to switchgear for the field of electrical power distribution, and more particularly to operation selectors to control the operation of an operating mechanism for a switch of the switchgear, e.g. closed, open and ground positions of the switch
2. Description of the Related Art
Various operating controls for switchgear are furnished to appropriately select, control, and sequence the position of one or more switches and the relationship between the operating position of the switch and an access door or control component. Controls which appropriately sequence opening and closing of a switch with the opened/closed status of an access door are commonly known as interlocks.
While the prior art arrangements may be useful to provide operational controls and interlocks for various switchgear arrangements, the prior arrangements do not provide simple and effective operation selectors with blocking features for the operation of multiple position switches.
SUMMARY OF THE INVENTION
Accordingly, it is a principal object of the present invention to provide operation selectors for switchgear operating mechanism to prevent inadvertent operation directly between predetermined operating positions without first stopping at an intermediate operating position and performing an additional procedure.
It is another object of the present invention to provide an operation selector arrangement which includes an operation selector and features for blocking operation between some operational positions, the features for blocking operation having security capabilities separate from security capabilities on the operation selector such that the blocking features can remain secured while the operation selector can be rendered operational after removal of the security provisions.
It is a further object of the present invention to provide an operation selector with a blocking member such that operation is permitted between two adjacent operational positions while operation between non-adjacent operational positions is prevented.
These and other objects of the present invention are efficiently achieved by the provision of an operation selector arrangement for an operating mechanism that is controlled by movement of an operating shaft between the operational positions. Blocking features are provided for preventing operation between predetermined operational positions without first manipulating the blocking features. In a preferred arrangement, a an operating handle is utilized to operate the operation selector arrangement. A blocking member prevents operation of an operation selector between two operating positions without first stopping at an intermediate position, removing the operating handle, moving the blocking member, and then reinserting the handle. The blocking member is separately securable from the operation selector such that personnel may be authorized to operate the operation selector while other personnel are additionally authorized to manipulate the blocking member.
BRIEF DESCRIPTION OF THE DRAWING
The invention, both as to its organization and method of operation, together with further objects and advantages thereof, will best be understood by reference to the specification taken in conjunction with the accompanying drawing in which:
FIG. 1 is a top plan view of the operation selector arrangement of the present invention in a closed operational position;
FIG. 2 is a front elevational view of FIG. 1 partly in section and with parts cut away for clarity and with the operation selector in an open operational position;
FIG. 3 is a perspective view of the operation selector arrangement of FIGS. 1 and 2, and with the operation selector in an open operational position;
FIG. 4 is a top plan view of an operation selector disc of the operation selector arrangement of FIGS. 1-3;
FIG. 5 is a sectional view taken from the line 5--5 of FIG. 4;
FIG. 6 is a top plan view of a blocking member of the operation selector arrangement of FIGS. 1-3;
FIG. 7 is a left-side elevational view of the blocking member of FIG. 5;
FIG. 8 is a front elevational view of the blocking member of FIG. 6;
FIG. 9 is a partial front elevational view of an operating handle for operating the operation selector arrangement of FIGS. 1-8;
FIG. 10 is a bottom elevational view of the operating handle of FIG. 9;
FIG. 11 is a top plan view of a stop ring of the operation selector arrangement of FIGS. 1-3;
FIG. 12 is a front elevational view of the stop ring of FIG. 11; and
FIG. 13 is an elevational view, partly in section, of a specific embodiment of the operating handle of FIGS. 2, 3, 9 and 10.
DETAILED DESCRIPTION
Referring now to FIGS. 1-3, the operation selector arrangement 10 of the present invention controls the operational state of an operating shaft 12, which may also be characterized as an operating member, via the manual manipulation of an operating handle 14 (FIGS. 2, 3). For example, in one specific embodiment, the operating shaft 12 is rotatable with respect to a housing 16 between three operating positions to control an operating mechanism (not shown) of the type illustrated in U.S. Pat. Nos. 5,521,567 and 5,504,293 and co-pending application Ser. Nos. 08/653,176 filed on May 24, 1996 in the names of B. B. McGlone et al. and (attorney docket reference case SC-5270). In the illustrative example, the three operating positions correspond to the closed, open, and grounded operational states of a switch (not shown) driven by the operating mechanism, these operating positions being illustrated in FIGS. 1 and 3 by the corresponding indicia and referred to generally at 11, 13 and 15 respectively. In FIG. 1, the operation selector arrangement 10 is shown in the closed position as indicated by the pointer feature 17.
In accordance with important aspects of the present invention, the operation selector arrangement 10 prevents inadvertent operation directly between the closed and grounded positions, the operation selector arrangement 10 requiring that operation first be stopped in the open position and a predetermined action be taken before the operating handle 14 can be utilized to rotate the operating shaft 12 to the next position, as will be explained in more detail hereinafter. For example, in an illustrative example, the operating handle 14 can be utilized to rotate the operating shaft 12 directly between the closed (11) and open (13) positions and directly between the grounded (15) and open (13) positions. However, operation directly between the grounded (15) and closed (11) positions is not possible. The operation selector arrangement 10 requires that the operating handle 14 first be removed, a positive manipulation of components accomplished, and then the operating handle 14 reinserted before any operation is permitted to rotate the operating shaft 12 from the open to grounded or open to closed positions.
In a preferred arrangement, the operation selection arrangement 10 includes an operation selector disc 20, which may also be characterized as an operation selector member and which interfits with the operating handle 14 in a predetermined orientation, e.g. via a slot 24 in the operating selector disc 20 and a web 60 extending from the operating handle 14. A blocking member 30 (best seen in FIG. 3) limits the range of rotational movement of the operation selector disc 20 in combination with two end stops 40, 42 (FIG. 1). The blocking member 30 is movable so as to function in respective grounded and closed positions to block movement of the operating shaft 12 via the operating handle 14 into the respective grounded and closed operational positions. In FIGS. 1 and 3, the blocking member 30 is in the grounded position, thus blocking operation of the operating shaft 12 and the operation selector disc 20 into the grounded position. In FIG. 2, the blocking member 30 is shown in the closed position wherein it prevents rotation of the operating shaft 12 into the closed position. As shown in FIG. 3, the blocking member 30 includes a an extending tab portion 33 for the convenient grasping by the hand and movement of the blocking member 30.
In the closed position of FIG. 1, with the operating handle 14 inserted into the operation selector disc 20, the operating shaft 12 may be rotated into the open position as shown in FIGS. 2 and 3. However, if an attempt is made to move the operating handle from the open position of FIGS. 2 and 3 into the grounded position, the blocking member via a surface 31 (FIG. 3) prevents movement of the operating handle 14 and the operation selector disc 20. Thus, before the operating shaft 12 can be rotated into the grounded position, the operating handle 14 must be removed from the operation selector disc 20, the blocking member 30 moved from the grounded position into the closed position, and the operating handle 14 reinserted, whereupon the operating shaft 12 may now be rotated into the grounded position. In a specific embodiment as shown in FIG. 1, the blocking member 30 carries indicia at 39, for example, a double-ended arrow symbol, to provide visually perceptible indication to the user as to the location of the blocking member 30.
In accordance with additional features of the present invention, the operation selector arrangement 10 may be locked in the various operating positions, and further and independently, the blocking member 30 may be locked in either the grounded or closed position. For example, in the illustrative embodiment of FIGS. 1-3, the operation selector disc 20 includes holes 23, 25 and 29 which may be aligned in the various operational positions with a hole 53 in the stop ring 50. A shackle of a padlock or the like may be inserted through one of the aligned holes 23, 25, or 29 and the hole 53 referred to at 57 whereupon rotation of the operation selector disc 20 is prevented into other operational positions. Thus, when so locked, operation of the operation selector arrangement 10 between positions is prevented. For example, as shown in FIG. 1, placing a shackle of a lock at 57 through the holes 23 and 53 locks the operation selector arrangement 10 in the closed position. Additionally, the blocking member 30 includes a hole 35 that is aligned for cooperation with a hole 55 in the end stop 42 when the blocking member 30 is in the grounded position. Thus, placing a shackle of a lock or the like as referenced at 59 locks the blocking member 30 in the grounded position. Thus, until unlocked, the blocking member 30 can not be moved out of the grounded position and the operation selector arrangement may not be operated to rotate the operating shaft 12 into the grounded operational position, i.e. even though unlocked at 23, 53.
Turning now to a more detailed discussion of the structure and operation of the operation selector arrangement 10 and referring now additionally to FIGS. 4-10, the operation selector disc 20 (shown in more detail in FIGS. 4 and 5) extends over and is affixed to the operating shaft 12. The operation selector disc 20 and the operating handle 14 (shown in more detail in FIGS. 9 and 10) are arranged to interfit in a single predetermined relative orientation via the cooperation of the slot 24 of the operation selector disc 20 and the web 60 of the operating handle 14. The blocking member 30 (shown in more detail in FIGS. 6-8) is arranged below the operation selector disc 20 so as to freely pivot about the operation selector disc 20 and the operating shaft 12. The blocking member includes a central passage 37 for mounting thereof about the operating shaft 12. Rotation of the blocking member 30 is defined in a predetermined range by means of end point stops 40, 42, for example by means of a stop ring 50 (FIGS. 1-3) affixed to the housing 16 to establish the end stop points 40, 42. Specifically, the operation selector disc 20 includes a central hub portion 26 with a passage 27 to interfit with the operating shaft 12. The operation selector disc 20 also includes a rim 22 with an aperture slot 24 defined therethrough, which also extends through the central hub portion 26 of the operation selector disc 20 at 28. Further, the web portion 60 of the operating handle 14 protrudes from and extends below the circular hub 62 of the operating handle 14, the hub 62 also including a socket 64 to interfit with the cross-section of the operating shaft 12.
In the illustrative embodiment, the cross-section of the operating shaft 12 is a pentagon. so as to avoid use other than with authorized tools such as the operating handle 14. In one specific embodiment, the operating shaft 12 above the point referred to at 49 in FIG. 2 has a round (rather than pentagonal) cross-section smaller than the pentagonal cross-section of the lower portion of the operating shaft. In that specific embodiment, the operating shaft 12 is then driven through the operating selector disc 20 rather than directly via the operating handle 14. Thus, an operating handle 14 without the web 60 could not turn the operating shaft 12 separately from the operator selector disc 20. Additionally, in a specific embodiment, the operation selector disc 20 is affixed to the operating shaft 12 such that it is not easily removed, at least not with ordinary tools. For example, if a set screw 48 at threaded passage 47 is used to affix the operation selector disc 20 to the operating shaft 12, a non-standard driving head for the set screw 48 is utilized, such as a pentahead etc.
Referring now additionally to FIG. 13, a specific embodiment of the operating handle 14 includes a selective drive feature at the upper portion 70, such that the grasping portions 72, 74 of the upper portion 70 of the operating handle 14 may be rotated without rotation of the lower portion 76 of the operating handle 14. Specifically, the lower portion 76 includes a polygonal cross section which cooperates with the inside of a sleeve 78 having a like internal polygonal cross-section at 79 and a widened internal cross-section at the lower end 77. The upper portion 70 is slidably mounted with respect to the lower portion 76 and biased upwardly by a spring 80. Thus, the grasping portion 72, 74 may be rotated to a convenient position independent of the lower portion 76 of the operating handle 14, such that the grasping position may be conveniently adjusted without attempting to drive the operating shaft 12. After a comfortable position has been achieved, the user pushes down on the upper portion 70 whereupon the portion 77 engages the portion 76 so as to drive and rotate the lower portion 76 and the engaged operating shaft 12, as shown in FIGS. 2 and 3.
While there have been illustrated and described various embodiments of the present invention, it will be apparent that various changes and modifications will occur to those skilled in the art. Accordingly, it is intended in the appended claims to cover all such changes and modifications that fall within the true spirit and scope of the present invention. | An operation selector arrangement is provided for an operating mechanism that is controlled by movement of an operating shaft between the operational positions. Blocking features are provided for preventing operation between predetermined operational positions without first manipulating the blocking features. In a preferred arrangement, a an operating handle is utilized to operate the operation selector arrangement. A blocking member prevents operation of an operation selector between two operating positions without first stopping at an intermediate position, removing the operating handle, moving the blocking member, and then reinserting the handle. The blocking member is separately securable from the operation selector such that personnel may be authorized to operate the operation selector while other personnel are additionally authorized to manipulate the blocking member. | 7 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation of U.S. patent application Ser. No. 11/497,116 filed on Aug. 1, 2006, hereby incorporated herein by reference in its entirety.
TECHNICAL FIELD
[0002] The present invention relates to variable displacement compressors having an adjustable swash ring for changing the displacement of the compressor.
BACKGROUND OF THE INVENTION
[0003] Variable displacement compressors having a swash ring are well known in the art. Such compressors typically include a plurality of pistons that are driven by the swash ring. The swash ring is operatively coupled to a drive shaft and rotor assembly. The swash ring is angled or inclined relative to the rotor to change the total displacement of the compressor. One well known design includes a pivot pin that is fixed at one end to the drive shaft and pivotally connected to the swash ring at the other end.
[0004] Conventional swash ring compressors rely on a sphere to contact the inside of the swash ring supporting the load. Although this design works when the swash ring is made from a hard material, a swash ring made from soft alloys is preferred for improved seizure resistance. To allow a swash ring compressor to use a soft alloy for the swash ring, the load must be distributed over a larger area, which reduces the contact pressure.
[0005] While this design achieves its intended purpose many problems still exist. For example, because the pivot pin is located in the drive shaft, the drive shaft must be thicker or larger in diameter resulting in a higher design cost. Moreover, since the swash ring is limited by the pin thickness the compressor will have a large diameter but a poor volumetric efficiency. Further, prior art designs are unable to maintain a constant TDC without holding extremely tight positional tolerances. Further, inserting the pivot pin into the drive shaft at an angle requires expensive gauging. Since a single pivot pin carries the entire load, the pivot pin needs to be made of very expensive heat treated special steels. In addition, designs that include a single pin at a specified angle are not bidirectional thus, clockwise and anticlockwise models must be produced. This of course adds cost and manufacturing complexity. The design further has no provision for a counterweight balancing mass and lacks room for packaging such a mass to offset the pivot pin structure.
[0006] For these reasons and others a new and improved swash ring compressor is needed. Such a compressor is herein described below.
BRIEF SUMMARY OF THE INVENTION
[0007] In an aspect of the present invention, a variable displacement compressor is provided. The compressor includes a crankcase for receiving a fluid. The crankcase has a plurality of compression chambers in which the fluid is compressed. A plurality of pistons are disposed within the crankcase and configured for reciprocal movement within the plurality of chambers to compress and pump the fluid.
[0008] The compressor may further include a pivot pin projecting from the drive shaft with a sleeve disposed over the spherical end of the pivot pin. The sleeve being pivotably arranged about the spherical end of the pivot pin and slidably engaged within a swash ring. The compressor may further include a rotor assembly having a drive shaft and a rotor wherein the rotor has a first pivot arm support member extending from a first surface of the rotor; a sleeve slidably engaged to the drive shaft and configured for axial movement along a longitudinal axis of the drive shaft. The swash ring is coupled to the plurality of pistons and through rotary motion of the swash ring causes reciprocal motion of the plurality of pistons within the plurality of chambers, and wherein the swash ring is connected to the rotor by a first pivot arm pivotally connected to a swash ring at a first end and to the first pivot support member at a second end, and wherein the swash ring is pivotally mounted to the sleeve, whereby axial movement of the sleeve along the longitudinal axis of the drive shaft causes the swash ring to tilt relative to the rotor.
[0009] In yet another aspect of the present invention, the compressor includes a spring disposed around the drive shaft for biasing the swash ring away from the rotor.
[0010] In yet another aspect of the present invention, the compressor includes a counterweight member extending from the first surface of the rotor to counter balance the centrifugal forces created by the rotation of the swash ring.
[0011] In still another aspect of the present invention, the counterweight member extending from the first surface of the rotor is disposed opposite the pivot arm support member.
[0012] In still another aspect of the present invention, the counterweight member extending from the first surface of the rotor and is disposed inward of the swash ring.
[0013] In yet another aspect of the present invention, the compressor includes a thrust bearing to provide axial movement of the swash ring along the drive shaft toward the rotor.
[0014] In yet another aspect of the present invention, the compressor includes a swash ring stop member extending from the first surface of the rotor to prevent angular rotation of the swash ring past a predefined angle.
[0015] In still another aspect of the present invention, the first end of the first pivot arm is spherically shaped.
[0016] In still another aspect of the present invention, the second end of the first pivot arm is cylindrically shaped.
[0017] In yet another aspect of the present invention, the compressor includes an insert sleeve press fitted into a bore in the swash ring for receiving the first end of the first pivot arm.
[0018] In yet another aspect of the present invention, a variable displacement compressor is provided. The compressor includes a crankcase for receiving a fluid, wherein the crankcase has a plurality of compression chambers in which the fluid is compressed. Further, a plurality of pistons are disposed within the crankcase and configured for reciprocal movement within the plurality of chambers to compress and pump the fluid. A rotor assembly is further provided having a drive shaft and a rotor. The rotor has a pivot arm support member extending from a first surface of the rotor. A sleeve is slidably engaged to the drive shaft and configured for axial movement along a longitudinal axis of the drive shaft. A swash ring is coupled to the plurality of pistons and through rotary motion of the swash ring causes reciprocal motion of the plurality of pistons within the plurality of chambers. The swash ring is connected to the rotor by a pair of pivot arms pivotally connected to the swash ring at a first end and to the pivot support member at a second end. Further, the swash ring is pivotally mounted to the sleeve, whereby axial movement of the sleeve along the longitudinal axis of the drive shaft causes the swash ring to tilt relative to the rotor.
[0019] The compressor may further contain a rotor assembly having a drive shaft and a rotor, wherein the rotor has a first pivot arm support member extending from a first surface of the rotor; a sleeve slidably engaged to the drive shaft and configured for axial movement along a longitudinal axis of the drive shaft; and a swash ring coupled to the plurality of pistons and through rotary motion of the swash ring causes reciprocal motion of the plurality of pistons within the plurality of chambers. Wherein the swash ring is connected to the rotor by a first pivot arm pivotally connected to the swash ring at a first end and to the first pivot support member at a second end, and wherein the swash ring is pivotally mounted to the sleeve, whereby axial movement of the sleeve along the longitudinal axis of the drive shaft causes the swash ring to tilt relative to the rotor.
[0020] In yet another aspect of the present invention, the compressor includes a second pivot arm for connecting the swash ring to the rotor.
[0021] In yet another aspect of the present invention, the compressor includes a second pivot arm support member fixed to the rotor for supporting the second pivot arm.
[0022] In yet another aspect of the present invention, a variable displacement compressor is provided. The compressor includes a crankcase for receiving a fluid, wherein the crankcase has a plurality of compression chambers in which the fluid is compressed. Further, a plurality of pistons are disposed within the crankcase and configured for reciprocal movement within the plurality of chambers to compress and pump the fluid. A rotor assembly is further provided having a drive shaft and a rotor. The rotor has a pivot arm support member extending from a first surface of the rotor. A sleeve is slidably engaged to the drive shaft and configured for axial movement along a longitudinal axis of the drive shaft. A swash ring is coupled to the plurality of pistons and through rotary motion of the swash ring causes reciprocal motion of the plurality of pistons within the plurality of chambers. The swash ring is connected to the rotor by a pair of pivot arms pivotally connected to the swash ring at a first end and to the pivot support member at a second end. Further, the swash ring is pivotally mounted to the sleeve, whereby axial movement of the sleeve along the longitudinal axis of the drive shaft causes the swash ring to tilt relative to the rotor.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] FIG. 1 is a perspective view of a variable displacement swash ring type compressor, in accordance with an embodiment of the present invention;
[0024] FIG. 2 is a side perspective view of the swash ring and rotor assembly of the variable displacement compressor shown in FIG. 1 , wherein the swash ring is shown in a minimum displacement position, in accordance with an embodiment of the present invention;
[0025] FIG. 3 is a side perspective view of the swash ring and rotor assembly of the variable displacement compressor, wherein the swash ring is shown in a maximum displacement position, in accordance with an embodiment of the present invention;
[0026] FIG. 4 is a cross-sectional view through the swash ring and rotor assembly of the variable displacement compressor, wherein the swash ring is shown in a maximum displacement position, in accordance with an embodiment of the present invention;
[0027] FIG. 5 is a perspective view of the rotor of the rotor assembly, in accordance with an embodiment of the present invention;
[0028] FIG. 6 is a perspective view of a swash ring and the rotor assembly, in accordance with an embodiment of the present invention; and
[0029] FIG. 7 is a perspective view of an alternate embodiment of a rotor and swash ring, in accordance with the present invention;
[0030] FIG. 8 is a cross-sectional view of an alternate swash ring, in accordance with an alternate embodiment of the present invention;
[0031] FIG. 9 is a cross-sectional view of an alternate embodiment of a swash ring and rotor, in accordance with an alternate embodiment of the present invention;
[0032] FIG. 10 is a cross-sectional view of a sleeve that distributes the load on the swash ring, in accordance with an alternate embodiment of the present invention; and
[0033] FIG. 11 is a perspective view of the pin that supports the swash ring, in accordance with an alternate embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0034] Referring now to FIG. 1 a variable displacement compressor 10 is illustrated, in accordance with an embodiment of the present invention. Compressor 10 is referred to as a variable displacement compressor because the total displacement of the refrigerant pumping capacity may be adjusted by changing the inclination of a swash ring 11 , which will be described in further detail below. Variable displacement compressor 10 includes a crankcase 12 that has a plurality of chambers 14 configured to cooperate with a plurality of pistons 16 . Pistons 16 are operatively coupled to a swash ring 11 to cause reciprocal movement of pistons 16 within chambers 14 . Compressor 10 further includes a rotor assembly 20 having a rotor 22 rotationally fixed to a drive shaft 24 . Rotor assembly 20 imparts a rotational force to swash ring 11 to cause rotary movement of the swash ring. Typically, drive shaft 24 will have a pulley (not shown) mounted to one of its ends. A serpentine belt driven by an engine of an automotive vehicle engages the pulley and rotationally drives the pulley, although, the concepts of the present invention will be realized on a compressor where the drive shaft is driven by other means.
[0035] Referring to FIG. 2 , swash ring 11 and rotor assembly 20 are illustrated in further detail, in accordance with an embodiment of the present invention. Swash ring 11 is shown in a plane that is parallel with the base 36 of rotor 22 . When swash ring 11 is in the position shown in FIG. 2 , compressor 10 is at its minimum displacement. Rotor assembly 20 further includes a sleeve 26 . Sleeve 26 is operatively configured to slide axially along drive shaft 24 . Swash ring 11 is pivotably secured to sleeve 26 through a plurality of pivot pins 28 . While only one pivot pin 28 is illustrated, it should be understood that a similarly configured pivot pin (not shown) is disposed on the opposite side of drive shaft 24 . Pivot pins 28 are axially aligned with one another and extend radially outward from diametrically opposed sides of sleeve 26 . The pivot pins 28 pivotally engage the swash ring 11 to allow the swash ring to pivot about an axis running longitudinally through pivot pins 28 and through driveshaft 24 .
[0036] Further, swash ring 11 is pivotally mounted to rotor 22 to allow the swash ring to rotate relative to rotor 22 , as will be described in greater detail below. The angle of inclination of swash ring 11 relative to rotor 11 increases as sleeve 26 approaches rotor 22 . Swash ring 11 is biased away from rotor 22 by a biasing spring 30 disposed around drive shaft 24 . More specifically, spring 30 contacts rotor 22 at a first end 32 and sleeve 26 at a second end 34 . As sleeve 26 moves closer to rotor 22 spring 30 compresses. Conversely, as sleeve 26 moves away from rotor 22 spring 30 expands in length.
[0037] Referring now to FIG. 3 , a perspective view of swash ring 11 and rotor assembly 20 is illustrated, in accordance with an embodiment of the present invention. Swash ring 11 is shown in an inclined position relative to the rotor base 36 . The inclination of swash ring 11 is provided by the axial sliding movement of sleeve 26 along drive shaft 24 in a direction that compresses spring 30 .
[0038] Referring now to FIG. 4 , the attachment of swash ring 11 to rotor assembly 20 is further Illustrated in a cross-sectional view as indicated in FIG. 3 , in accordance with an embodiment of the present invention. Swash ring 11 is mounted to rotor 22 by a pair of pins 40 disposed adjacent on another (as shown in FIG. 5 ). Each pin 40 is secured or press fitted into bores 42 disposed in a pin support member 44 at a first end 46 of each pin 40 . Pin support member 44 is preferably integrally formed and extends from base 36 of rotor 22 . Each pin 40 is slidably and pivotably coupled to swash ring 11 at opposing ends 48 . More specifically, each opposing end 48 is preferably spherical and is fitted into a collar or guide bushing 50 having spherical sidewalls 52 that cooperatively mate with spherical surfaces of end 48 . Each collar bushing 50 is configured to slide within a bore 54 of swash ring 11 . In operation, as sleeve 26 slides away from rotor 22 causing swash ring 11 to move toward a plane that is parallel to base 36 of rotor 22 , as shown in FIG. 2 , swash ring 11 moves over each collar bushing 50 . In this manner, swash ring 11 is allowed to move between an inclined plane and a plane that is parallel with base 36 of rotor 22 .
[0039] Referring now to FIG. 5 , rotor 22 is illustrated in further detail, in accordance with an embodiment of the present invention. As previously stated, rotor 22 includes a pin support member 44 that extends from base 36 of rotor 22 . Support member 44 supports pins 40 at a predefined angle. While two support pins 40 are illustrated, the present invention contemplates the use of one pin as well as more than two pins to support swash ring 11 . Rotor 22 further includes a pair of sleeve stops 60 and 62 . Sleeve stops prevent further movement of sleeve 26 toward rotor 22 . When sleeve 26 is stopped by sleeve stops 60 and 62 , the variable displacement compressor is in a maximum displacement configuration. Rotor 22 further includes a counterweight structure 64 . Counterweight structure 64 is a mass of material (i.e., metal) that extends from the base 36 of rotor 22 . Counterweight 64 counters the centrifugal forces generated by the rotation of rotor 22 and the mass making up support pin structure 44 . Effectively, counterweight 64 balances out the centrifugal forces generated by the rotation of pin support structure 44 .
[0040] Referring now to FIG. 6 , a perspective view of swash ring 11 and rotor assembly 20 is shown, in accordance with an embodiment of the present invention. Swash ring 11 is at an inclination that causes the maximum displacement of refrigerant. At maximum displacement, sleeve stops 60 and 62 are shown in contact with an arm 70 integrally formed in and extending from sleeve 26 . This configuration allows sleeve 26 to move toward rotor 22 and compressing spring 30 until the surface 72 of arm 70 contacts sleeve stop 60 or 62 . Of course, the present invention contemplates the use of only one sleeve stop instead of two.
[0041] Referring now to FIG. 7 , a perspective view of an alternate embodiment of a rotor 100 and swash ring 102 are illustrated, in accordance with another embodiment of the present invention. As in rotor 22 described above, rotor 100 includes a pin support member 44 ′ that extends from base 36 ′ of rotor 100 . Support member 44 ′ supports a pair of pins 104 at a predefined angle. While two support pins 104 are illustrated, of course, the present invention contemplates the use of one pin as well as more than two pins to support swash ring 102 . Rotor 100 further includes a pair of sleeve stops 106 (one shown). Sleeve stops are configured and operate in the same manner as previously described with reference to rotor 22 shown in FIG. 5 , that is to prevent further movement of sleeve 26 (shown in FIG. 2 ) toward rotor 100 . Rotor 100 further includes a counterweight structure (not shown) having the same configuration as described and illustrated above with respect to rotor 22 (shown in FIG. 5 ).
[0042] With continuing reference to FIG. 7 , the attachment of swash ring 102 to rotor 100 will now be described. Swash ring 102 includes an elongated aperture 108 that extends through swash ring 102 . A tube bushing 110 is disposed in elongated aperture 108 . Elongated aperture 108 is configured such that the outer surfaces of tube bushing 110 contact the inside surface of aperture 108 and allows swash ring 102 to rotate relative to tube bushing 110 . Support pins 104 are substantially straight pins with a step 112 to prevent tube bushing 110 from sliding towards support member 44 ′. Further, support pins 104 include an annular groove 114 for lockably receiving a c-clamp 116 or similar device to secure tube bushing 110 to support pins 104 . This configuration provides an efficient means to rotatably attach the swash ring to the rotor.
[0043] Referring now to FIG. 8 , a cross-sectional view of an alternate swash ring 200 is illustrated in accordance with an alternate embodiment of the present invention. As shown in FIG. 8 , swash ring 200 includes a support sleeve 202 . Support sleeve 202 is press fitted into a bore 204 in swash ring 200 . A pin (not shown) similar to pin 40 having a spherical end 48 , as shown in FIG. 4 , is configured to support swash ring 200 around drive shaft 24 . In operation, the spherical end 48 of pin 40 slides along the inside surface of support sleeve 202 . A flared end 206 of bore 204 allows the swash ring to tilt with out interfering with pin 40 . Support sleeve 202 operates to distribute the load on pin 40 over a larger surface area of the swash ring 200 .
[0044] Referring now to FIG. 9 , a cross-sectional view of an alternate embodiment of a swash ring and rotor assembly generally referenced at 300 is shown. As in the above described embodiments, assembly 300 has a drive shaft 302 , a swash ring 304 and a rotor 306 . Swash ring 304 is supported around driveshaft 302 by a pin 308 . Pin 308 has a straight end 310 that is press fitted into a bore 312 in driveshaft 302 . Pin 308 also includes a spherical portion 314 opposite straight end 310 . Spherical portion 314 is disposed in a bore 316 disposed in swash ring 304 . Further, a sleeve 318 is provided that is press fitted into bore 316 . Sleeve 318 has mating surfaces 320 that have a similar shape and profile (i.e. spherical) as spherical portion 314 . Thus, in operation, swash ring 304 will pivot about spherical portion 314 changing its angle of inclination relative to the driveshaft 302 .
[0045] Referring now to FIGS. 10 and 11 , a cross-sectional view of sleeve 318 and a perspective view of pin 308 are shown. Sleeve 318 , as referenced above, Includes mating surfaces 320 that cooperate with spherical end 314 . Additionally, | A variable displacement compressor is disclosed. The compressor includes a crankcase for receiving a fluid. The crankcase has a plurality of compression chambers in which the fluid is compressed. A plurality of pistons disposed within the crankcase and are configured for reciprocal movement within the plurality of chambers to compress and pump the fluid. Further, a rotor assembly having a drive shaft and a rotor, wherein the rotor has a first pivot arm support member extending from a first surface of the rotor. A sleeve is slidably engaged with the drive shaft and configured for axial movement along a longitudinal axis of the drive shaft. A swash ring is coupled to the plurality of pistons and to the rotor by means of a pivot arm. Rotary motion of the swash ring and rotor causes reciprocal motion of the plurality of pistons within the plurality of chambers. | 5 |
This application is related to and claims priority from U.S. provisional patent application No. 60/147,681, filed on Aug. 6, 1999, which is hereby incorporated by reference in its entirety, including all claims, figures, and tables.
INTRODUCTION
The invention relates in part to analytical instruments providing cost effective, automated testing for low to medium sample volume applications. The invention also relates in part to components, features, disposables, reagent delivery systems, accessories, and methods for using such instruments. The analytical instruments of the invention may be used for analytical testing, and in particular, for automated medical diagnostic testing. The invention describes a completely self-contained test surface and reagent delivery device that is used in conjunction with the instrument of the invention to perform an automated sample analysis. The instrument and cartridge system are well suited to the medical point of care testing environment or other analytical testing environments.
BACKGROUND OF THE INVENTION
The following description of the background of the invention is provided simply as an aid in understanding the invention and is not admitted to describe or constitute prior art to the invention.
Conventional automated clinical and chemical analyzers tend to be large, complex, multi-module instruments. For example, U.S. Pat. No. 5,902,548 describes an analyzer for high-throughput analysis. Such analyzers can be expensive, difficult to maintain, and require a significant amount of floor or bench space. Sample-processing is generally handled independent of the analyzer and requires manual placement of the processed sample into the sampling position of the analyzer. Such analyzers are not cost effective for the analysis of low sample volumes nor for providing single test results.
Most conventional analyzers use a modular approach to the various assay functions required to complete an assay procedure. For instance, one module may deliver a test device to a section of the analyzer for sample application. The next module would be used to introduce one or more reagents. Another module may be required to incubate the test device and another one may be required to wash the test device prior to the next cycle of reagent additions. A final module would be used to analyze the result generated within or on the test device. Some devices, such as that disclosed in U.S. Pat. No. 6,042,786 integrate a keyboard as an on-board instrument component. As discussed in U.S. Pat. No. 5,332,549, separate module may be required to remove the spent test device from the analyzer. Such designs require precise placement of the test device to insure proper operation within the analyzer. At the same time, the analyzer conveyance system must allow the test device to be placed and removed without binding within the carrier position. U.S. Pat. Nos. 5,167,922 and 5,219,526 describe an arrangement of test device and carrier features within an analyzer that serve to lock the test device into a carrier. With these types of analyzers the entire test device must be rotated or conveyed to different processing stations.
Many automated analyzers use some form of aspirator in combination with a probe or pipet tip device to automatically draw and dispense a sample or reagent from one container to a test container. For example, U.S. Pat. No. 5,983,734 discloses an analyzer with an aspiration-type sample delivery device. Similarly, U.S. Pat. No. 6,063,340 discloses an analyzer with aspiration and dispensing probes for sample and reagent delivery. To avoid contamination, the tips often must be disposed of after each reagent addition or washed prior to contact with the next solution. Disposing of tips after each use adds a high disposable cost to the instrument. Continuous washing of a reagent delivery system means there is generation of a high volume of liquid biohazardous/toxic waste that must be routinely disposed of. Multiple samplings of a single reagent container increases the possibility that the reagent will become contaminated. If the tip contacts the solution, the sides of the tip or probe may be covered with solution (sample or reagent). The residual solution may then be inappropriately dispensed to the test container or to another reagent container. The contamination of the next reagent may lead to improper assay results not only in the first test being conducted but in all subsequent tests using that reagent container. The use of an aspiration type device means that the reagent containers are exposed to the open environment leading to evaporation issues and potential contamination. Fluctuations in the aspiration system can lead to significant contamination of the entire reagent delivery mechanism and to variable fluid volumes being dispensed. Most systems use multiple sample reagent containers and dispense a unit of reagent with the initiation of each new assay and contain a separate module that contains the actual test device or surface.
Many automated analyzers use centrifugal force for the movement and volume control of reagents. Use of centrifugal force requires a radial array of reagents and precise fluid path constructions. Centrifugal force is used to drive fluid over a barrier and into the next reagent or reaction chamber until a detection member is encountered. High precision molding requirements make individual rotary test devices extremely expensive. Multiple fluid paths and reaction chambers within the fluid path to introduce new reagents and allow incubation time make the design of test devices even more difficult. Subjecting the test device to multiple bursts of centrifugal force can introduce errors in the flow of fluids along the desired pathway. U.S. Pat. No. 5,912,134 discloses an assay cartridge using channels, capillaries, reservoirs, and stop junctions to control reagent delivery, and sample dilution within the cartridge as a function of capillary, gravitational, and centrifugal forces.
A few assay systems have used discrete reagent containers, such as ampules or capsules or bags. The reagents are released by a breaking or piercing mechanism. Reagent delivery is then based on a passive gravity feed and thus can not ensure that the complete volume of the required reagent is dispensed. The breaking or piercing mechanism may also interfere with reagent delivery. If the breaking or piercing mechanism is in contact with more than one reagent container it is possible that it can carryover a reagent that affects the next reagent delivered to the test surface. In some cases, once the piercing member has penetrated the reagent container the fluid flows through a channel within the piercing member to be delivered to the test surface by capillary action or gravity feed. For example, U.S. Pat. No. 5,968,453 describes a reagent cartridge that is open to a sampling device for removal of reagent. Conversely, U.S. Pat. No. 6,043,097 describes a complex reagent container consisting of a sealed lid, and a valve that controls opening and closing of one or more chambers in the container. The reagent chamber holds a glass ampule that is crushed to release reagent, and a filter element.
Other cartridges use a pierceable member to exclude sample from the test cartridge until the member is pierced and then deliver a specific amount of sample by capillary action to the test cartridge. U.S. Pat. Nos. 5,888,826 or 5,602,037 describes a device where downward displacement of a vacuum chuck is used to press down on one section of the test cartridge. Lowering the sample cup of the test cartridge lowers a piercing member into the pierceable member. When vacuum is applied an amount of sample may be aspirated into the sample cup.
U.S. Pat. No. 4,689,204 describes a reagent delivery system that utilizes a series of plunger-like cylinders of varying heights for reagent delivery. As an upper plate-like actuator is depressed onto the various cylinders a sample or reagent is delivered to a reaction tube. The reagent delivery sequence is controlled by the height of the cylinders. The shorter the cylinder the later in the sequence the reagent is delivered. The reaction tube contains a coarse filter between sample addition to the reaction tube and the final reagent delivery to the reaction tube. At the end of the reaction tube is a fine filter to retain the analyte of interest, particularly bacteria. A lens is included in the reaction tube pathway for visualization of the fine filter.
In another embodiment of U.S. Pat. No. 4,689,204, the individual reagent chambers may consist of a piston-like member that when pushed into the reagent chamber drives the reagent past a pressure sensitive seal into a delivery tube. An actuating member pushes the piston-like member that also pierces the seal at the exit port to initiate fluid flow.
In both embodiments of U.S. Pat. No. 4,689,204, sample and reagent flow through the reaction tube is capillary or gravity flow and the actuation of each reagent is based on the linear progression of the actuating member as it passes each piston-like member. Each fluid has only the time between contact of the actuator with it's specific piston-like member to the contact of the actuator with the next piston-like member to flow through the coarse filter and then the fine filter. The design of the coarse filter has a large open or dead volume or head space located above the coarse filter where premature mixing and interaction of the different fluids may occur. In addition this dead volume will retain a significant amount of fluid causing incomplete sample and reagent introduction to the fine filter.
U.S. Pat. No. 5,922,591 discloses an analytical device capable of collecting and analyzing a number of samples in a single unit. A pneumatic system is used to apply differential pressure for fluid movement.
Single use disposal diagnostic devices have been developed for a large number of applications, in particular for medical diagnostic applications. These tests provide timely single test results but require user intervention to produce the test results.
U.S. Pat. No. 5,006,309 describes a disposable device for use in an automated assay system. The device contains two wells. One well is used to process the sample and add reagents. The second well is used to read the assay result. The processed sample is transferred from one well to the other using jets of fluid. The processed sample consists of analyte and microparticles specifically reactive with the analyte. The processed sample is moved between wells without contacting a pipette or other transfer device. The sample well and the read well are connected by a fluid passage and processed sample is moved through the passage by a high velocity wash solution. The wash solution is introduced by a series of nozzles. The read well will retain a specific volume of the processed sample. The read well contains a fibrous matrix that will retain the processed sample. The flow of fluid through the fibrous matrix may be enhanced by the use of a vacuum or absorbent material under the matrix. The microparticle is used to specifically capture and retain the analyte. The fibrous matrix is selected to immobilize the microparticles within the fibrous matrix. Once the particles are immobilized a signal generating material is added to the matrix and the signal produced. The fibrous material must remain porous and support easy fluid flow once the microparticles are immobilized. Sample and reagents are added to the sample well through the use of pipettes and/or transfer devices that rely on aspiration mechanisms and are external to the disposable. Control of the wash solution speed is critical to effective functioning of the device.
Most assay devices or systems do not provide for on board processing of a sample collection device and even fewer systems can process more than one type of sample collection device or process more than one type of sample. U.S. Pat. No. 5,415,994 describes a manual assay device where the sample collection device is a swab. The specimen-containing swab is placed in a well within the assay device. Extraction reagents are added to the well containing the swab and allowed to flow past the swab extracting the analyte from the specimen on the swab. The solution continues to flow through the device to a test surface for analysis. The sample receiving position is joined to a bowl structure. The sample receiving position has a stop feature to properly position the swab above the bowl. The extraction chamber is in fluid contact with a sample receiving zone through an exit port. The matrix of the sample receiving zone defines the flow path from the extraction chamber. The extraction chamber is formed as an integral part of the solid device.
U.S. Pat. No. 5,084,245 describes a similar sample-processing device. The device is designed with a sample detection element in the base. The top of the device covers the sample detection element and contains an elongated feature positioned close to the sample detection element. This elongated feature is used to retain a swab carrying a sample. A number of extensions are contained within the elongated feature and used to squeeze or express fluid from the swab as it is pushed into the elongated feature. The expressed fluid then contacts the sample detection element. The top of the device must be removed to visualize the sample detection element. The extensions from the elongated passageway also serve to direct fluid flow to the surface of the sample detection element. In this invention the swab containing sample is not placed into the sample-processing device until it has been incubated in an extraction reagent and the extraction reagent has been allowed to saturate the fibers of the swab. The swab is inserted in the elongated feature until the tip is in fluid contact with the detection element.
U.S. Pat. No. 5,994,150 discloses an SPR-based detection system for optically analyzing a number of specific regions on a rotating platform.
Each of the foregoing U.S. Patents describing the background of the invention is hereby incorporated by reference in its entirety, including all tables, figures, and claims.
The present invention provides cost effective analytical instruments for determining the presence or amount of an analyte in a sample. The invention provides devices, instruments and methods useful to provide automated test results for single or low to medium sample volume applications, using an instrument that requires only a limited amount of laboratory space. The invention also addresses the technical limitations found in current automated analyzers by providing the analyzer with a test cartridge that contains all of the elements to conduct one or more assays or tests and provide results. The skilled artisan will readily appreciate that the test cartridge design of the invention is such that a number of different optical or electronic methods may be used to detect the analyte or provide a test result. The test cartridge of the invention is also designed to flexibly provide one or more analytical result.
SUMMARY OF THE INVENTION
The analytical, or medical point of care assay instrument and component aspects of the present invention provide self-contained sample processing and reagent capabilities for low to medium volume testing requirements. Representative testing applications include, but are not limited to, infectious disease testing, cancer detection and monitoring, genetic testing, therapeutic drug level monitoring, allergy testing, environmental testing, food testing, diagnostic and/or prognostic testing of human and veterinary samples, off-line process testing, etc. Preferably, the instrument uses an optical detection method based on a fixed polarizer ellipsometric method and a test surface designed for analysis of thin films. Particularly preferred embodiments of such methods and test surfaces are described in U.S. Pat. Nos. 5,494,829 and 5,631,171, which are hereby incorporated by reference in their entirety, including all figures. In certain of these embodiments, the test devices use a combination of thin films to modify the reflection of light from the surface of the test device. Alternatively, the instruments use a detection system, for example a spectrophotometric, chemilluminscent, fluorescent, or electrical potential detection method, that is consistent with the test surface, supporting reagents contained within an assay cartridge, and the signal produced from the test surface.
Assay cartridges are preferably single-use disposable elements designed to conduct a specific type of analysis. Such cartridges contain features that allow for multiple reagents to be stored separately within the cartridge unit. The cartridge also typically contains features that, in conjunction with instrument elements, can result in the delivery of those reagents in the proper sequence to the test surface. In these embodiments, the cartridge is capable of receiving a sample and, in conjunction with instrument elements, processing the sample for application to the test surface. A sample processing element of the cartridge includes the ability to receive and retain a sample collection device, e.g., a swab or a sample reservoir. In preferred embodiments, the sample processing element can retain the sample collection device in a stable configuration as the cartridge, or an element thereof, is indexed or moved to various analysis positions.
The sample processing element can be a separate component that is inserted into the cartridge during manufacturing, or attached by the user immediately prior to use. Alternatively, the sample processing element can be an integral part of the cartridge. Thus, while only a single cartridge design is required, the sample-processing element can be uniquely tailored to accept a wide range of sample collection devices or sample types. The selection of the sample processing element to be inserted into, or otherwise associated with, the cartridge is a function of the specific analysis the cartridge is designed to conduct. The sample processing element can be designed to accommodate a specific sample type, or may be designed to accommodate multiple sample types. In preferred embodiments, the sample processing element comprises a hinged extension designed to support the shaft of a swab-type sample collection device. When used, the hinged extension can prevent the swab shaft from being inadvertently dislodged, and can act as a signal to the instrument that a swab is in use. In other preferred embodiments, a filtration membrane is positioned below a small opening in the sample processing element through which a sample fluid must flow.
Assay cartridges of the invention are also designed to deliver the sample and the assay reagents to a test surface within the cartridge. The assay cartridge, in conjunction with the instrument, may be indexed in a specific sequence to allow the proper addition of reagents to the test surface or other regions of the cartridge. The instrument preferably indexes the cartridge such that the test surface is available for analysis at one or more stages in the assay process. The detection system included in the instrument is designed to be compatible with the type of test surface and reagents contained in the cartridge. For example, when the test surface is a membrane coated with an analyte-specific binding reagent and one of the reagents is an anti-analyte antibody derivatized with a fluorescent label, then the instrument can contain a fluorimeter for analysis. If the test surface is a series of micro-electrodes and the reagents are redox type reagents, the instrument can contain a detection system which provides a potentiometric result. In preferred embodiments, the assay cartridge is capable of generating a signal without addition of external signal-related reagents. For ease of presentation only, the test surface primarily discussed is an optically active test surface. However, those skilled in the art will recognize the flexibility and capabilities of test cartridge design and how to match those properties to a specific detection method within an automated instrument system of the invention.
Thus, in preferred embodiments this invention concerns assay cartridges that preferably comprise a bottom member and a top member, the bottom member comprising an optical reading well and a test surface, and the top member comprising a rotatable reagent carousel. The reagent carousel comprises a sample receiving port and a plurality of reagent wells. The reagent carousel has an opening that is aligned with the optical reading well containing the test surface when an analysis of the surface is to be performed. One or more reagent wells comprise a reagent and a reagent well piston for delivery of one or more reagents to the test surface and/or the sample receiving port. The top member attaches to the bottom member such that the reagent carousel may be rotated relative to the bottom member.
In another aspect, the invention concerns methods for producing an assay cartridge for a specific analysis and sample type. The assay cartridge can be fabricated using manufacturing techniques which are well known in the art. Preferably, the assay cartridge is fabricated by attaching the bottom member to the top member such that the rotatable reagent carousel may be rotated relative to the bottom member. Particularly preferred methods of fabricating the assay cartridges of the invention are described herein.
Yet another aspect of the invention concerns test kits for use with an analytical assay instrument, the test kit preferably comprising a number of assay cartridges specific to the analyte(s) the kit is designed to detect, and instructions for their use. Preferably, the kit includes one or more external kit control elements for additional quality control of the test procedure and equipment. Most preferably, such kits include appropriate sample collection device(s) (e.g., swabs, liquid sampling cups, etc.) which are consistent with the sample requirements for the types of analytes to be detected using the assay cartridges of the kit.
In particularly preferred embodiments, the assay cartridge comprises one or more of the following: (i) a test surface comprising an analyte-specific binding layer for immobilizing an analyte on the test surface; (ii) a test surface that nonspecifically immobilizes an analyte thereon; (iii) a test surface that is an optically active test surface; (iv) an optically active test surface that is adapted to generate an interference, ellipsometric, or polarization signal; (v) a rotatable carousel that further comprises a sample processing element; (vi) a sample processing element comprising a filtration surface; (vii) a sample receiving port adapted to receive a swab type sample collection device; (viii) a bottom portion of each reagent well sealed by a breakable seal material, and a top portion of each reagent well sealed by the reagent well piston in combination with a breakable seal material; (ix) reagent well piston(s) comprising a piercing element to break the breakable seal material sealing the bottom of the reagent well; (x) a bottom member comprising extender tabs or other mechanism adapted to ensure proper registration of the assay cartridge with an analytical instrument; and (xi) reagent well piston(s) comprising a hex boss element.
The assay cartridge is preferably made from a plastic material, such as polystyrene, which provides mechanical strength and stability. The skilled artisan will recognize that such assay cartridges, or components thereof, may be made from a number of thermoplastics which are suitable for injection molding. In preferred embodiments, the bottom member of the assay cartridge is made from a single piece of a plastic material. Most preferably, the bottom member of the assay cartridge comprises an upper and a lower section which are mated together. The top element comprising a reagent carousel can be made from any suitable material, preferably polyethylene that is stiffened with talc, to facilitate handling characteristics during manufacture. The reagent carousel is attached to the top member of the assay cartridge in a manner which allows for rotation of the reagent carousel relative to the bottom member.
The term “sample” as used herein refers to any specimen suitable for analysis within an assay cartridge according to the invention. Preferred sample types include, but are not limited to, a material, including biological material, collected on swabs (e.g., throat, vaginal, endocervical, rectal, urethral, nasal, or nasopharyngeal swabs), fluids, water, urine, blood, sputum, serum, plasma, fecal material, aspirates, washes, tissue homogenates or samples, process fluids, etc.
The term “sample collection device” as used herein refers to any support used for transfer of a sample into the device. Suitable sample collection devices are well known to those skilled in the art. Preferably, a sample collection device can be a swab, a wooden spatula, bibulous materials such as a cotton ball, filter, or gauze pad, an absorbent-tipped applicator, capillery tube, and a pipet.
A vacuum element can be used to express the sample from the sample collection device and to deliver the sample, or a portion thereof, to the optically active test surface. In preferred embodiments, the same vacuum source can be used to secure the cartridge to the instrument's cartridge platform and/or to promote sample and reagent flow through or over or around the optically active test surface. Alternatively, cartridge locking and positioning can also be accomplished by a mechanical element, such as locking mechanisms, or set pins. One or more different vacuum elements may also be used in order to separate the various vacuum functions that may be required to complete a particular assay.
A sample may be processed prior to moving from the sample processing element of the cartridge to the optically active test surface. To process the sample, one or more reagents are added to the sample collection device within the sample processing element. These reagents serve to extract, or free, analyte from the sample collection device and from the sample matrix or from an organism contained on the sample collection device. The reagents may assist in eliminating sample matrix effects such as inhibition or non-specific binding. The sample-processing element may also include a filter feature to remove particulates from a sample prior to introduction to the test surface.
In other preferred embodiments, the sample is processed, for example by filtration with or without subsequent extraction, prior to introducing the sample to the optically active surface. When a fluid such as urine or a suspension contains the analyte, the analyte may be retained on a sample processing element that contains a filtration surface. The sample is added to the sample receiving/processing assembly when the reagent carousel is rotated above an absorbent material located in the base of the cartridge. The absorbent material serves as a self-contained waste reservoir and does not expose other cartridge elements to the waste material. The sample fluid is drawn through the filtration surface by application of vacuum or other pressure differential. Once the sample fluid is filtered, extraction reagents can be applied to the filtration surface. The analyte is then solubilized within the extraction reagent prior to introduction to the optically active test surface. The sample-processing element is indexed to the test surface position and sample delivered. Assay processing proceeds as described herein.
The term “analyte” as used herein refers to any material that is a specific indicator of a disease, infection, drug level, analytical condition, environmental condition, process condition, medical condition, or any other condition that can be diagnosed or assessed by rapid, sensitive detection of the presence or amount of the analyte. Preferably, an analyte is an antigen, antibody, nucleic acid, metal, receptor, enzyme, enzyme substrate, enzyme inhibitor, ligand, chelator, hapten, drug, or analog, or any fragment of these materials.
In further particularly preferred embodiments, the assay cartridge comprises: (i) a sample receiving port capable of receiving a volume of fluid sample onto a concentrating element that is unique to the sample collection device or sample type; (ii) a sample receiving port comprising a retaining mechanism (e.g., molded fingers) to hold a swab type sample collection device in the proper position in the reagent carousel for subsequent processing; (iii) an optically active test surface positioned in the base of the cartridge, consisting of a low porosity material having one or more optical layers positioned thereon to create a surface with the proper optical characteristics for the detection method built into the instrument; and (iv) a reagent carousel in a plastic housing comprising one or more reagents.
The term “sample receiving port” as used herein refers to an opening in the assay cartridge which provides access to the interior of the cartridge. A suitable sample receiving port can be readily determined by one skilled in the art, based on the type of sample and/or sample collection device.
As discussed above, the sample processing element can be a separate component that is inserted into the cartridge during manufacturing or attached by the user, or can be an integral part of the cartridge. The sample processing element is preferably designed to accommodate a specific sample type for a specific test method and analyte. In preferred embodiments, a sample delivery port is fully integrated into a reagent carousel section of the cartridge, and contains an appropriate reagent delivery configuration. In other preferred embodiments, the reagent delivery configuration allows an extraction reagent to flow into a groove or channel at the top of the sample receiving port for extraction of an analyte from the sample collection element.
Preferably, a swab is used as a sample collection device, and the sample processing element comprises a swab holder or a swab processing insert. The swab holder or swab processing insert can be tapered or angled to allow a single sample processing element to accommodate all types of swabs by allowing swabs with different amounts of fiber, or that are wound to different levels of tightness, to be held securely within the holder or insert. Most preferably, the swab holder or swab processing insert securely holds the swab to provide stability during reagent cartridge indexing, and to provide a vacuum seal to assist in fluid flow around and through the swab.
The term “test surface” as used herein refers to a surface within the assay cartridge which is adapted to provide a detectable signal corresponding to the presence or amount of an analyte in a sample. Most preferred are optically active test surfaces, as defined herein. The test surface can be made available to the detector element of the instrument through an optical reading well in the upper section of the assay cartridge. The term “optical reading” well as used herein refers to an aperture or opening in the assay cartridge through which the test surface can be optically read or analyzed by a detector appropriate for the type of signal generated at or by the test surface.
When designing and constructing a test surface according to the invention, it is preferred that such a surface be adapted to specifically bind an analyte of interest, unless an analyte which is nonspecifically immobilized on the test surface can be specifically detected. Therefore, the test surface preferably comprises an analyte-specific binding layer to immobilize one or more analytes of interest on the test surface. The analyte-specific binding layer may be any material that will specifically interact with an analyte in a test matrix and retain that analyte throughout the assay procedure, or until a signal is detected from the test surface. Most preferably, an analyte-specific binding layer can comprise an antibody, antigen, a nucleic acid, enzyme, enzyme substrate, enzyme inhibitor, receptor, ligand, metal, chelator, complexing agent, hapten, or analog, or a fragment of any of these materials. In construction of an optically active test surface, it may be advantageous to add a layer of material to provide long term stability of the analyte-specific binding reagent. This layer is removed during the assay procedure or does not interfere with the assay procedure.
The analyte-specific binding layer may be applied to a test surface, preferably an optically active surface, by a number of different processes. The skilled artisan will recognize that such processes will depend on the nature of the molecules to be employed to specifically bind the analyte(s). In preferred embodiments, the analyte-specific binding layer is coated to the entire surface by submersion in a liquid coating solution, or applied by micro-spotting, ink jetting, or other printing type processes. The analyte-specific binding layer may be applied as a single spot of a specific diameter determined by the volume and viscosity of the coating solution and the wettability of the surface. The analyte-specific binding layer may be applied as a line or other symbol using commercially available processing equipment.
In other particularly preferred embodiments, test surfaces of the invention comprise a plurality of analyte-specific binding layers, each comprising one or more binding reagents specific for a different analyte. Preferably, binding reagents are applied to the test surface in a plurality of zones, thus allowing for the detection of multiple analytes from a single sample in a single analysis. Thus, the analyte-specific binding layer can preferably be applied as a series of stripes, dots, or other symbols in any desired array. The size of the array placed on the test surface is limited by the available test surface area, the spatial resolution required to uniquely identify each position within the array, the detectors spatial resolution capabilities, and the spatial resolution of applying the analyte-specific binding layers. In addition to the analyte-specific binding layer, various analysis controls, e.g., positive and/or negative control zones, can also be applied to the test surface for use in quality control of the test result.
To improve the sensitivity of the testing method, once an analyte is associated with its analyte-specific binding reagent on the test surface, a secondary reagent that includes an analyte-specific binding reagent may be used. This additional analyte-specific reagent may include additional reagents specifically associated with it to amplify the binding of analyte to the optically active test surface or when other surface constructions are used to provide for signal generation. Preferably, these additional reagents are selected from the group consisting of enzymes, film forming particles, catalytic reagents producing an insoluble product, self-assembling molecules, or other materials that will increase the optical thickness of the analyte layer. When the test surface construction does not include optically functional layers, the amplifying reagents are solely responsible for signal generation. If an analyte-specific binding reagent is not used on the test surface, the analyte may be retained by nonspecific interaction with the test surface. Specificity for this type of assay is obtained with a secondary analyte-specific reagent.
The term “optically active test surface” as used herein refers to a test surface which is adapted to alter incident light. Incident light refers to any electromagentic radiation which impinges on the surface. Preferably, incident light is unpolarized light, polarized light, eliptically polarized light, linearly polarized light, monochromatic light, polychromatic light, visible light, ultraviolet light, and infrared light. Methods for preparing an optically active test surface are known to those skilled in the art. Preferred methods for preparing an optically active test surface are described in PCT International Publication Number WO 94/03774 and U.S. patent application Ser. No. 08/950,963, filed Oct. 15, 1997 each of which is hereby incorporated by reference in its entirety, including all figures, or according to similar optical principles. Preferably, the optically active surface is sealed into a position in the base of the cartridge such it is not distorted by the application of the vacuum source. Particularly preferred sealing processes are heat sealing, pressure sensitive adhesives, adhesives, sonic welding, or ultrasonics, and similar processes.
The term “optically functional layer” as used herein refers to a layer (or layers) that can produce a signal upon binding of an analyte to the receptive material. The layer may have one or more coatings, including a base layer with or without an antireflective (AR) layer, designed to modify the optical properties of the support material so that the desired degree of reflectivity, transmittance, and/or absorbance suited to the final assay configuration is obtained. The optically functional layer may attenuate one or more, or a range of wavelengths of light so that a result is observable in an instrumented analysis in the final device upon analyte binding. The attenuation of light may involve the extinction or enhancement of specific wavelengths of light as in an AR coated assay device for a visually observable color change. Or the intensity of a specific wavelength of light may be modified upon reflection or transmittance from the final assay device. The generation of an AR effect is not required for the instrumented detection of the thin film effect. In all cases the optically functional layer serves to attenuate the light incident on the optically active test surface through the interaction of the light with the thin films on the optically active test surface. The optically functional layer may also modify the optical parameters of the device to allow a change in the state or degree of polarization in the incident light. Optically functional layers include amorphous silicon, silicon nitride, diamond like carbon, titanium, titanium dioxide, silicon dioxide, silicon carbide, silicon oxynitride, silicon monoxide, and other related materials or composites of these materials. A preferred construction of optically functional layers is a layer of amorphous silicon coated onto a polycarbonate membrane and then coated with a layer of diamond like carbon. Another preferred construction of the optically functional layers is a layer of amorphous silicon coated onto a polycarbonate membrane then coated with a layer of silicon nitride and a thin layer of diamond-like carbon. Optically functional materials may be applied to the support material by sputtering, ion beam deposition, vapor deposition, spin coating, direct current plasma, chemical vapor deposition, or other methods known to those skilled in the art.
The base optical layer serves to provide the optical characteristics required for creating the appropriate reflectance, adsorption, or transmission properties. It must be sufficiently dense to eliminate stray light leakage or back scattering from the backside of the support. As the thickness of the base layer increases so will the percent reflectance of the modified support. The desired percent reflectivity will depend on the optical system incorporated into the instrument. Appropriate base layer material includes amorphous silicon, polycrystalline silicon, lead telluride, titanium, germanium, chromium, cobalt, gallium, tellurium, or iron oxide. The final optical properties of the optically active test surface are optimized to consider the optical contribution of all layers of the final test surface. Thus, the base optical layer may be adjusted based on empirical testing or thin film reflection theory modeling to account for the attachment layer or the analyte-specific binding layer or any other layer that will be present in the final optically active test surface.
The optically functional layer may serve to provide the desired optical properties and may also serve as an attachment layer. An additional layer may be applied in the construction of the optically active test surface that serves the sole purpose of an attachment layer.
In particularly preferred embodiments, the optically active surface: (i) has an analyte-specific binding reagent immobilized on the surface; (ii) is able to non-specifically capture the analyte to be detected; (iii) is reflective and capable of generating an interference signal upon addition of a specific analyte or target to the optically active surface during performance of the assay steps; (iv) is reflective and capable of generating an ellipsometric signal upon addition of a specific analyte or target to the optically active surface during performance of the assay steps; (v) is reflective and capable of generating a polarization signal upon addition of a specific analyte or target to the optically active surface during performance of the assay steps; and (vi) the interference, ellipsometric, or polarization signal is related to the presence or amount of the specific analyte or target.
An additional attachment layer may be applied to the optical materials to improve their binding and retention of the analyte-specific binding layer or to other types of test surfaces as well. An attachment layer is any material or combination of materials that promote or increase the binding of the receptive material to the optically functional layer. Also, the attachment layer should retain the receptive material with sufficient avidity for all subsequent processing and assay steps. Preferably, the attachment layer should not reduce the stability of the receptive material and should insulate the receptive material from the optically functional layer or layers thereby improving the stability of the receptive material. When no receptive layer is utilized, the attachment layer may be used to non-specifically bind the analyte of interest. Attachment layers can be constructed of silanes, siloxanes, polymeric materials, nickel, diamond-like carbon, and the like. The attachment layer may be applied by vapor phase deposition, solution coating, spin coating, spray coating, a printing-type process, or other methods known in the art. A list of appropriate attachment layers and ways to identify attachments layers is described in U.S. Pat. No. 5,468,606 incorporated herein by reference in its entirety.
The attachment layer should also assist in the stabilization of the analyte-specific binding layer. When an attachment layer is employed, the material can be applied by exposure of the test surface to a vapor of the material under vacuum. Or the layer may be created by solution coating, by spin coating, by ink jetting, by printing processes, or other methods for application of a thin layer of the desired material. Once the material is applied to the test surface, a curing step may be employed to ensure permanent adhesion of the layer to the test surface. Curing is generally accomplished by exposure of the test surface to an elevated temperature for a period of time. The thickness of the attachment layer preferably provides sufficient density to the analyte-specific binding layer and separates the binding layer from the test surface, particularly when an optically active test surface is used. The attachment layer is then applied to the optical materials. The attachment layer may be used in some applications for the nonspecific capture of the analyte of interest. Construction of test surfaces other than optically active test surfaces may not require the use of an attachment layer.
The terms “film” and “thin film” as used herein refer to a one or more layers of sample material deposited on a substrate surface. A film can be about 1 Å in thickness, about 5 Å in thickness, about 10 Å in thickness, about 25 Å in thickness, about 50 Å in thickness, about 100 Å in thickness, about 200 Å in thickness, about 350 Å in thickness, about 500 Å in thickness, about 750 Å in thickness, about 1000 Å in thickness, and about 2000 Å in thickness. Particularly preferred are films from about 5 Å to about 1000 Å in thickness; most preferred are films from about 5 Å to about 750 Å in thickness.
In other particularly preferred embodiments, the reagent carousel: (i) can be freely rotated on the bottom member through about 90°, 120°, 150°, 180°, 210°, 240°, 270°, 300°, 330°, and most preferably 360°, without binding or catching on any other portion of the instrument when the sample collection device is inserted in the sample receiving port; (ii) is mated to the upper surface of the bottom section of the assay cartridge, where the bottom section is formed of two molded plastic articles that may be sealed to create the bottom section of the overall assay cartridge; (iii) the upper surface of the bottom section includes one or more elements such as extender tabs or set pins; and (iv) the bottom surface of the bottom section contains one or more elements such as indentations for ensuring that the cartridge is in the proper position and orientation to conduct the assay method as well as improve the users' grip on the test cartridge when loading on the instrument.
The term “extender tabs” as used herein refers to elements which extend from the assay cartridge and assist in orienting the cartridge within the instrument. Extender tabs are in the raised position in the final assembled assay cartridge and serve to lock the reagent carousel into place. When the cartridge is in proper registration within the instrument, the tabs are pushed down and the reagent carousel is free to rotate. The cartridge may be held in place in the instrument by a variety of mechanisms well known in the art. Preferred means of providing alignment and stability of the cartridge can be application of vacuum, by means of force applied by a presser foot, release arms and/or by a lock and key type matching of the cartridge bottom to the instrument cartridge slot, or simple matching of set pins of sufficient height to stabilize and retain the cartridge.
In other particularly preferred embodiments: (i) reagents are sealed within the reagent carousel by a thin layer of a breakable vapor seal material at the bottom of a reagent well; (ii) reagents are sealed within the reagent carousel by a thin layer of impermeable, vapor seal material at the upper opening of the reagent well; (iii) the upper reagent well seal is in contact with a reagent well piston; (iv) the reagent well piston is a rigid (e.g., plastic) element designed with a receiving element for a plunger element for driving the piston (e.g., a hex boss) in the uppermost segment of the piston, such that the uppermost segment of the piston extends above the upper surface of the reagent carousel section of the cartridge; (v) the hex boss is designed to mate with a push rod of the plunger element in the instrument housing; (vi) the push rod mates with the hex boss, or other receiving element of the piston, and a vertical drive element pushes the piston through the lower impermeable vapor seal to release reagent onto the optically active surface; (vi) the plunger element draws the piston back into the upper position to allow proper motion of the cartridge to the next assay position; and (viii) the plunger element includes an optional presser foot to improve registration of the reagent carousel and the membrane holder within the cartridge.
In another particularly preferred embodiment, the reagent well piston is pushed down with a plunger element, but is not equipped with a receiving element for said plunger. Instead, the plunger pushes the piston by contacting the uppermost surface of the piston without mating to a element such as a hex boss. As the plunger does not mate with the piston, it does not draw the piston back into the upper position, but allows it to stay in the depressed position.
The term “vapor seal material” as used herein refers to a breakable sealing material which provides a liquid- and vapor-impermeable barrier at the top and/or bottom of each reagent well. The vapor seal material is intended to be broken by application of force by a reagent well piston at an appropriate point in the assay procedure, in order to provide flow of reagent. Suitable vapor seal materials are well known to those skilled in the art. Particularly preferred vapor seal materials are mylar and low density polyethylene. In preferred embodiments, the vapor seal material is affixed to the reagent well by an adhesive. The vapor seal material may also comprise additional layers of material such as foils, papers, additional plastics, and the like. Preferably, the vapor seal material comprises a layer of 15 pound polyethylene, a layer of aluminum foil, a layer of 7.2 pound polyethylene, and a layer of 25 pound ClF coated paper (Genesis Converting Corporation). Those skilled in the art will recognize that other materials of similar composition may substitute in the vapor seal material.
The term “reagent well” as used herein refers to a chamber in the carousel that contains a reagent for use in an assay procedure. A reagent may be any suitable reagent, including but not limited to a wash reagent, a buffer reagent, an extraction reagent, a neutralizing reagent, an amplifying reagent, or a signal generating reagent, as defined herein.
The term “reagent well piston” as used herein refers to an element that provides positive pressure to the reagent well for delivery of a reagent. A preferred material for the reagent piston is polycarbonate. The reagent well piston is pushed by a plunger mechanism of the instrument, creating sufficient force to break the lower seal of the reagent well and deliver fluid from the reagent well. The reagent well piston may contain an element to ensure positive engagement by the plunger mechanism. In a preferred embodiment, the element that ensures positive engagement is a hex boss. The reagent well piston may comprise a piercing element to assist in breaking the lower reagent well seal. The reagent well piston may or may not need to be retracted back into the reagent well once it is used to pierce the reagent seal, depending on the carousel design and whether the piston will prevent reagent carousel rotation. A piston design that need not be retracted may not require the hex boss element, as it need not seat with the push rod mechanism. The reagent well piston can also serve to assist in sealing the upper portion of the reagent well.
The piston design, the rate that the plunger mechanism displaces the piston in the reagent well, and/or the aperture size for the reagent well can allow for control of the reagent flow to the test surface. Piston design and displacement can also be used to control the amount of reagent delivered to the test surface. The piston may be designed with grooves of various shapes and sizes and numbers. The contour and number of grooves in the piston will modify the fluid flow rate through interactions such as surface tension and retention of the fluid contact with piston material as the piston is displaced. The piston design and the rate of displacement, as well as the materials in the lower vapor seal, determine the aperture size for the dispensing of the reagents. The quality of the aperture is also important in determining fluid flow rate. The quality of the aperture generated means the size of the opening, the structure of the opening, the cleanliness of the opening, etc. The piston design and the lower vapor seal as well as the displacement rate of the piston must be evaluated together to optimization reagent dispensing.
The term “hex boss” as used herein refers to a raised element at the top of the reagent well piston comprising a hexagonally-shaped recess. In preferred embodiments, the plunger mechanism mates with the hexagonal recess to ensure positive engagement of the reagent well piston by the plunger. Those skilled in the art will recognize that the recess need not be hexagonally shaped, but rather can be any shape which is capable of mating with the plunger mechanism. The plunger mechanism can also be designed with spring-loaded mechanisms to control the push rod. Release of tension on the spring mechanism allows the push rod to displace the piston. If different pressures are required to break the reagent seals concentric push rods can be designed with different spring tensions to deliver varying displacement capabilities.
In another aspect, the invention concerns analytical instruments that comprise or utilize assay cartridges according to the invention, a mechanism, element or subassembly for receiving the assay cartridge, one or more rotation elements or subassembly to rotate and index the reagent carousel, a plunger element or subassembly for engaging the reagent well pistons to deliver reagent from the reagent wells to the sample receiving port and/or the test surface, a vacuum element or subassembly for directing sample and/or reagent to the test surface, and a detector for detecting a signal from the test surface. Preferably, a control processor controls the rotating, plunger, and vacuum elements according to an assay algorithm, and a signal processor for relating the generated signal to the presence or amount of an analyte.
In particularly preferred embodiments, the analytical instruments of the invention comprise one or more of the following: (i) a presser foot for stabilizing the assay cartridge; (ii) an optical control element for determining cartridge orientation; (iii) a rotation element comprising a mechanical arm and motor; (iv) a plunger element comprising a push rod attached to a vertical drive element; (v) a push rod adapted to seat in a hex boss element on the reagent well piston; (vi) a push rod that returns the reagent well piston to about its original position in the reagent well following delivery of the reagent; (vii) a detector selected from the group consisting of a color sensor, a color detector, an image detector, a spectrophotometer, a luminometer, a fluorometer, a potentiometer, an interferometer, a polarimeter, and an ellipsometet; (viii) a detector that is a fixed polarizer ellipsometer; (ix) a control processor and a signal processor consisting of a single general purpose computer programmed to perform instrument control and data processing algorithms; (x) an assay cartridge comprising an identifying element which identifies the analyte and/or the sample to the analytical instrument; (xi) an assay cartridge comprising an identifying element that is a bar code, and a bar code reader configured to read the bar code; and (xii) a sample receiving port adapted to receive a swab type sample collection device.
The analytic instruments preferably comprise an element for detecting a signal from the test surface. Depending upon the type of assay to be performed, the detector can be a color sensor, a color detector, an image detector, a spectrophotometer, a luminometer, a fluorometer, a potentiometer, an interferometer, a polarimeter, and an ellipsometer. One skilled in the art can readily match a suitable detection element to the assay being performed. Most preferably, the detection element is a fixed angle ellipsometer.
The term “interference signal” as used herein refers to a change in the wavelength (“color”) of light reflected by an optically active surface, due to changes in the optical thickness of the sample material adsorbed or specifically bound to the surface. Interference may be measured and related to the presence or amount of the specific analyte or target by techniques that are well known in the art.
The term “ellipsometric signal” as used herein refers to a change in the elliptical polarization of light reflected by an optically active surface, due to changes in optical thickness of the sample material adsorbed or specifically bound to the surface. An ellips 6 metric signal may be measured and related to the presence or amount of the specific analyte or target by techniques that are well known in the art.
The term “polarization signal” as used herein refers to a change in the linear polarization of light reflected by an optically active surface, due to changes in optical thickness of the sample material adsorbed or specifically bound to the surface. A polarization signal may be measured and related to the presence or amount of the specific analyte or target by techniques that are well known in the art.
In particularly preferred embodiments, the analytical instrument: (i) comprises a user interface element; (ii) comprises a control processor; (iii) comprises a signal processor; (iv) comprises an algorithm for signal processing and data classification; (v) comprises an algorithm for determining an assay sequence; (vi) receives one or more assay cartridge(s) and completes the assay protocol independent of the user; (vii) mechanically indexes the assay cartridge so that the optically active surface of the cartridge is available for analysis at one or more stages in the analysis process; (viii) comprises a carousel rotation element consisting of a mechanical arm and a motor which indexes the reagent carousel to different positions for delivery of reagents to the optically active surface of the cartridge in the appropriate sequence; and (ix) comprises one or more optical control elements, such as optical encoders or bar code readers, for reagent carousel indexing, cartridge positioning, and determining cartridge orientation, and establishing the analytical method to be used and type of result to be reported.
The term “user interface” as used herein refers to an element of the instrument which allows the user to provide information and/or instructions to the device, and/or for the device to provide information and/or instructions to the operator. Those skilled in the art will recognize appropriate user interfaces. For example, a user interface can be one or more of the following: a bar code reader, a keyboard, a computer “mouse,” a light pen, a computer screen, and a computer printer.
The term “algorithm” as used herein refers to a sequence of steps to be followed to perform an assay and/or analyze data obtained from an assay. In preferred embodiments, an algorithm is stored on a control processor which controls the operation of the analytical instrument, and/or a signal processor which processes a signal generated from the test surface into a meaningful assay result. Preferably, the control and signal processors are one or more general purpose computer elements or computer chips which are programmed with the appropriate algorithm.
The term “daemon” as used herein refers to a process that occurs in the background and is invisible to the user. Preferably, daemons run continuously throughout the assay procedure. A daemon may also be referred to as a background procedure or a background thread of execution.
The term “index” as used herein refers to positioning of an assay cartridge in specific orientations. A cartridge can be indexed so that discrete locations on the cartridge, for example a reagent well and the test surface, precisely align with one another for properly timed and/or positioned reagent delivery. Preferably, analytical instruments of the invention use a mechanical mechanism or subassembly for cartridge indexing.
The term “optical control elements” as used herein refers to a optical sensor mechanism which determines the orientation of a cartridge element. Appropriate optical control elements are well known in the art.
Preferably, one or more parameters required for proper sample processing can be provided by the user through the user interface of the instrument. For example, a user may indicate the sample type, the type of sample collection device, and/or the assay protocol. Most preferably, however, the assay cartridge is configured during manufacture such that each combination of assay type, sample collection device, etc., is represented by a distinct assay cartridge which can be recognized by the instrument and distinguished from other cartridges. The distinct assay cartridge can provide the appropriate reagent carousel for the assay, as well as the sample retention and extraction mechanism required by a given sample collection device. For example, for swab-type sample collection devices, a sample retention mechanism must also serve to direct extraction fluid into the swab fibers and not just around the swab fiber. Assay sequence, incubation times, and other parameters can be pre-set for each cartridge design. Cartridge lot information may also prompt the instrument to select the proper assay parameters and sequence as well as data analysis method. Alternatively, data processing may occur manually by the user.
In other particularly preferred embodiments, the vacuum element of the analytical instrument: (i) comprises a single vacuum source having one or more vacuum ports; (ii) uses vacuum for cartridge retention and stability, reagent flow through, sample extraction, and test surface drying; (iii) uses vacuum to direct fluid to flow through or over or around the optically active surface and into a waste adsorbent material or reservoir within the cartridge; and (iv) incubates a sample, or a component thereof, on the surface of the optically active surface for a period of time under normal gravity conditions prior to reagent transfer through or around the optically active surface by vacuum.
Preferably, the vacuum source maintains a weak (about 20 mm Hg to about 40 mm Hg; preferably about 30 mm Hg) vacuum when the test surface is positioned for reading through the optical reading well. In other preferred embodiments, the vacuum source is disengaged during incubations on the test surface and/or when the reagent carousel is indexed. The vacuum level can preferably be raised to between about 120 mm Hg and about 180 mm Hg, most preferably about 150 mm Hg, in order to dry the test surface prior to reading, to draw extraction reagent from a swab, or to draw a fluid through a concentrating membrane prior to extraction. One skilled in the art will recognize that the vacuum required for reagent flow can vary, depending on the composition of the reagent and the composition and porosity of a membrane, filter, or test surface. A feedback loop to vary the vacuum level dependent upon sample or test conditions may be incorporated to automatically adjust the vacuum in the device to accommodate a number of parameters affecting reagent flow.
In further embodiments, a series of pneumatic valves may be added under the cartridge receiving stage of the instrument. These pneumatic valves allow the introduction of air into or over various parts of the cartridge or instrument. The air flow may be directed onto the optically active test surface to assist the vacuum system in drying the test surface. Or the air flow may be used to assist in fluid movement.
In other particularly preferred embodiments: (i) the instrument uses fixed angle ellipsometry as the optical analysis feature; (ii) the instrument comprises an LED light source; (iii) the LED light source emits light at 525 nm; (iv) the LED light source is positioned at a 20° angle of incidence relative to a line normal to the plane of the optically active test surface; (v) a photodiode detector is positioned at a 20° angle of detection relative to a line normal to the plane of the optically active test surface; (vi) polarizing and analyzing polarizers are positioned at 90° relative to one another; and (vii) the instrument allows for synchronous detection to eliminate stray light as a source of noise.
The term “light source” as used herein refers to any source of electromagnetic radiation. Electromagnetic radiation can also be referred to as “light.” Such electromagnetic radiation may include wavelengths from about 10 −6 μm to about 10 8 μm; preferred is electromagnetic radiation from the ultraviolet to infrared wavelengths; particularly preferred electromagnetic radiation is visible light. Suitable light sources are well known to those skilled in the art, and can include any source of monochromatic or polychromatic radiation. The use of monochromatic radiation is preferred. The terms “monochromatic radiation” or “monochromatic” light as used herein refer to electromagnetic radiation having a bandwidth that is sufficiently narrow to function as a single wavelength for design purposes. Preferred light sources are lasers, laser diodes, and light emitting diodes (LEDs). In preferred embodiments, an aperture, preferably a bar-shaped aperture, is placed in the optical path, oriented parallel to a stripe-shaped capture zone on the test surface. The aperture can provide a larger interrogation area of the test surface, rendering the detector less susceptible to surface variations in the test surface and providing a larger area over which signal is averaged.
As used herein, the term “detector” refers to any device for detecting electromagnetic radiation by the production of electrical or optical signals, and includes color sensors, color detectors, image detectors, spectrophotometers, luminometers, fluorometers, potentiometers, interferometers, polarimeters, and ellipsometers, whether these detectors are driven to provide analog or digital signals, as well as any other light detection device. Preferred detectors detect electromagnetic radiation, particularly visible light, with the resulting production of electrical or optical signals. A signal processing element can process these signals to yield this information, for example by the use of standard curves, to associate the signals with an optical film thickness. In especially preferred embodiments, the optical film thickness is interpreted as a binding assay result, e.g., the result of a test showing either a positive, negative, or inconclusive result in a test for a specific analyte.
Preferably, the light source and detector of the instrument are positioned at an angle of incidence of between about 10° and about 40° relative to a line normal to the plane of the optically active test surface. Most preferably, the angle of incidence is about 10°, 20°, 30°, and 40°.
The term “polarizer” as used herein refers to a device that receives incoming electromagnetic radiation, and produces therefrom radiation which is polarized. Suitable polarizers, such as polarizing filters and analyzers, are well known to those skilled in the art. As described herein, polarizers can be positioned to polarize incoming light from the light source prior to contact with the sample under study, as well as light reflected from the sample under study. A polarizer can be fixed within an optical pathway. Alternatively, one or more of the polarizers can include a mechanism for varying s- and p- components of polarized light with time by rotating the polarization element, or a component thereof, on its optical axis. Preferably, this mechanism rotates a polarizing filter that is located in the position of a polarizer or analyzer in a conventional ellipsometer. Rotation of a polarizing filter provides a corresponding quasi-sinusoidal intensity in the electromagnetic radiation that is reflected from the sample under study.
The terms “polarizing polarizer” and “analyzing polarizer” as used herein refer to polarizers which interact with incident light prior to and following light impinging on the optically active test surface. In preferred embodiments, the polarizing and analyzing polarizers are set at about 70° to about 110° relative to one another. Most preferably, the polarizing and analyzing polarizers are set at about 70°, 80°, 90°, 100°, and 110° relative to one another.
The term “linear polarization” as used herein refers to a polarization state that is essentially all s-polarization or all p-polarization. Electromagnetic radiation is linearly polarized if, in either linear state, there is not enough of the other polarization state to affect the outcome of the measurement. Preferably, a linear polarizing filter may be rotated up to about 20° rotation off of its optical axis without introducing appreciable measurement errors.
In another aspect, the invention concerns methods of determining the presence or amount of an analyte in a sample. The method comprises providing an assay cartridge and an analytical instrument as defined herein, placing the sample into the sample receiving port of the assay cartridge, placing the assay cartridge into the receiving mechanism of the analytical instrument, performing an assay using the analytical instrument according to an assay algorithm, and using the signal processor to determine the presence or amount of the analyte in the sample.
In particularly preferred embodiments, a sample is selected from the group consisting of a throat swab, a vaginal swab, an endocervical swab, a rectal swab, a urethral swab, a nasal swab, a nasopharyngeal swab, a fluid, water, urine, blood, sputum, serum, plasma, an aspirate, a wash, a tissue homogenate, and a process fluid.
The preferred methods of using the instrument and cartridge include methods for analyzing the data and reporting a result. Preferred methods of use will be described in terms of a reagent or assay cartridge that is designed to detect an analyte on an optically active test surface where the optical detection system is based on a fixed polarizer ellipsometer. Those skilled in the art will recognize that methods for use of the instrument and the reagent cartridge will be similar for any other combination of analyte, test surface, and detection system.
In using the system, a user selects the reagent cartridge designed for the analyte of interest, for example a reagent cartridge designed to detect a particular microorganism. In particularly preferred embodiments, a microorganism is a bacterium, a virus, or a fungus, and most preferably a pathogenic bacterium, virus, or fungus. The user provides a specimen from the patient to be tested for the analyte of interest, collected, for example, using a throat swab. The user enters or scans (e.g., by bar code) the specimen identification number and the reagent cartridge lot information. Alternatively, the instrument may read the bar code on the top, side, or bottom of the cartridge when it is placed in the instrument. A bar code, or other identifying element of the cartridge, can provide information to a “Dallas” chip which provides the instrument with assay a quality control parameters, a lot number, a sample type, etc. The user places the throat swab in the sample receiving port in the reagent cartridge and loads the cartridge into the instrument. The instrument may close a door behind the reagent cartridge for orientation and stability or it may pull the cartridge into the appropriate slot with a cassette player type mechanism. The cartridge may be placed or set on alignment or set pins formed on and above the cartridge receiving stage. The set pins assure that the cartridge is properly oreinted. The rotation element may serve as one of the set pins. Preferably, the instrument receives the cartridge in proper registration and alignment so that the cartridge may be mechanically indexed through the appropriate sequence of reagent additions and incubation steps. The user may then enter a “start analysis” command via the user interface of the instrument, or the optical sensor that detects the presence of a cartridge may cause the initiation of the assay protocol.
The instrument then rotates the reagent carousel into a position so that the optically active surface may be scanned to provide a baseline reading. The optical scanning procedure may be conducted on one or more fixed points within the optical reading well or may be a linear segment of the optically active test surface or may analyze the complete test surface. The optical detection system does not move but the cartridge may be linearly displaced to expose a new section of the optically active test surface at each reading point.
A possible reading scheme occurs as follows. The collected data is stored for use in the final data analysis routine. For the baseline scan the cartridge is rotated to the optical read window. The cartridge is moved along the instruments positive y-axis so that the beam spot is positioned on the outer edge of the read area's periphery. The cartridge is moved along the negative y-axis and readings are taken every 12.7 microns. The sample size is dependent on the beam size and configuration and the number of samples per unit area needed to provide the accuracy desired in the final result. The raw data is stored in a file. The first column of raw data is the position of the read area on the optically active test surface. The second column is the corresponding reflected signal in millivolts for the baseline scan. The same process is repeated at appropriate assay steps. The multiple reads provide QC checks of the test cartridge and can stop a test if the readings at a specific stage fall out of a pre-set range. The multiple reads per assay allow for a test generating high noise to be rejected earlier in the analysis process.
The data analysis software can then align multiple scans of the same surface by selecting an edge feature to align each scan relative to the other scans, and thus provide for proper data comparisons. The edge features can be eliminated from the data analysis routine. The readings can be taken at any index distance desired and the degree of overlap selected to provide the most accurate level of result. It should, however, be set at the minimal acceptable value as the number of measurements made will also affect the time to result. The final method of data analysis can be tailored to the type of test method used, the required accuracy and precision, and other parameters determined by the intended use of the test result. Acceptable data analysis routines are known to those skilled in the art but could include peak to peak comparisons, peak smoothing, or other methods for normalizing the collected data or methods for data reduction. Another option might be to do image processing of the surface. In this case, each scan taken will visualize the entire test surface. Images would be compared between scans and appropriate data selected to provide the final test result. One or more of the detection scans described in the previous procedure may not be required for all detection methods and detection surfaces. However, one or more scan is required to provide sufficient information for data normalization.
Once the baseline scan is complete, the instrument activates the extraction reagent well and causes an extraction reagent to flow into the sample receiving port. The reagent carousel will be indexed by rotation to align the sample receiving port over the optically active test surface. Following a pre-set extraction period, the vacuum system can draw the sample fluid from the sample collection device through a filter to remove particulates, and onto the optically active test surface. Vacuum must be applied to the sample processing element such that sample fluid or processed sample fluid is drawn through the filter of the sample-processing element and onto the optically active test surface without being drawn through the optically active test surface. This is achieved by placement of a vacuum port between the sample-processing element and the optically active test surface so that the fluid will only flow to the optically active test surface and not through, over, or around it.
Following sample addition and a pre-set incubation, the reagent carousel rotates to align the proper reagent well with the optically active test surface. The sample may be added in the presence of a neutralizing agent that is added to the test surface prior to the addition of sample from an appropriate reagent well. The plunger mechanism of the instrument forces the piston to break the reagent seal and deliver the fluid to the optically active test surface. By using the piston and plunger mechanism, the flow rate of reagent delivered to the test surface can be controlled. Fluid is positively displaced by the piston and delivered to the optically active test surface under gravity and positive displacement. In this case positive displacement does not include any aspiration or introduction of air but is a mechanical method for positive displacement. The reagent will combine with the test sample on the surface of the optically active test surface. Following a pre-set, static incubation period, the fluid will be drawn through or over or around the optically active test surface by activation of the vacuum system and all liquid waste is retained within the assay cartridge. When analyte is present in the neutralized sample, analyte will bind in one or more positions to the analyte-specific binding layer on the optically active test surface. After specific reagent additions, the test surface may be washed with a solution from one or more reagent wells to remove any unreacted reagents. After wash steps the test surface may be dried by a combination of vacuum and air flow, by vacuum alone, or by air flow alone.
Next, a new reagent well aligns over the optically active test surface and a wash solution is delivered. All reagent additions occur with the vacuum system in the disengaged position. Once the reagent is delivered and the pre-set period is past, the vacuum system is engaged to draw the fluid through or around or over the optically active test surface. Reagent removal is controlled by application of the vacuum. The static incubation improves assay performance while the flow through process simplifies assay processing. The test surface may be rinsed with one or more wash reagents from one or more reagent well. Once the optically active test surface is rinsed, the reagent carousel is rotated to the optical reading well and the optically active test surface is scanned again to look for non-specific binding and debris from the sample and to qualify the optically active test surface integrity. A scan following the addition of sample is required to assist in normalizing the data. An amplifying or signal-generating may also be added to the test surface together with the analyte when appropriate for the type of test surface employed.
Upon completion of the second optical scan, an amplifying reagent, or signal generating reagent (depending on the test surface) can be applied to the optically active test surface by rotation of the appropriate reagent well over the test surface. The amplifying reagent is allowed to react for a period of time and then the vacuum system is engaged to draw the unreacted reagent through or around or over the optically active test surface. The reagent carousel is again rotated to align a reagent well over the test surface and a wash solution applied. The reagent seal is pierced as with the original reagent delivery and the vacuum is engaged at the appropriate time. The vacuum will serve to dry the optically active test surface. A small air-flow device may be included to improve the speed of the surface drying. When a test surface is not optically active then this final drying step may not be required.
Once the optically active test surface is washed and dried then a final optical scan is conducted. The optical reading well of the reagent carousel is rotated over the test surface and the scan conducted. The optical scans may occur with the vacuum system engaged if no distortion of the test surface occurs under vacuum. Positive report of analyte binding is provided only when sufficient signal intensity is observed and the proper sequence of elements on the test surface are identified.
The instrument component list preferably includes an optical detection element preferably contained in a single common unit that may be attached to the instrument support structure; a plunger assembly that again is a single unit with all of the required functionalities built in; a cartridge carriage unit that provides for orientation, retention, and positioning of the cartridge within the final assembled instrument; a support structure designed to position and stabilize all of the functional units of the instrument and which may assist in placement and movement functions of the instrument; a vacuum system; one or more motors to drive the positioning of the plunger and the cartridge, etc; and electronic components to control, monitor, and report on the various functions and measurements made by the instrument.
Most preferably, the assay cartridge can be manufactured as follows. The cartridge consists of the following molded pieces: the carousel, the pistons (one or more designs), the test surface holder (top), the waste reservoir holder (bottom), the sample receiving port, and an attachable hinged swab retention element (when required). The test surface holder has an opening and the optically active test surface is heat sealed to the bottom of the opening so that the optical surface is exposed through the opening. The optically active test surface is created by applying the optical coatings and other layers required for proper optical function and then coated with the appropriate analyte specific capture reagents before it is ready to attach to the test surface holder. The waste reservoir has positions for one or more adsorbent pads of highly adsorbent material to be placed within the wells in the floor of the part. These two pieces may be heat sealed, glued, or snapped together to provide the platform piece of the final assembled cartridge. The reagent carousel has the upper vapor seal applied by heat sealing the polyethylene layer of the vapor seal to the plastic carousel at a number of points, e.g., around each reagent well and at the edges of the carousel. The plastic pistons are loaded onto the reagent well and then the reagent well is filled with reagent. Then the lower vapor seal is then applied to the cartridge. The lower vapor seal has an opening that corresponds to the sample receiving port and a cutout that corresponds to the reading well. At the under side of the carousel and where the vapor seal has an opening one or more membranes (gradient membranes, single-pore size membranes, Memtex® membranes, etc.) are heat sealed to the under surface of the sample receiving port and then an adhesive, plastic gasket is applied over the membranes to assist in the establishing of vacuum during use. If the sample receiving feature is not an integral part of the mold then the element can feature a snap fit into position within the carousel. The carousel is then attached to the lower platform element of the cartridge. The entire cartridge may be wrapped in a vapor proof bag or may be placed in a kit as individual unwrapped units.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 depicts a top on view of a representative assay cartridge.
FIG. 2 a depicts the various components and their alignment for the reagent carousel portion of the assay cartridge from a top view.
FIG. 2 b depicts a top view of the base of the reagent carousel.
FIG. 3 depicts the various components and their alignment for the carousel portion of the assay cartridge from a bottom view.
FIG. 4 depicts an enlargement of a sealed reagent well within the reagent carousel and one possible piston design contained within the reagent well and the contact between the reagent well and reagent delivery port in the bottom section of the assay cartridge.
FIGS. 5 ( a-c ) depicts the reagent well within the reagent carousel and the piston action for reagent delivery.
FIG. 6 depicts a front view of an open instrument system.
FIG. 7 depicts the optical components and the anchor plate for those components.
FIG. 8 depicts a downward looking view of an open instrument system demonstrating cartridge placement and other key instrument features.
FIG. 9 depicts a side view of an open instrument system.
FIG. 10 depicts an elevated off angle view of an open instrument system.
FIG. 11 depicts a bottom view of an open instrument system.
FIG. 12 depicts a system flow chart for the power on process of the instrumented system.
FIG. 13 depicts a system flow chart for the temperature monitoring and computer system monitoring Daemon.
FIG. 14 depicts a system flow chart for the bar code monitoring Daemon.
FIG. 15 depicts a system flow chart for control lot verification.
FIG. 16 depicts a system flow chart for the cartridge mounting monitoring Daemon.
FIG. 17 depicts a system flow chart for the main process.
FIG. 18 depicts a system flow chart for start-up.
FIG. 19 depicts a system flow chart for the assay monitoring Daemon.
FIG. 20 depicts a system flow chart for the assay.
FIG. 21 depicts a system flow chart for the optical measurement.
FIG. 22 depicts a system flow chart for the cartridge unloading.
FIG. 23 depicts a system flow chart for instrument QC.
FIG. 24 depicts a system flow chart for data review.
FIG. 25 depicts a system flow chart for data uploading.
FIG. 26 depicts a system flow chart for set-up.
FIG. 27 depicts a system flow chart for diagnostics.
FIG. 28 depicts a system flow chart for main process; do-assay.
FIG. 29 depicts a system flow chart for main process; do-scan.
FIG. 30 depicts a system flow chart for start-up.
FIG. 31 depicts a system flow chart for assay.
FIG. 32 depicts a system flow chart for optical measurements.
FIG. 33 depicts a system flow chart for releasing extraction reagent.
FIG. 34 depicts a system flow chart for extracting the sample.
FIG. 35 depicts a system flow chart for adding reagent to the optically active surface or membrane.
FIG. 36 depicts a system flow chart for adding wash to the optically active surface or membrane.
FIG. 37 depicts a system flow chart for other sub-processes.
FIG. 38 depicts the highest-level data qualification/classification algorithm.
FIG. 39 depicts the data qualification/classification algorithm for the pre-scan qualification.
FIG. 40 depicts the data qualification/classification algorithm for the post-conjugate scan qualification.
FIG. 41 depicts the data qualification/classification algorithm for the post-substrate scan qualification.
FIG. 42 depicts the data qualification/classification algorithm for the form ratios and detect peaks.
FIG. 43 depicts the data qualification/classification algorithm for the storage and printing of results.
FIG. 44 depicts the data qualification/classification algorithm for the elimination of optical system over-scan from the data.
FIG. 45 depicts the data qualification/classification algorithm for the generation of pre-scan metrics.
FIG. 46 depicts the data qualification/classification algorithm for the qualification of the pre-scan metrics.
FIG. 47 depicts the data qualification/classification algorithm for the alignment of pre- and post-conjugate scan data.
FIG. 48 depicts the data qualification/classification algorithm for the generation of post-conjugate metrics.
FIG. 49 depicts the data qualification/classification algorithm for the qualification of post-conjugate metrics.
FIG. 50 depicts the data qualification/classification algorithm for the detection of peaks in the ratio data.
FIG. 51 depicts the data qualification/classification algorithm for the generation of post-conjugate metrics.
FIG. 52 depicts the data qualification/classification algorithm for the qualification of post-conjugate metrics.
FIG. 53 depicts an expanded view of an assembled reagent cartridge.
FIGS. 54 a - 54 d depicts one possible bottom configuration of the test cartridge.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The Assay Cartridge
FIG. 1 depicts an assembled test cartridge for use with the instrument of this invention. The assembled cartridge 2 includes an optical reading well 20 , a sample-processing element 6 , a reagent carousel 4 , and reagent wells 8 . In the depicted embodiment, the test cartridge also includes optional finger grips 16 , cartridge locking features 10 , and cartridge/instrument registration features 18 . Also in the depicted embodiment, the bottom member of the test cartridge is made of two separate molded pieces. Bottom section 12 is the bottom-most piece of the cartridge assembly, and is designed to accept and retain an absorbent material for the isolation of waste sample and reagents during the assay process. The upper section 14 of the bottom of the test cartridge contains the optical reading well and an aperture at the bottom of the optical reading well to allow the optically active test surface to be fused or otherwise attached to the bottom of the aperture. Preferred methods for attaching the test surface are heat sealing, heat staking, or an adhesive process. The complete test cartridge consists of a top member reagent carousel 4 , a sample-handling or processing element 6 , and the two pieces of the bottom section 12 and 14 . Optional finger grips 16 are extended ribs from the surface of parts 12 and 14 at the indented portion of the cartridge side walls. The indentation and the finger grips 16 are included to facilitate cartridge loading and handling by the user. When the optional carousel locking extender tabs 10 are in the up position, a locking mechanism engages the cartridge so that the cartridge is not free to rotate. When the cartridge 2 is in proper registration with the instrument, the tabs 10 are depressed and the carousel 4 is released and can be rotated. Rotation of the reagent carousel 4 allows the reagent wells 8 to be aligned in the proper sequence over the optical reading well 20 and the optically active test surface at the bottom of well 20 . Rotation of the reagent carousel 4 also allows the sample-processing device 6 to be aligned over the optical reading well 20 and thus the optically active surface at the proper time.
The Reagent Carousel
FIG. 2 a depicts an exploded view of the reagent carousel 2 . An optional cartridge label 22 is designed to carry all of the assay specific information and identification and the lower surface is an adhesive surface that assists in the sealing of reagent wells 8 . A hard plastic (e.g., polystyrene) piston 24 is placed in each reagent well 8 during the filling and construction of the reagent carousel 4 . The piston 24 is preferably designed to assist in the sealing of the upper opening of the reagent well 8 and in the delivery of reagent to the optically active test surface. In the depicted embodiment, piston 24 has a flat surface that is sealed to label 22 while label 22 also seals to the walls of the reagent wells 8 . The skilled artisan will recognize that other methods of sealing the reagent wells may also be employed. For example, an individual seal or moisture barrier may be used to seal the upper opening of each reagent well. In FIG. 2, the sample handling or processing device 6 consists of a series of fingers 30 designed to secure a swab of specific dimensions or fiber bundle size. The sample-processing device 6 is complementary to the type of device (e.g., a swab) on which a sample is to be introduced into the cartridge 2 and/or for the analytical test to be performed by the cartridge 2 in the instrumented assay system. In preferred embodiments, the sample processing device 6 is secured within the reagent carousel 4 by pressure, or physical interference, or a snap fit mechanism, or is molded as part of the reagent carousel. A bottom reagent seal 26 is used to seal the bottom of the reagent well. Preferably, the reagent seal 26 is a mylar type film that is adhered to the molded plastic part 28 prior to the introduction of a liquid reagent to the reagent wells 8 when the reagent well is filled from the top. If the reagent well is filled from the bottom, the label 22 is applied first and label 26 is applied after filling. Preferably, the reagent wells 8 can contain between about 100 to about 600 μl of reagent, however, the volume of the reagent wells are to be determined by the artisan, based on the intended application. The reagent wells 8 can be configured within the molded part 28 to be of varying internal diameter to accommodate the varying volume of a specific reagent. Those skilled in the art will recognized that other c configurations of the reagent well may be employed. For example, the molded plastic part 28 may be formed such that the reagent well 8 protrudes downward from a flat upper top. The protrusion of the well downward wherein the bottom of the well does not extend below the bottom of the molded plastic part 28 . A configuration such as this allows the piston 24 to be pushed down into the reagent well 8 without the need for returning it to an upper position due to exposure and drag in the instrument. The piston size 24 and the volume of air that it displaces in the reagent well 8 can also be used to control the fill volume in the reagent well 8 . The filling process will dispense a pre-set volume of each reagent to the appropriate well 8 . The reagent seal 26 contains an opening that is positioned under the sample-processing device 6 to allow for flow of the processed sample to the optically active test surface. A vacuum gasket 32 is optionally sealed by adhesive to the reagent seal 26 below the sample-processing aperture. This is to improve the registration of the reagent carousel 4 with the cartridge 2 when the sample processing device 6 is aligned with optical reading well 20 and vacuum is applied from below the optically active test surface. In certain embodiments, processed sample is delivered to the optically active test surface when vacuum is applied to the cartridge 2 . In these embodiments, vacuum is used to provide flow when the processed sample would not readily flow into contact with the optically active test surface. Preferably, part numbers 6 and 28 of reagent carousel 4 (see FIG. 2) are made of polypropylene or polyethylene, and part numbers 12 and 14 of the cartridge are made of polystyrene. However, one skilled in the art will recognize that other materials can provide similar structural characteristics.
FIG. 2 b depicts the base 28 of the depicted embodiment of the reagent carousel 4 . Also visible are reagent wells 8 . The opening 34 allows the cartridge rotation element 96 to seat in the reagent carousel 4 for proper registration and rotation of the reagent carousel during the assay procedure. Opening 36 is designed to accept a variety of sample-processing modules 6 . Preferably, the reagent seal 26 is applied to the reagent wells 8 by a heat staking process.
FIG. 3 depicts a bottom view of the depicted embodiment of the reagent carousel 4 . The features visible from this view include an extraction reagent flow channel 38 and a differential seal 34 designed to control the flow of extraction reagent(s) into the sample-processing device 6 . In certain embodiments, a flat piston (not pictured) applies pressure to break the weak reagent seal 34 and allow flow to occur within reagent channel 38 . As the piston is displaced downward the extraction reagent is driven through the channel 38 and up the continuation of channel 38 to a well contained within the sample-processing feature 6 . In these embodiments, the positive displacement of the piston generates sufficient pressure to move the extraction reagent up and into the sample-processing feature. Thus the extraction reagent or diluent flows into the sample-processing device and contacts the sample collection device or added sample. In embodiments which utilize vacuum to facilitate sample flow, application of vacuum releases the analyte of interest from the sample collection device to the test surface.
FIG. 4 depicts an cross sectional view of a reagent well 8 in preferred embodiment of the final assembled reagent carousel 4 . Label 22 is designed so that the upper portion of piston 24 is also sealed with label 22 . Thus, the label 22 contacts the piston 24 and the top of the reagent wells 8 to provide a multi-component seal. The piston 24 includes an optional hex boss feature 40 designed to mate with the instrument plunger mechanism and has a pointed end structure. FIG. 4 shows the reagent well 8 positioned over the optical reading well 20 and shows a cross sectional view of the optical read well 20 side walls 42 . The side walls 42 are preferably designed to provide an uninterrupted optical pathway and to accommodate the reagent volumes to be applied to the optically active test surface. An optional gasket may be placed between the reagent carousel 4 and the upper portion 14 of the bottom section of the cartridge 2 .
FIGS. 5, a-c, depicts a preferred displacement process for the piston 24 to deliver reagent to the surface of an optically active test surface. In this embodiment, a push rod 46 is attached to a vertical drive element 44 (FIG. 5 b ). The end of push rod 46 is designed to seat within the optional hex boss 40 of the piston 24 . When the piston does not include a hex boss feature the push rod may simply contact the piston to drive it. As in FIG. 5 b the vertical drive element 44 then drives the push rod 46 and the piston 24 downward and piston 24 will pierce the seal 26 and release the reagent from the reagent well 8 . Push rod 46 may also pierce label 22 prior to contact with the piston 24 . The downward force exerted by the vertical drive element 44 and the push rod 46 is sufficient to break the seal of the upper flat structure of piston 24 from the seal 22 . For the preferred seal material described herein, approximately 5-7 pounds of force is required. The skilled artisan can easily determine the necessary force for breaking other sealing materials. Once the seal 26 is pierced the reagent preferably flows down the side walls 42 of the optical reading well 20 and into contact with the optically active test surface. The vertical drive element 44 and the push rod 46 then optionally pull the piston 24 back to its original position within the reagent well 8 to prevent the piston 24 from restricting rotation of the cartridge 2 (FIG. 5 c ). The retraction mechanism may not be required if the hex boss is not included in the piston or it is not required to return the piston to an original position.
FIG. 53 depicts an exploded view of the depicted embodiment of the assembled cartridge, consisting of the cartridge bottom of FIGS. 54 a-d with the reagent carousel 4 of FIG. 1 . When the sample type to be analyzed is a fluid from which an analyte containing particulate is to be removed, the bottom of sample-processing feature 36 preferably consists of an optional membrane material designed to retain the particulate and remove the excess sample fluid. If required, vacuum is applied to 36 after the fluid sample is applied and port 36 is aligned with 136 so that fluid flows into adsorbent 140 . An extraction reagent can be applied to the membrane in 36 , such that the analyte is removed from the particulate matrix. In the depicted embodiment, when 36 is aligned over the optically active test surface 132 and vacuum is applied, the extracted analyte flows through the membrane at the bottom of 36 and through the filter unit 130 and onto the optically active surface 132 . If the sample processing feature 36 is designed for use with a non-fluid sample, or the analyte is not particulate associated, the membrane sealed to the bottom of 36 may not be required. Piston 122 is the piston used to deliver extraction reagent as described herein.
FIG. 54 a depicts a preferred configuration of the assay cartridge bottom 152 , where part 152 replaces part 12 and part 14 of the assay cartridge shown in FIG. 1 . Extension 34 mates with the corresponding opening 34 in the reagent carousel 28 and matches the part 120 of the instrument to drive the rotation of the reagent carousel. This cartridge configuration includes an optional grip position 138 that may support surface extensions to improve the manual grip of the assay cartridge. Opening 136 allows a fluid sample such as urine to be directed to the adsorbent waste pad 140 seen in FIG. 53 . Opening 132 provides access to the optically active test surface. The optically active test surface is attached to the bottom of part 152 at position 132 . Opening 154 is a vacuum port. FIG. 54 b depicts the bottom view of the preferred configuration of the assay cartridge bottom 152 .
FIG. 54 c depicts the bottom view of a preferred configuration of a cartridge bottom-housing portion 156 of the assay cartridge 2 . The bottom-housing portion 156 has an optional grip portion 142 that aligns with optional grip 138 in the assembled assay cartridge. Opening 34 aligns with the opening 34 of the cartridge bottom 152 as part of the assay cartridge rotation mechanism. Raised section 144 of the vacuum housing portion 156 is used to provide a mechanical seating of the cartridge within the instrument. FIG. 54 d shows the upper view of a preferred configuration of vacuum housing portion 156 . Wells 146 and 148 preferably retain the adsorbent materials 150 and 140 shown in FIG. 53 .
The Analytical Instrument
FIG. 6 depicts a front view of a preferred embodiment of instrument system 84 . In this embodiment, the instrument is supported on a platform supported by legs 74 . Preferably, the instrument comprises an optical detection portion that consists of parts 66 , 64 , 68 , 62 , 70 , and optional retention brackets 50 . The brackets 50 can be used to stabilize the placement of key instrument components. Part 66 is an optional solid plate designed to attach to instrument back support 80 and casing support 58 and to align the components of the optical detection portion of the instrument. In this preferred embodiment, the optical detection portion consists of a light source 62 and a fixed polarizing element 70 . In addition the optical detection portion consists of a detector 64 and a fixed analyzing polarizing element 68 . The v-block structure of 66 provides the angle control or a fixed angle position for the optical detection portion of the instrument. An optical encoder 78 is used to assist in the optical scanning of the surface. The skilled artisan will recognize that the instrument design can be modified to use alternative detector types, as described herein. For example, the described optical detection portion may be replaced by a fluorimeter, spectrophotometer, etc.
A plunger, or vertical drive, element 44 is preferably attached to linear motor 48 . A push rod 46 can be attached to the vertical drive element 44 . Another element of this embodiment of a total vertical or linear drive assembly is an optional presser foot 52 . The presser foot 52 provides downward pressure on the cartridge 2 to align and stabilize the cartridge 2 . The presser foot may not be required if a lock and key mechanical registration method is used to secure the cartridge within the instrument.
In the depicted embodiment, the cartridge positioning assembly includes an optional loading door 54 that is attached to rails that are anchored to loading door 54 by retention rings 60 . Cartridge rails 76 can be used to horizontally align and place the assay cartridge 2 within the proper position for the optical detection portion and the vertical drive assembly for reagent release and optical analysis. In this embodiment a latch 56 is used to secure optional loading door 54 , but the skilled artisan will recognize that other mechanisms can be utilized. All or some of the depicted features may be preferably eliminated, for example if a locking-type or pin set mechanism is used for cartridge retention and stability, and the optimal design is left to the artisan, based upon the requirements of the selected cartridge format, detector type, etc. With such a pin set mechanism, relying on two set pins and the rotation element 96 for cartridge retention, part numbers 52 , 76 , 54 , 60 , 88 , 90 , 92 , 94 , and 54 are eliminated. The cartridge rails 76 can be replaced by a single extruded sliding support on each side of the instrument. The cartridge receiving stage is attached to brackets that are capable of sliding and the brackets are slidably attached to the side supports.
Optional sensor 104 detects when the optional vacuum engagement mechanism 72 is aligned to apply vacuum to the assay cartridge 2 . In certain embodiments, the vacuum engagement mechanism 72 displaces the vacuum from engagement with the bottom of the instrument to allow cartridge rotation and cartridge loading and unloading. The sensor 104 and the vacuum engagement mechanism 72 may be replaced when the cartridge receiving mechanism is sufficient to align and stabilize the cartridge in the absence of vacuum. In preferred embodiments, the stage is attached by brackets to the extruded side supports, and the cartridge is pressed down as it is brought into the interior of the instrument from the cartridge loading door. As the cartridge is lowered on to the receiving stage it contacts an optional vacuum mat that serves to provide a vacuum seal when vacuum is applied to the cartridge.
FIG. 7 depicts an enlarged view of a preferred optical detection portion of the instrument 84 . The v-block structure 66 is clearly visible and provides for proper optical alignment. The v-block structure is preferably made of machined or cast metal construction to provide the stability that the optical alignment requires. Other similar materials known to the artisan can provide similar stability. Various mounting holes 86 are shown within the v-block structure 66 .
FIG. 8 shows a top view of the depicted embodiment of instrument 84 . Optional features demonstrated in this view are the alignment springs 94 that provide alignment and stability for the cartridge 2 once secured in the cartridge delivery assembly. The optional presser foot 52 that assists in cartridge positioning is also more clearly visible. In preferred embodiments springs 92 also assist in the alignment and stability of the cartridge 2 .
In certain preferred embodiments, the cartridge 2 is freed to rotate by contact of optional pressure feet 90 with the optional tabs 10 on the cartridge 2 . Additionally, alignment and stability can be provided by locking feet 88 . The cartridge delivery assembly rails 76 are also shown. In the depicted embodiment, the cartridge 2 is displaced from the front of the instrument where it is loaded to the proper position for analysis. Optional cartridge loading door 54 also provides stability and alignment of cartridge 2 . Rotation drive element 96 preferably seats in the center of cartridge 2 and assists in the rotation of the reagent carousel 4 to the appropriate position as the assay procedure is conducted. As noted above some or all of these elements may be replaced or eliminated depending on the mechanism used to retain and position the cartridge.
FIG. 9 depicts a side view of the depicted embodiment of instrument 84 . Features visible in this view include an optional cartridge positioning assembly side wall 102 . In preferred embodiments, the side walls help retain and align the cartridge 2 as it is moved into proper alignment for the assay procedure to be conducted and the optical analysis completed. In this view the optional vacuum engagement element 72 is in the engaged position such that vacuum is applied in the proper sequence and positions. Optional optical sensor 104 is involved in control of the cartridge 2 rotation. In the depicted embodiment a translation screw 98 is attached to motor rail 100 , providing for the movement of the cartridge 2 into and out of the instrument detection path and processing elements. In certain preferred embodiments, the two separate pieces numbered 102 may become one single extruded side support when the cartridge platform is attached to brackets that are capable of sliding and the brackets are slidably attached to the side support. The slide can allow for proper positioning of the cartridge within the instrument.
FIG. 10 depicts an oblique view of the depicted embodiment of instrument 84 . In this view the optional presser foot 52 is raised from the contact with cartridge 2 so that motor 106 is visible. In this preferred embodiment, motor 106 moves the optional vacuum engagement mechanism 72 into and out of contact with the bottom of instrument 84 . Thus motor 106 assists in the activation and removal of vacuum during the assay procedure. An optional latching mechanism 56 is also more visible. As noted previously, any other mechanism that can be used to secure the loading door 54 once a cartridge 2 is loaded into the cartridge delivery track can be used or may not be necessary if a different mechanical registration mechanism is used for the cartridge. Optional optical sensor 110 is used to sense when the cartridge is properly positioned under the optical detection portion and relative to the piston drive elements. In preferred embodiments, rails 108 serve to seal the cartridge loading door 54 against the cartridge 2 and provide secure cartridge alignment. These optional rails 108 may be driven by motor 106 or may have an independent motor controlling their translocation. Optical sensor 112 senses when the cartridge loading door 54 is in the home or initial position. Motor 106 may be eliminated if the vacuum system engagement features is addressed by the cartridge positioning and a vacuum mat system.
FIG. 11 depicts the depicted embodiment of instrument 84 in a bottom view. Features visible in this view include a carousel rotation motor 114 and vacuum connectors 116 . The optional vacuum connectors feed into pliable plastic gaskets or suction cups that assist in creating the vacuum seal to the appropriate cartridge features. In this preferred embodiment, drive belt 118 works with rotation motor 114 to rotate the cartridge. Also visible is the bottom section of rotation drive element 120 that is in contact with drive belt 118 . Other mechanisms to rotate and/or index the cartridge can be used in place of the motor and drive belt of the depicted embodiment. The choice of a suitable rotation mechanism is preferably left to the skilled artisan, and can be appropriate to the cartridge design.
Instrument Control Algorithms
FIGS. 12-54 depict various system flow charts for preferred power-on processes to a final data analysis. The design of the instrument provides sufficient flexibility for the skilled artisan to design appropriate control algorithms for a particular assay. One skilled in the art will recognize that not all of the depicted flow charts, or the various portions thereof, will be required for a given assay or instrument design. The skilled artesian will also recognize that the depicted flow charts, or various portions thereof, may be combined into one function, or split into multiple functions, dependent upon the needs of a given protocol, assay, or instrument.
FIG. 12 depicts a preferred control algorithm used for the system power-on process. The depicted control algorithm indicates the various control points during a preferred start-up procedure where an out of specification reading can lead to failure to complete the start-up procedure and where action by the user may be required. For example, control points 1 - 4 are found in FIGS. 13 a, 14 , 16 , 13 b, respectively. Control point 1 determines that the system's ambient temperature is in the proper range for optimal assay performance before an analysis can be performed (FIG. 13 a ). In certain embodiments this control point may include feedback control over a heating an/or cooling unit designed to maintain the system's temperature at the requirements of a given assay. Those skilled in the art will recognize assay temperature requirements comprising an assay or protocol for a given system. Control point 2 determines that the barcode reader function (when included) can properly identify the barcode information on the kit box, the assay cartridge, and/or the specimen. If there is a failure in the barcode, cycle user intervention may be required (FIG. 14 ). Control point 3 determines that the cartridge is present and that the cartridge information is adequate to begin the assay procedure (FIG. 16 ). Control point 3 has its own control point 6 (FIG. 17 ). This control point determines that all requirements are met and the assay procedure can be started. Control point 4 (FIG. 13 b ) establishes that the system memory is performing to specifications. If a bar code reader is not included in the instrumented system then an alternate verification scheme would be designed into the system software to confirm the availability of the proper control information.
FIG. 15 depicts a preferred algorithm used to verify the lot information. FIG. 18 depicts a preferred system start up algorithm. The process insures that the assay cartridge is registered in the instrument correctly, that the cartridge has not been previously used, that the cartridge is within expiration dating, that the vacuum pump is on, and that the appropriate level of vacuum has been reached and that the optics are functioning correctly. Control point 7 (FIG. 19) determines that the vacuum level is within specification and the optical signal is within specification. Optics may also be monitored as a part of the startup daemon.
FIG. 20 depicts a preferred control algorithm for the assay procedure. In preferred embodiments, this algorithm is controls the highest level requirements for the assay procedure. Preferably, the algorithm insures that all of the components for the assay procedure are in place and within specification and controls the indexing of the assay cartridge to the proper processing positions for the selected assay procedure. It also provides for data output at the conclusion of the assay procedure. The algorithm has an internal control loop that must be satisfied for the assay to proceed. The control loop verifies that all required inputs have been entered or received. One skilled in the art will recognize that the control algorithm will depend on the steps required to perform a given assay.
FIG. 21 depicts a preferred control algorithm for an optical measurement procedure. In certain embodiments, this algorithm controls the scanning of the reacted optically active test surface, the number of measurements made during the scan, and data storage. FIG. 22 depicts a preferred control algorithm for the unloading of a reacted assay cartridge and the return to the start position. In preferred embodiments, control point 5 allows the instrument to verify that an assay cartridge has been removed from the instrument, and returns the instrument to “ready” mode for insertion of a new assay cartridge. FIG. 23 depicts a preferred control algorithm for a QC process. Beyond identifying the run as a QC run the remaining protocol is the same as for a test sample.
FIG. 24 depicts a preferred control algorithm for data review and the appropriate control points and control procedures. The appropriate processing function is selected based on the user choice of specimen identification, user identification, date, analyte, or cartridge designation. The control point 8 (FIG. 24 b ) allows data review by a specific specimen identification. Control point 9 (FIG. 24 c ) allows data to be reviewed by a specific operator identification. Control point 10 (FIG. 24 d ) allows data to be reviewed by a selected data set or range. Control point 11 (FIG. 24 e ) allows data to be reviewed by a specific analyte and control point 12 (FIG. 24 f ) allows data to be reviewed by a specific cartridge lot number. FIG. 25 depicts the control procedure for uploading data processing to a LIS or HIS. Data can be deleted upon uploading, or in an added separate function.
FIG. 26 depicts a preferred set-up control algorithm for an entire assay procedure. FIG. 26 a is the highest level control chart and identifies control points 13 - 26 . Control point 13 prompts the user to set a time and time format. Control point 14 prompts the user to set a date and date format. Control point 15 prompts the user to set a reporting language. Control point 16 (FIG. 26 b ) verifies that an operator identification was prompted for and entered or that a default identification was selected. Control point 17 (FIG. 26 c ) verifies that a specimen identification was prompted for and entered. Control point 18 (FIG. 26 d ) verifies that a QC specimen must be run if the user selects a new shift, new day, or new operator. Once the QC parameter is selected in the instrument set-up routine, the instrument will not allow any patient tests to be assayed until a QC specimen is ran when the QC parameter is changed. Control point 19 (FIG. 26 e ) verifies that the instrument identification is included in the report output generated. Control point 20 (FIG. 26 f ) verifies that the user has set an appropriate sound level for the system bells. Control point 21 (FIG. 26 g ) prompts the user to enter an appropriate report header. Control point 22 (FIG. 26 h ) prompts the user to enter the number of reports required for a single assay result. Control point 23 prompts the user to enter the data format for upload to LIS or HIS. Control point 24 prompts the user to set parameters for serial port connection to LIS or HIS. Control point 24 can also be present during instrument manufacture, and thus will not be required as a separate control point in the assay software. Control point 25 (FIG. 26 i ) provides the user the option of including graded or semi-quantitative results on a report in addition to a qualitative result. Control point 26 provides the user the option of using either a “+” or a“?” symbology on the report to represent an indeterminate result.
FIG. 27 depicts a preferred diagnostic processes for the various components of the instrument and their relation to the various assay procedures. Process flows 27 - 32 are not unique to every assay cartridge and assay procedure but are the highest level control processes required to assure that the various instrument components are active and within specification. These process flows may introduce a feedback loop into the self-check algorithms for monitoring purposes.
FIG. 28 depicts preferred general assay procedure requirements in the sequence required to produce a final result. FIG. 29 depicts the general sequence required to complete the optical scanning process and the cartridge handling required to allow for the optical scanning procedure. FIG. 30 depicts the general sequence required for the vacuum control in the assay procedure. FIG. 31 depicts a general assay sequence of processing requirements. This protocol may accommodate a number of different analyte-specific testing protocols. However, the number and sequence of the processing steps may be adjusted to accommodate any analyte-specific test protocol. FIG. 32 depicts the processing sequence for the optical reading of the optically active test surface within the assay cartridge. FIG. 33 depicts one possible extraction reagent addition sequence. FIG. 34 completes one possible extraction sequence for an analyte-specific testing protocol. FIG. 35 depicts the sequence of processing steps required for reagent addition to an optically active test surface or membrane. This is one possible sequence of processing steps that is dependent on the analyte-specific test being performed. This protocol may be applicable to a number of analyte-specific tests.
FIG. 36 depicts one possible sequence for a wash cycle on the optically active test surface or membrane. The wash cycles within a single assay procedure and between analyte-specific testing procedures may differ in a number of parameters. These parameters include the time wash is allowed to contact the surface prior to application of vacuum, the use of an air flow over the surface to facilitate drying of the test surface, the vacuum pulse times and pressure. Other parameters include the pressure level maintained and the time that level is maintained, etc. Drying of the test surface may be related to the vacuum pressure. The same level of drying may not be required following each wash step and the same level of drying may not be required for different types of test surfaces. When an optically active test surface is to be optically scanned the surface must be dry. FIG. 37 depicts the vacuum level considerations and procedures.
FIG. 38 depicts one possible method for qualifying optical data as it is collected during the assay procedure. Data is qualified as it is collected and if at any point the data fails to meet the qualification requirements the analysis is terminated at that point. FIG. 39 depicts the first level of optical data qualification, applying metrics to the pre-assay procedure, optical scan. FIG. 40 depicts another level of optical data qualification. In this case the metrics are applied to a scan completed after the addition of an amplifying reagent to the optically active test surface. The amplifying reagent consists of an antibody and enzyme conjugate. The optical scan is conducted after a wash cycle is completed to remove any unbound amplifying reagent. One of the metrics applied must verify that the alignment of the optical scan being qualified matches the alignment of any previous scans to account for any surface variability that is not related to the assay result. The number of qualifications of optical data and optical scans and the metric applied will vary with the type of test surface under analysis. FIG. 41 depicts the same type of qualification as shown in FIG. 40 . But the qualification is conducted after a precipitating substrate was been allowed to react with the amplifying reagent. FIG. 42 depicts one possible data processing mechanism. In this case the qualified optical scans are used to produce a ratio of the scan data. The peak ratio data is reported as a final result. FIG. 43 represents the steps required to store and report results. The storage table should allow all critical assay information to be stored. FIG. 44 depicts a method that can be used to eliminate optical overscan from the data set. Any number of normalization routines may be used to correct for the overscan in the data. A Savitsky-Golay polynomial can be used. Once the proper coefficients and polynomials are established for a particular assay cartridge the information is hard coded into the program. The noise cut-off for a particular assay system can be empirically determined and again hard coded into the program. FIG. 45 depicts one possible pre-scan metric analysis, while FIG. 46 depicts the qualification of those metrics. FIG. 47 depicts the process used for the alignment of the pre-and post-conjugate scans. This process is specific to one type of analyte-specific testing protocol and assay cartridge. However, similar considerations may apply to other assay systems. FIG. 48 depicts one method for the generation of metrics in one type of assay protocol, while FIG. 49 qualifies the same metrics. When the analyte capture portion of the test surface within the cartridge is created by applying the capture reagent in lines along the test surface, edge detection and peak detection in the optical scan will be a critical part of the data analysis. FIG. 50 represents one such approach to address these issues. FIG. 51 depicts a process to create the post-conjugate metrics, while FIG. 52 qualifies the metrics. Control algorithms also exist for the quality control requirements, adjusting or setting the time and date, instrument alarm and notification features, report language, instrument self-diagnostics, number of reports generated, etc.
Analyte Detection
Preferred analyte detection methods utilize an optically active test surface in conjunction with an ellipsometric detection method as described herein. One skilled in the art will understand that the methods described herein can be adapted to other test surfaces and detection methods. In certain preferred embodiments, an optically active test surface includes the following components: a support material, one or more optically functional layers, an optional attachment layer, an analyte-specific receptive material, and an optional protective overcoat. Preferably, the optically active test surface is designed to exploit thin film interactions with light. Attenuation of light incident on the optically active test surface is related to the changes in optical film thickness due to analyte binding to the optically active test surface.
In preferred embodiments, a representative support material would be a track etched polycarbonate membrane with a pore density of less than 15% of the total surface area. Other appropriate support materials are polyester, nylon, cellulose acetate, woven and non-woven materials, polysulfones, polypropylenes, and polyurethanes. Other porous or non-porous materials may be utilized. Non-porous materials would require adaptation of the cartridge 1 to permit fluid flow around the test surface under vacuum and the surface must not break or crack under vacuum. The support must be capable of being processed by the procedures used to deposit the optically functional layers and all subsequent processing steps. The support need not have the optical properties desired in the final optically active test surface as the subsequent coatings can supply the proper optical characteristics. The support should be chemically inert to all the chemicals and solvents used in subsequent processing steps. All subsequent layers should maintain the porosity of the original support.
Preferably, the analyte-specific receptive layer is a material or materials that have sufficient affinity and specificity to bind the analyte of interest to the surface of the optically active test device. This allows for detection of the analyte of interest. Once the analyte-specific receptive layer is coated onto the optically active test surface, an overcoat layer may be applied to increase the long term stability of the optically active test device. Representative analyte-specific receptive layers include antigens, antibodies, lipopolysaccharides, polysaccharides, microorganisms, food contaminants, environmental agents, allergens, nucleic acids, DNA, RNA, pesticides, ligands, receptors, chelates, proteins, enzymes, herbicides, inorganic or organic compounds or fragments or analogs thereof. The analyte-specific receptive material may be applied to surface by solution coating, spray coating, spot coating, ink jetting, air brushing, or other processes known to those skilled in the art. The analyte-specific binding material can be applied as a stripe, or a spot, or other appropriate geometric design. The analyte-specific binding material should be applied in a specific, reproducible pattern to facilitate optical reading of the reacted surface.
In addition to an analyte-specific binding material, the test surface may be coated with one or more control materials. These control materials can be used to assist in the verification that the proper assay sequence was performed and that the assay reagents were functioning as anticipated. In other preferred embodiments, more than one analyte-specific binding material can be applied to the test surface. The number of analyte-specific binding materials applied is limited only by the ability to resolve the individual reaction zones with the detection method employed.
Preferred analytes may include antigens, antibodies, lipopolysaccharides, polysaccharides, microorganisms, food contaminants, environmental agents, allergens, nucleic acids, DNA, RNA, pesticides, ligands, receptors, chelates, proteins, enzymes, herbicides, inorganic or organic compounds or fragments or analogs thereof.
The assay system may be applied to a wide range of different analytical testing applications. The assay cartridge components determine what analyte is being detected and the instrument analyzes the reactions on the test surface in the cartridge and reports a result. The assay cartridge can be used in the detection of an infectious disease from a patient specimen where the specimen may be a throat swab, a nasal swab, a nasal wash, urine, blood, serum, plasma, a wound swab, a vaginal swab, a urethral swab, a endocervical swab, or other appropriate body fluid or collection swab. The assay cartridge can be used to detect other medical conditions from similar specimen types. The assay cartridge can be used to detect a specific component of a manufacturing process's waste. The assay cartridge can be used to detect the presence of an undesirable component in a food. The assay cartridge can be designed to detect a material for which there exists a specific binding agent.
In certain embodiments, an amplifying reagent may be used to increase the thin film effect of analyte binding to the thin film test surface (i.e., the optically active test surface) and is most preferably an enzyme-labeled antibody. For example, an insoluble reaction product results when an immobilized antibody-antigen-antibody-enzyme complex is present on the test surface. A reaction product is catalytically precipitated by the action of the enzyme on a precipitating agent in solution. Precipitating agents include combinations of alginic acid, dextran sulfate, methyl vinyl ether/maleic anhydride copolymer, or carrageenan and the like, as well as the product formed by the interaction of TMB (3,3′,5,5′-tetra-methyl-benzidine) with an oxygen free radical. This particular precipitating agent forms an insoluble product whenever a free radical contacts the TMB. Other substances including 4-chloronapthol, diaminobenzidene tetrahydrochloride, aminoethyl-carbazole, orthophenylenediamine and the like can also be used as precipitating agents. The precipitating agent is typically used in concentrations ranging from about 10 mM to 100 mM. But any material that can be attached to an analyte-specific binding reagent and can serve to increase the optical thickness of the analyte layer can be utilized.
Most preferably, the optical detection system used in the instrument is a thin film analyzer described in U.S. Pat. Nos. 5,494,829 and 5,631,171 and these references are hereby incorporated in their entirety. The thin film analyzer is designed to detect a change in the degree of polarization of light incident upon the optically active test surface. A change in the thin film due to analyte binding results in an attenuation of the light due to a further change in the degree of polarization of the light. The light is phase delayed by reflection through the thin films. The optical detection system is simple and inexpensive. The system includes a light source, two polarizers, and a detector. Preferably the light source is monochromatic. The detector is a silicon diode. The first polarizer in the system is used to provide incident light that is linearly polarized. The second polarizer or analyzer is set to select the change in polarization of the reflected light that is due to the presence of analyte binding. In other words the analyzer is set to minimize the signal to the detector when light is reflected from an unreacted optically active test surface.
In other preferred embodiments, the test surface may also be an unmodified polycarbonate support. In this case the test surface is preferably coated with the analyte-specific binding reagent and the signal generation is due to a reagent that binds the immobilized analyte and carries with it a chromophore, fluorophore, or the like to assist in detection. Construction of the test surface would be very similar to the considerations applied to the optically active test surface without the intervening optical layers. However, application of the analyte-specific binding reagent would use very similar methods. Assembly and use of the cartridge may or may not be different than when an optically active surface is utilized. It is preferably left to the skill of the artisan to determine the appropriate cartridge design and methods to be employed, according to the specific requirements to be met by the assay to be performed.
While the invention has been described and exemplified in sufficient detail for those skilled in this art to make and use it, various alternatives, modifications, and improvements should be apparent without departing from the spirit and scope of the invention.
One skilled in the art readily appreciates that the present invention is well adapted to carry out the objects and obtain the ends and advantages mentioned, as well as those inherent therein. The cell lines, embryos, animals, and processes and methods for producing them are representative of preferred embodiments, are exemplary, and are not intended as limitations on the scope of the invention. Modifications therein and other uses will occur to those skilled in the art. These modifications are encompassed within the spirit of the invention and are defined by the scope of the claims.
It will be readily apparent to a person skilled in the art that varying substitutions and modifications may be made to the invention disclosed herein without departing from the scope and spirit of the invention.
All patents and publications mentioned in the specification are indicative of the levels of those of ordinary skill in the art to which the invention pertains. All patents and publications are herein incorporated by reference to the same extent as if each individual publication was specifically and individually indicated to be incorporated by reference.
The invention illustratively described herein suitably may be practiced in the absence of any element or elements, limitation or limitations which is not specifically disclosed herein. Thus, for example, in each instance herein any of the terms “comprising”, “consisting essentially of” and “consisting of” may be replaced with either of the other two terms. The terms and expressions which have been employed are used as terms of description and not of limitation, and there is no intention that in the use of such terms and expressions of excluding any equivalents of the features shown and described or portions thereof, but it is recognized that various modifications are possible within the scope of the invention claimed. Thus, it should be understood that although the present invention has been specifically disclosed by preferred embodiments and optional features, modification and variation of the concepts herein disclosed may be resorted to by those skilled in the art, and that such modifications and variations are considered to be within the scope of this invention as defined by the appended claims.
In addition, where features or aspects of the invention are described in terms of Markush groups, those skilled in the art will recognize that the invention is also thereby described in terms of any individual member or subgroup of members of the Markush group. For example, if X is described as selected from the group consisting of bromine, chlorine, and iodine, claims for X being bromine and claims for X being bromine and chlorine are fully described.
Other embodiments are set forth within the following claims. | The present invention relates to cost effective analytical instruments for determining the presence or amount of an analyte in a sample. The analytical instruments utilize an assay cartridge which has a sample receiving port and a rotatable carousel containing a plurality of reagent wells. Each reagent well includes a piston element for delivery of reagent to a test surface. The instrument is capable of indexing the assay cartridge to deliver sample and reagents to a test surface in a predetermined and flexibile manner, thus providing an assay protocol which is specific to the type of sample under analysis. The invention also relates to components, features, disposables, reagent delivery systems, accessories, and methods for using such instruments. Appropriate applications include infectious disease testing, cancer detection and monitoring, therapeutic drug level monitoring, allergy testing, environmental testing, food testing, diagnostic testing of human and veterinary samples, and off-line process testing. | 1 |
FIELD OF THE INVENTION
The present invention relates to slip coatings for the foil layer of an innerwrap material for cigarette packages and more particularly to a polyvinyl alcohol (PVOH) slip coating.
BACKGROUND OF THE INVENTION
In cigarette packaging, it is conventional to wrap the bundle of cigarettes of a package in a sheet material known as an “innerwrap” which almost always includes a layer of paper for strength, a layer of metal foil to inhibit loss of moisture content of the cigarettes, and an adhesive to bond the foil and paper into a single sheet or laminate. The thus-wrapped cigarettes are then placed in a soft pack or a paperboard box, as the case may be, and overwrapped with a clear plastic sheet material, such as a polypropylene or polyethylene terephthalate film.
The innerwrap sheet material is typically made on laminating machines and wound up into large rolls for subsequent use. In the cigarette packaging plant, the innerwrap is unrolled, cut, and wrapped about bundles of cigarettes to be packaged in individual packs.
It is also conventional in cigarette making to make cigarettes flavored with menthol or other flavorants. In the case of a menthol flavorant, menthol can be sprayed onto or otherwise added to shredded tobacco and cigarettes can then be made from the mentholated shredded tobacco in the usual way. This is a practical method for manufacturing large quantities of menthol cigarettes in machines dedicated to producing only menthol cigarettes, but is impractical in the case of cigarette making machines, e.g., in smaller manufacturing plants, which may be used to manufacture non-flavored cigarettes as well as mentholated cigarettes. In such plants, the mentholated tobacco permeates the cigarette manufacturing equipment with the menthol flavorant which is difficult to remove from the equipment, so that an unintended menthol scent and/or taste is imparted to cigarettes subsequently made on the same equipment, even when regular, unflavored tobacco is used.
To avoid the problem of menthol-tainted machinery and to provide a way to permit cigarette manufacturing plants to make both flavored and non-flavored cigarettes on the same machinery, it is more advantageous to incorporate the menthol or other flavorant into the paper on the inner side of the innerwrap. Since menthol has a high vapor pressure, after a bundle of cigarettes is wrapped in a completed package, the menthol will diffuse into the tobacco of the cigarettes wrapped inside the innerwrap envelope, thereby imparting the desired menthol taste and aroma to the cigarettes. Typically, menthol is applied to the innerwrap at a location other than at the cigarette making machinery because the application of menthol to the innerwrap, e.g., by spraying, while simultaneously unrolling, cutting, folding, and wrapping the innerwrap about the cigarette bundles is impractical and can still result in menthol contamination of the cigarette making machinery.
Because the foil of the sheet material innerwrap is usually aluminum, and aluminum is a metal notorious for its poor bearing qualities, including a high coefficient of friction and a tendency to gall, in most cases the innerwrap must be coated on the foil side with a polymeric “slip coating,” which prevents the foil side from adhering to the rollers of the cigarette making machinery and tearing the innerwrap web. In conventional innerwraps, the slip coating is a polyacrylate or a polyester, relatively expensive polymers. Although the slip coating is thin, because of the large production volumes, the total quantity and cost of the slip coating over time can be very high.
During the time the innerwrap is being stored and shipped to the cigarette manufacturing plant in rolls of the innerwrap material, there is an inevitable loss of menthol through sublimation and vaporization of the menthol flavorant. This loss is minimal because of the large volume-to-surface ratio of the roll. Menthol loss from the roll can be further reduced by wrapping the rolls in a vapor barrier.
Most of the menthol will be lost when the innerwrap is unwound from the large roll. When the roll is unwound, menthol on the paper will immediately begin to escape as vapor. This loss can be minimized by minimizing the time between unrolling the innerwrap material and wrapping the cigarette bundles. Ordinarily, this time will be short and the menthol loss slight. One loss that cannot be minimized is the loss of menthol from the slip-coated side of the innerwrap. Only the menthol on the paper side of the innerwrap will diffuse into the cigarettes. On the other hand, menthol on the slip coating side of the innerwrap cannot pass through the foil into the paper or cigarettes and will, therefore, diffuse through the paperboard box or soft pack wrapping and the outer polypropylene overwrap clear plastic.
When the innerwrap is rolled up, the menthol can readily diffuse from the paper into the slip coating, and the menthol will quickly reach an equilibrium in which a definite proportion of the menthol is retained in the slip coating. That proportion will ultimately not be in the cigarettes and will be wasted, except to the extent it imparts a menthol aroma to the consumer externally of the package. The menthol-affinity properties of the slip coating are thus important in affecting the amount of menthol that will be available to diffuse into the cigarettes and the amount that will be lost to the surrounding environment. Although the total surface area of the fibrous paper is much larger than the surface area of the smooth foil, a substantial amount of menthol still diffuses into or adheres to the conventional polymer slip coatings.
Polyvinyl alcohol (PVOH) has previously been used in the cigarette making art as an adhesive, for example, in making cigarette filters, but not, insofar as is known, as an innerwrap slip coating. U.S. Pat. No. 4,984,589 to Riedesser refers to GB-A-21 43 150 as disclosing a cigarette paper (tubular tobacco wrapper) coated on the side confronting the tobacco with polyvinyl acetate (PVA) or polyvinyl alcohol (PVOH) to prevent the penetration of condensate or tar that could form brown spots on the cigarette paper.
Thus, it would be desirable to minimize the amount of menthol that diffuses into or adheres to the slip coating during the time a cigarette innerwrap sheet material is stored. It would also be desirable to provide a low cost, yet effective, slip coating to replace the more expensive conventional slip coatings for cigarette package innerwraps.
SUMMARY OF THE INVENTION
The present invention relates to a cigarette package innerwrap having a polyvinyl alcohol (PVOH) slip coating. It has been found that PVOH is not only less expensive than conventional slip coating materials, it also has a relatively low coefficient of friction comparable to conventional slip coatings which makes it very effective in reducing the sticking of the aluminum foil of the innerwrap to the cigarette machinery rollers. In addition, as explained in more detail hereinafter, it has been unexpectedly found that PVOH is more effective than conventional slip coating materials in preserving the mentholation of packaged cigarettes by means of a menthol coating on the innerwrap paper.
On the basis of the chemical structure of PVOH, it would be expected that menthol would readily dissolve in PVOH and therefore that the amount of menthol lost to the slip coating of the innerwrap would be even greater with a PVOH slip coating than with conventional slip coating materials. However, contrary to the expectations of those skilled in the art, PVOH has a relatively low affinity for menthol. It has been unexpectedly found that the amount of menthol lost to the slip coating is less with a PVOH slip coating than with the prior art polyacrylate and polyester slip coatings.
Although the invention is not intended to be limited thereby, it is believed that the reason for this unexpected result is that the menthol does not dissolve in or adhere to the PVOH to the same degree that it does in the prior art slip coatings. The precise relationship between PVOH and menthol, as to their chemical affinity (adherence, solubility, etc.) or their other interactions that may explain the unexpected result of the present invention is not known.
With the foregoing and other objectives, features and advantages of the invention that will become hereinafter apparent, the invention may be more clearly understood by reference to the following detailed description of the invention and the appended claims.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention is directed to an innerwrap for cigarettes comprising a paper layer adhesively bonded (laminated) to a foil layer, such as an aluminum foil layer, and a polyvinyl alcohol slip coating on the foil layer. One form of the innerwrap structure consists of a 25 pound paper stock adhesively bonded with a silicate adhesive to a 0.00025 mil thick aluminum foil to which a PVOH slip coating is applied. The preferred method of applying the slip coating is to coat the foil layer with an aqueous solution of PVOH, allow the water evaporate, thereby leaving the PVOH on the foil layer as a slip coating.
The preferred PVOH coating composition comprises a 87.0% to 99.5% hydrolyzed, most preferably a 98.0% to 98.8% hydrolyzed polyvinyl alcohol resin with a molecular weight between 13,000 and 186,000 in an aqueous solution of about 1% to about 5% by weight of the polyvinyl alcohol resin. Because polyvinyl alcohol has a tendency to generate foam, a conventional defoaming agent is preferably added at a level of 0.1% to 0.3% by weight of the total weight of polyvinyl alcohol in the solution. A surfactant may is also preferably added to enhance surface wetting of the foil. A preservative may also added to increase the shelf life of the PVOH.
After the aluminum foil layer of the innerwrap is coated with the PVOH solution, the innerwrap is dried thoroughly and, in one aspect of the invention, the paper layer is coated with menthol or other flavorant. It will be understood that the term “coating,” as used in the specification and claims herein, means covering a surface with a layer of a material by any means, for example, by printing, spraying, dipping, brushing, vapor deposition, or any other method. When the innerwrap paper layer has been coated with menthol, e.g., either by the conventional neat mentholation process or ethyl alcohol solution process, or by some other method, the innerwrap is immediately wound onto a large roll. Once the menthol coating is enclosed in the large innerwrap roll, the menthol cannot readily escape because the menthol molecules cannot diffuse through the foil layer on either side of the paper, but can escape only by diffusing through the paper to the marginal edges of the paper at the roll ends which are the only free surfaces available for escape. If desired, the roll may be packaged in a barrier layer material to further inhibit escape of the menthol flavorant from the roll ends during storage since diffusion of the menthol to the roll ends will reach an equilibrium condition with the menthol vapor in the package. In addition, some of the menthol in the paper will diffuse into or adhere to the slip coating on the foil layer underlying and adjacent to the paper also until an equilibrium condition is reached.
At some later time, the innerwrap material is removed from storage and used on cigarette packaging machinery to wrap cigarette bundles. At the time of use, a proportion of the menthol will reside in the paper, and the remaining proportion, except for what escaped from the roll ends, will have diffused into or adhered to and resides in the adjacent slip coating. In the finished cigarette package, the menthol remaining in the slip coating will, of course, eventually dissipate to the surrounding environment, while that remaining in the paper will, over time, diffuse into and spread evenly throughout the cigarette tobacco. Thus, it is desirable to minimize the amount of menthol remaining with the slip coating when the innerwrap is unrolled.
As explained above, it has been found that a relatively small proportion of menthol is retained by the slip coating on the innerwrap foil layer when the slip coating is PVOH, as compared to innerwraps with conventional slip coatings. Thus, a greater percentage of menthol remains in the paper layer of the innerwrap making possible a greater mentholation level for a given amount of menthol or the use of a lesser amount of menthol for a given mentholation level.
EXAMPLE
Two rolls of a PVOH-coated foil innerwrap were tested in a mentholation process. One roll was tested in a neat mentholation process and the other in an ethyl alcohol solution process. For the alcohol solution process on Roll # 1 , the innerwrap was run at 200 meters per minute with the solution flow control set at 600 ml/1000 meters which is the recommended setting to obtain a pack menthol target of 0.3% of net tobacco weight. For the neat process, Roll # 2 was run at 200 meters per minute with the melt pump setting at 35% or 75 gm/min. For the same pack menthol target of 0.3% of net tobacco weight.
After completion of the mentholation process, both rolls were placed in a plastic bag and vacuum-sealed. The test foil innerwraps were then run on a cigarette packer approximately 2-3 hours later. There was little or no menthol crystal buildup on the foil coating. The rolls ran well on the packers with no machine problems.
The cigarette samples produced were tested for menthol content of the tobacco. Cigarettes packaged in innerwraps from both Rolls # 1 and # 2 were measured at 0.34% menthol by weight.
Additional tests of the PVOH coated innerwrap at different levels of pack menthol show the level of pack menthol is higher than the target menthol in the pack in both the neat mentholation process and the ethyl alcohol solution process. The results of those additional tests are tabulated in the following Table.
TABLE
Test ID No.
GN20889AB
GN20889AG
GN20889AE
GN20889AD
GN20889AF
GN20889AC
GN20889AA
Flow
580
580
33.5
44.7
770
999
63.3
Setting*
Neat or
Alcohol
Alcohol
Neat
Neat
Alcohol
Alcohol
Neat
Alcohol
General
Current CP
PVOH
PVOH
PVOH
PVOH
PVOH
PVOH
Comments
10's
Coated
Coated
Coated
Coated
Coated
Coated
Target
0.45
0.45
0.45
0.6
0.6
0.78
0.85
Menthol %
Test
0.48
0.62
0.51
0.66
0.63
0.84
0.9
Menthol %
*Flow setting for the alcohol solution process in ml/1000 meters and for the neat process in gm/minute.
Although certain presently preferred embodiments of the 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. | Polyvinyl alcohol (PVOH) is used as a slip coating on a cigarette package innerwrap to prevent the innerwrap from sticking to the rollers of cigarette packaging machinery during processing of the innerwrap material. PVOH unexpectedly has a low retention of menthol, as compared to conventional slip coating materials, which also makes it useful in mentholation processes that involve applying menthol to the innerwrap rather than to the cigarettes per se. | 8 |
BACKGROUND AND SUMMARY OF THE INVENTION
This is a division, of application Ser. No. 552,261 filed Feb. 24, 1975, now abandoned.
It has been demonstrated that for many types of buildings it is desirable to have wall sections formed of a brick exterior with a lining of tiles affixed to the bricks. Such wall sections have been shown in German Offenlegungsschrift No. 2,102,664. It has also been shown that in many instances it is desirable to make preformed wall sections. When constructing wall sections of bricks with a tile lining by hand, however, the procedure is very time consuming and complicated whether for preformed wall sections or those constructed in the field, and sometimes not economically practical.
According to the present invention, preformed wall sections having exteriors of brick, block, or the like with a lining of tile or the like are economically constructed automatically with a minimum of labor and wasted effort, yet the wall sections constructed thereby are of high quality and will remain intact even over extended periods of use. According to the present invention a preformed brick wall panel is disposed in a generally horizontal plane, a lining panel composed of individual tile members is assembled, proper spacings are introduced between the tiles, columns of mortar are disposed along the upper face of the horizontally disposed wall panel, and the lining panel members are transferred in groups or en masse to a position over the wall panel, and are then firmly pressed into engagement with the mortar columns. The mortar columns are preferably arranged so that when a wall section containing the same is in use, the columns will run vertically.
Exemplary apparatus according to the present invention may include vacuum grippers for transferring of the lining panel to position over the wall panel, flatbed cars movable on tracks for locating the wall panels in proper position, automatic means for applying all mortar columns simultaneously onto a wall panel upper face, and spacing means for introducing a predetermined space between various tiles of lining panel including a plurality of sets of plural levers interconnected to form a scissors-like device. Also, the vacuum grippers can be so constructed that they introduce the predetermined spacing between the tiles after lifting thereof from a horizontal surface.
It is an object of the present invention to provide improved apparatus for constructing preformed wall sections. This and other objects of the invention will become clear from an inspection of the detailed description of the invention and from the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a top plan view of an exemplary wall section being produced according to the present invention showing a step-by-step completion thereof utilizing exemplary apparatus according to the present invention;
FIG. 2 is a top plan view of an exemplary lining panel being formed according to the present invention for disposition on a wall panel, utilizing exemplary apparatus according to the present invention;
FIG. 3a is a side view of a portion of an exemplary lining panel and supporting apparatus therefor;
FIG. 3b is a detail top plan view with the lining panel removed of the exemplary apparatus shown in FIG. 3a;
FIG. 4a is a cross-sectional view of exemplary vacuum gripping apparatus in operative relationship with portions of a lining panel for movement thereof according to the present invention;
FIG. 4b is a cross-sectional view of the apparatus shown in FIG. 4a in operative relationship with portions of a lining panel for pressing thereof into engagement with a wall panel;
FIG. 5 is a top plan view of exemplary gripper and spacer means that may be utilized according to the present invention;
FIG. 6 is a side view taken generally along lines 6--6 of FIG. 5, showing the apparatus partly in elevation and partly in section; and
FIG. 7 is a perspective detail view of a portion of the vacuum gripper and spacing means of FIG. 5.
DETAILED DESCRIPTION OF THE INVENTION
Exemplary apparatus according to the present invention for effecting the method of the present invention is shown diagrammatically in the drawings. A horizontally disposed preformed wall panel, shown generally at A in FIG. 1, composed of bricks, blocks, or the like, 10 is preferably disposed on a generally flatbed car 12 or the like, which is movable along a track 14. The preformed wall panel A is adapted to be disposed so that line B--B therethrough is disposed in a vertical plane when a wall constructed with wall panel A is in use, as for forming the wall of a building. The wall panel A is adapted to have a preformed lining panel C, composed of tile members 25 or the like, affixed thereto to thereby form a finished wall section D. When the wall section D is in use -- for example as a wall of a building -- the tile lining panel C will be disposed toward the interior of the building, and the brick wall panel A will be disposed exteriorly thereof.
According to the present invention, the wall panel A and the lining panel C are readily and efficiently assembled. A preformed wall panel A on a car 12 is moved along track 14 until under a mortar applying device, such as shown at 15 in FIG. 1, for applying parallel spaced columns of mortar 16 on the upwardly facing surface thereof. It is preferred that the device 15 apply the mortar along lines parallel to line B--B and over and in grooves 11 between adjacent bricks 10 so that when a finished wall section is in use, the columns 16 will be disposed in a vertical plane.
A lining panel C to be affixed to a wall panel A is preferably formed as shown and with the apparatus in FIG. 2. A conveyor 20 or the like transports individual tile members 25 in the direction shown in FIG. 2 until a row of adjacent tiles is completed, then the tiles 25 are moved by conveyor 26 or the like onto a grouping table 28 or the like, and are aligned thereon with edges 30 of table 28. Each tile 25 may be of the type having a plurality of webs 24 formed on one surface thereof, however, tiles without webs are also readily utilizable. At least two webs 24 preferably are provided adjacent edges 23 of tiles 25 that have webs. Preferably, each of the tiles 25 is approximately of the same width -- or half the width -- as the bricks 10 onto which they are to be disposed.
After a group of tiles 25 are disposed on grouping table 28 to thereby form a lining panel C of unconnected tiles according to one embodiment of the present invention a space F is introduced in the direction E between each of the tiles 25 to thereby form a lining panel C of unconnected tiles. Preferably, the spacing of the tiles is accomplished by spreading means shown generally at 32 in FIGS. 3a and 3b. Such spreading means 32 includes a plurality of individual links 34 of equal length pivotally interconnected as points 35 and 36 thereof to form a scissors-like assembly. At each of the points 36 there is provided a pin 38 having an abutment ledge 40 formed thereon for extending upwardly through a slot 29 in grouping table 28 for engaging a web 24 of a tile 25. The pin 38 preferably is guided in slot 29 so that movement of the interconnected levers 34 of assembly 32 results in translational movement of the tiles 25 abutted by the ledges 40 of pins 38. By operation of the assembly 32 it is thus seen that a uniform space F is introduced between each of the tiles 25.
Dividing walls 41 or the like may be provided along the length of grouping table 28 to provide for spacing of the tiles 25 in the direction perpendicular to direction E, or the tiles 25 may be disposed adjacent to each other in that dimension.
After the spaces F have been introduced between the tile members 25 of lining panel C according to one embodiment of the invention, the panel is transferred as a whole (or conveniently segmented portions thereof) to a position directly over a wall panel A having mortar columns 16 disposed on a face thereof. The lining panel C is orientated so that a place passing through spaces F between tiles 25 thereof is parallel to and directly over each of the columns 16. Apparatus for moving the lining panel C into such operative engagement preferably consists of conventional vacuum gripping means, shown generally at 45 in FIGS. 4a and 4b. The means 45 includes a plate portion 47 thereof adapted to make surface-to-surface contact with the tops of the tiles 25 of the panel C, and having a vacuum connection 48 leading to the surface thereof. A vacuum applied through connection 48 causes the tiles 25 to tightly adhere to the plate portion 47, the spaced relationships therebetween being maintained. The tiles 25 may then be lifted by applying an upward force to hooks 50 of assembly 45, as shown in FIG. 4a. The hooks 50 or the like are preferably rigidly attached to a lifting plate 52 which is disposed generally parallel to gripping plate portion 47 and is movable with respect thereto because of the lost-motion connection 54 therebetween, which connection preferably is formed by pins 56 having spaced surfaces 58 and 59 thereof disposed on opposite sides of plate 52. By providing such a lost-motion connection, the chances of damage being done to the vacuum connection 48 are minimized while large forces may be applied with the assembly 45.
After lining panel C is lifted by vacuum gripping assembly 45 and placed into proper position over wall panel A having columns 16 of mortar or the like disposed thereon, the panel C is lowered onto the wall panel A and the tiles 25 thereof are pressed into engagement with bricks 10 or the like and mortar columns 16 thereof by means 45 by the application of a downward force therewith (as shown in FIG. 4b). Ledges 18 and 19 on cars 12 guide the movement of the assembly 45 in its downward path to insure proper positioning of the tiles 25 on the panel A. In the preferred form of the invention, with the mortar columns disposed over the grooves 11 between adjacent bricks 10 or the like, the mortar 16 will hold adjacent tiles 25 together, will be forced somewhat into grooves 11, and will hold the tiles 25 to the bricks 10 of wall panel A. Also, "breathing" spaces G will be provided between the bottom surfaces of the tiles 25 and the top surfaces of bricks 10 whereby proper ventilation is provided for the bricks, allowing for the transportation of the humidity diffusing through the bricks, thereby preventing freezing or loosening thereof due to the weather. The columns 16 also have smooth outside edges which allow water to run off the bricks without getting into the joints and loosening them.
According to another embodiment of the present invention, the same apparatus can be utilized for lifting the individual tiles of the preformed panel C and introducing the spacings between the tiles while lifted, and before pressing them into engagement with a wall panel A. Exemplary apparatus for accomplishing this is shown in FIGS. 5-7. Such apparatus may take the form of a plurality of vacuum grippers 64 interconnected by a grid of guide rails 62, 62a, and 63 and movable with respect thereto. The guide rails 62 and 62a may be affixed to a gripper frame 61, and the guide rails 63 and 63a may be movably mounted on guide rails 62 and 62a and on each other. The guide rails 63 and 63a are arranged perpendicularly with respect to each other, as are the guide rails 62 and 62a. Connected at each intersection point of guide rails 62, 62a, 63 and 63a is a vacuum gripper 64 or the like, having guiding pieces 65a and 65b thereof for cooperation with respective guide rails, as shown most clearly in FIG. 7. The guiding pieces provide for relative movement between the grippers 64 and the respective guide rails with which they are associated.
Means for moving the respective guide rails with respect to each other for introducing spacing between tiles 25' held by grippers 64 preferably comprise one or more push rods 66 in each dimension of the grid. Each push rod is preferably powered by a hydraulic cylinder 70 or other suitable power means for effecting movement thereof. At each intersection between a rod 66 and a guide rail over which it passes are a pair of collars 67 or the like for cooperation with a plate 72 or the like operatively connected to the respective rod 66. Each pair of collars 67 have a predetermined spacing therebetween. Movement of the respective guide rails by the respective push rods 66 results in movement of each of the grippers 64 attached to a particular guide rod. Such movement is transferred to the grippers by stops 68 operatively connected to preselected guide rails, which stops 68 cooperate with clamping plates 69 or the like on grippers 64. Although all grippers 64 may have plates 69 and stops 68 associated therewith, only the grippers around the periphery of the grid may have them, as shown in FIG. 5.
The operation of the gripper-associated separating means shown in FIGS. 5-7 is apparent from an inspection of the drawings. After tiles 25' or the like (such means may be used with tiles with or without webs) are picked up by vacuum grippers 64 cylinders 70 and 70' are actuated, which move the respective push rods 66 connected thereto a predetermined distance H. Because of the relative spacing between the collars 67 of rods 66, and the predetermined spacings of the stops 68, each of the grippers 64 within a row or column is moved a predetermined distance with respect to the grippers in the other rows and columns and the plate 61 to effect spacing of the tiles 25'. For instance, the grippers 64 in the row closest to cylinder 70 are moved a distance H1, while the grippers in the next row are moved a distance H2<H1, the grippers in the fourth row are moved only slightly or not at all. The same is true with respect to the grippers in the columns. Of course, the distances H, H1, H2, etc. can be set to any value by adjustment of the collars 67 and stops 68 (the collar spacing is inversly proportional to the stop spacing), and the distance H can be varied between the columns and rows so that greater or lesser spacing is introduced along each of the directions J and K.
The method of producing a finished wall section utilizing apparatus according to the present invention includes the following steps: A wall panel A formed of bricks, blocks, or the like is disposed in a generally horizontal plane. The panel A is adapted to be disposed vertically when serving as a finished wall section. A plurality of tiles 25 or the like, having webs 24 formed on a surface thereof, are arranged in a generally horizontal plane so that the webs 24 are on the bottom of the tiles 25', to thereby form an unconnected lining panel C. Uniform spaces F are introduced -- as in direction E -- between the individual tiles 25 or 25'. When the spreading means 32 is utilized, the spacing is introduced before the individual tiles of the preformed panels are lifting from the table 28 by vacuum grippers 45 or the like, while when the vacuum grippers 64 are utilized the predetermined spacings are introduced after the tiles are lifted from the table 28. The lining panel C is then in condition to be transferred directly over to a wall panel A, for application thereto.
A wall panel A has a plurality of evenly-spaced columns 16 of mortar or the like applied over the upwardly facing surface thereof, as with means 15. Preferably, the columns 16 are arranged so that when the finished wall section of which panel A will be a part is in use, the columns 16 will be vertical. Also, the columns 16 are preferably applied over the grooves 11 between the bricks 10 making up the wall panel A.
After columns 16 are arranged on panel A, and lining panel C is assembled and the tiles therein properly spaced, and are transferred in groups or en masse to a position just above the panel A, they are ready to be attached to panel A. The panel C may be arranged so that the spaces F between the tiles 25 are parallel to and just above mortar columns 16 (the webs 24, if any, being adjacent the spaces F). Then with the help of guide ledges 18 and 19 on car 12 or the like on which the panel A is disposed, the lining panel C is brought into engagement with the panel A, and is pressed down thereon by means 45 or 64, resulting in the tiles 25 or 25' being secured to the bricks 10 of panel A by the mortar 16.
Simple and efficient apparatus according to the present invention is provided for producing high-quality pre-formed finished wall sections with tiles with or without webs. While the invention has been herein shown and described in what is presently conceived to be the most practical and preferred embodiment, it will be apparent to one of ordinary skill in the art that many modifications may be made thereof within the scope of the invention. For instance, other mortar applying means, gripping means, and spacing means could be utilized, or the mortar columns could be orientated in a different manner. Also, other materials could be used. Other modifications are also possible. Thus it is intended that the present invention be limited only by the scope of the appended claims. | Apparatus for automatically constructing prefabricated wall sections of brick wall panels with a tile lining. A prefabricated brick wall panel has columns of mortar disposed in parallel strips thereon, a lining panel of unconnected tile members is assembled, proper spacing being introduced between each of the tile members, and the tile members are transferred in groups or en masse to a position over the wall panel. The lining panel members are then firmly pressed into engagement with the wall panel with mortar columns therealong, thereby forming a completed wall section. Preferred specific apparatus includes vacuum grippers, scissor-connected link spacing means, and flatbed cars movable on tracks to a position below automatic mortar applying means. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to techniques for detecting magnetic ink characters on documents and recognizing them. In particular, the invention relates to the technology of suppressing fluctuations in magnetic ink character detection signals caused by suboptimal printing of magnetic ink characters.
2. Description of the Related Art
FIG. 9 shows a schematic view of a conventional magnetic ink character detection apparatus. In FIG. 9, magnetic head 1 is used as a magnetic signal detection unit, and a DC motor 11 is used as a drive source for transporting the medium on which magnetic ink characters are printed. The medium is transported by a transport mechanism composed of a transmission belt 10 and a rubber roller 6. When a magnetic ink character printed on the medium passes over magnetic head 1, magnetic head 1 converts the magnetic flux generated by the magnetic ink character into an electrical signal.
Generally, the scanning height for a magnetic head is provided in the direction in which the medium is transported. The scanning height is designed to be wider than the height of the magnetic ink characters. Prior to the detection processing, the magnetic ink characters are remagnetized to a specified polarity. This causes the magnetic head to output an electrical signal converted from a magnetic flux representing a change in the height component (also referred to as the vertical component) of a given magnetic ink character.
The shapes of magnetic ink characters are standardized under ISO/R1004, so that fixed electrical signal waveforms are produced by a predetermined transport speed of the medium. FIG. 5 shows an example of magnetic ink characters that are printed on medium 8. Magnetic ink characters may be printed in either of two fonts: E13B and CMC7. The font shown in the FIG. 5 is E13B. The signal waveform shown in the lower portion of the figure represents a change as a function of time of the electrical signals that are output from amplification circuit 2, wherein the magnetic ink character detection apparatus reads the medium in FIG. 5 from "0" to "3".
As the signal waveform indicates, the signal shows a positive peak based on a change in the vertical component of a magnetic ink character, at the local maximum of the change ratio in the vertical component. Similarly, the signal shows a negative peak at the local minimum of the change ratio in the vertical component. The magnitude of a peak depends upon the rate of increase or decrease of the vertical component.
When detecting a magnetic ink character by transporting a medium, the apparatus first amplifies the electrical signals that have been output by the magnetic signal detection unit, detects the positive and negative peaks, and then it determines the peak positions on the time axis. The apparatus can detect a magnetic ink character by determining that the positive peak position of the first waveform as the beginning of a given character, and by detecting the presence or absence of the positive and negative peaks of waveforms at a fixed interval that is determined by the transport speed of the medium.
When a magnetic ink character has been detected, the character is recognized by the positions at which the positive peaks and the negative peaks of the signal waveforms that are associated with the characters have been pre-stored as pattern data. The pattern data associated with magnetic ink characters are synchronized with specific starting positions on the basis of detected signal waveforms, and the magnetic ink characters are recognized by referencing the pattern data.
In the related art described above, however, in cases where the conditions under which magnetic ink characters are printed in different conditions between one medium and another, the positive and negative peak values of the electrical signals that are output from the magnetic signal detector can vary from one medium to another. Specifically, if the magnetic ink contains a high concentration of a magnetic material, or the character height is substantially increased because of an increase in the width of lines composing the characters due to print smudging (hereinafter referred to as a "positive scattering"), the signal peaks that are output by the magnetic head increase. Conversely, if the concentration of magnetic material is low or the character height is substantially decreased due to a decrease in line width (hereinafter referred to as a "negative scattering"), the signal peaks that are output by the magnetic head decrease.
If the magnetic ink characters that are printed exhibit a positive scattering, the electrical signals that are output are amplified to a greater amplitude by the succeeding amplification circuit. If the amplified electrical signal, after amplification, is greater than the maximum output voltage of the amplification circuit, i.e., if the electrical signal exceeds the dynamic range of the amplification circuit, the electrical signal waveform exhibits a saturation state as shown in FIG. 6. In the figure, the area indicated by Tpk1a, Tpk1b, Tpk1c and Tpk1d represent a saturated area. Thus, a problem in the related art is that in a saturated condition, the position at which the peak of a waveform occurs can be indeterminate.
By contrast, if a printed magnetic ink character scatters negatively, the signal that is output from the magnetic head decreases. Consequently, the signal amplitude that is output by the amplification circuit also decreases, as shown in FIG. 7. As indicated by the broken lines in FIG. 7, normally a signal waveform contains an overlapping external noise, such as magnetic noise. Therefore, if the position of a peak in the signal waveform is detected by using a conventional peak detection method, the peak detection position fluctuates in the range indicated by Tpk2 in FIG. 7.
Therefore, in the aforementioned conventional recognition method that uses peak positions of the detection signals for the recognition of characters, the inability to accurately determine peak positions results in an decrease in the recognition probability of magnetic ink characters.
OBJECTS OF THE INVENTION
Therefore, it is an object of the present invention to improve the accuracy of magnetic ink character recognition during the presence of positive and negative scattering conditions. More specifically, an object of the present invention is to detect magnetic ink characters in a stable manner without requiring an adjustment to the amplitude of the amplification circuit.
Another object of the present invention is to enhance the probability of recognition of magnetic ink characters even under printing conditions that vary from one medium to another causing the amplitude of magnetic ink character detection signals to vary from one medium to another.
SUMMARY OF THE INVENTION
To achieve these and related objects, the magnetic ink character detection apparatus of the present invention includes a moving device that moves the magnetic head and the medium relative to each other at a prescribed speed; an amplitude detection unit that detects the amplitude and/or saturation of the electrical signals output from the magnetic head; and a moving-speed determination unit that determines the relative moving speed caused by the moving device in response to the output from the amplitude detection circuit.
If the amplitude detected by the amplitude detection unit is small, the amplitude of the electrical signal detected from the magnetic head can be increased by increasing the relative moving speed produced by the moving device. Similarly, if the saturation of electrical signals is detected by the amplitude detection unit, the saturation of electrical signals can be prevented in the successive trial by setting the lower relative moving speed that is produced by the moving device.
In this case, it is preferable that the moving speed determination unit comprises a speed change magnitude determination device that determines the magnitude of change in speed that corresponds with the amplitude and/or saturation amount of the electrical signals that are detected by the amplitude detection unit; and a speed update device that determines the moving speed based upon the current moving speed settings and upon the magnitude of change in speed that has been determined by the speed change magnitude determination device.
In this case, it is even more desirable that the amplitude detection unit comprises in part an analog to digital conversion circuit that converts into digital values the electrical signals that are output from the magnetic head, and that this portion of the amplitude detection unit outputs the amplitude and/or saturation amount of electrical signals as digital values. Moreover, it is desirable that the speed change magnitude determination includes a conversion table memory that stores a conversion table for converting the amplitude and/or saturation amount of electrical signals into the speed change magnitude.
The present invention described above may also be recognized as a computer-implemented method of controlling a magnetic ink character detection apparatus. The control method described below can provide remarkable effects as an application of the above mentioned present invention. Specifically, the control method comprises a first moving process that moves the magnetic head and a medium at a prescribed speed relative to each other; an amplitude detection process that detects the amplitude and/or saturation amount of the electrical signals that are output from the magnetic head; a moving-speed determination process that determines the relative-moving speed in the moving process according to the detection results from the amplitude detection process; a second moving process that resets the relative positions of the magnetic head and the medium to the initial condition, namely the condition before the execution of the first process; and a third moving process that moves, relative to each other, the magnetic head and the medium at the relative-moving speed that was determined by the moving-speed determination process.
Other objects and attainments together with a fuller understanding of the invention will become apparent and appreciated by referring to the following description and claims taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings wherein like reference symbols refer to like parts
FIG. 1 shows a block diagram that depicts the underlying technological philosophy of the magnetic ink character detection apparatus of the present invention;
FIG. 2 shows a schematic view of first embodiment of the magnetic ink character detection apparatus according to the present invention;
FIG. 3 shows a flowchart depicting the operation of the first embodiment of the magnetic ink character detection apparatus according to the present invention;
FIG. 4 shows a schematic view of a second embodiment of the magnetic ink character detection apparatus according to the present invention;
FIG. 5 shows an example medium on which magnetic ink characters are printed, and the signal waveforms that are generated when the medium is read by a magnetic head;
FIG. 6 shows signal waveforms that are generated when the medium undergoes an increase in scattering;
FIG. 7 shows signal waveforms that are generated when the medium undergoes a decrease in scattering;
FIG. 8 shows signal waveforms with optimal signal amplitudes after a speed correction according to the present invention; and
FIG. 9 shows a schematic view of a conventional magnetic ink character detection apparatus.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 is a block diagram that shows the underlying technological philosophy of the present invention. Medium 21, on which magnetic ink characters 22 are printed, and magnetic signal detection unit 24 are moved relative to each other by moving unit 23. The speed at which the objects are moved by moving means 23 is set by moving-speed determination unit 30 to be described hereinbelow. While moving relative to medium 21, magnetic signal detection unit 24 converts the magnetic signals detected from magnetic ink characters 22 into electrical signals 25, and transmits them to the amplitude detection unit 28. Amplitude detection unit 28 detects the amplitude of electrical signals 25, i.e., peak values, and transmits amplitude information 29 to moving speed determination unit 30. It should be noted that, preferably amplitude-detection unit 28 also detects whether electrical signals 25 are in a saturated state, and preferably it transmits information 29 to the moving speed determination unit. Based upon both information 29 regarding amplitudes and the current moving speed, moving-speed determination unit 30 determines a new moving speed.
Of course, the new moving speed is set so that at that moving speed, electrical signal 25 will have an appropriate amplitude. Thus, when electrical signal 25 is in a saturated state, a slower moving speed is specified to allow for the extent of the saturation. When the amplitude of electrical signal 25 is smaller than a specified value, a faster moving speed is specified based upon the extent to which the amplitude is smaller.
Moving speed 31, determined by moving-speed determination unit 30, is transmitted to moving unit 23. Then, as described above, moving unit 23 relatively moves medium 21, on which magnetic ink characters 22 are printed, against magnetic signal detection unit 24 according to the moving speed 31 that has previously been determined.
FIG. 2 shows a schematic view of the first preferred embodiment. Medium 8, on which magnetic ink characters are printed, is transported by rubber roller 6. Rubber roller 6 is driven by stepping motor 9 through transmission belt 10. The material of which rubber roller 6 is made is by no means limited to rubber; any known material having an appropriate friction coefficient relative to the material of the magnetic ink character recording carrier, e.g., personal check, may be used. This example uses stepping motor 9 as a drive source for the transport mechanism. By rotating the motor either in the positive direction or in reverse, the medium can be moved either forward or backward.
Stepping motor 9 is a so-called hybrid motor, which is controlled by an information processor (hereinafter referred to as "CPU 4") through drive circuit 7. Four signal wires are connected from CPU 4 each corresponding to the driving coils in the stepping motor to drive circuit 7 so that the motor can be operated in 2 phases or in 1-2 phases. The signal waveforms that travel through the signal wires when driving stepping motor 9 are well known to the art; therefore, a more detailed description thereof is omitted herein.
Magnetic head 1, which is an example of magnetic signal detection unit, converts the magnetic ink characters that are printed on medium 8 into electrical signals. Because magnetic head 1 is well known to the art, a detailed description thereof is also omitted herein. The signals, after being converted, are amplified into larger amplitudes. It should be noted here that amplification unit 2 may be omitted if the amplitudes of the output signals from magnetic head 1 are large enough. However, because the output from magnetic head 1 generally constitutes a current, the currents should be converted to voltages in order to accommodate the signal processing required in subsequent steps. At fixed sampling intervals, the amplified electrical signals are discretized by A/D conversion circuit 3 and are stored in memory circuit 5 by CPU 4. Therefore, the sampled values of signal waveforms are stored in memory circuit 5 in the order in which they were sampled.
The preferred control method executed by the CPU 4 generally comprises a first moving process 123a that moves the magnetic head 1 and the medium 8 at a prescribed speed relative to each other; an amplitude detection process 128 that detects the amplitude and/or saturation amount of the electrical signals that are output from the magnetic head 1; a moving-speed determination process 130 that determines the relative-moving speed in the moving process according to the detection results 29 from the amplitude detection process 128; a second moving process 123b responsive to the moving speed determination process 130 that resets the relative positions of the magnetic head 1, and the medium 8 to the initial condition, namely the condition before the execution of the first moving process 123a; and a third moving process 123c that moves, relative to each other, the magnetic head 1 and the medium 8 at the relative-moving speed that was determined by the moving-speed determination process 130.
It should be noted here that components of this invention, namely the amplitude detection process 128, the moving speed determination process 130, and the first (123a). second (123b) and third (123c) moving processes shown in FIG. 2 may be conveniently implemented using an information processor such as CPU 4 (FIGS. 2, 4) programmed according to the teachings of the present disclosure, as will be apparent to those ordinarily skilled in the computer arts. Appropriate software coding can be readily prepared based on the teachings of the present disclosure, as will be apparent to those ordinarily skilled in the software arts. The present invention may also be implemented by the preparation of application specific integrated circuits ("ASICS") or by interconnecting an appropriate network of conventional component devices and circuits, as will be readily apparent to those ordinarily skilled in the electronics arts.
In each of the preferred embodiments of the present invention described herein, the amplitude detection process 128, the moving speed determination process 130 and the first (123a), second (123b) and third (123c) moving processes take the form of either independent or interdependent threads or processes executed by CPU 4 as shown in FIGS. 2 and 4 (discussed in more detail hereinbelow). These threads permit media speed adjustment and compensation processes to be carried out according to the present invention when CPU reads and executes their corresponding programming instructions from a computer readable storage medium. Although here CPU 4 reads programming instructions corresponding to amplitude detection process 28, moving speed determination process 130, and the first (123a), second (123b) and third (123c) moving processes from memory circuit 5 principally composed of RAM, it should be recognized that the teachings of the present invention are not so limited, and that storage medium may include any type of disk media, removable or fixed, local to CPU 4 or remotely accessible through an intermediary device or network. Such disk media may include floppy disks (e.g. floppy disk 55 readable by CPU 4 through conventional disk interface 50), optical disks such as CD-ROMs and DVD articles, hard drives or disk arrays, whether physically located within or external to CPU 4. Of course, as preferred, the storage medium can comprise a solid state memory such as ROM, RAM, EPROM, EEPROM, Flash EEPROM or any combination thereof, as long as it is capable of storing the necessary programmed instructions and can be accessed by CPU 4.
The following is a description of the operation of the present embodiment using a flowchart (FIG. 3) that indicates the control sequence of the aforementioned processes employed in the present embodiment as executed by CPU 4. First, operation that occurs when the magnetic ink characters printed on medium 8 have a positive scattering will be described. In step S1, CPU 4 sets the pulse rate for stepping motor 9, i.e., the step rate, to a default value (first moving process 123a), and then it initiates transporting the medium. In step S2, medium 8 is transported. The waveforms of the electrical signals that are generated from the magnetic ink characters printed on medium 8 are stored in memory circuit 5 by the aforementioned processing with reference to FIG. 1 discussed above.
The waveforms are stored, based upon the numerical values that are stored in memory circuit 5 (assuming the detected signals in determination S3 exceed known thresholds, indicating they are mostly character information rather than noise.) In step S4, CPU 4 checks to see whether there are any saturated profiles within the signal waveforms, as shown, for example, in FIG. 6. This processing will be described in more detail hereinbelow. The testing in step S4 is performed by differentiating the set of numerical values. Because sampled values are employed in this embodiment, the testing process calculates the differences between successive sample values. If saturation points exist, the derivative becomes 0 in the neighborhood of a local maximum or a minimum point. The testing process examines if two or more such points are detected. And, if three or more points having zero derivatives within a single local maximum or minimum are detected in the sets of numerical values representing the waveform, the occurrence of saturation may be concluded with a relatively high degree of certainty (steps S3 and S4 together constitute the amplitude detection process 128).
When saturation points are detected in this manner, in step S5 (i.e. moving speed determination process 130), CPU 4 sets the pulse rate, i.e., the step rate, for stepping motor 9 to a value lower than the value used the present trial. To accomplish this, first the CPU extracts the saturation point having the greatest width among all the saturation points that are found. This is done, for example, by selecting the saturation area having the greatest number of sampling points having zero derivatives with the neighboring sampling points. Then, the CPU determines either the absolute value or the ratio of the step rate that is to be reduced according to the number of the maximum sampled points included in a single saturation area. And, finally, the CPU changes the previous step rate in terms of the absolute value or the ratio. Because the magnitude of a peak value generally increases in proportion to the transport speed of the media, step rates should preferably be changed by using the ratio value rather than the absolute value.
For determining the magnitude of change in speed described above, the relationship between the sample points and the magnitude or ratio or change should be stored in memory, such as in ROM, in the form of a table. This scheme permits the rapid setting of new transport speeds.
Upon completion of the step rate setting process in step S5, in step S6 the CPU 4 runs the motor in reverse to operate the transport mechanism in reverse so that medium 8 is returned to the beginning-of-read position (i.e. second moving process 123b). Subsequently, in step S2, according to the step rate that has been set, CPU 4 transmits control signals to drive circuit 7, and by again transporting the medium, causes magnetic head 1 to detect magnetic ink characters (i.e. third moving process 123c). If favorable signal amplitudes are not obtained in this process, the CPU may successively repeat the above processing steps.
By contrast, in the case of a negative scattering, the waveforms obtained from medium 8 assume the forms shown, for example, in FIG. 7. As noted previously, when the amplitude, i.e., the peak, of the output waveform from the amplifier is small, as indicated in FIG. 7, the effects of overlapping noise produces an error in peak position by the width indicated by Tpk2. This prevents an accurate determination of the peak position. Therefore, the CPU sets a predetermined threshold level, and, in step S3, it compares each of the peak value of a waveform with the threshold level. If the maximum peak value is less than the threshold level, in step S7, CPU 4 sets the pulse rate for stepping motor 9 at a level higher than the pulse rate used during the previous test run, and it performs another detection with the increased transport speed of medium 8 (steps S6 and S2).
In step S7, the CPU extracts sampling points that are nearest the threshold level. The CPU then determines either the absolute value or the ratio by which the step rate must be increased according to the wave heights of the sample points. The CPU then changes the previous step rate by using this value. As noted previously, the relationship between sample point wave heights and step rate correction values should be prepared in memory as a table.
FIG. 4 depicts a second preferred embodiment of the present invention. DC motor 11 is used as a drive source for the transport mechanism shown in FIG. 2. A supply voltage source 12 is provided for supplying a specified drive voltage to DC motor 11. Supply voltage source 12 is organized in such a manner that the voltage to be applied to DC motor 11 can be varied. Changing the applied voltage changes the transport speed of the medium. In FIG. 4, three control wires are connected from CPU 4 to the supply voltage source 12 so that the supplied voltage can be varied in three steps. Because voltage sources with a variable output voltage are well known to the art, a description thereof is omitted herein. The simplest configuration may be a combination of a D/A converter and a voltage follower as is known to those ordinarily skilled in the art.
The operation of this embodiment is similar to those of the aforementioned examples, and accordingly does not require a detailed description herein. The important point, however, is the substitution of supplied voltage change for step rate change and similar processing adjustments. As in the aforementioned operation of the first embodiment, if the printed magnetic ink characters exhibit a positive scattering, CPU 4 sets a low supplied voltage in the supply voltage source 12 and reruns the test. This reduces the voltage supplied to DC motor 11, and consequently reduces the transport speed for medium 8. This permits the reduction of the positive and negative peak values obtained from medium 8 to an extent that the peak values do not saturate. On the other hand, if medium 8 exhibits a negative scattering, CPU 4 increases the supplied voltage from supply voltage source 12. By increasing the transport speed of medium 8 in this manner, the CPU can increase the positive and negative peak values produced to a level greater than a specified value.
While the invention has been described in conjunction with several specific embodiments, it is evident to those skilled in the art that many further alternatives, modifications and variations will be apparent in light of the foregoing description. Thus, the invention described herein is intended to embrace all such alternatives, modifications, applications and variations as may fall within the spirit and scope of the appended claims. | An apparatus and control method therefor which compensates differences among individual media in detected signal amplitudes caused by imperfect magnetic ink character printing conditions without requiring an adjustment of amplitude of a received signal amplifier. Preferably, the magnetic ink character detection apparatus of the present invention includes a moving device that moves the magnetic head and/or the medium relative to each other at a predetermined speed; an amplitude detection unit for detecting the amplitude and/or saturation amount of the electrical signals output from the magnetic head; and a moving-speed determination unit for determining the relative moving speed caused by the moving device in accordance with the output from the amplitude detection unit. | 6 |
[0001] This nonprovisional application claims priority under 35 U.S.C. § 119(a) on Patent Application No. 2006-342118 filed in Japan on 20 Dec. 2006 and under 35 U.S.C. § 119(e) on U.S. Provisional Application No. 60/884,562 filed on 11 Jan. 2007, which are incorporated by reference.
BACKGROUND OF INVENTION
[0002] 1. Field of Invention
[0003] The present invention relates to an assembly method for a device that employs electric ignition, such as an air bag device, and a method of distinguishing between two electroconductive pins provided in an electric igniter.
[0004] 2. Description of Related Art
[0005] In an electric igniter having two electroconductive pins (a center pin and an eyelet pin) for electrifying a heating wire (a body that generates heat through electric resistance) or an igniter assembly using the electric igniter, positive and negative electrodes are usually connected to predetermined electroconductive pins, and when a positive or negative electrode is connected to the wrong electroconductive pin, a defective product is obtained.
[0006] FIG. 1 illustrates the structure of a known igniter assembly 10 . An electric igniter 20 is coupled integrally to a metallic igniter collar 30 by a resin 31 .
[0007] In the electric igniter 20 , a center pin 21 a is insulated from a metallic header (eyelet) 23 by a glass member 22 and connected to a heat-generating body (bridge wire) 24 . An eyelet pin 21 b is connected to the eyelet 23 and connected to the heat-generating body (bridge wire) 24 via the eyelet 23 . An ignition agent 26 is charged into a tubular spacer 25 so as to press against the heat-generating body (bridge wire) 24 . The eyelet 23 and the tubular spacer 25 are covered from the outside by a metallic cover 27 , together forming an ignition portion of the electric igniter 20 . Further, the metallic cover 27 of the ignition portion is covered by a resin cover 28 having an electric insulation property. A space 29 serves as a space for inserting a connector plug having a lead wire.
[0008] As shown in FIG. 1 , the igniter assembly 10 has a structure in which a resin 31 is molded between the igniter 20 and igniter collar 30 , and therefore it is impossible to distinguish between the center pin 21 a and the eyelet pin 21 b from the outer form thereof.
[0009] Conventionally, the center pin 21 a is distinguished from the eyelet pin 21 b by means of X-ray projection, but X-ray projectors and X-ray lamps are both expensive, leading to an increase in maintenance costs that is reflected in the manufacturing costs of the igniter JP-A No. 2001-165600 and JP-A No. 2006-35970 may be related arts of the present invention.
SUMMARY OF INVENTION
[0010] One of the inventions provides a method of assembling a device employing electric ignition by comprising assembling an igniter assembly in the device, the igniter assembly having an electric igniter provided with a first electroconductive pin and a second electroconductive pin, connected to a power source, the method comprising steps of:
[0011] forming two measurement circuits by using the first electroconductive pin and the second electroconductive pin as a measurement terminal on one end side, respectively, and using another member provided in the igniter assembly as a terminal on the other end side with a pass through a dielectric provided in the igniter assembly,
[0012] measuring pure resistances and/or impedances of the two measurement circuits, respectively, by applying a high frequency thereto separately,
[0013] distinguishing the first electroconductive pin from the second electroconductive pin from a magnitude relationship (difference) between the measured pure resistance and/or impedance values, and
[0014] then, disposing the igniter assembly to the device such that the first electroconductive pin and the second electroconductive pin correspond to predetermined power source electrodes, respectively.
[0015] In other words, it is an assembly method for a device employing electric ignition, including a step of attaching an igniter assembly to the device,
[0016] wherein the igniter assembly has an electric igniter having a first electroconductive pin and a second electroconductive pin for connecting the electric igniter to a power source,
[0017] two measurement circuits passing through a dielectric provided in the igniter assembly are formed such that the first electroconductive pin or the second electroconductive pin serves as a measurement terminal on one end side and another member provided in the igniter assembly serves as a terminal on another end side, and
[0018] a high frequency is introduced separately into the two measurement circuits to measure pure resistances and/or impedances, and the first electroconductive pin is distinguished from the second electroconductive pin from a magnitude relationship (difference) between the measured pure resistance and/or impedance values, whereupon the igniter assembly is attached to the device such that the first electroconductive pin and the second electroconductive pin correspond to predetermined power source electrodes.
[0019] Another one of the inventions provides a method of distinguishing between a first electroconductive pin and a second electroconductive pin, provided in an electric igniter in an igniter assembly including the electric igniter, comprising steps of:
[0020] forming two measurement circuits passing through a dielectric, provided in the igniter assembly, such that the first electroconductive pin and the second electroconductive pin serves as a measurement terminal on one end side and another member provided in the igniter assembly serves as a terminal on another end side; and
[0021] measuring pure resistances and/or impedances of the two measurement circuits, respectively, by applying a high frequency thereto separately, and distinguishing between the first electroconductive pin and the second electroconductive pin from a magnitude relationship (difference) between the measured pure resistance and/or impedance values.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] 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 limitative of the present invention and wherein:
[0023] FIG. 1 shows a vertical cross-sectional view of a known igniter assembly to which the present invention is applied;
[0024] In FIG. 2 , (a) shows a sectional view of an igniter assembly for illustrating an assembly method and a distinguishing method of the present inventions and a schematic view of high-frequency resistance measurement circuits including the igniter assembly, and (b) shows an equivalent circuit diagram of the igniter assembly shown in (a) in high-frequency resistance measurement; and
[0025] In FIG. 3 , (a) shows a sectional view of a gas generator having an igniter assembly for illustrating an assembly method and a distinguishing method of the present invention, and a schematic view of high-frequency resistance measurement circuits including the igniter assembly, and (b) shows an equivalent circuit diagram of the gas generator shown in (a) in high-frequency resistance measurement.
DETAILED DESCRIPTION OF INVENTION
[0026] The present invention provides an assembly method for a device that employs electric ignition, such as an air bag device, with which it is possible to distinguish between two electroconductive pins provided in an igniter assembly and an electric igniter, thereby improving the reliability of the device.
[0027] The present invention also provides a method of distinguishing between two electroconductive pins provided in an igniter assembly and an electric igniter.
[0028] By employing a commercially available high-frequency resistance measuring device, the sign, positive or negative, of the two electroconductive pins can be confirmed easily. Hence, in comparison with a conventional method employing an X-ray projector, manufacturing costs can be reduced.
[0029] Various devices, such as an occupant-protecting air bag device (a gas generator for an air bag) or a seatbelt pretensioner installed in a vehicle such as an automobile, may be cited as examples of a device employing electric ignition.
[0030] An igniter assembly in which a collar member is incorporated into a lower portion (including a part of the electroconductive pins) of an electric igniter via a resin, and a gas generator in which a cap member is fixed to the collar member of the igniter assembly and a gas generating agent is charged between the electric igniter and the cap, or in other words a gas generator having an igniter assembly, may be cited as examples of an igniter assembly.
[0031] The present invention preferably provides the assembly method, wherein the dielectric is an electric insulation cover covering an ignition portion of the electric igniter.
[0032] The present invention preferably provides the assembly method, wherein the dielectric is a resin which integrally couples a metallic igniter collar to the electric igniter.
[0033] By employing a commercially available high-frequency resistance measuring device, the sign, positive or negative, of the two electroconductive pins can be confirmed easily. Hence, in comparison with a conventional method employing an X-ray projector, manufacturing costs can be reduced.
[0034] The present invention preferably provides the method of distinguishing between a first electroconductive pin and a second electroconductive pin, wherein the dielectric is an electric insulation cover covering an ignition portion of the electric igniter.
[0035] The present invention preferably provides the method of distinguishing between a first electroconductive pin and a second electroconductive pin, wherein the dielectric is a resin which integrally couples a metallic igniter collar to the electric igniter.
[0036] By applying the distinguishing method of the present invention, it is possible to distinguish between two electroconductive pins provided in an igniter assembly easily and at a lower cost than a conventional method. Therefore, when assembling an automobile safety device such as an air bag device (a gas generator for an air bag) or a seatbelt pretensioner, the respective electroconductive pins can be attached appropriately to the corresponding ignition power source electrodes, without confusing the two electroconductive pins, as a result of which the reliability of the device is improved.
EMBODIMENT OF INVENTION
(1) Assembly Method or Distinguishing Method in FIG. 2
[0037] FIG. 2( a ) is a sectional view of an igniter assembly for illustrating an assembly method and a distinguishing method of the present invention, and a schematic view of high-frequency resistance measurement circuits including the igniter assembly. FIG. 2( b ) is an equivalent circuit diagram of high-frequency resistance measurement performed on the igniter assembly shown in FIG. 2( a ).
[0038] The igniter assembly 10 is identical to the igniter assembly shown in FIG. 1 , in which an ignition portion (the metallic cover 27 and the interior thereof) of the electric igniter 20 is covered by the resin cover 28 (electric insulation cover), which has an electric insulation property.
[0039] In high-frequency resistance measurement of the igniter assembly 10 , a first measurement circuit having the center pin (first electroconductive pin) 21 a as a terminal on one end side and the resin cover 28 as a terminal on the other end side and a second measurement circuit having the eyelet pin (second electroconductive pin) 21 b as a terminal on one end side and the resin cover 28 as a terminal on the other end side are formed. In these circuits, the resin cover 28 and the glass member 22 serve as dielectrics.
[0040] A high-frequency resistance measuring device 40 is disposed on the first measurement circuit and second measurement circuit. A device described in Examples may be used as the high-frequency resistance measuring device.
[0041] When a high frequency is introduced into the first measurement circuit (between the resin cover 28 and the center pin 21 a ) by the high-frequency resistance measuring device 40 , the resin cover (dielectric) 28 becomes a capacitor C 0 , the glass member 22 becomes a capacitor C 1 , the bridge wire 24 becomes a resistor R 1 ( 2 Q), and the metallic cover 27 , eyelet 23 and center pin 21 a become non-resistive conductors.
[0042] Meanwhile, when a high frequency is introduced into the second measurement circuit (between the resin cover 28 and the eyelet pin 21 b ) by the high-frequency resistance measuring device 40 , the resin cover (dielectric) 28 becomes a capacitor C 0 , and the metallic cover 27 , eyelet 23 and eyelet pin 21 b become non-resistive conductors.
[0043] Hence, the first measurement circuit and second measurement circuit differ in circuit configuration and the path along which the high frequency flows, and therefore also differ in high-frequency resistance (pure resistance and/or impedance). Therefore, when an appropriate high frequency is selected and measurement is performed at this high frequency, a magnitude relationship occurs between the measured high-frequency resistance values. Accordingly, by measuring the high-frequency resistance (pure resistance and/or impedance) at different high frequencies in advance with respect to an igniter assembly (measurement reference product) having a specific structure and serving as a measurement subject, confirming the frequency of a high frequency at which a magnitude relationship occurs between the high-frequency resistance values measured in relation to the first measurement circuit and second measurement circuit, and using this high frequency to measure the high-frequency resistances (pure resistances and/or impedances) of the first measurement circuit and second measurement circuit, it is possible to distinguish between the center pin (first electroconductive pin) and eyelet pin (second electroconductive pin) easily from the magnitude relationship between the high-frequency resistance values of the first measurement circuit and second measurement circuit.
[0044] After distinguishing between the two electroconductive pins (the center pin and eyelet pin) of the igniter assembly in this manner, the igniter assembly is incorporated into a known gas generator (for example, a gas generator used in a seatbelt pretensioner, disclosed in JP-A No. 2005-225274, or an air bag gas generator incorporated with an igniter assembly formed by integrating an igniter and a metallic collar by interposing resin therebetween, disclosed in FIGS. 1, 6 and 8 of JP-A No. 2001-16500), whereupon the gas generator is incorporated into an automobile safety device (for example, an air bag device or a seatbelt pretensioner) and installed in a vehicle. When an ignition power source (battery) is connected to the two electroconductive pins of the igniter assembly at this time, confusion between the positive and negative electrodes is eliminated. As a result, the reliability of the finally assembled automobile safety device is improved.
(2) Assembly Method and Distinguishing Method in FIG. 3
[0045] FIG. 3( a ) is a sectional view of an igniter assembly for illustrating an assembly method and a distinguishing method of the present invention, and a schematic view of high-frequency resistance measurement circuits including the igniter assembly. FIG. 3( b ) is an equivalent circuit diagram of high-frequency resistance measurement performed on the igniter assembly shown in FIG. 3( a ).
[0046] In FIG. 3( a ), an opening portion 37 of a metallic cap 36 is fixed to the metallic collar 30 of the igniter assembly 10 shown in FIG. 1 , and a molded body of gas generating agent 35 is charged into an interior space of the metallic cap 36 .
[0047] In high-frequency resistance measurement of a gas generator 50 , a first measurement circuit having the center pin 21 a as a terminal on one end side and the metallic cap 36 as a terminal on the other end side and a second measurement circuit having the eyelet pin 21 b as a terminal on one end side and the metallic cap 36 as a terminal on the other end side are formed. In these circuits, the resin 31 and the glass member 22 serve as dielectrics.
[0048] When a high frequency is introduced into the first measurement circuit (between the metallic cap 36 and the center pin 21 a ) by the high-frequency resistance measuring device 40 , the glass member 22 becomes a capacitor C 1 , the resin (the resin between the center pin 21 a and the metallic collar 30 ) 31 becomes a capacitor C 3 , the bridge wire 24 becomes a resistor R 1 (2Ω), and the metallic cap 36 , metallic collar 30 and center pin 21 a become non-resistive conductors.
[0049] Meanwhile, when a high frequency is introduced into the second measurement circuit (between the metallic cap 36 and the eyelet pin 21 b ) by the high-frequency resistance measuring device 40 , the glass member 22 becomes a capacitor C 1 , the resin (the resin between the eyelet pin 21 b and the metallic collar 30 ) 31 becomes a capacitor C 2 , the bridge wire 24 becomes a resistor R 1 (2Ω), and the metallic cap 36 , metallic collar 30 and eyelet pin 21 b become non-resistive conductors.
[0050] Hence, the first measurement circuit and second measurement circuit differ in the path along which the high frequency flows (in the first measurement circuit, the high frequency flows along the path of the capacitor C 3 , and in the second measurement circuit, the high frequency flows along the path of the capacitor C 2 ), and therefore also differ in high-frequency resistance (pure resistance and/or impedance). Therefore, when an appropriate high frequency is selected and measurement is performed at this high frequency, a magnitude relationship occurs between the measured high-frequency resistance values. The reason for this is that in the gas generator shown in FIG. 3( a ), the center pin 21 a and the eyelet pin 21 b bend in the same direction in respective parts thereof that are covered by the resin 31 , and in these resin 31 parts, the distance between the center pin 21 a and metallic collar 30 differs from the distance between the eyelet pin 21 b and metallic collar 30 . Hence, the capacitance of the capacitor C 3 differs from the capacitance of the capacitor C 2 .
[0051] Accordingly, by measuring the high-frequency resistance (pure resistance and/or impedance) at different high frequencies in advance with respect to an igniter assembly (measurement reference product) having a specific structure and serving as a measurement subject, confirming the frequency of a high frequency at which a magnitude relationship occurs between the high-frequency resistance values measured in relation to the first measurement circuit and second measurement circuit, and using this high frequency to measure the high-frequency resistances (pure resistances and/or impedances) of the first measurement circuit and second measurement circuit, it is possible to distinguish between the center pin (first electroconductive pin) and eyelet pin (second electroconductive pin) easily from the magnitude relationship between the high-frequency resistance values of the first measurement circuit and second measurement circuit.
[0052] After distinguishing between the two electroconductive pins (the center pin and eyelet pin) of the gas generator in this manner, the gas generator is incorporated into a known automobile safety device (for example, a pretensioner of a seatbelt retractor, disclosed in JP-A No. 2003-267186), whereupon the gas generator is incorporated into an air bag device (for example, a seatbelt pretensioner) and then installed in a vehicle. When an ignition power source (battery) is connected to the two electroconductive pins of the igniter assembly at this time, confusion between the positive and negative electrodes is eliminated. As a result, the reliability of the finally assembled automobile safety device is improved.
EXAMPLES
Example 1
Igniter Assembly of FIG. 2
[0053] The two measurement circuits (first measurement circuit and second measurement circuit) shown in FIGS. 2( a ) and 2 ( b ) were prepared, whereupon the pure resistance value (Ω) and impedance (Ω) were measured while varying the frequency, as shown in Tables 1 and 2. A “Network Analyzer, Model: 8753ES, Frequency Range: 30 kHz to 3 GHz”, manufactured by Agilent Technologies Inc., was used as the high-frequency resistance measuring device.
[0000]
TABLE 1
Pure Resistance(Ω)
First
Second
Frequency
measurement
measurement
(MHz)
circuit
circuit
Difference
3
202.500
233.500
−31.000
4
156.000
173.500
−17.500
5
116.000
134.130
−18.130
6
89.250
106.630
−17.380
7
73.130
86.500
−13.370
8
57.880
70.750
−12.870
9
45.690
58.190
−12.500
10
37.810
47.940
−10.130
15
8.880
16.690
−7.810
20
13.219
16.906
−3.687
30
8.188
9.313
−1.125
40
12.000
11.859
0.141
50
9.578
8.797
0.781
60
5.570
4.297
1.273
70
5.336
4.313
1.023
80
6.875
6.953
−0.078
90
7.938
8.914
−0.976
100
7.031
6.340
0.691
150
4.141
2.277
1.864
200
5.466
3.151
2.315
300
77.711
75.297
2.414
[0000]
TABLE 2
Impedance(Ω)
First
Second
Frequency
measurement
measurement
(MHz)
circuit
circuit
Difference
3
5435.074
5224.221
210.853
4
4108.962
3987.177
121.785
5
3296.841
3223.692
73.149
6
2757.245
2705.502
51.743
7
2365.631
2334.103
31.528
8
2074.208
2049.721
24.487
9
1844.666
1827.127
17.539
10
1662.430
1648.097
14.333
15
1110.636
1106.926
3.710
20
826.046
825.113
0.933
30
543.622
544.490
−0.868
40
399.520
400.176
−0.656
50
312.777
312.924
−0.147
60
254.551
254.406
0.145
70
209.048
208.295
0.753
80
170.549
168.573
1.976
90
136.701
133.059
3.642
100
127.624
126.030
1.594
150
48.491
47.547
0.944
200
14.943
15.883
−0.940
300
193.913
198.959
−5.046
[0054] As is evident from Tables 1 and 2, a magnitude relationship occurred clearly in both the pure resistance and the impedance between the first measurement circuit (between the resin cover 28 and the center pin 21 a ) and the second measurement circuit (between the resin cover 28 and the eyelet pin 21 b ) at each frequency. It is therefore possible to distinguish between the two electroconductive pins of the igniter assembly easily. Hence, confusion does not occur between the positive and negative electrodes of the ignition power source that is connected to the two electroconductive pins when incorporating the igniter assembly in a device, and the device can be assembled reliably and easily.
[0055] As shown in Tables 1 and 2, the measurement values of the pure resistance and impedance of the igniter assembly vary according to the frequency of the high frequency, and therefore, by selecting a high frequency at which the magnitude relationship between the respective measurement values of the first measurement circuit and second measurement circuit is comparatively large, and performing the measurement at this frequency, it is possible to distinguish between the center pin and the eyelet pin without influence from measurement errors.
Example 2
Gas Generator of FIG. 3
[0056] The two measurement circuits (first measurement circuit and second measurement circuit) shown in FIGS. 3( a ) and 3 ( b ) were prepared, whereupon the pure resistance value (Ω) and impedance (Ω) were measured while varying the frequency, as shown in Tables 3 and 4. A “Vector Network Analyzer, Model: ZVRE, Frequency Range: 10 kHz to 4 GHz”, manufactured by ROHDE & SCHWARZ, Inc. was used as the high-frequency resistance measuring device.
[0000]
TABLE 3
Pure Resistance(Ω)
First
Second
Frequency
measurement
measurement
(MHz)
circuit
circuit
Difference
10
188.560
185.810
2.750
15
111.750
106.750
5.000
20
81.969
79.437
2.532
30
48.156
47.031
1.125
40
36.625
35.516
1.109
50
28.578
27.156
1.422
60
22.906
21.109
1.797
70
19.703
18.383
1.320
80
17.102
16.086
1.016
90
15.148
14.273
0.875
100
14.000
13.109
0.891
[0000]
TABLE 4
Impedance(Ω)
First
Second
Frequency
measurement
measurement
(MHz)
circuit
circuit
Difference
10
1633.295
1601.979
31.316
15
1091.104
1063.054
28.050
20
828.691
809.123
19.568
30
560.857
549.356
11.501
40
421.799
411.310
10.489
50
335.653
327.107
8.546
60
276.437
270.199
6.238
70
232.448
227.033
5.445
80
198.717
193.886
4.831
90
171.725
167.378
4.347
100
149.488
145.612
3.876
[0057] As is evident from Tables 3 and 4, a magnitude relationship occurred clearly in both the pure resistance and the impedance between the first measurement circuit (between the metallic cap 36 and the center pin 21 a ) and the second measurement circuit (between the metallic cap 36 and the eyelet pin 21 b ) at each frequency. It is therefore possible to distinguish between the two electroconductive pins of the igniter assembly provided in the gas generator easily. Hence, confusion does not occur between the positive and negative electrodes of the ignition power source that is connected to the two electroconductive pins when incorporating the igniter assembly in a device, and the device can be assembled reliably and easily.
[0058] As shown in Tables 3 and 4, the measurement values of the pure resistance and impedance of the igniter assembly vary according to the frequency of the high frequency, and therefore, by selecting a high frequency at which the magnitude relationship between the respective measurement values of the first measurement circuit and second measurement circuit is comparatively large and performing the measurement at this high frequency, it is possible to distinguish between the center pin and the eyelet pin without influence from measurement errors.
[0059] As is evident from the high-frequency resistance measurement results shown in Tables 1 to 4, it is possible to distinguish between the two electroconductive pins of an igniter assembly (including a gas generator having an igniter assembly) by measuring either one of the pure resistance and the impedance. It is also possible to distinguish between the two electroconductive pins by measuring both the pure resistance and the impedance.
[0060] The invention 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 scoped of the invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims. | The present invention is a method of assembling a device employing electric ignition by comprising assembling an igniter assembly in the device, the igniter assembly having an electric igniter provided with a first electroconductive pin and a second electroconductive pin, connected to a power source, the method comprising steps of:
forming two measurement circuits by using the first electroconductive pin and the second electroconductive pin as a measurement terminal on one end side, respectively, and using another member provided in the igniter assembly as a terminal on the other end side with a pass through a dielectric provided in the igniter assembly, measuring pure resistances and/or impedances of the two measurement circuits, respectively, by applying a high frequency thereto separately, distinguishing the first electroconductive pin from the second electroconductive pin from a magnitude relationship (difference) between the measured pure resistance and/or impedance values, and then, disposing the igniter assembly to the device such that the first electroconductive pin and the second electroconductive pin correspond to predetermined power source electrodes, respectively. | 5 |
BACKGROUND OF THE INVENTION
Thyristors and other semi-conductor power components such as diodes, saturation-undergoing transistors and triacs, are usually dimensioned so as to be able, without the risk of being damaged, to withstand the maximum power they may happen to undergo momentarily. Accordingly, they are fairly oversized with respect to their normal operative power.
In some applications in which currents the value of which may be several times that of the normal operative current (e.g., start-up control, static or hybrid contactors) momentarily flow through the component, it might be an advantage, in order to prevent any oversizing of said component, to be able to obtain an accurate and continuous simulation of the junction temperature-rise, so as to actuate a safety member or an alarm signal whenever a reference temperature that is lower than the maximum temperature permissible is exceeded.
This problem has not yet been solved in a satisfactory manner.
In a semi-conductor power component comprising a housing and a radiator, it is possible, between the junction and the housing bottom, to determine a thermal resistance R jb , the value of which is given by the manufacturer. In the same way, it is possible to determine a thermal resistance R br between the housing and the radiator, the value of which can be provided by the manufacturer and a thermal resistance R ra between said radiator and the environment. The latter resistance, as well as R br when its value is not provided by the manufacturer, can be measured by sticking a thermocouple on the elements involved and applying the following formula: ΔT=P×R th , R th being the thermal resistance to be measured, P the transmitted power and ΔT the temperature difference between the element's extremities.
Such a measurement, in practice, cannot be made at the scale of a commercial manufacture, since it is difficult to mount the thermocouple in a stable manner unless an important mass is added, which considerably increases the thermal time-constant of the element measured.
It is however possible to carry out such a measurement in a laboratory on a sample of the component.
SUMMARY OF THE INVENTION
The present invention rests on the experimental discovery that the overall instantaneous thermal resistance of an electronic component of the above-mentioned type is approximately given by the following formula:
R.sub.th =R.sub.jb (1-e.sup.-t/τjb)+R.sub.br (1-e.sup.-t/τbr)+R.sub.ra (1-e.sup.-t/τra)
in which t designates the time and τ jb , τ br and τ ra are the time constants associated with thermal resistances R jb , R br and R ra respectively.
OBJECT OF THE INVENTION
The present invention lies in simulating the mean power dissipated by the component and in feeding the image signal of said power into the input of means adapted to simulate the overall instantaneous thermal resistance, in order to obtain an image signal of the temperature-rise undergone by said component.
Therefore, it is an object of the present invention to provide a simulating device comprising:
(a) of means for simulating the instantaneous intensity the current flowing through the component;
(b) means for simulating the mean current and the squared effective current from the image signal of the instantaneous intensity;
(c) means for summing the mean current and the squared effective current, with weighting coefficients representing maximum values guaranteed by the manufacturer, in order to simulate the mean power dissipated by the component;
(d) means for simulating the time-constants of the above-mentioned thermal resistances R jb , R br , R ra , the image signal of said mean power provided by the means under (c) being applied to the input of said means for simulating time constants and
(e) means for summing the image signals of the above-mentioned time constants, with weighting coefficients corresponding to the values (given by the manufacturer or previously measured) of said thermal resistances, in order to obtain an image signal of the temperature-rise undergone by the component.
It is known, in the case of a thyristor, that power P is connected to the mean current I m and to the effective current I eff by the following relation:
P=V.sub.o I.sub.m +R.sub.d I.sup.2.sub.eff
V o (threshold voltage) and R d (dynamic resistance) vary from one component to another in a given series; however, their maximum values, guaranteed by the manufacturer, will constitute the weighting coefficients referred to under (c).
In the case of other semi-conductor components of te above-mentioned type comprising a dynamic resistance mounted in series with a voltage drop (possibly nil), independent of the current, there exists equivalent coefficients provided by the manufacturer, e.g. V ce for saturation and R on for a transistor being saturated.
It is to be noted that the values of time constants τ jb , τ br and τ ra are quite different from one another, viz. about a fraction of a second as regards the first time-constant, a few seconds as regards the second one and between 50 and 1000 seconds as regards the third one.
While the first two time constants can be simulated by means of simple RC circuits, however it is not the case with the last time constant.
THE PRIOR ART
Accordingly, an important feature of the present invention consists, as regards simulating time constant τ ra , in applying a device of the type described in French patent filed by the applicant on Dec. 7, 1979, under Ser. No. 79 30094 and entitled "Dispositif de simulation d'un phenomene variable dans le temps avec une constante de temps elevee, notamment la temperature d'une charge electrique" (A device for simulating a time-variable phenomenon with a high time constant, in particular the temperature of an electric charge).
The device comprises a capacitor charged and/or discharged by an input voltage through a resistor and it is characterized by a chopper-switch in series with said resistor and by means for generating periodic pulses adapted to control said chopper-switch.
Other features and advantages of the present invention will appear from the following description given merely by way of example, with reference to the following drawing, in which
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram of a preferred embodiment of a temperature-rise simulating device according to the present invention;
FIG. 2 shows a preferred embodiment of the circuits for simulating the mean power;
FIG. 3 shows a preferred embodiment of the circuits for simulating the time constants and the temperature-rise image; and
FIG. 4 represents various waveforms in various portions of said circuits.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In FIG. 1 are shown a resistor R 1 adapted to convert intensity I in the component into a voltage U E and a circuit VA providing the absolute value kI of U E , k being a constant. The information is transmitted into a circuit VM for calculating mean value k 1 I m , on the one hand, and into a power-raising circuit EC adapted to calculate the square of effective value k 2 I 2 eff , on the other hand. (The latter circuit is associated with a time base BT).
The mean value and the squared effective value are fed into an adder S with weighting coefficients k 1 and k 2 permitting to obtain an image signal i (Pm) of the mean power dissipated. That signal is fed into the input of three circuits Kτ ra , Kτ br , Kτ jb simulating time-constants τ ra , τ br and τ jb , respectively, and actuated by a time base B 1 T 1 . As explained above, circuits Kτ br and Kτ jb can be of a conventional type with a capacitor-resistor, the third circuit being of the type described in the above-mentioned French patent.
The outputs of said three circuits are fed, with weighting coefficients corresponding to the above-mentioned three terminal resistances, into an adder S 1 , the output of which provides an image signal i (Δθ) of the temperature rise of the semi-conductor component junction.
The various functions described above can be carried out in the following way:
The current-intensity I in component SC can be read by means of a current-transformer T.I. (FIG. 2) and converted into a voltage U E by means of resistor R 1 .
The circuit VA for providing the absolute value is of a conventional type (rectifier without threshold).
The mean value VM circuit is constituted by an operational amplifier A 1 , the gain of which is determined by a divider constituted by resistors R 2 and R 3 .
Resistors R 4 and R 5 and a capacitor C 1 constitute a filter permitting to take the mean value of signal kI.
Time-base BT is a generator providing square signals with a low cyclic ratio actuating circuit EC, so as to set in the "on" state the monostable trigger unit M contained in EC, e.g. of the LM 555--type.
Monostable trigger unit M periodically discharges a capacitor C 2 , the latter being charged by a constant current by means of a transistor Q 1 .
The charge current is determined by a resistor R 6 and a base divider bridge constituted by resistors R 7 , R 8 and a diode D 1 . The latter diode is adapted to make up for the variations of the transistor base-emitter voltage with respect to temperature.
The voltage at the terminals of C 2 is fed (through a resistor R 9 ) into the positive input of a comparator A 2 , the output of which is switched whenever the voltage at said positive input is higher than voltage kI fed into the negative input through a resistor R 10 .
The positive-going edge of the input of A 2 is fed into plug 6 of M and causes capacitor C 2 to be discharged.
Capacitor C 2 will not be allowed to be charged until is formed a negative-going edge of time base BT (see FIG. 4).
A capacitor C 3 permits to improve stability.
Resistor R 11 is the load resistor of the comparator outlet stage.
The time-interval for charging capacitor C 2 is proportional to voltage kI, as well as its magnitude. The area of the triangle thus described is therefore proportional to the square of the current value. Said voltage is picked up by a divider-bridge R 12 R 13 and it is filtered by a capacitor C 4 , in order to be fed into an operational amplifier A 3 .
The output of operational amplifier A 3 , the gain of which is determined by a divider-bridge R 14 R 15 , is therefore proportional to the square of the effective current.
A operational amplifier A 4 , the gain of which is determined by a divider-bridge constituted by resistors R 16 , R 17 , receives, at its positive input, the output signals of A 3 and A 1 , duly weighted by resistors R 18 and R 19 respectively.
The output voltage of A 4 is thus the image of the mean power in the semi-conductor.
The junction-housing time constant τ jb is provided by a resistor R 20 and a capacitor C 5 charged by an operational amplifier A 5 , mounted as a follower.
The housing-radiator time constant τ br is provided by a resistor R 21 and a capacitor C 6 charged by an operational amplifier A 6 mounted as a follower.
The radiator-environment time constant τ ra is provided by a resistor R 22 and a capacitor C 7 and by a chopping device constituted by a time-base B 1 T 1 adapted to deliver square signals with a low cyclic ratio (e.g. 1/1000), the time period of which is about 1 second.
Said signals are adapted to control an analog switch CA 1 .
That device permits to multiply time constant R 22 ×C 7 artificially by the cyclic ratio of time-base B 1 T 1 .
The voltage at the terminals of capacitor C 7 is picked up by an operational amplifier A 7 , possibly of the field-effect transistor type, mounted as a follower.
A resistor R 23 permits to discharge capacitor C 7 through a second analog switch CA 2 , according to the initial conditions (diagramatically shown by rectangle CI).
The ouputs of the three follower stages A 7 , A 6 and A 5 are fed into an operational amplifier A 8 , via input resistors R 24 , R 25 , R 26 respectively.
These resistors determine the weight of each thermal resistance with respect to the overall thermal resistance.
R 27 is a gain resistor, R 28 is a resistor for compensating the drift current of amplifier A 8 .
The output amplifier A 8 is thus proportional in instantaneous value to the temperature rise of the semiconductor component junction.
For the time-range during which the validity of such a simulation is desired and for certain types of semiconductor components, it is possible to do without time-constant circuits τ jb and τ br , taking into account only the final value of the corresponding time constants.
In FIG. 1 is shown a sensor KTa for measuring room temperature Ta, said sensor being constituted e.g.; by a resistor with a negative temperature coefficient. The image current of Ta is added, in an adder S 2 , to the image current of temperature-rise Δθ in order to provide the image of the junction actual temperature. It is thus possible to use the component to the utmost, in particular whenever the room temperature is relatively low. | In order to simulate an instantaneous temperature-rise of a thyristor through which flows a current (I), this device takes the mean value (VM) of that current and squares the effective value (EC) thereof. An image of the dissipated power obtained at the output of an adder (S) is applied to devices (Kτra, Kτbr, Kτjb) for simulating radiator-environment, housing-radiator and junction-housing thermal time-constants, respectively. An adder (S 1 ) provides the image i (Δθ) of the temperature-rise. | 7 |
BACKGROUND OF THE INVENTION
The invention relates to an apparatus for drying animals, in particular horses, ponies or the like.
Animals, horses in particular, are often washed or showered. In particular horses used for sport have to be showered following the day's training. Then, in order to avoid chills, pneumonia or similar ailments, the horses have-to be dried carefully. It is essential here for this drying operation to take place not just on the surface of the back or the sides, but also beneath the belly in particular, this constituting a problem area.
Drying methods which have been known up until now have involved first of all moisture being stripped off horses using scrapers (the surface water is thus removed) and then the horses being covered by a sweat blanket. The problem area of the belly is thus not reached. The abovementioned method of drying involves considerable outlay and effort and therefore usually takes place merely to an insufficient extent.
The object of the invention, then, is to provide an apparatus by means of which animals, in particular horses, ponies or the like, can be dried easily, reliably, cost-effectively and carefully in a short period of time.
BRIEF SUMMARY OF THE INVENTION
An apparatus for achieving this object comprises a housing which has air-outlet openings on an underside and in which there are arranged at least one air-flow generator and at least one air-distributing means. Since a housing of the apparatus is provided with air-outlet openings on its underside, a compact apparatus is produced. This is because, in particular, the air-outlet openings may be an integral constituent part of the housing. Furthermore, the housing protects the air heaters arranged therein.
Moreover, the animals which are to be dried are protected from being influenced directly by the air heaters. At least one air-distribution means in the housing ensures that the hot air serving for drying purposes is distributed uniformly over all the air-outlet openings, which also results in the air passing out of the housing in a noise-free manner. It is important for the air to pass out in a noise-free manner in order that the animals do not develop a fear of drying and, instead, regard drying as a pleasant experience.
A further apparatus for achieving the object mentioned in the introduction comprises a housing, means arranged in the housing that are intended for generating an air stream, and air-outlet openings in an underside of the housing, air which passes out of the air-outlet openings forming, beneath the housing, a drying space for the animal which is to be arranged at least in part beneath the housing. By way of the drying space beneath the housing, in which the dry animal is arranged at least in part, the air serving for drying purposes reaches all the sides, to be precise even critical areas, of the animal without obstruction.
A preferred configuration of the invention provides for the or each air-distributing means to be arranged upstream of the air heaters, as seen in the flow direction. In this way, the air coming from the air-flow generators is guided past the air heaters in a uniformly distributed manner, as a result of which hot air passes out of the air-outlet openings in a uniformly distributed manner and at essentially the same temperature. This achieves uniform drying and, at the same time, prevents the situation where many areas of the animal which is to be dried in each case are dried with excessively cold air, which could lead to draughts and the animal suffering from ailments resulting therefrom. Uniform heating of the air makes it possible for the temperature of the hot air flowing out of the apparatus to be controlled reliably by a small number of temperature sensors or even just by one temperature sensor.
In the simplest case, the air-distributing means are designed as air-distributing plates which extend over all or some of the air heaters. The air-distributing plates have perforations for the through-passage of the air. The perforations are preferably formed for through-passage holes which are distributed uniformly over the surface of the air-distributing plates and have any desired cross section. The through-passage holes may be round, polygonal, oval or elliptical.
In a preferred configuration of the apparatus, the base wall of the housing is provided with different air-outlet openings. It is preferable for opposite longitudinal-border regions of the base wall of the housing to be provided with elongate air-outlet slits. It is sufficient if one air-outlet slit is provided in each of the two longitudinal-border regions of the base wall. The air-outlet slits generate, on opposite sides of the apparatus, sheet-like hot-air curtains which screen the hot air, in particular the hot air passing out of the air-outlet openings arranged between the air-outlet slits, from the ambient air, as a result of which it is possible for the animals to be dried from their back to their feet with hot air.
The air-outlet openings arranged in the region between the air-outlet slits of the base wall are preferably designed as air-outlet holes. The air-outlet holes are expediently distributed uniformly on the region of the base wall between the opposite air-outlet slits. The base wall of the housing is thus of sieve-like design between the elongate air-outlet slits. The air-outlet holes are dimensioned and spaced apart such that an essentially continuous veil of hot air passes out in the region of the air-outlet holes, that is to say between the elongate air-outlet slits, and fills the space between the lateral air curtains formed by the elongate air-outlet slits, with the result that the hot air can flow over the animal, from the apparatus, to the ground and the animal is dried completely in the process by a uniform hot-air stream. In this case, the hot air flows past the animal uniformly from top to bottom. Hot air which has accumulated moisture and has possibly been cooled can flow out via the air-curtain-free end sides of the drying space formed between the lateral air curtains.
In a preferred configuration of the invention, the air heaters are designed as convectors, to be precise plate convectors in particular. Such air heaters have proven successful in heating engineering. Plate convectors are suitable for use in the apparatus for drying animals, in particular, because their heat exchanger plates have a comparatively large surface area for heating the air flowing past it and, furthermore, the plates of the convectors help to even out and calm the air flow. It is preferably to provide a plurality of elongate plate convectors which are oriented parallel in the longitudinal direction of the apparatus and are arranged closely to one another without actually being in contact. This achieves uniform heating of the air over the entire region of the base wall of the apparatus. The base wall is located just beneath the adjacent convectors, as seen in the flow direction of the air, with the result that, once it has flowed past the convectors, the heated air can immediately flow up out of the apparatus without any significant energy losses.
The energy transfer medium (for example hot water) is fed to all the convectors via a common hot-water supply. For this purpose, in terms of flow, the convectors are arranged in parallel. However, it is also conceivable to provide a plurality of flow lines and thus for various groups of convectors arranged in parallel to be supplied with a heat transfer medium. For example, the convectors assigned to the elongate air-outlet slits may be assigned to a separate hot-water flow means, while the rest of the convectors, which are assigned to the air-outlet holes, may be supplied with heat energy jointly via a further hot-water flow means.
Cooled heat transfer medium is preferably discharged from the convectors in exactly the same way as hot heat transfer medium is fed. Further provision is made here for the supply to be assigned to a bottom half of the convectors, oriented towards the air-outlet openings, while the return is assigned to a top half of the convectors. This results in two-stage heating of the air, that is to say first of all preheating at the top, colder half of the convectors and then further heating at the bottom, hotter half of the convectors. The temperature difference between the air which is to be heated and the heat transfer medium in the convectors is evened out as a result, the top, cold air still being heated by the residual energy of the heat transfer medium in the convectors and better utilization of the heat energy of the heat transfer medium being achieved as a result.
It is conceivable for the convectors assigned to the air-outlet holes to be arranged wholly or in part in at least one chamber which forms surrounding upright side walls, connected to the base wall of the housing, around the convectors assigned to the air-outlet holes. This prevents air exchange with the convectors assigned to the lateral air-outlet slits, as a result of which the elongate air-outlet slits may be fed air, if appropriate, under a greater pressure in order to produce a more stable air curtain on opposite sides of the apparatus. In contrast, the air can pass out of the air-outlet openings at lower pressure, as a result of which this air, acting directly on the body of the animals, has a lower flow speed. This reliably avoids the situation where the animals are exposed to a draught.
Provision is further made for arranging one or preferably more air-flow generators, in particular fans, on or in the housing. The fans are preferably arranged on the top side of the housing, to be precise either within the same or outside on a top wall of the housing. Air taken in from the outside (cold air) is then fed directly into the housing by the fans. The number, size and power of the fans is adapted to the air pressure which is to produced in the interior of the housing and/or the speed at which the heated air serving for drying purposes flows out of the apparatus.
Alternatively, it is possible for the air-flow generators, in particular fans, to be arranged outside the housing, to be precise at a distance from the same. The air flow generated by the fans is then led into the housing via air-feed ducts such as pipes or tubes. This means that the fans may be placed in some other location, to be precise at such a distance away that only a very small amount of fan noise, if any at all, occurs in the region of the actual apparatus. The apparatus thus operates in a particularly noise-free manner, which means that the animals are not exposed to any significant noise development during drying. Such an apparatus is particularly suitable for frightened animals.
It is also conceivable to use other conventional air generators, for example compressors, in order to produce an air flow. On account of the fact that they develop more noise than fans, these compressors are always placed at a location remote from the apparatus, with the result that the air flow generated or else compressed air passes to the apparatus via a corresponding line system.
A preferred exemplary embodiment of the apparatus according to the invention is explained in more detail hereinbelow with reference to the drawing, in which:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a cross section through the apparatus,
FIG. 2 shows an end view of the apparatus without an end wall of a housing of the same,
FIG. 3 shows a side view of the apparatus,
FIG. 4 shows a plan view of the apparatus,
FIG. 5 shows a view of the apparatus from beneath,
FIG. 6 shows a planar blank of a base panel with air-outlet holes in a view from beneath analogous to FIG. 5,
FIG. 7 shows an enlarged cross section through the base panel of FIG. 6,
FIG. 8 shows a planar blank of a base panel with an elongate air-outlet slit in a view from beneath analogous to FIG. 5, and
FIG. 9 shows an enlarged cross section through the base panel of FIG. 8 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The apparatus shown in the figures serves for drying horses. The apparatus is suspended in space, to be precise at a level at which it is located at a small distance above the horse's back. The horse's head is thus located in front of the apparatus. The horse is centrally beneath the apparatus, to be precise in relation to a central longitudinal axis 10 of the apparatus (FIGS. 4 and 5 ).
The apparatus has a box-like housing 11 with parallel, upright side walls 12 , likewise parallel and upright end walls 13 , a curved base wall 14 and a curved top wall 15 . The base wall 14 and the top wall 15 are curved approximately equally in one direction, to be precise in the direction transverse to the longitudinal axis 10 , and this curvature is :such that it slopes up towards the centre. The base wall 14 thus has a concave curvature, as seen from an underside 16 . The top wall 15 runs approximately parallel to the base wall 14 . The concave curvature of the underside 16 of the base wall 14 means that the housing 11 is positioned part of the way round the horse from above.
The base wall 14 of the housing 11 is formed from base panels 17 and 18 which are arranged one beside the other without any gaps between them. The base panels 17 and 18 run continuously in the longitudinal direction of the housing 11 , that is to say they are aligned parallel to the longitudinal axis 10 . In the exemplary embodiment shown, the base wall 14 is formed from six inner base panels 17 and two outer base panels 18 . The two outer base panels 16 are arranged on opposite sides of the group of six inner panels 17 and thus form outer longitudinal-border regions of the housing 11 .
Each of the inner base panels 17 , which are of identical design, have a planar base surface and two parallel side surfaces 20 extending from opposite longitudinal borders of the base surfaces 19 . The parallel side surfaces 20 run at right angles to the base surface 19 and are oriented in the direction of the interior of the housing 11 (FIGS. 1 and 7 ). The entire base surface 19 of the base panel 17 , or at least most of said base surface, is provided with air-outlet openings, to be precise air-outlet holes 21 . The air-outlet holes 21 are distributed in a grid-like manner on the base surface 19 , as a result of which the latter has a sieve-like character. All the air-outlet holes 21 are of the same design. They have a round opening 22 which is then closed by a conical wall 23 . By way of the conical wall 23 , the openings 22 of the air-outlet holes 21 project downwards in relation to the underside 16 of the base wall 14 of the housing 11 . The distance between adjacent air-outlet holes 21 is approximately double the diameter of an opening 22 . The height of the frustoconical wall 23 is approximately half the size of the diameter of the opening 22 (FIG. 7 ).
The base panel 17 of FIG. 6 has two relatively large cylindrical holes 24 . Each of these holes 24 serves for receiving a built-in light 25 . In the exemplary embodiment shown, it is only the two outer base panels 18 which are provided with in each case two built-in lights 25 (FIG. 1 ). The four base panels 17 , located therebetween, do not have any built-in lights 25 . It is possible for the built-in lights 25 to be placed elsewhere in the base wall 14 of the housing 11 .
The outer base panels 18 are designed similarly to the base panels 17 . The base panels. 18 also have a planar, rectangular base surface 26 and two side surfaces 27 which are angled at right angles in relation to the borders of said surface. The side surfaces 27 are also oriented in the direction of the interior of the housing 11 . The base surface 26 of each base panel 18 has a single air-outlet opening, namely an elongate air-outlet slit 28 . Each air-outlet slit 28 runs parallel to the longitudinal axis 10 of the housing 11 , to be precise over virtually the entire length of the base surface 26 of the base panel 18 . The elongate air-outlet slits 28 are enclosed by a surrounding wall 29 , which extends perpendicularly to the plane of the base surface 26 . The wall 29 projects downwards in relation to the base surface 26 of the base panel 18 , and is thus oriented out of the housing 11 . Parallel, elongate side surfaces 30 , 31 of the wall 29 are of different lengths. The outer side surface 30 , which is oriented in the direction of the respective side wall 12 of the housing 11 , is longer than the inner side surface 31 , which is oriented in the direction of the longitudinal centre axis. A bottom, free border of the surrounding wall 29 thus encloses an elongate opening 32 of the air-outlet slits 28 , this opening running obliquely in relation to the plane of the base surface 26 , to be precise such that the angle of the plane of the opening 32 in relation to the side wall 12 of the housing 11 is more acute than the angle of the base surface 26 (FIGS. 1 and 9 ). By virtue of a mirror-inverted arrangement of the walls 29 of the air-outlet slits 28 of the opposite outer base panels 18 , the air curtains passing out of the opposite air-outlet slits 28 converge in the direction of the ground. The air curtains thus form a space which decreases in the direction of the ground and is intended for guiding the hot air passing out of the air-outlet holes 21 of the base panels.
The base panel 17 of FIG. 6 has two relatively large cylindrical holes 24 . Each of these holes 24 serves for receiving a built-in light 25 . In the exemplary embodiment shown, it is only the two outer base panels 17 which are provided with in each case two built-in lights 25 (FIG. 1 ). The four base panels 17 , located there between, do not have any built-in lights 25 . It is possible for the built-in lights 25 to be placed elsewhere in the base wall 14 of the housing 11 .
The apparatus also has a plurality of air heaters arranged in the interior of the housing 11 . In the apparatus shown here, the air heaters are designed as convector heaters, to be precise plate convectors 33 in particular. Each base panel 17 and 18 is assigned an elongate plate convector 33 . All the plate convectors 33 are designed identically to one another. Each plate convector 33 is arranged, and fastened, in the relevant base panel 17 or 18 , between the side surfaces 20 and 27 , respectively, of the same. The side surfaces 20 or 27 are of a length which extends approximately over half the height of the respective plate convector 33 and thus screens the bottom half of the same laterally and consequently forms chambers for receiving in each case one plate convector 33 . The plate convectors 33 are arranged in the base panels 17 and 18 such that undersides 34 of the plate convectors 33 terminate at a small distance above the base surfaces 19 or 26 of the base panels 17 , 18 , respectively (FIG. 1 ). In this case, the undersides 34 of the plate convectors 33 run parallel to the base surfaces 19 , 26 of the base panels 17 , 18 . The heat exchanger surfaces of the plate convectors 33 , said surfaces not being shown in the figures, run perpendicularly to the base surfaces 19 , 26 of the base panels 17 and 18 , to be precise transversely to the longitudinal axis 10 of the housing 11 .
All the plate convectors 33 have on an end side, in their bottom region, a connection stub 35 for a single flow line 36 . The flow line 36 is connected to the connection stubs 35 of all the plate convectors 33 . The same end surfaces of the plate convectors 33 , said end surfaces being oriented in the direction of an end wall 13 of the housing 11 , have, in their top region, in each case one further connection stub 37 for a common return line 38 . It is also the case that the connection stubs 37 of all the plate convectors 33 are connected to the single return line 38 . This means that all the plate convectors 33 are arranged in parallel. Via the flow line 36 , all the plate convectors 33 are supplied simultaneously in their bottom region with not-yet-cooled heat transfer medium, in particular hot water. This flows through the bottom region of all the plate convectors 33 . Arranged on the end sides located opposite the flow line 36 and the return line 38 are overflow lines (not shown in the figures) through which the hot water is led from a bottom half into the top half of the plate convectors 33 and, in the top half of the plate convectors 33 , flows back to the common return line 38 . From the latter, the cooled water is discharged in order to be reheated.
Arranged in the top wall 15 of the housing 11 are air-flow generators, these being fans 39 in the exemplary embodiment shown. In the present case, the apparatus has four fans 39 . In each case two fans 39 are spaced apart on different sides of the top wall 15 (FIG. 4 ). Arranged between the two fans 39 on each side of the top wall 15 is a partition wall 40 , which in the exemplary embodiment shown is of V-shaped design. The partition wall 40 subdivides the interior 41 of the housing 11 above the plate convectors 33 along the longitudinal axis 10 into two separate sub-areas 42 . In this way, the air flow generated by the two fans 39 of each half of the housing 11 cannot overflow from one half of the housing 11 to the other half. The fans 39 are arranged in the curved top wall 15 such that their rotating impellers 43 are located in a protected manner in the sub-areas 42 of the housing 11 . The rear side of the impellers 43 is provided with a protective grating 44 which covers the outside of the housing 11 and by way of which outside air is taken into the housing by the fans 39 . This air is led past the plate convectors 33 from the interior 41 and thus heated in stages, to be precise first of all in the top, colder part of the plate convectors 33 and then in the hotter part, located beneath the colder part, of the plate convectors 33 .
In the apparatus shown here, the interior 41 of the housing 11 is assigned air-distributing means above the plate convectors 33 . In the exemplary embodiment shown, said air-distributing means are two air-distributing plates 45 , of which one is accommodated in the respective sub-area 42 . In the exemplary embodiment shown, the air-distributing plates 45 , which are of identical design and are arranged in a mirror-inverted manner in the housing 11 , extend merely over the base panels 17 . In the present case, merely part, to be precise approximately two thirds, of the inner base panels 17 , which are adjacent on opposite sides of the longitudinal axis 10 , is covered over by the respective air-distributing plate 45 . The other two base panels 17 which follow on each side of the longitudinal axis 10 are covered over completely by the air-distributing plates 45 . The two outer base panels 18 , located opposite one another, with the elongate air-outlet slits 28 are not covered over by the air-distributing plate 45 . This is not necessary because, in the narrow elongate air-outlet slits 28 , the air is automatically distributed to the extent where a continuous air curtain is produced. In the case of the base panels 17 , which have a sieve-like grid of air-outlet holes 21 , the air-distributing plates 45 result in virtually the same quantity of air passing out of all the air-outlet holes 21 , to be precise even the border-side and end-side air-outlet holes 21 . This is achieved by perforations in the surfaces of the air-distributing plates 45 , the latter being formed, for example, from a perforated plate with a sieve-like arrangement of the uniformly distributed holes. The holes in the air-distributing plates 45 may have any desired surface areas.
The air-distributing plates 45 run parallel to the top side 46 of the plate convectors 33 , to be precise at a small distance therefrom in the exemplary embodiment shown. This achieves the situation where the air flowing through the sieve-arrangement holes in the air-distributing plates 45 is evened out again behind the air-distributing plates 45 in order to form a uniform veil of air which flows downwards in a rectified manner over the entire surface of the plate convectors 33 assigned to the base panels 17 . Rectified in this context means that the air flow everywhere has approximately the same pressure, the same flow direction and virtually the same flow speed.
In contrast to the exemplary embodiment shown, it is also conceivable for the air-distributing plates to be designed such that they cover over completely all the base panels 17 , provided with air-outlet holes 21 . It is likewise conceivable for the air-distributing plates 45 also to be arranged in the region of the outer base panels 18 with elongate air-outlet slits 28 .
The above described apparatus operates as follows:
Ambient air at room temperature is transported from the fans 39 in the top wall 15 into each of the two sub-areas 42 in the housing 11 . The quantity of air taken in is such that in the housing 11 , which, apart from the air-outlet holes 21 and the air-outlet slits 28 , is of air-tight design, a corresponding (slight) positive pressure builds up.
The air taken in passes, in particular in part, directly to the plate convectors 33 assigned to the outer base panels 16 with elongate air-outlet slits 28 . The air only passes to the rest of the plate convectors 33 once it has flowed through the holes of the sieve-design air-distributing plates 45 and has thus evened out on the underside of the air-distributing plates 45 , to be precise not just in terms of quantity, but also in terms of the flow direction, the flow speed and the pressure. Having passed the air-distributing plates 45 , the evened-out air passes to the plate convectors 33 assigned to the inner base panels 17 .
The air is heated in two stages on all the plate convectors 33 , that is to say first of all at the top half of the plate convectors 33 , which has returning hot medium flowing through it, and then in the bottom regions of the plate convectors 33 , which have inflowing and only slightly cooled heat transfer medium flowing through them. The heat exchanger plates of the plate convectors 33 likewise have an evening-out effect on the air flowing past the plate convectors 33 .
From the plate convectors 33 , the heated air passes into a narrow gap between the undersides 34 of the plate convectors 33 and the insides of the base wall 14 of the housing 11 . The heated air passes out through the opposite, outer air-outlet slits 28 of the base panels 18 and forms a hot-air curtain in the process. By virtue of the air-outlet slits 28 being positioned obliquely in the base panels 18 , the hot-air curtains are inclined slightly in relation to the vertical, to be precise such that the air curtains passing out of the opposite air-outlet slits 28 converge in the direction of the ground. This produces, between the two outer air curtains, a space which narrows in the direction of the ground. Said space serves as a drying space for the horse in each case. Drying space is applied with hot air which passes out through the air-outlet holes 21 of the base panel 17 . By virtue of the sieve-like design of the base surfaces 19 of the base panel 17 , a uniform veil of hot air passes out of the bottom of the housing 11 . By virtue of the air-outlet holes 21 being designed as nozzles which generate a diffuse hot-air curtain, the air passing out of the air-outlet holes 21 of the base panels 17 fill the drying space, formed between the hot-air curtains, beneath the housing 11 uniformly over the entire surface area. The hot air flowing out of the air-outlet holes 21 flows downwards, guided by the hot-air curtains on opposite longitudinal sides of the apparatus, and is accelerated in the process in the drying space, which narrows in the direction of the ground (as a result of the converging hot-air curtains), with the result that even in the region of the feet of the horse which is to be dried in each case there is still a hot-air flow speed which is sufficient for effective drying.
Since the drying space is only bounded by the hot-air curtains on opposite longitudinal sides of the apparatus, air can pass out of the drying space, formed between the hot-air curtains, by way of the end sides running transversely thereto. In this way, it is possible for air which has accumulated moisture and cooled to pass out of the drying space and for dry hot air to flow into the drying space, out of the air-outlet holes 21 , in its place.
The above described apparatus is also suitable for drying other animals such as ponies or the like.
Also, it can be seen by those of ordinary skill in the art that the abovedescribed apparatus may be sized larger or smaller to be suitable for drying animals of all sizes.
The above detailed description of the preferred embodiments and the appended figures are for illustrative purposes only and are not intended to limit the scope and spirit of the invention, and its equivalents, as defined by the appended claims. One skilled in the art will recognize that many variations can be made to the invention disclosed in this specification without departing from the scope and spirit of the invention. | Up until now, the task of rubbing animals, in particular horses, ponies or the like, dry once they have been washed (showered) has involved strenuous manual work. The effort involved in this rubbing-dry action means that the horses are often dried insufficiently and this results, in particular, in them catching chills. The invention proposes an apparatus for drying animals which has a housing ( 11 ) with air-outlet openings on the underside ( 16 ). The housing ( 11 ) is assigned fans ( 39 ), for generating an air flow, and air-distributing plates ( 45 ), as a result of which a uniform air stream is generated. This uniform air stream is heated by flowing along plate convectors ( 33 ) and then passes out of the housing ( 11 ) at the bottom as hot air through both air-outlet holes ( 21 ) and air-outlet slits ( 28 ). A hot-air flow generated in this way makes it possible for animals, in particular horses, to be dried carefully and effectively. | 0 |
BACKGROUND OF THE INVENTION
This invention relates to an encased product and method and apparatus for encasing same.
Presently known product encasing devices include a stuffing tube, a pump for pumping plastic product through the stuffing tube, a rotary chuck in front of the discharge end of the stuffing tube, linking apparatus for linking the filled casing, and looping apparatus for arranging the links in loops. As an addition to the use of a rotary chuck, some devices utilize a rotating stuffing tube which imparts rotation to the stuffed casing prior to the time that the casing is linked in the linking apparatus.
In these prior devices, a tubular casing is compressed in accordian-like fashion over the stuffing tube and includes one unfolded end protruding beyond the discharge end of the stuffing tube. As the product issues from the discharge end of the stuffing tube, it fills the portion of the casing protruding beyond the end of the stuffing tube, thereby filling the casing and propelling it away from the discharge end of the tube so that additional portions of casings will be unfolded and carried beyond the end of the tube.
The casings for making skinless franks, as well as edible casings for other kinds of sausage, are presently made in a tubular shape prior to being fitted over the end of the stuffing tube. Because of this tubular shape, it is difficult to treat the casing from both sides of the casing material. Also, in order to permit a substantial length of casing to be mounted on the tube, it is necessary to shirr the casing (wrinkle the casing so that it condenses into a short length) into a stick form so that a considerable length of casing can be placed on the horn, usually up to 100 feet or more. This shirring process is expensive and time-consuming, and the casing is bulky and in a fragile condition for shipping. During the stuffing and linking process these sticks or shirred casings are placed on a stuffing horn and rotated at a substantial speed to facilitate twisting of the casing at intervals after it has been filled in order to form links.
The above described method for placing the casing on the stuffing tube in shirred form, also has the disadvantage that the length of casing is somewhat limited. As each length of casing has been used up, it is necessary to shut down the machine so that an additional stick of shirred casing can be fitted over the stuffing tube.
It has been known that casings could be produced in a flat ribbon form and supplied in rolls which are thousands of feet in length. However, there has heretofore not been a convenient means for applying this casing to the stuffing tube in a form that will provide a cylindrical casing. This has been impractical prior to the present invention because the casing must be rotated in order to form a twisted link. Prior to the invention of application Ser. No. 644,218, filed Aug. 24, 1984, no practical means has been provided for applying the ribbon of casing to the stuffing tube, while at the same time permitting the casing to be rotated for forming the twisted link. However, the adhesive used in that invention and applied to the edges of the helically formed ribbon material, requires a very delicate and difficult operation.
Therefore, a primary object of the present invention is the provision of an improved encased product and method and apparatus for encasing same.
A further object of the present invention is the provision of an apparatus that will form a flat ribbon of casing material into a cylindrical casing while at the same time permitting the cylindrical casing to be filled with product, rotated and twisted into a plurality of sausage links, wherein the use of an adhesive on the ribbon is not required.
A further object of the present invention is the provision of an apparatus which will permit the forming of an elongated ribbon of casing material into a plurality of helical revolutions with the side edges of the ribbon within each one of the helical revolutions engaging and overlapping the side edges of the adjacent helical revolutions of the ribbon so as to form a cylindrical casing through the combined effect of inherent cohesiveness of the overlapped ribbon and the outward pressure of the material placed in the casing.
A further object of the present invention is the provision of apparatus which comprises a casing feed means which can be adjusted so as to change the angle of the helical revolutions at which the casing is wrapped around the stuffing tube.
A further object of the present invention is the provision of apparatus which will permit the formation of a cylindrical casing on a stuffing tube from a continuous strip of casing material regardless of whether or not the stuffing tube is stationary or rotating.
A further object of the present invention is the provision of apparatus which includes a stationary casing feed means, means for rotating the casing after it is filled, and linking means which grasps the rotating filled casing and permits the casing to twist and form a link.
A further object of the present invention is the provision of apparatus wherein the forward speed of the tubular casing is controlled by the linking mechanism and the rotating speed of the tubular casing determines the lateral or transverse movement of the casing ribbon.
A further object of the present invention is the provision of apparatus wherein the rotational speed of the casing and the longitudinal speed of the casing may be manipulated to produce a tubular casing of desired diameter and rotational speed so as to result in the desired number of helical revolutions of casing strip within each link and so as also to provide the desired length of sausage.
A further object of the present invention is the provision of apparatus which will reduce the cost of casings for forming sausage links.
A further object of the present invention is the provision of a method and an apparatus which will permit the forming of an elongated ribbon of casing material with the side edges thereof engaging and overlapping to form a cylindrical casing through the combined effect of inherent frictional cohesiveness of the overlapped ribbon and the outward pressure of the material placed in the casing wherein the cohesiveness is enhanced by the humidity or dampness of the ribbon.
A further object of the present invention is to provide a means for applying moisture to the ribbon as the ribbon is introduced into the product encasing machine.
A further object of the present invention is to provide a sealed cartridge containing ribbon to be used for encasing the product wherein a predetermined amount of humidity or moisture is imposed on the ribbon in the sealed cartridge wherein the humidity is maintained until the cartridge is opened for use in conjunction with the product encasing machine.
SUMMARY OF THE INVENTION
The present invention utilizes a product pump, a stuffing tube connected to the product pump, and linking means beyond the discharge end of the stuffing tube. In addition, a casing feed apparatus is mounted adjacent the stuffing tube, and is adapted to provide a flat ribbon form of casing material to the stuffing tube. The stuffing tube may be stationary or may be a rotatable stuffing tube. In the case of the stationary stuffing tube, additional means such as a rotating chuck are provided for rotating the casing after it is filled prior to the time that it reaches the linking apparatus. This rotational movement is supplied by the rotating stuffing tube in the case of a machine having a rotatable stuffing tube.
The casing ribbon is mounted on a casing feed apparatus which may be in the form of a rotating reel or other suitable form. The ribbon is fed from the reel onto the outer surface of the stuffing tube at an angle which is canted with respect to the longitudinal axis of the stuffing tube. The casing wrapped around the outer surface of the stuffing tube is rotated either by the rotating stuffing tube (in the case of a rotatable stuffing tube), or by other suitable means such as a rotating chuck (in the case of a stationary stuffing tube).
A product pump forces a product material through the stuffing tube and into the casing at the discharge end of the stuffing tube. This pulls the casing from the end of the stuffing tube and propels it toward the linking apparatus. Continuous actuation of the product pump causes the casing to be pulled off the end of the stuffing tube continuously and consequently cause the casing ribbon to be pulled continuously from the ribbon feed apparatus.
The ribbon feed apparatus introduces the ribbon to the outer surface of the tube at an angle canted with respect to the longitudinal axis of the tube. The rotating tube in the case of a rotatable tube (or the rotating chuck in the case of a stationary tube) causes the ribbon to be wrapped around the outer surface of the tube in a plurality of helical revolutions. The angle of the introduction of the ribbon to the tube and the width of the ribbon are chosen so that the edges of the ribbon overlap one another within the helical revolutions, thereby forming an elongated cylindrical casing. The overlapped edges of the casing strip are adhered to one another only by the inherent cohesiveness of the overlapped portions of the casing material and the pressure of the product to be encased so as to form a unitary cylindrical casing.
The preferred embodiment of the ribbon feed means comprises a reel mounted to a reel support frame for pivotal movement about both a horizontal axis and a vertical swivel axis. The reel is free to swivel freely about the vertical swivel axis so as to permit the reel to align itself with respect to the stuffing tube at a predetermined angle in response to the pulling of the ribbon from the reel. The angle of the reel with respect to the longitudinal axis of the stuffing tube may be altered by swinging the reel support frame about a second vertical axis with respect to the machine frame and by securing the reel support frame in a stationary position when the desired angle is achieved.
The stuffing tube shown in the present invention is of unique construction in that the discharge end of the stuffing tube has a plurality of radially outwardly extending fingers thereon. These outwardly extending fingers terminate in finger ends which engage the interior surface of the casing at a plurality of points. The distance between the finger ends is such that the casing is not stretched beyond its normal cylindrical circumference, but instead is deformed into a shape which in cross-section appears approximately in the form of a polygon with each of the fingers providing an apex of the polygon. These outwardly extending fingers provide a retarding effect or drag on the longitudinal movement of the casing as it is drawn off of the discharge end of the stuffing tube. This drag is important to insure the proper filling of the casing uniformly along the length of the casing.
The present invention utilizes a stationary mounting for the reel holding the casing ribbon, and still permits the casing to be rotated at the end of the stuffing tube so as to form the twisted links. In the case of a stationary stuffing tube, a rotating chuck or other means are provided adjacent the outlet end of the horn or tube for rotating the tubular portion of the casing at the proper speed to provide the desired number of twists per link. In the case of a rotating stuffing tube, the rotating tube itself imparts rotation to the casing on the tube.
Beyond the end of the stuffing tube is a linking device that pinches the casing together at controlled intervals to determine exactly where the twist will be established in the tubular casing as well as to space the distance between the links to determine the length of the sausage links.
The forward speed of the formed and filled tubular casing is controlled by the linking mechanism while the rotating speed of the tubular casing determines the speed at which the casing ribbon is drawn off of the ribbon feed means. By manipulating these two speeds, and by using the correct width of the ribbon, it is possible to produce a tubular casing of a desired diameter that is rotating at the proper speed so as to produce the number of twists desired per link and also so as to produce the desired length of sausage. These two motions combined together determine the angle at which the ribbon is applied to the horn. The free wheeling swivel mounting of the casing feed means allows the roll of casing to automatically swivel about a vertical swivel axis and follow the desired angle.
All of the foregoing aspects of the invention are shown in the above three identified prior patents. The novelty of of the instant invention is the application of sufficient humidity and moisture to the casing material to enhance the frictional cohesiveness of the overlapped portions thereof. The desired humidity can be imposed on the casing or ribbon material either at the time the material is introduced into the product encasing machine, or at the time of manufacture of the casing material wherein the casing material is placed in sealed cartridges to maintain the desired level of humidity until the time of usage.
BRIEF DESCRIPTION OF THE FIGURES OF THE DRAWINGS
FIG. 1 is a perspective view of the apparatus of the present invention.
FIG. 2 is a top plan view of the present invention.
FIG. 3 is a front elevational view of the present invention.
FIG. 4 is an enlarged perspective detail of the end of the stuffing tube.
FIG. 5 is a detailed sectional view showing the arrangement of the casing on the end of the stuffing tube.
FIG. 6 is a sectional view taken along line 6--6 of FIG. 5.
FIG. 7 is an enlarged sectional detail showing the inlet end of the stuffing tube.
FIG. 8 is a top plan view of the casing feed apparatus.
FIG. 9 is a sectional view taken along line 9--9 of FIG. 8.
FIG. 10 is an enlarged detail plan view of the discharge end of the stuffing tube and the linking means.
FIG. 11 is a sectional view taken along line 12--12 of FIG. 11.
FIG. 12 is a view similar to FIG. 10, but showing a modified form of the invention.
FIG. 13 is a partial perspective view of a portion of the stuffing tube as the ribbon material is being wound thereon.
FIG. 14 is a transverse sectional view taken on line 14--14 of FIG. 13.
FIG. 15 is a longitudinal sectional view taken on line 15--15 of FIG. 13.
FIG. 16 is a perspective view of a finished link of encased material.
FIG. 17 is a perspective view of a sealed cartridge containing the ribbon material of this invention.
FIG. 18 is a partial elevational view showing means for applying moisture to the ribbon or casing material as such material is being introduced into a product encasing machine.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1, the numeral 10 generally designates the stuffing and linking machine of the present invention. Machine 10 comprises a table or housing 12 having mounted on its upper surface a product pump assembly 14, a tube support assembly 16, a stuffing tube or horn 18, and a linking apparatus 20. Also mounted to table 12 is a casing ribbon feed assembly 22.
Referring to FIG. 7, product pump 14 is of conventional construction and therefore the details are not shown. Pump 14 includes an outlet 24 which is in communication with the inlet end 26 of stuffing tube 18. Tube support assembly 16 includes a housing 28 which is mounted on the upper surface of table or housing 12 and which includes a plurality of bearings 30 which support stuffing tube 18 and which provide rotatable mounting of stuffing tube 18 for rotation about a horizontal axis. A belt pulley 32 is mounted on stuffing tube 18 within housing 28. Trained around belt pulley 32 and around an additional motor pulley 34, is a drive belt 36. Motor pulley 34 is driven by a motor 38 so as to cause rotation of stuffing tube 18 about its longitudinal axis.
Stuffing tube 18 includes an enlarged diameter portion 40 adjacent its inlet end 26, and also includes an elongated reduced diameter portion 42 extending from enlarged portion 40 to the discharge end 44 of stuffing tube 18 (FIG. 4).
As can be seen in FIGS. 4 and 5, the discharge end 44 is provided with a plurality of fingers 46, each of which is flared radially outwardly to a finger tip 48. In the configuration shown in FIGS. 4 and 5, there are four fingers 46, but more or less fingers can be utilized without detracting from the invention.
As can be seen in FIG. 6, each of the finger tips 48 engage the interior surface of the casing 50 so as to cause the casing to have a substantially polygonal shape (in the case of the configuration shown in FIGS. 4 and 5, a square shape), rather than the circular cross-sectional shape which occurs around the reduced diameter portion 42 of stuffing tube 18. The outward flaring of tips 48 is chosen so that the tips do not deform or stretch the casing from its original natural shape attained by virtue of surrounding the stuffing tube 42. That is, the circumference of the casing 50 when it is engaged by finger tips 48, is the same and is not enlarged from the circumference of the casing 50 when it is surrounding the reduced diameter portion 42 of stuffing tube 18. Referring to FIG. 6, the dimension X represents the distance from the cross-sectional center of the stuffing tube to the outwardly tapered tips 48. If this distance X is chosen to be approximately 1.11 times the radius of the stuffing tube at reduced diameter portion 42, the result will be a deformation of the circular shape of the casing by fingers 48 without stretching or enlarging the circumference of the casing.
The result of the above configuration of outwardly flared fingers 46 is that a longitudinal drag is imparted to the casing so as to counteract the forward propelling motion imparted by the product exiting from the outward discharge end 44 of stuffing tube 18.
Casing ribbon feed assembly 22 is comprised of an elongated elbow frame 52 having an upper frame member 54 and a lower frame member 56 which are joined at an elbow 58. Upper frame member 54 is singular in construction. Lower frame member 56 is comprises of a pair of spaced apart arms 62. Spaced apart arms 62 and upper frame member 54 are joined to one another at elbow 58.
Rotatably mounted between spaced apart arms 62 is a casing reel 64 which is supported at elbow 58 by means of an axle pin 66 which extends through the center of reel 64. Pin 66 provides rotational mounting of reel 64 about a horizontal axis.
Wrapped around reel 64 is an elongated casing ribbon 68 which is flat and which includes opposite lateral edges 70, 72 (FIG. 13). Ribbon 68 is a cellulose material commonly used in sausage encasement. The thickness thereof is approximately 0.0012 inches and the width can vary, but a width of one to four inches is satisfactory.
The lower end of lower frame member 56 includes a vertically oriented bushing 74 (FIG. 9) which is positioned between two vertically spaced jaw members 76, 78 of a swing block 80. A pivot pin or bolt 82 extends downwardly through upper and lower jaws 78 and also through bushing 74 so as to provide pivotal mounting of elbow frame 52 about a vertical axis. As can be seen in FIG. 9, the length of bushing 74 is slightly greater than the thickness of lower frame member 56 so that frame member 56 will pivot freely about bushing 74 without binding against the upper and lower spaced apart jaws 76, 78.
Swing block 80 includes also a pair of spaced apart flanges 83, 84 which embrace a support block 86 rigidly mounted to table or housing 12. Swing block 80 is pivotally mounted to support block 86 by means of a bolt or pin 88 which extends through flanges 83, 84 and also extends through support block 86. Thus, swing block 80 is free to swing about the vertical axis provided by pin 88.
Rigidly mounted to the upper surface of support block 86 is an adjustment plate 89. Plate 89 is held against movement with respect to block 86 by means of bolts 92 and also by means of pin 88 which extends through plate 89.
Plate 89 includes an arcuate slot 90 therein which extends along a curve which is concentric to the pivotal axis provided by pin 88. Bolt 82 extends through slot 90 and thence downwardly through jaw members 76, 78 and bushing 84. When bolt 82 is tightened, it holds swing block 80 against pivotal movement about axis 88, while at the same time permitting elbow frame 52 to pivot freely or swivel freely about the vertical axis provided by pin 82. When it is desired to swing block 80 about axis 88, all that is necessary is to loosen bolt 82 and pivot the swing block 80 about pin 88 to the desired position. Bolt 82 is then tightened and the swing block 80 is held against further swinging movement.
Mounted on the upper end of upper frame member 54 is a ribbon support pin 94 (FIGS. 2 and 3). Pin 94 provides a sliding support surface for the ribbon 68 as it is pulled off of reel 64.
The free end of the ribbon as it passes off of reel 64 passes upwardly over pin 94 and then is wrapped around the stuffing tube 18 in a helical fashion so as to form an elongated cylindrical casing designated by the numeral 50. With reference to FIG. 15, each helix 68A comprises overlapped portions 68B and 68C. The amount of overlapping can vary, but it needs to be sufficiently great that the helixes 68A will not separate upon being filled with material. Overlapping equal to one-half the width of ribbon 68 is more than sufficient.
As can be seen in FIGS. 2 and 3, pin 94 is positioned forwardly of swivel pin 82. This arrangement places reel 64 and pin 94 on opposite sides of the swivel axis provided by pin 82. When ribbon 68 is pulled over pin 94 it causes the entire frame 52 to swivel freely about swivel pin 82 so as to self align the reel 64 with the angle of the ribbon helixes being formed on the stuffing tube.
The linking mechanism 20 is of conventional construction and includes a pair of rotating linking chains 100 having a plurality of V-shaped pinching members 102 and a plurality of V-shaped holding members 104 thereon. Chains 100 are mounted on spaced apart sprockets 106 and a pair of holding brackets 108 are positioned to hold the chains in spaced apart relationship so as to provide a link path 110 therebetween for receiving the rotating casing 50 from the discharge end of the stuffing tube 18 and for forming twisted links from the filled casing in conventional fashion.
The modification shown in FIGS. 1-12 includes a rotating stuffing tube 18. However, the present invention may also be utilized in combination with a stationary stuffing tube. FIG. 12 illustrates a modified form of the invention, wherein a stationary stuffing tube 110 includes adjacent its discharge end a rotating chuck assembly 112. Chuck assembly 112 is similar to rotating chucks presently used in product encasing machines. It includes a rotatable driven member 114 having a longitudinal chuck opening 116 with a plurality of flutes 118 protruding radially inwardly therefrom. Flutes 118 are adapted to engage the outer surface of the casing after it has been filled by product issuing from the discharge end of stuffing tube 110. The rotatable member imparts a rotation to the filled casing so that the casing is rotating at the time it is engaged by the linking mechanism 20.
The operation of the device shown in FIGS. 1-11 is as follows: The operator first determines the angle at which he wants the strip 68 to engage the stuffing tube 18. This is accomplished by loosening bolt 82 and pivoting swing block 80 within arcuate slot 92 to the desired angle. Bolt 82 is then tightened so as to prevent further movement of swing block 80. The free swiveling mounting of elbow frame 52 about pin 82 permits the reel 64 to swivel freely about the vertical axis of pin 82. This permits the reel 64 to self align by the action of the ribbon being pulled off the reel.
After choosing the correct setting for swing block 80, the operator pulls the loose end of ribbon 68 upwardly over pin 94 as shown in FIGS. 3 and 4. He then wraps the casing around the stuffing tube 50 in helical fashion as shown in FIG. 2 until a portion of the casing is protruding beyond the discharge end of the stuffing tube. As the operator pulls the ribbon off of reel 64, the overlapping portions 68B and 68C tend to frictionally adhere to each other to maintain the construction of the casing 50. Thus, when the ribbon is wrapped around stuffing tube 18, the lateral edges 70, 72 overlap and engage and frictionally adhere to one another and cause the ribbon to be formed into an elongated cylindrical casing designated by the numeral 50 in the drawings.
The operator next turns the machine on, causing the product pump 14 to force product through the stuffing tube and simultaneously causing the stuffing tube 18 to rotate. As the stuffing tube rotates, the friction between the stuffing tube and the cylindrical casing 50 causes the cylindrical casing 50 to rotate in unison with the stuffing tube. The product being pumped through the stuffing tube exits through the discharge end of the stuffing tube and fills the casing which is protruding beyond the stuffing tube so as to form a filled link which is engaged by the linking mechanism in conventional fashion as shown in FIGS. 10 and 11. The filling of the casing exerts an outward force against the helixes 68A and causes the overlapping portions 68B and 68C to more firmly engage and to frictionally adhere together.
The flared finger tips 48 engage the interior surface of the casing as it is being pulled off the discharge end of the stuffing tube, and provide a retardation or drag on the axial movement of the casing. This permits the casing to be at least partially filled prior to the linking operation. The lateral speed of the linking apparatus provides a final degree of filling as desired. The flared finger tips 48 also facilitate the rotation of the casing 50 in response to rotation of the stuffing tube.
The rotation of the stuffing tube and the axial movement of the cylindrical casing 50 from the discharge end of the stuffing tube causes the ribbon 68 to be continuously drawn off of reel 64 and wrapped helically around stuffing tube 18.
Because elbow frame 52 is permitted to swivel freely about the vertical axis of bolt 82, the reel 64 is permitted to align itself in a straight line with respect to the line between pins 82, 88.
If it is desired to change the location at which the ribbon is introduced to the rotating stuffing tube 18, the operator merely loosens bolt 82 and swings swing block 80 to the desired position. This will change the location of the reel relative to the stuffing tube so that the point at which the ribbon begins wrapping around the tube is also changed.
The angle of attack of ribbon 68 and the width of ribbon 68 are chosen so that the edges of the ribbon are adjacent or overlapping when wrapped around stuffing tube 18.
The result of the above construction is that the roll of casing is mounted on casing ribbon feed assembly 22 which is stationary with respect to the stuffing tube. At the same time, the present invention provides a rotating casing 50 at the end of the horn which is necessary in order to form the twisted links in combination with the linking mechanism 20.
The forward speed of the formed tubular casing 50 is controlled by the linking mechanism and by the speed at which the pump assembly 14 forces product from the end of the stuffing tube. The rotating speed of the tubular casing determines the lateral or transverse movement of the casing ribbon. Therefore, by manipulating these two speeds, and by using the correct width of ribbon, it is possible to achieve the desired angle of attack of the ribbon and to produce a tubular casing of desired diameter that is rotating at the proper speed to provide the desired number of twists per link and the desired length of each link.
In the modification shown in FIG. 12, the stuffing tube 110 is stationary and does not have a flared end. However, the rotation of the casing is provided by the rotating chuck assembly 112, which engages the filled casing adjacent the discharge end of the stuffing tube. This causes the casing to rotate on the stuffing tube, thereby producing the same effect of pulling the ribbon 68 off of feed assembly 22 and forming the helical convolutions which make up the cylindrical casing 50.
Thus, it can be seen that the present invention may be utilized with both a stationary stuffing tube or a rotating stuffing tube.
FIG. 17 shows an alternate form of the invention including a housing or cartridge 64A comprised of housing parts 64B and 64C sealed by any convenient means along seal line 64D. Cartridge 64D contains cartridge 64 wherein the ribbon 68 thereon has the desired level of humidity or moisture imposed thereon at the time of manufacture. The ribbon 68 is then sealed in cartridge 64D to maintain the moisture level in the ribbon until the ribbon is used as shown in FIGS. 1, 2 and 3.
FIG. 18 shows an attachment that can be made to the machine of FIGS. 1, 2 and 3 wherein humidity or moisture can be added to the ribbon 68 at the time that it is introduced into the product encasing machine. A roller 22A is mounted by any convenient means to the machine adjacent ribbon 68.
Roller 22A has a sponge-like material 22B secured to the outer surface and is mounted on a center rotational support 22C. The surface of the sponge-like material 22B is adapted to engage ribbon 68 as it emerges from reel 64 as shown in FIGS. 1, 2 and 3. A liquid or water-like supply tube 22D connected to a controlled sourced of liquid terminates adjacent the periphery of material 22B to deposit liquid on material 22B for subsequent deposit on ribbon 68. The liquid can be water or a water-based non-adhesive fluid.
The amount of moisture, or moisture content, to be imposed on ribbon 68 will vary depending on the precise material thereof. However, sufficient dampness must exist to permit the overlapping edges of the ribbon to experience sufficient frictional cohesiveness to maintain the casing strip in a self-contained tubular casing to contain a plastic product. The roller 22A can engage either the whole ribbon 68, or only the side edges which are overlapped.
Thus it is seen that this invention will achieve at least all of its stated objectives. | The encased product of the present invention comprises an elongated flexible casing cylindrically shaped substantially along its length and having opposite end closures. A product material fills the cavity formed by the flexible casing and maintains the casing in a cylindrical shape. The cylindrical casing is formed from a elongated strip of flexible material having opposite side edges, the strip being formed into a finished tubular casing with the side edges of the strip within each casing frictionally overlapping and engaging the side edges thereof. The product is formed by continuously applying an elongated flexible ribbon to the outer cylindrical surface of a stuffing tube at a canted angle with respect to the longitudinal axis of the tube and rotating the flexible ribbon at the point where it is applied to the stuffing tube so that it will wrap around the tube in a plurality of helical revolutions to form a cylindrical casing on the tube. The adjacent edges of the helical revolutions of the ribbon are frictionally overlapped to one another so as to form a cylindrical casing and product is forced through the tube from the rearward end to the discharge end and into the cylindrical casing. The stuffing tube may be a rotating stuffing tube or it may be a stationary stuffing tube. A ribbon feed device is provided for feeding a continuous strip of ribbon to the stuffing tube. Moisture is applied to the ribbon to enhance the cohesiveness of the overlapped side edges thereof. | 0 |
FIELD OF THE INVENTION
[0001] The present invention relates generally to the motion of liquids disposed on a surface with extremely small, predetermined surface features and, more particularly, to controlling flow resistance experienced by a liquid disposed on a surface with predetermined nanostructure or microstructure features
BACKGROUND OF THE INVENTION
[0002] Many beneficial devices or structures in myriad applications are characterized at least in part by having a liquid that is in contact with at least one solid surface. Recent applications have focused on the movement of small droplets of liquid disposed on nanostructured or microstructured surfaces which can be manufactured by various methods, such as various means of lithography or etching. Such surfaces result in surfaces that are useful for significantly reducing flow resistance experienced by droplets of liquid disposed on the surfaces.
[0003] One such application is described in “Nanostructured Surfaces for Dramatic Reduction of Flow Resistance in Droplet-based Microfluidics”, J. Kim and C. J. Kim, IEEE Conf. MEMS, Las Vegas, Nev., January 2002, pp. 479-482, which is hereby incorporated by reference herein in its entirety. That reference generally describes how, by using surfaces with predetermined nanostructure features, the flow resistance to the liquid in contact with the surface can be greatly reduced. The Kim reference teaches that, by finely patterning the surface in contact with the liquid, and using the aforementioned principle of liquid surface tension, it is possible to greatly reduce the area of contact between the surface and the liquid. It follows that the flow resistance to the liquid on the surface is correspondingly reduced. However, as exemplarily taught by the Kim reference, the flow resistance to the liquid is reduced to such a level that it was difficult or impossible to control the movement of the liquid. Thus, it was necessary to dispose the droplets in a narrow channel or other enclosure to control the freedom movement of the droplet to within a prescribed area.
[0004] In order to better control the movement of liquid droplets disposed on surfaces patterned with nanostructures or microstructures, more recent attempts have relied on characteristics of the droplet or, alternatively, intra-pattern characteristics of the nanostructures or the microstructures to control the lateral movement of liquid droplets. Such control is the subject of copending U.S. patent application Ser. No. 10/403,159, filed Mar. 31, 2003, entitled “Method And Apparatus For Variably Controlling The Movement Of A Liquid On A Nanostructured Surface” which is hereby incorporated by reference herein in its entirety. In one embodiment described in that application, the lateral movement of a liquid droplet is achieved by designing, illustratively, the size, shape, density, or electrical properties of the nanostructure or microstructure such that the contact angle of the leading edge of a droplet is made to be lower than the contact angle of the trailing edge of the droplet. The resulting force imbalance causes the droplet to move in the direction of the leading edge. In another embodiment, the droplet is caused to penetrate the feature pattern at a desired area such that it becomes substantially immobile. This penetration can be affected, for example, by changing the surface tension of the droplet, the temperature of either the droplet or the pattern or the voltage differential between the droplet and the feature pattern.
[0005] As described in the '159 application, one or both of the above embodiments may be useful in a variety of applications, such as, illustratively, a biological or micro-chemical detector, a chemical reactor, a patterning application, a tunable diffraction grating, a total internal reflection mirror, a microfluidic mixer, a microfluidic pump or a heat dissipation device.
[0006] Thus, the above-described prior efforts focused on either reducing flow resistance experienced by a droplet or controlling the movement of a droplet of water across a surface. In another recent attempt, nanostructures or microstructures are used to reduce the flow resistance experienced by a body moving through a fluid. That attempt is described in copending U.S. patent application Ser. No. 10/649,285, entitled “Method And Apparatus For Reducing Friction Between A Fluid And A Body,” filed Aug. 27, 2003 and is hereby incorporated by reference herein in its entirety. According to the embodiments of the invention disclosed in the '285 application, at least a portion of the surface of a vehicle moving through a fluid is patterned with nanostructures or microstructures. Thus, according to the principles discussed above, the flow resistance across the patterned surface is reduced. Also as discussed above, by causing the fluid to penetrate the patterned surface, flow resistance across the patterned surface can be increased.
SUMMARY OF THE INVENTION
[0007] While prior attempts to reduce the flow resistance of a fluid in contact with a surface are advantageous in many regards, we have realized that it would be extremely advantageous to be able to control the degree of penetration of a fluid disposed on a nanostructured or microstructured surface. Therefore, we have invented a method and apparatus wherein, in a first illustrative embodiment, a closed-cell nanstructured or microstructured surface is used in a way such that, when the pressure of at least a first fluid within one or more of the cells of said surface is decreased to or below a desired level, a droplet disposed on that surface is caused to at least partially penetrate the surface. In another illustrative embodiment, the pressure within one or more of the cells is increased to or above a desired level in a way such that the droplet of liquid is returned at least partially to its original, unpenetrated position. In this way, the penetration of the droplet into the surface can be varied to achieve a desired level of flow resistance experienced by the droplet of liquid.
[0008] In yet another embodiment, a closed-cell structure feature pattern is used to prevent penetration of the nanostructured or microstructured surface, even when the pressure of the fluid disposed on the surface is relatively high.
BRIEF DESCRIPTION OF THE DRAWING
[0009] FIGS. 1A, 1B , 1 C, 1 D and 1 E show various prior art nanostructure feature patterns of predefined nanostructures that are suitable for use in the present invention;
[0010] FIG. 2 shows an illustrative prior art device wherein a liquid droplet is disposed on a nanostructured or microstructured feature pattern
[0011] FIG. 3A shows the droplet of liquid of FIG. 2A suspended on the nanostructured feature pattern of FIG. 3 ;
[0012] FIG. 3B shows the droplet of liquid of FIG. 4A when it is caused to penetrate the nanostructured feature pattern of FIG. 3 ;
[0013] FIGS. 4A and 4B show an illustrative prior art device whereby the electrowetting principles are used to cause a liquid droplet to penetrate a nanostructure feature pattern;
[0014] FIGS. 5A, 5B and 5 C show a device in accordance with the principles of the present invention wherein a droplet is disposed in an initial position suspended on top of a nanostructured feature pattern ( FIG. 5A ), is caused to penetrate the feature pattern ( FIG. 5B ), and is then caused to return to a position suspended on top of the feature pattern ( FIG. 5C );
[0015] FIGS. 6A and 6B show an illustrative closed-cell structure in accordance with the principles of the present invention;
[0016] FIGS. 7A and 7B show the detail of one cell in the illustrative structure of FIGS. 6A and 6B ;
[0017] FIGS. 8A, 8B and 8 C show a device in accordance with the principles of the present invention wherein a droplet is disposed in an initial position suspended on top of a nanostructured feature pattern ( FIG. 8A ), is caused to penetrate the feature pattern ( FIG. 8B ), and is then caused to return to a position suspended on top of the feature pattern ( FIG. 8C );
[0018] FIG. 9 shows a graph of the temperature of the fluid in a closed cell necessary to achieve a transition from the device in FIG. 5A to the device in FIG. 5B as a function of the initial temperature in that cell and the size d of the cell;
[0019] FIG. 10 shows a graph of the temperature of the fluid in a closed cell necessary to achieve a transition from the device in FIG. 5B to the device in FIG. 5C as a function of the initial temperature in that cell and the size d of the cell;
[0020] FIGS. 11A and 11B show another embodiment of a closed-cell structure in accordance with the principles of the present invention;
[0021] FIG. 12 shows a graph of pressure versus cell dimensions for the embodiment of FIGS. 11A and 11B ;
[0022] FIGS. 13A and 13B show another embodiment of a closed-cell structure in accordance with the principles of the present invention;
[0023] FIG. 14 shows a graph of pressure versus cell dimensions for the embodiment of FIGS. 11A and 11B .
DETAILED DESCRIPTION
[0024] As described above, microstructures and nanostructures have been used recently to reduce the flow resistance of experienced by a liquid as it moves across a surface. Such prior micro- or nanostructures can take many forms. For example, FIGS. 1A-1E show different illustrative prior art arrangements of nanoposts produced using various methods and further show that such various diameter nanoposts can be fashioned with different degrees of regularity. These figures show that it is possible to produce nanoposts having various diameters separated by various distances. An illustrative method of producing nanoposts, found in U.S. Pat. No. 6,185,961, titled “Nanopost arrays and process for making same,” issued Feb. 13, 2001 to Tonucci, et al, is hereby incorporated by reference herein in its entirety. Nanoposts have been manufactured by various methods, such as by using a template to form the posts, by various means of lithography, and by various methods of etching. As used herein, unless otherwise specified, the terms nanostructures/nanoposts and microstructures/microposts are used interchangeably. Throughout the description herein, one skilled in the art will recognize that the same principles applied to the use of nanoposts or nanostructures can be equally applied to microposts or other larger features in a feature pattern.
[0025] As is noted by the Kim reference described hereinabove, prior attempts at placing a droplet on surfaces having nanostructures or microstructures were problematic, as the extremely low flow resistance experienced by the droplet made it almost impossible to keep the water droplets stationary on the respective surface. As shown in FIG. 2 , the reason for this low flow resistance is that the surface tension of droplet 201 of an appropriate liquid (depending upon the surface structure) will enable the droplet 201 to be suspended on the tops of the nanostructure feature pattern 202 with no contact between the droplet and the underlying solid surface 203 . While nanostructures 202 are illustratively cylindrical posts in FIG. 2 , one skilled in the art will realize that many suitable geometric shapes, such as conical posts, may be equally advantageous. As illustratively shown in FIG. 2 , suspending the droplet on top of the nanostructures results in an extremely low area of contact between the droplet and the nanostructured surface 204 (i.e., the droplet only is in contact with the top of each post 202 ) and, hence low flow resistance.
[0026] FIG. 3A shows a macro view of the droplet 201 of FIG. 2 when it is suspended on top of the nanostructure feature pattern 202 . As in FIG. 2 , the droplet in FIG. 3A does not penetrate the feature pattern 202 and, accordingly, experiences a low flow resistance. FIG. 3B , however, shows illustrative droplet 201 in a configuration in which it does penetrate feature pattern 202 . When the droplet 201 penetrates the feature pattern 202 , the droplet becomes relatively immobile, i.e., it experiences a relatively high degree of flow resistance. In general, a liquid droplet will penetrate a feature pattern, for example, when the surface tension of the liquid droplet is sufficiently low. Therefore, depending upon the characteristics of the feature pattern 202 , one skilled in the art will be able to select a liquid for droplet 201 with an appropriate surface tension to facilitate such penetration of the pattern 202 . Alternatively, as described in copending U.S. patent application Ser. No. 10/403,159, discussed and incorporated by reference hereinabove, various methods can be used to reduce the surface tension of the droplet 201 that is suspended on top of the feature pattern, as is illustrated in FIG. 3A .
[0027] FIGS. 4A and 4B show such a prior art embodiment of one method useful to cause the droplet 201 to penetrate a nanostructure feature pattern. FIG. 4A illustrates, for example, the area 301 in FIG. 3 of droplet 201 in contact with feature pattern 202 . Referring to FIG. 4A , droplet 201 is illustratively a conducting liquid and is disposed on nanostructure feature pattern 202 of conical nanposts. As described above and illustrated in FIG. 3A , the surface tension of the droplet 201 is such that the droplet 201 is suspended on the upper portion of the feature pattern 202 . In this arrangement, the droplet 201 only covers surface area f 1 of each nanopost. The nanoposts of feature pattern 202 are supported by the surface of a conducting substrate 203 . Droplet 201 is held illustratively at an electrical potential difference with respect to substrate 203 , applied by voltage source 401 through lead 402 .
[0028] FIG. 4B shows that, by applying a low voltage (e.g., 10-20 volts) to the conducting droplet of liquid 201 , a voltage difference results between the liquid 201 and the nanoposts of feature pattern 202 . As a result, the contact angle of droplet 201 decreases and droplet 201 moves down in the y-direction along the surface of the nanoposts and penetrates the nanostructure feature pattern 202 until it completely surrounds each of the nanoposts and comes into contact with the upper surface of substrate 203 . In this configuration, the droplet covers surface area f 2 of each nanopost. Since f 2 >>f 1 , the overall contact area between the droplet 201 and the nanoposts of feature pattern 202 is relatively high and, accordingly, the flow resistance experienced by the droplet 201 is greater than in the embodiment of FIG. 4A . Thus, as shown in FIG. 4B , the droplet 201 effectively becomes stationary relative to the nanostructure feature pattern in the absence of another force sufficient to dislodge the droplet 201 from the feature pattern 202 .
[0029] The present inventors have recognized that it would be desirable to be able to selectively cause a droplet of liquid to penetrate a feature pattern and, then, to be able to selectively reverse this penetration. FIGS. 5A, 5B and 5 C illustrate such a selective/reversible penetration of droplet 501 into pattern 504 . FIG. 5A shows an illustrative droplet 501 disposed on a nanostructure or microstructure feature pattern 504 that is supported by substrate 505 . The angle of contact between the droplet and the feature pattern is shown as θ 1 . Next, as shown in FIG. 5B and discussed above, droplet 501 is caused to penetrate the feature pattern 504 . The angle of contact between the droplet and the feature pattern increases in this case to θ 2 as the droplet moves down along the individual elements (e.g., nanoposts) toward substrate 505 . Finally, as shown in FIG. 5C , it is desirable to reverse the penetration of droplet 502 into the pattern 504 . In this case the contact angle between the droplet and the feature pattern is as low or lower than θ 1 . Here, illustratively, the contact angle between the droplet 501 and the feature pattern 504 is shown as θ 3 , which is illustratively a smaller angle than θ 1 .
[0030] FIGS. 6A and 6B show, respectively, a three-dimensional view and a top cross-sectional view of an illustrative feature pattern in accordance with the principles of the present invention that is capable of accomplishing the reversible penetration shown in FIGS. 5A-5C . Specifically, in the present illustrative embodiment represented by FIGS. 6A and 6B , the feature pattern does not comprise a number of posts spaced a distance away from each other. Instead, a number of closed cells, here illustrative cells of a hexagonal cross section, are used. As used herein, the term closed cell is defined as a cell that is enclosed on all sides except for the side upon which a liquid is or could be disposed. One skilled in the art will recognize that other, equally advantageous cell configurations and geometries are possible to achieve equally effective closed-cell arrangements. FIGS. 7A and 7B show a top cross-sectional view and a side view of an illustrative individual cell of the feature pattern of FIGS. 6A and 6B . Specifically, referring to FIG. 7A , each individual cell 701 is characterized by a maximum width 702 of width d, an individual side length 703 of length d/2 and a wall thickness 704 of thickness t. Referring to FIG. 7B , the height 705 of cell 701 is height h.
[0031] FIGS. 8A, 8B and 8 C show how an illustrative closed-cell feature pattern similar to the feature pattern of FIGS. 6A and 6B , here shown in cross-section, may be used illustratively to cause a droplet 801 of liquid to reversibly penetrate the feature pattern. Specifically, each cell within feature pattern 804 , such as cell 701 having a hexagonal cross-section, is a completely closed cell once the droplet of liquid covers the opening of that cell. Thus, referring to FIG. 8A , each such closed cell over which the droplet is disposed contains a fluid having an initial temperature T=T 0 and an initial pressure P=P 0 . As used herein, the term fluid is intended to encompass both gases (such as, illustratively, air) and liquids that could be disposed within the cells of the feature pattern. The present inventors have recognized that, by changing the pressure within the individual cells, such as cell 701 , the liquid droplet 801 can be either drawn into the cells or, alternatively, repelled out of the cell. Specifically, referring to FIG. 8B , if the pressure within the cell 701 is caused to be below the initial pressure (i.e., P<P 0 ), then the contact angle of the droplet with the feature pattern will increase from θ 1 to θ 2 and the droplet above that cell will be drawn into the cell a distance related to the magnitude in reduction of the pressure P. Such a reduction in pressure may be achieved, illustratively, by reducing the temperature of the fluid within the cells such that T<T 0 . Such a temperature reduction may be achieved, illustratively, by reducing the temperature of the substrate 805 and/or the feature pattern 804 . In this illustrative example, the temperature of the fluid may be reduced by well-known conduction/convection principles and, accordingly, the pressure within the cell will drop. One skilled in the art will recognize that any method of reducing the pressure within the cells, including any other method of reducing the temperature of the fluid within the cells, will have similar results.
[0032] FIG. 8C shows how, by increasing the pressure to or above the initial pressure P 0 , it is possible to reverse the penetration of the droplet 801 . Once again, such a pressure increase may be achieved by changing the temperature of the fluid within the cells, illustratively in FIG. 8C to a temperature greater than the initial temperature T 0 . The increased temperature will increase the pressure within the cells above the initial pressure P 0 . The contact angle between the droplet and the elements of the feature pattern will thus change to θ 3 , which is smaller than θ 1 and the liquid will move out of the cells, thus returning droplet 801 to a very low flow resistance contact with feature pattern 804 . Once again, one skilled in the art will recognize that any method of increasing the pressure within the cells to reverse the penetration of the droplet 801 , including any other method of increasing the temperature of the fluid within the cells, will have similar results.
[0033] FIG. 9 shows a graph 904 of the temperature (T trans ) necessary to achieve a 120 degree contact angle of advancement (θ 2 in FIG. 8B ) in order to achieve penetration of the droplet into a feature pattern. FIG. 9 assumes a cell height h of 160 microns and a droplet interfacial tension of 62 mN/m. With these conditions, FIG. 9 shows that, for an initial temperature T 0 of the fluid within the cells and for a representative width d (represented by plots 901 , 902 and 903 and shown in FIGS. 7A and 7B as dimension 702 ), there is a given temperature (T trans ) at or below which a droplet will penetrate the feature pattern. For example, If the width of the cell is 15 microns, illustrated by plot 902 on graph 904 , and the initial temperature T 0 of the fluid in the cells is 60 degrees Celsius, then the pressure will drop sufficiently to cause the droplet to penetrate the feature pattern at or below a transition temperature T trans of approximately 15 degrees Celsius, represented by point 905 on plot 902 .
[0034] FIG. 10 shows a graph 1004 having plots 1001 , 1002 and 1003 representing different cell widths d, discussed above. Once again, the interfacial tension of the droplet is assumed to be 62 mN/m and the cell height h is assumed to be 160 microns. FIG. 10 shows the temperature change necessary to achieve a 0 degree contact angle (θ 2 in FIG. 8B ) which is the smallest contact angle theoretically achievable to reverse the penetration of the droplet after it has penetrated the feature pattern. For example, once again for a cell width of 15 microns, represented by plot 1002 , for an initial temperature T 0 (prior to any penetration of the feature pattern) of 40 degrees Celsius, point 1005 on plot 1002 shows that a transition temperature T trans of approximately 110 degrees Celsius is necessary to increase the pressure within the cells and reverse the contact angle of the droplet to 0 degrees and achieve full reversal of the penetration. One skilled in the art will recognize that different contact angles may be achieved and, in the case of reversing the penetration, lower transition temperatures will generally result in greater contact angles, all else remaining equal. Thus, many different temperatures (lower than T 0 ) may be used to penetrate the liquid into the feature pattern and, similarly, many different temperatures (higher than T 0 ) may be used to reverse that penetration.
[0035] Thus, the foregoing discussion illustrates how penetration of a feature pattern may be achieved and how that penetration can be selectively reversed. However, in addition to facilitating penetration reversal, the present inventors have recognized that closed cell feature patterns such as that described above, are useful for other purposes. For example, such feature patterns may function to substantially prevent any penetration of the feature pattern even in the presence of increasing pressure exerted by the droplet onto that feature pattern. Such a function may be desirable on, for example, a submersible vehicle. The use of above-described open-celled nanostructured feature patterns on submersible vehicles is the subject of copending U.S. patent application Ser. No. 10/649,285, entitled “Method And Apparatus For Reducing Friction Between A Fluid And A Body,” filed Aug. 27, 2003, which is hereby incorporated by reference herein in its entirety.
[0036] The '285 application discloses how open-celled nanostructure feature patterns, when used on a submersible vehicle such as a submarine or a torpedo, will dramatically reduce the friction (drag) caused by flow resistance of, illustratively, water passing across the surface of the underwater vehicle. However, while such reduced friction is advantageous in many situations, the present inventors have recognized that, when the pressure of the water exceeds a certain threshold (depending upon the characteristics of the feature pattern), the water will penetrate the feature pattern, possibly dramatically increasing the drag on the submersible vehicle. Therefore, the present inventors have further recognized that it is desirable to prevent the water from penetrating the feature pattern even in the presence of relatively high pressure.
[0037] FIGS. 11A and 11B show one illustrative embodiment in accordance with the principles of the present invention whereby liquid is prevented from penetrating a feature pattern even when that liquid is at a relatively high pressure. Referring to FIG. 11A , a top view of a nanostructured or microstructured feature pattern is shown wherein each cell has a rectangular cross section. Each cell has a length l, a wall thickness t and a width r. Referring to FIG. 11B , each cell also has a height h. Illustratively, l=10 micrometers, t=0.3 micrometers, r=4 micrometers and h=0.25 micrometers. Initially, the pressure within each of the cells in FIG. 11A is at an ambient pressure P 0 . Thus, for example, in the case where the feature pattern of FIGS. 11A and 11B is disposed on the surface of a submarine, when the submarine is traveling on the surface of water at least a portion of the cells will have an initial pressure of the air surrounding the submarine. When the submarine submerges, however, as is illustratively represented by FIG. 11B , the water begins to exert a pressure P 2 onto the feature pattern, thus resulting in a contact angle θ between the liquid and the pattern. The resulting increased contact angle will correspondingly increase the pressure of the fluid (e.g., air) within the cell from P 0 to P 1 . As the depth of the submarine increases and the pressure P 2 increases, the contact angle θ will increase and, as a result, the pressure P 1 within the cell will similarly increase. At a threshold determined by the characteristics of the feature pattern 1103 (e.g., the length, height and width of the cells), the pressure P 2 and hence the contact angle θ will become too great and the water 1102 will penetrate the feature pattern 1103 until it contacts substrate 1101 . For the feature pattern of FIGS. 11A and 11B , therefore, up to a certain pressure limit there will be a range of pressures (that correspond to depths in water for the illustrative example of a submarine) for which the water will not penetrate the feature pattern. Thus, in the case of the submarine, the submersible vehicle can submerge to a depth much greater without penetration of the feature pattern than would be the case where an open-celled feature pattern of, for example, nanoposts, were used. As a result, low flow resistance can be maintained to a much greater depth that using such an open pattern.
[0038] FIG. 12 shows a graph 1204 with plots 1201 , 1202 and 1203 that illustrate how different pressures within the cells of the feature pattern of FIGS. 11A and 11B will result in a specific contact angle when the cells are defined by a particular height to width ratio (h/r). For example, plot 1201 shows that, for cells having h/r=0.18, a pressure P 1 that is two times the initial pressure P 0 will result in a contact angle of 120 degrees. Plots 1202 and 1203 show how changes in the pressure P 1 will result in different contact angles for given cell dimensions. One skilled in the art will readily be able to develop different plots for different contact angles other than those shown in FIG. 12 .
[0039] FIG. 12 also shows that, for pressures and cell dimension combinations that fall within area 1205 of graph 1204 , there are no solutions that would lead to an unpenetrated surface of the feature pattern. Thus, for example, for any cell dimensions, a pressure P 1 that is 5 times the initial ambient pressure P 0 , will lead to penetration of the feature pattern. However, since such pressures are routinely experienced by underwater vehicles such as submarines, it is highly desirable to be able to prevent penetration of the feature pattern for significantly greater pressures.
[0040] FIGS. 13A and 13B show an illustrative cell configuration that will prevent the penetration of water into the feature pattern at significantly greater pressures. As shown in FIG. 13A the top cross section view of the feature pattern capable of withstanding greater pressures appears to be the same as that in FIG. 11A and, indeed, can have the same length (l=10 micrometers), wall thickness (t=0.3 micrometers) and width (r=4 micrometers) as the embodiment in that figure. Similarly, referring to FIG. 13B , the height of the individual cells is, illustratively, the same as the height h (0.25 microns) of the cells of FIG. 11B . FIG. 13B shows, however, that instead of being rectangular in side cross section, as were the cells in FIG. 11B , the cells of 13 B are rounded at the bottom and, thus, each cell is capable of holding less fluid (e.g., air). As a result, when the pressure P 2 rises and compresses the fluid within the cell, the pressure P 1 rises more quickly than was the case in the embodiment of FIGS. 11A and 11B . Thus, the cell can withstand a much higher pressure of water before the liquid will penetrate the cells of the feature pattern.
[0041] FIG. 14 shows a graph 1404 with plots 1401 , 1402 and 1403 that illustrate how different pressures within the cells of the feature pattern of FIGS. 13A and 13B will result in a specific contact angle when the cells are defined by a particular height to width ratio (h/r). As can be seen at point 1405 , for a height to width ratio of approximately 0.12, a contact angle of approximately 110 degrees will result from a pressure P 1 of 5 times the initial ambient pressure P 0 . Similarly, point 1406 shows that, for a slightly higher cell height to width ratio of 0.18, a contact angle of 120 degrees will result from a pressure P 1 of 6 times the initial ambient pressure P 0 . In fact, a contact angle of 120 degrees is practically limitless with regard to the pressure P 1 that can be withstood without penetration of the feature pattern. Accordingly, the low-flow properties of the surface remain intact and, in the case of a submarine, a low friction (drag) will continue to be experienced even at great water pressures/depths.
[0042] The foregoing merely illustrates the principles of the invention. It will thus be appreciated that those skilled in the art will be able to devise various arrangements which, although not explicitly described or shown herein, embody the principles of the invention and are within its spirit and scope. Additionally, one skilled in the art, in light of the descriptions of the various embodiments herein, will recognize that the principles of the present invention may be utilized in widely disparate fields and applications. For example, one skilled in the art will recognize that, although not explicitly described hereinabove, other well known methods of producing nanostructures or microstructures, such embossing, stamping, printing, etc., could be used.
[0043] All statements herein reciting aspects and embodiments of the invention, as well as specific examples thereof, are intended to encompass functional equivalents thereof. Moreover, all examples and conditional language recited herein are intended expressly to be only for pedagogical purposes to aid the reader in understanding the principles of the invention and are to be construed as being without limitation to such specifically recited examples and conditions. For example, while the description of the above embodiments is limited to discussing a droplet disposed on a nanostructured or microstructured surface, one skilled in the art will readily recognize that the above embodiments are intended to encompass any flow of a liquid across a surface or the movement of a surface through a liquid. Additionally, while pressure variations are discussed as being used to cause a liquid to penetrate a feature pattern, one skilled in the art will recognize that prior methods of causing such penetration, such as causing the surface tension of the droplet to drop, will be equally advantageous.
[0044] Also, in light of the principles set forth above, one skilled in the art will be able to devise many different applications could benefit from the ability to prevent penetration of a feature pattern or from reversing such a penetration. Finally, penetration of a liquid into a feature pattern and the reversing of that penetration may be accomplished by other means other than increasing or decreasing the temperature of the fluid within closed cells. For example, air may be blown/withdrawn into/from the cells, thus increasing/decreasing, respectively, the pressure within those cells. | A method and apparatus is disclosed wherein the flow resistance of a droplet disposed on a nanostructured or microstructured surface is controlled. A closed-cell feature is used in a way such that, when the pressure of at least a first fluid within one or more of the cells of said surface is decreased to or below a desired level, a droplet disposed on that surface is caused to at least partially penetrate the surface. In another illustrative embodiment, the pressure within one or more of the cells is increased to or above a desired level in a way such that the droplet of liquid is returned at least partially to its original, unpenetrated position. In yet another embodiment, a closed-cell structure feature pattern is used to prevent penetration of the nanostructured or microstructured surface, even when the pressure of the fluid disposed on the surface is relatively high. | 8 |
This is a continuation of application Ser. No. 360,698 filed May 15, 1973, now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to voltage monitors and more particularly to apparatus for monitoring the terminal voltage of a battery which supplies power for operating an electrically powered vehicle and for disabling a selected operative function of the vehicle when the battery reaches a predetermined discharge state.
SUMMARY OF THE INVENTION
In battery powered vehicles, for example a fork lift truck, it is desirable to insure that the operator will return the vehicle to the battery charging station so that the battery can be recharged when the battery reaches a predetermined discharge state. Selected operative functions of the vehicle should also be disabled until a fully charged battery is installed in the vehicle. Several difficulties are encountered in designing a monitor to assure that the vehicle is operated in this manner. For example, batteries in these applications are often subjected to short but rather heavy loads which cause the terminal voltage of the battery to momentarily drop quite significantly. Once the temporary load has been removed the battery terminal voltage will begin to recover to normal. However, the recovery rate will depend on the extent of the load, the charge condition of the battery and the duration of the load. There may also be switching transits which are generated as the controller is turned on and off. These characteristics mean that the charge condition of the battery cannot be determined by simply monitoring the terminal voltage of the battery.
The monitor should also be designed such that once the selected operative function of the vehcile has been disabled it cannot be reenabled until the battery terminal voltage exceeds a predetermined value. A particular vehicle may be capable of operating on a variety of battery voltages. This makes it desirable that the monitor be capable of monitoring a reasonable variety of battery voltage. Ideally the monitor should include an automatic scaling circuit so that no adjustment or circuit changes are required to the scale of the monitor.
The disclosed monitor includes a circuit which requires that the battery voltage exceeds a first threshold level before a selected operative function of the vehicle is enabled. After the selected operative function has been enabled the terminal voltage of the battery is continually compared to a second threshold and a first warning indicator is turned on if the battery terminal voltage falls below this level. At the same time that the first warning indicator is turned on, a first timing circuit is initiated to generate a signal which defines a first time interval. If the battery load recovers to a third threshold level before the time interval determined by the first timing circuit expires, the first warning is cancelled and normal operation is continued. However, if the battery voltage does not recover to the third threshold level during this period a second warning signal is turned on and a second timer circuit is initiated to generate a signal which defines a second time interval. If the battery voltage returns to a fourth threshold level during the second time interval the warning functions are cancelled and operation is returned to normal. However if the battery voltage does not return to the fourth threshold level during the second time interval, the selected operative function of the vehicle is disabled and normal operation can only be restored by installing a charged battery in the vehicle.
The terminal voltage of the battery is also continuously compared to a fifth threshold and the selected operative function of the vehicle disabled without substantial delay if the terminal voltage falls below this threshold.
The selected operative function may be re-enabled by two methods depending on how it was disabled. If it was disabled after the second warning signal persisted for a time interval specified by the second timer, the terminal voltage must rise above the fourth threshold before this operative function is re-enabled. If the disable occurred without warning because the terminal voltage decreased to or below the fifth threshold level, the terminal voltage must rise above the first threshold level before the operative function is re-enabled.
The various thresholds are independently adjustable. The first threshold is normally set to be substantially equal to the maximum terminal voltage of the battery. The fifth threshold is normally set below the expected operating range of the battery. Selecting these threshold levels in this manner means that during expected operating conditions the only time the operative function of the vehicle will be controlled by the first and fifth thresholds will be when the battery is disconnected from the monitor because it is being charged or for some other reasons. The other threshold levels and time intervals are selected to insure that the battery is not over discharged before the operative function is disabled.
The monitor also includes an automatic scaling circuit which selects the operating range of the monitor. Operation of this circuit is totally automatic and requires no manual adjustments or circuit modifications to change the scale of the monitor.
Although the invention is described with reference to a fork lift truck it should be obvious that the battery monitor can be utilized in other equipment which depends on electric storage batteries as a source of energy.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a functional block diagram of the monitor;
FIG. 2 is a schematic diagram of the automatic scaling circuit, the threshold circuits, the timing circuits, and the warning circuits;
FIG. 3 is a functional block diagram of the automatic scaling circuits;
FIG. 4 is a schematic diagram for the power supply utilized by the monitor.
DETAILED DESCRIPTION
FIG. 1 is a functional block diagram of the monitor. The voltage from the battery is coupled to an automatic scaling circuit 10. The output voltage of the automatic scaling circuit 10 is a predetermined fraction of the terminal voltage of the battery and is coupled to the first input terminals of first, second and third comparators, respectively illustrated at reference numerals 11, 12, and 13. The automatic scaling circuit 10 includes sensing and attenuating circuitry which automatically adjusts the range of the automatic scaling circuit such that the amplitude of the input signal to the comparators is appropriate for the actual terminal voltage of the battery being monitored. For example the monitor could be designed to have two ranges selected to monitor batteries having a maximum terminal voltage of either 36 or 48 volts.
When the monitor is connected to a battery the automatic scaling circuitry 10 adjusts an attenuator circuit to monitor a battery having a terminal voltage equal to the lowest voltage range of the monitor. The output voltage of the attenuator is sampled and if the voltage exceeds a predetermined threshold the attenuator is stepped to the next highest range. This step is repeated until the range of the monitor matches the battery voltage.
Conceptually the monitor may be designed to include any number of monitoring ranges. FIG. 3 illustrates in functional block diagram form a monitor for monitoring batteries having three different terminal voltages. FIG. 2 is a detailed schematic diagram of a circuit for monitoring batteries having two different terminal voltages. FIG. 2 illustrates the preferred embodiment of the invention.
The output signal of the automatic scaling circuit 10 is coupled to the first input terminal of the first, second, and third comparators, 11, 12 and 13. The second input to each of the comparators is provided by a precision voltage reference source 14. This reference source is a part of the power supply circuit which will be discussed in detail later. Each of the comparators normally includes an additional voltage divider circuit which scales the output voltage of the precision reference source 14 down to generate the different thresholds for the various comparators. The comparators are designed such that they have both high and low thresholds permitting each comparator to generate an output signal which indicates that the battery voltage has exceeded the high threshold or dropped below the low threshold level. The details of these comparator circuits will be discussed later.
The first comparator 11 generates two output signals. These signals are basically identical. Two signals are provided to isolate the circuits utilizing these signals from each other. Each of these signals has two levels, (high and low) with the high level being turned on when the battery voltage falls below the second threshold level and the low level being turned on when the battery voltage exceeds the third threshold level. One of the signals is coupled to the flashing warning circuit 15. Whenever the battery voltage falls below a second threshold the output signal of the first comparator 11 switches to its high state and initiates a circuit which generates a first warning signal which is coupled to the indicator 20. When this first warning signal is present a light 115 (FIG. 3) associated with the indicator 20 will alternately flash on and off.
The first warning signal is terminated when the first output signal of the comparator 11 switches to the low state indicating that the battery voltage has increased above the third threshold or whenever the continuous warning circuit 21 is initiated.
The second output signal from the first comparator 11 is coupled to a first timing circuit 22. This circuit is activated by the high level of the output signal of the first comparator 11. The first timing circuit generates a signal which specifies a time interval during which the battery voltage must rise above the third threshold level or the continuous warning circuit 21 will be activated. If the battery voltage does not exceed the third threshold value within this interval, the continuous warning signal is turned on and the flashing warning is turned off.
A second timing circuit 23 is initiated simultaneous with the initiation of the continuous warning. This timing circuit generates a signal which specifies a second time interval during which the terminal voltage of the battery must rise above the fourth threshold, determined by the second comparator 12, or the selected operative function of the vehicle will be disabled. If the second time interval expires and the voltage of the battery has not exceeded this threshold, the disabled circuit 24 will be initiated causing the selected operative function of the vehicle to be disabled. Alternatively, if the voltage of the battery does exceed this threshold within this time interval, the second comparator 12 will generate a signal which initiates the reset circuit 25. The reset circuit will then generate a signal which resets the first and second timing circuits, 22 and 23, to cancel the warning signals and restore normal operation.
After the selected operative function of the vehicle has been disabled because the warning signals have persisted for the specified time interval the battery voltage must rise above the fourth threshold level determined by the second comparator 12 before the disabled circuit 24 will permit the disabled feature to be reenabled. The thresholds are adjustable.
The third comparator 13 operates in conjunction with the disable circuit 24 to disable the selected operative function of the vehicle and the above moitoring functions until a charged battery has been installed in the vehicle. This is accomplished by continuously comparing the battery voltage to the first threshold and holding the selected operative function in a disabled state until this threshold is exceeded. The operative function is also disabled without substantial delay if the battery voltage falls below the fifth or low threshold of this circuit. The low threshold of this circuit is normally set below the lowest terminal voltage expected during normal operation. If the selected operative function is disabled by this circuit, the battery voltaage must rise above the first threshold before the operative function is reenabled.
FIG. 3 is a schematic diagram of the monitor except for the power supply. FIG. 4 is a schematic diagram of the power supply utilized by the monitor.
Many of the components of the schematic diagram (FIG. 3) are associated with more than one of the functions illustrated in FIG. 1. For this reason, this schematic diagram has not been rigorously divided into functional blocks corresponding to FIG. 1.
The circuit illustrated in FIG. 3 includes automatic scaling circuitry permitting the monitor to automatically change range. The circuit includes two monitoring ranges. For example, first range might be designed to monitor 36 volt batteries while the second range might be designed to monitor 36 volt batteries. Although only two ranges are illustrated in the detailed schematic of the monitor, the circuitry can be expanded to include three or more ranges. Circuitry illustrating in how this can be done will be discussed in detail later.
The positive and negative terminals, 30 and 31, of the monitor are coupled to the positive and negative terminals of the battery to be monitored and to a voltage divider network comprising a plurality of resistors and diodes. The diodes function as switches to change the impedance of the divider network which in turn changes the voltage output of the network. The output signal of this network is one input to comparator circuits.
More specifically, the positive terminal of the battery is coupled to input terminal 30 which is in turn coupled to the common junction of two range select resistors, 31 and 32. The second end of the first range select resistor, 31 is coupled to the positive terminal of first and second isolation and switching diodes, 34 and 35. The second terminal of the second range select resistor 32 is coupled to the positive terminal of third and fourth range selection and isolation diodes, 36 and 37. The negative terminal of the first and third isolation diodes, 34 and 36, are connected in parallel. The negative terminals of the second and fourth switching and isolation diodes, 35 and 37, are similarly connected. Two series connected resistors, 38 and 39, are connected between the negative terminals of the first and third isolation diodes 34 and 36 and the ground terminal of the circuit. A conventional diode and a Zener diode, 45 and 46, are connected in series. The series combination of these diodes is connected in parallel with the resistor network comprising two series coupled resistors, 38 and 39. The junction formed by connecting the isolation diode 45 to the Zener diode 46 forms the output terminal of the automatic scaling network. This terminal is coupled to the negative input terminal of the first, second and third comparators 11, 12 and 13.
The polarity protection diode 45 protects the comparators from reverse plurality voltages while the Zener diode 46 protects the comparators from voltages exceeding the maximum input voltage rating of the comparators. The range selection and isolation diodes 34 through 37 permit the range selection resistors 31 and 32 to be switched in and out to change the operating range of the monitor.
In the illustrated circuit the range is switched from the low range to the high range by signals generated by the automatic range comparator 47. This switching function accomplished by coupling the positive terminals of isolation diodes 36 and 37 to ground through a low impedance when the output voltage of the automatic range selection circuit exceeds a value which would normally be expected to be encountered when the circuit is coupled to a battery having a terminal voltage within the low range of the monitor. The only time this will occur is when a battery having a terminal voltage above the low range is coupled to the monitor.
The circuits illustrated in FIG. 3 derive their normal operating voltages from the power supply illustrated in FIG. 4. A positive output voltage from the power supply illustrated in FIG. 4 is coupled to power supply sensor terminal 48. The voltage appearing at this terminal is coupled to the base of the first transistor 49 through the series combination of a resistor and Zener diode 50 and 51.
This voltage is also coupled to the input of a second transistor 55 through the series combination of a resistor and a diode 56 and 57. The breakdown voltage of the Zener diode 51 is selected such that when the monitor circuit is connected to a battery that the second transistor 55 will come on prior to the first transistor 49. This assures that the second transistor 55 will discharge a filter capacitor 58 through a discharge resistor 59 before the first transistor 49 begins conducting. When the Zener diode 51 breaks down the first transistor 49 will begin conducting causing the voltage at the collector of this transistor to be reduced to a point which causes the second transistor 55 to be cut off. The collector of the first transistor is also coupled by a coupling diode 59 to the input of a third transistor 60. This transistor discharges a filter capacitor 61 through a resistor 62 in a manner similar to that previously described with respect to filter capacitor 58.
Filter capacitor 58 assures that high frequency transits appearing at the input terminals of the automatic range comparator 47 will be filtered to a degree sufficient to assure that this comparator is not upset by transients. Filter capacitor 61 performs a similar function with respect to the output voltage of the automatic range circuit. It is necessary to discharge these capacitors, as described above, whenever the battery is removed from the vehicle in order to assure that the various comparator circuits begin operation in a known condition.
As discussed above filter capacitor 58 is discharged through resistor 59 and transistor 55. This capacitor is connected from the negative input terminal of the comparator amplifier to the ground terminal of the circuit. The filter capacitor is selected such that the voltage appearing at the negative terminal of the comparator amplifier rises at a slower rate than the voltage coupled to the positive terminal of this amplifier. This assures that at the beginning of the cycle the output voltage of the comparator amplifier will be high or positive. This causes the automatic scaling circuitry to begin operation in the low range. This positive voltage is coupled to the base of an amplifier transistor 69 by a network consisting of two series couple resistors 66 and 67 and a diode 68. This positive voltage causes this amplifier transistor 69 to conduct. The voltage drop across the collector resistor 70 causes the collector terminal voltage of transistor 69 to drop to a value of which causes a switching transistor 71 to cut off. The collector terminal of the switching transistor 71 is coupled to the positive terminal of the two low range isolation diodes 36 and 37. However, since the switching transistor 71 is non-conducting it has essentially no effect on the ranging circuit causing the ranging resistors 31 and 32 to be effectively connected in parallel. This reduces the ranging network to two series connected resistors with the first resistor being the parallel combination of the range resistors 31 and 32 and the second resistor being the series combination of two resistors 38 and 39.
The low voltage end of the range resistors 31 and 32 are respectively coupled by isolation diodes 35 and 36 to the negative inputs of the automatic ranging comparison circuit 47. When this voltage rises above the voltage coupled to the positive input terminal of the ranging comparator 47 the output signal of this comparator changes from positive to negative. This negative signal causes the switching transistor 71 to be turned on. When the switching transistor 71 becomes highly conductive the positive terminals of isolation diodes 36 and 37 are coupled to ground through the low impedance of the switching transistor 71. This causes the third isolation diode 36 to be reverse bias and in effect removes the second ranging transistor 32 from the input circuit. This causes a larger proportion of the battery voltage coupled to terminal 30 to appear across the first ranging transistor 31 thereby increasing the range of the monitoring circuit.
The positive going voltage at the collector of transistor 69 is also coupled to the base of transistor 60 by a coupling capacitor 77. This positive going pulse turns on transistor 60 to discharge filter capacitor 61. This causes the three other comparators, 11, 12 and 13 to switch back to their beginning state. This is important because a partially discharged high voltage battery may have a voltage which is sufficient to cause comparator 13 to generate a signal which enables the selected operative function while the monitor was on the low but improper scale but which is insufficient to enable this function when the monitor is on the proper scale.
The four comparators 11, 12, 13 and 47 used in the circuit illustrated in FIG. 3 are essentially identical. Therefore the first comparator 11 will be discussed in detail. The operation of the other comparators should be obvious in view of the discussion of the first comparator. Similar components in the various comparators are labeled with the same reference numerals. It is believed that this will aid in understanding the similarities between the comparators.
The first comparator is illustrated in reference numeral 11 in FIG. 3. The basic comparator comprises a differential amplifier 72 a feedback network, a divider network coupled to the one input of the differential amplifier 72, and a filter capacitor 73. The feedback network comprises a fixed resistor 74 in series with the variable resistor 75 and a diode 76. The divider network comprises two resistors 80 and 81. The resistor divider network is coupled between a reference voltage input terminal 82 and the ground terminal of the comparator. The junction formed by series connecting these resistors is coupled to the positive input terminal of the differential amplifier 72 and the feedback network is coupled between the output and the positive input terminal of the amplifier 72. The gain of the amplifier 72 is high and the feedback is positive. This causes the comparator to function as a memory. The output signal of the comparator is a two-level signal with the signal changing from one level to the other depending on the relative amplitude of the voltages appearing at the input terminals of the comparator. The positive and negative threshold voltages of the comparator 11 are independently adjustable. For example, the positive threshold is basically determined by the value of the resistors comprising the feedback network, 74 and 75. The negative threshold is basically determined by the resistor divider network. Thus the positive threshold can be adjusted without substantially effecting the negative theshold by varying the variable resistor 75. This separation of the threshold adjustments is possible because when the output signal of the amplifier 72 is negative the diode 76 and the feedback network is reversed bias. This reduces the feedback to zero making the negative threshold a function of the input divider comprising resistors 80 and 81. By suitably selecting the components of the feedback and divider network the negative and positive thresholds of this comparator can be independently adjusted over a wide range.
It is desirable to have two outputs from the first comparator 11 with the output signals having a reasonable degree of isolation between each other. This is accomplished by connecting two series resistor divider networks across the output of the amplifier 72 and using the output of these dividers as the output signals of the first comparator 11. The resistors comprising these networks are shown at reference numerals 86 through 89. The second comparator 12 is essentially identical with the first comparator 11 except that only one output signal is desired and therefore only one resistor divider network is coupled across the output of the amplifier. The third comparator 13 is also similar to the first comparator 11 except that the diode and feedback network has been eliminated since it is only the high threshold level that must be accurately set. The comparator 47 utilized by the automatic scaling circuit is also similar to the first, second and third comparators. Because of these similarities it is believed to be unnecessary to discuss the detailed operation of the other comparators.
The first output signal of the first comparator 11 is coupled to the input of a circuit which drives the flashing warning indicator. This circuit includes transistors 94 through 98, a feedback diode 99, and a unijunction transistor 100.
The first threshold level of the first comparator 11 is normally adjusted such that when the battery voltage is within the normal operating range the output signal of the first comparator 11 is low. This output signal is coupled to the input transistor 94 of the flashing warning circuit through a coupling diode 101. The low value of this signal causes the input transistor 94 to be turned off. Turning off this transistor causes the second transistor 95 to be biased into the highly conductive region by base current which flows through the collector resistor 102 of the input transistor 94. This highly conductive transistor forms a short circuit across a timing capacitor 105. This is the timing capacitor for the circuit which generates the on and off signals to operate the flashing warning indicator. Holding this capacitor 105 in a discharged state disables the flashing circuit holding the flashing warning in the off condition.
When the battery voltage falls below the second threshold the output signal of the first comparator 11 goes high turning the input transistor 94 on and the second transistor 95 off. When the second transistor 95 is turned off the timing capacitor 105 begins to charge through the collector resistor 106 of the second transistor 95. The unijunction transistor 100 triggers when the timing capacitor 105 accumulates sufficient charge to cause the voltage drop across this capacitor to rise to the trigger point of the unijunction transistor 100. The trigger level of the unijunction transistor 100 is determined by a resistor bias network comprising two resistors 107 and 108. When the unijunction transistor 100 triggers a second capacitor 109 is charged through a resistor 110. The voltage across capacitor 109 is coupled to the base of transistor 96 by a resistor 111. When this capacitor has accumulated sufficient charge the third transistor 96 will begin conducting and turn on to parallel connected output transistors 97 and 98. When the two output transistors turn on the first timing capacitor 105 will be discharged rather rapidly through a feedback diode 99. This causes the unijunction transistor 100 to turn off. However the output transistors 97 and 98 will not be turned off immediately because sufficient charge has accumulated on the second capacitor 109 to hold these transistors on for a brief period of time. This causes the circuit to oscillate alternately turning on and off a flashing light 115 to generate the previously described flashing warning signal. This warning will continue until it is either terminated by the battery voltage coupled to the first comparator rising above the third threshold or by the beginning of the steady warning signal to be subsequently described.
An audible warning device 114 is also connected in parallel with the light 115. A switch 113 permits these warning devices to be tested in the absence of a warning signal.
The second output signal from the first comparator 11 is coupled to the input of the first timing circuit, 22. This timing circuit is triggered substantially coincident in time with the beginning of the flashing warning signal. At the end of the time interval determined by this circuit, the flashing warning will be terminated and the steady warning signal will be initiated provided the battery voltage has not increased above the third threshold level.
The first timing circuit 22 includes two transistors an operational amplifier, a unijunction transistor, and associated resistors and capacitors. The transistors are illustrated at reference numerals 116 and 117. The operational amplifier and the unijunction are respectively illustrated at reference numerals 118 and 119.
When the terminal voltage of the battery being monitored exceeds the third threshold level the output signal from the first comparator 11 switches to its low state causing the input transistor 116 of the first timing circuit 22 to be biased off. This causes the timing capacitor 120 to charge through the collector resistor 125 and the isolation diode 126. The timing capacitor 120 will be charged to a voltage which is sufficient to bias the unijunction transistor 118 to the off condition. This disables the first timing circuit 22.
When the battery voltage falls below the second threshold the output signal of the first comparator 11 switches to its high state turning on the input transistor 116. This causes the collector terminal of this transistor to go low thereby reducing the charging current which normally flows through the collector resistor 125 of the first transistor to essentially zero. Discharge of the timing capacitor 120 by the input transistor 116 is prevented by the isolation diode 126 which becomes reverse bias when the input transistor 116 is turned on. After the isolation diode 126 becomes reverse bias the timing capacitor 120 begins to discharge through two series connected resistors, 127 and 128. When the voltage across the timing capacitor 120 falls below the trigger point of the unijunction transistor 118, this unijunction triggers causing the output of amplifier 119 to go low. The low output voltage of this amplifier turns on the output transistor 117. The collector of the output transistor 117 is coupled to the positive input terminal of the amplifier 119 by a series diode resistor network comprising a resistor 129 and a diode 130. This feedback is positive causing the output signal of the amplifier 119 to remain high and retains the output transistor 117 and the highly conductive state.
The collector terminal of the output transistor 117 is also coupled to the base terminal of the two parallel connected transistors, 97 and 98, through a resistor 131. When the output transistor 117 becomes highly conductive a steady signal is applied to the base terminals of these transistors, 97 and 98, causing the warning light 115 to operate continuously thereby generating the continuous warning signal. The continuous warning signal will remain on until the battery voltage rises above the fourth threshold determined by comparator 12.
This is accomplished by feeding back the output signal from transistor 117 via resistor 129 and diode 130 into comparator 119 to latch up this comparator. This effectively inhibits the reset action of the (first) comparator 72 which would result when the voltage rose above the third threshold level. The circuit is reset only when the voltage rises above the fourth threshold. Once reset, the circuit would then respond, as previously described, to the second and third voltage levels provided the first time delay limit has not been exceeded.
The output signal of the first timing circuit 22 is also coupled to the inputs of a second timing circuit 23 such that the second timing circuit 23 is initiated when the steady warning indicator is turned on. This second timing circuit comprises an input transistor 135 and an output transistor 136, a unijunction transistor 137 and a differential amplifier 138. When the steady warning indicator is turned on, as previously described above, the collector of transistor 117 goes positive. This positive voltage is coupled to the base of the input transistor 135 of the second timing circuit through an input resistor 139. This causes the input transistor 135 to become highly conductive causing the collector terminal of this transistor to be approximately zero volts with respect to ground. This reverse biases and isolation diode 140 permits the timing capacitor 145 to begin discharging through the timing resistor 146. When the voltage across the timing capacitor 145 falls below the trigger point of the unijunction transistor 137, the unijunction triggers thereby providing a signal to the positive input of amplifier 138. This signal causes the output signal of this amplifier to go high.
The high output signal of differential amplifier 138 is coupled to the base of transistor 136 by a network comprising resistors 131 and 132 and diode 133 thereby causing the output transistor 136 to become highly conductive. Positive feedback to the positive input terminal of amplifier 138 from the collector of the output transistor 136 is provided by the feedback resistors 147 and 148. This feedback causes the amplifier 138 and the output transistor 136 to function as a memory circuit. A reset signal is also coupled from the reset circuit to this circuit by an isolation diode 149.
When the output transistor 136 of the second timing circuit 23 becomes highly conductive, indicating that the timing interval specified by this circuit has expired, an SCR drive transistor 150 coupled to the collector of this transistor through a coupling diode 155 becomes highly conductive depriving the SCR 156 of its gate drive current because of the increased voltage drop across the collector resistor 157. This turns off the SCR 156 and disables the selected operable function of the vehicle. Operation can only be restored when the battery voltage rises above the fourth threshold level.
The above disabled sequence may be interrupted by a reset signal which resets both the warning and timing circuits if the battery voltage rises above the fourth threshold level before the expiration of the time interval specified by the second timing circuit 23. The output signal of the second comparator 12 initiates a reset circuit 25 to generate this signal.
The output signal of the second comparator 12 is coupled to the reset circuit 25 comprising two transistors, 157 and 158. The lower threshold level of the second comparator 12 is set to be practically the same as the lower threshold level of the first comparator 11. Therefore when the first timing circuit is initiated the output signal of the second comparator will go high causing the input transistor 157 of the reset circuit to become highly conductive. The collector voltage of this transistor 157 drops to a low value due to the current through its collector resistor 159. If the battery voltage rises above the fourth threshold, indicating that the timing and warning circuits should be reset to prevent a disable signal from being generated, the output signal of the second comparator 12 will go negative causing the input transistor 157 to turn off. Turning off this transistor causes a positive signal to be coupled to the base of the second transistor 158 of this circuit through coupling capacitor 160 and bias resistor 161. This causes the output transistor 158 to become highly conductive generating a negative going reset signal which is coupled to the input of amplifier 119 of the first timing circuit 22 and amplifier 138 of the second timing circuit 23 causing these circuits to be reset thereby restoring normal operation.
FIG. 3 is a diagram illustrating how the automatic scaling circuit can be extended to three ranges. The circuit includes three range resistors, 190, 191, and 192. The circuit switches to the lowest range when the plus input terminal is connected to the battery to be monitored is connected to the circuit. In the low range, all the switching and isolation diodes, 193 through 198, are forward biased. The input impedance of the change scale circuit, 199, and the switches, 201 and 202, is high causing these elements to draw very little current. Under these conditions, the range resistors 190, 191 and 192 are effectively connected in parallel. This forms a voltage divider network comprising the parallel combination of the range resistor, 190, 191 and 192, and the series combination of resistors 203 and 204.
In the low range, all the diodes 194, 196 and 198, which couple the low voltage end of the range resistors to the change scale circuit 199 will be forward biased. This causes the voltage coupled to the change scale circuit 199 to be equal to the output signal except for the voltage drop across a forward biased diode.
The voltage coupled to the change scale circuit 199 is compared to a reference voltage. If this voltage exceeds the reference, the battery voltage is too high for the low scale and the change scale circuit increments a counter 200 one count. This turns a switch SW1 causing it to switch to a low impedance state. This effectively grounds the low voltage end of third ranging resistor 192 and reverse biases the associated isolation diodes 197 and 198. Reverse biasing these diodes effectively removes the third ranging resistor 192 from the circuit and reduces the amplitude of the output signal. The input voltage to the change scale circuit is again compared to the reference and if exceeds the reference, the counter 200 is again incremented turning on switch SW2. This in effect removes the second ranging resistor 191 from the circuit and again increases the range of the circuit. This procedure is repeated until the range of the monitor corresponds to the battery voltage. This circuit can be expanded to include any desired number of ranges.
In general, each of the ranges will correspond to the maximum terminal voltage of a battery to be monitored. In the illustrated example the ranges might correspond to battery voltages of 24, 36 and 48 volts.
The monitor and alarm circuits discussed above are supplied with DC operating voltages from a power supply illustrated in FIG. 4. The illustrated power supply utilizes an integrated circuit switching mode regulator module 164. This module may be a commercially available model No. 723 manufactured by Texas Instruments. The output of the switching regulating module 164 is coupled to an amplifier transistor 165. The collector of this transistor is coupled to a regulator transistor 166 by a resistor 167 and a diode 168. The base to collector junction of this transistor 166 is by-passed by the series combination of a resistor 169 and a Zener diode 170. This by-pass of the base to collector junction of this transistor prevents it from being damaged by high voltage switching transients which may be present on the battery terminal voltage.
The emitter of the regulator transistor 166 is coupled to an inductor 169. The inductor 169 in conjunction with the filter capacitors 170 and 171 removes substantially all of the AC components of the output current from the regulator transistor 166. The collector supply voltage for the circuits illustrated in FIG. 3 is available at terminal 175. The precision supply voltage for the comparators and the delay circuits is obtained by dividing down the collector supply voltage by a series circuit comprising a resistor and Zener diodes 176 and 177.
The output voltage of the power supply is determined by an adjustable resistor 176. Bias voltages are supplied to the regulator module by a network comprising resistors 177 through 180 and a Zener diode 181 limits the bias voltage to a safe value. Another Zener diode 182 is coupled between the collector and emitter terminals of the amplifier transistor 165 to assure that high voltage transit which may be superimposed on the battery voltage will not exceed the base to emitter rate in this transistor. Transits on the battery voltage are further reduced by a filter network comprising a resistor 183 and filter capacitors 184 through 186. A filter capacitor 187 reduces transients superimposed on the regulator module 164 bias voltages. | A monitor for disabling a selected operative function of the battery powered vehicle when the battery reaches a predetermined discharge state is disclosed. The discharge state of the battery is determined by continuously monitoring the terminal voltage of the battery. Automatic scaling circuitry is included so that the monitor automatically adjusts to the range which is appropriate for the battery being monitored. Two warning signals are generated with each warning signal indicating a progressively lower discharge state of the battery. After the second warning signal has been on for a predetermined time period, a selected operative function of the vehicle is disabled. If the vehicle is a fork-lift truck for example, the lift mechanism might be disabled however the main drive motor could remain operative so that the truck could be returned to the battery charging station. The monitor also prohibits the disabled function from being reenergized except when a fully charged battery is installed in the vehicle. | 8 |
TECHNICAL FIELD
[0001] This invention relates to a method and an apparatus for torque ripple reduction in electric motors.
BACKGROUND OF THE INVENTION
[0002] Most motor vehicle steering systems produced today employ some type of power assist steering system to assist the driver in steering the front wheels. In general, power assist steering systems employ a hydraulic pump to provide pressurized fluid to a piston connected to or formed in the steering rack assembly, the pressure being regulated by a valve which is opened or closed by an amount that varies with the torque in the steering column. Thus, as the driver exerts more effort against the steering wheel, the valve is opened to provide more fluid to the piston, thereby assisting the driver in steering the vehicle.
[0003] It has been heretofore known to provide a power assist system using an electric motor as the source of motive force as opposed to pressurized hydraulic fluid. This would improve fuel economy and reduce the manufacturing cost of the vehicle. Furthermore, it is suggested that reliability of the system would be improved since many components including the hydraulic pump and fluid lines can be eliminated. However, prior attempts at making an electric power assist steering system have proved unsatisfactory.
[0004] Perhaps the most vexing issue with electric power assist steering systems has been torque ripple felt at the hand wheel. Torque ripple is the variation in reaction torque felt by the driver as the hand wheel is turned. Because drivers are so used to the smooth response of the hydraulic power assist steering systems, they have generally reacted unfavorably to electric power assist steering systems due to the presence of torque ripple.
[0005] Most torque ripple is caused by the electric motor that provides the power assist motive force. There are two primary sources of torque ripple in the electric motor. The first is known as cogging torque, which is caused by the magnetic attraction between the rotor mounted permanent magnets to the stator. It has been known to skew the rotor magnets and to use more expensive surface-parallel type magnets to reduce the effect of cogging torque, however, the magnetization process and machining process for skewed and for surface parallel magnets is higher, thereby reducing the benefits of the electric power assist steering system. The other primary source of torque ripple is the harmonics content in the line-to-line back-emf due to an imperfect sinusoidal back-emf waveform.
BRIEF SUMMARY OF THE INVENTION
[0006] The above discussed and other drawbacks and deficiencies are overcome or alleviated by a method of selecting a magnet angle for a permanent magnet electric motor including determining a first magnet angle where cogging torque is minimized, determining a second magnet angle where harmonic content of n th harmonic is minimized, and using the first magnet angle and the second magnet angle, determining an optimal magnet angle for minimizing both cogging torque and n th harmonic.
[0007] In another embodiment, a method of reducing torque ripple in an electric motor includes providing a first magnet ring on a rotor positioned about a shaft of a motor, the first magnet ring having magnets each occupying a magnet angle ε on the rotor, providing a second magnet ring on the rotor, the second magnet ring having magnets each occupying a magnet angle ε on the rotor, and shifting the second magnet ring a non-zero number of degrees relative to the first magnet ring wherein ends of each magnet within the second magnet ring are located at different angular positions than ends of each magnet within the first magnet ring relative to a shaft axis of the shaft.
[0008] In another embodiment, a motor for reducing torque ripple includes a shaft having a shaft axis, a rotor positioned about the shaft, a first magnet ring positioned on the rotor, the first magnet ring comprising magnets each occupying a magnet angle ε on the rotor, and a second magnet ring positioned on the rotor, the second magnet ring comprising magnets each occupying a magnet angle ε on the rotor, wherein the second magnet ring is shifted a non-zero number of degrees relative to the first magnet ring wherein ends of each magnet within the second magnet ring are located at different angular positions than ends of each magnet within the first magnet ring relative to the shaft axis of the shaft.
[0009] In another embodiment, a motor for reducing torque ripple includes a shaft having a shaft axis, a rotor positioned about the shaft, and a plurality of magnets positioned about the rotor, each magnet occupying a magnet angle ε on the rotor, wherein the magnet angle ε is an optimal magnet angle for minimizing cogging torque and line to line back emf harmonics.
[0010] The above discussed and other features and advantages of the present invention will be appreciated and understood by those skilled in the art from the following detailed description and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The present invention will now be described, by way of example, with reference to the accompanying drawings, in which:
[0012] [0012]FIG. 1 shows a portion of a cross-section of a permanent magnet electric motor having surface parallel magnets;
[0013] [0013]FIG. 2 shows a portion of a cross-section of a permanent magnet electric motor having breadloaf magnets;
[0014] [0014]FIG. 3 shows an exemplary plot of cogging torque;
[0015] [0015]FIG. 4 shows an exemplary chart showing harmonic content of back-emf;
[0016] [0016]FIG. 5 shows a plot of cogging torque and back-emf harmonics varying with respect to the magnet angle for the motor of FIG. 1;
[0017] [0017]FIG. 6 shows a plot of cogging torque and back-emf harmonics varying with respect to the magnet angle for the motor of FIG. 2;
[0018] [0018]FIG. 7 shows a side view of the magnets of FIG. 1 split in two pieces;
[0019] [0019]FIG. 8 shows a side view of skewed magnets; and,
[0020] [0020]FIG. 9 shows an exemplary electric power assist steering system using the motor of FIG. 1 or 2 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0021] The problem of torque ripple caused by the harmonics content in the line-to-line back-emf due to an imperfect sinusoidal back-emf waveform is identified and discussed in more detail in the commonly-assigned U.S. Pat. No. 6,380,658 issued on Apr. 30, 2002 and incorporated herein by reference in its entirety.
[0022] In one embodiment of eliminating the cogging torque source of torque ripple without using the expensive process of skewing, the below described embodiment uses a low-cost magnet structure, such as bread-loaf type magnets. Elimination of skewing and use of bread-loaf type magnets reduces the magnet manufacturing cost, which in turn lowers the motor manufacturing cost. Thus, this embodiment provides a cost-effective, high-performance actuator for electric power steering applications.
[0023] A brushless permanent magnet electric motor 10 having surface parallel magnets 18 is shown in FIG. 1. Motor 10 includes a stator 12 having disposed therein a rotor 14 mounted to shaft 15 . Stator 12 includes a plurality of slots 16 having windings formed therein for generating a magnetic field which interacts with the magnetic fields produced by surface parallel magnets 18 . In the exemplary embodiment, stator 12 has twenty-seven slots 16 and rotor 14 has six magnets 18 ; thus, the slot/pole ratio is 4.5. Magnets 18 may be separated by air spaces 26 equidistantly spaced between the magnets 18 . Windings disposed in slots 16 may be provided in a traditional manner as generally known, or fractional pitch windings may be used in conjunction with this invention. For example, the fractional-pitch winding scheme described in commonly-assigned U.S. patent application Ser. No. 09/850,758, which was filed on May 8, 2001 by Buyun Liu et al. and published on Nov. 14, 2002 as Publication No. US2002/0167242 A1, and which is hereby incorporated herein by reference in its entirety, or one similar thereto may be employed.
[0024] In another embodiment, a permanent magnet electric motor 11 has breadloaf magnets 20 as shown in FIG. 2, but is otherwise similar to the motor shown in FIG. 1. Each surface-parallel magnet 18 and breadloaf magnet 20 includes an outer face, 19 and 21 respectively, thereof which delimits an angle ε at the axis of shaft 16 . Angle ε will be referred herein as the magnet angle where the angle ε corresponds to the amount of surface area of the rotor 14 that comprises a magnet. In other words, angle ε is the width of a magnet in electric angle in relation to a motor shape.
[0025] As the rotor rotates within motor 10 , magnets 18 , 20 interact with stator 12 due to the mutual attraction and generate what are commonly referred to as cogging torques. FIG. 3 shows a plot of cogging torque with respect to the rotor position in mechanical degrees (mDeg.) for the motor of FIG. 2 with magnets 20 not having any skew. This plot was generated using finite element analysis. Assuming that positive cogging torque is applied in a clockwise direction and the angles are measured counter-clockwise, or vice versa, it can be seen, as the rotor is rotated from 0 mDeg. to 3⅓ mDeg., the cogging torque is directed against the direction of rotation. As rotor continues from 3⅓ mDeg. to 6⅔ mDeg., the cogging torque is directed in the direction of rotation. Thus, an equilibrium is reached every 6⅔ degrees. In other words, the cogging frequency is 54 cycles per mechanical revolution (CPMR), which in this case happens to be twice the number of slots in stator 12 (twenty-seven).
[0026] [0026]FIG. 4 shows a graph describing the amplitude of the harmonics as a percentage of the fundamental frequency component present in the line-to-line back-emf. The fundamental frequency ƒ for a sinusoidal motor is given by ƒ=NP/120 Hz, where N is the motor speed in rpm and P is the number of rotor poles. Reference is again made to the commonly-assigned U.S. Pat. No. 6,380,658 issued on Apr. 30, 2002, which is incorporated herein by reference, for detailed explanation as to the development of this data. Essentially, it is the result of Fourier analysis on the line-to-line back-emf. In this example, the 5 th harmonic content is about 0.4% of the fundamental component. This may not be acceptable for applications such as electric power steering. As previously described, skewing may help lower the harmonic content in the line to line back-emf, but is a costly alternative.
[0027] The amplitude of the cogging torque (FIG. 3) is about 19 mN−m, peak-to-peak (along the vertical axis of the graph). If magnets 20 were skewed in the known manner, cogging torque could be significantly reduced, but skewed magnets have complex geometries and are expensive to manufacture. However, extensive finite element analysis shows that the main sources of torque ripple, including cogging torque and harmonics in the line-to-line back-emf, can be controlled by varying the magnet angular width (the angle that the outer surface of the magnet produces at the center).
[0028] [0028]FIGS. 5 and 6 show the dependency of the peak-to-peak cogging torque and harmonic contents on the magnet angle for surface parallel and breadloaf type rotor magnets, respectively. As clearly represented in the plots, the peak-to-peak cogging torque reduces to zero at about 42 mDeg. and 48.5 mDeg. for the surface parallel magnet and at about 49 and 55.5 mDeg. for breadloaf magnets. From these figures, it can be seen that proper design of the magnet angle may reduce the cogging torque.
[0029] Once the magnet angles correlating to the minimum values of cogging torque are known, it is possible to select magnet angles to minimize the back-emf harmonics as well. For example, as shown by the afore-mentioned commonly-assigned U.S. Pat. No. 6,380,658, the fifth harmonic component of line-line back emf can be reduced to zero where sin (εn/2)=0°, 180°, 360°, 540°, etc., in electrical angle, where n=the harmonic component being reduced to zero. Thus, ε=2(360°)/5=144 eDeg., which correlates to 48° in the 6-pole electric motor of the example shown in FIG. 2 (144°/number of pole pairs). Thus, the fifth harmonic can be reduced to zero with a magnet angle of 48 mDeg., which is very close to a magnet angle of 48.5° where cogging torque is minimized, as shown in FIG. 5. Thus, in order to cancel the 5 th harmonic, the theoretical value of ε=48°. FIG. 5 shows one minimum of cogging torque close to the magnet angle, which is good for minimum 5 th harmonics also.
[0030] Since the 5 th and 7 th harmonics are the most undesirable terms, the minimization of the 5 th and 7 th harmonic terms will make resultant waveform closer to sine wave. By plotting the 5 th and 7 th harmonics contents around the magnet angle corresponding to a minimum cogging torque, an optimum magnet angle minimizing the effects of both cogging torque and harmonics can be determined. It should be noted that meeting the magnet angle for minimizing cogging torque is much more difficult than meeting an angle which minimizes the harmonics. That is, as is clear from a review of FIGS. 5 and 6, any deviation, plus or minus, from the magnet angle which minimizes cogging torque results in sharp increases in cogging torque. Thus, when selecting an optimum magnet angle, choosing a magnet angle as close as possible to the magnet angle which minimizes cogging torque is important. To take the 5 th and 7 th harmonics into consideration, the optimum magnet angle for minimizing the cogging torque could be weighted more significantly than the optimum magnet angles which minimize the 5 th and 7 th harmonics. For example, if an optimal magnet angle is to be derived to satisfy the minimization of cogging torque and 5 th harmonics, then the cogging torque could be weighted 0.95 and the 5 th harmonics could be weighted 0.05, where the weighting factors add up to one. By example only, if the magnet angle for minimizing cogging torque is 48.6 and the magnet angle for minimizing the 5 th harmonics is 48.5, then using exemplary weighting factors, the optimal magnet angle would be 48.595.
Optimal magnet angle=(weighting factor 1 )angle 1 +(weighting factor 2 )angle 2
[0031] Where weighting factor 1 +weighting factor 2 =1
[0032] Similarly, if the 7 th harmonic minimization is to be taken into consideration,
Optimal magnet angle=(weighting factor 1 )angle 1 +(weighting factor 2 )angle 2 +(weighting factor 3 )angle 3
[0033] Where weighting factor 1 +weighting factor 2 +weighting factor 3
[0034] For both the surface-parallel and bread loaf type magnets shown in FIGS. 1 and 2, the optimum magnet angle was found to be about 48.5°. The plots in FIGS. 5 and 6 show how accurate the magnet angle should be in order to minimize the peak-to-peak cogging torque. In the previous analysis, the number of cogging cycles per mechanical revolution (CPMR) came out to be 54 assuming the magnets are identical and located ideally. Research shows that the manufacturing variations have significant influence on the amplitude and frequency of the cogging torque.
[0035] Slight variation in the magnet geometry or dislocation of the magnets results in higher amplitude and lower CPMR of the cogging torque. If the error is sufficiently great, the CPMR of the cogging torque may be equal to the number of slots, i.e., for the exemplary 27 slot motor shown in FIG. 1 and 2 , the cogging torque will be 27 cycles per mechanical revolution (CPMR).
[0036] Under these circumstances, the cogging torque cannot be minimized by setting the magnet angle as described above, which only minimizes the 54 CPMR component of cogging torque. To eliminate the 27 CPMR component of cogging torque which occurs due to manufacturing variations, the magnets 18 , 20 are segmented into two pieces 22 , 24 as shown in FIG. 7. Each piece 22 , 24 is half the stack length long, that is, each piece 22 , 24 has the same axial length. The piece 22 , 24 are relatively shifted by 6⅔ degrees in space. The rotor 14 can thus be viewed as having two sets of magnets 18 , 20 where each set consists of six poles and one set is 6⅔ mechanical degrees shifted in space from the other set. The axial length of the combined pieces 22 , 24 should be equivalent to an axial length of a rotor which is not divided into two pieces, as shown in FIG. 8. The 27 CPMR component of cogging torque should cancel out.
[0037] The motor designed according to the above-mentioned method is useful where smooth power without any discernable torque ripple is desired.
[0038] One such application is in an electrical power steering system. Referring now to FIG. 9, reference numeral 40 generally designates a motor vehicle power steering system employing motor 10 . The steering mechanism 42 is a rack-and-pinion type system and includes a toothed rack (not shown) and a pinion gear (also not shown) located under gear housing 44 . As the hand wheel 46 is turned, the upper steering shaft 48 , connected to the lower steering shaft 50 through universal joint 52 , turns the pinion gear. Rotation of the pinion gear moves the toothed rack, which moves tie rods 54 (only one shown), that in turn move the steering knuckles 56 (only one shown), which turn wheels 58 (only one shown).
[0039] Electric power steering assist is provided through the unit generally designated by reference numeral 60 and includes a controller 62 and the electric motor 10 . The controller 62 is powered by a vehicle power supply 66 through line 68 . The controller 62 receives a signal representative of the vehicle velocity on line 70 . Steering pinion gear angle is measured through position sensor 72 , which may be an optical encoding type sensor, variable resistance type sensor or any other suitable type of position sensor, and fed to the controller 62 through line 74 .
[0040] As the steering wheel 46 is turned, torque sensor 73 senses the torque applied to the hand wheel 46 by the vehicle operator. The torque sensor 73 may include a torsion bar (not shown) and a variable resistive-type sensor (also not shown) which outputs a variable resistance signal to controller 62 through line 76 in relation to the amount of twist on the torsion bar. Although this is the preferable torque sensor, any other suitable torque-sensing device used with known signal processing techniques are contemplated.
[0041] In response to the inputs on lines 70 , 74 , and 76 , the controller 62 sends a current command or a voltage command through line 78 to the electric motor 10 . The motor 10 in turn supplies torque assist to the steering system through a worm 80 and a worm gear 82 , in such a way as to providing a torque assist to the vehicle steering in addition to a driving force exerted by the vehicle operator.
[0042] Note that any torque ripple generated by motor 10 would be felt at hand wheel 46 . In this environment, motor 10 designed and manufactured according to the above method, will preferably generate torque ripple below perceptible levels.
[0043] While the invention has been described with reference to an exemplary embodiment, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims. Terms used herein such as first, second, etc. are not intended to imply an order in space or importance, but are merely intended to distinguish between two like elements. | A motor for reducing torque ripple includes a shaft having a shaft axis, a rotor positioned about the shaft, a first magnet ring positioned on the rotor, the first magnet ring having magnets each occupying a magnet angle ε on the rotor, and a second magnet ring positioned on the rotor, the second magnet ring having magnets each occupying a magnet angle ε on the rotor, wherein the second magnet ring is shifted a non-zero number of degrees relative to the first magnet ring and wherein ends of each magnet within the second magnet ring are located at different angular positions than ends of each magnet within the first magnet ring relative to the shaft axis of the shaft. The magnet angle ε is preferably an optimal magnet angle for minimizing cogging torque and line to line back emf harmonics. A method of determining the optimal magnet angle includes determining a first magnet angle where cogging torque is minimized, determining a second magnet angle where harmonic content of n th harmonic is minimized, and using the first magnet angle and the second magnet angle, determining an optimal magnet angle for minimizing both cogging torque and nth harmonic. | 7 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This patent application claims priority on U.S. Provisional Patent Application No. 60/945,602, filed on Jun. 22, 2007.
FIELD OF THE APPLICATION
[0002] The present application relates to installation of roadside railing, and more particularly to an apparatus used in the installation of rails to posts.
BACKGROUND ART
[0003] The installation of roadside railing is a labor-intensive operation, that involves operators supporting and handling rails so as to secure these rails to posts. There are ergonomic issues associated with this type of operation, as operators must show strength to be capable of repeatedly supporting the rails, while having to show dexterity in aligning rails to secure them to one another and fix them to posts.
SUMMARY
[0004] It is therefore an aim of the present disclosure to provide a railing installation apparatus that addresses issues associated with the prior art.
[0005] It is a further aim of the present disclosure to provide a method for installing railing that addresses issues associated with the prior art.
[0006] Therefore, in accordance with the present invention, there is provided a railing installation apparatus comprising: a support platform adapted to be displaced alongside a road; an installation unit connected to the support platform, the installation unit comprising: a feed conveyor unit feeding rails to a carriage unit; and the carriage unit being actuated to orient rails to an installation position against posts, and to twist a series of rails connected at one end to said posts to an overlapping position with rails in the feed conveyor unit for end-to-end attachment of the rails.
[0007] Further in accordance with the present invention, there is provided a method for installing rails on posts, comprising the steps of: providing a sequence of at least two rails secured end to end; fastening an end of one of the rails to a post; and twisting the sequence such that a free end is in position to be secured to an end of another rail.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is a perspective view of a railing installation apparatus in accordance with an embodiment of the present disclosure;
[0009] FIG. 2 is a side elevation view of the railing installation apparatus of FIG. 1 ;
[0010] FIG. 3 is a rear elevation view of the railing installation apparatus of FIG. 1 ;
[0011] FIG. 4 is a top plan view of the railing installation apparatus of FIG. 1 ;
[0012] FIG. 5 is a perspective view of the railing installation apparatus of FIG. 1 , with an installation system extended horizontally and with a rail on a feed conveyor unit;
[0013] FIG. 6 is a perspective view of the railing installation apparatus of FIG. 5 , with the rail reaching a carriage unit;
[0014] FIG. 7 is a perspective view of the railing installation apparatus of FIG. 6 , with rails on the carriage unit and the feed conveyor unit;
[0015] FIG. 8 is a perspective view of the railing installation apparatus of FIG. 1 , during the installation of railing along a road;
[0016] FIG. 9 is a perspective view of the railing apparatus of FIG. 1 , having an optional loading system; and
[0017] FIG. 10 is an enlarged perspective view of the loading system of FIG. 9 .
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0018] Referring now to the drawings, and more particularly to FIG. 1 , a railing installation apparatus is generally shown at 10 . The apparatus 10 has an installation system 11 and a trailer 12 .
[0019] The installation system 11 is used to provide assistance to operators installing the rails, by supporting the weight of the rails to reduce the involvement of the operators in such tasks.
[0020] The trailer 12 supports the installation system 11 and is displaceable alongside the road as the railing is being installed. The trailer 12 supports the stacks of rails A on platform 20 prior to their being installed. In the illustrated embodiment, the trailer 12 is a flat bed that is connected to a motorized vehicle (not shown), but may also be an integral platform of a vehicle (e.g., a truck). Wheels 21 are illustrated in FIG. 1 .
[0021] The installation system 11 has a feed conveyor unit 13 , a carriage unit 14 and an operator station 15 between the feed conveyor unit 13 and the carriage unit 14 .
[0022] The feed conveyor unit 13 is used to supply rails from the stack of rails A to the carriage unit 14 .
[0023] The carriage unit 14 relates the rails A (1) that are connected end to end and mounted to the vertical posts B ( FIG. 8 ) to (2) rails A being individually fed by the feed conveyor unit 13 . The carriage unit 14 orients the rails A toward their installation orientation against the posts B ( FIG. 8 ).
[0024] The operator station 15 is positioned between the feed conveyor unit 13 and the carriage unit 14 , for an operator to secure rails in end-to-end fashion. Moreover, the operator station 15 features the controls by which the operator will actuate various movements of the installation system 11 and the carriage unit 14 .
[0025] The installation system 11 is displaceable horizontally (i.e., along the X-axis) and vertically (i.e., along the Y-axis) with respect to the trailer 12 . More specifically, the installation system has a vertical displacement mechanism 16 and a horizontal displacement mechanism 17 , such that the feed conveyor unit 13 , the carriage unit 14 and the operator station 15 can all be displaced simultaneously. In the illustrated embodiment, the displacement mechanisms 16 and 17 involve telescopic members and hydraulic cylinders, but other similar systems may be used as well. In FIG. 5 , the installation system 11 is shown in an extended position along the X-axis.
[0026] Referring concurrently to FIGS. 1 to 4 , the feed conveyor unit 13 is shown having a conveyor 30 having a series of inline rollers 31 . The rollers 31 are idler rollers (some of which are optionally actuated) that support rails, as is seen in FIG. 5 . The rails are typically of the type having a sinusoidal section, with two valleys and a ridge, as is best seen in FIG. 3 . When the rail A is on the conveyor 30 , the rollers 31 are accommodated in the underside of the ridge, whereby the rail A can simply be manually displaced along the conveyor 30 (i.e., in direction of the Z-axis).
[0027] A stabilizing unit 33 is positioned at a downstream end of the conveyor 30 . The stabilizing unit 33 is a structure supporting additional rollers 34 that are above the rollers 31 . The rollers 34 are positioned so as to be accommodated in the valleys of the rails A, as is shown FIG. 6 . By having rollers 31 and 34 in the valleys and ridge, the rail A in the stabilizing unit 33 will be prevented from moving in the X-axis and in the Y-axis. It is pointed out that the additional rollers 34 may be positionable to a set position to adjust the stabilizing unit 33 to different sizes of rails A. The stabilizing unit 22 has a telescopic support 33 A, by which the stabilizing unit 33 can be displaced vertically (along the Y-axis).
[0028] Referring concurrently to FIGS. 1 to 4 , the carriage unit 14 is in alignment with the conveyor 30 to allow rails A to be transferred from the conveyor 30 to the carriage unit 14 . The carriage unit 14 has a structure 40 that supports lower rollers 41 (in line with the rollers 31 of the conveyor 30 ), and upper rollers 42 (in line with the additional rollers 34 of the stabilizing unit 33 ). The rollers 42 are positioned so as to be accommodated in the valleys of the rails A, whereas the lower rollers 41 are in the underface of the ridge as is shown in FIGS. 6 and 7 . Therefore, when a rail A is in the carriage unit 14 , it is prevented from moving in the directions of the X-axis and the Y-axis.
[0029] The structure 40 of the carriage unit 14 is pivotally mounted to a remainder of the installation system 11 . More specifically, the structure 40 of the carriage unit 14 is mounted to a remainder of the installation system by a pivot joint 43 . Therefore, the structure 40 of the carriage unit 14 is pivotable to an installation position, as illustrated in FIG. 8 . The degree of rotation of the structure 40 of the carriage unit 14 about the Z-axis is actuated by hydraulic cylinders or a motor (not shown).
[0030] The structure 40 of the carriage unit 14 also has a telescopic support 44 ( FIG. 3 ), by which the structure 40 can be displaced vertically (along the Y-axis), independently of the feed conveyor unit 13 . The structure 40 can also be displaced horizontally (along the X-axis) to facilitate the installation of rails A. The horizontal displacement is independent from the horizontal displacement of a remainder of the installation system 11 .
[0031] The operator station 15 has a seat 50 . When seated, an operator is between the stabilizing unit 33 and the carriage unit 14 . Although not shown, it is contemplated to provide a control unit for the operator to control the horizontal and vertical position of the installation system 11 , as well as the orientation of the structure 40 of the carriage unit 14 .
[0032] Now that the components of the railing installation apparatus 10 have been described, an installation of rails to posts is explained.
[0033] It has been noted that rails A can be twisted. More specifically, when two or three rails A are secured end to end, it has been tested that such an assembly of rails A can be twisted along the longitudinal axis by at least 90 degrees. Accordingly, referring to FIG. 8 , while one end of a sequence of end-to-end rails A is secured to a post B 1 amongst posts B, the free end that is supported by the carriage unit 14 can be twisted to the position illustrated in FIG. 7 . Therefore, the installation system 11 is used to interconnect rails A in end-to-end fashion.
[0034] In an embodiment, the installation takes place in the following order. The apparatus 10 is positioned adjacent to posts B, and the vertical and horizontal displacement mechanisms 16 and 17 are actuated to position the installation system 11 close to posts B ( FIG. 8 ).
[0035] Referring to FIG. 5 , a rail A is positioned on the conveyor 30 , and is moved along the Z-axis, through the operator station 15 ( FIG. 6 ), and into the carriage unit 14 . When the rail A is out of the feed conveyor unit 13 and fully supported by the carriage unit 14 , the carriage unit 14 is pivoted to the position illustrated in FIG. 8 .
[0036] Simultaneously, another one of the rails A is positioned on the conveyor 30 and is moved along the Z-axis. As a portion of the rail A extends out of the stabilizing unit 33 of the feed conveyor unit 13 , it overlaps the end of the rail A that is supported by the carriage unit 14 , as is shown in FIG. 7 . When a pair of rails A overlap as is illustrated in FIG. 7 , the operator interconnects the rails A, using appropriate fasteners.
[0037] The connected rails A are then displaced along the Z-axis, with the downstream rail A moving out of the carriage unit 14 , for the upstream rail A moving into the carriage unit 14 to be secured in end-to-end fashion with a subsequent rail A.
[0038] When a sufficient number of rails A extend out of the carriage unit 14 toward the rear of the trailer 12 , another operator may start securing the rails A to the posts B. As is shown in FIG. 8 , the carriage unit 14 is pivoted to the installation position, whereby the rails A extending out of the carriage unit 14 can be connected to posts using appropriate fasteners. The various degrees of freedom of the installation system 11 allow the rails A to be positioned properly with respect to the posts.
[0039] When the rails A are fastened to the posts B, it is necessary that a suitable length of rails from the carriage unit 14 not yet be secured to posts. As is shown in FIG. 8 , between post B 1 and the carriage unit 14 , the rails A are not fastened to the posts B. Accordingly, the carriage unit 14 is pivoted back to the position illustrated in FIG. 7 , thereby twisting a series of rails A as described above, such that an additional rail A may be installed in end-to-end fashion with the sequence of rails A downstream of the operator station 15 . The trailer 12 is displaced along the road as the sequence of rails A is installed to the posts.
[0040] Referring concurrently to FIGS. 9 and 10 , the railing installation apparatus 10 is illustrated as being equipped with a loading system 60 . The loading system 60 is mounted to the horizontal displacement mechanism 17 and is positioned adjacent to the feed conveyor unit 13 . The loading system 60 feeds rails A from the stack to the feed conveyor unit 13 .
[0041] The loading system 60 is in the form of a bridge crane that has a support beam 61 with fingers 62 projecting downwardly therefrom. The support beam 61 translates horizontally and vertically, thus along the X-axis and the Y-axis. These translations are actuated by horizontal actuator 63 (e.g., a rack and pinion assembly with motor 63 A) and vertical actuator 64 (e.g., a rack and pinion assembly with motor 64 A). Actuatable clamps 65 are provided at the bottom end of the fingers 62 to separate then grasp the uppermost rail A from the stack, then raise the rail A, move the rail A to alignment with the feed conveyor unit 13 , and lower the rail A onto the feed conveyor unit 13 . | A railing installation apparatus comprises a support platform adapted to be displaced alongside a road. An installation unit is connected to the support platform. The installation unit comprises a feed conveyor unit feeding rails to a carriage unit. The carriage unit is actuated to orient rails to an installation position against posts, and to twist a series of rails connected at one end to the posts to an overlapping position with rails in the feed conveyor unit for end-to-end attachment of the rails. | 4 |
BACKGROUND OF INVENTION
The invention relates to semiconductor materials and devices characterization or evaluation, and more particularly to the electrical and optical characterization of light emitting diode (LED) device structures. The invention will be described with particular reference to the characterization of quantum well-based LED structures. However, the invention is not so limited, but will also find application in optical and optoelectronic evaluation of p/n junctions, semiconductor laser structures, and the like.
The prior art discloses semiconductor characterization using a very broad range of experimental techniques. Semiconductor materials and devices are commonly characterized or evaluated using x-ray diffractometry, photoluminescence, cathodoluminescence, and electroluminescence, among many other techniques. In the case of optoelectronic devices which convert electrical energy to optical energy and/or vise versa, methods which excite luminescence in the material are particularly useful. In photoluminescence, excess carriers (excess electron-hole pairs) are photoexcited by exposure to a sufficiently intense light source, and the luminescence emitted as these photoexcited carriers recombine is measured. The luminescence can be measured spectroscopically and/or as a function of time after the light source is turned off. Cathodoluminescence is similar to photoluminescence except that the excess carriers are generated by exposure to an electron beam rather than by exposure to light.
For evaluating a light emitting diode (LED) device structure, the electroluminescence behavior is of greatest interest, as the finished LED device functions through electroluminescence. Electroluminescence is similar to photoluminescence and cathodoluminescence, except that in electroluminescence the excess carriers are electrically injected. In the case of an LED, the electrical injection of carriers into the optically active p/n junction region is achieved by forward biasing the p/n junction. However, electroluminescence is not equivalent to photoluminescence, because the electroluminescence behavior of a sample is determined by a number of factors, such as the optical properties of the optically active layers, the electrical transport properties (e.g., conductivity) of the p-type and n-type regions, and the properties of the electrical contacts through which the electrical biasing is applied. Some of these factors, particularly those relating to transport, can produce different effects on the electroluminescence versus the photoluminescence. It is to be appreciated that in photoluminescence, both the excess conduction electrons and the excess holes are typically injected into the same side of the junction, whereas in electroluminescence the injection of electrons and holes are on opposite sides of the junction.
An important class of LED's are epitaxially grown double heterostructure-based LED's (DH-LED's). In these devices, the simple doping junction of the standard p/n diode LED is replaced by an active region containing luminescent material, and with an energy gap less than that of the surrounding p and n type materials. The active region is preferably sandwiched between the p-type and n-type regions of the DH-LED. Light emission in a DH-LED is through the radiative recombination of electrically injected excess carriers inside the active layer. The active layer of a DH-LED defines a potential well. If the dimension of the active layer is less than about 10 nm, then the double heterostructure is called a quantum well. Multiple quantum wells can exist in the active layer of a heterostructure LED.
The active region of a DH-LED serves, in addition to physically hosting the luminescent material, as a carrier confinement region that confines carriers inside the active layer or quantum wells. If an electron-hole pair exists inside a potential well, the likelihood of recombination increases as the width of the well decreases. This is simply because the electron is physically closer to the hole in a narrow potential well than in a wider potential well.
The electroluminescence of DH-LED's and quantum well-based LED's is further complicated by the additional structural complexity. The electroluminescence can be affected by factors such as the effectiveness of the carrier confinement, interfacial defects, impurities at the quantum well boundaries or inside the quantum wells, the relative confinement of conduction electrons versus holes (typically determined by the conduction band and valence band offsets at the interface between the quantum well and the barrier material), crystalline quality of the quantum wells, atomic interdiffusion at the quantum well interfaces, and the like. It will again be appreciated that these effects can be different for electroluminescence versus photoluminescence.
Commercial LED wafers are typically tested at the wafer level using photoluminescence. However, it is generally known to the art that high photoluminescence efficiency is a necessary but not a sufficient test of an LED wafer. A wafer that exhibits poor active layer photoluminescence properties will usually also exhibit poor electroluminescence behavior, translating into poor LED's fabricated therefrom. However, a wafer with high photoluminescence efficiency may or may not produce high electroluminescence efficiency and hence good LED's, because of differences between the electroluminescence and photoluminescence processes as discussed above. Thus, there remains an unfulfilled need for improved screening of LED wafers at the wafer level.
The prior art also does not teach effective means for separating out the various components of the electroluminescence signal. Poor electroluminescence or LED behavior can result from failure at any layer of the LED structure, or from problems introduced during LED fabrication. The prior art teaches generating a matrix of varying sample growth conditions and fabrication steps and analyzing the matrix, e.g. by fabricating LED's therefrom, in the hope of correlating the matrix parameters with changes in the LED behavior or the electroluminescence. This approach has several disadvantages. First, it is expensive in terms of personnel time, equipment load, and source materials. Second, it is highly subjective. Misleading results can easily be obtained if elements of the sample matrix include unknown variations, e.g. differences in doping level between samples for a layer which has the same nominal doping level for all the samples of the matrix. Even if an unintended matrix variation is recognized, e.g. through doping concentration measurements, it still can be difficult or even impossible to correct the data therefor.
In view of these disadvantages, it would be useful to have an improved characterization method that preferably is performed at the wafer level and more closely resembles the physical mechanisms of electroluminescence and LED operation, and that has the ability to independently evaluate for a single sample the relative contributions or effects on the electroluminescence characteristics of the various sample regions such as the active region including the quantum well or wells, the p-type material region, the n-type material region, and the electrical contacts.
The present invention contemplates such an improved characterization or evaluation method and apparatus.
SUMMARY OF INVENTION
In accordance with one aspect of the present invention, an apparatus for evaluating an associated semiconductor sample is disclosed. The associated sample has a first electrically distinct region and a second electrically distinct region, and further has a junction region disposed therebetween. The evaluation apparatus includes a stage for mounting the semiconductor sample. A first laser has a wavelength tuned to photogenerate carriers in the first electrically distinct region. An electrical biasing means is provided for impressing an electrical field whereby at least some photoexcited carriers are influenced to drift toward the junction region. The photoexcited carriers are holes from the p-side and electrons from the n-side. In this manner, instead of injecting electron-hole pairs from one side through thermal diffusion, electrons and holes are injected from different sides as they would be in an actual LED. An optical detector is provided, whereby luminescence generated by recombination of the photoexcited carriers in the junction region is detected.
Preferably, the apparatus includes a translation means for relatively translating the laser and the sample whereby the laser beam is scanned across the sample. A second laser is preferably disposed on the opposite side of the sample with respect to the first laser. The second laser has a wavelength tuned to photogenerate carriers into the second electrically distinct region. Preferably, the first laser has a wavelength tuned to a first energy approximately corresponding to the energy band gap of a material comprising the first electrically distinct region, while the second laser has a wavelength tuned to a second energy approximately corresponding to the energy band gap of a material comprising the second electrically distinct region. Optionally, the two wavelengths can be the same, i.e. the same laser beam is split to serve as both the first laser and the second laser.
In one application, the associated sample has at least one potential well in the junction region. The optical detector preferably has a detection wavelength range which essentially includes the active layer luminescence. In a more specific application, the first region of the associated sample includes n-type gallium nitride, the second region of the associated sample includes p-type gallium nitride, and the active layer of the associated sample includes an alloy of indium gallium nitride. In this case, the first laser and the second laser preferably have wavelengths less than 365 nm to provide adequate absorption by the semiconductor. Preferably, at least one of the group including the first laser and the second laser is a tunable wavelength laser.
In accordance with another aspect of the present invention, a method for characterizing an associated semiconductor sample is disclosed. The associated sample has a first electrically distinct region and a second electrically distinct region, and further has a junction region disposed therebetween. The characterization method includes the steps of optically generating carriers in the first electrically distinct region, generating an externally applied drift field in the first region that effectuates a drifting of the optically generated carriers in the first electrically distinct region toward the junction region, and measuring the optical radiation generated by radiative recombination of the optically generated carriers in the junction region.
Preferably, the characterization method also includes optically generating carriers in the second electrically distinct region, and generating an externally applied drift field in the second region that effectuates a drifting of the optically generated carriers in the second electrically distinct region toward the junction region. Typically, the step of generating an externally applied drift field in the first region and the step of generating an externally applied drift field in the second region are performed together by applying a voltage between an electric contact that electrically contacts the first electrically distinct region and an electric contact that electrically contacts the second electrically distinct region.
In the step of generating an externally applied drift field in the first region, an electric drift field described by a field vector E is generated. Preferably, in the step of optically generating carriers in the first electrically distinct region, the optically generated carriers are substantially generated within a distance d=μτ|E| of the junction region, where μ is the drift mobility of the optically generated carriers in the first material, and τ is the lifetime of the optically generated carriers in the first material. Under these conditions, the fraction of the optically generated carriers which enter the junction region is approximately 1/e.
The method preferably further includes estimating quantitatively the volume recombination rate in the junction region based on the step of measuring the optical radiation generated by radiative recombination of the optically generated carriers in the junction region; estimating quantitatively the volume density of optically generated carriers in the first electrically distinct region; and estimating quantitatively the electroluminescence efficiency based upon the volume recombination rate and the volume density of optically generated carriers.
In the above method, the magnitude of the drift field produced in the step of generating an externally applied drift field in the first region is preferably sufficiently low such that the number of carriers electrically generated is negligible compared to the optically generated carriers.
In accordance with yet another aspect of the present invention, A method for characterizing a light emitting diode (LED) structure sample is disclosed. The sample has an n-type region and a p-type region with a junction region disposed therebetween. Carriers are optically generated in the n-type region by light impingement thereon. Carriers are optically generated in the p-type region by light impingement thereon. The optical radiation generated by radiative recombination of the optically generated carriers in the junction region is measured.
Preferably, the method further includes electrically biasing the junction and to effectuate a drifting of the optically generated carriers toward the junction region.
Preferably, the method further includes optically chopping the impinging light with an optical chopper, detecting the optical radiation with an optical detector, and measuring the optical detector signal at the optical chopping frequency using a lock-in amplifier that is in operative communication with the optical chopper and the optical detector.
Preferably, the method further includes repeating the generating, biasing, and measuring steps at a plurality of wavelengths of the at least one optical source, and estimating transport properties of the at least one region therefrom.
Preferably, the method further includes repeating the generating, biasing, and measuring steps at a plurality of intensities of the at least one optical source, and estimating the effects of high injection levels from the measuring.
One advantage of the present invention is that it permits separately probing the effects of transport in the p-type and n-type regions, artifacts due to the electrical contacts, and properties intrinsic to the active region.
Another advantage of the present invention is that it permits spatial profiling of the LED heterostructure across the wafer.
Another advantage of the present invention is that it permits depth-dependent profiling into both the n-side and the p-side of the LED structure.
Yet another advantage of the present invention is that it facilitates photoexcited electroluminescence whereby simultaneous excitation from the front and the rear of the wafer is performed.
Still yet another advantage of the present invention is that it provides a wafer level characterization method that is closer to the physical behavior of an operating LED versus prior art wafer level characterization methods.
Still further advantages and benefits of the present invention will become apparent to those of ordinary skill in the art upon reading and understanding the following detailed description.
BRIEF DESCRIPTION OF DRAWINGS
The invention may take form in various components and arrangements of components, and in various steps and arrangements of steps. The drawings are only for purposes of illustrating a preferred embodiment and are not to be construed as limiting the invention.
FIG. 1 is a drawing of an experimental apparatus according to one embodiment of the invention.
FIG. 2 is a drawing of the physical processes which occur inside the sample during a method carried out in accordance with the apparatus drawn in FIG. 1 .
FIG. 3 is a drawing of an experimental apparatus according to another embodiment of the invention.
DETAILED DESCRIPTION
With reference to FIG. 1, an experimental apparatus 10 is described in accordance with one embodiment of the invention. The experimental apparatus 10 operates upon an associated LED sample 12 . The associated sample 12 includes a substrate 14 and typically a plurality of semiconductor layers 16 , 18 , 20 usually grown epitaxially thereon. In FIG. 1, an exemplary gallium nitride (GaN) based LED sample 12 is shown, which includes a sapphire substrate 14 , a p-type GaN region 16 and an n-type GaN region 18 . Sandwiched between the p-type GaN region 16 and the n-type GaN region 18 are a plurality of In x Ga 1−x N quantum wells 20 which comprise the active region of the LED device. “Quantum wells” are InGaN layers typically around 10 nm thick or less. Although four quantum wells 20 are drawn, it is to be appreciated that GaN QW-LED's with as few as one InGaN layer are feasible, and the layer need not be a quantum well. The In x Ga 1−x N layers are alloys of InN and GaN, and the mole fraction of InN in the quantum well or wells, denoted by x in the formula In x Ga 1−x N, strongly affects the LED emission peak wavelength, through the band gap of the In x Ga 1−x N material, and through an incompletely understood mechanism involving physical segregation of InN from GaN in the alloy. Additional layers, such as nucleation buffer layers (not shown) are also optionally incorporated to facilitate the crystal growth or for other reasons related to the design and performance of the LED. Of course, the invention is not limited in application to the exemplary GaN-based LED structure drawn in FIG. 1, but will also find application in the characterization of a wide range of LED structures comprising various materials and various layer combinations, as well as in the characterization of other optoelectronic materials and devices such as semiconductor laser device structures.
With continuing reference to FIG. 1, a p-type electrical contact 22 is formed which contacts the p-type region 16 . A series of vias 24 are etched through the p-type region 16 and the quantum wells 20 thereby exposing portions of the n-type region 18 , and n-type electrical contacts 26 are formed therein. It will be appreciated that the p-type electrical contact 22 preferably includes a region which is essentially transparent with respect to the photoexcitation light source which will be described next. In the illustrated embodiment of FIG. 1 this transparent area includes the entire contact 22 area. In a preferred embodiment for a group III-nitride LED, a nickel oxide/gold or cobalt oxide/gold contact is used for the p-type contact 22 . This contact is preferably formed by depositing 5-10 nm of nickel followed by 5-10 nm of gold and annealing the contact at 450-600° C. for 5 minutes in air. The thickness of the gold is sufficiently thin in the region of photoexcitation light impingement to ensure good transparency. Of course, the described contact is exemplary only, and other transparent contacts may be used instead. The vias 24 and the contacts 22 , 26 are preferably formed using standard semiconductor processing techniques well known to those skilled in the art.
It will be appreciated that the fabrication steps just described can be performed at the wafer level in an essentially non-destructive manner. Depending upon the conductivity of the n-type layer or of the underlying substrate, the contact vias are optionally restricted to peripheral areas of the wafer so that the central wafer areas remain undisturbed and available for subsequent commercial LED device fabrication. In one embodiment, the Ni/Au oxidized contact is the first step of the LED fabrication process. In another embodiment, the Ni/Au oxidized contact is selectively removable using standard etching methods that are well known to those of ordinary skill in the art. It will also be appreciated that for conductive substrates such as silicon carbide or gallium nitride, the contact vias 24 are optionally replaced by direct electrical contact to the conductive substrate, further facilitating wafer-level testing.
With continuing reference to FIG. 1, the experimental apparatus 10 includes a first light source 30 which applies a first photoexcitation light 32 to the p-type region 16 through the transparent region of the p-type electrical contact 22 . In a preferred embodiment, the first light source 30 is a laser with a well defined lasing wavelength, although lamp systems with appropriate conditioning optics such as wavelength-selective filters can be substituted therefor. Preferably, a second light source 34 applies a second photoexcitation light 36 in the n-type region 18 . It will again be appreciated that the second photoexcitation light 36 should pass through the substrate 14 without excessive optical attenuation. In the exemplary case of a sapphire substrate, this transparency condition is met for a preferred wavelength range around approximately 365 nm or shorter (sapphire is transparent down to 200 nm) which is appropriate for photoexcitation of the GaN regions 16 , 18 , as well as for the wavelength range around approximately 365 nm or longer which is appropriate for photoexcitation of typical In x Ga 1−x N quantum wells. For partially opaque substrates, the substrate is optionally thinned in the region of interest to obtain sufficient transparency.
With continuing reference to FIG. 1, the experimental apparatus 10 also includes a biasing means 40 for applying a variable electrical bias to the sample 12 . In the apparatus drawn in FIG. 1, the biasing means is a d.c. voltage source 40 , such as a battery with a variable resistor, a commercial d.c. power supply, a custom-built power supply, or the like. The biasing means 40 is preferably connected to the p-type contact 22 by wiring 42 , and to the n-type contacts by wiring 44 . In one embodiment of the invention, the DC bias is applied just below threshold, so that the only spatial region of significant current flow through the active layer is near the photoexcited volume. It will be appreciated that the biasing means can take various other forms.
The experimental apparatus 10 also includes an optical detector 46 which detects luminescence generated by the associated sample 12 under the influence of the experimental apparatus 10 . The detector 46 can be a photomultiplier tube, a photodiode, a diode array, or the like, and also preferably includes a light-collecting lens 48 , optical fiber coupling (not shown), appropriate drive electronics (not shown), and a dispersive component such as a monochromator, spectrograph, or the like.
With continuing reference to FIG. 1, and with further reference to FIG. 2, an exemplary method implemented by the experimental apparatus 10 is described. The first photoexcitation light 32 impinges on the p-type region 16 . For a properly selected wavelength, the photoexcitation light 32 is absorbed primarily in the p-type region 16 . The photon absorption process photogenerates electron-hole pairs. The wavelength is selected to position the photoexcited electron-hole pair distribution essentially within a certain depth range, which is determined by the absorption spectrum of the material or materials comprising the p-type region 16 . In the p-type material 16 , photoexcited majority carrier holes are represented in FIG. 2 by an exemplary hole 50 . Similarly, the second photoexcitation light 36 having a wavelength selected to be absorbed in the n-type region 18 will generate electron-hole pairs therein, and the photoexcited electrons are represented in FIG. 2 by an exemplary electron 52 . It will be appreciated that this excess carrier injection arrangement differs fundamentally from that of conventional photoluminescence, because in conventional photoluminescence one or the other of the light sources is absent, and so transport in one of the cladding layers is not investigated. The optical injection arrangement shown in FIG. 2 more closely resembles the actual operation of the final LED device.
The biasing means 40 generates a voltage 54 across the sample as shown in FIG. 2 . The voltage 54 generates electric fields E p , E n in the bulk p-type 16 and n-type 18 regions, respectively. In FIG. 2, the LED 12 is placed in forward bias corresponding to the typical biasing polarity of an operational LED. However, methods employing the apparatus 10 in which a reverse bias is applied are also contemplated. It will be appreciated that the polarity of the forward bias voltage 54 and of the corresponding impressed electric fields E p , E n are such that both the photoinjected holes 50 and the photoinjected electrons 52 are influenced to move toward the junction region 60 . Within the junction region, an active layer or one or more quantum wells 20 exist. In FIG. 2, a single quantum well 20 is shown for simplicity. The electron and the hole drift under the influence of the applied voltage 54 along paths 64 and 66 for the hole 50 and the electron 52 , respectively. The holes 50 and the electron 52 preferably recombine inside the quantum well and emit a photon represented by a ray 70 which contributes to the sample luminescence collected by the collecting lens 48 and measured by the detector 46 .
For a sufficiently high applied voltage the electrically injected carriers in an LED will be more numerous than the photoexcited carriers. Here, however, lower voltages 54 are typically applied, so that the applied voltage 54 is merely influencing the photoexcited carriers to move toward the junction. Lower applied voltages typically reduce non-ohmic contact behavior so that the sample response is more characteristic of the semiconductor layers rather than the contacts. The local threshold voltage in an LED wafer is depressed by the presence of photoexcited carriers, particularly in the p-type material. In one embodiment, the forward bias 54 is set just below threshold, so that the luminescence will be generated predominantly in the photoexcited volume.
In one exemplary embodiment in which the associated LED structure is a simple p/n homojunction without quantum wells (sample not shown), an appropriate electric field magnitude can be estimated based on the drift velocity v=μ|E| where μ is the drift mobility of the optically generated carriers in the material and |E| is the magnitude of the electric field impressed by the voltage 54 , e.g. the field E p or the field E n . The average distance a carrier moves before recombining is d=vτ=τμ|E| where τ is the carrier lifetime in the material. Based upon such transport estimates, the fraction of photoinjected carriers expected to reach the junction region is estimated. Furthermore, the volume density of photoinjected carriers is obtained from the light intensity and the absorption characteristics of the material. The volume (or areal) recombination rate in the junction region is estimated from the luminescence intensity measured by the detector 46 along with geometrical factors. The electroluminescence efficiency is obtained from the volume (or areal) recombination rate and the volume density of optically generated carriers, taking into account the fraction of carriers which reach the junction region.
The above-described homojunction LED calculations are exemplary only. Particularly in more complex heterojunction-based LED's such as the exemplary GaN LED 12 of FIG. 1, the effectiveness of the bias voltage 54 in driving carriers into the active region (e.g., the p-type region 16 or the n-type region 18 ) will depend upon many factors, such as contact resistance, doping levels, potential barriers in the active region, and et cetera. In FIG. 2, exemplary potential barriers E b can impede injection of carriers into the quantum well 20 . Even in the case of a homojunction LED complexities can arise due to impurities, non-uniform dopant distributions, and the like. Because of the complexity of a typical LED samples, quantitative calculations are often impractical in practice. However, by varying selected operational parameters of the apparatus 10 while holding other operational parameters constant, as described next, the individual electroluminescence contributions of the various structural regions of the sample can be separately and independently examined.
With continuing reference to FIGS. 1 and 2, a typical evaluation or characterization of an associated sample such as the exemplary GaN LED 12 using the exemplary method and apparatus of FIGS. 1 and 2 is described. For some measurements, the first and second light sources 30 , 34 of the apparatus 10 are preferably wavelength-tunable sources. By obtaining data for several wavelengths of the first light source 30 while holding the other operational parameters of the apparatus 10 constant (e.g., constant electrical bias 54 , constant intensity and wavelength for the second light source 34 ), the carrier injection from the p-type region 16 is investigated. Varying the wavelength varies the depth of the photoinjected carriers, so that the electroluminescence variation with the wavelength of the first light source 30 correlates with the carrier transport properties of the p-type region 16 . Such measurements also can provide information about potential barriers E b which may be impeding carrier injection from the p-type region 16 into the junction region 60 . In an analogous manner, varying the second light source 34 while holding the other operational parameters constant probes carrier injection from the n-type region 18 .
In another characterization aspect, by increasing the intensity of light sources 30 , 34 together or independently, the effects of high injection levels into one or both regions 16 , 18 is probed essentially independently from contact behavior artifacts which are usually produced at high current levels. In yet another variation, keeping the light sources constant while varying the applied voltage 54 probes factors whose effect on the electroluminescence correlate with high bias voltage 54 . For example, the effects of high contact resistances at the contacts 22 , 26 can be investigated in this manner.
For sufficiently long wavelengths, the absorption typically takes place predominantly inside the quantum wells. Considering the exemplary GaN QW-LED 12 , the p-type and n-type regions 16 , 18 are comprised of GaN while the quantum wells are comprised of In x Ga 1−x N material which has a lower-band gap. Under selected long wavelength conditions, absorption occurs primarily in the In x Ga 1−x N and so transport through the p-type and n-type regions 16 , 18 is essentially irrelevant. The luminescence properties of the active region as a function of applied electrical bias can thus be evaluated directly and independently from the cladding regions 16 , 18 .
In the apparatus 10 , the associated sample 12 is preferably mounted on a translation stage (not shown) whereby the sample 12 is moved laterally with respect to the light sources 30 , 34 . In this way, lateral inhomogeneities can be probed. Lateral translation is often useful for detecting variations in quantum well thickness across the wafer, for example. Material damage near an alloyed contact can also be evaluated by scanning the injection region toward the contact.
In the apparatus embodiment of FIG. 7, two independent light sources 30 , 34 are used to inject carriers into the p-type region 16 and the n-type region 78 , respectively. This approach enables the use of different wavelengths for exciting the two sides of the junction. The two excitation beams optionally have different coordinates in the horizontal plane so as to probe lateral diffusion and drift effects; also the two excitation beams are optionally pulsed, with pulse width short compared to carrier lifetime so as to probe temporal drift, diffusion, and recombination effects; furthermore the pulses need not be coincident, so as to independently probe temporal drift, diffusion, and recombination effects in the n and p type material. However, in many cases the two sides are comprised of the same material, e.g. GaN. For such samples, separate wavelength adjustment capability for each of the two sides of the junction may not be particularly advantageous.
With reference to FIG. 3, a second apparatus embodiment 100 of the invention is described. The embodiment is shown acting on the same exemplary GaN-based sample 12 as is shown in FIG. 7 . The biasing arrangement, comprising variable biasing means 140 and wiring 742 , 144 is preferably essentially unchanged from the embodiment of FIG. 1 . However, the two light sources 30 , 34 of the embodiment of FIG. 1 are replaced in the embodiment of FIG. 3 by a single light source 130 with a beam splitter 132 , several mirrors 134 , and two variable intensity attenuators 136 which can take the form of filter wheels, removably insertable neutral density filters, shutters, or the like. The single light source 130 is preferably an adjustable wavelength light source.
The light detection is preferably by an optical detector 146 and a light collecting lens 148 , both of which are similar to the corresponding components of the first apparatus of FIG. 1 . However, because a single light source is used, the apparatus of FIG. 3 optionally includes a lock-in detection sub-system including an optical chopper 150 and a lock-in amplifier 152 in operative communication with the optical chopper 150 and the optical detector 146 . As is known to those skilled in the art, use of lock-in detection greatly increases the signal-to-noise ratio of the detected luminescence signal. Of course, other signal detection sub-systems can be substituted therefor.
The methods described with respect to the apparatus of FIG. 1 are also generally compatible with the apparatus of FIG. 3 . However, with the apparatus of FIG. 3 the wavelength of light impinging on the p-type region 16 and the n-type region 18 cannot be independently varied. The relative light intensities are, however, independently variable through the two variable attenuators 136 , and so the magnitude of the carrier injection into the two regions 16 , 18 can be independently controlled.
The invention has been described with reference to the preferred embodiments. Obviously, modifications and alterations will occur to others upon reading and understanding the preceding detailed description. It is intended that the invention be construed as including all such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof. | An apparatus for evaluating an associated semiconductor sample having two electrically distinct regions with a junction region disposed therebetween includes a laser for injecting carriers into a sample region, an electrical bias for impressing electrical fields on the sample, and a detector for detecting luminescence. A second laser is provided for injecting carriers into a second sample region opposite the first region. A method includes the steps of: optically generating carriers in a region, generating a drift field in the region that effectuates carrier drift toward the junction, and measuring the optical radiation generated by carrier recombination in the junction region. Preferably, the method also includes optically generating carriers in a second region and generating a drift field in the second region that effectuates carrier drift toward the junction. Typically, the two drift fields are generated together by applying voltage between the two regions. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims benefit of priority to German Application No. DE 10 2006 030 427.6-21, filed Jun. 29, 2006, which is owned by the assignee of the instant application. The disclosure of German Application No. DE 10 2006 030 427.6-21 is incorporated herein by reference in its entirety.
FIELD OF THE INVENTION
[0002] In general, in one embodiment the invention relates to a multi-flexible manufacturing plant for assemblies, to be joined together from several pre-fabricated parts, of vehicle bodies.
BACKGROUND
[0003] It is a well-known fact that manufacturing plants designed for a particular type of vehicle only achieve their full potential, when a new model is introduced, after a certain start-up phase and, when a model change is imminent, operate at less than full capacity. Such operation of a manufacturing plant is not economical. Therefore there are considerations as to how the economy of the manufacturing plant can be improved in the startup phase and final phase of a vehicle model.
[0004] Furthermore it is only possible, to a quite limited extent, to run a manufacturing plant with different vehicle models or pre-fabricated part types (in the following abbreviated to “types”). In order to run a manufacturing plant at full capacity it would therefore also be desirable to use it to produce a mix of different types.
[0005] Processing a free mix of different pre-fabricated part types is possible to a limited extent with a known manufacturing plant (DE 298 13 669 U1). With this manufacturing plant the different pre-fabricated part types are supplied via pre-fabricated part feeders arranged separately next to each other or one above the other. By means of a multi-axial handling robot the prefabricated part types are transferred onto individual dollies, which can move to and fro transverse to the material flow direction, so that a dolly with one type of pre-fabricated part is located in each case at a workstation, while the other or others are in quiescent position. Each type of pre-fabricated part is held centrally in a lower tool on the dolly, which having an upper tool designed as gripper forms a clamping device. The gripper is detachably connected to a robot. The space requirement of such a manufacturing plant depends on the number of pre-fabricated part types to be processed. In addition a great amount of space is needed for the transverse movement of the dollies. For this reason the simultaneous mixed production of a plurality of pre-fabricated part types in such a manufacturing plant is possible with reasonable technical expenditure and floor space requirement.
[0006] In another known manufacturing plant for different prefabricated part types (DE 203 04 022 U1) processing stations, which in each case have several working locations for different pre-fabricated part types, are arranged along a transfer line. In order to be able to carry out work on the pre-fabricated parts at these various working locations, processing robots are displaceably arranged on axes of travel along the transfer line. Handling robots with which the prefabricated parts can be fed to and removed from the different working stations are also displaceably arranged on these axes of travel. With this manufacturing plant a great amount of floor space for the processing robots, arranged displaceably along the axis of travel, and working locations for the different pre-fabricated part types is needed. Although the majority of pre-fabricated part types can be processed through a correspondingly large number of workstations, the floor space needed for this is very great.
SUMMARY OF THE INVENTION
[0007] In one embodiment, the invention provides a multi-flexible manufacturing plant for assemblies of vehicle bodies, which permits simultaneous production of different models.
[0008] In accordance with an embodiment of the invention, a multi-flexible manufacturing plant for assemblies, to be joined together from several pre-fabricated parts, of vehicle bodies or body components includes a turntable, on which pick-up and clamping devices for similar or various types of assemblies are interchangeably arranged at several working locations, having an interchange station located next to the turntable, with which a pick-up and a clamping device for a first type of assembly is arranged on the turntable, so it can be replaced by a pick-up and clamping device for another type of assembly. The plant has several processing robots for joining operations and several processing robots, which can be fitted with grippers for specific types of pre-fabricated parts in order to draw pre-fabricated parts from pre-fabricated part magazines and to load and unload the pick-up and clamping device with these pre-fabricated parts as well as with gripper interchange magazines for the specific pre-fabricated part grippers. Both the interchange station for the pick-up and clamping device and the gripper interchange magazines for the grippers are arranged at the outer edge of the plant components, forming an equipment cluster, of turntable, processing robots, gripper interchange magazines and pre-fabricated part magazines, so that they can be supplied from outside with pick-up and clamping devices and grippers.
[0009] With the manufacturing plant according to the invention various types of assemblies of vehicle bodies can be produced simultaneously. Theoretically the number of types which can be produced on the manufacturing plant is unlimited. By “simultaneously” one understands not only a complete mix, that is to say all the different types are produced with constant alternation, but also production, wherein initially only a first type is produced and then a second type and then a third type and so on, which is called “batch production”. Such multiflexibility of the manufacturing plant relies on the fact that the core section of the plant remains unchanged for all types, while the part-specific plant components are replaced as required. Since the components specific to the type of pre-fabricated part are supplied from outside, the number of types to be produced simultaneously is arbitrary. The supply of the components specific to the type of pre-fabricated part from outside also means with routine operation of the manufacturing plant that workers, who procure the components from outside do not have to enter the danger zone of the manufacturing plant.
[0010] In order to be able to perform joining operations on assemblies held on the working locations of the turntable, processing robots are usually arranged outside the turntable. However in order at the same time to also be able to perform joining operations on the inside of the assemblies, a further processing robot can be arranged in the middle of the turntable or approaching from above that is to say sweeping over the pick-up and clamping device.
[0011] The equipping from outside of the pick-up and clamping devices specific to the type of pre-fabricated part and the associated grippers is facilitated if the interchange station is set up for simultaneous uptake of the pick-up and clamping devices and the associated grippers. In the case of this arrangement the associated processing robot can then remove the gripper from the pick-up and clamping device already held in the turntable and transfer it to the gripper interchange magazine.
[0012] If batch production takes place on the plant, that is to say the pick-up and clamping device and the grippers do not need to be changed constantly, a simple interchange station, by which the pick-up and clamping device can be equipped with the associated gripper directly from outside, is sufficient for re-equipping a working location. If however frequent changes are necessary for the different types, such a change can be accomplished more easily with an interchange station for the pick-up and clamping devices, which is designed as exchange turntable with several storage locations. The change of pick-up and clamping device and gripper on a working location of the turntable is then unconnected with a change of pick-up and clamping device with gripper from outside.
[0013] Preferably the exchange turntable has a unit, which can be replaced by the turntable with working locations, in particular a telescopic or pivoting push or swing unit for the pick-up and clamping devices. In this way vibration-free changeover is possible. The joining operations therefore do not need to be interrupted for this.
[0014] A manufacturing plant, which is designed not just with a single production line but with a dual production line, is particularly advantageous. Such a plant can be realized according to one embodiment of the invention with configuration of the different plant components in mirror image, by the processing robots, set up for joining operations, being arranged on a common turntable between the turntables with working locations. Such a manufacturing plant is particularly advantageous, although not exclusively, for simultaneous production of two different types (for example right-hand/left-hand parts) of assemblies.
[0015] According to another embodiment of the invention a finishing station with at least one interchangeable gripper for specific types of pre-fabricated part and at least one processing robot for joining operations is arranged between an unloading station for the joined assemblies and the turntable or turntables with the working locations. The final joining operations can be performed in this finishing station, possibly while the assembly is completed with further pre-fabricated parts, which could not be carried out in the turntables with the working locations.
[0016] In the case of dual production lines the finishing station should have two processing robots for joining operations on a turntable and two grippers for specific types of pre-fabricated parts facing these in mirror image.
[0017] The finishing station is assigned a processing robot, which is set up for drawing the finished assemblies including grippers holding them, from the finishing station and for separate placement of the assemblies in a pre-fabricated part magazine and the gripper in an automatic gripper changer.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] The invention is described below in detail on the basis of a drawing, which shows a manufacturing plant in plan view by way of schematic illustration.
DESCRIPTION
[0019] The illustrated manufacturing plant is designed with a dual production line. It comprises two turntables 1 , 2 , which can be interchangeably equipped in each case on three working locations 3 , 4 , 5 , 6 , 7 , 8 with prefabricated part-specific pick-up and clamping devices 9 , 10 , 11 , 12 , 13 , 14 for assemblies of vehicle bodies, for example side panels. If the clamping devices 9 to 14 are designed for various types of assemblies, a maximum of 6 types of assemblies can be produced simultaneously without changing the equipment of the working locations 3 to 8 .
[0020] A center processing robot 15 a , 15 b is arranged in the center of the turntable 1 , 2 for joining operations on the assemblies. A further turntable 16 , which is equipped with two processing robots 17 , 18 for further joining operations on the assemblies of the turntable 1 , 2 held by the pick-up and clamping devices 9 to 14 , is positioned between the turntables 1 , 2 . The processing robots 17 , 18 can perform a pivotal turn on the turntable 16 . While the processing center robots 15 a , 15 b are designed for joining operations on the inside of the assemblies, or approaching from above, that is to say sweeping around the pick-up and clamping device, the processing robots 17 , 18 are intended for joining operations on the outside of the assemblies. The arrangement of the processing robots 17 , 18 on the turntable 16 on the one hand and their capacity to pivot on the other hand renders the possibility of positioning them optimally for joining operations on both assemblies in turntable 1 and also on assemblies in turntable 2 .
[0021] Each turntable 1 , 2 is assigned an interchange station 19 , 20 for pick-up and clamping devices specific to the type of pre-fabricated part. The interchange magazines 19 , 20 are designed as turntables and in each case comprise four storage locations 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , of which three storage locations 21 to 23 , 25 to 27 are equipped with pick-up and clamping devices 29 , 30 , 31 , 32 , 33 , 34 specific to the type of pre-fabricated part. The fourth empty storage location 24 , 28 serves for taking up a no longer required pick-up and clamping device of turntable 1 , 2 .
[0022] A finishing station 35 , which comprises a turntable 36 with two processing robots 37 , 38 rotatably mounted thereon is located next to the turntable 16 with the two processing robots 17 , 18 for joining operations. Two stationary but interchangeable grippers for specific types of pre-fabricated parts 39 , 40 are arranged on either side of the turntable 36 for the generally completed assemblies coming from turntables 1 , 2 . The interchangeable grippers 39 , 40 can be drawn from an automatic gripper changer 44 . In the finishing station 35 further pre-fabricated parts from a pre-fabricated part magazine 41 can be inserted into these for completion of the assemblies.
[0023] A processing robot 42 , which takes the grippers 39 , 37 , together with the assemblies of the finishing station 35 , places the assemblies in an unloading station 43 and if necessary, due to other types of assemblies, changes the grippers 39 , 40 in the automatic gripper changer 44 , serves for drawing the further pre-fabricated parts from the pre-fabricated part magazine 41 and the final assemblies from the finishing station 35 . The automatic gripper changer 44 also contains suitable grippers for any further pre-fabricated parts with which the processing robot 42 may be loaded.
[0024] Each turntable 1 , 2 with its working locations 3 - 8 is assigned a pre-fabricated part magazine 45 , 46 with storage locations 47 , 48 , 49 , 50 , 51 , 52 specific to the type of pre-fabricated part. A processing robot 53 , 54 , which can move linearly between magazines 45 , 46 and turntables 1 , 2 serves for loading the pick-up and clamping devices 9 - 14 with pre-fabricated parts from magazines 45 , 46 . A stationary joining station 55 , 56 , with which initial joining operations can be performed on the pre-fabricated part held by the processing robot 53 , 54 is arranged on the travel of said processing robot 53 , 54 .
[0025] Processing robots 57 , 58 serve for handing over generally completed assemblies at the working locations 3 to 8 of the turntables 1 , 2 to the finishing station 35 . In order to be able to equip the processing robots 57 , 58 with different grippers for the various types of assemblies, they are each assigned a gripper interchange magazine 59 , 60 designed as a turntable. These gripper interchange magazines 59 , 60 are loaded with precisely the no longer required grippers, which the processing robots 57 , 58 remove from the pick-up and clamping devices 9 to 14 of turntables 1 , 2 .
[0026] The linearly displaceable processing robots 53 , 54 , with which the various types of assemblies are taken from the pre-fabricated part magazines 46 , 47 and handed over to the pick-up and clamping devices 9 to 14 of the turntables 1 , 2 , are assigned gripper interchange magazines 61 , 62 likewise designed as turntables.
[0027] The entire manufacturing plant with its components 1 , 2 , 16 , 19 , 20 , 41 to 46 , 53 , 54 , 57 to 62 ; forming an equipment cluster, is surrounded by a safety guard G. It is only accessible at a few places, where plant components specific to the type of pre-fabricated part, such as grippers and pick-up and clamping devices or smaller pre-fabricated parts, must be introduced into the equipment cluster via gates T 1 , T 2 , T 3 , T 4 , T 5 , T 6 , T 7 , T 8 , so that workers do not have to enter the internal danger zone of the equipment cluster during routine production in order to equip the individual components for the specific type of pre-fabricated part and to feed in prefabricated parts. All work is performed outside the equipment cluster. Inside the cluster the plant components operate “autonomously”.
[0028] With the configuration illustrated in the drawing six different types can be produced on the plant both in the upper and as well as in the lower line, without further components having to be supplied from outside. Thus the turntables 1 , 2 are already equipped with pick-up and clamping devices 3 to 12 for three various types of assemblies in each case. If a further type is to be produced, the no longer required pick-up and clamping device, for example the clamping device 11 , 13 together with its gripper taken by the processing robot 57 , 58 possibly from the gripper interchange magazine 59 , 60 is transferred by means of a not illustrated loading table from the turntable 1 , 2 to the empty storage location 24 , 28 of the interchange station 19 , 20 . After rotation of the interchange station 19 , 20 the necessary new pick-up and clamping device, for example 29 , 34 together with the associated gripper can then be transferred to the turntable 1 , 2 by means of the loading table. The gripper is then removed from the pick-up and clamping device and possibly placed in the gripper interchange magazine 59 , 60 by means of the processing robot 57 , 58 . If the pick-up and clamping device 11 , 13 taken from the turntable 1 , 2 is absolutely no longer required, it can be removed out of the interchange station 19 , 20 through a loading machine operated by a worker via the opened gate T 1 , T 2 and the storage location can be equipped with a new pick-up and clamping device for a new type, which is needed next. The new pick-up and clamping device is transferred to the interchange station from outside through the loading machine operated by the worker via the opened gate T 1 , T 2 .
[0029] The pick-up and clamping devices 9 to 14 of the turntables 1 , 2 are loaded with various types of assemblies from pre-fabricated part magazines 45 , 46 by means of the processing robots 53 , 54 . For this purpose said processing robots 53 , 54 can be equipped with the suitable grippers from gripper interchange magazines 61 , 62 . The gripper interchange magazines 61 , 62 are loaded with various types of grippers from outside via the opened gates T 3 , T 4 by a worker. Further pre-fabricated parts can be added if necessary to the incomplete assemblies held by pick-up and clamping devices 9 to 14 through workers via adjacent gates T 5 , T 6 . Initial joining operations can be performed on assemblies en route to the turntables 1 , 2 at the stationary joining stations. The main joining operations however are performed on assemblies held by the pick-up and clamping devices 9 to 14 through the central processing robots 15 a , 15 b and the outside processing robots 17 , 18 . For this purpose the processing robots 17 , 18 are optimally positioned on their turntable 16 for the assemblies to be joined together. Optimum positioning is possible since the processing robots 17 , 18 can be pivoted not only around their own axis of rotation but also on the turntable 16 , so that the correct joining tools are also in the proper position for the assemblies.
[0030] After completion of joining the processing robots 57 , 58 with suitable grippers drawn from the gripper interchange magazines 59 , 60 take the assemblies alternately from the pick-up and clamping devices 9 to 14 of the turntables 1 , 2 . While the processing robot 58 takes an assembly from the pick-up and clamping device 14 for example, joining operations still continue on the assembly aligned to the processing robots 17 , 18 correctly for joining. The assemblies taken are transferred to the stationary grippers 39 , 40 in the finishing station 35 , where they are finally joined together if necessary after completion with further pre-fabricated parts from the prefabricated part magazine 41 by means of the processing robots 37 , 38 . Also in this case the processing robots 37 , 38 because of rotation of the turntable 36 and their ability to pivot on the turntable 36 can be optimally positioned for the assembly held by the grippers 39 or 40 . After final completion the processing robot 42 takes the assembly together with grippers 39 , 40 from the finishing station 35 and places the assembly in the unloading station 43 . Depending upon the type of assembly to be taken accordingly from the finishing station 35 , the processing robot 42 keeps the gripper or exchanges it in the automatic gripper changer 44 . | A manufacturing plant, in accordance with one embodiment, includes a turntable, interchangeable pick-up, and clamping devices for assemblies at several working locations. The pick-up and clamping devices are assigned at least one processing robot, set up for joining operations, which performs the joining operations on the assemblies held by the pick-up and clamping devices. The turntables 1, 2 are assigned interchange stations, with which the pick-up and clamping devices on turntables can be replaced by others. The interchange stations are preferably designed as turntables with different storage locations for the pickup and clamping devices to be replaced. The different pick-up and clamping devices needed for processing various types of assemblies as well as grippers for the handling robots are introduced exclusively from outside in exactly the same way as the pre-fabricated parts being processed, if a change from one type of assemblies to another type is required. | 8 |
CROSS REFERENCE TO RELATED APPLICATIONS
Not Applicable
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH AND DEVELOPMENT
Not Applicable
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to paddles for use with tabletop games and, in particular, to an angleable paddle for use with a soccer game played on a planar surface.
2. Description of the Prior Art
Tabletop soccer games have a tradition of popularity because of the “action” of a fast moving ball, the challenge to the individual player's quickness of response, and the benefit from physical effort to manipulate the various mechanisms used to move the ball.
However, in the prior art, the mechanisms used to propel the ball do not produce sufficient ball speed for a truly fast action game. For example, U.S. Pat. Nos. 5,372,364, 5,092,595 and 4,300,766 use cue sticks, rotating rods and bats, respectively. These apparatus move the ball about, but not at the velocities that would make the game “action packed”.
Often, these games have numerous fixed and moveable obstacles that a player's ball must circumvent in order to score a goal. Circumventing obstacles requires skill, as opposed to games that are based more on fast action.
While skill games are fun for many people, they are a different type of game in that skill replaces luck. For people who prefer action and luck to skill, the higher ‘skill to luck’ ratio of the obstacle type games, diminishes the fun for these players.
Moreover, a player's physical movement is an inherent aspect of the excitement of fast action soccer table type games. However, the prior art is typically limited only to hand movements. These hand movements lack sufficient player's whole body physical workout. Experiencing a substantial physical workout is preferable in any recreational activity.
BRIEF DESCRIPTION OF THE INVENTION
The instant invention overcomes these difficulties. It is a tabletop soccer game played by two people. The soccer game apparatus includes a flat rectangular playing surface surrounded by upright walls. Goal pockets are placed near the four corners. A movable object, such as a ball or puck, is moved by a pair of double handled, angling paddles used by the players to move or strike the movable object upon the playing surface. The goal pockets are large enough to allow the movable object to pass through, thereby making a goal and scoring a point.
A line inscribed on the playing surface, midway between the long ends of the playing surface, defines two secure zones, in which the opposing player cannot use their soccer paddle to seize the movable object.
The double handled, angling soccer paddle has two rods that serve as handles, hinged to a soccer paddle plate. A player holds the one of the rods in each hand. The player then applies force against the rods to angle the paddle, left or right, to propel the movable object across the playing surface. This is accomplished by pushing on one rod and pulling on the other, which causes the face of the paddle to slant at an angle with respect to the movable object. By moving the handles, quickly, the paddle plate is snapped against the ball at a high rate of speed. This snapping action produces a significant force on the ball, which propels it across the playing surface at a high speed.
This striking force against a wood or plastic ball results in ball acceleration to very high velocities across the playing surface, enabling the ball to ricochet against the walls repeatedly about the playing surface.
In use, a player also uses the doubled handled angling soccer paddle to defend the player's goal pockets by blocking either of the two goal pockets located on their end of the playing surface. Either player can capture and manipulate the ball under their control anywhere within their respective secure zone, positioning the ball for a soccer shot towards the opposing player's goal pockets located at the opposing end of the playing surface. A player also may choose to hit the ball while it is in high-speed motion approaching their end of the playing surface.
Defending two goal pockets from a high-speed ball, traveling unimpeded across the playing surface, produces an impulse response from the player. Hence, much of this present invention is played on impulse; therein, resulting in a ‘high luck to skill’ ratio, yielding much childlike fun trying to keep up with the ball.
Further, if a player engages the full force of both arms, shoulders and upper torso in the application of striking the ball with the double handled angling paddle, they can impact the ball to produce ultra high velocities that rocket the ball across the playing surface.
The objective of each player is to score a goal by causing the ball to enter one of the goal pockets located at the opposite end of the paying surface guarded by the opposing player. The first player to score a set number of goals (e.g., ten goals) is considered the winner.
Half the fun of this game is to keep impacting the ball as hard as possible to keep it moving faster than the opposing player can defend both goal pockets, until the ball either finds a targeted goal pocket, or is captured by the opposing player. This creates a ‘frenzy of action’ that provides more fun for many players than the games described in the prior art.
With an unobstructed playing surface and a high speed ricocheting ball propelling about the playing surface from the powerful snapping action of the double handled angling soccer paddle, the action of play is fast, challenging, fun and a physically beneficial activity.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a tabletop playing surface of one embodiment of the instant invention.
FIG. 2 is a rear perspective view of the double handled angling soccer paddle.
FIG. 3 is a top view of the double handled angling soccer paddle in a first position.
FIG. 4 is a top view of the double handled angling soccer paddle in a second position.
FIG. 5 is a top view of the double handled angling soccer paddle in a third position.
FIG. 6 is a perspective view of a tabletop playing surface of a second embodiment of the instant invention.
FIG. 7 is a side elevation view of the tabletop playing surface showing the goal pockets and support legs.
FIG. 8 is a side elevation view of the tabletop playing surface showing the goal pockets and support legs for use on a tabletop.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to FIG. 1 , a first embodiment of the soccer game apparatus 1 of the present invention is shown. It has a flat, generally rectangular playing surface 10 having oppositely disposed peripheral sidewalls 11 and shorter end walls 12 forming a generally rectangular frame around the playing area. In this embodiment, the playing surface 10 has circular apertures 14 that form the goal pockets for receiving the soccer ball 22 . In the preferred embodiment, the four goal pockets 14 are positioned around the corners of the playing surface, but spaced apart from the corners as shown.
Note that this figure also shows two paddles 20 , one of which is being applied to the ball 22 , as would be typical during game play.
A suitable receptacle 28 is positioned beneath the playing surface for retaining the soccer ball after it passes through the respective goal pocket 14 . See, e.g., FIG. 7 .
A dashed line 13 is inscribed and bisects the playing surface between the end walls 12 to define players' respective secure zone.
The playing surface 10 and walls 11 and 12 may be constructed of wood, plastic or metal. The spherical soccer ball 22 may be made of solid wood, solid plastic, or hollow plastic or a rubber coated material. Although the ball 22 is preferred, it is possible to use other objects on the playing surface as well.
FIG. 2 shows a rear view of one of the doubled handled angling soccer paddles. Each paddle has a pair of rods 16 and 17 . The rods 16 and 17 are pivotally connected to the paddle plate 20 by hinges 18 and 19 that act as pivot points. The rods 16 and 17 have grips 21 for the convenience of player gripping. The hinges 18 and 19 can be hinging brackets, as shown in FIG. 2 . As shown, two curved metal brackets are provided. The rods 16 and 17 have bent ends 26 that are placed within the curved metal brackets, which are in turn, attached to the back of the paddle plate 20 as shown.
The brackets may be held to the paddle with screws or other fasteners known in the art. These hinges provide a good hinging action, good mechanical integrity, and ease of manufacture. However, other hinges or pivot point type structures can be used. These types of hinges are well known in the art. Note that the hinges are placed close together, as shown, in the preferred embodiment. In this way, the rods can impart the greatest amount of “snapping” action that propels the ball at a high rate of speed.
The paddle plate 20 , the rods 16 and 17 and the hinges 18 and 19 , should be made of strong material, e.g., wood, metal, plastic or a combination thereof.
The shape of the paddle plate 20 is generally broad enough and high enough to strike a ball from either side of its outer faces, narrow enough to be light in weight, and strong and durable enough to sustain the shock from impacting a solid wood or solid plastic ball. Within the previously mentioned guidelines, the specific shape or curvature of the paddle plate 20 is relatively unimportant.
FIG. 3 shows the paddle in a neutral position. In this position, the paddle 20 is parallel with the centerline 13 of the table. This is a position in which a player attempts to defend a goal pocket from a fast approaching soccer ball.
FIGS. 4 and 5 show the extreme angled positions of the paddle 20 . These positions result from a swift push/pull motion of rods 16 and 17 . For example, in FIG. 4 , rod 16 is quickly pushed forward and rod 17 is simultaneously pulled back quickly. In FIG. 5 , the motion is opposite to that of FIG. 4 . As noted above, this action produces a snapping of the paddle plate 20 .
The snapping movement of the rods produces a forceful impact against a ball that is positioned on the outer surface of the paddle plate 20 . This force then propels the ball in whatever direction is established by the particular angle of the rods. Note that FIGS. 4 and 5 show the extreme angles. During play, at any given time, the angles may be reduced to produce a different trajectory. Moreover, under actual playing conditions, the ball is moving very quickly. This causes an impulse reaction on the part of the player that, in turn, produces somewhat unpredictable ball movement. With practice, a player can learn to angle the ball, thereby setting up more chances to score points.
Although the paddles are best used on a tabletop game as shown in FIG. 1 , with the goal pockets not in the corners, it is possible to use the paddles on other game surfaces. For example, FIG. 6 is a perspective view of a second embodiment of the tabletop-playing surface. In this embodiment, the table surface and 10 sidewalls 11 and 12 are identical to that of the first embodiment. Here, however, the goal pockets 14 are formed in the end walls 12 , instead of being in the playing surface as before. This figure also shows diagonal braces 30 that provide additional strength as well as providing additional deflecting surfaces for the ball.
FIG. 7 is a side elevation view of the tabletop playing surface showing the goal pockets 28 and support legs 35 . As mentioned above, the goal pockets 14 have receptacles 28 that attach to the bottom of the playing surface 10 . Of course, the placement of the receptacles would vary, depending on the exact placement of the goal pockets shown in the different embodiments. Such changes are well within the art. This figure also shows a ball 22 in one of the receptacles 28 . Finally, legs 35 are shown positioned on the corners of the tabletop. The legs permit the game to be freestanding and are designed to hold the tabletop at a convenient playing height.
FIG. 8 is a side elevation view of the tabletop playing surface showing the goal pockets 28 and support legs 29 for use on a tabletop. Here, the legs 29 are short and are designed to hold the game table up off a surface, such as a large table. This provides space for the receptacles 28 to fit under the table surface as shown.
The present disclosure should not be construed in any limited sense other than that limited by the scope of the claims having regard to the teachings herein and the prior art being apparent with the preferred form of the invention disclosed herein and which reveals details of structure of a preferred form necessary for a better understanding of the invention and may be subject to change by skilled persons within the scope of the invention without departing from the concept thereof. | The invention is a double handled angling paddle for use with a soccer table-top game apparatus, which includes a planar rectangular base area to serve as a playing surface with upstanding sides defining the boundaries of said playing surface, two pair of goal pockets positioned at opposite ends of the playing surface, and a movable object. Two, double-handled angling paddles are used to propel the movable object about on the playing surface. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
The present application is a continuation of application Ser. No. 10/306,003, filed Nov. 29, 2002, now U.S. Pat. No. 7,141,162 which is incorporated herein in its entirety.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to bitumen recovery from oil sand and more particularly to a treatment process for the removal of water and mineral from the product produced in a primary oil sand bitumen extraction process.
2. Description of the Related Art
Oil sands are a geological formation, which are also known as tar sands or bituminous sands. The oil sands deposits provide aggregates of solids such as sand, clay mineral plus water and bitumen—a term for extra heavy oil. Significant deposits of oil sands are found in Northern Alberta in Canada and extend across an area of more than thirteen thousand square miles. The oil sands formation extends from the surface or zero depth to depths of two thousand feet below overburden. The oil sands deposits are measured in billions of barrels equivalent of oil and represent a significant portion of the worldwide reserves of conventional and non-conventional oil reserves.
The oil sands deposits are composed primarily of particulate silica mineral material. The bitumen content varies from about 5% to 21% by weight of the formation material, with a typical content of about 12% by weight. The mineral portion of the oil sands formations generally includes clay and silt ranging from about 1% to 50% by weight and more typically 10% to 30% by weight as well as a small amount of water in quantities ranging between 1% and 10% by weight. The in-situ bitumen is quite viscous, generally has an API gravity of about 6 degrees to 8 degrees and typically includes 4% to 5% sulfur with approximately 38% aromatics.
The Athabasca oil sands are bitumen-bearing sands, where the bitumen is isolated from the sand by a layer of water forming a water-wet tar sand. Water-wet tar sand is almost unique to the Athabasca oil sands and the water component is frequently termed connate water. Sometimes the term water-wet is used to describe this type of tar sand to distinguish it from the oil-wet sand deposits found more frequently in other tar sand formations and in shale deposits including those oily sands caused by oil spills.
The extraction of the bitumen from the sand and clay-like mineral material is generally accomplished by heating the composition with steam and hot water in a rotating vessel or drum and introducing an extraction agent or process aid. The process aid typically is sodium hydroxide NaOH and is introduced into the processing to improve the separation and recovery of bitumen particularly when dealing with difficult ores. The hot water process is carried out in a vessel called a separator cell or more specifically a primary separator vessel (PSV) after the oil sand has been conditioned in the rotating drum.
The PSV process produces a primary bitumen froth gathered in a launder from the upper perimeter of the vessel; a mineral tailings output from the lower portion of the vessel and a middlings component that is removed from the mid-portion of the vessel. It has been found that production of the middlings component varies with the fines and clay content of the originating oil sand and is described more fully, for example in Canadian patent 857,306 to Dobson. The middlings component contains an admixture of bitumen traces, water and mineral material in suspension. The middlings component is amenable to secondary separation of the bitumen it contains, by introducing air into the process flow in flotation cells. The introduced air causes the bitumen to be concentrated at the surface of the flotation cell. The flotation of the bitumen in preference to the solids components permits the air entrained bitumen to be extracted from the flotation cell. Flotation of the air-entrained bitumen from the process flow is sometimes termed differential flotation. The air-entrained bitumen froth is also referred to as secondary froth and is a mixture of the bitumen and air that rises to the surface of the flotation cell. Typically, the secondary froth may be further treated, for example by settling, and is recycled to the PSV for reprocessing.
Further treatment of the primary bitumen froth from the PSV requires removal of the mineral solids, the water and the air from the froth to concentrate the bitumen content. Conventionally, this is done by the use of centrifuges. Two types of centrifuge systems have heretofore been deployed. One, called a solids-bowl centrifuge has been used to reduce the solids in froth substantially. To remove water and solids from the froth produced by a solids-bowl centrifuge; a secondary centrifuge employing a disk has been used. Disk centrifuges are principally de-watering devices, but they help to remove mineral as well. Examples of centrifuge systems that have been deployed are described in Canadian patents 873,854; 882,667; 910,271 and 1,072,473 (U.S. Pat. No. 4,383,914). The Canadian patent 873,854 to Baillie for example, provides a two-stage solid bowl and disk centrifuge arrangement to obtain a secondary bitumen froth from the middlings stream of a primary separation vessel in the hot water bitumen recovery process. The Canadian patent 882,667 to Daly teaches diluting bitumen froth with a naphtha diluent and then processing the diluted bitumen using a centrifuge arrangement.
Centrifuge units require an on-going expense in terms of both capital and operating costs. Maintenance costs are generally high with centrifuges used to remove water and solid minerals from the bitumen froth. The costs are dictated by the centrifuges themselves, which are mechanical devices having moving parts that rotate at high speeds and have substantial momentum. Consequently, by their very nature, centrifuges require a lot of maintenance and are subject to a great deal of wear and tear. Therefore, elimination of centrifuges from the froth treatment process would eliminate the maintenance costs associated with this form of froth treatment. Additional operating cost results from the power cost required to generate the high g-forces in large slurry volumes.
In the past, cyclones of conventional design have been proposed for bitumen froth treatment, for example in Canadian patents 1,026,252 to Lupul and 2,088,227 (U.S. Pat. No. 5,316,664) to Gregoli. However, a basic problem is that recovery of bitumen always seems to be compromised by the competing requirements to reject water and solids to tailings while maintaining maximum hydrocarbon recovery. In practice, processes to remove solids and water from bitumen have been offset by the goal of maintaining maximal bitumen recovery. Cyclone designs heretofore proposed tend to allow too much water content to be conveyed to the overflow product stream yielding a poor bitumen-water separation. The arrangement of Lupul is an example of use of off-the-shelf cyclones that accomplish high bitumen recovery, unfortunately with low water rejection. The low water rejection precludes this configuration from being of use in a froth treatment process, as too much of the water in the feed stream is passed to the overflow or product stream.
A hydrocyclone arrangement is disclosed in Canadian patent 2,088,227 to Gregoli. Gregoli teaches alternative arrangements for cyclone treatment of non-diluted bitumen froth. The hydrocyclone arrangements taught by Gregoli attempt to replace the primary separation vessel of a conventional tar sand hot water bitumen processing plant with hydrocyclones. The process arrangement of Gregoli is intended to eliminate conventional primary separation vessels by supplanting them with a hydrocyclone configuration. This process requires an unconventional upgrader to process the large amounts of solids in the bitumen product produced by the apparatus of Gregoli. Gregoli teaches the use of chemical additive reagents to emulsify high bituminous slurries to retain water as the continuous phase of emulsion. This provides a low viscosity slurry to prevent the viscous plugging in the hydrocyclones that might otherwise occur. Without this emulsifier, the slurry can become oil-phase continuous, which will result in several orders of magnitude increase in viscosity. Unfortunately, these reagents are costly making the process economically unattractive.
Another arrangement is disclosed in Canadian patent 2,029,756 to Sury, which describes an apparatus having a central overflow conduit to separate extracted or recovered bitumen from a froth fluid flow. The apparatus of Sury is, in effect, a flotation cell separator in which a feed material rotates about a central discharge outlet that collects a launder overflow. The arrangement of Sury introduces process air to effect bitumen recovery and is unsuitable for use in a process to treat deaerated naphtha-diluted-bitumen froth as a consequence of explosion hazards present with naphtha diluents and air.
Other cyclone arrangements have been proposed for hydrocarbon process flow separation from gases, hot gases or solids and are disclosed for example in Canadian patents 1,318,273 (U.S. Pat No. 4,944,867) to Mundstock et al; 2,184,613 (U.S. Pat No. 5,538,696) to Raterman et al and in Canadian published patent applications 2,037,856 (U.S. Pat. No. 5,400,569); 2,058,221 (U.S. Pat. No. 5,183,558); 2,108,521 (U.S. Pat. No. 5,221,301); 2,180,686; 2,263,691 (U.S. Pat. No. 5,938,803); 2,365,008 (U.S. Pat. No. 6,846,463) and the hydrocyclone arrangements of Lavender et al in Canadian patent publications 2,358,805, 2,332,207 and 2,315,596.
SUMMARY OF THE INVENTION
In the following narrative wherever the term bitumen is used the term diluted bitumen is implied. This is because the first step of this froth treatment process is the addition of a solvent or diluent such as naphtha to reduce viscosity and to assist hydrocarbon recovery. The term hydrocarbon could also be used in place of the word bitumen for diluted bitumen.
The present invention provides a bitumen froth process circuit that uses an arrangement of hydrocarbon cyclones and inclined plate separators to perform removal of solids and water from the bitumen froth that has been diluted with a solvent such as naphtha. The process circuit has an inclined plate separator and hydrocarbon cyclone stages. A circuit configured in accordance with the invention provides a process to separate the bitumen from a hybrid emulsion phase in a bitumen froth. The hybrid emulsion phase includes free water and a water-in-oil emulsion and the circuit of the present invention removes minerals such as silica sand and other clay minerals entrained in the bitumen froth and provides the removed material at a tailings stream provided at a circuit tails outlet. The process of the invention operates without the need for centrifuge equipment. The elimination of centrifuge equipment through use of hydrocarbon cyclone and inclined plate separator equipment configured in accordance with the invention provides a cost saving in comparison to a process that uses centrifuges to effect bitumen de-watering and demineralization. However, the process of the invention can operate with centrifuge equipment to process inclined plate separator underflow streams if so desired.
The apparatus of the invention provides an inclined plate separator (IPS) which operates to separate a melange of water-continuous and oil-continuous emulsions into a cleaned oil product and underflow material that is primarily a water-continuous emulsion. The cyclone apparatus processes a primarily water-continuous emulsion and creates a product that constitutes a melange of water-continuous and oil-continuous emulsions separable by an IPS unit. When the apparatus of the invention is arranged with a second stage of cyclone to process the underflow of a first stage cyclone, another product stream, separable by an IPS unit can be created along with a cleaned tails stream.
In accordance with the invention, the bitumen froth to be treated is supplied to a circuit inlet for processing into a bitumen product provided at a circuit product outlet and material removed from the processed bitumen froth is provided at a circuit tails outlet. The bitumen froth is supplied to a primary inclined plate separator (IPS) stage, which outputs a bitumen enhanced overflow stream and a bitumen depleted underflow stream. The underflow output stream of the first inclined plate separator stage is a melange containing a variety of various emulsion components supplied as a feed stream to a cyclone stage. The cyclone stage outputs a bitumen enhanced overflow stream and a bitumen depleted underflow stream. The formation of a stubborn emulsion layer can block the downward flow of water and solids resulting in poor bitumen separation. These stubborn emulsion layers are referred to as rag-layers. The process of the present invention is resistant to rag-layer formation within the inclined plate separator stage, which is thought to be a result of the introduction of a recycle feed from the overflow stream of the hydrocarbon cyclone stage.
The material of the recycle feed is conditioned in passage through a hydrocarbon cyclone stage. When the recycle material is introduced into the inclined plate separator apparatus, a strong upward bitumen flow is present even with moderate splits. Static deaeration, that is removal of entrained air in the froth without the use of steam, is believed to be another factor that promotes enhanced bitumen-water separation within the inclined plate separators. A bitumen froth that has been deaerated without steam is believed to have increased free-water in the froth mixture relative to a steam deaerated froth, thus tending to promote a strong water flow in the underflow direction, possibly due to increased free-water in the new feed. In a process arranged in accordance with this invention distinct rag-layers are not manifested in the compression or underflow zones of the IPS stages.
The underflow output stream of the first inclined plate separator stage is supplied to a primary hydrocarbon cyclone stage, which transforms this complex mixture into an emulsion that is available from the primary cyclone stage as an overflow output stream. In a preferred arrangement, the overflow output stream of the primary cyclone stage is supplied to an IPS stage to process the emulsion. The overflow output stream of an IPS stage provides a bitumen product that has reduced the non-bitumen components in an effective manner.
The hydrocarbon cyclone apparatus of the present invention has a long-body extending between an inlet port and a cyclone apex outlet, to which the output underflow stream is directed, and an abbreviated vortex finder to which the output overflow stream is directed. This configuration permits the cyclone to reject water at a high percentage to the underflow stream output at the apex of the cyclone. This is accomplished in process conditions that achieve a high hydrocarbon recovery to the overflow stream, which is directed to the cyclone vortex finder, while still rejecting most of the water and minerals to the apex underflow stream. Mineral rejection is assisted by the hydrophilic nature of the mineral constituents. The cyclone has a shortened or abbreviated vortex finder, allowing bitumen to pass directly from the input bitumen stream of the cyclone inlet port to the cyclone vortex finder to which the output overflow stream is directed. The long-body configuration of the cyclone facilitates a high water rejection to the apex underflow. Thus, the normally contradictory goals of high hydrocarbon recovery and high rejection of other components are simultaneously achieved.
The general process flow of the invention is to supply the underflow of an inclined plate separator stage to a cyclone stage. To have commercial utility, it is preferable for the cyclone units to achieve water rejection. Water rejection is simply the recovery of water to the underflow or reject stream.
In addition to the unique features of the hydrocarbon cyclone apparatus the process units of this invention interact with each other in a novel arrangement to facilitate a high degree of constituent material separation to be achieved. The bitumen froth of the process stream emerging as the cyclone overflow is conditioned in passage through the cyclone to yield over 90% bitumen recovery when the process stream is recycled to the primary inclined plate separator stage for further separation. Remarkably, the resultant water rejection on a second pass through the primary cyclone stage is improved over the first pass. These process factors combine to yield exceptional bitumen recoveries in a circuit providing an alternate staging of an inclined plate separator stage and a cyclone stage where the bitumen content of the output bitumen stream from the circuit exceeds 98.5% of the input bitumen content. Moreover, the output bitumen stream provided at the circuit product outlet has a composition suitable for upgrader processing.
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
FIG. 1 is a schematic diagram depicting a preferred arrangement of apparatus adapted to carry out the process of the invention.
FIG. 2 is an elevation cross-section view of a preferred embodiment of a cyclone.
FIG. 3 is a top cross-section view of the cyclone of FIG. 2 . FIG. 3 a is an enlarged cross-section view of a portion of an operating cyclone.
FIG. 4 is a schematic diagram depicting another preferred arrangement of apparatus adapted to carry out the process of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 is a schematic diagram depicting the arrangement of apparatus adapted to carry out the process of the invention. The schematic diagram provides an outline of the equipment and the process flows, but does not include details, such as pumps, that provide the ability to transport the process fluids from one unit to the next. The apparatus of the invention includes inclined plate separator (IPS) stage units and cyclone stage units, each of which process an input stream to produce an overflow output stream, and an underflow output stream. The IPS overflow output stream has a bitumen enriched content resulting from a corresponding decrease in solids, fines and water content relative to the bitumen content of the IPS input stream. The IPS underflow output stream has solids, fines and water with a depleted bitumen content relative to the IPS input stream. The IPS underflow output stream may be referred to as a bitumen depleted stream. The cyclone stage overflow output stream has a bitumen enriched content resulting from a corresponding decrease in solids, fines and water content relative to the bitumen content of the cyclone input stream. The cyclone underflow output stream has solids, fines and water with a depleted bitumen content relative to the cyclone input stream. The cyclone underflow output stream may be referred to as a bitumen depleted stream.
While the process flows and apparatus description of the invention made with reference to FIG. 1 refers to singular units, such as a cyclone 16 or 28 , a plurality of cyclone units are used in each stage where process scale requires. For example, for production rates in excess of 200,000 bbl/day of bitumen, cyclone units are arranged in parallel groups of 30 or more with each cyclone unit bearing about 200 gal/min of flow. In the general arrangement of the apparatus adapted to carry out the process, inclined plate separator (IPS) units are alternately staged with cyclone units such that an IPS stage underflow feeds a cyclone stage, while a cyclone stage overflow feeds an IPS stage. The mutual conditioning of each stage contributes to the remarkable constituent separation performance obtained by the unit staging of this process.
The processing circuit has a circuit inlet 10 to receive a process feed stream 48 . The process feed stream is a bitumen froth output of an oil sands extraction process and is diluted at 11 with a suitable solvent, for example naphtha, or a paraffinic or alkane hydrocarbon solvent. Naphtha is a mixture of aromatic hydrocarbons that effectively dissolves the bitumen constituent of the bitumen froth feed stream 48 supplied via line 10 to produce bitumen froth with a much-reduced viscosity. The addition of a solvent partially liberates the bitumen from the other components of the bitumen froth feed stream 48 by reducing interfacial tensions and rendering the composition more or less miscible. The diluted bitumen feed stream 50 including a recycle stream 57 is supplied to a primary IPS stage comprising IPS units 12 and 14 shown as an example of multiple units in a process stage. The overflow output stream 52 of the primary IPS stage is supplied as a product stream, which is sent to the circuit product outlet line 42 for downstream processing, for example at an upgrader plant.
The underflow output stream of the primary IPS stage is supplied via line 30 as the feed stream 68 to a primary hydrocarbon cyclone stage (HCS) comprising for example, a primary cyclone 16 . The hydrocarbon cyclone processes a feed stream into a bitumen enriched overflow stream and a bitumen depleted underflow stream. The overflow output stream 56 of the primary cyclone stage on line 18 is directed for further processing depending on the setting of diverter valve 34 . Diverter valve 34 is adjustable to direct all or a portion of the primary HCS overflow output stream 56 to a recycle stream 60 that is carried on line 24 to become recycle stream 57 or a part of it. Recycle stream 57 is supplied to the primary IPS stage. The portion of the primary HCS overflow output stream that is not directed to recycle stream 60 becomes the secondary IPS feed stream 58 that is delivered to a secondary IPS stage 22 via line 20 . Naturally diverter valve 34 can be set to divert the entire HCS overflow stream 56 to the secondary IPS feed stream 58 to the limit of the secondary IPS capacity.
The circuit bitumen froth feed stream 48 will have varying quantities or ratios of constituent components of bitumen, solids, fines and water. The quantities or ratios of the component of froth feed stream 48 will vary over the course of operation of the circuit depending on the composition of the in situ oil sands ore that are from time to time being mined and processed. Adjustment of diversion valve 34 permits the processing circuit flows to be adjusted to accommodate variations in oil sands ore composition, which is reflected in the composition of the bitumen froth feed stream 48 . In this manner, the circuit process feed flow 50 to the primary cyclone stage can be set to adapt to the processing requirements providing optimal processing for the composition of the bitumen froth feed. In some circumstances, such as when the capacity of the secondary IPS stage 22 is exceeded, all or a portion of the primary cyclone stage overflow stream 56 on line 18 is directed to recycle stream 60 by diverter valve 34 . Recycle stream 60 is carried on line 24 to form part of the recycle stream 57 supplied to the primary IPS stage IPS units 12 and 14 . However, the composition of stream 48 is nearly invariant to the composition of mine run ore over a wide range of ores that might be fed to the upstream extraction process.
The preferred embodiment of a process circuit in accordance with the principles of the invention preferably includes secondary IPS processing equipment interconnecting with the primary processing equipment by means of diverter valve 34 . Where the entire overflow output stream of the primary stage is recycled back to the primary IPS stage, the primary IPS stage process acts as a secondary IPS stage and no stream is supplied to the secondary IPS stage for processing. However, a secondary IPS stage is preferably provided to accommodate the variations in composition of the feed froth stream 48 encountered in operation of the process. Secondary IPS unit 22 processes the feed stream 58 received from the overflow of the primary cyclone stage into a bitumen enriched secondary IPS overflow output stream on line 32 and a bitumen depleted secondary IPS underflow output stream 59 on line 26 . The recovered bitumen of the secondary IPS overflow stream on line 32 is combined with the overflow stream of the primary IPS stage to provide the circuit output bitumen product stream 52 delivered to the circuit product outlet line 42 for downstream processing and upgrading.
The secondary stage IPS 22 underflow output stream 59 is supplied by line 26 where it is combined with the primary cyclone underflow stream 61 to provide a feed stream 62 to a secondary stage cyclone 28 . The secondary hydrocarbon cyclone stage (HCS) 28 processes input feed stream 62 into a bitumen enriched secondary HCS overflow output stream 64 on line 40 and a bitumen depleted secondary HCS underflow output stream 66 on line 36 . The secondary HCS underflow output stream 66 is directed to a solvent recovery unit 44 , which processes the stream to produce the circuit tailings stream 54 provided to the circuit tails outlet 46 of the circuit. The operating process of the secondary HCS 28 is varied during the operation of the process. The operating process of the secondary HCS 28 is optimized to reduce the bitumen content of the secondary HCS underflow output stream 66 to achieve the target bitumen recovery rate of the process. Preferably, the operation of the secondary HCS is maintained to achieve a hydrocarbon content in the secondary HCS underflow output stream 66 that does not exceed 1.6%. Preferably, a solvent recovery unit 44 is provided to recover diluent present in the secondary HCS underflow output stream 66 . Solvent recovery unit (SRU) 44 is operated to maintain solvent loss to the tailings stream 54 below 0.5% to 0.7% of the total solvent fed to the circuit on line 11 . The tailings stream 54 is sent for disposal on the circuit tails outlet line 46 .
The primary and secondary HCS cyclone units achieve a so-called ternary split in which a high hydrocarbon recovery to the output overflow stream is obtained with a high rejection of solids and water reporting to the output underflow stream. In a ternary split, even the fines of the solids are rejected to a respectable extent.
The primary HCS cyclone unit 16 receives the underflow output stream on line 30 from the primary IPS stage IPS units 12 , 14 as an input feed stream 68 . The primary hydrocarbon cyclone 16 processes feed stream 68 to obtain what is referred to herein as a ternary split. The hydrocarbon and other constituents of the cyclone feed stream are reconstituted by the hydrocarbon cyclone 16 so as to enable the primary HCS overflow output stream on line 18 to be supplied, via line 20 , as a feed stream 58 to a secondary IPS stage unit 22 . This process flow obtains a ternary split, which achieves a high bitumen recovery. The process within primary HCS cyclone unit 16 involves a complex transformation or re-conditioning of the received primary IPS underflow output stream 68 . The primary HCS underflow output stream 61 is passed via line 38 to become part of the feed stream 62 of secondary HCS cyclone unit 28 and yield further bitumen recovery. Further bitumen recovery from the secondary HCS overflow output stream 64 is obtained by recycling that stream on line 40 back to the primary IPS stage for processing.
The closed loop nature of the recycling of this process reveals an inner recycling loop, which is closed through line 26 from the secondary IPS stage and an outer recycling loop, which is closed through line 40 from the secondary HCS. These recycle loops provide a recycle stream 57 which contains material from the primary and secondary HCS and the bitumen recovered from this recycle material is called second-pass bitumen. Remarkably the second-pass bitumen in recycle stream 57 is recovered in the primary IPS stage at greater than 90% even though the bitumen did not go to product in the first pass through the primary IPS stage. Thus, the arrangement provides a cyclic process in which the overflow stream of a HCS is reconditioned by an IPS stage and the underflow stream of an IPS stage is reconditioned by a HCS. In this way, the individual process stages recondition their overflow streams in the case of cyclone stages and their underflow streams in the case of IPS stages for optimal processing by other downstream stages in the process loops. In the HCS cyclone units, the flow rates and pressure drops can be varied during operation of the circuit. The HCS unit flow rates and pressure drops are maintained at a level to achieve the performance stated in Tables 1 and 2. An input stream of a cyclone is split to the overflow output stream and the underflow output stream and the operating flow rates and pressure drops will determine the split of the input stream to the output streams. Generally, the range of output overflow split will vary between about 50% to about 80% of the input stream by varying the operating flow rates and pressure drops.
Table 1 provides example compositions of various process streams in the closed-loop operation of the circuit.
TABLE 1
Min-
Wa-
Sol-
Hydro-
Stream
Bitumen
eral
ter
vent
Coarse
Fines
carbon
48 New feed
55.00
8.50
36.50
00.00
3.38
5.12
55.00
50 IPS feed
34.95
5.95
41.57
17.52
2.17
3.78
52.48
52 Product
63.51
0.57
2.06
33.86
0.00
0.57
97.37
54 Tails
1.02
17.59
80.98
0.59
7.42
10.17
1.61
Table 2 lists process measurements taken during performance of process units arranged in accordance with the invention. In the table, the Bitumen column is a hydrocarbon with zero solvent. Accordingly, the Hydrocarbon column is the sum of both the Bitumen and Solvent columns. The Mineral column is the sum of the Coarse and the Fines columns. These data are taken from a coherent mass balance of operational data collected during demonstration and operational trials. From these trials it was noted that water rejection on the HCS is over 50%. It was also noted that the nominal recovery of EPS stage is about 78%, but was boosted to over 85% by the recycle. All of the stages in the circuit operate in combination to produce a recovery of bitumen approaching 99% and the solvent losses to tails are of the order of 0.3%.
TABLE 2
Unit Operations Performance of Hydrocarbon Cyclones
and Inclined Plate Separators in Closed Loop
Unit
Unit
Unit
Hydrocarbon
Water
Solids
Unit Process
Recovery
Rejection
Rejection
Fines Rejection
Primary IPS
78%
98%
97%
Primary
85%
55%
78%
Cyclone
Secondary
85%
54%
82%
Cyclone
Recycle or
91%
98.5%
95.5%
Secondary IPS
Overall
99.2% Bitumen
Recovery
99.7% Solvent
Product Spec
2.0% H2O
0.57% Mineral
0.32% non-
bituminous
hydrocarbon
(NBHC)
FIG. 2 shows an elevation cross-section of a preferred embodiment of the hydrocarbon cyclone apparatus depicting the internal configuration of the cyclone units. The cyclone 70 defines an elongated conical inner surface 72 extending from an upper inlet region 74 to an outlet underflow outlet 76 of lower apex 88 . The cyclone has an upper inlet region 74 with an inner diameter DC and an upper overflow outlet 84 of a diameter DO at the vortex finder 82 and an underflow outlet 76 at the lower apex, which has a diameter DU. The effective underflow outlet diameter 76 at the lower apex 88 of the cyclone is also referred to as a vena cava. It is somewhat less than the apex diameter due to the formation of an up-vortex having a fluid diameter called the vena cava. The fluid flows near the lower apex 88 of a cyclone are shown in FIG. 3 a . The cyclone has a free vortex height FVH extending from the lower end 92 of the vortex finder to the vena cava of the lower apex 88 . The fluid to be treated is supplied to the cyclone via input channel 78 that has an initial input diameter DI. The input channel 78 does not need to have a uniform cross-section along its entire length from the input coupling to the cyclone inlet 80 . The fluid to be treated is supplied under pressure to obtain a target velocity within the cyclone when the fluid enters the cyclone through cyclone inlet 80 . Force of gravity and the velocity pressure of the vortex urge the fluid composition entering the cyclone inlet downward toward apex 76 . An underflow fluid stream is expelled through the lower apex 76 . The underflow stream output from the cyclone follows a generally helical descent through the cyclone cavity. The rate of supply of the fluid to be treated to the cyclone 70 causes the fluid to rotate counter-clockwise (in the northern hemisphere) within the cyclone as it progresses from the upper inlet region 74 toward the underflow exit of lower apex 76 . Variations in density of the constituent components of the fluid composition cause the lighter component materials, primarily the bitumen component, to be directed toward vortex finder 82 in the direction of arrow 86 .
As depicted in FIG. 3 a , when the cyclone is operating properly the fluid exits the apex of they cyclone as a forced spray 89 with a central vapour core 97 extending along the axis of the cyclone. Near the apex 76 a central zone subtended by the vena cava 91 is formed. The vena cava is the point of reflection or transformation of the descending helix 93 into an ascending helix 95 . Contained within this hydraulic structure will be an air core or vapour core 97 supported by the helical up and down vortices. This structure is stable above certain operating conditions, below which the flow is said to rope. Under roping conditions the air core and the up-vortex will collapse into a tube of fluid that will exit downward with a twisting motion. Under these circumstances the vortex flow will cut off and there will be zero separation. Roping occurs when the solids content of the underflow slurry becomes intolerably high.
The vortex finder 82 has a shortened excursion where the vortex finder lower end 92 extends only a small distance below cyclone inlet 80 . A shortened vortex finder allows a portion of the bitumen in the inlet stream to exit to the overflow output passage 84 without having to make a spiral journey down into the cyclone chamber 98 and back up to exit to the overflow output passage 84 . However, some bitumen in the fluid introduced into the cyclone for processing does make this entire journey through the cyclone chamber to exit to the overflow output passage 84 . The free vortex height FVH, measured from the lower end of the vortex finder 92 to the underflow outlet 76 of lower apex 88 , is long relative to the cyclone diameters DI and DO. Preferably, a mounting plate 94 is provided to mount the cyclone, for example, to a frame structure (not shown).
Preferably the lower portion 88 of the cyclone is removably affixed to the body of the cyclone by suitable fasteners 90 , such as bolts, to permit the lower portion 88 of the cyclone to be replaced. Fluid velocities obtained in operation of the cyclone, cause mineral materials that are entrained in the fluid directed toward the lower apex underflow outlet 76 to be abrasive. A removable lower apex 88 portion permits a high-wear portion of the cyclone to be replaced as needed for operation of the cyclones. The assembly or packaging of the so-called cyclopac has been designed to facilitate on-line replacement of individual apex units for maintenance and insertion of new abrasion resistant liners.
FIG. 3 shows a top view cross-section of the cyclone of FIG. 2 . The cyclone has an injection path 96 that extends from the input channel 78 to the cyclone inlet 80 . Various geometries of injection path can be used, including a path following a straight line or a path following a curved line. A path following a straight line having an opening into the body of the cyclone that is tangential to the cyclone is called a Lupul Ross cyclone. In the preferred embodiment, the injection path 96 follows a curved line that has an involute geometry. An involute injection path assists in directing the fluid supplied to the cyclone to begin to move in a circular direction in preparation for delivery of the fluid through cyclone inlet 80 into the chamber 98 of the cyclone for processing. The counter-clockwise design is for use in the northern hemisphere in order to be in synch with the westerly coriolis force. In the southern hemisphere this direction would be reversed.
In the preferred embodiment of the cyclone, the dimensions listed in Table 3 are found:
TABLE 3
Path
DI
DC
DO
DU
FVH
ABRV
Primary Cyclone
Involute
50 mm
200 mm
50 mm
40 mm
1821 mm
102 mm
Secondary Cyclone
Involute
50 mm
150 mm
50 mm
50 mm
1133 mm
105 mm
Lupul Ross
Tangent
9.25 mm
64 mm
19 mm
6.4 mm
181 mm
32 mm
Cyclone
Where:
Path is the injection path length geometry. If the path is an involute, the body diameter DC is a parameter of the involute equation that defines the path of entry into the cyclone
DI is the inlet diameter at the entry of the fluid flow to the cyclone
DC is the body diameter of the cyclone in the region of entry into the cyclone
DO is the overflow exit path vortex finder diameter or the outlet pipe diameter
DU is the underflow exit path apex diameter at the bottom of the cyclone, also called the vena cava
FVH is the free vortex height or the distance from the lower end of the vortex finder to the vena cava
ABRV is the distance from the centre-line of the inlet flow path to the tip of the vortex finder. The shorter this distance the more abbreviated is the vortex finder.
The cyclones are dimensioned to obtain sufficient vorticity in the down vortex so as to cause a vapor core 97 in the centre of the up-vortex subtended by the vena cava. The effect of this vapor core is to drive the solvent preferentially to the product stream, provided to the overflow output port 84 , thereby assuring minimum solvent deportment to tails or underflow stream, provided to the underflow outlet 76 of lower apex. This is a factor contributing to higher solvent recovery in the process circuit. At nominal solvent ratios the vapor core is typically only millimeters in diameter, but this is sufficient to cause 3% to 4% enrichment in the overhead solvent to bitumen ratio.
A workable cyclone for use in processing a diluted bitumen froth composition has a minimum an apex diameter of 40 mm to avoid plugging or an intolerably high fluid vorticity. An apex diameter below 40 mm would result in high fluid tangential velocity yielding poor life expectancy of the apex due to abrasion even with the most abrasion resistant material. Consequently, a Lupul Ross cyclone design is undesirable because of the small size of openings employed.
The embodiments of the primary and secondary cyclones of the dimensions stated in Table 1 sustain a small vapour core at flow rates of 180 gallon/min or more. This causes enrichment in the solvent content of the overflow that is beneficial to obtaining a high solvent recovery. The vapour core also balances the pressure drops between the two exit paths of the cyclone. The long body length of these cyclones fosters this air core formation and assists by delivering high gravity forces within the device in a manner not unlike that found in centrifuges, but without the moving parts. In the preferred embodiment of the primary cyclone, the upper inlet region has an inner diameter of 200 mm. The injection path is an involute of a circle, as shown in FIG. 3 . In one and one half revolutions prompt bitumen can move into the vortex finder and exit to the overflow output passage 84 if the solvent to bitumen ratio is properly adjusted. The internal dimensions of the secondary cyclones are similar and the same principles apply as were stated in relation to the primary cyclones. However, the diameter of the body of the secondary cyclone is 150 mm to create a higher centrifugal force and a more prominent vapour core. The dimensions of the secondary cyclone are aimed at producing minimum hydrocarbon loss to tails. This is accomplished with as low as 15% hydrocarbon loss, which still allows for a water rejection greater than 50%.
The IPS units 12 , 14 and 22 of the IPS stages are available from manufacturers such as the Model SRC slant rib coalescing oil water separator line of IPS equipment manufactured by Parkson Industrial Equipment Company of Florida, U.S.A.
FIG. 4 is a schematic diagram depicting another preferred arrangement of apparatus adapted to carry out the process of the invention. As with FIG. 1 , the schematic diagram provides an outline of the equipment and the process flows, but does not include details, such as pumps that provide the ability to transport the process fluids from one unit to the next. The apparatus of the invention includes inclined plate separator (IPS) stage units and cyclone stage units and centrifuge stage units, each of which process an input stream to produce an overflow output stream, and an underflow output stream. The centrifuge overflow output stream has a bitumen enriched content resulting from a corresponding decrease in solids, fines and water content relative to the bitumen content of the centrifuge input stream. The centrifuge underflow output stream has solids, fines and water with a depleted bitumen content relative to the centrifuge input stream. The centrifuge underflow output stream may be referred to as a bitumen depleted stream.
In the general arrangement of the apparatus adapted to carry out the process, inclined plate separator (IPS) units are alternately staged with either cyclone units or centrifuge units such that an IPS stage underflow feeds a cyclone stage or a centrifuge stage or both a cyclone stage and a centrifuge stage. In addition a cyclone stage overflow or a centrifuge stage overflow is sent to product or feeds an IPS stage. This circuit enables one to take full advantage of centrifuges that might be destined for replacement. In another sense it provides a fallback to the circuit depicted in FIG. 1 .
In FIG. 4 , the same reference numerals are used to depict like features of the invention. The processing circuit has a circuit inlet 10 to receive a process feed stream 48 . The process feed stream is a deaerated bitumen froth output of an oil sands extraction process and is diluted at 11 with a suitable solvent, for example naphtha, or a paraffinic or alkane hydrocarbon solvent. The diluted bitumen feed stream 50 including a recycle streams 60 and 64 is supplied to a primary IPS stage comprising IPS units 12 and 14 shown as an example of multiple units in a process stage. The overflow output stream 52 of the primary IPS stage is supplied as a product stream, which is sent to the circuit product outlet line 42 for downstream processing, for example at an upgrader plant.
The underflow output stream of the primary IPS stage is supplied via line 30 as the feed stream 68 to a primary hydrocarbon cyclonestage (HCS) comprising for example, a primary cyclone 16 . The hydrocarbon cyclone processes a feed stream into a bitumen enriched overflow stream and a bitumen depleted underflow stream. The overflow output stream 56 of the primary cyclone stage on line 18 is directed for further processing depending on the setting of diverter valve 34 . Diverter valve 34 is adjustable to direct all or a portion of the primary HCS overflow output stream 56 to a recycle stream 60 that is carried on line 3 to become a recycle input to the feed stream 50 supplied to the primary IPS stage. The portion of the primary HCS overflow output stream that is not directed to recycle stream 60 can become all or a portion of either the secondary IPS feed stream 58 that is delivered to a secondary IPS stage 22 via line 2 or a centrifuge stage feed stream 100 that is delivered to a centrifuge stage 102 via line 1 . Naturally diverter valve 34 can be set to divert all of the HCS overflow stream 56 either to the secondary IPS feed stream 58 or to the centrifuge stage 102 .
When paraffinic solvents are deployed asphaltene production will occur. Under these circumstances the first stage cyclone underflow stream 61 can be configured separate from the second stage cyclones to provide two separate tailings paths for asphaltenes. On the other hand, asphaltene production is very low when naphtha based solvents are deployed in this process and, consequently, two separate tailings paths are not required.
Adjustment of diversion valve 34 permits the processing circuit flows to be adjusted to accommodate variations in oil sands ore composition, which is reflected in the composition of the bitumen froth feed stream 48 . In this manner, the circuit process feed flow 50 to the primary cyclone stage can be set to adapt to the processing requirements providing optimal processing for the composition of the bitumen froth feed. In some circumstances, such as when the capacity of the secondary IPS stage 22 and centrifuge stage 102 is exceeded, all or a portion of the primary cyclone stage overflow stream 56 on line 18 is directed to recycle stream 60 by diverter valve 34 .
The preferred embodiment of a process circuit in accordance with the principles of the invention preferably includes secondary IPS processing equipment or centrifuge processing equipment interconnecting with the primary stage processing equipment by means of diverter valve 34 . Where the entire overflow output stream of the primary stage is recycled back to the primary IPS stage, the primary IPS stage process acts as a secondary IPS stage and no stream is supplied to the secondary IPS stage or the centrifuge stage for processing. However, a secondary IPS stage or centrifuge stage or both is preferably provided to accommodate the variations in composition of the feed froth stream 48 encountered in operation of the process. Secondary IPS unit 22 processes the feed stream 58 received from the overflow of the primary cyclone stage into a bitumen enriched secondary IPS overflow output stream on line 32 and a bitumen depleted secondary IPS underflow output stream 59 on line 26 . The recovered bitumen of the secondary IPS overflow stream on line 32 is combined with the overflow stream of the primary IPS stage to provide the circuit output bitumen product stream 52 delivered to the circuit product outlet line 42 for downstream processing and upgrading. The centrifuge stage unit 102 processes the feed stream 100 received from the overflow of the primary cyclone stage into a bitumen enriched centrifuge output stream on line 104 and a bitumen depleted centrifuge underflow output stream 106 on line 108 . The recovered bitumen of the centrifuge overflow stream on line 104 is supplied to the circuit output bitumen product stream 52 , which is delivered to the circuit product outlet line 42 for downstream processing and upgrading.
The secondary stage IPS 22 underflow output stream 59 is processed in this embodiment in the same manner as in the embodiment depicted in FIG. 1 . The secondary HCS underflow output stream and the centrifuge output stream 106 are combined to form stream 66 , which is directed to a solvent recovery unit 44 . The solvent recovery unit 44 processes stream 66 to produce a circuit tailings stream 54 that is provided to the circuit tails outlet 46 of the circuit. The solvent recovery unit (SRU) 44 is operated to maintain solvent loss to the tailings stream 54 between 0.5% to 0.7% of the total solvent fed to the circuit at 11 . The tailings stream 54 is sent for disposal on the circuit tails outlet line 46 .
The closed loop nature of the recycling of this process reveals two recycling loops. One recycling loop is closed through line 3 from the primary IPS stage and primary HCS. Another recycling loop is closed from line 2 through the secondary IPS stage via line 26 and through the secondary HCS 28 via stream 64 . The feed to the disk centrifuges on line 1 does not provide a recycle loop; thus material sent to the disk centrifuge stage is not recycled back to the primary IPS stage. The HCS unit flow rates and pressure drops are maintained at a level that achieves the performance stated in Tables 1 and 2. An input stream of a cyclone is split to the overflow output stream and the underflow output stream and the operating flow rates and pressure drops will determine the split of the input stream to the output streams. Generally, the range of output overflow split will vary between about 50% to about 80% of the input stream by varying the operating flow rates and pressure drops.
Although a preferred and other possible embodiments of the invention have been described in detail and shown in the accompanying drawings, it is to be understood that the invention in not limited to these specific embodiments as various changes, modifications and substitutions may be made without departing from the spirit, scope and purpose of the invention as defined in the claims appended hereto. | Discloses apparatus to perform a process to remove water and minerals from a bitumen froth output of a oil sands hot water extraction process. A bitumen froth feed stream is diluted with a solvent and supplied to a primary inclined plate separator stage, which separates the bitumen into an overflow stream providing a bitumen product output from the circuit and a bitumen depleted underflow stream. A primary cyclone state, a secondary inclined plate separator stage and a secondary cyclone stage further process the underflow stream to produce a secondary bitumen recovery product stream and a recycle stream. The secondary bitumen recovery product stream is incorporated into and becomes part of the circuit bitumen product output stream. The recycle stream is incorporated into the bitumen froth feed stream for reprocessing by the circuit. | 1 |
This is a continuation of application Ser. No. 06/599,280, filed Apr. 11, 1984 abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention generally relates to a catalytic converter for use with an internal combustion engine to purify exhaust gas emanating therefrom and, more particularly, to a monolithic catalytic converter of the type which uses a honeycomb catalyst carrier.
2. Description of the Prior Art
In a catalytic converter of the type described, a catalyst carrier is housed in a retainer member which is formed of a stainless steel mesh, or in a foamed mat, such as ceramic wool available in the trade name INTERAM MAT from 3M Co. Ltd., U.S.A. The catalyst carrier is put in a generally cylindrical split casing which consists of two casing halves, together with seal members for sealing opposite ends of the casing. The abutting faces of the casing halves are welded or otherwise joined to each other. For details of such a catalytic converter, a reference may be made to Japanese Patent Laid-Open Publication Nos. 212319/1982 and 2412/1983.
Meanwhile, a honeycomb catalyst carrier employed with such a catalytic converter comprises a sintered integral body mainly consisting of SiO 2 , Al 2 O 3 and MgO and, therefore, it lacks resistivity against shocks and impacts. In addition to the fragility, the dimensional accuracy of finished honeycomb catalyst carriers is quite rough. For example, where catalyst carriers each having a circular cross-section are produced with a designed diameter of 65 millimeters, the scattering or expected diameter deviation in the actual diameters of the products amounts to a little over 2 millimeters; where catalyst carriers each having an oval cross-section are produced with a designed shorter diameter of 65 millimeters and a longer diameter of 130 millimeters, the scatterings or expected diameter deviations in the two diameters individually amount to a little over 4 millimeters.
Assume a case wherein a catalyst carrier of the type discussed is loaded in the prior art split casing in which the casing halves are clamped together with a predetermined margin at abutting ends thereof. Then, if the catalyst carrier is relatively large-size, the clamping load will be excessive and damage the catalyst carrier while, if the catalyst carrier is relatively small-size, the clamping load will be short and only loosely retain the catalyst carrier to enhance the liability to damage, due to the severe scatterings situation discussed above. The excessive or short clamping load, therefore, is incapable of allowing the prior art catalytic converter to fully exhibit its expected function. While this problem may be solved by increasing or decreasing the number of the retainer members and/or that of the seal members after actually measuring the dimensions of each catalyst carrier such that a predetermined clamping load acts adequately on all the catalyst carriers, such an implementation will increase the number of assembling steps to a degree which is objectionable for quantity production.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide a new and improved catalytic converter for an internal combustion engine which eliminates the drawbacks inherent in the prior art catalytic converter for an internal combustion engine as stated above.
It is another object of the present invention to provide a catalytic converter for an internal combustion engine which is feasible for quantity production.
It is still another object of the present invention to provide a catalytic converter for an internal combustion engine which is stable in quality and desirable in durability.
According to the invention there is provided an insulated, muffled, straight-line flow catalytic converter which is formed under a constant load for high quantity production, consisting essentially of:
a generally cylindrical catalyst carrier having an approximate dimension of length and an approximate dimension of diameter which may be less than, greater than or equal to a desired diameter and which falls within an expected diameter deviation, and having a longitudinal central axis;
a circumferential retainer member resiliently surrounding substantially the given length of said catalyst carrier;
a first generally hemicylindrical casing half extending through approximately 180° about said central axis and terminating in a pair of longitudinal ends each having a radially extending annular end flange, said casing half being longer than the length of said carrier and terminating at the side edges thereof in a pair of longitudinally extending end faces, said casing half having on each side thereof as longitudinal flange extending substantially the length of said casing half, each longitudinal flange including a generally planar coupling wall portion having said longitudinally extending end face;
a second generally hemicylindrical casing half extending through approximately 180° about said central axis and terminating in a pair of longitudinal ends each having a radially extending annular end flange; said second casing half being longer than the length of the carrier and terminating at the side edges thereof in a pair of longitudinally extending end faces, said second casing half having a radially outwardly extending longitudinal flange extending longitudinally substantially the length of said second casing half and having an inner face and each longitudinal flange terminating in a generally perpendicular flange including a generally planar coupling wall portion extending generally perpendicular to and substantially the length of said longitudinal flange and extending a tangential distance sufficient to overlap the adjacent coupling wall portion with a clamping margin between each end face of said coupling wall portion of said first casing half and said inner face of said longitudinal flange of said second casing half defining a spacing which allows for different diameter catalyst carriers to be mounted within said first and second casing halves;
said first casing half and said second casing half being adapted to retain and circumferentially surround said carrier and said retainer member when a predetermined load is applied with said adjacent coupling wall portions being in mating and overlapping relationship and with the distance of overlap being greater than said clamping margin but sufficient to retain said carrier in a fixed position within the cylindrical casing having said annular end flanges and being formed by said mated casing halves regardless of the expected diameter deviation of the diameter of the catalyst carrier received in said casing and with said adjacent coupling wall portions having a sufficient amount of overlap to accommodate catalyst carriers of different diameters;
first and second short cylindrical tubes, each having the same diameter which is greater than a diameter of said, annular end flanges of said generally cylindrical casing and each having a radially inwardly extending flange surrounding an orifice which is in a plane perpendicular to said central axis, each short tube being individually affixed along an inner periphery of an outwardly facing surface of said flange of said tube to an adjacent outwardly facing surface of one of said annular end flanges of said generally cylindrical casing; and
an elongate outer tube extending circumferentially about said central axis, said first and second short tubes having said cylindrical casing joined thereto between said first and second short tubes, and being received within said outer tube t form a heat insulating chamber between said cylindrical casing and said outer tube, said outer tube extending longitudinally beyond said short tubes to form at least two muffling chambers, one between said first short tube and a first end of said outer tube and another between said second short tube and a second end of said outer tube.
BRIEF DESCRIPTION OF THE DRAWINGS
The objects and features of the present invention will become more apparent from a consideration of the following detailed description taken in conjunction with the accompanying drawings in which:
FIG. 1 is a perspective view showing an exhaust system of an internal combustion engine which is equipped with a catalytic converter;
FIG. 2 is a side elevational view of a catalytic converter for an internal combustion engine in accordance with the present invention with portions broken away;
FIG. 3 is a cross-section view taken along line III--III of FIG. 2;
FIG. 4 and 5 are cross-sectional views showing modifications to the catalytic converter shown in FIGS. 2 and 3;
FIG. 6 is a cross-sectional view of another embodiment of the present invention;
FIG. 7 is a cross-sectional view taken along line VII--VII of FIG. 6; and
FIG. 8 is a fragmentary sectional view showing a modification to the catalytic converter shown in FIGS. 6 and 7.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 1 of the drawings, an exhaust system 10 of an internal combustion engine is shown and includes a generally cylindrical catalytic converter 12 in accordance with the present invention. The catalytic converter 12 is shown in a partly taken-away sectional side elevation in FIG. 2. As shown, the catalytic converter 12 comprises casing halves 14 and 16 which are divided from each other in the lengthwise direction of the catalytic converter 12. The catalytic converter 12 includes a body portion 20 having a generally cylindrical wall. The body portion 20 is tapered at opposite ends thereof to terminate at a pair of connecting portions 18, which are individually fit on the engine exhaust system 10. Each of the connecting portions 18 is smaller in diameter than the body portion 20. The tapered portions intervening between the body portion 20 and the opposite connecting portions 18 are designated by the reference numeral 22. p As shown in FIG. 3, the casing half 14 is formed with flanges 24 along the length thereof, and the casing half 16 with flanges 26 along the length thereof. Each of the flanges 24 comprises a bent wall portion 28 extending from the cylindrical wall of the body portion 20 of the casing half 14, and a coupling wall portion 30 extending from and perpendicular to the bent wall portion 28. That is, the coupling wall portions 30 of the flanges 24 extend over a predetermined length and are parallel to each other in a direction indicated by an arrow A which is perpendicular to the lengthwise direction of the body portion 20. Meanwhile, the flanges 26 comprise coupling wall portions 32 which extend over a predetermined length from the cylindrical wall of the body 20 parallel to each other and in a direction indicated by an arrow B, which is perpendicular to the lengthwise direction of the body portion 20. The casing halves 14 and 16 are assembled together with the inner surfaces of the coupling wall portions 30 of the flanges 24 respectively engaged with the outer surfaces of the coupling wall portions 32 of the flanges 26. The reference character d in the drawing indicates a spacing, or clamping margin, defined between an inner face 34 of each bent wall portion 28 of the flange 24 and an end face 36 of the adjacent coupling wall portion 32 of the flange 26 when the casing halves 14 and 16 are put together each flange 24 extends tangentially to a circumferential, longitudinally extending, side end face 37.
In assembly, a honeycomb catalyst carrier 40 which is housed in a retainer member 38 is put into the body portions 20 of the casing halves 14 and 16. The retainer member 38 may be made of thermo-foaming resin, for example. Then, wire nets or like seal members 42 (see FIG. 2) are placed in the body portion 20 adjacent to the opposite tapered portions 22. Members 42 are generally cylindrical in shape, have a shorter length than that of catalyst carrier 40, and function as a cushion, and sometimes a seal, for catalyst carrier 40. After the flanges 24 and 26 of the casing halves 14 and 16 have been partly engaged with each other, predetermined magnitudes of loads are applied to the casing halves 14 and 16 in the directions A and B respectively. The magnitudes of the loads are such that they are prevented from destroying or deforming the catalyst carrier 40 or the seal members 42 accommodated in the casing assembly. As a result, the flanges 24 and 26 are forced deeper into each other with their wall surfaces held in contact, until they neighbor each other with the spacing d left therebetween. In order to rigidly connect the casing halves 14 and 16 while maintaining the spacing d, the coupling wall portions 30 and 32 of the flanges 24 and 26 are welded or otherwise jointed, as indicated by reference numeral 44 in FIGS. 3 and 4.
The bent wall portions 28 included in the embodiment of FIG. 3 may be omitted and, instead, the cylindrical wall of the body portion 20 of the casing half 14 may itself be bent in the direction A as shown in FIG. 4. Then, the clamping margin d will be defined between a bent portion 35 where the cylindrical wall of the body portion 20 of the casing half 14 connects to the coupling wall portion 30 of the flange 24 and the end face 36 of the coupling wall portion 32 of the flange 26.
In the catalytic converter 12 in accordance with the present invention, although the catalyst carrier 40 held by the retainer member 38 and the seal members 42 may involve some scatterings in size, the scatterings will be effectively absorbed because the loads applied to the casing halves 14 and 16 are constant and because the clamping margin d is formed when the flanges 24 and 26 of the casing halves 14 and 16 are coupled with each other. Additionally, a certain desirable clamping load acting on the members disposed in the casing halves 14 and 16 is effective to securely fix them in place without damaging them or moving or dislocating them in an undesirable space, which would otherwise be produced when the casing halves 14 and 16 are coupled shallowly.
As shown in FIG. 5, part of the coupling wall portion 30 of each flange 24 may be bent perpendicular to the rest to form an ear 46. This will allow an insulator, such as a cause protecting net, 48 to be anchored to the ear 46 for the purpose of covering the outer periphery of the casing.
While the casing halves 14 and 16 have been shown and described as constituting a catalytic converter assembly 12 which has an oval cross-section, they may be configured to provide the assembly with a substantially circular cross-section as will be described with reference to FIGS. 6 and 7 hereinafter.
Referring to FIGS. 6 and 7, a catalytic converter in accordance with another embodiment of the present invention is shown which is particularly suitable for use with an engine exhaust system of a motorcycle. In these drawings, the same structural elements as those of the first embodiment are designated by like reference numerals and the procedure for assembling two casing halves is essentially identical with the procedure of the first embodiment, and, therefore, description thereof will be omitted for simplicity. In a catalytic converter, generally 50, while the casing body portions 20 for storing the catalyst carrier 40 which is held by the retainer 38 are constructed in substantially the same manner as those of the first embodiment, the tapered portions 22 and coupling portions 18 are absent in the second embodiment. Instead, in the second embodiment, radially outwardly extending flanges 52 and 54 are respectively formed at opposite ends 55, 57 of the casing bodies 20, i.e., opposite ends 55 of the casing half 14 and opposite ends 57 of the casing half 16. The adjacent flanges 52 and 54 are individually connected to an annular, radially inwardly extending flange 58 of a short tubular member 56 which is adapted to mount the catalytic converter 50 at each end of the assembly. The short tube 56 is larger in diameter than the body portions 20 of the catalytic converter 50.
The short tube 56 also has an annular flange 60 which is fit in and rigidly connected to an outer tube 62 whose inside diameter is substantially equal to or larger than the outside diameter of the short tube 56. In this construction, an annular chamber 64 is defined between the outer tube 62 and the casing halves 14 and 16, and a chamber 66 between the outer tube 62 and each short tube 56.
Concerning a motorcycle, a catalytic converter is usually confined directly in a muffler due to design and appearance limitations. The catalytic converter 50 shown in FIGS. 6 and 7 has a construction which conforms to such a situation particular to a motorcycle. The outer tube 62 constitutes a muffler, the short tube 56 constitutes a partition, and the chambers 64 and 66 serve as muffling chambers (expansion chambers). Disposed inside the intermediate muffling chamber 64, the catalytic converter 50 effectively prevents the surface of the outer tube, or muffler, 62 from being burned or thermally damaged, thereby remarkably increasing the durability of the exhaust system.
If desired, as shown in FIG. 8, an annular cushioning member 68 may be disposed between the inwardly extending annular flange 58 of the short tube 56, catalyst carrier 40 and the casing halves 14 and 16.
Thus, in accordance with the present invention, a maximum load (breakdown load) allowable for the catalyst carrier and optimum load for the retainer member and seal members are measured first and, then, the magnitudes of constant loads to be applied to the casing halves in predetermined directions are predetermined based on the resulting data. Further, because the flanges formed on the casing halves have a predetermined length, some dimensional scatterings of the members disposed in the casing assembly can be coped with by suitably adjusting the degree of fitting the flanges. That is, the scatterings will be effectively absorbed by connecting the casing halves in such a coupled position that the spacing, or clamping margin, d is at least larger than zero and of a value which allows the flanges to be coupled. This eliminates the need for setting the margin product by product as in prior art catalytic converters, while preventing the members stored in the casing from being damaged or dislocated thereinside. Therefore, the catalytic converter in accordance with the present invention is stable in quality and excellent in durability. | A monolithic catalyst converter for use with a car, motorcycle or the like for purifying exhaust gas emanating therefrom. A cylindrical casing is made up of longitudinally divided cylindrical casing halves and stores a catalyst carrier which is wrapped in a retainer member. Flanges extend on each of the casing halves in the lengthwise direction of the casing. Predetermined magnitudes of load are applied in predetermined directions to the cylindrical casing to mate the flanges to each other and, in the mating position, the flanges are rigidly connected to each other. | 5 |
This invention relates to a urinal and, more particularly, to a urinal used with a portable toilet structure.
BACKGROUND OF THE INVENTION
Various types of portable restroom units are extensively used at construction sites, outdoor concerts, sporting events, and the like. These portable restroom units are usually chemical units that include a urinal, which is attached to an inner wall surface of the unit. Screws, nails, or the like are used to secure the urinal to the wall, and these attachment screws are applied to the interior of the urinal and are subject to corrosion.
Urinals used in conjunction with chemical portable restroom units are usually connected to the chemical holding tank by means of a short tube to permit drainage into the holding tank. The drainage tube is connected to the drain outlet which projects outwardly from the urinal. The drain outlet for many urinals will accommodate only one sized drain tube, although the drain tubes for holding tanks of the various commercial units include a large or a small sized tube.
Finally, most urinals used with portable restroom units, and known to Applicant, are not provided with a screen for preventing debris from clogging the outlet drain. Certainly, there are no urinals with means for securely locking a screen in place and permitting ready removal of the screen when desired.
SUMMARY OF THE INVENTION
It is an object of this invention to provide a novel and improved molded plastic urinal, of simple and inexpensive construction, which is adapted to be connected to the interior of a portable restroom unit in a manner to minimize corrosion and failure of the securing elements.
Another object of this invention is the provision of a novel molded plastic urinal for use with a portable restroom unit and including a drain outlet integral with the urinal and having large and small diameter portions for accommodating large or small diameter drain tubes.
A further object of this invention is to provide a novel molded plastic urinal for use with a portable restroom unit and including support and locking means for supporting and releasably locking a screen therein.
These and other objects of the invention will be more fully defined in the following Specification.
FIGURES OF THE DRAWING
FIG. 1 is a front elevational view of the novel unit;
FIG. 2 is a rear elevational view thereof;
FIG. 3 is a cross-sectional view taken approximately along the line 3--3 of FIG. 2 and looking in the direction of the arrows;
FIG. 4 is a top plan view of the screen for the urinal; and
FIG. 5 is a cross-sectional view taken approximately along the line 5--5 of FIG. 1 and looking in the direction of the arrows.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings and, more specifically to FIG. 1, it will be seen that the novel urinal, designated generally by the reference numeral 10, is comprised of a single piece molded plastic urinal body 11. The urinal body 11 includes a substantially vertical flat rear wall 12, which terminates downwardly in a lower portion 13, which extends downwardly and forwardly, as best seen in FIG. 2.
The urinal also includes a bottom wall 14, which is integral with the lower wall portion 13 of the rear wall and extends generally upwardly and forwardly therefrom. Referring now to FIG. 1, it will also be noted that the bottom wall 14 is curved transversely and is integral with and merges into the lower portions of the side walls 15.
The side walls 15 are generally vertically disposed and include an upper portion 17 and a lower portion 18. It will be noted that the upper portion 17 of each side wall flares downwardly and outwardly to an enlarged waist 19, and the lower portion 18 flares downwardly and inwardly from the enlarged waist 19 and merges into the lower wall 14. It will also be noted that the side walls flare forwardly and outwardly from the vertical edge lines 20 of the rear wall 12 and then flare forwardly and inwardly and terminate in an inturned flange 21.
The front wall 16 projects generally upwardly and inwardly or rearwardly from the bottom wall and has a vertical dimension substantially less and only a fraction of the vertical dimension of the rear wall 12. Thus, the interior 22 of the urinal body 11, when attached to a wall W, drains rearwardly towards the lower portion 13 of the rear wall 12.
Means are provided for attaching the urinal body 11 to a wall of a portable restroom, and this attachment means includes a substantially flat vertically disposed upper tab 23, which is integral with the rear wall 12 and which projects upwardly therefrom. The upper tab 23 is also integral with an upper, transversely extending generally horizontal flange 24, which is integrally formed with a side wall flange 21 of the side walls 15. It will be seen that the upper tab 23 is of generally rectangular configuration and is provided with a pair of laterally spaced apart openings 25 therein for accommodating nails, screws, rivets, or the like for attaching the urinal to a vertical wall of a portable restroom unit. It will further be noted from FIG. 3 that the rear surface of the upper tab 23 is disposed in coplanar relation with the rear surface of the rear wall 12 so that the rear wall is positioned flush against the vertical wall of the associated portable restroom unit.
The urinal body 11 is also provided with a lower attachment tab 26, which is integrally formed with the urinal body at approximately the juncture line between the lower portion 13 of the rear wall and the bottom wall 14, as best seen in FIG. 3. It will be noted that the lower attachment tab 26 includes a rearwardly inclined portion 27, which is integral with a downwardly projecting terminal portion 28. The downwardly projecting terminal portion 28 has an opening 29 therein for accommodating an attachment element, such as a nail, screw, rivet, or the like.
In the embodiment shown, it will be seen that the downwardly projecting terminal portion 28 has its rear surface disposed in coplanar relation with the rear surface of the rear wall 12. However, it is pointed out that, in certain portable restrooms, the vertical walls are provided with ribs and indentations and the terminal portion 28 in such instances will project rearwardly beyond the general plane of the rear wall 12 for engagement with the recess in the vertical wall. It will further be noted, as best seen in FIG. 1, that the lower attachment tab is centrally located with respect to the bottom wall 14.
The urinal 10 is also provided with a drain opening 30, which is located at the juncture between the lower wall portion 13 of the rear wall and the bottom wall 14, as best seen in FIG. 5. The drain opening 30 communicates with a drain outlet 31 which projects tangentially laterally outwardly and downwardly from the urinal body. It will be noted that the drain outlet 31 is molded integrally with a urinal body and includes a large diameter portion 32, which terminates in a smaller diameter portion 33. It will be noted that the lower arcuate sector of the large and smaller diameter portions is coextensive so that there will be no interference with the flow of liquid by action of gravity through the drain outlet. The drain outlet 31 includes a tapered sector portion 34, which merges into the lower coextensive sector of the drain outlet. With this arrangement, when it is desirable to use a small drain tube with a drain outlet, it is only necessary to slide the small drain tube over the small diameter portion 33 of the drain outlet. On the other hand, if a larger diameter drain tube is to be used in conjunction with the drain outlet, a user will cut the drain outlet 31 along the cut line 35, leaving only the large diameter portion for connection to the drain tube.
The front wall 16 of the urinal body 11 is provided with a centrally located inwardly projecting front locking element 36, which is molded into the front wall and which, in the embodiment shown, is of generally rectangular configuration. The front locking element has a downwardly facing locking surface 37, the function of which will be more fully explained hereinbelow. The front wall 16 is also provided with a molded in outwardly projecting protuberance 38, which is transversely curved, and which presents a supporting shelf 39, the latter being also transversely curved.
The lower portion of the rear wall 12 is also provided with a pair of transversely spaced apart inwardly projecting rear locking elements 40, each of which is of generally rectangular configuration, and each being molded in the lower wall portion 13. Each of the inwardly projecting rear locking elements 40 define a downwardly facing locking surface 41. The lower portion 13 of the rear wall 12 is also provided with an outwardly projecting molded in protuberance 42, which defines a supporting shelf 43, which is transversely curved. It will be noted that the supporting shelf 43 is positioned below the locking surface 41 for the rear locking elements and that the supporting shelf 39 is positioned below the locking surface 37 of the front locking element 36.
The urinal 10 also includes a drain screen or filter, which is of generally rectangular configuration, and which is formed of a suitable flexible plastic material, such as polyethylene or the like. In the embodiment shown, it is preferred that high density polyethylene be used, but that the drain screen 44 be somewhat flexible. It will be seen that the generally rectangular shaped drain screen 44 includes a substantially straight front edge 45, substantially straight parallel side edges 46, and a rear edge 47. The rear edge 47 has a plurality of spaced apart recesses 48 therein which define a pair of laterally spaced apart rearwardly projecting central tabs 49 and a pair of rearwardly projecting outer tabs 50.
The drain screen 44 may be readily inserted in releasably locked relation with respect to the urinal body 11 and, when the screen is installed, the front edge of the screen is positioned under the locking surface 37 of the front locking element, and the front edge is also supported on the supporting shelf 39. The central tabs 49 will be positioned under the downwardly facing locking surfaces 41 of the rear locking elements 40 and the central and outer tabs will be positioned on the supporting shelf 43. Since the supporting shelf 49 and the supporting shelf 43 are curved transversely, the drain screen will be flexed downwardly so that it presents a somewhat downwardly concave upper surface when installed.
The use of the upper and lower tabs located exteriorly of the urinal interior provides means for readily attaching the urinal to a vertical wall of a portable restroom unit and further assures that these attachment elements will not fail as a result of corrosion. The central location of the lower attachment tab in its relation with the upper tab further provides effective means of securing the urinal to the portable restroom unit wall.
The provision of a drain outlet having large and small diameter portions enhances the adaptability of the urinal, since the unit can be used with both a large or small diameter drain tube.
Finally, it will be seen that the molded in support and locking features of the urinal body provide means for effectively locking and supporting the drain screen, which may be readily installed or removed, as desired, for cleaning, replacement or transport.
Thus, it will be seen that I have provided a novel urinal for use with a portable restroom unit, which is not only of simple and inexpensive construction, but one which functions in a more efficient manner than any heretofore known comparable unit. | A urinal for use with a portable restroom unit is formed of plastic and includes a unitary urinal body, including rear, side, bottom and front walls. Front and rear shelves are integral with front and rear walls, respectively, and cooperate with front and rear locking elements for supporting a screen. Attachment tabs project from the rear and bottom walls to permit attachment of the urinal to a wall of the portable restroom unit. A tubular drain tube is integral with the urinal and includes large and small diameter portions to permit selective connection to large and small diameter drain tubes. | 8 |
[0001] This application claims the benefit of U.S. patent application Ser. No. 09/841,164, filed Apr. 25, 2001, the teachings of which are incorporated herein by reference in their entirety.
[0002] This application includes material which is subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by anyone of the patent disclosure, as it appears in the Patent and Trademark Office files or records, but otherwise reserves all copyright rights whatsoever.
FIELD OF THE INVENTION
[0003] The invention relates in general to distributed monitoring of remote sensors, and in particular to novel systems which are useful for remote monitoring of chemical properties or electric current.
BACKGROUND OF THE INVENTION
[0004] Over the last three decades the United States has spent billions of dollars trying to monitor and clean up contaminated ground water and soils as a result of a period in which the industrial expansion of our Nation outpaced our knowledge of safe chemical disposal. Despite large sums of financial investment to protect and recover natural resources, scientists continue to struggle to accurately monitor ground water and detect contaminants, or quantify the effect of contaminants on the ecosystem as a whole. This struggle is due to two primary reasons: 1) there is a lack of advanced, field deployable, environmental sensory systems capable of continuous, long-term monitoring of physical, chemical, and biological measurands, and 2) there are major problems associated with biofouling of the sensors due to nutrient overloading and algae growth.
[0005] The presence of chemicals and complex molecules determines the health of a water source in relation to the ecosystem as a whole, and is typically classified into two groups: primary and secondary contaminants. The former group, which includes heavy metals, radionucliotides, and dioxins, is often characterized as those contaminants that are stable in nature and resist breakdown due to sunlight or temperature, or do not dissolve easily into a water system. These primary contaminants often lead to localized hot spots within an ecosystem, resulting in complete devastation of the normal localized aquatic balance in addition to becoming a point source for continuous contamination for decades to come. By contrast, the latter group is known as the effect group, and is characterized by the overall change in traditional water quality monitoring parameters which include dissolved oxygen (DO), pH, dissolved solids, nitrate-nitrite nitrogen (NNN), and total phosphorous (TP).
[0006] Historically, monitoring of contaminants or their effects has been done through discrete sampling of contaminated sites at random intervals. The samples are then processed off-line through wet-chemistry methods, often several days or weeks after the sample was gathered. The most significant impact of this methodology is that notification of events affecting the change in water quality parameters do not occur until after the change has caused some form of catastrophic event, such as illness or death in humans or an entire stretch of river dying due to total consumption of dissolved oxygen. Additionally, discrete random sampling also causes uncertainty; with no temporal correlation of the data, it is often difficult to determine what was a cause and what was an effect.
[0007] Sensor technology for measuring contaminants or their effects on the ecosystem continues to improve. Optical-based sensors are especially promising due to their inherent advantages with respect to sensitivity, large dynamic range, immunity to electromagnetic interference, and lightweight profiles. For example, optical techniques demonstrating heavy metals detection and classification have been published as have techniques for detecting biological agents, H 2 S, and the aforementioned water quality parameters NNN, CO 2 , DO, and pH.
[0008] Unfortunately, sensor technology for detection is not the total solution. Real-world problems such as biofouling, environmental extremes, and issues involving data, such as transport mechanisms, storage, and analysis, need to be addressed in parallel with improvements in sensor technology to affect significant advances in monitoring the world's natural resources.
[0009] As with the field of environmental monitoring discussed above, monitoring technologies in the field of electrical power generation, distribution, and transmission have also been subjected to technical limitations and inefficiencies. Having timely knowledge of past and present static and dynamic states in power generation facilities and distribution and transmission grids is critical in decision making, power scheduling, billing, model studies, planning protection, and maintenance. To date, the task of collecting data on a distributed power system has been relegated to a collection of disassociated electronic subsystems scattered throughout the grid. All are ordinarily standalone designs, most having no high-throughput networking provisions and, at best, only the most recent designs employ any digital capability (mass storage, rule-based triggering, adaptive process tailoring, etc.). Most previously installed measurement systems were designed specifically for a particular task and the concept of integrating all measurement components into a single body was not possible for a host of varied reasons. It is not uncommon to find decision-makers located in the control room at a major utility with three or more computer terminals on their desks with virtually no way to pass information between them.
[0010] Within the last few years, the most important pressure upon electric-power utilities has been the result of deregulation and the subsequent economic competition that it has promoted. In order to remain competitive and profitable, providers of electric power have been forced to review all aspects of their operations and seek methods that improve efficiency. Of the numerous areas identified where cost savings could be implemented, improving power transfer efficiency, real-time control of power networks, and detection and prevention of potential line fault conditions through online monitoring all rank in the top target areas for focus and development.
[0011] A major impediment to improved power transfer efficiency is existing transducer technology. Virtually unchanged over the last several decades, conventional current/potential transformers are characterized by their bulkiness, expense, geometry, large volumes of electrical insulation required when used on high-voltage lines, and potential for catastrophic failure. With respect to real-time control of power networks and the detection/prevention of line fault conditions, most types of conventional transformers exhibit significant bandwidth limitations, restricting their usefulness in the monitoring of harmonics and subsequent determination of power quality or the exact timing of line fault events.
[0012] A 1995 article by the Electrical Power Research Institute (EPRI) indicates that a 1% increase in efficiency due to improved sensors and instrumentation in coal-fired generator plants translates to a savings of over $300 million per year. Moreover, a 1% increase in capacity utilization throughout the utilities due to advanced instrumentation would result in over $3 billion in saving per year for the industry.
[0013] On Jul. 2, 1996, a short-circuit on a 345-kV line in Wyoming started a chain of events leading to the breakup and complete islanding of the western North American power system. Loads were very high due to local demand in southern Idaho and Utah because of temperatures around 100° F. Simultaneously, power exports from this region to California were high, causing many of the distribution lines to operate near capacity. A flashover to a tree at 2:24 p.m. initiated a chain of events, and when coupled with the failure of equipment and harmonic instability within the power distribution network, numerous protective devices kicked in to isolate a 5-state area. The impact was a total loss of power for over 15 million commercial and residential customers and a total estimated revenue loss approaching $2,000,000,000. Furthermore, post analysis of the data that does exist from this outage has indicated that if a real-time, bi-directional communications system had been in place, operators or computers would have had approximately 110 seconds to prevent collapse of the entire grid system, potentially saving the utilities and their customers hundreds of millions of dollars.
SUMMARY OF THE INVENTION
[0014] It is therefore an object of the invention to provide an improved system and method for remote monitoring.
[0015] It is a further object of the invention to provide a remote monitoring system and method which provides the capability of delivering sensor data to monitoring facilities in a timely manner, whereby catastrophic environmental or power delivery events can be foreseen and averted or minimized.
[0016] It is a further object of the invention to provide a remote monitoring system and method which can be practiced in a less costly and less labor-intensive manner than those of the prior art.
[0017] In a preferred embodiment, the invention provides a system for gathering, transmitting, and storing data captured from remote monitoring sites positioned in the field, with specific applicability to distributed chemical sensing and reporting, as well as distributed power monitoring and reporting. Transducers monitoring water quality parameters or electrical power parameters have their data transmitted to the Internet or Intranet via a communications link. From here, the data is relayed to secure servers where it is formatted, analyzed, and stored for later retrieval by a customer. If alarm conditions exist that require immediate customer notification, notifications are sent via one or more telecommunications means, including pager, cellular telephone, or email. With respect to the distributed chemical sensing embodiments, the invention preferably utilizes fiber optic chemical sensors that addresses the problem of biofouling. Using anti-fouling measures, the invention can provide continuous, long-term waterway monitoring. With respect to distributed power monitoring and reporting, the invention preferably utilizes a fiber optic optical current transducer system for the measurement of magnetic fields in electric power and power electronic applications. The transducer is based upon rare-earth iron garnet (REIG) crystals that exhibit the Faraday effect when placed in a magnetic field. This transducer is extremely lightweight, making retrofitting of existing distributed power monitoring grids extremely cost effective. In both cases, the respective sensor technologies are coupled with wireless telecommunications and network infrastructures to provide businesses with the ability to shift from a reactive to a proactive mode of operation, enabling them to become more efficient in their business operations.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] The foregoing and other objects, features, and advantages of the invention will be apparent from the following more particular description of preferred embodiments as illustrated in the accompanying drawings, in which reference characters refer to the same parts throughout the various views. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating principles of the invention.
[0019] FIG. 1 is a block diagram illustrating the overall operation of the hardware and software of the system of the invention in accordance with a preferred embodiment.
[0020] FIG. 2 is a block diagram illustrating the basic functions of the remote field unit of the invention.
[0021] FIG. 3 is a functional block diagram illustrating the solar array power subsystem of the invention.
[0022] FIG. 4 is a state diagram illustrating the modes of operation for the RFU of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0023] FIG. 1 is a block diagram illustrating overall hardware and software system operation of the present invention in accordance with a preferred embodiment. Transducers that monitor water quality parameters or electrical power parameters have their data transmitted to the Internet or Intranet via a communications link. From here, the data is relayed to secure servers, where it is formatted, analyzed, and stored for later retrieval by a customer. If alarm conditions exist that require immediate customer notification, such notifications are sent to a customer via one or more telecommunications means, including pager, cellular telephone, or email. Other known means for providing such notification over a telecommunications network are possible without departing from the spirit and scope of the invention.
[0024] The following sections further describe detail and options surrounding the preferred system implementation.
[0025] Field Implementation—Hardware Configuration
[0026] A preferred remote field unit (RFU) is considered a ground-based satellite and, as such, is completely autonomous. An RFU can contain units performing various functions, including:
A sensor function, A signal processing function, A control function, A power function, A tamper function, A global positioning system (GPS) function, and A two-way telemetry function.
[0034] FIG. 2 shows the relationship of the above functions; an overview of their operation follows.
[0035] Sensor Function
[0036] The sensor function is a physical interface between a quantity being measured and an RFU. Possible sensor inputs are listed in the lower left corner of FIG. 1 . This list is not considered exhaustive; other possible sensor input will be apparent to those skilled in the art. Multiple sensors can form the sensor function.
[0037] Signal Processing Function
[0038] A signal processing function preferably contains three inputs or input sets: (1) a set of inputs from a sensor function, (2) a set of inputs from a control function, and (3) a set of inputs from a power function. Additionally, a signal processing block can contain a set of outputs to a control function. The primary task of a signal processing block is to convert physical signal(s) from a sensor function to numerical representations of a measured signal. The signal processing function is under program control from the control function, from where it derives all algorithmic manipulations of the sensor signal(s), timing information, and self-diagnostic instructions. The signal processing function derives its power from the power function.
[0039] The output of this block consists of formatted sensor data as well as control, indicator, and diagnostic information.
[0040] Contained within this function are all electronics and optics necessary to convert the signals from the sensor function to their representative values. Additionally, inputs from third-party devices are included in this function.
[0041] Control Function
[0042] The control function preferably operates under program control and is a state machine. A preferred control block embodiment can receive five inputs: (1) a set of inputs comprised of formatted sensor data as well as control, indicator, and diagnostic information from the signal processing function, (2) a set of inputs comprised of indicator information from tamper alarms, (3) a set of inputs comprised of control data as well as control, indicator, and diagnostic information from the telemetry function, (4) a set of inputs from the global positioning system, and (5) a set of inputs from the power function.
[0043] A preferred control block embodiment can also receive two inputs: (1) a set of outputs to the signal processing function and (2) a set of outputs to the telemetry function. The set of outputs to the signal processing function are used to acknowledge data sent from the signal processing function as well as to control the mode of operation of the signal processing function. The set of outputs to the telemetry function is used to transfer sensor data to the telemetry function as well as control information.
[0044] The control function is the “heart” of the RFU. Depending upon the mode of operation, the control function will orchestrate all inter-processor communications, diagnostic functions, as well as data formatting, storage, and relaying. Additionally, the control function will perform periodic “state-of-health” diagnostics of all system parameters to ensure proper operation. Finally, the control function formats system data into a desired data communications protocol or protocols, and translates incoming formats into system command sequences.
[0045] Telemetry Function
[0046] The telemetry function serves the purpose of transmitting data from the RFU as well as receiving data intended for the RFU. Telemetry can be implemented through a variety of hardware implementations, depending upon the physical RFU geographic location or anticipated RFU functionality. Such hardware implementations can include, but are not limited to:
[0047] (1) Wireline interface,
[0048] (2) Wireless point-to-point radio-frequency (PPRF) interface,
[0049] (3) Wireless cellular interface, and
[0050] (4) Wireless RF satellite interface.
[0051] Wireline interfaces are preferably implemented whenever there is a direct connection available to plain old telephone service, known in the telecom industry as POTS. This would allow the RFU to directly dial into the Internet/Intranet via a local service provider (ISP), and as of this writing, is the most cost-effective data transfer methodology.
[0052] Wireless PPRF interfaces are preferably implemented whenever POTS is not available. This configuration increases overall initial system costs due to the need for multiple transceivers, but over time becomes the next cost-effective data transfer methodology. An RFU would connect via direct radio link to a corresponding base unit, the latter directly connected to POTS.
[0053] An alternative PPRF implementation can allow an RFU to transmit data from other RFUs. In this embodiment, an RFU which is incapable of directly transmitting data to a base unit can transmit data to another RFU, which can in turn transmit received data, as well as data collected at the RFU, to another RFU or directly to a base unit, if such a base unit is available. An RFU receiving data from another RFU may store received data, or may open communications with another RFU or base station and retransmit such data as it is received.
[0054] Wireless cellular interfaces are preferably implemented when POTS is not available, PPRF is not desired or practical, and cellular coverage is assured. As with a POTS implementation, an RFU can directly dial into the Internet/Intranet via an ISP. This is the next mostly costly alternative due to the monthly charges of cellular airtime.
[0055] Finally, wireless RF satellite interfaces can be used any time the previous telemetry options are not available. This option represents the greatest cost to the customer due to the costs of satellite bandwidth usage.
[0056] Tamper Function
[0057] The tamper function is incorporated into the RFU and provides alarm notification that the system is being tampered with or that diagnostics have failed. This is an output-only function that provides its status word to the control function.
[0058] GPS Function
[0059] The GPS function serves two purposes: (1) provide a very precise (<10e-5 second resolution) time stamp to the data, and (2), if the RFU is installed on a mobile platform, provide extremely accurate global positioning information for incorporation into the status word. The former is used to specifically time-correlate multiple RFU data sets at the network operations center, with the latter can be used by RFUs that are mobile in design (such as autonomous underwater vehicles).
[0060] Power Function
[0061] The power system can be driven from standard electrical or battery power where delivery and maintenance of such power is economically feasible. Alternatively, power can be generated at or near an RFU through a variety of alternative energy means, including, but not limited to, solar power, hydrodynamic power, or windmills. The latter represents the most probable solution for the majority of the RFUs.
[0062] FIG. 3 illustrates a preferred power system embodiment which utilizes solar power. Such a power system can consist of a solar array panel, a power system regulator, and a battery. The function of each of the blocks is straightforward and is explained below.
[0063] Solar Array. The solar array function converts light from the sun into useable energy. Array output can typically fluctuate from 0 (darkness) to nearly 22 vdc in direct sunlight, no load.
[0064] Power System Regulator (PSR). The PSR's primary goal is to ensure that the load bus remains at constant voltage, independent of the input from the solar array or battery. To accomplish this, the PSR is comprised of both a buck and boost regulator.
[0065] The boost regulator is activated any time the battery voltage drops below the bus regulation voltage, typically 12 vdc. At the expense of a greater drain in power on the battery, a load bus can be maintained at or near bus regulation voltage.
[0066] The buck regulator performs the opposite function—any time the bus voltage exceeds the normal setpoint value the buck regulator will reduce the amount of voltage on the bus by either 1) shunting energy through large MOSFETs connected to a heatsink, or 2) delivering the excess energy to the battery charger circuit so that the battery reserves are maintained.
[0067] Battery. This is typically a gelled electrolyte battery that has the advantage of not stratifying like conventional lead-acid types. The use of “environmentally friendly” batteries that are non-spillable and sealed are preferably used so that transport to the installation site will require no additional safety precautions.
[0068] A PSR monitoring function can provide digital and analog outputs to indicate PSR status. Typically, most PSRs use binary bits to indicate current operational mode (boost, charging, floating, and the like) and any abnormal conditions. Analog outputs are scaled voltages of the amount of voltage being produced by the array, the load on the battery (from the load bus), and the charging current to the battery. This information may be integrated into the status word reported from the remote site.
[0069] Field Implementation—Modes of Operation
[0070] The RFU is preferably a state machine operating under program control. Three principle modes of operation are preferably provided: standby (STBY), runtime (RUN), and transmission/reception (RF). FIG. 4 is a state diagram illustrating preferred RFU operation modes and their interoperation. Each mode is described below.
[0071] STBY State
[0072] The duty cycle of data collection can span from as little as one sample per day to nearly continuous sampling. For those situations or applications where continuous sampling is not required or when RFU communication is not necessary, power-consuming devices such as sensors, a controller, and a transceiver, can be taken offline to minimize power system battery drain, thereby extending battery lifetime.
[0073] Processor functions are under program control. Timing is provided by an onboard watchdog timer that also provides a master timestamp for all data gathered. While in standby mode, a processor can run “scrub” operations, including diagnostics and peripheral scans of the tamper switches.
[0074] In the event diagnostic or tamper switches indicate an abnormality, the processor will power the system and attempt to immediately transmit an alarm notification. After alarm transmission and acknowledgement reception, the system will return to STBY mode.
[0075] RUN State
[0076] The RUN state is the data collection mode, and can be attained from the RUN state, RF state or the STBY state. At predetermined times under program control, the system can initiate an environmental data sampling cycle. If in the STBY state, power will be applied to the data collection circuitry. After a warm-up requirement has been met data will be gathered from the system. After processing, the data will be stored onboard in memory until emptied by a transition from the RUN to RF states. If the program indicates a return to the STBY state the power to the data collection circuitry will be removed until the next acquisition period.
[0077] The RUN state can also be entered from the RF state. After data transfer, if the program indicates that continuous monitoring is required, the system will return to data collection mode and will log data as previously described.
[0078] Finally, RUN state is reentrant. If the program determines that continuous data collection is required, but it is not time to transmit, then the sequence will loop until a transition to the RF state occurs.
[0079] RF State
[0080] RF state can be entered from either the STBY state or from the RUN state, as in the case where data must be offloaded. There are two conditions that may cause the RF state to be entered from STBY state: alarm and receive. If an alarm is generated, power will be applied to the transceiver and data will be formatted and sent to the transceiver. After reception of the acknowledgement, the system will transition back to the STBY state, deenergizing the transceiver.
[0081] The remote system may also be configured to receive commands while still conserving battery life. This is accomplished by the setting processor's watchdog timer to an appropriate interval. Each time the watchdog timer “wakes up” the processor, it turns on the receiver and listens for a predetermined length of time. If there is no information “on the air”, the receiver is turned off and the processor returns to the low power STBY state. If there is information, the information is received, passed to the processor, and the appropriate action taken. System designers can extend the life of the battery by increasing the time between receive intervals at the expense of control delay. The interval itself may be modified. This will allow the system to be more interactive when necessary.
[0082] If entry to the RF state occurred from the RUN state, the system will transmit the data stream and upon receipt of the acknowledgement, will return to the RUN state to collect data.
[0083] In an alternative embodiment, an RFU can alternate between RUN and STBY states independent of data transmission needs. Data collected by an RFU can be stored in a first in, first out (FIFO) queue; database; or other data storage system. Such data can then be read as necessary by a data transmission system. Data transmission can begin at the occurrence of one or more events, such as elapsing of a specific time interval or collection of a requisite number of data samples. Transmitted data may be removed from a data storage system, thereby reducing RFU data storage requirements. As with the previously described embodiment, a watchdog timer or other device can trigger periodic monitoring for inbound data.
[0084] Field Implementation—Deployment
[0085] The RFU can be fixed or mobile in configuration. Examples of fixed unit locations for water quality monitoring are effluent monitoring points, lakes, streams, rivers, aquifers, etc. Examples of fixed unit locations for the power monitoring industry are at tie points between generation and transmission subsystems, as well as between transmission and distribution subsystems.
[0086] Mobile applications for RFUs are envisioned using remote, autonomous underwater vehicles to sample the water column. This system could be the basis of a world-wide ocean or river observing system and would provide tremendous information concerning the changing ecosystems surrounding our waterways.
[0087] Telecommunications Considerations
[0088] Locations for monitoring sites will vary widely. For this reason, there is no single solution that is appropriate for all locations. Two factors must be considered with designing the communication link between the remote system and the host: Total Life Cycle Cost and availability. To achieve an optimum communication link, the link that meets the availability criteria at the lowest Total Life Cycle cost will be selected.
[0089] Communications link options will include, but are not limited to: land telephone lines (POTS), wireless land mobile, unlicensed Part 15 systems, AMPS Cellular (including CDPD and Cellemetry), RAM Mobile Data, ARDIS, and satellite systems (PanAm, Teleos, Orbcomm, Inmarsat-C, Argos, Qualcomm, Hughes, others) as available. The selection procedure should take into consideration the location of the remote site (terrain and coverage from communications providers) as well as the Total Life Cycle Cost of the system. Mixed systems may also be provided. These may use a combination of different communications systems to make a single link. For example, an inexpensive Part 15 device to transmit from a location with no phone line to a location with phone service (potentially saving thousands of dollars in special charges to run the phone line to the remote site).
[0090] Host Implementation
[0091] A single T1 or other high speed data communications line may provide bandwidth for a plurality of remote units. The exact number of such remote units supported by such a data communications line will depend on RFU sampling frequency and data size, but it is anticipated that a T1 line will easily support as many as 100 remote units.
[0092] Data received through such a data communications line may pass through a firewall computer to dedicated servers. Such servers can be built upon a SCSI backbone with RAID redundancy, and can both store incoming data and service user requests. To ensure maximum reliability and minimum download time for customers, multiple “redundant” connections to high-speed data networks may also be maintained. Further reliability can be achieved by utilizing a router and/or switch solution that incorporates advanced BGP4 routing technology or other similar technologies. Such a router configuration can allow a system operator to load balance bandwidth through multiple circuits. Such load balancing allows the routers to automatically compensate for any outages by using alternate circuits. The architecture outlined above provides a high availability, scalable data storage, analysis, and presentation platform capable of storing data from a large number of RFU's, storing such data for an indefinite period of time, and providing users with readily accessible data analysis and data presentation capabilities.
[0093] Customer Interaction
[0094] The customer is preferably provided with all RFU data through a standard Internet or Intranet interface, such as, Microsoft's Internet Explorer or Netscape's Communicator browsers running on personal computers. Other forms of visual access may be provided via web-enabled telephones, personal data organizers and assistants, netbooks, and the like. Voice-access may be provided through standard telephones, cellular telephones, and third-part service agencies.
[0095] Software
[0096] The software preferably resides on the host, and may be written in the Java and XML programming languages. This removes most compatibility issues with individual personal computer or other web-enabled platforms, and allows the system to be used by the largest base of customers and interface platforms. Content may be “pushed” from the host to the customer's browser on an as-required basis.
[0097] Data Analysis
[0098] The form of data analysis will be determined by the customer using various methods of selection, including pull-down menus, pre-loaded scripts, etc. The user preferably has the option to load specific algorithm packages onto their local machine or use the host server to perform all analysis. Furthermore, time histories, geographical mapping, and trend analysis are some of the many options available to the customer.
[0099] Database Generation
[0100] RFU data can be time stamped as well as positional stamped (mobile RFUs only). This enables the development of tremendous data sets on the performance of networks in a manner that has never been attempted. In the case of environmental data, these data sets can be correlated with space-based imagery to provide a better picture of developments on the globe. In the case of power system monitoring, disturbance propagation can be tracked and analyzed in a fashion that, before implementation of the present invention, has never been possible.
[0101] RFU/Customer Data Exchange
[0102] Two forms of data exchange are processed by the system: (1) data that is initiated from the customer, such as alarm setpoints, request for diagnostics, current position, and request for immediate sample, and (2) standard reporting data from the RPU. The customer has the ability to set alarm setpoints and notification strategies (pager, telephone, email, etc.) in the event that the RFU data falls outside acceptable limits.
[0103] Distributed Chemical Sensing
[0104] A distributed chemical sensing embodiment of the present invention preferably utilizes a non-mechanical, non-toxic (i.e. non-metal oxide) methodology for protecting optical based sensors from biofouling in many environments, including freshwater, saltwater, wastewater, etc. The anti-biofouling methods of the invention provide remote sensors with the cabability of long-term deployment in aquatic environments without user intervention or mechanical action.
[0105] The preferred anit-fouling means comprises an anti-fouling coating on the optical sensor element. Requiring significantly less maintenance than conventional technologies, these coatings enable the sensors to remain in the field for extended periods of time. This in turn substantially reduces the high maintenance requirements associated with conventional sensor technologies, thus enabling distributed sensing infrastructure development and deployment. Such coatings are taught in more detail in the U.S. Provisional Patent Application entitled “Anti-biofouling Method and Apparatus for Optical Sensors,” filed Apr. 24, 2000, by inventors Paul G. Duncan et. al, the entire disclosure of which is incorporated herein by reference.
[0106] Distributed Power Monitoring and Reporting
[0107] Embodiments of the invention which are designed for distributed monitoring of electrical power generation and transmission preferably use an optical magnetic field sensor element such as that disclosed in co-pending U.S. patent application Ser. No. 09/421,399 entitled “Methods and Apparatus for Optically Measuring Polarization Rotation of Optical Wavefronts Using Rare Earth Iron Gamets,” filed Oct. 21, 1999, the entire disclosure of which is incorporated herein by reference. The extremely high bandwidth (>700 MHz) of such sensor elements is only limited by the speed of the signal processing electronics to convert the optical signal to a control or indicator value. One estimate of the bandwidth needs of the power industry per sensor element is five times the 51 st harmonic of the line frequency, which is approximately 15 kHz, or 45 times lower than the demonstrated 700 MHz limit. For disturbance monitoring, where events occur in microsecond periods, the above-described optical sensors will have no trouble seeing the fault.
[0108] The following are other features of such sensors which are not available with conventional current transducers, and which provide significant advantages in-the present application with respect to deployment and use of large numbers of wide-area sensors and their support systems:
Features Benefits Low cost sensor Immediate savings in investment of transducer technology, allowing greater numbers to be de- ployed. Sensor and interconnect Immune to eletro-magnetic interference is fiber-optic based Intrinsically safe and isolated from high voltages, hence do not contain explosive insulating oils Lightweight Support equiptment can be positioned great distances from the sensing location Sensor can measure high Enables waveform analysis to improve frequency waveforms efficiency and reduce delivery costs Allows utilities to address power quality issues that saves them and their customers money Sensor does not saturate Removes potantial for catastrophic explosions Provides continuous data independent of load conditions
[0109] While the invention has been particularly shown and described with reference to a preferred embodiment thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention. | A system and method for gathering and analyzing data captured from one or more remote sensing units positioned in the field. Remote sensing units preferably utilize optical sensors. Power to sensing unit components is preferably selectively controlled to reduce power consumption. Remote sensing units according to the invention can be used for a variety of purposes, including water quality or electrical power monitoring, and data from such sensing units is preferably transmitted to a secure host terminal via a communications link. The host terminal preferably formats, analyzes, and stores the data for customer review and retrieval. If alarm conditions exist that require immediate customer notification, such notifications can be sent to a customer via one or more telecommunications means. Through the use of the present invention, businesses can shift from a reactive to a proactive mode of monitoring and operation. | 8 |
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a device and process for dewatering combined ash treated in a quench bath.
BACKGROUND OF THE INVENTION
The main by-products of waste incineration include bottom ash which is released directly from the incinerator furnace and fly ash which is collected in the boiler hoppers and from the hoppers of the air pollution control equipment associated with an incinerator or power generation system. With increasing emphasis being placed on providing better air pollution control of incinerator and power generator plant emissions, most, if not all, incineration and power generation systems utilize air pollution control equipment that injects alkalis into a plant's various gas passages and/or combustion zones. As a result, the reacted and unreacted alkalis remain in the ash and particularly in the fly ash.
The unreacted alkalis cause the combustion by-products to exhibit varying degrees of hygroscopicity when the material is quenched. Following quenching, the combined ash often exhibits significant free water run-off or in extreme situations may coat downstream equipment. The water run-off is problematic for downstream conveyors since expensive additional equipment is needed to collect the excess water. Additionally, the relatively wet condition of the material also adversely affects the downstream recovery of ferrous scrap from the waste stream. More critically, the free water run-off increases the potential for pollution resulting from the leaching of toxins contained in the ash into the ground water and aquifers at the disposal sites.
Although a number of treatments for stabilizing combined ash have been proposed, none exist that substantially dewater the combined ash efficiently, quickly and economically without the use of expensive plant equipment, chemical fixation agents or complex mechanical treating devices. Moreover, an apparatus does not exist that takes advantage of pre-existing equipment and that achieves substantial results while making only minor modifications to such equipment.
SUMMARY OF THE INVENTION
In view of the foregoing, therefore, it is apparent that there exists a need for a process and apparatus that provides for an automatic, efficient, simple and inexpensive combined ash dewatering process and apparatus that can be combined with conventional quench bath equipment in order to produce a combined ash having a low moisture content.
It is therefore an object of this invention to provide for a combined ash dewatering system that first collects the combined ash in a quench bath in order to reduce an amount of fugitive dust.
It is a further object of this invention to provide for a dewatering device comprising a vibrating motor that is located along an inclined spout of the quench bath such that the vibrations caused by the vibrating motor cause a substantial dewatering of the combined ash.
It is yet an additional object of the invention to provide for a fly ash dewatering apparatus whereby the eccentricity of the vibrator can be adjusted and the active vibration time periods can be controlled in order to increase or decrease the moisture content of the resulting ash or to adjust the apparatus to the specific characteristics of the combined ash produced by the incinerators/boilers.
These and other objects of the invention are achieved by an apparatus for dewatering combined ash that includes a quench bath having a hydraulically operated ram which reciprocates along a first inclined portion of the quench bath and a vibrating motor on an inclined spout of the quench bath whereby the hydraulic ram pushes combined ash contained in the quench bath slowly off the inclined spout. At the same time, the vibrator causes vibration and dewatering of the ash before it completely exits the inclined spout of the quench bath into a downstream shaking conveyor device. As a result, a substantially dewatered combined ash is produced causing minimum hazards to the downstream equipment and having a minimum impact on the environment.
Features and objects of the present invention will be apparent from the following brief description of the drawings, detailed description of the preferred embodiments, the claims and the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cut-away side view of the combined ash dewatering apparatus according to the present invention;
FIG. 2 is bottom view of the inclined spout portion of the dewatering apparatus of FIG. 1;
FIG. 3 is a top view of the vibrator motor 52 of FIG. 1; and
FIGS. 4a-c show the motor connections and timing chart of the motor of FIG. 3.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to FIG. 1 wherein like reference numeral refer to like parts throughout, FIG. 1 illustrates an apparatus for treating combined ash produced from an incinerator or power generation system.
It is known to provide a discharge and quench bath located at the bottom of the furnace. Typical quench bath systems include a water filled trough which is provided with some form of a displaceable pusher that reciprocates horizontally in order to displace combined ash dropped into the trough. The advantage of a quench bath is that it produces ashes that are cool and sufficiently moistened to prevent escaping fugitive dust from contaminating the plant. Extraneous air is also prevented from entering the furnace chamber by virtue of a fluid seal provided by the water in the quench bath. The water seal also prevents gases and heat from escaping from the incinerator area and causing serious injury to plant employees.
More particularly, as shown in FIG. 1, a quench bath 10 is illustrated. The bath 10 comprises a receptacle 12 having an arcuate shape. The receptacle 12 includes a bottom wall 14 that is curved at the portion located substantially below the point where ashes drop into the receptacle 12 through a chute 16 in the direction of arrows 18. A water bath is provided within the receptacle chamber 12 to a predetermined level 13. The water level 13 is critical since the water forms a seal with the walls 36 and 44 which prevents hot gases and other contaminants produced by the incinerator from escaping into the facility.
The shape of the bottom wall 14 of the quench bath 10 includes a curved bottom portion 24 and a slanting discharge trough portion 22. The bottom wall of the slanting discharge portion 22 is made up in its interior of a plurality of plates 38 in order to prevent the combined ash from sliding back down the inclined trough.
Located within the quench bath 10 and slidable along curved portion 24 is a hydraulically actuated plunger 26 adapted to reciprocate to the end limit shown by the dotted lines. The plunger 26 is connected to a lever arm 30 that is turned about a horizontally disposed shaft 32 back and forth between those positions shown in solid and broken lines.
The plunger 26 is sealed to the curved portion 24 by means of a shoe 42 which is adapted to slide along the curved portion 24. In addition, a seal 40 is provided above the plunger 26 to prevent the admixture of the quench bath liquid that is located below the chute 16 and that is contaminated with particles and debris with the liquid contained behind the plunger 26. The seal, therefore, prevents dirt and debris from getting caught in the pusher. Further sealing of the device is insured by a chute wall 36 under which the pusher 26, in combination with the seal 40, remains substantially in contact throughout the movement of the pusher 26. A second chute wall 44 is also provided. The wall 44 is connected to a transition plate and has a curved portion which is designed to withstand substantial impacts caused by objects contained in the bath that contact the wall 44. The second chute wall 44 is thereby designed to be replaceable.
The dewatering aspects of the invention are provided by a vibrating device 52 which is attached to the lower wall 14 located along a slanting discharge trough 22. Typically, the vibrating device will include a vibrating motor 52 having an eccentric shaft. The examples of the motor include a 1.5 hp unit manufactured by Motomagnetic Vibrators having a 3800 vpm force whose output is approximately 3,000 lbs. per kilogram. The magnet is manufactured by Martin Engineering Co. A larger or smaller motor can be used, as needed, depending on the desired force. However, selecting a larger motor will enable the operator to vary the amount of power and eccentricity to achieve the desired level of dewatering.
The vibrator motor 52 is, in turn, attached to a reinforcement plate 54 that is connected between cross beams that extend along the longitudinal axis of the discharge trough 22. As a result, vibration or motion of the unit 52 is imparted along the rotational direction of the motor across the width of the shaft 22 and oscillations are produced in the direction of arrows A--A.
In operation, when the trough 10 is filled with water to the level 13, ash falls into the shaft 16 in the direction of arrows 18 before the plunger 26. The plunger then reciprocates forward using its transverse push bar 28 to push the material 25 toward the inclined trough 22. The ash moves upward through the inclined trough 22 in a direction indicated by arrow 59. As the plunger 26 returns to the position shown by the solid lines from that shown by the broken lines, the combined ash 25 in the inclined trough 22 is prevented from sliding back by the resistance offered by the ledges of the plates 38.
While the ash 25 moves upward along the slanting discharge trough 22, the electric vibrator 52 is actuated, imparting an oscillatory force substantially vertical to the longitudinal axis of the slanting discharge portion 22. The vertical motion also is imparted across the entire width of the trough 22. The oscillations produce a vibrational effect on the combined ash causing the compression of the materials supplied to the quench bath 10. Since the vibrator motor 52 is located at a point in the trough where the combined ash is above the quench bath level 13, water and/or other liquids contained in the material are squeezed out of the material which then flow down the inclined trough 22 toward the bath 13. A compressed and dewatered material is then pushed out of the quench bath spout following subsequent motion by the plunger 26. As result an average moisture content of between 25-40% is dewatered to an average moisture of 15-25%.
Referring now to FIG. 2, a bottom view of the slanting discharge trough 22 is illustrated. As shown, the reinforcement plate 54 for the vibrator 52 is connected to a plurality of plates 65 that form the bottom wall 14 of the slanting discharge trough 22. The reinforcement plate 54 is connected to the bottom plates through access points 60 which respectively mount the vibrator (not shown). The orientation of the reinforcement plate 54 is perpendicular to cross beams 56 so that vibrations caused by the motor can be imparted across the entire width of the discharge trough 22. However, any suitable mounting design utilizing reinforcement plates, beams or other arrangements is contemplated in order than an even oscillation is imparted across the width of the trough 22.
FIG. 3 illustrates a top view of the vibrating motor 52. As shown, the motor consists of a main body portion 62 having an eccentrically mounted shaft. Eccentricity adjustments are made at ends 64a and 64b. The motor is mounted on the reinforcement plate 54 at the cutout through access points (FIG. 2).
Electrical connections for the motor 52 are shown in FIG. 4a. The motor 52 is connected to a 120 VAC/480 VAC power supply 72. The motor is switched on and off by means of an oscillator circuit 74. The oscillator 74, shown in more detail in FIG. 4c, where it is connected respectively to a relay 78, is in turn connected to the voltage source 72. As a result, the motor is timed on for a discrete time portion T2 and off for the time portion T1, as shown in FIG. 4b. As a result, the motor does not have to run continuously, but can be timed to correspond to the forward position of the plunger 26 so that the wetted combined ash is compacted by the action of the vibrator. Timing control can also be adjusted in order to provide optimal results from different materials that would require more or less moisture. For example, if the present invention is used to dewater fly ash only, then a longer exposure time is necessary than for the combined ash.
In view of the foregoing, it should be apparent that there is provided by the present invention an apparatus for substantially dewatering combined ash by providing a vibrator device located at the exit portion of a quench bath. The dewatering apparatus includes a timing device which allows for the most efficient utilization of the vibrator as the combined ash is moved through the inclined portion of the quench bath. Thus, the present invention reduces the effects of free water run-off, a thixotropic quench bath product and yields a material that is readily handled by downstream conveyors and transport equipment. The present invention ultimately provides a stabilized material that is also ecologically viable.
Although only a preferred embodiment is specifically illustrated and described herein, it would be appreciated that many modifications and variations of the present invention are possible in light of the above teachings and within the purview of the appended claims without departing from the spirit and the intended scope of the invention. For example, the present invention can be applied to numerous materials that require a quenching step prior to disposal. An obvious application of this invention would be to any waste produced by combustion, such as slag or metallurgical waste, without departing from the spirit and intended scope of the invention. | An apparatus and method for dewatering combined ash or other combustion related products. The apparatus aspects of the invention consist of a quench bath having a curved portion containing a plunger adapted to push combustion materials contained in the quench bath up an inclined trough. A vibrator is mounted below a portion of the inclined trough located above the waterline in the quench bath. As a result, material moved up the inclined portion is subject to vibration and compaction resulting in a substantial dewatering of the combustion material. The method of the present invention provides for the steps of quenching, moving and vibrating combustion by-products to obtain a dewatered material having reduced free water run-off. | 5 |
FIELD OF THE INVENTION
The invention relates generally to embodiments of a valve.
BACKGROUND OF THE INVENTION
A valve of the general type under consideration, which may be in the form of, for example, a 2/2-way valve, can be used, for example, for controlling the flow of pressure medium between a pressure medium source and a pressure medium sink. For this purpose, an inlet chamber of the valve is connected via an inlet connection to the pressure medium source and an outlet chamber of the valve is connected via an outlet connection to the pressure medium sink. The valve has a positioning device by which the inlet chamber can be connected to or shut off from the outlet chamber. In the through-flow position the inlet chamber is connected to the outlet chamber and the pressure medium source is therefore connected to the pressure medium sink. In the shut-off position the inlet chamber is disconnected from the outlet chamber and the pressure medium source is therefore disconnected from the pressure medium sink.
The positioning device is usually embodied as a piston. The control of the piston is effected by means of a control chamber, which can be subjected to the pressure medium. The pressure medium can act on the piston via a control face of the piston and thus bring about a movement of the piston. In a configuration of such a valve, which is also referred to as normally closed, the valve is in the shut-off position when the control chamber has been vented. The piston is preloaded by a spring such that the pressure medium cannot flow from the inlet chamber into the outlet chamber. In order to transfer the valve from the shut-off position to the through-flow position, pressurization of the control chamber with the pressure medium is required. During pressurization of the control chamber the pressure medium acts on a control face of the piston, whereby the piston is moved against the force of the spring and therefore opens the path between the inlet chamber and the outlet chamber, so that the pressure medium can flow from the inlet chamber to the outlet chamber.
During pressurization of the control chamber with the pressure medium, the problem can arise that the piston is set into oscillation caused by the activation with the pressure medium, since the piston, in combination with the spring, represents an oscillatory system. This oscillation is undesirable because, firstly, it can cause noise and, secondly, it can even lead to destruction of the valve.
SUMMARY OF THE INVENTION
Generally speaking, it is an object of the invention to provide a valve in which oscillation of the piston or positioning device caused by activation with the pressure medium is avoided.
In accordance with embodiments of the invention, the control chamber is divided into a first chamber and a second chamber, the first chamber being connected to the second chamber. The division of the control chamber leads to a velocity-dependent damping of the movement of the positioning device during pressurization of the control chamber with the pressure medium. The damping is achieved by two effects. Firstly, the pressure medium is braked as it passes from the first to the second chamber. The pressure medium therefore does not act with its full energy on the control face of the positioning device, as in the case of a unitary control chamber. Secondly, as the positioning device moves, an underpressure is produced in the second chamber, since a pressure equalization between the first and second chambers cannot take place correspondingly quickly. The underpressure exerts a force on the positioning device that opposes the movement.
Through the above-described damping, oscillation of the positioning device is prevented. The inventive embodiments therefore enable low-noise and robust valves to be implemented.
Still other objects and advantages of the present invention will in part be obvious and will in part be apparent from the specification.
The present invention accordingly comprises the features of construction, combination of elements, and arrangement of parts all as exemplified in the constructions herein set forth, and the scope of the invention will be indicated in the claims.
BRIEF DESCRIPTION OF THE DRAWING
Exemplary embodiments of the present invention are explained in more detail hereinafter with reference to the appended drawings, in which:
FIG. 1 shows a cross section of a valve known from the prior art,
FIG. 2 shows a cross section of a valve in a first state according to an embodiment of the present invention;
FIG. 2 a shows a cross section of the valve of FIG. 2 in a second state;
FIG. 3 shows a cross section of a valve in a first state according to a further embodiment of the present invention; and
FIG. 3 a shows a cross section of the valve of FIG. 3 in a second state.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 depicts a conventional valve in cross-section. The valve is used to control the flow of pressure medium between an inlet connection 2 and an outlet connection 4 . For this purpose a pressure medium source may, for example, be connected to the input connection 2 and the outlet connection 4 may be connected to a consumer. An inlet chamber 1 can be connected to or disconnected from an outlet chamber 3 by a positioning device 5 . In the position shown in FIG. 1 , the inlet chamber 1 is disconnected from the outlet chamber 3 , so that the pressure medium cannot flow from the inlet connection 2 to the outlet connection 4 .
Control of the positioning device 5 , which is embodied as a piston 5 , is effected via a control chamber 6 . In order to control the positioning device 5 , the control chamber 6 can be connected via a control chamber connection 7 to a pressure medium source or to a pressure medium sink. The position of the valve shown in FIG. 1 corresponds to a connection of the control chamber 6 to a pressure medium sink; The control chamber 6 is vented. The valve is in its shut-off position, since the positioning device 5 is preloaded by a spring 16 such that the pressure medium cannot flow from the inlet chamber 1 into the outlet chamber 3 .
In order to transfer the valve from the shut-off position to the through-flow position, pressurization of the control chamber 6 with the pressure medium is required; that is, the control connection 7 of the control chamber 6 is connected to a pressure source. During pressurization of the control chamber 6 with the pressure medium, the pressure medium acts on a control face of the positioning device 5 , whereby the positioning device 5 is moved against the force of the spring 16 and therefore opens the path between the inlet chamber 1 and the outlet chamber 3 , so that the pressure medium can flow from the inlet chamber 1 to the outlet chamber 3 .
During pressurization of the control chamber 6 with the pressure medium, the problem can arise that the positioning device 5 is set into oscillation caused by the activation with the pressure medium, since the positioning device 5 , in combination with the spring 16 , represents an oscillatory system. This oscillation is undesirable since, firstly, it can cause noise and, secondly, it can even lead to destruction of the valve.
FIG. 2 shows a cross section of a valve according to an embodiment of the present invention. The fundamental operation of the valve corresponds to the operation described above of the valve shown in FIG. 1 , so that a separate description of the fundamental operation is not necessary. According to the depicted embodiment of the invention, the control chamber 6 of the valve is divided into a first chamber 9 and a second chamber 8 . The division of the control chamber is effected by means of a screen 10 . The first chamber 9 is connected to the second chamber 8 via an aperture 11 of the screen 10 . The screen 10 and the aperture 11 of the screen 10 are dimensioned such that they act as a throttle 10 , 11 . The effect of the throttle 10 , 11 is such that, upon pressurization of the first chamber 9 with the pressure medium, the compressed air flowing into the first chamber 9 enters the second chamber 8 in a throttled manner, so that oscillation of the positioning device 5 is avoided.
In order to control the positioning device 5 , the first chamber 9 can be connected to a pressure medium source or to a pressure medium sink. In order to move the valve from its shut-off position shown in FIG. 2 to the through-flow position, the first chamber 9 is subjected to the pressure medium. The pressure medium reaches the second chamber 8 from the first chamber 9 via the aperture 11 of the screen 10 . The pressure medium, which has thus entered the second chamber 8 , acts on the control face of the positioning device 5 and thus causes an actuation of the valve from the shut-off to the through-flow position. The volume of the first chamber 9 is independent of the position of the positioning device 5 , whereas the volume of the second chamber 8 depends on the position of the positioning device. In the through-flow position of the valve the volume of the second chamber 8 is larger than in the shut-off position of the valve.
The division of the control chamber 6 brings about a velocity-dependent damping of the movement of the positioning device 5 during pressurization of the control chamber 6 with the pressure medium. The damping is achieved by two effects. Firstly, the pressure medium is braked as it passes from the first chamber 9 to the second chamber 8 . The pressure medium therefore does not act with its full energy on the control face of the positioning device 5 , as with a unitary control chamber 6 . Secondly, during a movement of the positioning device 5 , which is greater than is necessary to equalize the forces between the gas force and the spring force (oscillation case), an underpressure is produced in the second chamber 8 , since the movement of the positioning device 5 causes an increase in the volume of the second chamber 8 (as shown in FIG. 2 a ) and a pressure equalization between the first chamber 9 and the second chamber 8 cannot take place correspondingly rapidly. The underpressure exerts a force on the positioning device 5 , which opposes the movement.
The above-described damping prevents oscillation of the positioning device 5 . Therefore, low-noise and robust valves can be implemented.
Advantageously, the two chambers 8 , 9 are configured such that the volume of the second chamber 8 is smaller than that of the first chamber 9 . Oscillation of the positioning device 5 is prevented especially effectively by these configurations.
To assist the avoidance of oscillation of the positioning device 5 , the positioning device 5 can additionally have a stepped configuration in the region of the outlet chamber 3 ; that is, the positioning device 5 can be stepped on its side opposite its control face.
FIG. 3 shows an embodiment of the inventive valve that can be used in gas or air dryers as a vent or discharge valve. As compared to the valves shown in FIG. 1 and FIG. 2 , the positioning device 5 is implemented not by a one-piece piston 5 but by a piston head 12 , which is provided with a circumferential seal 13 and is connected to a pressure plate 15 by means of a piston rod 14 . Similar to the valve embodiment described above with respect to FIGS. 2 and 2 a , the movement of piston head 12 can cause an increase in the volume of second chamber 8 , as shown in FIG. 3 a.
An air dryer for a vehicle compressed air system in which the valve according to FIG. 3 can be used is described in DE 11 2005 002 633 T5. In this document the vent or discharge valve is referred to as a purge valve, which is denoted by reference numeral 22 . The purge valve is described, in particular, in paragraphs [0024] and [0030] of DE 11 2005 002 633 T5. According to FIGS. 1 to 3 and paragraph [0024] of this document, the control chamber of the purge valve is formed by a cylindrical section of the body, the cylindrical section being denoted by reference numeral 62 and the body by reference numeral 12 in this document. According to the inventive embodiment of the present application, the cylindrical section of the body, and therefore the control chamber of the purge valve, is divided into two chambers.
Further examples of components/devices in which the valve according to embodiments of the invention can be used include pressure regulators or compressed air supply devices for motor vehicles. Such a compressed air supply device is disclosed, for example, in DE 10 2006 035 772 A1.
It will be seen that the objects set forth above, among those made apparent from the preceding description, are efficiently attained, and since certain changes may be made without departing from the spirit and scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings 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 that, as a matter of language, might be said to fall therebetween. | A valve includes at least one inlet chamber and at least one outlet chamber that can be connected to each other or blocked from each other by means of an actuator. A control chamber is provided for controlling the actuator. The control chamber is divided into a first chamber and a second chamber that are connected to each other. | 5 |
This is a division of application Ser. No. 08/358,627 as originally filed on Dec. 14, 1994, U.S. Pat. No. 6,177,242 which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
FIELD OF THE INVENTION
This invention relates to DNA and clones of β2-subunit of neuronal nicotinic acetylcholine receptor (nAChR) sequences. This invention also relates to genomic DNA fragments containing regulatory and coding sequences for the β2-subunit neuronal nAChR and transgenic animals made using these fragments or mutated fragments. The 5′ flanking sequences contain a promoter, which confers neuron-specific expression. The genomic clones demonstrate the importance of the β2-subunit gene in the nicotinic system and in the pharmacological response to nicotine. The invention also relates to vectors containing the DNA sequences, cells transformed with the vectors, transgenic animals carrying the sequences, and cell lines derived from these transgenic animals. In addition, the invention describes the uses of all of the above.
References cited in this specification appear at the end by author and publication year or by cite number.
Neuron-specific expression. Many recombinant DNA-based procedures require tissue-specific expression. Unwanted or potentially harmful side-effects of gene transfer therapies and procedures can be reduced through correct tissue-specific expression. Furthermore, the ability to direct the expression of certain proteins to one cell type alone advances the ability of scientists to map, identify or purify these cells for important therapeutic or analytical purposes. Where the cells of interest are neurons or a particular subset of neurons, a need for DNA sequences conferring neuron-specific or subset-specific expression exists.
Proteins expressed throughout an organism are often utilized for specific purposes by neurons. By expressing a particular subunit or component of these proteins solely in neuronal tissue, the neuron tailors the protein activity for its purposes. Finding the particular, neuron-specific subunits or components and unraveling why they are produced only in neuronal tissue holds the key to DNA elements conferring neuron-specific expression.
The inventors' knowledge of the biology of acetylcholine receptors provided an important foundation for this invention (see Changeux, The New Biologist, vol. 3, no. 5, pp. 413-429, May 1991). Different types of acetylcholine receptors are found in different tissues and respond to different agonists. One type, the nicotinic acetylcholine receptor (nAChR), responds to nicotine. A subgroup of that type is found only in neurons and is called the neuronal nAChR.
Generally, five subunits make up an acetylcholine receptor complex. The type of subunits in the receptor determines the specificity to agonists. It is the expression pattern of these subunits that controls the localization of particular acetylcholine receptor types to certain cell groups. The genetic mechanisms involved in the acquisition of these specific expression patterns could lead to an ability to control tissue-specific or even a more defined cell group-specific expression. The inventors, work indicates that defined elements in the promoter sequence confer neuron specific expression for the β2-subunit.
The Pharmacological Effects of Nicotine. As noted above, nAChR responds to the agonist nicotine. Nicotine has been implicated in many aspects of behavior including learning and memory (1,2). The pharmacological and behavioral effects of nicotine involve the neuronal nAChRs. Studies using low doses of nicotine (23) or nicotinic agonists (16) suggest that high affinity nAChRs in the brain mediate the effects of nicotine on passive avoidance behavior. Model systems where neuronal nAChR has been altered can therefore provide useful information on the pharmacological effects of nicotine, the role of neuronal nAChR in cognitive processes, nicotine addiction, and dementias involving deficits in the nicotinic system.
Functional neuronal nAChRs are pentameric protein complexes containing at least one type of α-subunit and one type of β-subunit (3-5) (although the α7-subunit can form functional homooligomers in vitro 6,7 ) The β2-subunit was selected for this study from among the 7 known α-subunits and 3 known β-subunits (3) because of its wide expression in the brain (8-10), and the absence of expression of other β-subunits in most brain regions (10). Mutation of this subunit should therefore result in significant deficits in the CNS nicotinic system. The inventors have examined the involvement of the β2-subunit in pharmacology and behavior. Gene targeting was used to mutate the β2-subunit in transgenic mice.
The inventors found that high affinity binding sites for nicotine are absent from the brains of mice homozygous for the β2-subunit mutation, β2−/−. Further, electrophysiological recording from brain slices reveals that thalamic neurons from these mice do not respond to nicotine application. Finally, behavioral tests demonstrate that nicotine no longer augments the performance of β2−/−mice on the test of passive avoidance, a measure of associative learning. Paradoxically, mutant mice are able to perform better than their non-mutant siblings on this task.
BRIEF SUMMARY OF THE INVENTION AND ITS UTILITY
In an aspect of this invention, we describe a 15 kb fragment of DNA carrying regulatory and coding regions for the β2-subunit of the neuronal nAchR. We characterize the promoter of the β2-subunit gene in vitro and in transgenic mice. We describe several DNA elements, including an E-box and other consensus protein-binding sequences involved in the positive regulation of this gene. Moreover, we show that the cell-specific transcription of the β2-subunit promoter involves at least two negative regulatory elements including one located in the transcribed sequence.
Preferred embodiments of these aspects relate to specific promoter sequences and their use in directing neuron-specific expression in various cells and organisms. An 1163 bp sequence and an 862 bp sequence both confer neuron-specific expression. Other embodiments include the −245 to −95 sequence of FIG. 1, containing an essential activator element, and the −245 to −824 sequence of FIG. 1 containing a repressor. A repressor element composed of the NRSE/RE1 sequence is also present in the transcribed region. Certain plasmids comprising these genomic sequences are described as well.
The promoter sequences are important for their ability to direct protein, polypeptide or peptide expression in certain defined cells. For example, in the transgenic mice as shown below, proteins encoding toxins or the like can be directed to neurons to mimic the degradation of those cells in disease states. Others will be evident from the data described below.
Alternatively, the promoters can direct encoded growth factors or oncogenic, tumorigenic, or immortalizing proteins to certain neurons to mimic tumorigenesis. These cells can then be isolated and grown in culture. In another use, the promoter sequences can be operatively linked to reporter sequences in order to identify specific neurons in situ or isolate neurons through cell sorting techniques. The isolated, purified neurons can then be used for in vitro biochemical or genetic analysis. Reporter sequences such as LacZ and Luciferase are described below.
In another aspect of this invention, the inventors provide the genomic clones for mouse β-2 subunit of the neuronal nAChR. These clones are useful in the analysis of the mammalian nicotinic system and the pharmacology of nicotine. The inventors describe assays using transgenic mice where the genomic clones of the β2-subunit have been used to knock out the high affinity binding of nicotine.
In addition to the deletion mutants described, mutations incorporated into the exons or regulatory sequences for the β2-subunit will result in useful mutant transgenic animals. These mutations can be point mutations, deletions or insertions that result in non-efficient activity of the nAChR or even a non-active receptor. With such mutant animals, methods for determining the ability of a compound to restore or modulate the nAChR activity or function are possible and can be devised. Modulation of function can be provided by either up-regulating or down-regulating receptor number, activity, or other compensating mechanisms. Also, methods to determine the ability of a compound to restore or modulate wild type behavior in the behavioral assays described or known (see 17, 22, 18, 2, 19, 21, 23, 24) can be devised with the mutant animals. Behavioral assays comprise, but are not limited to, testing of memory, learning, anxiety, locomotor activity, and attention as compared to the untreated animal or patient. Pharmacological assays (see 12, 13, 14, 15, 20) to select compounds that restore or modulate nAChR-related activity or behavior can thus be performed with the mutant animals provided by this invention. Dose and quantity of possible therapeutic agents will be determined by well-established techniques. (See, for example, reference 16.)
The present model systems comprising transgenic animals or cells derived from these animals can be used to analyze the role of nicotine on learning and behavior, the pharmacology of nicotine, nicotine addiction, and disease states involving deficits in the nicotinic system. In addition, potential therapies for nicotine addiction or deficits in the nicotinic system can be tested with the transgenic animals or the cells and cell lines derived from them or any cell line transfected with a DNA fragment or the complete DNA of phage β2 (CNCM accession number I-1503). These cell lines would include all those obtained directly from homozygous or heterozygous transgenic animals that carry or are mutated in the β2-subunit sequences. In addition, this would include cell lines created in culture using natural β2-subunit sequences or mutated β2-subunit sequences. Techniques used could be, for example, those cited in PCT WO 90/11354.
Dementias, such as Alzheimer's disease, in which the high affinity nicotine binding site are diminished suggest that the present model can be used to screen drugs for compensation of this deficit. Accordingly, methods for screening compounds for the ability to restore or detectably effect activity of the neuronal nicotinic acetylcholine receptor comprising adding the compound to an appropriate cell line or introducing the compound into a transgenic animal can be devised. Transgenic animals and cell lines generated from this invention can be used in these methods. Such animal or cell line systems can also be used to select compounds which could be able to restore or to modulate the activity of the β2 gene.
The transgenic animals obtained with the β2-subunit gene sequence (wildtype or mutated fragments thereof) can be used to generate double transgenic animals. For this purpose the β2-subunit transgenic animal can be mated with other transgenic animals of the same species or with naturally occurring mutant animals of the same species. The resulting double transgenic animal, or cells derived from it, can be used in the same applications as the parent β2-subunit transgenic animal.
Both the promoter sequences and the genomic clones can be used to assay for the presence or absence of regulator proteins. The gel shift assays below exemplify such a use. The sequences or clones can also be used as probes by incorporating or linking markers such as radionuclides, fluorescent compounds, or cross-linking proteins or compounds such as avidin-biotin. These probes can be used to identify or assay proteins, nucleic acids or other compounds involved in neuron action or the acetylcholine receptor system.
Known methods to mutate or modify nucleic acid sequences can be used in conjunction with this invention to generate useful β2 mutant animals, cell lines, or sequences. Such methods include, but are not limited to, point mutations, site-directed mutagenesis, deletion mutations, insertion mutations, mutations obtainable from homologous recombination, and mutations obtainable from chemical or radiation treatment of DNA or cells bearing the DNA. DNA sequencing is used to determine the mutation generated if desired or necessary. The mutant animals, cell lines or sequences are then used in the DNA sequences, systems, assays, methods or processes the inventors describe. The mutated DNA will, by definition, be different, or not identical to the genomic DNA. Mutant animals are also created by mating a first transgenic animal containing the sequences described here or made available by this invention, with a second animal. The second animal can contain DNA that differs from the DNA contained in the first animal. In such a way, various lines of mutant animals can be created.
Furthermore, recombinant DNA techniques are available to mutate the DNA sequences described here, as above, link these DNA sequences to expression vectors, and express the β2-subunit protein or mutant derived from the β2-subunit sequences. The β2-subunit or mutant can thus be analyzed for biochemical or behavioral activity. In such a way, mutated DNA sequences can be generated that prevent the expression of an efficient nAchR.
Alternatively, the promoter sequences described can be used in expression vectors or systems to drive expression of other proteins. Obtainable DNA sequence can thus be linked to the promoter or regulatory sequences the inventors describe in order to transcribe those DNA sequences or produce protein, polypeptide, or peptides encoded by those DNA sequences.
DESCRIPTION OF THE RELATED ART
Previous studies by in situ hybridization (Wada et al., 1989; Hill et al., 1993; Zoli et al., 1994) and immunohistochemistry (Hill et al., 1993) demonstrate that all of the neuronal nAchR subunits cloned to date display a strict neuron-specific distribution. But different subunits exhibit an even tighter distribution to only small subsets of neurons in the brain. For example, the nAchR α2-subunit transcripts are only detected in the Spiriformis lateralis nucleus in the chick diencephalon (Daubas et al., 1990) or the Interpeduncularis nucleus in the rat (Wada et al., 1988). Also the β3, β4 and α3-subunit transcripts are only detected in a small set of structures in vertebrate brain (references in Zoli et al., 1994).
The nAchR, α4, α5, α7, and β2-subunit gene transcripts, in comparison, show a much wider distribution. (Wada et al., 1989; references in Zoli et al., 1994). For example, the β2-subunit transcripts are found in the majority of neurons in the CNS and in all the peripheral neurons that express the nAchR (Role, 1992; Hill et al., 1993).
As a consequence of the differential expression of these subunits, a wide diversity of nAchR species occurs in vertebrates. Each species has a defined pattern of expression involving diverse categories or groups of neurons. For example, the neurons from medial Habenulainterconnect with those from the Interpeduncularis nucleus and yet each express distinct sets of nAchR subunits (see Role, 1992 for review) exhibiting different physiological and pharmacological profiles (Mulle et al., 1991).
Only limited information is available, to date, about the genetic mechanisms that account for regulation of nAchR gene transcription in neurons. Previous work on the promoter of the chick α7 subunit gene analyzed in vitro failed to characterize the DNA elements responsible for transcriptional regulation (Matter-Sadzinski et al., 1992). In another study, the promoter of the α2-subunit gene was partially characterized and a silencer described and sequenced (Bessis et al., 1993, see also Daubas et al. 1993)
Certain evidence leads to the study of the β2-subunit in particular. It is expressed in the majority of the neurons in the brain (Hill et al., 1993). Also, the timing of the appearance of the β2-transcripts closely parallels that of neuronal differentiation (Zoli et al., 1994). We thus decided to study the genetic mechanisms that regulate its transcription.
BRIEF DESCRIPTION OF THE INVENTION
Gene Structure
We have cloned a genomic fragment containing the regulatory sequences and sequences encoding the mouse nAchR β2-subunit gene. The inventors have found that at least part of the regulatory region is conserved among different mammalian species. Particularly, the region between +16 to +38 bp corresponding to the NRSE/RE1 as described in FIG. 1 . Using RNase protection and amplification of primer extension products, we found one main and. three minor transcription start sites (FIG. 1 ). The primer extension experiments were performed using two different reverse transcriptases, with different batches of mRNA and with different primers. These PCR based techniques allowed us to amplify and subclone the same fragments corresponding to transcription start sites rather than reverse transcriptase stops. The transcription start sites that we have characterized are located downstream from the position of the longest rat (Deneris et al., 1988) and human (Anand and Lindstrom, 1990) β2 cDNA 5′ end (see FIG. 1 ). This implies that in human and rat, another transcription start site is used. Such a discrepancy between species has already been demonstrated for the ε-subunit of the muscle nAchR (Dürr et al., 1994, see also Dong et al., 1993; Toussaint et al., 1994). In contrast with the α2 subunit gene (Bessis et al., 1993), no upstream exon could be detected.
Structural analysis of a 1.2 kbp flanking region disclosed many consensus motifs for nuclear protein binding including an Sp1 site and an E-box. Approximately 90 bp of the undeleted 1.2 kb promoter are transcribed and this region contains a NRSE/RE1 sequence (Kraner et al., 1992; Mori et al., 1992). Regulatory elements have already been described downstream of the transcription start site in different systems such as the Polyomavirus (Bourachot et al., 1989) or the fos gene (Lamb et al., 1990).
The promoter region is located between the Eco47 III located in exon 1 (see FIG. 1) (SEQ ID NO:22) and the BamHI site 4.5 kb upstream. One preferred embodiment is the 1163 bp sequence described in FIG. 1 between the EcoRI and Eco47III sites. Regulatory sequences may be located in the 2 kb downstream from the Eco47III site. The regulatory elements from the nAchR β2-subunit sequences can be used to direct the neuron specific expression of a nucleotide sequence encoding a protein, polypeptide or peptide linked to them. Said protein, polypeptide, or peptide can be toxins, trophic factors, neuropeptides, tumorigenic, oncogenic, or immortalizing proteins, or any other protein that can change the function of the neuron.
A 1163 bp Promoter Achieves Cell-Specific Transcription
The 1163 bp promoter contains regulatory sequences for both tissue-specific and temporal specific transcription of the β2-subunit gene. Transient transfection experiments showed that the 1163 bp fragment contains sufficient information to confer cell-specific expression of the nAchR β2-subunit gene. We showed that the same promoter directs a strict cell-specific transcription of the β-galactosidase (β-gal) reporter gene. Moreover, the transgenic construct appears to be activated with the same timing as the endogenous β2-subunit gene during the development of the early embryonic nervous system (Zoli et al., 1994). At later stages of development, most of the peripheral β2 expressing neurons are still labelled (FIGS. 4C, D).
The promoter sequence was tested in transgenic mice by generating two lines (13 and 26) expressing β-gal under the control of the β2-subunit promoter. In CNS, the pattern of β-galactosidase expression is different between the two lines. Only a subset of the cells that normally express β2 express the transgene. This type of discrepancy between the expression of the transgene and the endogenous gene has already been described for the dopamine β-hydroxylase gene promoter (Mercer et al., 1991; Hoyle et al., 1994) or for the GAP-43 gene (Vanselow et al., 1994). Unexpected expression has been observed in transgenic line 13 in the genital tubercule and in skin muscles. This expression is likely to be due to the integration site of the transgene as these tissues are not stained in line 26. To our knowledge, most of the neuronal promoters studied by transgenesis display ectopic expression in a certain small percentage of transgenic lines (Forss-Petter et al., 1990; Kaneda et al., 1991; Banerjee et al., 1992; Hoesche et al., 1993; Logan et al., 1993, Vanselow et al., 1994). However, techniques in the art afford the construction of lines where the expression pattern of the transgene closely mirrors or duplicates that of the original gene. See references for further details showing the success of the transgenesis procedure.
By comparing the β-gal positive cell distribution with those of other known neuronal markers, it becomes apparent that a similarity exists with the distribution of choline acetyltransferase, TrkA (the high affinity nerve growth factor receptor) and p 75 (the low affinity nerve growth factor receptor) expressing cells (Yan and,Johnson, 1988: Pioro and Cuello, 1990a, b; Ringstedt et al., 1993). In particular, in developing rats, p 75 is expressed in almost all the peripheral ganglia and central nuclei (with the exception of the zona incerta and hypothalamic nuclei), which express the transgene (Yan and Johnson, 1988). It is also interesting to note that p 75 expression (like the expression of the β2-promoter transgene) is transient in many peripheral ganglia and brain nuclei, decreasing to undetectable levels at perinatal or early postnatal ages. It is therefore possible that the β2-subunit promoter contains an element controlled by the activation of p 75 , or that both the β2 transgene and p 75 gene are controlled by a common regulator.
In conclusion, although the promoter seems to lack some regulatory elements active in the brain, the existing regulatory elements are sufficient to allow a cell- and development-specific expression of β-galactosidase in the PNS, in the spinal cord, and in several brain structures. The promoter can also be used in assays to identify regulator proteins in neuronal tissue.
DNA Regulatory Elements
To further characterize the DNA elements involved in the transcription of the β2 subunit gene, we deleted or mutated the 1163 bp promoter and analyzed the resulting constructs by transient transfection. A repressor element present in the distal 5′ end region is active in fibroblasts but not in neuroblastomas. This element thus accounts, at least in part, for the neuron-specific expression of the β2-subunit gene. Further analysis of the promoter shows that deleting 589 bp increases the activity in neuroblastomas, but not in fibroblasts (FIG. 6, compare 862 E and 283 E-Luci).
An NRSE/RE1 element is located at the 3′ extremity of the promoter. This element has already been shown to restrict the activity of promoters in neuronal cells (Kraner et al., 1992; Mori et al., 1992; Li et al., 1993). In the 1163 bp promoter of the β2-subunit gene, point mutation of this sequence leads to a ˜100 fold increase of the transcriptional activity in fibroblasts implying that this sequence is involved in the neuron-specific expression of the β2-subunit gene. Moreover, sequence comparison shows that this sequence is highly conserved in rat and human β2-subunit cDNAs (Deneris et al., 1988; Anand and Lindstrom, 1990) as well as in several promoters of genes expressed in the nervous system, such as the middle-weight neurofilament gene, the CAM-L1 gene, the Calbinbin gene, or the cerebellar Ca-binding protein gene (see Table 1 B).
Deletion experiments described in FIG. 6 show that an essential activator element is present between nucleotides −245 and −95. An Sp1 binding site and an E-box could be detected in this region. Sp1 sites are ubiquitous factors, whereas E-boxes have been involved in several genetic regulatory mechanisms in muscle (see Bessereau et al., 1994 for the nAchR α2-subunit) as well as in neurons (Guillemot et al., 1993). Dyad elements have also been reported in some neuronal promoters, such as those of the Tyrosine hydroxylase gene (Yoon and Chikaraishi, 1994), the SCG1O gene (Mori et al., 1990), the GAP43 gene (Nedivi et al., 1992), or in the flanking region of the N-CAM gene (Chen et al., 1990). Results shown in Table 1 A demonstrate that in neuroblastomas, the 1163 bp promoter mutated in the E-box/Dyad is significantly less active than the wild type promoter. Moreover, a gel shift assay (FIG. 7) further demonstrates that the E-box/Dyad is able to bind specific complexes. This suggests that the E-Box/Dyad is responsible for at least part of the activation of β2-subunit gene transcription. However, transactivation experiments of heterologous promoters suggest that the E-box cooperates with the Sp1 site located 27 bp upstream to positively activate transcription. This type of cooperation between an E-Box and an Sp1 binding site has already been demonstrated for the regulation of the muscle nAchR α2-subunit transcription (Bessereau et al., 1993). conclusion, we have shown that the β2-subunit gene is primarily regulated by negatively acting elements and by one positive element that comprises an E-box. This double regulation seems to be a general feature shared by several neuronal genes (Mandel and Mckinnon, 1993) and allows fine tuning of the transcription of neuronal genes. Moreover, our transgenic studies show that the 1163 bp promoter confers a tight neuron-specific expression, but lacks some developmental or CNS-specific regulatory elements.
DESCRIPTION OF THE FIGURES
FIG. 1 : Nucleotide sequence of the region surrounding the initiator ATG of the β2-subunit gene.
The four vertical arrowheads show the four extremities found using RACE-PCR and SLIC, corresponding to the transcription start sites. The vertical arrows indicate the position corresponding to the 5′ end of the longest rat (r) and human (h) β2-subunit cDNA clones (Deneris et al., 1988). The endpoints of the deletions used in the experiments described in FIG. 3 are indicated above the sequence. Nucleotides located in the intron are typed in lower cases.
FIG. 2 : Mapping of the 5′ end of the β2-subunit MRNA.
A. RNase protection experiments. Total RNA from DBA2 mouse brain (5 and 15 μg, lane 2 and 3 respectively) and yeast tRNA (15 μg, lane 1) were hybridized to a 32 P-labeled RNA probe containing 158 nucleotides of intron 1, and 789,nucleotides of upstream sequences (−634/+155). The size of the protected bands were estimated according to the lower mobility in acrylamide of RNA as compared to DNA (Ausubel et al., 1994) and by comparison with the sequence of M13 mp18 primed with the universal primer. The arrow on the left part of the gel points to the major protected band.
B. Identification of the transcription start site using SLIC. The lower part of the Figure shows the strategy and describes the oligonucleotides used for the SLIC or the RACE-PCR. In the SLIC experiment, a primer extension was performed using oligonucleotide pEx3. The first strand of the cDNA was subsequently ligated to oligonucleotides A5′, and the resulting fragment was amplified using oligonucleotides A5′-1/p0 then A5′-2/p1. The amplified fragment was then loaded onto a 1.2% agarose gel. The gel was blotted and hybridized to oligonucleotide p2. Lane 1:5 μg of total DBA2 mouse brain RNA. Lane 2-3: controls respectively without reverse transcriptase and without RNA. Minus: the T4 RNA Polymerase was omitted. Same result was obtained using RACE-PCR.
FIG. 3 : Cell-specific expression of the β2-subunit promoter in vitro.
The luciferase activity of the plasmids were normalized to the activity of the promoterless plasmid (KS-Luci, described in Materials and Methods). RACE-PCR on MRNA extracted from SK-N-Be transfected with EE1.2-Luci, using luciferase oligonucleotides (described in Material and Methods) showed that the amplified fragment had the expected size for the correct transcription
FIG. 4 : Cell-specific expression of the β2-subunit promoter in transgenic mice.
A. Whole mount coloration of E13 embryos. The arrowheads point to ectopic expression in'skin muscles. B. Detection of the β-galactosidase activity in a parasagittal section of an E13 embryo at the lumbo-sacral level. Arrowheads indicate labelling in the ventral and dorsal horn of the spinal cord. C. Detection of the β2-subunit transcripts in an adjacent section of the same embryo. dr: dorsal root ganglion; t : tectum; og orthosympathetic ganglionic chain; tr: trigeminal ganglion.
FIG. 5 : Expression of β-galactosidase in transgenic mice.
A. staining of the retina(re) and the trigeminal ganglia (tr) (E14.5). B. staining of cardiac parasympathetic ganglionic neurons (pg) (E14.5). C. transverse section of the spinal cord (P1). dr: dorsal root ganglion, og: orthosympathetic ganglion. D. Ventral view of the spinal cord (P1). The smaller arrows indicate neurons that have not been identified.
FIG. 6 : Expression of the Luciferase fusion genes containing 5′ end deletions of the β-subunit promoter.
Plasmids are called nnnE-Luci, where nnn is the size in nucleotides of the insertion, and E is the 5′ end restriction site (Eco47 III). The arrow indicates the transcription start site. The activities of EE1.2-Luci are from FIG. 3 .
FIG. 7 : Gel shift experiment. Autoradiogram of the mobility shift experiment. The probe used was a 32 P labelled double stranded E-D oligonucleotide. This oligonucleotide carries E-Box/Dyad element, whereas the oligonucleotide S-E carries the Sp1 binding site as well as the E-Box/Dyad element. The competitor oligonucleotides were used in 10- and 100-fold molar excess, except for S-E that was used only in 100-fold molar excess.
FIG. 8 : Disruption of the gene encoding the β2-subunit of the neuronal nAChR. a-i, Normal genomic structure of the mouse β2-subunit gene. Portion of exon one removed by the recombination event is shaded in light grey. ATG—initiator methionine. Boxes represent exons I-IV. a-ii, Targeting replacement vector used to disrupt the endogenous β2-subunit gene. Initiator methionine and the rest of the first exon were replaced with the coding region of NLS-lacZ and the MCI neo R expression cassette 25 . The construct was able to direct lacZ expression after stable transfection of PC12 cells (not shown), but lacZ expression was never detected in recombinant animals, despite the lack of obvious recombination in the lacZ DNA. Diphtheria toxin-A gene (DTA) 26 was used to select against random integration. a-iii, Structure of the mutated β2-gene. Restriction sites: H, HindIII; R, EcoRI; E, Eco47 III; P, PstI. Black arrows, primers used to detect recombination events in embryonic stem (ES) cells. Grey arrows, primers used to detect the wildtype or mutated β2 genes. b, PCR analysis of tail DNA from a +/+, +/− and a −/−mouse. c, Southern blot analysis of tail DNA restricted with HindIII from the same mice analyzed in panel b. d, Western blot analysis of total brain protein using a monoclonal antibody raised against the β2-subunit.
METHODS: a, The β2-targeting vector was constructed by inserting a multiple cloning site (MCS) into the MCl neo cassette (GTC GAC GGT ACC GCC CGG GCA GGC CTG CTA GCT TAA TTA AGC GGC CGC CTC GAG GGG CCC ATG CAT GGA TCC (SEQ ID NO:30)). A 4.1 kB EcoRI-Eco47III β2-genomic fragment 5′ to the ATG and a 1.5 kB PstI β2-genomic fragment starting within the first intron of the β2-gene were cloned into the MCS. HMl 27, 28 embryonic stem cells (5×10 7 ) were transfected with the linearized targeting vector by electroporation as described 25 . Twenty-four surviving G418-resistant clones were screened by PCR (β2-primer—GCC CAG ACA TAG GTC ACA TGA TGG T (SEQ ID NO:31); neo-primer—GTT TAT TGC AGC TTA TAA TGG TTA CA (SEQ ID NO:32)). Four were positive and were later confirmed by Southern blot analysis. Clones were injected into 3.5-day-old blastocysts from non-agouti, C57BL/6 mice and planted in receptive females. All resulting male chimaeric mice were mated to F1, C57BL/6xDBA/2 non-agouti females. Of 15 chimaeras, one showed germ-line transmission. β2 +/−heterozygotes were mated and offspring were evaluated by PCR analysis (panel b). b, PCR was 35 cycles of 94°/1 min, 65°/2 min and 72°/1 min. c, Southern blotting was performed as described 29 . The 1.5 kB PstI genomic fragment used for the targeting construct was labelled by random priming. d, Western blotting was performed as described 29 using monoclonal antibody 270 11 .
FIG. 9 : Mapping of the neuronal nAChR in mouse brain using in situ hybridization.and tritiated nicotine binding. A, In situ hybridization using antisense oligonucleotide probes based on the sequence of the cDNAs encoding the β2-, α4- and β4-subunits of the nAChR to detect their respective mRNAs in serial sections from the brains of β2+/+, +/− and −/−mice. Midthalamic sections are shown. White arrows indicate the MHb labelled by the β4-antisense oligonucleotide. B, Receptor autoradiography using tritiated nicotine revealing high affinity binding sites in the brains of wildtype, heterozygous and β2-mutant mice. Representative sections at the level of the striatum, thalamus and tectum are shown.
METHODS, A, In situ-hybridization was performed as follows:
In situ hybridization procedure. Frozen tissues were cut- at the cryostat [14 μm thick sections), thaw mounted on poly-1-lysine coated slides and stored at −80° C. for 1-3 days. The procedure was carried out according to Young et. al. (1986). Briefly, sections were fixed with 4% paraformaldehyde for 5 min. at room temperature, washed in phosphate buffered saline (PBS) and then acetylated and delipidated in ethanol and chloroform (5 min.). They were prehybridized for 2-4 h at 37° C. under parafilm coverslips. The composition of the prehybridization and hybridization mixtures was 50% formamide, 0.6 M NaCl, 0.1M dithiothreitol, 10% dextran sulfate, 1 mM ethylenediaminetetraacetic acid (EDTA), 1×Denhardt's solution (50×=1% boyine serumalbumin/1% Ficoll/1% polyvinylpyrrodlidone), 0.1 mg/ml polyA (Boehringer), 0.5 mg/mlyeast RNA (Sigma), 0.05 mg/ml herring sperm DNA (Promega) in 0.02M Tris-HCI, pH 7.5. Probes were applied at a concentration of 2000-3000 Bcq/30 μl section (corresponding to around 15 fmol/section). After removal of coverslips and initial rinse in 2× standard saline citrate (SSC) solution (3 M NaCl/03M sodium citrate) at room temperature (two time for 5 min.), sections were washed four times for 15 min in 2×SSC/50% formamide at 42° C. and, then, two times for 30 min in 1× SSC at room temperature. 1 mM dithiothreitol was added to all washing solutions. After rinsing in ice-cold distilled water and drying, they were exposed for 10-20 days to Hyperfilm βmax (Amersham) and then to a photographic emulsion (NTB2, Kodak) for 1-2 months.
Analysis of histological preparations. The analysis of the labelling pattern for the different mRNAs was carried out both on film and emulsion autoradiograms. Identification of anatomical structures was carried out after counterstaining of the serial sections of the entire embryos with toluidine blue. Definition of anatomical areas in the brain and recognition of peripheral system (PNS) structures was based on different atlases, including The Rat Brain in Stereotaxic Coordinates (Paxinos and Watson, 1986), the Atlas of Developing Rat Brain (Paxinos et al. 1991), the Atlas of Mouse Development (Kaufman, 1992), and the Atlas of the Prenatal Mouse Brain (Schambra et al., 1992). For cranial nerve ganglia development, the plates and descriptions from Altman and Bayer (1982) were consulted. In order to confirm the identification of some central and peripheral structures (e.g., cranial nerve motor nuclei, autonomic motor ganglia) in situ hybridization for choline acetyltransferase was performed on some sections.
A score from 1+(low intensity) to 3+(high intensity) was assigned to the labelling of the anatomical structures based on the subjective evaluation of two experimenters. Background labelling was considered the density of grains in nonneural tissues high cellularity (such as the liver and muscles) or with high density of extracellular matrix (such as cartilage) or the density of labelling over neural structures after displacement with 20× cold probe. In the absence of grain counting at the cellular level, the scores must be regarded with caution. For instance, decreases in labelling intensity of a developing structure may be due to dispersion of positive cells in the structure caused by multiplication of negative cells or formation of neuronal processes. Though the oligonucleotides had the same length and they were labelled according to the same protocol, no attempt to compare the signal intensity or different transcripts was made. Unless specified otherwise, the labeling shown in the pictures has been obtained by using oligonucleotides no. 31 (α3), 47 (α4), 51 (†2), and 62 (α4) (see Table 1 for oligonucleotide characteristics).
Specificity controls. For each mRNA, two to four oligonucleotides were selected in unique parts of the sequence (e.g., the putative cytoplasmic loop between M3 and M4 for nAChR subunits). An initial assessment of the specificity was performed by searching for possible homology with other known sequences in Genbank/EMBL. As histological tests for specificity were considered the following: 1. Two or more oligonucleotide probes for each mRNA gave the same hybridization pattern (FIG. 1 ). 2. The pattern of labelling in central structures in the adult rat was in agreement with that observed by other authors (Wada et al., 1989; Dineley-Miller and Patrick, 1992). 3. Given that most oligonucleotides used were 45-mers with similar GC content (Table 1), each oligonucleotide probe constituted a control for the specificity of the others. 4. The addition to the hybridization mixture of a 20-fold excess of cold probe produced a complete disappearance of the labelling (FIG. 2 ).
The oligonucleotide probes used fulfilled all these criteria, with the exception of the four probes against α3 mRNA, which did not satisfy criterion 2. Previous studies based on cRNA probes showed a relatively widespread distribution of this subunit mRNA in adult rats, notably high levels in the cerebral cortex layer IV, entorhinal cortex layer II, anterior and ventral thalamic nuclei, medial and lateral geniculate nuclei, medial habenula, posterior hypothalamus and supramammillary nuclei, pineal gland, motor nuclei of the V and VII nerves, locus coeruleus, nucleus ambiguus, and area postrema (Wada et al. 1989). At variance with these observations, in adult rats we could detect high levels of α3 mRNA signal only in the medial habenula, intermediate in the pineal gland, area postrema, motor nucleus of the V nerve and cerebellum, low in a few thalamic nuclei and locus coeruleus. Part of the discrepancy may be ascribed to a lower sensitivity of oligonucleotide probes versus riboprobes. However, considering the difficulty of carrying out specificity controls for cRNA probes, especially when hydrolysis of the probe is performed in the histological procedure (Wada et al., 1989), it is possible that some labelling previously attributed to α3 mRNA actually derives from hybridization to other (nAChR-related) RNA sequences. Oligonucleotides: β2: 5′-TCG CAT GTG GTC CGC AAT GAA GCG TAC GCC ATC CAC TGC TTC CCG-3′(SEQ ID NO:1); α4: 5′-CCT TCT CAA CCT CTG ATG TCT TCA AGT CAG GGA CCT CAA GGG GGG-3′(SEQ ID NO: 2); β4: 5′-ACC AGG,CTG ACT TCA AGA CCG GGA CGC TTC ATG AAG AGG AAG GTG-3′(SEQ ID NO:3). B, 3 H-nicotine binding was performed as described by Clarke et al 30 . Fourteen μm coronal sections were incubated at room temperature for 30 min. in 50 mM Tris pH 7.4/8 mM CaCl 2 /4 nM 3 H-L-nicotine. Nonspecific binding was evaluated in the presence of 10 μM L-nicotine bitartrate. Following incubation, sections were rinsed 2×2 min. in ice cold PBS and briefly rinsed in ice cold water. Slides were exposed for 60 days to Hyperfilm 3 H.
FIGS. 10 A and 10 B: Patch clamp recording of nicotine evoked currents in the MHb and anterior thalamus of β2+/+ and −/−mice. FIG. 10A, Representative recordings from cells in the MHb and the anterior thalamus of wildtype and β2−/−mice. The off-rate of the agonist is significantly greater in the MHb than in the anterior thalamus, resulting in a different kinetics of response in the two structures. The response to nicotinic agonists of the MHb is maintained in β2−/− animals, while the response to nicotinic agonists of the anterior thalamus is completely abolished in β2 −/−mice. FIG. 10B, table of responses to nicotinic agonists in various nuclei of β2+/+ and −/−mice.
METHODS, Coronal slices were obtained from the thalamus of 8-12 day old mice using a Dosaka slicer in ice cold ACSF medium (125 mM NaCl/26 mM NaHCO 3 /25 mM Glucose/1.25 mM NaH 2 PO 4 /2.5 mM KCl 2.5/2 mM CaCl 2 /1 mM MgCl 2 pH 7.3). Slices were maintained in the same medium for 1-8 hours. Cells in slices were-visualized through a Zeiss microscope. Whole cell recordings were obtained with 2-4 MOhm hard-glass pipettes containing 150 mM CsCl/l0 mM EGTA/10 mM HEPES/4 mM di-sodium ATP/4 mM MgCl 2 pH adjusted to 7.3 with KOH. Five to ten sec. pulses of drug were applied rapidly to the cell through a 50 μM diameter pipette above the slice, fed by gravity with a solution containing 150 mM NaCl/10 mM Hepes/2.5 mM KCl/2 mM CaCl 2 /1 mM MgCl 2 . Recordings were made in the presence of CNQX (5 μM) and of the GABA A antagonist SR-95531 (10 μM). Currents were recorded with an Axopatch ID (Axon Instrument) patch amplifier, digitized on a Compaq PC and further analyzed with the PClamp program (Axon Instrument).
FIGS. 11 A and 11 B: Performance of β2−/−mice and their wildtype siblings on the passive avoidance test. FIG. 11A, response to various levels of footshock in retention test following a post-training injection of either vehicle or nicotine (10 μg/kg). Average step-through latency during the training trial was 17.0+/−3.6 sec for mutant mice and 15.0+/−3.5 sec for their nonmutant siblings. FIG. 11B, bar graph showing the difference in retention latency between wildtype and homozygous β2 mutant mice injected with either vehicle or nicotine (10 μg/kg) at foot shock intensity of 2.00 mAmp. Data are represented as means +/−S.E.M. of the following groups: wildtype+vehicle (n=27); wildtype+nicotine (n=23); β2-mutant mice+vehicle (n=17); β2-mutant mice+nicotine (n=17). Statistical analysis was performed using a mixed factorial analysis of variance followed by a-posteriori testing of simple effects. #, p<0.05, wildtype vs mutant mice following vehicle injection; *, p<0.01, nicotine vs vehicle in wildtype mice.
METHODS, Passive avoidance test was performed as described in the text, according to Nordberg and Bergh 20 and Faiman et al 20 . Nicotine (bitartrate, Sigma) was freshly dissolved in PBS. IP injection of the same volume of either nicotine or vehicle immediately followed fbotshock during the training trial.
FIG. 12 : Phage and plasmids containing all or part of the β2-subunit gene and the promoter. In the names of the plasmids, the numerals indicate the size of the fragment and the letters indicate the restriction sites used to generate it.
DETAILED DESCRIPTION
The descriptions and examples below are exemplary of the embodiments and scope of this invention. The invention is not limited to the scope of this description. Furthermore, this description together with the accompanying sections of this specification and the material incorporated by reference enables the practice of all of the claims which follow.
The examples and embodiments that follow of course can be modified by techniques known in the art. Variations in the nucleic acid sequences described or claimed can be produced by known methods without altering the effects or advantages the inventors have shown. Such variations are therefore included within the scope of this description and invention.
Materials and Methods
Isolation of Genomic Clones.
The PCX49 plasmid (Deneris et al., 1988) containing the entire rat cDNA (kindly provided by Drs. J. Boulter and S. Heinemann, The Salk Institute, San Diego, Calif.) was cut with EcoRI, the ˜2.2 kb fragment was isolated and used as a probe to screen an EMBL3 bacteriophage library of mouse DBA2 genomic DNA. One unique clone was obtained spanning ˜15 kb of DNA upstream and ˜5 kb downstream from the first exon. FIG. 1 shows the nucleotide sequence of 1.2 kb upstream from the initiator ATG.
Hybridization conditions can be modified by known techniques 29 to determine stringent conditions for this probe. Changes in the hybridization conditions such as temperature (from about 45° C. to about 60° C.) and SSC buffer concentration (from about 0.1×SSC to about 6×SSC), as well as changes in the temperature of and the buffer for the washing conditions can be made to develop sufficiently stringent conditions that allow hybridization to the β2-subunit sequences. Other related sequences can thus be isolated from other libraries based on this hybridization procedure. Human sequences will be isolated by using hybridization conditions such as 45° C. and 6×SSC.
Three deposits were made on Dec. 13, 1994 at the Collection Nationale de Cultures de Microorganismes (CNCM), Institut Pasteur, 25 Rue du Docteur Roux, 75724 PARIS CEDEX 15, France. A phage, λβ2 nAchR, is deposited under the accession number I-1503. This phage contains 15-20 kb of genomic DNA including the promoter sequences and the coding sequences for all of the exons of the murine β2-subunit of neuronal nAchR. Two E.coli cultures bearing plasmids have also been deposited. Plasmid pSA9 in E. coli DH5α has accession number I-1501 and contains 9 kb of murine genomic DNA including the regulatory sequences and regions coding for exons 1, 2 and 3 of the β2-subunit. Plasmid pEA5 in E. coli DH5α has accession number I-1502 and contains 5 kb of murine genomic DNA including a region of about 1.2 kb upstream of the Eco47-III site and a region coding for exons 1 to 5 of the β2-subunit. The inventors intend to deposit the nucleotide sequence data reported here in the EMBL, GenBank and DDBJ Nucleotide Sequence Databases under the accession number: X82655.
Mapping of the Transcription Initiation Site.
For the mRNA mapping, we used different batches of total RNA extracted from DBA2 embryos at stage E13 or E15. The RNA samples were first digested with DNase I to avoid DNA contamination.
RNase protection. An XbaI/PstI fragment containing part of intron 1 was inserted into Bluescript SK (Stratagene). The plasmid was then linearized by BgIII, and an RNA probe was synthesized using the T7 promoter. The protection experiments were then performed as described in Ausubel et al. (1994).
RACE-PCR (Frohman et al., 1988). The mRNA was hybridized 5 minutes at 80° C. with 10 pmol of primer. The synthesis of the cDNA was performed using 400 u MMLV (Gibco) for 45 minutes at 37° C. in the buffer recommended by the supplier. After a phenol/chloroform extraction, the cDNA was ethanol precipitated. The terminal transferase reaction was performed in 0.2 M potassium cacodylate; 25 mM Tris-HCl pH 6.6; 25 mg/ml BSA; 1.5 mMCoCl 2 ; 50 nM DATP and 50 u Terminal transferase (Boehringer) for 30 minutes at 37° C. After phenol/chloroform extraction and ethanol precipitation, one tenth of the terminal transferase reaction was amplified using Promega's Taq DNA polymerase (30 cycles, 1 minute at: 94° C.; 55° C.; 72° C.). The amplified. fragment was then loaded on an agarose gel. The gel was blotted and hybridizedto oligonucleotide α2. We used pEx2 as a primer for cDNA synthesis, and p0/BEpT for PCR to map mRNA from brain. OLUCI3 (synthesis of cDNA) and OLUCI2/BEpT (PCR) were used to map mRNA from transfected cells.
SLIC (Dumas Milnes Edwards et al., 1991). The cDNA was first synthesized from 5 μg total RNA using pEx3 (6 pmol) as a primer in 50 mM Tris-HCl pH 8.3;8 mM KCl; 1.6 mM MgCl 2 ; 5 mM spermidine; 0.5 mM dNTP; 1u/μl RNasin; 0.1 mg/ml BSA; 70 mM β-mercaptoethanol; 80 u AMV reverse transcriptase (Promega) at 42° for 45 minutes. The RNA was subsequently degraded in NaOH. The first strand of the cDNA was then ligated with the oligonucleotide A5′. The resulting single stranded CDNA was then submitted to two rounds of PCR amplification with oligonucleotides A5′-1/p0 and A5′-2/pl (35 cycles 94° C. 1 minute; 60° C. 30 seconds; 72° C. 45 seconds).
The sequence of the oligonucleotides were the following:
A5′: 5′-CTGCATCTATCTAATGCTCCTCTCGCTACCTGCTCACTCTGCGTGACAT(SEQ ID NO:4).
A5′: 5′-GATGTCACGCAGAGTGAGCAGGTAG (SEQ ID NO:5)
A5′: 5′-AGAGTGAGCAGGTAGCGAGAGGAG (SEQ ID NO:6)
p0: 5′ -CCAAAGCTGAACAGCAGCGCCATAG (SEQ ID NO:7)
p1: 5′-AGCAGCGCCATAGAGTTGGAGCACC (SEQ ID NO:8)
p2: 5′-AGGCGGCTGCGCGGCTTCAGCACCACGGAC SEQ ID NO:9)
pEx2: 5′-GCCGCTCCTCTGTGTCAGTACCCAAAACC (SEQ ID NO:10)
pEx3: 5′-ACATTGGTGGTCATGATCTG (SEQ ID NO:11)
BEpT: 5-GCGGGATCCGAATTC(T) 21 A/C/G (SEQ ID NO:12)
OLUCI3: 5′-CGAAGTATTCCGCGTACGTGATG (SEQ ID NO:13)
OLUCI2: 5′-ACCAGGGCGTATCTCTTCATAGC (SEQ ID NO:14)
Construction of Plasmids.
KS-Luci: The HindIII/KpnI restriction fragment of the pSVOAL plasmid (de Wet et al., 1987) was subcloned in the corresponding site of Bluescript KS. The most 5′ EcoRI/BsmI (45 bp) fragment of the Luciferase gene was then deleted according to (de Wet et al., 1987) and replaced by a Sal I site. The 342 bp PvuII/HindIII restriction fragment of SV40 containing the polyadenylation sites was subsequently subcloned into the EagI sites using adaptors.
EE1.2-Luci: The 1.2 kbp EcoRI/Eco47II fragment of the λβ2 phage was inserted in the EagI/SaII sites of KS-Luci using adaptors. The 5′ end deletions of the promoter were obtained using Bal3.1 exonuclease as in Current Protocols in Molecular Biology (Ausubel, et al., 1994).
The mutations were introduced using the Sculptor kit (Amersham). In the NRSE49 RE1 sequence, the mutated sequence was: +24 ACCACTTACA (SEQ ID NO:15) instead of ACCACGGACA, (SEQ ID NO:16) as this mutation was shown to reduce the activity of the NRSE element (Mori et al., 1992). In the E-box sequence the mutated sequence was: −120 TCCTCAGG (SEQ ID NO:17) instead of TCCACTTG (SEQ ID NO:18. FIG. 7 shows that a nuclear protein is able to bind to the wild type sequence, but not to the mutated sequence.
Transfection of Cells.
Neuroblastomas N1E115, human SK-N-Be, HeLa and 3T6 fibroblasts, 293 Human kidney cells and SVLT striatal cells (Evrard et al., 1990) were grown in DMEM +10% FCS supplemented with 1% glutamine and 1% streptomycin. PC12 cells were grown in DMEM +10% HS +5% FCS supplemented with 1% glutamine and 1% streptomycin.
Cells were plated at 10 5 to 4×10 5 cells/60 mm 2 plates. The next day cells were transfected in 750 μl of DMEM +2% Penicillin/Streptomycin for 5 to 12 hours with lgg DNA mixed with 2.5 μl of Transfectam (IBF/Sepracor) in 150 mM NaCl. The Luciferase activity was measured 48 hours later. DNA was prepared using Qiagen or Wizard prep (Promega) kits. When plasmid activities were compared, all plasmids were prepared the same day. At least two different DNA preparations were tested for each plasmid. All transfections were done in duplicate and repeated at least three times.
Production of Transgenic Mice.
The luciferase gene from EE1.2-Luci was excised and replaced by the nlsLacZ gene (Kalderon et al., 1984). The β2-promoter/nlsLacZ fragment was electroeluted from a TAE agarose gel then further purified by ethanol precipitation, and finally resuspended in Tris-HCl 10 mM pH 7.5; EDTA 0.1 mM. The DNA solution (3 ng/ml) was injected into fertilized oocytes of C57BL6xSJL hybrids. Staining of tissues was performed as described in Mercer et al., 1991.
See also the methods under FIG. 8 .
Gel Shift Assay
Oligonucleotides were labeled either with γ[ 32 P]ATP and T4 polynucleotide kinase, or with α[ 32 P]CTP and Klenow enzyme as in Current Protocols in Molecular Biology. Nuclear extracts were prepared from ≅10 7 cells as described (Bessis et al., 1993). For binding, 1 nmol of labeled oligonucleotide was mixed with 0,5 μg of protein extract in 10 mM Hepes pH 8, 10% glycero], 0,1 mM EDTA, 0,1 M NaCl, 2 mM DTT, 0,1 mg/ml BSA, 4 mM MgCl 2 , 4 mM spermidine, 1 mM PMSF, 1 μg polydIdC in 20 μl . The reaction was incubated for 10 minutes on ice. The DNA-protein complexes were then analyzed on a 7% polyacrylamide gel.
The oligonucleotides used in this experiments were double stranded with the following sequences (the underlined nucleotides are changed between the mutated and the wild type oligonucleotides):
E-D: 5′-TCCTCCCCTAGTAGTTCCACTTGTGTTCCCTAS (SEQ ID NO:19)
Liz Mut-E: 5′-CCTCCCCTAGTAGTTCCTCAGGTGTTCCCTAGA (SEQ ID NO:20)
S-E: 5′-CTAGCTCCGGGGCGGAGACTCCTCCC (SEQ ID NO:21) TAGTAGTTCCACTTGTGTTCCCTAG (SEQ ID NO:33)
Results
Characterization of the 5′ Flanking Sequences of the Gene Encoding the β2-subunit
A λ phage containing the gene encoding the β2-subunit was cloned and a region surrounding the initiator ATG was sequenced (FIG. 1 ). The transcription initiation site was first mapped by RNase protection (FIG. 2 A). This method allowed us to detect at least three initiation sites. However, minor additional start sites might not have been detected in these experiments. The size of the main protected band was estimated at about 150 nucleotides. To confirm and locate the initiation sites more precisely, we performed both RACE-PCR (Rapid Amplification of cDNA Ends; Frohman et al., 1988) and SLIC (Single Strand Ligation of cDNA; Dumas Milnes Edwards et al., 1991) which consist in the amplification of the primer extension product (FIG. 2 B). Both techniques allowed us to subclone and sequence the same fragments corresponding to the four initiation sites described in FIG. 1 . It is probable that the −13 start site is very rare and was not detected by RNase mapping.
Analysis of the sequence of the flanking region (FIG. 1) revealed several consensus DNA binding elements: an Sp1 site (−146), a cAMP responsive element binding (CREB) site (−287; Sassone-Corsi, 1988), a nuclear receptor response element (−344 to −356; Parker, 1993), a GATA-3 site (−1073; Ko and Engel, 1993), and a weakly degenerate Octamer motif (−522). Moreover, an E-box (−118) contained in a dyad symmetrical element could be recognized. The proximal region (−245 to +82) also has an unusually high GC content (67%) and a high number of dinucleotide CpG that may have some regulatory significance (Antequera and Bird, 1993). Finally, a 20 bp sequence identical to the NRSE * (Neural Restrictive Silencer Element; Mori et al., 1992) or RE1 (Restrictive Element; Kraner et al., 1992) sequence was found in the 3′ end of the 1.2 kbp fragment (+18 to +38).
A 1.2 kbp Fragment of Flanking Sequence of the β2-subunit Gene Promotes Neuron-Specific Expression in Vitro.
A construct was generated containing the 1163 bp EcoRI/Eco47III fragment (from −1125 to +38) of the β2-subunit 5′ flanking region fused to the Luciferase gene (de Wet et al., 1987) (plasmid EE1.2-Luci). The polyadenylation sites of SV40 were inserted upstream from the β2-subunit sequences to avoid readthrough. The transcriptional activity of the plasmid EE1.2-Luci was then tested by transient transfection into pheochromocytoma (PC12) cells, neuroblastoma cell lines NIE 115 and SK-N-Be, SVLT, a striatal cell line (Evrard et al., 1990), NIH3T6 or HeLa fibroblasts and human kidney cell line 293. Using RT-PCR, we verified that the neuroblastomas and the PC12 cells normally express the β2-subunit mRNA but not the striatal SVLT cell lines or the 3T6 fibroblasts. FIG. 3 shows that in PC12 cells and neuroblastomas, the 1.2 kbp fragment is 20 to 180-fold more active in mediating transcription of the reporter gene than in the other cell lines. In fibroblasts, 293 cells and SVLT cells, the transcriptional activity of the 1.2 kbp fragment is not significantly higher than that of the promoterless vector (FIG. 3 ). Therefore, the β2-subunit promoter is not active in these cell lines. These in vitro transfection experiments demonstrate that the 1163 bp fragment mimics the expression pattern of the endogenous β2-subunit gene, and thus contains a cell-specific promoter.
The 1163 bp Promoter in Transgenic Mice.
To test the 1163 bp promoter in vivo, the EcoRI/Eco47III fragment was linked upstream from the nls-o-galactosidase reporter gene (Kalderon et al., 1984). The polyadenylation signals from SV40 were ligated downstream of the coding sequences. The resulting 4.7 kb fragment was subsequently micro injected into the male pronuclei of fertilized eggs from F1 hybrid mice (C57B16xSJL). DNA extracted from the tails of the offspring was analyzed for the presence of the β-galactosidase gene by the polymerase chain reaction (PCR). Three independent founders were obtained and analyzed for expression. Two lines (13 and 26) had expression in neurons and the third line did not express at all. This shows that the 1163 bp promoter contains regulatory elements sufficient to drive neuron-specific expression in vivo. In the peripheral nervous system PNS, both lines expressed in the same structure. In contrast, in the CNS the labelling pattern of line 26 is a subset of that of line 13. We will only describe line 13 in detail. As expected, most peripheral β2-expressing ganglia expressed β-galactosidase (β-gal), whereas in the CNS only a subset of β2-positive regions expressed the β-gal. For instance, FIG. 4 C. shows that the vast majority of the neurons of the lumbo-sacral spinal cord express the β2-subunit transcripts, whereas only a subset of neurons in the ventral and dorsal horns display β-gal activity.
The expression of the transgene could be detected in the peripheral ganglia in E10.5 and E11 embryos. The labelling was examined in E13 total embryos (FIG. 4A) and in brains at later ages (E17, PO and adulthood). At E13, labelling was prominent in PNS: strong labelling was observed in the dorsal root ganglia (DRG, FIGS. 4 and 5C, D); some ganglia associated with the cranial nerves (the trigeminal see FIG. 5A, geniculate, glossopharyngeal and vagal ganglia); the ganglia of the sympathetic chain (FIG. 5C, D); the ganglionic cells of the retina (FIG. 5 A); and putative parasympathetic ganglia in the cardiac wall (FIG. 5 B). At E13, clusters of positive cells were also present at several levels of the neuraxis, in both the brainstem and the proencephalon. Clusters of stained neurons were also observed in the ventral and lateral spinal cord.
Later in development (E17), positive neurons were found clustered in several basal telencephalic nuclei whereas dispersed cells were stained in the caudate-putamen. At the diencephalic level, positive clusters were present in the zona incerta and reticular thalamic nucleus, and in many hypothalamic nuclei. In the brainstem, most motor nuclei of cranial nerves (with the exception of the dorsal motor nucleus of the vagus nerve) showed some to high labelling. In addition, the dispersed cells of the V mesencephalic nucleus appeared strongly stained, as well as the pontine nuclei, the prepositus hypoglossal nucleus and a few dispersed cells in the pontine tegmentum.
At PO in line 13, the distribution of positive cells already appeared more restricted than at previous ages (for example labelling in basal telencephalon and oculomotor nuclei was clearly diminished). In the CNS of adult animals labelled cells were detected only in the hypothalamus. In line 13, some clusters of cells were stained in the mucosa of the gastrointestinal tract (stomach and duodenum) and in the pancreas. Ectopic labelling was detected in the genital tubercle and in several superficial muscles of line 13, but none of these tissues were stained in the line 26.
Identification of a Minimal Cell Specific Promoter
To investigate in more detail the regulatory elements involved in the promoter activity, we generated a series of plasmids containing 5′ deletions of the 1163 bp promoter. These plasmids were tested by transient transfection into fibroblasts and SK-N-Be cells. These two cell lines were chosen as they were the most easily transfected cell lines. Moreover, the neuroblastoma line was initially isolated from peripheral structures (Biedler et al., 1978) and is a convenient tool to study the regulatory elements carried by the 1163 bp promoter.
When 157bp were deleted from the 5′ end of the 1163 bp promoter (plasmid 1006E-Luci, described in FIG. 1 ), the luciferase activity did not significantly change in neuroblastomas but increased in fibroblasts (FIG. 6 ). When 301 bp were further deleted, the activity of the remaining promoter continued to increase in the fibroblasts but not in neuroblastomas (see plasmid 862E-Luci, FIG. 6 ). Thus, the 157and 301 bp deleted plasmids carry repressor elements which are only active in fibroblasts. However, the truncated 862 bp promoter still displayed a neuron-specific activity (FIG. 6, compare activity of 862E-Luci in both cell lines), showing that additional regulatory elements are carried by the 1.2 kbp promoter. Moreover, a repressor could be present between −824 and −245 (compare the activities of 862E and 283E-Luci in the neuroblastomas). This putative regulatory element was not further analyzed. Indeed, a 283 bp promoter (plasmid 283E-Luci) is still ≅160 times more active in neuroblastomas than in-fibroblasts, confirming the presence of another neuron-specific regulatory elements in this proximal portion of the promoter.
When 150 bp were deleted from the 5′ end of the proximal 283 bp promoter, a very strong decrease of the transcriptional activity was detected in both fibroblasts and neuroblastomas (see of plasmid 133 E-Luci). This shows that crucial positive regulatory elements have been deleted. These positive and negative elements were further investigated by deletion and mutation studies of the proximal portion of the promoter.
Negative and Positive Regulatory Elements in the Proximal Region.
The 3′ end of the β2-subunit promoter contains putative protein factor binding sites. To analyze the role of these elements in β2-subunit gene regulation, we generated plasmids containing mutations in these binding sites. Using deletion experiments, an activator was detected between −95 and −245 (see FIG. 3, the difference between 283E and 133E-Luci). As the E-box located at nt-118 was a good candidate, we analyzed the effect of mutations in this element on transcriptional activity. Table 1A shows a 40% reduction of the transcriptional activity of the mutated promoter compared to that of the wild type promoter. The role of the E-box in non-neuronal tissues was more difficult to assess as the basal level of transcription was already low in fibroblasts.
To further understand the role of the E-Box in the regulation of the promoter, we investigated the protein complexes able to interact with this sequence. Gel shift assays were performed using the 33 bp sequence (nt-135 to −103, oligonucleotide E-D) as a probe. When the β 2 P labelled oligonucleotide was mixed with nuclear extracts from neuroblastomas or fibroblasts, three complexes were observed (FIG. 7 ). All of them were fully displaced by an excess of the unlabelled oligonucleotide E-D. In contrast, no competition was observed when the competitor oligonucleotide was mutated within the E-Box/Dyad (oligonucleotide Mut.E, see FIG. 7 lane “Mut-E”). This shows that the E-box/Dyad is the only element contained within the −135/103 sequence able to bind nuclear protein. This sequence is likely to be involved in the activity of the β-subunit promoter.
An NRSE/RE1 sequence is also present in the proximal region and has been shown to act as a silencer in fibroblasts but not in PC12 cells or neuroblastomas (Kraner et al., 1992; Li et al., 1993; Mori et al., 1992). Point mutation of this sequence in the context of the 1163 bp promoter resulted in a 105-fold increase in the transcriptional activity in fibroblasts, and only a 3-fold increase in neuroblastomas (Table 1A). This sequence is thus responsible for at least part of the cell-specific expression of the β2 subunit gene.
TABLE 1
A
Fibroblasts (3T6)
Neuroblastomas (SK-N-Be)
EE1.2-Luci wild type
1.1
(100%)
157
(100%)
EE1.2-Luci/NRSE/RE1
115.5 ± 13.8
(1050%)
502 ± 204
(320%)
EE1.2-Luci/E-Box
ND
94 ± 14
(60%)
B
Mouse β2
TGCGCGGC.TTCAGCACCACGGACAGCGC.TCCCGTCC
Sodium Channel (nt 29)
ATTGGGTT.TTCAG A ACCACGGACACC A C.CAGAGTCT
SCG10 (nt 621)
AAAGCCAT.TTCAGCACCACGGA G AG T GC.CTCTGCTT
Synapsin I (nt 2070)
CTGCCAGC.TTCAGCACCGCGGACAG T GC.CTTCGCCC
CAML1 (nt 1535)
TACAGGCC.T C CAGCACCACGGACAGC AG .ACCGTGAA
Calbindin (nt 1093)
CCGAACGG. AG CAGCACC G CGGACAGCGC.CCCGCCGC
Neurofilament (nt 383)
ATCGGGGT.TTCAGCACCACGGACAGC T C.CCGCGGGG
TTCAGCACCACGGACAGCGC
Table 1: Positive and negative regulatory elements in the proximal region of the 1163 bp promoter.
In Table 1, Mouse P2 is SEQ ID NO:23, Sodium Channel (nt29) is SEQ ID NO:24, SC G10 (nt621) is SEQ ID NO:25, Synapsin I (nt2070) is SEQ ID NO:26, CAML1 (nt1535) is SEQ ID NO:27, Calbindin (nt1093) is SEQ ID NO:28, Neurofilament (nt383) is SEQ ID NO:29, and the final sequence is SEQ ID NO:34.
A. Effect of mutations in the proximal part of the 1163 bp promoter. The activities of the wild type or mutated promoters are normalized to the luciferase activity of the promoterless KS-Luci plasmid. The activities of EE1.2-Luci are from FIG. 3 .
B. Alignment of the proximil silencer of the β-subunit promoter with other neuronal promoters. The sequences are taken from (Maue et al., 1990, Na channel, accession number M31433), (Mori et al., 1990; SCG10, M90489), (Sauerwald et al., 1990; Synapsin I, M55301), (Kohn et al., 1992; CAML1 gene, X63509), (Gill and Christakos, 1993, Calbindin gene, L11891), (Zopf et al., 1990; Neurofilament gene, X17102, reverse orientation). The numbering refers to the sequences in the GenBank/EMBL library.
Elimination of High Affinity Nicotine Receptor in Transgenic Mice Results in Alteration of Avoidance Learning
The β2-subunit of the nAChR was disrupted in embryonic stem (ES) cells, and mice deficient in this subunit were subsequently generated (FIG. 8 ). β2−/−-mice were viable, mated normally and showed no obvious physical deficits. Overall brain size and organization were normal (see for example FIGS. 9, A and B). Western blot analysis-of total brain homogenates using anti-β2 monoclonal 270 11 (FIG. 8 d ) and immunocytochemistry throughout the brain using a polyclonal anti-β2 antibody 9 demonstrated that the immunoreactivity detected in control mice was absent in β2−/−mice and was diminished in β+/+mice. β2-encoding mRNA was undetectable in β2−/−mice by in situ hybridization using β2-antisense oligonucleotides (FIG. 9 A).
The distributions of the α4- and β2-subunits largely overlap in the brain, and these subunits are thought to combine to form the predominant nAChR isoform in the CNS 12 . Based on oocyte expression experiments 4 , β4-is the only subunit identified thus far that might also be able to form functional heteropentamers with the α4-subunit. The β4-subunit was expressed normally in the brains of β2+/−mice or β2−/−mice, with expression in the medial habenula (MHb) and the interpeduncular nucleus (IPN) 10 , and no up regulation elsewhere in the brain to replace the β2-subunit (FIG. 9 A). Nor was the expression of the α4- (FIG. 9 A), α5- or 3-subunit mRNAs significantly altered in mutant mice.
Equilibrium binding experiments have shown that nicotine binds to a population of high affinity sites (KD near 10 nM 13, 14 ) whose distribution tallies well with that of the α4- and 2-subunits 13-15 . Quantitative receptor autoradiography was performed using 3 H-nicotine (4 nM) to visualize high affinity nAChR in brain sections from β2+/+, +/− and −/−mice (FIG. 9 B). Nicotine binding in situ was completely abolished in )2−/−animals, and was reduced by approximately 50% in all brain areas in β2+/−animals implicating the β2-subunit in mediating this high affinity binding.
Electrophysiology of Transgenic Mice.
Neurons of the anterior thalamus, which express very high levels of β2 (and α4) subunit mRNAs (FIG. 9 A), were studied for an electrophysiological response to nicotine. This area, easily accessible in a slice preparation, responded consistently to 10 μM nicotine in wild type animals with an average inward current of 155+/−73 pA which was blocked by 1 μM dihydro-β-erythroidine. The agonist order of the response was compatible with that seen for α4/β2-containing nicotinic receptors in vitro 6 (nicotine>DMPP>cytisine) (FIG. 10 A). Anterior thalamic neurons required several minutes to an hour for complete recovery of the agonist response, suggesting that receptor response is prone to desensitization. Moreover, a relatively high dose of 1 μM was required for a reproducible response, implying that nicotine does not bind to its high affinity site to activate. High affinity nicotine binding sites may therefore be nAChRs in a desensitized conformation.
In β2−/−mice the response of anterior thalamic neurons to nicotine was completely abolished in 100% of neurons tested (FIG. 10 B). As a control, neurons in the MHb, where both α3 and β4 are strongly expressed, were also tested. Nicotine caused an average inward current of 505+/−132 pA in wild type mice, and the agonist potency of this response followed the rank order for the α3/β4 containing receptor (cytisine=nicotine>DMPP) (FIG. 10 A). As expected, the response of cells in the MHb to nicotine was maintained in mutant mice.
The 62 subunit is expressed in the ganglia of wild type animals 8-10 , but there was no apparent difference in heart rate or basal body temperature. Spontaneous locomotor activity, which is sensitive to high doses of nicotine and is not modified by drugs selective for the β2/α4 isoform of the nAChR 16 was not significantly different in β2−/−, β+/1 and β+/+mice.
Cognitive and Behavioral Results.
Learning and memory were examined in mutant and wild type mice using two procedures. The Morris water maze 17,18 evaluates spatial orientation learning. The performance of mutant mice on this test did not differ from that of wild type mice when tested on the visible platform task, or on the hidden platform task (minimum swim-time reached after 5 days of training: mutants (n=8): 7.4+/−1.4 sec; wild type (n=8): 8.2 +/− 2.0 sec). In the transfer test both groups of animals spent approximately 35% of the time in the platform quadrant, with the same number of platform crossings (mutants: 4+/−0.4; wild type: 3.9+/−0.6).
Retention of an inhibitory avoidance response was assessed using the passive avoidance test, which was also chosen for its pharmacological sensitivity to nicotine administration 19,20 . This test consisted of a training trial in which the mouse was placed in a well-lighted chamber of a shuttle box, and the latency to enter the adjacent dark chamber was measured. Upon entry to the dark chamber, a mild, inescapable foot shock was delivered, and vehicle or nicotine (10 μg/kg) was injected into the mouse. Twenty-four (24) hours later, retention was assessed by measuring the latency to enter the dark chamber. Time spent in the light chamber (retention latency) increased proportionally to the applied foot shock in both mutant and wild type mice. However, treatment with nicotine consistently facilitated retention (p<0.01) by shifting the curve upward by approximately 80 sec only in wild type mice (FIG. 10 A). Nicotine administration was completely ineffective in mutant mice. Interestingly, retention latency was significantly higher for mutant mice than for their non-mutant, vehicle-injected siblings (p<0.05) (FIG. 10 B).
Increased retention in the passive avoidance test can be observed in animals with a decreased pain threshold or increased emotionality. Therefore, further behavioral testing was performed on all mice included in this experiment. Mutant mice did not differ from their non-mutant siblings for flinch, vocalization or jump response to foot shock. Emotionality was tested by measuring exploratory activity in a two compartment apparatus for 15 min 21,22 . The average time spent in the dark compartment, the locomotor activity in the dark compartment and the transitions between compartments did not differ between the mutant and wild type mice. Therefore, neither changes in pain sensitivity nor changes in emotionality can account for the difference in retention latency observed in passive avoidance testing.
Studies using low doses of nicotine 23 or specific nicotinic agonists 16 suggest that high affinity nAChRs in the brain mediate the effects of nicotine on passive avoidance. Accordingly, nicotine cannot change the performance of β2−/−mice on this test, as they lack high affinity binding sites. The enhanced performance of mutant mice versus wild type mice is quite surprising, however. Several explanations for the paradoxical effect of the β2-subunit mutation can be proposed. One hypothesis is that nicotine injection improves performance of wild type mice on passive avoidance as a result of desensitization, and thus inactivation of nAChRs, leading to enhanced performance on the test. Therefore, the behavior of mice lacking the receptor might mimic that of mice whose receptors have been desensitized 24 . Another possibility is that nAChRs may be present in at least two pathways that interact with opposite effects to generate the behavior measured in passive avoidance. If one pathway is physiologically more active than the other, the inactive pathway will be preferentially stimulated by injection of nicotine in wild type animals, while the more active pathway will be preferentially influenced by β2-gene inactivation.
The experiments described above demonstrate that nAChRs containing the β-subunit mediate the effects of nicotine on passive avoidance, a specific learning task. These mice provide a model system for studying the pharmacological effects of nicotine in the CNS, and are useful in elucidating the role of high affinity nAChRs in cognitive processes, nicotine addiction, and dementias involving deficits of the nicotinic system.
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Le Mouellic, H., Brullet, P., WO 90/11354
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33
45 base pairs
nucleic acid
single
linear
DNA (genomic)
1
TCGCATGTGG TCCGCAATGA AGCGTACGCC ATCCACTGCT TCCCG 45
45 base pairs
nucleic acid
single
linear
DNA (genomic)
2
CCTTCTCAAC CTCTGATGTC TTCAAGTCAG GGACCTCAAG GGGGG 45
45 base pairs
nucleic acid
single
linear
DNA (genomic)
3
ACCAGGCTGA CTTCAAGACC GGGACGCTTC ATGAAGAGGA AGGTG 45
50 base pairs
nucleic acid
single
linear
DNA (genomic)
4
CTGCATCTAT CTAATGCTCC TCTCGCTACC TGCTCACTCT GCGTGACATC 50
25 base pairs
nucleic acid
single
linear
DNA (genomic)
5
GATGTCACGC AGAGTGAGCA GGTAG 25
24 base pairs
nucleic acid
single
linear
DNA (genomic)
6
AGAGTGAGCA GGTAGCGAGA GGAG 24
25 base pairs
nucleic acid
single
linear
DNA (genomic)
7
CCAAAGCTGA ACAGCAGCGC CATAG 25
25 base pairs
nucleic acid
single
linear
DNA (genomic)
8
AGCAGCGCCA TAGAGTTGGA GCACC 25
30 base pairs
nucleic acid
single
linear
DNA (genomic)
9
AGGCGGCTGC GCGGCTTCAG CACCACGGAC 30
30 base pairs
nucleic acid
single
linear
DNA (genomic)
10
GCCGCTCCTC TGTGTCAGTA CCCAAAACCC 30
20 base pairs
nucleic acid
single
linear
DNA (genomic)
11
ACATTGGTGG TCATGATCTG 20
37 base pairs
nucleic acid
single
linear
DNA (genomic)
12
GCGGGATCCG AATTCTTTTT TTTTTTTTTT TTTTTTV 37
23 base pairs
nucleic acid
single
linear
DNA (genomic)
13
CGAAGTATTC CGCGTACGTG ATG 23
23 base pairs
nucleic acid
single
linear
DNA (genomic)
14
ACCAGGGCGT ATCTCTTCAT AGC 23
10 base pairs
nucleic acid
double
linear
DNA (genomic)
15
ACCACTTACA 10
10 base pairs
nucleic acid
double
linear
DNA (genomic)
16
ACCACGGACA 10
8 base pairs
nucleic acid
double
linear
DNA (genomic)
17
TCCTCAGG 8
8 base pairs
nucleic acid
double
linear
DNA (genomic)
18
TCCACTTG 8
33 base pairs
nucleic acid
single
linear
DNA (genomic)
19
TCCTCCCCTA GTAGTTCCAC TTGTGTTCCC TAG 33
33 base pairs
nucleic acid
single
linear
DNA (genomic)
20
CCTCCCCTAG TAGTTCCTCA GGTGTTCCCT AGA 33
52 base pairs
nucleic acid
single
linear
DNA (genomic)
21
CTAGCTCCGG GGCGGAGACT CCTCCCCTAG TAGTTCCACT TGTGTTCCCT AG 52
1289 base pairs
nucleic acid
double
linear
DNA (genomic)
22
GGAATTCCTG AAAACACTCA AGTTTAAGTA AAAGGTAGGT AGGGGCACTG GGGTGATAAA 60
AGAGCTGGAG GGAACTACAT GTTTAAAAGA CCGAGGGCTA GGAGGGGTTA AATAGTCAAG 120
GATCTTAAAG ACGTCGTCAA TAGCTAGAAT GTGGAGCTGA GACAGGCATT GACGAGATGA 180
AGTCCGAAGC CTTTTGTCTG CTAAGTCTGC TTCAGACAGA AATCTTTTTG GTTGAAAGTG 240
ACCACTGATC CACTAAGAAA AAAAAAGAGG TCCTTTTTGG GCTCAGTAGC TAAAACGGCA 300
GGGCTTTCAA GATCAAACAT GTCATTGAGT TTTGACACCT CTCTCATCTT TGCTCTCTTT 360
GTGTTAGCTT CATTCTTTCT GTGAAATGGT CCCCTGATCT CCCCAGAACA CAGCGTGGAA 420
GGAACCATTG ATATTGGTTG CTTATGCAGA TCTCAGAACT TTCAAGGCCA CCTTCTTTTC 480
AGGAGGTCTA GACCTATCTA GCTTAGATTC CCCAGGAGAA TGGCAAGATC TTGGCCTTGT 540
CTGAGCTTAT GGAAGCAGAG AAGGGGGCAG GTGCAAAAGA CTCTCTTCCA GAACTCCGGA 600
GAAATTTGCT TTTCAAAACT AGACAGCACC CTGCTGCCTA CTAAAGAAGT AGGTCCAAGG 660
TCCTAATGTG CATATTCTCC GCTATACTCT TAGCTTTCCA GAAAACTAGA ATCATCAGTT 720
TGGGTAAGAA CATAGAGGAA AACAGAAACG CCCCCCAACC TACCCCATGT CCAGAGAGCC 780
TTGACCTACT TGTCTCCCTC CCACTCTCAA CCCTCCCAGT CTTGCTTCAA ACCTCTCCAC 840
GTCATGCCCC AACTTCGGAG CATTTGAACT CTGAGCAGTG GGGTCGCTTT CGCCTCAAGC 900
ACACCCCACC TCGGCAGGCC CAGTCAAAGG TCCCTCACAG GGACACCTTT TTTTCCCTGG 960
GATCCCGCGC TTCGCCTCCG GGGCGGAGAC TCCTCCCCTA GTAGTTCCAC TTGTGTTCCC 1020
TAGAAGAGCA GCCGGGACGG CAAGAAGCCG GGACCTCCCC CTTCGTTCCA GGAACTGCCG 1080
CGCAGTGGGC ACTTCAGCCC TGGAGGCCGC GAGCCCCACC CGGGTGAAGG CGGCTGCGCG 1140
GCTTCAGCAC CACGGACAGC GCTCCCGTCC GCAGCCCTTG TGTCAGCGAG CGTCCGCGCT 1200
CGCGCTATGC AGGCGCATGG CCCGGTGCTC CAACTCTATG GCGCTGCTGT TCAGCTTTGG 1260
CCTCCTTTGG CTGTGTTCAG GTAAGAATT 1289
36 base pairs
nucleic acid
single
linear
DNA (genomic)
23
TGCGCGGCTT CAGCACCACG GACAGCGCTC CCGTCC 36
36 base pairs
nucleic acid
single
linear
DNA (genomic)
24
ATTGGGTTTT CAGAACCACG GACAGCACCA GAGTCT 36
36 base pairs
nucleic acid
single
linear
DNA (genomic)
25
AAAGCCATTT CAGCACCACG GAGAGTGCCT CTGCTT 36
36 base pairs
nucleic acid
single
linear
DNA (genomic)
26
CTGCCAGCTT CAGCACCGCG GACAGTGCCT TCGCCC 36
36 base pairs
nucleic acid
single
linear
DNA (genomic)
27
TACAGGCCTC CAGCACCACG GACAGCAGAC CGTGAA 36
36 base pairs
nucleic acid
single
linear
DNA (genomic)
28
CCGAACGGAG CAGCACCGCG GACAGCGCCC CGCCGC 36
36 base pairs
nucleic acid
single
linear
DNA (genomic)
29
ATCGGGGTTT CAGCACCACG GACAGCTCCC GCGGGG 36
72 base pairs
nucleic acid
single
linear
DNA (genomic)
30
GTCGACGGTA CCGCCCGGGC AGGCCTGCTA GCTTAATTAA GCGGCCGCCT CGAGGGGCCC 60
ATGCATGGAT CC 72
25 base pairs
nucleic acid
single
linear
DNA (genomic)
31
GCCCAGACAT AGGTCACATG ATGGT 25
26 base pairs
nucleic acid
single
linear
DNA (genomic)
32
GTTTATTGCA GCTTATAATG GTTACA 26
20 base pairs
nucleic acid
single
linear
DNA (genomic)
33
TTCAGCACCA CGGACAGCGC 20 | Several genes encoding subunits of the neuronal nicotinic acetylcholine receptors have been cloned and regulatory elements involved in the transcription of the α:2 and α:7 subunit genes have been described. Yet, the detailed mechanisms governing the neuron-specific transcription and the spatio-temporal expression pattern of these genes remain largely uninvestigated. The β2-subunit is the most widely expressed neuronal nicotinic receptor subunit in the nervous system. We have studied the structural and regulatory properties of the 5′ sequence of this gene. A fragment of 1163 bp of upstream sequence is sufficient to drive the cell-specific transcription of a reporter gene in both transient transfection assays and in transgenic mice. Deletion analysis and site-directed mutagenesis of this promoter reveal two negative elements and one positive element. The positively acting sequence includes one functional E-box. One of the repressor elements is located in the transcribed region and is the NRSE/RE1 sequence already described in promoters of neuronal genes. | 0 |
BACKGROUND OF THE INVENTION
[0001] Roller-type retractable window shades have long been used to provide shade and privacy for the interiors of buildings and automobiles. A multitude of different window widths is a problem that has plagued the designers of these window shades. One approach to solving this problem is to construct a wide range of different fixed-width window shades, such that a different fixed-width window shade is available for every different window width. Of course, this approach to the problem results in a very large inventory of fixed-width shades, and prevents using the same window shade with windows of different width.
[0002] To avoid having to construct a different fixed-width shade for each different window width, attempts have been made to construct adjustable-width window shades. In particular, “cut-to-fit” window shades have been constructed that permit easy width modification at the site of installation. However, once cut to a desired size, these window shades can no longer be expanded to their original maximum width. Thus, these configurations only provide a partial solution to the problem. In particular, these “cut-to-fit” window shades are not truly “adjustable-width” in that they are not repeatedly width-adjustable within their original range of width adjustment. Moreover, adjustable-width roller shades, which are specifically configured for deployment in automobiles, are not commercially available at present.
[0003] It is believed that the present unavailability of truly adjustable-width widow shades results from the inability of roller shade designers to solve the problem of mounting overlapping shade sheets on a roller that telescopes to provide width adjustment. A second unsolved problem is to design a telescoping shade that maintains “proper orthogonal tracking” at all available widths within the shade's range of width adjustment. Generally, “proper orthogonal tracking” is the ability of the shade to remain sufficiently perpendicular to the roller, as the shade winds onto the roller, to prevent an unacceptable amount of movement of the shade along the roller. In other words, proper orthogonal tracking allows the shade to wind on top of itself as it winds onto the roller, in order to prevent the shade from traveling along the length of the roller, as the shade repetitively wraps around the roller. In general, partial overlapping of the shade material being wound around the roller results in a varying thickness of the shade material along the length of the roller, prevents proper orthogonal tracking and causes the shade to move along the roller with subsequent turns of the shade around the roller. When this occurs, the window shade may form a cone rather than a cylinder as it winds, and thus bind or become damaged during retraction.
[0004] Accordingly, a need exists in the art for an improved adjustable-width window shade that is repeatedly width-adjustable within its original range of width adjustment. There is a further need for an adjustable-width roller shade that is specifically configured for deployment in automobiles. And there is a further need for an adjustable-width roller shade that maintains proper orthogonal tracking within the shade's range of width adjustment.
SUMMARY OF THE INVENTION
[0005] The present invention meets the needs described above in an adjustable-width roller shade that maintains proper orthogonal tracking at all available widths within the shade's range of width adjustment. More particularly, the adjustable-width roller shade utilizes two overlapping window shades and a telescoping roller to provide a shade that is repeatedly width-adjustable within its original range of width adjustment. To keep the shade sufficiently perpendicular to the roller as the shade winds onto the roller, orthogonal tracking spacers, such as strips of pliable material attached to non-overlapped portions of the shade material, compensate for the extra layers existing at the overlapped portion of the shades. Thus, the roller shade maintains proper orthogonal tracking of the shade at all available widths within the shade's range of width adjustment.
[0006] This configuration of the window shade allows the same shade to be adjusted to fit many different windows without having to cut or otherwise permanently alter the window shade. For this reason, multiple window shades may be adjusted, as desired, and placed side-by-side to fit curving and odd-shaped windows, such as automobile windshields and rear windows. Of course, the same roller shade may be used for side windows as well. Thus, the same window shade may be easily and cost effectively deployed to fit most of the windows of every different automobile make and model on the road, without having to cut or otherwise permanently alter the window shades. It is expected that this advantage will result in a far greater deployment of automobiles window shades than prior window shades have been able to accomplish.
[0007] In addition, the outer facing surfaces of the window shades provide advertising space that is visible to the public when the shades are pulled down inside parked automobiles. Thus, making the window shades more attractive to a substantial portion of automobile owners has the associated benefit of deploying millions of square feet of advertising space. Accordingly, automobiles including these window shades, with and without advertising indicia printed on the outward facing surfaces of the shades, are considered to be within the scope of the present invention.
[0008] Generally described, the present invention is an adjustable-width roller shade including a telescoping roller assembly having an adjustable width. The telescoping roller assembly is characterized by a shade mounting system that allows free telescoping of the roller assembly. The telescoping roller assembly carries a telescoping shade assembly that varies in width in cooperation with changes in the width of the telescoping roller assembly. The telescoping shade assembly is characterized by two shades with inner portions that overlap each other by an amount that varies with the width of the telescoping shade assembly. In addition, each shade defines an outer portion located away from the overlapped inner portion of the corresponding shade. To provide proper orthogonal tracking of the shades onto the roller, the outer portion of each shade carries an orthogonal tracking spacer, such as a strip of pliable material attached along the edge of the sheet with a thickness selected to compensate for the overlapped condition of the inner portion of the corresponding shade as that shade winds around the roller assembly. The shade also includes a spring motor, which is coupled to the roller assembly that operates to store spring energy as the shades are moved from a rolled-in configuration to a rolled-out configuration. This spring motor also uses stored spring energy to move the shades from the rolled-out configuration to the rolled-in configuration.
[0009] The roller shade may also include written indicia carried on at least one of the first and second shades that is available for viewing when the shades are in a substantially rolled-out configuration. In particular, the invention may include an automobile having a front windshield of substantial width and carrying multiple roller shades positioned in side-by-side relation across the width of the front windshield. In addition, the invention may include an automobile having a rear window of substantial width and carrying multiple roller shade positioned in side-by-side relation across the width of the rear window.
[0010] More specifically described, the telescoping roller assembly may include an inner roller having an outer longitudinal surface defining a cylinder with a longitudinal ridge extending radially outward from the cylinder. The telescoping roller assembly may also include an outer roller having an outer longitudinal surface defining a cylinder with a longitudinal channel cut through a substantial portion of the longitudinal extent of the outer surface. In addition, the inner roller is concentrically received within the outer roller, with the ridge positioned within the channel, to form a telescoping roller assembly of adjustable width. Typically, the first shade is attached to the ridge of the inner roller, and the second shade is connected to the outer surface of the outer roller.
[0011] The roller shade may also include a telescoping outer cover housing the roller assembly and constraining the spring motor from unintended release of stored spring energy. In this case, the first and second shades pass through an opening in the cover as the shades move between a fully rolled-in configuration and a substantially rolled-out configuration.
[0012] The roller shade may also include a first rod carried by a free edge of the first shade, a second rod carried by a free edge of the second shade; and a clip for securing the first and second rods together after the roller shade has been adjusted to a desired width. In this case, roller shade may also include a hook coupled to at least one of the first and second shades, typically at the clip, for securing the shades in a substantially rolled-out configuration.
[0013] In view of the foregoing, it will be appreciated that the adjustable-width roller shade avoids the drawbacks of conventional roller shades, including those configured for “cut-to-fit” width adjustment. The specific techniques and structures employed by the invention to improve over the drawbacks of the prior roller shades and accomplish the advantages described above will become apparent from the following detailed description of the embodiments of the invention and the appended drawings and claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] [0014]FIG. 1 is an exploded, perspective view of an adjustable-width window shade made in accordance with the present invention.
[0015] [0015]FIG. 2 is a perspective view of the adjustable-width window shade.
[0016] [0016]FIG. 3 is a perspective view of an automobile with its windshield protected by two adjustable-width window shades positioned side by side.
[0017] [0017]FIG. 4 is a perspective view of the receiving end of the second roller tube.
[0018] [0018]FIG. 5 is a perspective view of the inner end of the first roller tube.
[0019] [0019]FIG. 6 is an exploded, perspective view of an attached clip assembly.
[0020] [0020]FIG. 7 is a perspective view of the cap end of the second roller tube.
[0021] [0021]FIG. 8 is a perspective view of the cap end of the first roller tube with the short collar in place.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0022] The invention may be deployed as a retractable, spring-operated, horizontally-mounted, adjustable-width window shade that can be adjusted and readjusted in width without tools, training or trimming, to provide an adjustable width window shade that maintains accurate orthogonal tracking at any allowable width. This window shade typically includes a structurally integrated cover tube that protects the shade material when not in use, provides mounting points for attachment to a window, and prevents the spring motor from unwinding prior to installation. The window shade can be advantageously shipped and stored in its relatively small fully-retracted size and, once received by the customer, it may be quickly and easily adjusted to a desired width and installed by automobile technician or end user.
[0023] It should be appreciated that, although the preferred embodiment of the invention is described as a retractable, spring-operated, horizontally mounted window shade, many other window shade configurations may be constructed using the principles of the present invention. For example, roller-to-roller shades, rather than a telescoping single-roller retractable shade, may be constructed. Similarly, hand-crank or motorized shades, rather than a spring-operated shade, may be constructed. Further, vertically or angularly mounted shades, rather than a horizontally mounted shade, may be constructed. Many other modifications and variations of the invention described herein, which will become obvious to those skilled in the art, are within the spirit and scope of the present invention.
[0024] The invention may also be used for shades or covers other than window shades. For example, the invention may be deployed in an adjustable-width projector screen, an adjustable-width fish tank screen or cover, or an adjustable-width cover for an interior room opening, such as those commonly located between a kitchen and a living room. Many other applications for the invention described herein, which will become obvious to those skilled in the art, are within the spirit and scope of the present invention.
[0025] In a preferred embodiment, the retractable, spring-operated, horizontally-mounted, adjustable-width window shade comprises a first assembly, a second assembly, a telescoping housing or cover tube, and a retaining hook. The first and second assemblies may each be based on one half of a hollow two piece roller tube designed to telescope.
[0026] The first assembly begins with that half of the telescoping roller tube with the smaller outside diameter. Attached to one side of this first roller tube, along its entire length, is a narrow, rectangular shaped ridge. This first roller tube ridge is of sufficient height, or thickness, so as to match the wall thickness of the second, larger diameter, section of the telescoping roller tube. This first assembly roller tube also has a short collar mounted on the outer tube end. This collar is slotted along its length to matingly engage the rectangular first roller tube ridge. This short collar has an outer circumference that matches the outer circumference of the larger diameter second roller tube. A pliable first sheet of shade material is attached by its leading or top horizontal edge to the top of the first roller tube ridge. This first shade sheet is as wide as the first roller tube is long. A first orthogonal tracking spacer, such as a strip of pliable material, is attached on the inner surface adjacent to the outer vertical edge of the first shade sheet. This spacer is attached a predetermined distance from the top horizontal or mounting edge and runs to the bottom horizontal edge. This first orthogonal tracking strip is as wide as the first roller tube short collar and as thick as the second shade sheet. A square stiffening rod is attached along the entire length of the bottom or trailing horizontal edge on the inner surface of the first shade sheet. This stiffener rod extends a predetermined length beyond the inner vertical edge of the first shade sheet.
[0027] The second assembly begins with that half of the telescoping roller tube with the larger outside diameter. This second roller tube has an inner circumference sufficient to matingly engage the outer diameter of the first roller tube. This second roller tube is longer than the first roller tube by a predetermined amount and has a narrow channel along one side to matingly engage the first roller tube ridge. This channel is long enough to accept that length of the first roller tube ridge not covered by the first roller tube collar. The outer circumference of the second roller tube is sufficient so that when the first roller tube is fully inserted into the second roller tube the outer surfaces of the first roller tube ridge and the first roller tube short collar are approximately flush with the outer circumference of the second roller tube. A pliable second sheet of shade material is attached by its leading edge to the second roller tube at a point in advance of the second roller tube channel. The width of this second shade sheet is equal to the second roller tube length. Another orthogonal tracking spacer is attached to the inside face of the second shade sheet along the entire outer vertical edge. This second orthogonal tracking spacer, again a pliable strip of material, is as thick as the first shade sheet and as wide as the first shade sheet orthogonal tracking strip. A second square stiffening rod is attached to the outer face of the second shade sheet along the entire length of the bottom or trailing horizontal edge.
[0028] The orthogonal tracking spacer may be a strip constructed from a relatively thin, continuous strip of the same material from which the sheet is constructed. However, it should be appreciated that the orthogonal tracking strip may be constructed from any other type of pliable material having the desired flexibility. In addition, structures other than a thin, continuous strip of pliable material may be used as the orthogonal tracking spacer. For example, one or more strips of thin, flat wire could be attached to the sheet material. Rather than being continuous, the tracking spacer may be intermittent, such as a series of patches or plastic tabs spaced along the edge of the sheet. That is, any type of structure configured to maintain acceptable orthogonal tracking by offsetting the overlapped thickness of the sheets at the center of the roller will function properly as an orthogonal tracking spacer. Nevertheless, a continuous orthogonal tracking strip attached along the outer edge of each sheet, which is constructed from a relatively thin, continuous strip of the same material from which the sheet is constructed, has been found to be the most convenient, effective and technically successful structure for implementing the orthogonal tracking spacer.
[0029] With the first roller tube inserted into the second roller tube, the second shade sheet overlaps and slidably engages the first shade sheet. During the rolling process the second shade sheet is rolled upon the inner edge of the first shade sheet and the second orthogonal tracking spacer. During winding, the orthogonal tracking spacer attached to the second shade sheet continuously adjusts the circumference of the outer end of the second roller tube to match the change in circumference occurring on the inner end of the second roller tube where the two shade sheets overlap.
[0030] The first shade sheet is rolled upon the inner end of the second roller tube and the first roller tube short collar for the first full revolution. At the beginning of the second revolution the first shade sheet begins to be wound on top of, or overlap, the first layer of the inner edge of the second shade sheet. At this point, the first shade sheet orthogonal tracking spacer begins adjusting the circumference of the first roller tube outer end to match the change in circumference occurring on the inner end of the second spin tube where the two shade sheets overlap. This allows each sheet to maintain proper orthogonal tracking as it winds onto the roller. True telescoping ability is achieved by utilizing the ridge and channel so that the sheet mounted onto the first roller tube does not interfere with the telescoping action. This roller system, in combination with the orthogonal tracking strips, establishes telescoping ability and maintains orthogonal tracking at any available width of the adjustable-width roller.
[0031] The roller and shade assembly is typically housed within a cover tube that includes two sections designed to telescope freely while resisting any rotational movement, allows free extension and retraction of the two shade sheets, prevents stored spring energy in the roller assembly from unwinding, and provides convenient attachment points for attaching the shade to a window.
[0032] Referring now to the drawings, in which like reference numerals designate corresponding parts throughout the several figures, reference is made first to FIG. 1, which shows an exploded and perspective view of an adjustable-width window shade 10 . The shade 10 comprises a first assembly 20 , a second assembly 40 , a housing 60 , and a retaining hook 70 .
[0033] Referring to FIG. 1, the first assembly 20 has an elongated, cylindrically shaped first spin tube 21 having a cap end 22 , a mating end 23 , a first tube longitudinal axis extending between the cap and mating ends 22 and 23 , a first bore 24 , a first surface 25 , and a ridge 26 extending outwardly from the first surface 25 and being substantially parallel to the first tube longitudinal axis. A first sheet 27 having a first upper edge 27 a and a first lower edge 27 b, a first inner edge 27 c, and a first outer edge 27 d, is mounted to the ridge 26 proximate the first upper edge 27 a. Attached proximate the first outer edge 27 d is an orthogonal tracking spacer 13 and proximate the first lower edge 27 b is a rib 64 a. Mounted to the first spin tube 21 proximate the cap end 22 is a short collar 29 . The short collar 29 has a collar groove 30 , which matingly engages the ridge 26 , and a collar surface 31 . Preferably, the short collar surface 31 is substantially flush with the outer most portion of the ridge 26 . Disposed within the first bore 24 at the cap end 22 is a bushing 32 and axle 33 that is threaded at one end to facilitate attachment of a first cap 36 and a mounting bracket 37 . A first rod 33 having a first threaded end 34 is inserted into and rotatably engages the first busing 32 . Disposed over the first threaded end 34 is a first washer 35 and a first cap 36 . The first threaded end 34 extends through and beyond the first cap 36 . A mounting bracket 37 is placed onto the first threaded end 34 and secured to the first rod 33 and the first cap 36 by a nut 38 .
[0034] Again referring to FIG. 1, the second assembly 40 has an elongated, cylindrically shaped second spin tube 41 having a cap end 42 , a receiving end 43 , a second tube longitudinal axis extending between the cap and receiving ends 42 and 43 , a second bore 44 extending therethrough, and a channel 45 extending a predetermined distance substantially parallel to the second tube longitudinal axis from the receiving end 43 toward the mount end 42 . The channel 45 has a first side 45 a and a second side 45 b. A slot 46 extends from the mount end 42 toward the receiving end 43 within the second bore 44 . A second sheet 47 having an upper edge 47 a, a lower edge 47 b, an inner edge 47 c and an outer edge 47 d, is mounted proximate the upper edge 47 a to the second spin tube 41 substantially parallel to the second tube longitudinal axis and adjacent the second side 45 b of the channel 45 . Attached proximate the outer edge 47 d is an orthogonal tracking spacer 14 and proximate the lower edge 47 b is a rib 64 b. Disposed within the second bore 44 at the mount end 42 is a hollow drive gear 50 . The drive gear 50 has both a reduced portion which forms a spring receiver 51 and a tooth 52 for engaging the slot 46 . Disposed within the drive gear 50 is a hollow second bushing 53 . A second rod 54 having a second threaded end 55 and a spring end 56 is inserted through the second busing and the drive gear 50 and rotatably engages the first busing 32 . A spring 57 is disposed on the second rod 54 . One end of the spring 57 is fixedly mounted to the spring receiver 51 of the drive gear 50 , and the other end of the spring 57 is fixedly mounted to the spring end 56 of the second rod 54 . Disposed over the second threaded end 55 is a second washer 58 and a second cap 59 . The second threaded end 55 extends through and beyond the second cap 59 . Another mounting bracket 37 is placed onto the second threaded end 55 and secured to the second rod 54 and the second cap 59 by another nut 38 .
[0035] To obtain true telescoping ability, the first sheet is mounted utilizing the system of ridge and channel to allow the first tube to be inserted into the second tube without interference by the first sheet. To maintain orthogonal tracking, an adjustment may be made for the difference in the circumference of the roller assembly in the area where the sheets overlap, as compared to the non-overlapping areas, as the sheets are wound onto the roller. That is, when fully assembled, the inner edge 47 c of the second sheet 47 will overlap the inner edge 27 c of the first sheet 27 . This establishes a concentric relationship between the two sheets being wound. To maintain proper orthogonal tracking, and offset the extra layers accumulating at the overlapping portion of the sheets, the outer edge 47 d of the second sheet 47 carries an orthogonal tracking strip or spacer 14 . With each revolution of the roller, this orthogonal tracking spacer 14 increases the effective circumference of the cap end 42 of the second roller tube 41 to match that increase occurring where the two sheets overlap. Because the lower edge 47 b has an attached rib 64 b, the sheet material is kept flat and is able to bridge the unsupported area occurring in the center of the second roller tube 41 .
[0036] The first sheet 27 is wound upon the short collar 29 and the receiving end 43 of the second roller tube 41 for the first full revolution. At the beginning of the second revolution of the roller tubes 21 and 41 , the overlapping area of the second sheet 47 begins to be wound under the inner edge 27 c of the first sheet 27 . At this point in the winding process, the orthogonal tracking spacer 13 begins to adjust the circumference of the first roller tube 21 at the cap end 22 . This adjustment increases the circumference of the cap end 22 at the same rate occurring at the mating end 23 where sheets 27 and 47 overlap. This allows the sheets to maintain proper orthogonal tracking as they wind on and off the roller. Because the lower edge 27 b has an attached rib 64 a, the sheet material is kept flat and able to bridge the unsupported area occurring at the center of the first roller tube 21 , which results in proper orthogonal tracking.
[0037] With continued reference to FIG. 1 and additionally to FIGS. 2 and 3, the housing 60 has a housing longitudinal axis extending therethrough and comprises a hollow first cover tube 61 and a hollow second cover tube 62 . The first cover tube 61 has an outside diameter no larger than the inside diameter of the second cover tube 62 so that the first cover tube 61 is insertable into the second cover tube 62 . As shown in the drawings, the cover tubes 61 and 62 have a cylindrical shape; however, other shapes such as square, triangular, hexagonal and the like may be utilized with the present invention and are included within the scope of the present invention. Each of the cover tubes 61 and 62 has a slot 63 which extends substantially parallel to the housing longitudinal axis, preferably the entire length thereof. The first assembly 20 is inserted into the first cover tube 61 with the first sheet 26 extending through the slot 63 . The first cap 36 securely engages a respective end of the first cover tube 61 . Likewise, the second assembly 40 is inserted into the second cover tube 62 with the second sheet 47 extending through the slot 63 . The second cap 59 also securely engages a respective end of the second cover tube 62 . The first cover tube 61 and first assembly 20 are inserted into the second cover tube 62 and second assembly 40 with the slots 63 of each being aligned, thereby having a telescoping engagement.
[0038] Additionally, as the first spin tube 21 is inserted into the second spin tube 41 , the ridge 26 slidably engages the channel 45 and a rotational axis is formed between the first and second spin tubes 21 and 41 . Importantly, the second sheet inner edge 47 c overlaps the first sheet inner edge 27 c and the outer edge 47 d is supported by the orthogonal tracking spacer 14 . This defines a plane for the second sheet leading edge 47 a that is substantially parallel to the rotational axis and extends from the orthogonal tracking spacer 14 to the first sheet inner edge 27 c at any point in the winding process.
[0039] For the leading edge of the first sheet 27 , a plane substantially parallel to the rotational axis is established between the receiving end 43 of the second roller tube 41 and the short collar surface 31 for the first full revolution of the roller assembly. Because the first and second sheet inner edges 27 c and 47 c overlap, this plane changes at the beginning of the second revolution of the winding process. At the start of the second revolution, the circumference of the winding cylinder begins to grow twice as fast where the first and second sheets overlap as it does at the first roller tube cap end 22 . To maintain a plane substantially parallel to the rotational axis for the leading edge of the first sheet 27 , the orthogonal tracking spacer 13 begins to be wound under the first sheet outer edge 27 d at the start of the second revolution to compensate for the inner edge 47 c of the second sheet.
[0040] The width of the shade 10 can now be varied by extending or retracting the first cover tube 61 within and with respect to the second cover tube 62 .
[0041] As the first and second sheets 27 and 47 are extracted or pulled from the housing 60 , a standard spring motor is used to exert a biasing force to retract the first and second sheets 27 and 47 into the housing 60 .
[0042] Respectively mounted substantially perpendicular to the first and second sheets 27 and 47 proximate the first and second lower ends 27 b and 47 b are ribs 64 a and 64 b. As shown in FIGS. 1, 2 and 3 , the first and second sheets 27 and 47 contact one another at the first and second lower ends 27 b and 47 b. The ribs 64 a and 64 b are mounted to the sheets 27 and 47 so that each respective rib 64 a and 64 b projects outwardly and away from one another. Once the first and second sheets 27 and 47 have been withdrawn from the housing 60 so that the ribs 64 a and 64 b are a desired distance from the housing 60 , the retaining hook 70 is utilized to secure the sheets 27 and 47 to an object of a vehicle 1 , such as a vent 2 . The retaining hook 70 has a substantially U-shape body 71 and a substantially L-shaped hook 73 extending from the body 71 . Arms 72 project toward one another from the U-shaped body 71 , and the L-shaped hook has a catch 74 . The arms 72 removably engage the ribs 64 , and the catch 74 removably engages the vent 2 , or other object, of the vehicle 1 . Obviously, various types of securing devices such as buttons, locks, latches, hook and loop material, stops, brakes and the like may be utilized to prevent undesired retraction of the first and second sheets 27 and 47 , and are included within the scope of the present invention.
[0043] The first and second sheets 27 and 47 can be made of plastic, vinyl, cloth or any material capable of being rolled. Additionally each sheet 27 and 47 can comprise a light reflective material or have a light reflective coating or color on one or both sides.
[0044] With respect to the above description, it is to be realized that the optimum dimensional relationships for the parts of the invention, to include variations in size, materials, shape, form, function and manner of operation, assembly and use, are deemed readily apparent and obvious to one skilled in the art, and all equivalent relationships to those illustrated in the drawings and described in the specification are intended to be encompassed by the present invention. It should be understood that the foregoing relates only to the exemplary embodiments of the present invention, and that numerous changes may be made therein without departing from the spirit and scope of the invention as defined by the following claims. | An adjustable-width spring-operated roller shade that maintains proper orthogonal tracking at all available widths within the shade's range of width adjustment. The adjustable-width roller shade utilizes two overlapping window shades and a telescoping roller to provide a shade that is repeatedly width-adjustable within its original range of width adjustment. To keep the shade sufficiently perpendicular to the roller as the shade winds onto the roller, orthogonal tracking spacers, such as continuous, pliable strips constructed from the same material as the shades, are attached to non-overlapped portions of the shade material to compensate for the extra layers of material existing at the overlapped portion of the shades. Thus, the roller shade maintains proper orthogonal tracking of the shade at all available widths within the shade's range of width adjustment. | 4 |
BACKGROUND OF THE INVENTION
This invention relates to liquid-spraying arrangements for spraying a cleaning liquid on windows, such as motor vehicle windows, in which a spray has a liquid inflow chamber, through which cleaning liquid is received, and an interaction chamber having at least one outlet opening, through which the cleaning liquid flows out.
A liquid spraying arrangement of this type is disclosed in U.S. Pat. No. 3,973,558 which also describes an associated method for applying liquid to a window in a fan-like manner.
The disadvantage of such arrangements, however, is that very narrow channels have to be provided in order to make the water jet oscillate back and forth. Because of the desired fluid mechanics, it is not possible, with the desired volume flow, to increase the size of the channels since, otherwise, the water jet will not be made to oscillate as desired.
The disadvantage of having narrow channels is that in winter, at low temperatures, the cleaning liquid freezes very easily in the channels. If the cleaning liquid freezes in the channels, then the lack of liquid flow into the channels means that the oscillating movement of the water jet is no longer produced.
In addition, in order to prevent freezing, a nozzle of this type must be heated. Furthermore, with such narrow channels the oscillating water jet cannot be deflected in a different direction since, this would cause the desired flow effect to be lost.
A further disadvantage is that the emerging water jet is distributed over the window in a fan-like manner, i.e. the liquid is applied to a poorly defined region of the window and thus the majority of the cleaning liquid is not used for specific cleaning of the window.
U.S. Pat. No. 4,732,325 discloses a spray arrangement having a nozzle body which is mounted so that it can be tilted, the nozzle body being driven by a turbine which is caused to rotate by the water jet.
In this arrangement, the nozzle body is made to tilt by a comparatively complex and expensive mechanism. Moreover, in this case also the water jet can only be distributed in a fan-like manner.
It is not possible with this arrangement for the cleaning liquid to be sprayed alternately through two water jets which are spaced apart at an angle.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide a liquid spray arrangement for windows which overcomes the disadvantages of the prior art.
Another object of the invention is to provide a liquid spray arrangement by which a cleaning liquid can be sprayed onto a window alternately in different directions and in which the oscillating movement of the jet is produced, using a simple mechanism, by the flow of the cleaning liquid itself.
A further object of the invention is to provide a liquid spraying arrangement which does not lose its ability to function by freezing at low temperatures.
These and other objects of the invention are attained by providing a liquid spray arrangement having a spray nozzle with a liquid-receiving chamber and an interaction chamber, and an oscillator disposed in the interaction chamber so that it divides the interaction chamber into two spray channels and is caused to oscillate by the flow of the cleaning liquid in the interaction chamber.
If desired, the liquid receiving chamber and the interaction chamber may constitute a single chamber having a liquid-receiving region into which the cleaning liquid flows and an interaction region subdivided into two channels by the oscillator.
To provide the oscillating movement the oscillator is rotatably mounted on a pin and the compressive forces of the cleaning fluid acting on the lateral surfaces of the oscillator are changed automatically by oscillator motion. The forces exerted on the oscillator are the impulsive forces of the flowing liquid, and the forces on the oscillator which result from static pressure differences in the two spray channels.
In one embodiment of the invention the oscillator is subdivided by the pin into an outflow end and an inflow end so that the outflow end is longer than the inflow end.
This arrangement provides a simple way of producing the oscillating movement as a result of the flow of the cleaning liquid. The details of the flow mechanism are explained hereinafter with reference to an exemplary embodiment.
In operation, the entire flow of liquid during a spray operation passes through each of the two spray channels, which results in a sufficient channel width to assure that the cleaning liquid does not freeze even at very low temperatures.
If desired, a defined separation of the spray jets can be achieved, in the stop position of the oscillator, by selectively closing the spray channels at the inflow end and/or at outflow end.
In a further embodiment, the spray channels are connected to outflow channels which have a common angle adjustment device or separate angle-adjustment devices, such as adjustment balls containing the outflow channels. It is thus possible for the direction of each of the jets sprays to be set individually. The point of contact of each of the jet sprays with the window can thus be set so that it precisely covers the field of vision of the driver which is to be cleaned. Automatic spray-height adjustment depending on the vehicle speed or manual spray-height adjustment from the vehicle interior is also possible.
By using such spray jets that can be adjusted and sprayed alternately at different angles, it is possible to adapt the cleaning of the window specifically to the requirements of the driver and thus to reduce the proportion of the cleaning liquid used which does not contribute to the cleaning of the window. Less cleaning liquid is thus required to provide the same cleaning performance when cleaning the window, and the volume of the cleaning-liquid storage container can be correspondingly reduced without decreasing the intervals between filling of the storage container.
The nozzle has a simple construction and is inexpensive to produce and, because of the simplicity of the flow mechanism which triggers the oscillating movement, has a high functional reliability.
BRIEF DESCRIPTION OF THE DRAWINGS
Further objects and advantages of the invention will be apparent from a reading of the following description in conjunction with the accompanying drawings, in which:
FIG. 1 is a side view showing a representative embodiment of a liquid spray arrangement according to the invention;
FIG. 2 is a similar view showing another representative embodiment of a liquid spray arrangement in which the spray channel is closed at the outflow end;
FIG. 3 is a view showing a further embodiment with two outflow channels; and
FIG. 4 is a view showing another embodiment having two outflow channels, one of which is closed by the oscillator.
DESCRIPTION OF PREFERRED EMBODIMENTS
In the typical embodiment of the invention shown in FIG. 1 a spray nozzle 1 has a liquid-receiving inflow chamber 6 and an interaction chamber 16 and an oscillator 3 mounted in the interaction chamber 16 so that it can pivot around a pin 17, the pin being located off center in the interaction chamber 16. In this embodiment, the inflow chamber 6 is separated from the interaction chamber 16 by a narrowed section. The narrowed section, however, is not absolutely necessary. It is also possible for the interaction chamber to merge into the inflow chamber without any defined transition, so that the two chambers form a single chamber. The oscillator 3 subdivides the interaction chamber 16 into two spray channels 16a and 16b. Cleaning liquid flows from the inflow chamber 6 into the interaction chamber 16 and, from there, is sprayed onto a window (not illustrated) from an outlet opening 18.
Spray nozzles of this type are used, for example, for cleaning motor vehicle windows, the spray nozzle being arranged on or beneath the hood of the vehicle. As a result of an oscillating movement of the oscillator 3, cleaning liquid is sprayed onto the vehicle windshield alternately through the two spray channels 16a and 16b. The flow mechanism which causes the oscillating liquid movement will be explained in more detail hereinafter. The oscillating movement of the oscillator alternately narrows the inflow-end and/or outflow-end opening of the spray channels 16a and 16b so that the cleaning liquid is channeled alternately through the two spray channels. The direction of flow of the spray is determined by the geometry of the spray channels 16a and 16b.
The geometry of the spray channel 16a is determined by the oscillator and interaction chamber surfaces 10, 16c, 19 and 20 and the geometry of the spray channel 16b is determined by the oscillator and interaction chamber surfaces 8, 9, 16d and 22. In order to enhance the alternate outflow of the cleaning liquid, the oscillating movement may be such that the oscillator 3, in its stop positions, closes the inflow openings to the spray channels 16a and 16b by the surface 9 butting against the surface 8 or by the surface 19 butting against the surface 20. When the inflow to one spray channel (e.g. the spray channel 16a in FIG. 1) is closed, the outflow of the other spray channel (the spray channel 16b) in FIG. 1 is also closed.
In this case, spraying takes place each time through one of the spray channels 16a and 16b while the other spray channel is being filled.
The oscillating movement is produced as follows:
The oscillator 3 is initially located in any position. The cleaning liquid flows into the interaction chamber from the inflow chamber 6 and, by virtue of the impulsive force on the surface 9 or 19, moves the oscillator into one of the two stop positions, with the result that the surfaces 19 and 20 or 9 and 8 butt against one another. In the condition shown in FIG. 1, the surface 19 butts against the surface 20. The flow of the cleaning liquid causes different forces to act on the inflow end 3a and outflow end 3b of the oscillator. These forces may be produced in a simple manner by speeding up or slowing down the flow of cleaning liquid. Thus, the spray channel 16a or 16b may be opened at the outflow end 3b of the oscillator 3 by decreasing the flow speed and increasing the static pressure in the flow. Even if the ends 3a and 3b of the oscillator are of equal length, this has the effect of causing a higher pressure to be applied at the outflow end, in the channel through which flow takes place, than at the inflow end, and the oscillator is thus made to pivot in the counterclockwise direction from the position shown in FIG. 1 until its surface 9 butts against the surface 8. However, with a constant spray-channel width in the stop position, the pivot movement may also be achieved by the outflow end of the oscillator being longer than the inflow end. On account of the constant channel width, and with constant channel height, the static pressure is likewise constant along one stream filament. Since the surface of the outflow end is larger than the surface of the inflow end, the force applied to the oscillator at the outflow end is greater than that at the inflow end. The pivot movement is then triggered because of the imbalance of forces.
As the pivot movement commences, some of the cleaning liquid also begins to flow into the spray channel 16a. The proportion of the cleaning liquid which flows into the spray channel 16a increases as the pivot angle of the oscillator 3 increases, until the surface 9 butts against the surface 8, causing the inflow to the spray channel 16b to be closed and the cleaning liquid being sprayed onto the window exclusively from the spray channel 16a. The pivot movement may also be triggered by impulsive forces exerted on the oscillator by the cleaning liquid. The impulsive forces acting on the oscillator may be specifically influenced by the shape of the oscillator. The oscillator may thus have, for example, thickened sections at certain points, these sections providing resistance to the flow and producing impulsive forces which act on the oscillator.
In the embodiment shown in FIG. 2, a surface 22 of the oscillator butts against a surface 21 of the outlet opening and thus closes the spray channel 16b at the outflow end. The cleaning liquid then exerts an impulsive force on the outflow end 3b of the oscillator, and this causes the oscillator to pivot toward the opposite spray channel surface.
It is conceivable, in theory, for the oscillator to remain in the central position in the nozzle and for the cleaning liquid to be sprayed onto the window through two spray channels simultaneously. In such cases, however, vibrations which occur in a vehicle will always deflect the oscillator out of the central position and thus trigger the oscillating movement.
In the embodiment shown in FIG. 3, a specific separation of the spray jets leading from the spray channels 16a and 16b is achieved by providing separate outflow channels 4 and 5 for the spray channels 16b and 16a, respectively, as shown in FIG. 3. At least part of the outflow channels may pass through corresponding direction control balls 11 and 12. This makes it easy to adjust the angle of contact of the spray on the window.
In the embodiment shown in FIG. 4, the surfaces 10 and 22 are shaped so that, in each stop position of the oscillator, the spray channel 16a or 16b, formed by the surfaces 10, 19 and 16c or 22, 9 and 16d, through which the cleaning liquid is being sprayed merges continuously into a corresponding outflow channel 4 or 5. The alternate outflow is further enhanced by providing an end surface 13 on the oscillator which closes an outflow channel 4 or 5 when the oscillator is in a stop position.
Although the invention has been described herein with reference to specific embodiments, many modifications and variations therein will readily occur to those skilled in the art. Accordingly, all such variations and modifications are included within the intended scope of the invention. | A liquid spray arrangement for a window has a spray nozzle which includes an inflow chamber, an interaction chamber, and an oscillator in the interaction chamber. The oscillator divides the interaction chamber into two spray channels and is caused to oscillate by the flow of a cleaning liquid, as a result of which a spray jet is sprayed onto the window alternately at two different angles. This makes it possible to increase the proportion of cleaning liquid which contributes to the cleaning of the window, and thus to reduce the volume of cleaning liquid in the storage container. | 1 |
TECHNICAL FIELD
[0001] The present invention is related to relates generally to computer security and malware protection and, more particularly, to a method for atomic detection and repair of kernel memory.
BACKGROUND
[0002] Computer malware operating in a multi-core or multi-processor environment may be difficult to detect and remove. In addition, such malware may make malicious modifications to kernel memory of a computer system. Such malware may thus be running at a very low level of a system.
[0003] Atomic operation of instructions on a processor or core may mean the ability of those instructions to run without being interrupted by the system. The ability of a process, thread, or other set of instructions to run atomically on a system may be handled by establishing a hierarchy of such instructions. The ability of one instruction to be executed over another may be resolved by determining which instruction was first received, or which one is the shorter or lower-level instruction.
[0004] Malware may include, but is not limited to, spyware, rootkits, password stealers, spam, sources of phishing attacks, sources of denial-of-service-attacks, viruses, loggers, Trojans, adware, or any other digital content that produces malicious activity.
SUMMARY
[0005] A method for detecting memory modifications includes allocating a contiguous block of a memory of an electronic device, and loading instructions for detecting memory modifications into the contiguous block of memory. The electronic device includes a plurality of processing entities. The method also includes disabling all but one of a plurality of processing entities of the electronic device, scanning the memory of the electronic device for modifications performed by malware, and, if a memory modification is detected, repairing the memory modification. The method also includes enabling the processing entities that were disabled. The remaining processing entity executes the instructions for detecting memory modifications.
[0006] In a further embodiment, an article of manufacture includes a computer readable medium and computer-executable instructions. The computer-executable instructions are carried on the computer readable medium. The instructions are readable by a processor. The instructions, when read and executed, cause the processor to allocate a contiguous block of a memory of an electronic device, load instructions for detecting memory modifications into the contiguous block of memory, disable all but one processing entity of the electronic device, scan the memory of an electronic device for modifications performed by malware, repair a detected memory modification, and enable the processing entities that were disabled. The electronic device includes a plurality of processing entities. The remaining processing entity executes the instructions for detecting memory modifications.
BRIEF DESCRIPTION
[0007] For a more complete understanding of the present invention, and the advantages thereof, reference is now made to the following written description taken in conjunction with the accompanying drawings, in which:
[0008] FIG. 1 is an example embodiment of a system for atomic detection and repair of kernel memory based malware in a multi-core processor environment;
[0009] FIG. 2 is a further illustration of the components of an electronic device in a system for atomic detection and repair of kernel memory; and
[0010] FIG. 3 is an example embodiment of a method for atomic detection and repair of kernel memory-based malware in a multi-core processor environment.
DETAILED DESCRIPTION OF THE INVENTION
[0011] FIG. 1 is an example embodiment of a system 100 for atomic detection and repair of kernel memory based malware in a multi-core processor environment. System 100 may comprise an anti-malware application 102 configured to scan electronic device 104 for malware. Anti-malware application 102 may be configured to operate on electronic device 104 . Anti-malware application 102 may be communicatively coupled to electronic device 104 over a network. Anti-malware application 102 may be configured to run on a network such as a cloud computing network. Anti-malware application 102 may be communicatively coupled to an anti-malware server 114 over a network such as network 112 . Anti-malware application 102 may be configured to determine the presence of kernel-memory-related malware on electronic device 104 . Electronic device 104 may include multiple processing entities. In one embodiment, such processing entities may include processors or processing cores. Electronic device 104 may include a multicore processor environment.
[0012] Electronic device 104 may include one or more processors 106 coupled to a memory 108 . Processors 106 may each include one or more cores 110 . One or more processors 106 may each be coupled to other processors 106 . For example, processor 106 A may include core 110 A and core 110 B. Processor 106 A may be coupled to processor 106 B, 106 C and 106 D. In one embodiment, each processor 106 may include an even number of cores. In various embodiments, processor 106 may include two cores, four cores or eight cores. Each processor 106 may include an interrupt controller. In one embodiment, processors 106 may each include an advanced programmable interrupt controller (“APIC”). APIC 116 may be configured to combine interrupts into one or more communication mechanisms per processor 106 . APIC 116 may be configured to assign priority to one or more interrupts received by processor 106 .
[0013] Anti-malware application 102 may be configured to receive detection information from anti-malware server 112 . Such detection information, may include, but is not limited to, antivirus signatures, behavioral rules, reputation analysis or any other suitable mechanism for detecting the presence of malware on electronic devices such as electronic device 104 . Anti-malware application 102 may be configured to apply detection information for the detection of malware on electronic device 104 at any suitable time. For example, anti-malware application 102 may be configured to scan electronic device 104 upon demand by a user or administrator of electronic device 104 for malware, or at a regularly scheduled or periodic time. In yet another embodiment, anti-malware application 102 may be configured to scan electronic device 104 for malware upon the detection of suspicious behavior or evidence indicating that electronic device 104 may be infected with malware.
[0014] Network 112 , or any other networks used in system 100 , may include any suitable networks for communication between electronic device 104 , anti-malware application 102 , and anti-malware server 114 . Such networks may include but are not limited to: the Internet, an intranet, wide-area-networks, local-area-networks, back-haul-networks, peer-to-peer-networks, or any combination thereof.
[0015] Each of processors 106 may be implemented, for example, by a microprocessor, microcontroller, digital signal processor (DSP), application specific integrated circuit (ASIC), or any other digital or analog circuitry configured to interpret and/or execute program instructions and/or process data. In some embodiments, each of processors 106 may interpret and/or execute program instructions and/or process data stored in memory 108 . Memory 108 may be configured in part or whole as application memory, system memory, or both. Memory 108 may include any system, device, or apparatus configured to hold and/or house one or more memory modules. Each memory module may include any system, device or apparatus configured to retain program instructions and/or data for a period of time (e.g., computer-readable media).
[0016] FIG. 2 is a further illustration of the components of electronic device 104 in a system for atomic detection and repair of kernel memory. Electronic device 104 may include, for example, one or more processors 106 A and 106 B, operating system 206 , kernel memory 208 , and various memory allocations such as processor memory allocation 204 and core memory allocation 206 . Each processor 106 may contain one or more cores 110 . Each core 110 may be assigned a memory allocation, such as core memory allocation 204 . Each processor 106 may be assigned a processor memory allocation 206 . Each processor 106 may be coupled to other processors. Each core 110 may be configured to access operating system 206 or various sections of memory such as kernel memory 208 . Each core 110 on a processor 106 may be configured to have one or more threads running in such a core. For example, core 110 B of processor 106 A may be executing Thread_ 1 206 . In another example, processor 106 B may contain core 110 c which may be executing Thread_ 2 208 .
[0017] Operating system 206 may be configured to provide system services to electronic device 104 . Operating system 206 may be implemented in any suitable software for providing operating system services to an electronic device. Operating system 206 may be coupled to kernel memory 208 .
[0018] Anti-malware application 102 may be configured to scan electronic device 104 for the presence of malware by the execution of anti-malware process 202 . Anti-malware process 202 may execute in any of the cores 110 of any of the processors 106 on electronic device 104 . Anti-malware process 202 may be configured to execute on the primary core of electronic device 104 . Anti-malware process 202 may execute as a standalone process separate from anti-malware application 102 . In one embodiment, anti-malware application 102 may be configured to launch the execution of anti-malware process 202 . In such an embodiment, anti-malware application 102 may be configured to cease execution while anti-malware process 202 continues execution and scanning of malware on electronic device 104 . Anti-malware process may be configured to scan kernel memory 208 for evidence of kernel mode memory malware. Anti-malware process 202 may be configured to use various parts of operating system 206 in order to scan kernel memory 208 for malware.
[0019] Anti-malware process 202 may be configured to scan any suitable portion of kernel memory 208 which may be infected with malware, or affected by such an infection. For example, anti-malware process 202 may be configured to scan a file system driver stack 210 , network driver stack 212 , display driver stack 214 , device driver code 216 , kernel code 218 , keyboard driver stack 220 , active process list 222 , open network sockets 224 , or system service dispatch table 226 for indications of malware. Malware, or indicators of malware, may be present in various portions of kernel memory 208 . Anti-malware process 202 may be configured to detect and undo the effects of malware in kernel memory 208 of malware operating in cores such as 110 A, 110 B and 110 c.
[0020] Other anti-malware software may be limited to detecting the operation of malware processes only in the same core in which the other anti-malware software is currently operating. However, in the example of FIG. 2 , while anti-malware process 202 is operating in core 110 A, anti-malware process 202 may be configured to detect the effects of malware of threads operating in other cores, such as Thread_ 1 206 in core 110 B, or Thread_ 2 208 in core 110 c . If malware, operating as part of Thread_ 1 206 or Thread_ 2 208 , detect the presence or scanning and repairing operation of anti-malware process 202 , such malware may tamper with, obstruct, remove, or otherwise counteract anti-malware process 202 or the changes enacted by anti-malware process 202 . One way that such malware may hamper anti-malware process 202 is by configuring Thread_ 1 206 or Thread_ 2 208 to have a higher priority or an equal priority to anti-malware process 202 . For example, Thread_ 1 206 and Thread_ 2 208 may be operating in a ring zero of the operation of electronic device 104 . As such, the operation of Thread_ 1 206 and Thread_ 2 208 may be described as “atomic.”
[0021] Anti-malware process 202 may be configured to subvert the execution of threads on cores other than the core on which anti-malware process 202 is running in order that anti-malware process 202 may execute atomically, or without risk of interruption by threads operating in other cores or processors. In one embodiment, anti-malware process 202 may be configured to stop the execution of threads on other cores such as Thread_ 1 206 and Thread_ 2 208 , whether such cores are located on the same processor 106 as anti-malware process 202 or not. In a further embodiment, anti-malware process 202 may be configured to cease the operation of the cores other than core 110 A, the core upon which anti-malware process 202 's is operating.
[0022] Anti-malware process 202 may be configured to allocate a contiguous block of memory in kernel memory 208 . In one embodiment, such a contiguous block of memory may be implemented in kernel non-pageable memory pool 230 . Kernel non-pageable memory pool 230 may include a contiguous block 232 of memory.
[0023] Anti-malware process 202 may be configured to operate inside of kernel non-pageable memory pool 230 . In one embodiment, anti-malware process 202 may be configured to operate inside a contiguous block 232 . Anti-malware application 102 may be configured to set up the execution of anti-malware process 202 inside of kernel non-pageable memory pool 230 . Contiguous block 232 may thus include malware detection and repair logic malware detection and repair logic for scanning kernel memory 208 for malware and for repairing the effects of malware found in kernel memory 208 . Anti-malware process 202 may be configured to turn off all processors in electronic device 104 , except for the processor upon which anti-malware process 202 is running. For example, anti-malware process 202 may be configured to turn off execution of processor 106 B, leaving processor 106 A executing. Anti-malware process 202 may be configured to run on the base system processor. Anti-malware process 202 may be configured to disable interrupts of operating system 206 . Such interrupts may include application interrupts 238 , kernel interrupts 240 and scheduler timer interrupt 242 . Application interrupts 238 may include interrupts that may originate from applications of electronic device 104 . Kernel interrupts 240 may include interrupts that originate from portions of electronic device 104 having kernel level access. Scheduler timer interrupt 242 may comprise an interrupt for scheduling execution of threads in a given processor or core. Interrupts such as application interrupts 238 , kernel interrupts 240 and scheduler timer interrupt 242 may be implemented fully or in part by APIC 116 . Configuring anti-malware process 202 to shut down scheduler timer interrupt 242 may cause all running processes on electronic device 104 to cease operation except anti-malware process 202 .
[0024] Anti-malware process 202 may be configured, when scanning electronic device 104 for memory modifications, to be the only process or thread running on any core 110 or processor 106 of electronic device 104 . Anti-malware process 202 may be configured to then scan kernel memory 208 for modifications made by malware and subsequently repair kernel memory 208 of any such modifications or other effects of malware. Anti-malware process 202 may be configured to scan kernel memory 208 for any suitable memory modification performed by malware. Anti-malware process 202 may be configured to scan any suitable portion of kernel memory 208 for malicious modifications made by malware.
[0025] For example, file system driver stack 210 may be modified to include a malware hook among the different drivers in the stack. Keyboard driver stack 220 may have a key logger hook embedded among one or more other drivers. Active process list 222 may have been modified to eliminate the presence of, for example, Thread_ 2 , in active process list 222 , or may have been modified in such a way to disguise the presence of Thread_ 2 in active process list 222 . Open network sockets 224 may have been modified to eliminate information showing that Port_ 2 is or has been accessed. Code sections of the kernel in kernel code 218 may have been modified by malware, as may have the code of a device driver in device driver code 216 . System service dispatch table 226 may have been modified so as to change a service executable module or other digital entity which is pointed to by entries in system service dispatch table 226 . For example, Service 2 in entry in system service dispatch table 226 may have originally pointed to a particular service 228 posted by operating system 206 . Instead, malware may have modified system service dispatch table 226 entry for Service 2 to point instead to a shared library 227 . Such a redirection may comprise a malware infection. Modifications to kernel data structures such as active process list 222 , open network sockets list 224 , and other data structures may have been made to hide evidence of malware. Changes to various stacks, such as driver stack 210 , keyboard driver stack 220 , network driver stack 212 and display driver stack 214 may have been made by inserting malicious code in a layer of the driver stack to disguise the presence of malware. To detect memory modifications in such elements, anti-malware process 202 may be configured to examine different portions of kernel memory 208 and compare them against, for example, known safe values or known signatures corresponding to malware.
[0026] Because scheduler timer interrupts 242 may have been disabled by anti-malware process 202 , anti-malware process 202 might not be configured to access various features, capabilities or services of operating system 206 while scanning electronic device 104 for malicious memory modifications. For example, anti-malware process 202 might not be able to access various portions of system memory unless the memory is pinned and locked. In another example, anti-malware process 202 may not be configured to access an operating system function unless the function operates independently of creating or referencing a kernel dispatchable object.
[0027] Anti-malware process 202 may be configured to repeatedly enable and disable some or all of operating system 206 , as needed to access various portions of operating system 206 while scanning electronic device 104 for malicious memory modifications. Anti-malware process 202 may be configured to temporarily enable one or more services available of operating system 206 . Anti-malware process 202 may be configured to verify the infection status of a given process or service, or of memory associated with such a given process or service, as not infected by malware before using such a process or service.
[0028] In one embodiment, the teachings of the present disclosure may be applied to configure anti-malware process 202 to detect the infection of malware in user mode memory. An example of such user mode memory may be core memory allocations 204 . Possibly malicious threads may be running in such a core memory allocation 204 and may work to subvert the operation of an anti-malware process such as anti-malware process 202 , as anti-malware process 202 attempts to detect and repair memory modifications or process infections in user mode memory. Anti-malware process 202 may be configured to lock a process of a core into a particular segment of core memory allocation 204 , and subsequently scanning and repairing the processed memory into which the thread or process has been locked.
[0029] In operation, one or more processors 106 may be executing one or more threads in one or more cores 110 on electronic device 104 . One or more threads operating on electronic device 104 may be a portion of a malicious program such as malware. In one embodiment, a single processor 106 on electronic device 104 may be executing two or more cores 110 . In another embodiment, two or more processors 106 may be executing on electronic device 104 . In such an embodiment, each processor 106 may have a single core or more than one core 110 . Each core of electronic device 104 may be executing one or more threads. Anti-malware application 102 may receive detection information from anti-malware server 114 over network 112 . Anti-malware application 102 may receive detection information such as logic to determine whether modifications have been made to memory 108 of electronic device 104 that are malicious and possibly created by malware.
[0030] Anti-malware application 102 may be executing on a cloud computing scheme. In another embodiment, anti-malware application 102 may be executing on electronic device 104 . Anti-malware application 102 or anti-malware process 202 may reserve a contiguous block 232 of memory inside of kernel memory 208 . In one embodiment, such a reservation may be made in kernel non-pageable memory pool 230 . Anti-malware process 202 may begin executing in contiguous block 232 .
[0031] Anti-malware process 202 may contain malware detection and repair logic sufficient to scan kernel memory 208 for memory modifications made by malware, and repairing such modifications. Anti-malware application 104 may initiate operation of anti-malware process 202 .
[0032] Anti-malware process 202 may turn off all processors 106 in electronic device 104 except for the processor 106 A upon which anti-malware process 202 is executing. Anti-malware process 202 may switch off the execution of all cores 110 which may be executing on electronic device 104 except for the core 110 A upon which anti-malware process 202 may be executing. Anti-malware process 202 may disable all interrupts of an operating system 206 of electronic device 104 . Such interrupts may include application interrupt 238 including user mode interrupts, kernel interrupts 240 including kernel mode interrupts, and any scheduler timer interrupts 242 .
[0033] Anti-malware process 202 may use any suitable method for disabling the operation of processors 106 , cores 110 and interrupts 238 , 240 , 242 . In one embodiment, anti-malware process 202 may directly program electronic device 104 and processors 106 to disable the operation of processors 106 and core 110 . In such an embodiment, anti-malware process 202 may access a programmable interrupt controller of a given processor 106 B. Such a programmable interrupt controller may include advanced programmable interrupt controller (APIC) 116 . The commands or methods used to program advanced programmable interrupt controller 116 may depend upon the specific processor 106 chosen to implement system 100 . Anti-malware process 202 may directly program processor 106 B to disable interrupts and processing by programming APIC 116 using inert processor interrupts.
[0034] In another embodiment, anti-malware process 202 may use a service provided by operating system 206 to disable operation of processor 106 B or of operating system 206 . In such an embodiment, the commands used to disable operation of processor 106 B and operating system 206 may be specific to the operating system 206 running on electronic device 104 . In such an embodiment, a kernel debugging facility of operating system 206 may be used. Such a built in kernel debugger may have services available to freeze and resume execution of operating system 206 . For example, in the kernel mode of the Windows operating system, two instructions may be suitable for use by anti-malware process 202 to disable the operation of processor 106 and operating system 206 . Two such functions are KeFreezeExecution and KeThawExecution. Anti-malware application 102 or anti-malware process 202 may be configured to access such functions by computing their address and calling their functions directly in memory 108 . In such an example, KeFreezeExecution, or an equivalent function, may perform the following steps: (a) disabling interrupts of operating system 206 ; (b) calling an interprocessor interrupt service to notify the service that execution will be frozen; (c) calling into the hardware abstraction layer (HAL) exported function called KeStallExecutionProcessor, to stall processor execution of all processors except the current processor; and (d) notify other processors, such as 106 B, that execution is to be frozen, by sending interprocessor interrupts via the calling the HAL function HalRequestIpi. Anti-malware process 202 may call the freeze function to freeze execution of processors 106 and call the thaw function to unfreeze execution of processors 106 .
[0035] After putting processors 106 or cores 208 in suspended operation, anti-malware process 202 may examine kernel memory 208 for possible malicious memory modifications. For example, anti-malware process 202 may examine file system driver stack 210 to determine whether or not malware has been inserted inside of the driver stack, in the form of a hook. Anti-malware process 202 may similarly examine network driver stack 212 or display driver stack 214 . Anti-malware process 202 may examine keyboard driver stack 220 to determine, for example, whether a key logger hook has been inserted inside of the stack. Such hooks may be used to mine information from memory or to disguise the presence of other malicious pieces of code. Anti-malware process 202 may examine active process list 222 to determine whether any modifications have been made to hide the execution of a malware process. For example, if Thread_ 2 208 operating in core 110 c on processor 106 B comprises malware, active process list 222 may have been modified to hide the presence of Thread_ 2 208 as an active thread. Anti-malware process 202 may examine open network sockets 224 to determine whether modifications have been made to disguise the network access of an application. Such modifications may be used to hide the network access of malware. For example, if Port_ 2 were being used by Thread_ 2 208 , a malicious process, open network source sockets 224 may be modified to hide the access of Port_ 2 . Anti-malware process 202 may examine system service dispatch table 226 to determine whether service dispatches have been modified to redirect execution to other services, modules, strips or libraries. For example, Service_ 3 may be redirected by malware to point to shared library 227 instead of Service_ 3 of operating system 206 . Such a redirection may be an attempt to run malicious code instead of a trusted service.
[0036] Once anti-malware process 202 has determined a portion of kernel memory 208 has been infected with a memory modification by malware, anti-malware process 202 may take steps to correct the memory modification of kernel memory 208 . To correct memory modifications, anti-malware process 202 may re-enable portions of operating system 206 , access parts of electronic device 104 needed to repair memory modifications by malware, and then again disable operating system 206 and processors 106 . Anti-malware process 202 may clean or verify system components before activating them for the purposes of cleaning other portions of electronic device 104 . For example, if anti-malware process 202 determines that system service dispatch table 226 has been modified by malware, anti-malware process 202 may re-enable portions of operating system 206 to access the original code bytes of the modified image on disk of the system service dispatch table 226 . Anti-malware process 202 may then copy the original code bytes of the modified image and copy them into non-pageable kernel memory 230 . Anti-malware process 202 may then again disable operating system 206 and any processors 106 that have been activated. Anti-malware process 202 may then examine the correct values for the code bytes for the image of system service dispatch table 226 , and repair system service dispatch table 226 in safety without fear of modifications by other malicious malware running in other threads such as Thread_ 2 208 . For malware memory modifications in portions of kernel memory 208 , such as code sections in device driver code 216 or kernel code 218 , that cannot be reloaded, anti-malware process 202 may fill the pages of the memory infection with NOP instructions or place a return or a jump to avoid execution of the malicious code. Anti-malware process 202 may make similar activations and deactivations of portions of operating system 206 or processors 106 in order to systematically scan kernel memory 208 for infections, make repairs, and reactivate portions of operating system 206 and processors 106 , as various portions of operating system 206 , kernel memory 208 and processors 106 are deemed safe and clean by anti-malware process 202 .
[0037] In one embodiment, anti-malware process 202 may be applied to memory that is non-pageable. In such an embodiment, anti-malware process 202 , before freezing execution, may lock memory pages of memory 108 needed to scan.
[0038] In one embodiment, anti-malware process 202 may scan application memory, such as memory allocation 206 or core memory allocation 204 . In such an embodiment, anti-malware process 202 may force an attachment into the target process address space. In the Windows operating system environment, one method for accomplishing such a task is to call the function KeStackAttachProcess. The target applications whose application memory is to be scanned may be locked. Anti-malware process 202 may alternate between switching to different process contexts, freezing and resuming the execution in between scanning and repairing process memories associated with cores 110 or processor 106 .
[0039] FIG. 3 is an example embodiment of a method 300 for atomic detection and repair of kernel memory-based malware in a multi-core processor environment. In Step 305 , a contiguous block of non-pageable memory may be allocated. The contiguous block of kernel memory may be configured for an anti-malware process to operate and scan the kernel memory of an electronic device for memory modifications conducted by malware. In Step 310 , detection and repair instructions may be loaded into the contiguous block. Such detection and repair instructions may make up an anti-malware application or a portion of an anti-malware application.
[0040] In Step 315 , all processors and cores, except for the core and processor upon which the detection and repair instructions are loaded, may be shut down. The anti-malware application may change its thread affinity to make it run on the base system processor or the primary core. In one embodiment, Step 315 may be implemented by directly programming the system or a local processor programmable interrupt controller. In another embodiment, Step 315 may be implemented by an operating system service provided for the shutting down of processors or cores. Such a service may consist of a kernel debugging facility. In a system using a Windows operating system, for example, the kernel mode of the operating system may provide an undocumented instruction called KeFreezeExecution that may freeze execution of a processor or of the operating system. Likewise, another undocumented function, KeThawExecution may be provided to reverse the effects of KeFreezeExecution.
[0041] In Step 320 , system interrupts of the operating system of the electronic device may be disabled. In one embodiment, the system and any processors may be directly programmed using inert processor interrupts. In Step 325 , a scheduler timer interrupt may be disabled. The scheduler timer interrupt disablement may suspend new operations being scheduled by an operating system of the electronic device. In Step 330 , kernel memory may be scanned for malicious modifications conducted by malware. Any suitable part of kernel memory of the electronic device may be scanned for such memory modifications. Such modifications may be in a driver, driver stack, kernel data structures, code sections, or a system service dispatch table. Any suitable method for scanning for memory modifications may be used.
[0042] In Step 335 , if modifications are not found, then in Step 350 , the processors, cores and interrupts of the electronic device may be reactivated. If modifications are found in Step 335 , then processors, cores and interrupts necessary to allow sufficient system access for a repair of the memory modification may be optionally enabled in Step 340 . Whether such resources will be enabled may depend upon the specific type of memory modification and necessary course of repair required, as well as whether such resources may be trusted to be free of malware. In Step 345 , the memory modifications may be reversed, repaired, or otherwise neutralized or corrected. After modifications have been repaired, any processors, cores or interrupts that have been re-enabled may then be disabled. Optionally, Step 330 may be repeated as other portions of kernel memory are scanned for malicious memory modifications until the system has been determined to be cleaned of memory modifications.
[0043] Method 300 may be implemented using the system of FIGS. 1-2 , or any other system operable to implement method 300 . As such, the preferred initialization point for method 300 and the order of the steps comprising method 300 may depend on the implementation chosen. In some embodiments, some steps may be optionally omitted, repeated, or combined. In some embodiments, portions of method 300 may be combined. In certain embodiments, method 300 may be implemented partially or fully in software embodied in computer-readable media.
[0044] For the purposes of this disclosure, computer-readable media may include any instrumentality or aggregation of instrumentalities that may retain data and/or instructions for a period of time. Computer-readable media may include, without limitation, storage media such as a direct access storage device (e.g., a hard disk drive or floppy disk), a sequential access storage device (e.g., a tape disk drive), compact disk, CD-ROM, DVD, random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), and/or flash memory; as well as communications media such wires, optical fibers, and other tangible, non-transitory media; and/or any combination of the foregoing.
[0045] Although the present invention and its advantages have been described in detail, it should be understood that various changes, substitutions and alternations can be made herein without departing from the spirit and scope of the invention as defined by the following claims. | A method for detecting memory modifications includes allocating a contiguous block of a memory of an electronic device, and loading instructions for detecting memory modifications into the contiguous block of memory. The electronic device includes a plurality of processing entities. The method also includes disabling all but one of a plurality of processing entities of the electronic device, scanning the memory of the electronic device for modifications performed by malware, and, if a memory modification is detected, repairing the memory modification. The method also includes enabling the processing entities that were disabled. The remaining processing entity executes the instructions for detecting memory modifications. | 6 |
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0001] Not Applicable
THE NAME OF THE PARTIES TO A JOINT RESEARCH AGREEMENT
[0002] Not applicable.
INCORPORATION-BY-REFERENCE OF MATERIAL SUBMITTED ON A COMPACT DISC
[0003] Not Applicable
BACKGROUND OF THE INVENTION
[0004] In the U.S. patent application Ser. No. 12/590,658, an injection device 1 was disclosed that would reduce or prevent the pain associated with injection, and surgical procedures such as puncture, incision, or otherwise violation of the skin barrier, using electrical and physical stimulation, simultaneously or consecutively, of the area of the skin or mucosa in the vicinity of the injection, puncture, incision, or otherwise violation of the skin or mucosa barrier. In this application, various components of said injection device 1 are disclosed. Furthermore, a container 18 of injectable solution is also disclosed with improved characteristics.
BRIEF SUMMARY OF THE INVENTION
[0005] A container of injectable solution and a syringe is disclosed that includes sensors and various components to help proper administration of injection by an automated injecting device.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0006] FIG. 1 shows a container of injectable solution including a memory device, electrodes, a needle, and an electrical switch connected to a processor. It also shows various components of a preferred embodiment of a container of injectable solution.
[0007] FIGS. 2 & 3 show how a flexible area inflates when a plunger pushes the contents towards the needle and the adjacent flexible area.
[0008] FIG. 4 depicts a container of injectable solution including a means to allow the plunger to move only in one direction.
[0009] FIG. 5 illustrates a container of injectable solution including a plurality of electrodes, a barometer, and a memory device.
[0010] FIGS. 6 a & 6 b show how a flexible area breaks an electrically conductive means when it inflates or deflates.
[0011] FIG. 7 illustrates a needle including a tip, a canal, a segment with a larger canal, and a semi-pervious object placed in the larger canal.
[0012] FIG. 8 shows a container including a plurality of wires that are attached to a plurality of connectors.
DETAILED DESCRIPTION OF THE INVENTION
[0013] Reference is made to U.S. patent application Ser. No. 12/590,658, filed on Nov. 12, 2009 to establish the priority date for various aspects of the following invention.
[0014] In a specific example of the invention, a container of injectable solution 18 is disclosed, including a plurality of ports 27 made for example of rubber. Said plurality of ports 27 are penetrable by a needle of a syringe (not shown) to extract its contents 25 , FIG. 5 . Said container 18 has a plurality of flexible areas 23 that can be forced to move outwards out of or inwards into said container 18 depending on increased or decreased pressure, respectively, inside said container 18 . The first advantage of this design is to relatively equilibrate the pressures inside and outside of said container 18 during extracting the contents 25 . Since extracting the contents 25 creates a relative vacuum inside said container 18 , it would increasingly become difficult to extract the contents 25 as the contents 25 are emptied unless the vacuum is filled. In order to do so, said plurality of flexible areas 23 expand inward due to relatively higher outside pressure, filling the vacuum, and facilitating further extraction of said contents 25 from said container 18 . In a preferred example of the invention, before extraction of the contents 25 , a fluid such as a gas is injected into said container 18 through said plurality of ports 27 , inflating said plurality of expandable areas 23 . This method facilitates extraction of more of said contents 25 before encountering a strong enough vacuum to hamper proper extraction of said contents 25 .
[0015] In a specific example of the invention, said injecting device 1 includes means to automatically apply electric and physical stimulation to the area of injection, actuate the penetration of a plurality of needles 8 into the recipient's skin, and injection of the contents 25 of said plurality of containers 18 , through said plurality of needles 8 , using various motors to actuate different steps, a processor 14 to control, guide, and time these steps, and various sensors to ascertain successful completion of each step, FIG. 1 .
[0016] In a specific example of the invention, this design is used to assure that said container 18 has no cracks and that the process of extraction of said contents 25 is carried out properly. When injecting gas into said container 18 or extracting said contents 25 therefrom, the pressure inside said container 18 changes relative to the outside pressure. This will lead to expansion of said plurality of flexible areas 23 outwards from or inwards into said container 18 . This will indicate proper content 25 extraction from said container 18 , because if, for any reason, said contents 25 were not extracted, said plurality of flexible areas 23 would not expand into said container 18 . This advantage becomes more apparent when the extraction is performed automatically by said injecting device 1 . Since visual verification of proper content extraction from said container 18 may not be feasible, the expansion of said plurality of flexible areas 23 with change of pressure inside said container 18 proves to be a reliable indicator of successful content 25 extraction from said container 18 . A sensor (not shown) inside said injecting device 1 can be used to detect inward or outward expansion of said plurality of flexible areas 23 , relay this message to said processor 14 which will in turn allow the extraction process to proceed, FIGS. 2 and 3 .
[0017] In a specific example of the invention, said plurality of flexible areas 23 lose their expansion capacity after a period of time. That period of time can be made to coincide approximately with the expiration date of said contents 25 of said container 18 . Therefore, at the expiration date of said contents 25 , said plurality of flexible areas 23 do not expand as a response to a change in pressure inside said container 18 . The sensor inside said injecting device 1 does not detect any inward or outward expansion of said plurality of flexible areas 23 , no message is relayed to said processor 14 which will in turn not allow the extraction process to proceed. This can act as a safety mechanism to avoid injection of expired contents 25 to the recipient.
[0018] In a specific example of the invention, a plurality of electrically conductive means 28 is in contact with, adhered to, or preferably embedded in, said plurality of flexible areas 23 , FIG. 6 a . Said plurality of electrically conductive means 28 are rather delicate and not as expandable or flexible as said plurality of flexible areas 23 . Furthermore, said plurality of electrically conductive means 28 are electrically connected to said processor 14 that detects its continuity as long as an electric current can pass through said plurality of electrically conductive means 28 . When said plurality of flexible areas 23 expand enough, said plurality of electrically conductive means 28 , in contact with, adhered to, or embedded in said plurality of flexible areas 23 , are physically torn apart and are no longer electrically conductive, FIG. 6 b . This design can be used to ascertain said container 18 is used only once, thereby preventing abuse by, for example, recreational drug users attempting to reuse said container 18 . When said container 18 comes in contact with said injecting device 1 in order to initiate extraction of its contents 25 , said processor 14 detects whether or not said plurality of electrically conductive means 28 are broken. If so, it does not allow the process of said content 25 extraction to proceed as one of the steps necessary for a successful content 25 injection into a recipient.
[0019] In a specific example of the invention, a barometer is placed inside said container 18 to detect and relay any change in pressure inside said container 18 to said processor 14 to evaluate the success of extraction of said contents 25 from said container 18 , FIG. 5 .
[0020] In another example of the invention, said container 18 includes a plurality of electrodes 21 being in electric contact with said content 2 , electrically connected to said processor 14 , and placed on the walls of and/or inside said container 18 , FIG. 5 . Said content 25 is electrically conductive, though it may exhibit a significant electrical resistance to an electrical current passing through it. Before extracting said content 25 , said processor 14 sends a signal to at least one said electrode 21 . If there is enough said content 25 in said container 18 , the electric signal passes through said electrically conductive content 25 to at least one other electrode 21 and back to said processor 14 , indicating of availability of adequate said content 25 for injection. Then, extraction of said content 25 may proceed. In case of inadequate said content 25 in said container 18 , not enough said content 25 is there to carry an electrical signal from at least one said electrode 21 to another, and no signal is received by said processor 14 , which in turn will not allow the extraction of said contents 25 to proceed or at least will warn of inadequate supply of said content 25 .
[0021] In another example of the invention, said container 18 includes a memory device 22 that stores certain electrical characteristics that the contents 25 of said container 18 have, for example, the electrical resistance that the contents 25 exhibit when two or more said electrodes 21 are placed a certain distance apart from each other, FIG. 5 . Two or more said electrodes 21 are placed on the walls of or inside said container 18 and in contact with its contents. This setup allows measuring the electrical resistance inherent in the content 25 of said container 18 . Said processor 14 will then verify that the measured electrical resistance of the contents 25 matches the electrical resistance stored by the manufacturer in said memory device 22 in said container 18 before it permits the injection to proceed. This design should prove beneficial in preventing abuse of the injecting device 1 , for example, by recreational drug users. Since the electrical characteristics of a recreational drug, that is filled in said container 18 after the original contents are emptied, are likely to be different than those of the original contents of said container 18 , said processor 14 will prevent the injection to proceed.
[0022] In a specific example of the invention, said container 18 is connected or connectable to a needle 8 with an inside canal 29 through which said contents 25 can pass to a said needle 8 tip that can reach and enter the recipient's body, FIG. 1 .
[0023] In a specific example of the invention, a plurality of said containers 18 can be held securely inside and released from said injection device 1 at will.
[0024] In a specific example of the invention, said plurality of containers 18 are generally shaped like a tube that contains a liquid. A plunger 15 is so positioned in said container 18 as to be able to force the liquid contents 25 towards and into said needle 8 , FIG. 1 .
[0025] In a specific example of the invention, said container 18 has a relatively elongated shape. Said container of injectable solution 18 has the capacity to receive and secure a plurality of said needles 8 so that the length of said plurality of needles 8 is generally perpendicular to the length of said container 18 . This design helps prevent spillage of said medicine from said cartridge due to shaking, vibration, and/or otherwise movement of said plurality of containers of injectable solution 18 and their contents, FIG. 1 .
[0026] The electrical environment inside the body is different than that outside the body. For example, the resistance to an electrical current passing through the body is different than that outside the body. In the following example of the invention, use is made of this phenomenon to ascertain successful needle penetration through the skin and into the body before said content 25 of said container of injectable solution 18 is ejected out of said plurality of needles 8 . A plurality of said needles 8 are at least partially electrically conductive and electrically connected to said processor 14 that senses any change in the electrical environment of said plurality of needles 8 , FIG. 1 . Said plurality of containers of injectable solution 18 are designed to accept said plurality of needles 8 . When said injecting device 1 is activated, it actuates said plurality of needles 8 to penetrate the skin and enter the body of the recipient. When said processor 14 senses the electrical environment at said plurality of needles 8 resembles the electrical environment inside the body, it sends a signal to initiate the injection of the contents of said plurality of containers 18 .
[0027] In a specific example of the invention, a portion of said plurality of needles 8 is electrically insulated 24 , FIG. 1 . That portion may include a span of said plurality of needles 8 starting from the tip of said needle 8 to a designated distance towards where said needle 8 meets said container of injectable solution 18 . This design assures that said needle 8 has penetrated the skin a designated distance before said processor 14 senses a change in the electrical environment by said needle 8 . Therefore said processor 14 senses a successful penetration of said needle 8 into the recipient's skin only after said needle 8 has penetrated into the skin a designated distance. It is only then that said processor 14 sends the signal that injection of the contents of said cartridge can start. Since there is limited or no pain perception associated with the injection, this safety mechanism is important because it ascertains that said needle 8 has penetrated the recipient's skin by a designated length, and the life saving contents of said container of injectable solution 18 are injected properly and not wasted outside the recipient's skin.
[0028] In a specific example of the invention, the content of said container of injectable solution 18 is electrically conductive. A plurality of electrodes 21 are placed on the walls of or inside said container of injectable solution 18 and/or said plunger 15 , and are in electrical contact with the contents 25 of said container of injectable solution 18 , FIG. 1 . The electrically conductive content 25 of said container of injectable solution 18 can transfer electrical impulses between, for example, one of the plurality of said needles 8 and a plurality of said electrodes 21 . This design can be applied, for example, to obviate the difficult task of attaching an electrical wire 20 directly to a plurality of said needles 8 in order to electrically connect them to said processor 14 . Instead, said electrical wire 20 can conveniently be electrically connected to a plurality of said electrodes 21 . Upon successful penetration of said plurality of needles 8 into the recipient's body, an electrical impulse signaling a change in the environment of said plurality of needles 8 travels from said plurality of needles 8 into the contents 25 of said container of injectable solution 18 and to said plurality of electrodes 21 . From there, an electrical wire 20 transfers the electrical impulse to said processor 14 .
[0029] In a specific example of the invention, said container of injectable solution 18 has the following safety mechanism to ensure that the process of extraction of said contents 25 is carried out properly and that the contents of said container 18 do not spill out useless through a defect or a fracture in the walls of said container 18 . Said container 18 walls includes a plurality of flexible areas 23 that are in contact with the inside pressure of said container 18 from the inside and are exposed to the outside of said container 18 from the outside, FIG. 2 . When said plunger 15 pushes the contents of said container of injectable solution 18 towards a plurality of said needles 8 during the process of injection, the pressure in the contents increases provided there are no fractures on the walls of said cartridge and the only exit available to the contents of said cartridge is through said plurality of needles 8 . The inside pressure increases because said content 25 cannot escape through said needle 8 as readily due to the small size of the canal 29 inside said needle 8 . This increase in pressure will, in turn, force said plurality of flexible areas 23 to bulge out while the contents are under pressure and exiting said plurality of needles 8 , FIG. 3 . The bulge in said plurality of flexible areas 23 activates a sensor (not shown) to send a signal to said processor 14 which in turn sends a signal to said injecting device 1 to continue the process of injection. If there is a fracture in any of the walls of said container of injectable solution 18 , the increase in pressure in the contents during the process of injection will be minimal or nonexistent. There will be minimal or no bulging on said plurality of flexible areas 23 Said injection device 1 will not be activated; and the process of injection will be discontinued to avoid spillage and waste of the contents of said container of injectable solution 18 . The recipient is notified of the failure of injection so he can procure the life-saving medicine in a different manner.
[0030] In a specific example of the invention, said container of injectable solution 18 has the following safety mechanism to make it difficult, if not impossible, for anyone to refill said container of injectable solution 18 . This safety mechanism can be implemented, for example, to prevent recreational drug users to use said injecting device 1 as a conduit to abuse drugs. Said container of injectable solution 18 is designed to have a general shape of a tube, in which said plunger 15 can travel to press the contents 25 of said container of injectable solution 18 into and out of said plurality of needles 8 . At least part of the inner surface of said container of injectable solution 18 is shape to allow the travel of said plunger 15 towards said plurality of needles 8 , but not in the opposite direction, FIG. 4 .
[0031] In a specific example of the invention, said container of injectable solution 18 includes a plurality of electric switches 19 , located preferably near said needle 8 , and electrically connected to said processor 14 , FIG. 1 . Said plurality of electric switches 19 are so positioned that as said needle 8 penetrates the recipient's body, said plurality of electric switches 19 get closer to the recipient's skin. At a designated distance from the skin, said plurality of electric switches 19 signal to said processor 14 indicating that said needle 8 has penetrated a designated distance into the recipient's body and the process of injecting said contents 25 can begin. Said processor 14 in turn allows the injection to proceed. Since there is limited or no pain perception associated with the injection, this safety mechanism is important in order to ascertain that said needle 8 has penetrated the recipient's skin by a designated length, and the life saving contents of said container of injectable solution 18 are injected properly and not wasted outside the recipient's skin.
[0032] In general, the size of a canal is inversely proportional to the speed of the fluid that travels inside it. In a specific example of the invention, use is made of this phenomenon to construct a backflow preventing mechanism to prevent blood and body fluids to travel through said needle 8 to said container 18 as in the following. Said needle 8 includes a plurality of segments, at some distance from said needle's 8 tip 30 , with a larger inside canal 31 than said canal 29 in the rest of said needle 8 , FIG. 7 . Backflow of blood and other body fluids from the recipient's body occur because of a momentary higher pressure in the body than inside said container 18 . If injection is administered at the correct site, said needle 8 does not pierce a major blood vessel and any backflow of blood through said needle 8 is rather limited and travels rather slowly. The presence of a plurality of segments of said needle 8 with said larger canal 31 hampers the progression of blood towards said container 18 as it takes longer to fill up said needle 8 segment with said larger canal 31 with blood. Before blood has a chance to reach said container 18 , said needle 8 is removed from the recipient's body. Therefore, the flow of blood to said container 18 is prevented. This design is helpful in situations where said container 18 has enough content 25 for two or more injections; and it is preferable not to introduce blood or other body fluids into said contents. In a specific example of the invention, a semi-pervious material 32 such as a sponge or bristles of a brush is placed inside said plurality of larger canals 31 to retard the free flow of fluids inside said plurality of larger canals 32 , in order to further help prevent the backflow of blood into said container 18 .
[0033] In a specific example of the invention, said container has the general shape of a tube and includes a content 25 with some electrical resistance. A plurality of electrodes 21 are placed at a certain distance from each other, and are in electrical contact with said content 25 and with said processor 14 . Said container 25 is positioned with respect to the gravity in such a way that the more said content 25 is there in said container 18 , the more said content 25 is in contact with said plurality of electrodes 21 , FIG. 5 . It is also known that the more said content 25 is contact with said plurality of electrodes 21 , the less electrical resistance is felt between said plurality of electrodes 21 . This fact can be used to measure the amount of said content 25 in said container 18 .
[0034] In a specific example of the invention, a plurality of said wires 20 are not directly connected to said processor 14 . Instead, they are connected to a plurality of connectors 33 that can in turn be connected to said processor 14 , FIG. 8 .
[0035] One skilled in the art will appreciate that the present invention can be practiced by other than the described embodiments, which are presented here for purposes of illustration and not of limitation, and the present invention is limited only by the claims that follow. | A container of an injectable solution is disclosed herein including various sensors, electrodes, a memory device, and other features that monitor the process of extraction or injection of the content of the container to ensure it is completed successfully in an automated manner, such as in an automatic injecting device. | 0 |
BACKGROUND OF THE INVENTION
The present invention relates to an optical amplifier, light source module and optical system.
In general, the optical amplifier can amplify optical signals by using optical fibers doped with a rare-earth element such as erbium (Er), without light-electricity conversion.
FIG. 10 is a block diagram of an optical amplifier FA 2 constructed according to the prior art. As shown in this figure, the optical amplifier FA 2 has a pumping light source 1 configured to output a pumped light and an amplifier unit 3 configured to receive the pumped light from the pumping light source 1 through a first optical fiber 2 and amplify and output the optical signal inputted into the first optical fiber 2 .
The pumping light source 1 may be in the form of a semiconductor laser module (LD module) and designed to output a pumped light of 980 nm band, for example.
The first optical fiber 2 may be in the form of an optical fiber doped with erbium (Er), for example, when an optical signal of 1550 nm band is to be amplified.
The amplifier 3 comprises an input terminal 4 configured to receive the optical signal, an output terminal 5 configured to output the amplified optical signal, first and second isolators 6 , 7 configured to propagate the optical signal only in a direction from the input terminal 4 to the output terminal 5 while preventing the optical signal from transmitting in the opposite direction, and an optical multiplexer 8 which may be in the form of an optical coupler for multiplexing the optical light transmitting through the first optical fiber 2 with the pumped light supplied from the pumping light source 1 through the second optical fiber 9 .
The optical signal from the input terminal 4 is inputted into the optical multiplexer 8 through the first optical fiber via the first isolator 6 . On the other hand, the pumping light from the pumping light source 1 is inputted into the optical fiber 2 through the second optical fiber 9 and optical multiplexer 8 .
The optical fiber 2 is pumped by the inputted pumping light to amplify the optical signal which is in turn outputted from the output terminal 5 through the optical multiplexer 8 and second isolator 7 .
SUMMARY OF THE INVENTION
An optical amplifier of the present invention comprises a pumping light source configured to output a pumping light, an amplifier unit configured to receive the pumping light from said pumping light source and amplify an optical signal that passes therethrough, and an optical fiber disposed between said pumping light source and said amplifier unit, said optical fiber including an optical filter that is configured to attenuate the optical signal from said amplifier unit.
A light source module of the present invention comprises a light source configured to output a laser beam, an optical fiber configured to have said laser beam propagate therethrough, and an optical filter disposed in said optical fiber and configured to attenuate light having a first wavelength band that is different from a second wavelength band in said laser beam.
An optical system of the present invention comprises a first optical device configured to emit a light having a first wavelength band, a second optical device configured to emit a light having a second wavelength band, means for connecting said first and second optical devices, and an optical part configured to propagate the light having the second wavelength band from said second optical device to said first optical device through said connecting means, said optical part being configured to prevent the light having the first wavelength band from said first optical device to enter said second optical device through said connecting means and also to return from said connecting means or said second optical device back to said first optical device.
A method for generating pump light for an optical amplifier of the present invention comprises steps of;
emitting a light in a first optical bandwidth from a first optical device;
emitting another light in a second optical bandwidth from a second optical device;
passing the another light through a connecting portion from said first optical device to said second optical device, including sub-steps of,
preventing light in the first optical bandwidth from said first optical device from entering said second optical device, and also returning to said first optical device from at least one of said second optical device and the connecting portion.
A light source for an optical amplifier of the present invention comprises means for emitting a light in a first optical bandwidth, means for emitting another light in a second optical bandwidth, means for passing the another light to said means for emitting a light, including, means for preventing light in said first optical bandwidth from entering said means for emitting the another light, and also returning to said means for emitting a light from at least one of said means for emitting the another light and said means for passing.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram of an optical amplifier constructed according to one embodiment of the present invention.
FIG. 2 (A) illustrates a process of producing LPG which is usable in the optical amplifier according to the embodiment of the present invention; and
FIG. 2 (B) illustrates the operation of LPG.
FIG. 3 shows two examples of a protecting member for protecting a grating portion in an optical filter: (A) and (B) are perspective views thereof; (C) and (D) are side cross-sectional views thereof; and (E) and (F) are front cross-sectional view thereof, respectively.
FIG. 4 is a graph illustrating the transmission characteristics obtained when LPG is mounted on the tip of a pigtail fiber in a 980 nm band LD (laser diode) module.
FIG. 5 (A) is a block diagram of an optical filter usable in an optical amplifier according to another embodiment of the present invention; and
FIG. 5 (B) is a graph illustrating the relationship between the transmissivity and the wavelength of the optical filter.
FIG. 6 is a graph illustrating the transmission characteristics obtained when 11 LPG's each of 2 mm length are connected directly with one another.
FIG. 7 (A) is a graph illustrating the relationship between the grating cycle of the optical fiber and the coupling wavelength of the optical fiber; and
FIG. 7 (B) is a graph illustrating a loss of light transmission created in the optical fiber when the grating cycle of the optical fiber is about 440 nm.
FIG. 8 (A) is a graph illustrating the loss of transmission in a sample S 1 ; and
FIG. 8 (B) is a graph illustrating the loss of transmission in another sample S 2 .
FIG. 9 illustrates a process of experiment which was performed by the inventors.
FIG. 10 is a block diagram of an optical amplifier constructed according to the prior art.
DETAILED DESCRIPTION
Several embodiments of the present invention will now be described with reference to the drawings, in comparison with the prior art.
In the optical amplifier FA 2 of the prior art shown in FIG. 10, a light escaped from the amplifier 3 may reach the pumping light source 1 through the second optical fiber 9 . The light escaped out of the amplifier 3 may cause noise components disturbing the light emitting action in the pumping light source 1 . In addition, the escaped light may be reflected at the reflecting point within the pumping light source 1 (e.g., one terminal of the optical fiber) to form a reflected returning light which may cause noise components disturbing the amplification in the amplifier 3 .
Form experiments, the inventors have found that the reflectivity in the light having its wavelength of 1545 nm band in a pumping light source 1 consisting of a 980 nm band LD module varied between −5 dB and −13 dB depending on the type of machine. This is because many 980 nm band LD modules were designed taking no account of the reflection particularly in 1550 nm band. Thus, the amount of reflected light returned to the amplifier 3 will also vary. It is thus very difficult to regulate the amplification of light. If the design of the LD module or a laser chip within the LD module is changed taking account of the reflection in 1550 nm band, the other characteristics of the LD module (e.g., output power or the like) will be restricted.
There was thus proposed a technique which prevented the returned light from the amplifier 3 from passing through the second optical fiber 9 by an optical isolator formed between the pumping light source 1 and the optical multiplexer 8 . Such a technique will be referred to the first prior art.
There was also proposed another technique by which a WDM coupler is provided between the pumping light source 1 and the optical multiplexer 8 , a port of that WDM coupler outputting the returned light from the amplifier 3 being connected to a terminator for terminating the reflection. This technique will be referred to the second prior art.
However, the optical isolator used in the first prior art is expensive and larger in size. The optical amplifier FA 2 will be produced with an increased cost and increased in size. A holder for holding the optical parts of the optical isolator and other members are made of iron alloy. Since the iron alloy absorbs the light components in 980 nm band, a problem is raised in that the optical isolator cannot be used when the pumping light source 1 of 980 nm band is to be used.
Since the WDM coupler used in the second prior art requires the configuration of optical fiber that is 2×1, the management of optical fiber in the interior of the device becomes inconvenient with increase of points to be fused. Moreover, it is substantially essential that the WDM coupler includes a reinforcing sleeve. This correspondingly increases the entire volume. If the rigid sleeve is larger in diameter, it is also inconvenient to house or handle the sleeve within the device.
Thus, there is always the possibility raising the similar problems in an optical system in which optical devices such as amplifier, pumping light source and so on are connected to one another through connection means such as optical fibers or the like.
On the contrary, one embodiment of the present invention as shown in FIG. 1 is characterized by that the second optical fiber 9 connecting between the pumping light source 1 and the amplifier unit 3 includes an optical filter 10 . The optical filter 10 can attenuate the light from the amplifier 3 by causing it to emit to the clad mode in the second optical fiber 9 . In addition, a pumping light source module 11 is formed by the pumping light source 1 and the optical filter 10 .
The optical filter 10 may be in the form of a long-period fiber grating (LPG) having refractive index stripes in which the refractive index in the core of the optical fiber periodically varies in the direction of optical axis. LPG has its grating period about 100 times larger than that of a short-period grating for the normal reflection, that is, between about 100 μm and about 1000 μm.
When LPG is to be produced, a long-period mask 14 is first placed on the top of an optical fiber 13 having a core 12 which is made of germanium-doped quartz, as shown in FIG. 2 (A). The long-period mask 14 may be formed by forming a plurality of thin slit on a metal sheet with a predetermined spacing or by depositing a multi-layer dielectric film on a quartz glass plate. Ultra-violet rays 15 are then irradiated onto the long-period mask 14 , for example, from an argon laser. The core 12 irradiated by the ultra-violet rays 15 is increased in refractive index to form refractive-index stripes 12 a . Thus, LPG will be formed.
This LPG is then used in the optical filter 10 , so that a pumping light of λ2 wavelength (e.g., 980 nm band) from the pumping light source 1 passes through the waveguide of the optical fiber while the optical signal of λ1 wavelength (e.g., 1550 nm band) escaped from the amplifier 3 is emitted and attenuated to the clad mode of the optical fiber (see FIG. 2 (B)). Even though the light of λ1 wavelength is reflected and returned from the pumping light source 1 , it will be again attenuated by the optical filter 10 . Therefore, the amount of light returned back to the amplifier 3 can highly be reduced.
The grating period will now be described. FIG. 7 (A) is a graph illustrating the relationship between the grating period and the coupling wavelength in the optical fiber.
Characteristic lines a to j in FIG. 7 (A) show wavelengths at each of which its loss of light transmission peaks. In this specification, therefore, the above coupling wavelengths will be referred to peak wavelengths of light transmission loss in the first through N-th order modes (wherein N=10). In FIG. 7 (A), the characteristics lines a to j respectively represent the peak wavelengths of light transmission loss in the first through tenth modes in the described order starting from the right side of this figure. These values shown in FIG. 7 (A) were measured at 25° C.
As will be apparent from FIG. 7 (A), for example, if the grating period (fiber grating period) forming an optical fiber is between 150 μm and about 580 μm, the peak wavelengths of light transmission loss in plural order modes can be formed within a range of wavelength between 0.9 μm (900 nm) and 1.6 μm (1600 nm). Moreover, the peak wavelength in each of the first through N-th order modes can freely be determined by changing its fiber grating period.
For example, if the grating period is about 440 nm, the peak wavelengths of light transmission loss in the first through fifth order modes can be formed, as shown in FIG. 7 (B). If a mode is set to be the fourth order mode, the peak wavelengths of light transmission loss in the fourth order mode becomes equal to about 1510 nm. The peak wavelengths of light transmission loss in the next mode (i.e., the fifth order mode) becomes longer than 1610 nm (about 1640 nm in this figure). In any zone having its longer wavelength (e.g., from 1540 nm to 1610 nm), the difference between the maximum and minimum values in the loss of light transmission is smaller than 0.5 dB. This substantially flattens the characteristic curve. In such LPG's, the jacket in the optical fiber is stripped to expose the glass area when the grating is to be produced. If the exposed portion is again covered with the jacket through a recoat technique, however, such an optical fiber can be housed or handled in the same manner as in the conventional optical fibers, since the appearance of the recoated optical fiber is not different from those of the conventional optical fibers.
FIGS. 3 (A) and (B) shows different examples of a protecting member 17 for protecting the grating portion 17 of the optical filter 10 . The protecting member 17 shown in FIG. 3 (A) is applied as shown in FIGS. 3 (C) and (E) while the protecting member 17 shown in FIG. 3 (B) is applied as shown in FIGS. 3 (D) and (F). As shown in FIG. 3, it is preferred in LPG that the grating portion 16 is housed in the protecting member 17 made from quartz. Thus, the grating portion 16 can be prevented from being externally influenced by the protecting member 17 to maintain the characteristic of light transmission loss.
The protecting member 17 may be formed into a cylindrical configuration and with a groove 17 a for holding the grating portion 16 , as shown in FIGS. 3 (A) and (E). The protecting member 17 may also be formed by a pair of split sleeves which can be abutted with each other to form a cylindrical configuration, as shown in FIGS. 3 (B) and (F). As shown in FIGS. 3 (C) and (D), the grating portion 16 is bonded to the opposite ends of each of the protecting member 17 through an adhesive 18 .
FIG. 4 is a graph illustrating the characteristic of transmissivity when LPG is mounted on the tip of a pig-tail fiber in a 980 nm band LD module. The LPG is 22 mm length and has its central wavelength (or peak wavelength of light transmission loss) equal to 1545 nm.
The characteristic of transmissivity of the LPG shown in FIG. 4 relates to the transmission of light in one direction. Since the returned light from the pumping light source 1 will passes through the LPG at twice, the transmissivity will be two times larger than that of FIG. 4 in conversion into dB.
For example, the transmissivity may be equal to or lower than −6 dB in the range of 12 nm between 1539 nm and 1551 nm. Even if an LD module having the maximum reflectivity within this range of wavelength is used, a loss
−5 dB+ (−6 dB ) X 2=−17 dB
will be obtained. The entire system will be improved even by 12 dB.
The inventors had prepared two long-period grating (LPB) samples in which the central wavelengths (or peak wavelengths of light transmission loss) thereof had been about 1545 nm. These samples will be referred to sample S 1 and S 2 . The two samples had been used to measure the light reflectivity relating to the light of 1550 nm band wavelength.
The losses of transmission in the samples S 1 and S 2 are shown in FIGS. 8 (A) and (B), respectively. The losses of transmission in the samples S 1 and S 2 in the 1550 nm band were about −15 dB, as shown in FIG. 8 .
FIG. 9 illustrates a process of experiment carried out by the inventors. As shown in FIG. 9, an optical coupler 19 having first to fourth ports P 1 to P 4 is provided. A light from a signal light source 20 in 1550 nm band is inputted into the first port P 1 of the optical coupler through an optical isolator 21 . The inputted light is then branched into two light parts which are in turn outputted from the second and fourth ports P 2 , P 4 , respectively. A light from a 980 nm band LD module 22 is inputted into the second port P 2 of the optical coupler 19 . Similarly, this light is divided and outputted from the first and third ports P 1 , P 3 , respectively.
The light outputted from the third port P 3 of the optical coupler 19 is then inputted into an optical output meter 24 through an optical isolator 23 . The light outputted from the fourth port P 4 of the optical coupler 19 is terminated without reflection by an optical isolator 25 . In FIG. 10, L denotes an optical fiber.
The optical output meter 24 was used to measure the light reflectivity of the 980 nm band LD module in 1550 nm band before and after the long-period grating samples S 1 and S 2 were mounted between the 980 nm band LD module 22 and the optical coupler 19 (see FIGS. 10 (A) and (B)).
TABLE 1
Before Mounted
After Mounted
Difference
Sample S1
−10.5
dB
−37.6
dB
−27.1
dB
Sample S2
−9.8
dB
−36.2
dB
−26.4
dB
Table 1 shows the results of experiment. As will be apparent from Table 1, the sample S 1 shows an improvement by 27.1 dB while the sample S 2 indicates an improvement by 26.4 dB. When the long-period grating is mounted between the 980 nm band LD module 22 and the optical coupler 19 , it is therefore found that the light reflectivity of the 980 nm band LD module 22 in 1550 nm band is greatly reduced.
Since this embodiment of the present invention is configured that the optical filter 10 configured to emit and attenuating the light from the amplifier 3 to the clad mode of the second optical fiber 9 is located in the second optical fiber 9 connecting between the pumping light source 1 and the amplifier 3 , it can be prevented that the light escaped out of the amplifier 3 reaches the pumping light source 1 through the second optical fiber 9 . Moreover, even though the light is reflected at the reflecting point in the pumping light source 1 (e.g., the end of the optical fiber), the reflected light can be prevented from reaching the amplifier 3 . As a result, noise components that may disturb the light-emission and amplification in the pumping light source 1 and amplifier 3 can be reduced to improve the reliability in the optical amplifier FA 1 and pumping light source module 11 .
If the optical filter 10 is LPG, the system can be reduced in size and manufacturing cost since the fiber grating is very small and inexpensive with the sleeve portion being not frequently required. Therefore, the present invention can provide the optical amplifier, pumping light source module and optical system in which the optical fiber can more easily be managed without increase of points to be fused and which are superior in housing and handling properties.
FIG. 5 (A) is a block diagram of an optical filter 10 usable in an optical amplifier FA 1 that is constructed according to another embodiment of the present invention while FIG. 5 (B) is a graph illustrating the characteristic of transmissivity in such an optical filter 10 .
As shown in FIG. 5 (A), this second embodiment is characterized by that three LPG's 10 a , 10 b and 10 c respectively having central wavelengths of 1535 nm, 1545 nm and 1555 nm are connected in series to one another. In this case, the net transmissivity is as shown in FIG. 5 (B). The width of wavelength having a transmissivity equal to or higher than −6 dB can be enlarged to be equal to or larger than 30 nm.
FIG. 6 is a graph illustrating a characteristic of transmissivity when 11 LPG's each having a length of 2 mm are connected in series to one another. At this time, the central wavelengths of the 11 LPG's were set to exist between 1535 and 1555 nm with intervals of 2 nm. The total length of the LPG array is 22 nm as in FIG. 4 . Such a multi-stage connection can enlarge the range of wavelength for obtaining the transmissivity of −6 dB in the same LPG length to 17 nm between 1536 nm and 1553 nm. The increase in the number of LPG stages is equivalent to that the grating period is continuously varied from one side of an LPG to the other side (which can be referred to a so-called chirped grating). The chirped grating is effective for reducing the reflectivity over a widened band.
The present invention is not limited to the aforementioned embodiments, but may be carried out in any of various changed or modified forms without departing from the spirit and scope of the invention as claimed in the appending claims.
Although the aforementioned embodiments have been described as to the optical filter 10 of LPG, the present invention may similarly utilize any means unless it forms the clad mode. For example, the present invention can provide the same advantage even by formation of a reflection type secondary grating.
Moreover, the present invention may control the core profile of an optical fiber to give the optical fiber a predetermined bending without use of the grating. When the optical fiber has a bending, the refractive index in the core may vary. This provides such an advantage that the light of 980 nm band can substantially pass through the optical fiber, but the light of 1550 nm joints to the emission mode. Since the light is taken out from the side of shorter wavelength if the optical fiber is bent, such a structure may be applied to a case where the light from the side of shorter wavelength is to be attenuated.
The light of emission mode will float in the clad mode, but not joint to the waveguide mode. If a light included in the clad mode must also be considered, a material that can absorb the light from the amplifier 3 may be located between the clad and the jacket to absorb the clad mode light. | An optical amplifier of the present invention comprises a pumping light source configured to output a pumping light, an amplifier unit configured to receive the pumping light from said pumping light source and amplify an optical signal that passes therethrough, and an optical fiber disposed between said pumping light source and said amplifier unit, said optical fiber including an optical filter that is configured to attenuate the optical signal from said amplifier unit. | 7 |
RELATED APPLICATION DATA
[0001] This application is related to Applicants' patent applications entitled METHOD AND APPARATUS FOR ESTABLISHING USAGE RIGHTS FOR DIGITAL CONTENT TO BE CREATED IN THE FUTURE (Attorney Docket No. 111325-68), DEMARCATED DIGITAL CONTENT AND METHOD FOR CREATING AND PROCESSING DEMARCATED DIGITAL WORKS (Attorney Docket No. 111325-62), METHOD AND APPARATUS FOR DYNAMICALLY ASSIGNING USAGE RIGHTS TO DIGITAL WORKS (Attorney Docket No. 111325-66), METHOD AND APPARATUS FOR ASSIGNING CONDITIONAL OR CONSEQUENTIAL RIGHTS TO DOCUMENTS AND DOCUMENTS HAVING SUCH RIGHTS (111325-64), and METHOD AND APPARATUS FOR HIERARCHICAL ASSIGNMENT OF RIGHTS TO DOCUMENTS AND DOCUMENTS HAVING SUCH RIGHTS (111325-65), which are being filed concurrently herewith, and are incorporated herein by reference in their entirety.
BACKGROUND
[0002] The invention relates generally to distribution of digital works and more specifically to digital works having usage rights that can be transferred to others and a method and apparatus for effecting such a transfer.
[0003] One of the most important issues impeding the widespread distribution of digital works or documents (i.e. documents in forms readable by computers), via electronic means, and the Internet in particular, is the current lack of ability to enforce the intellectual property rights of content owners during the distribution and use of digital works. Efforts to resolve this problem have been termed “Intellectual Property Rights Management” (“IPRM”), “Digital Property Rights Management” (“DPRM”), “Intellectual Property Management” (“IPM”), “Rights Management” (“RM”), and “Electronic Copyright Management” (“ECM”), collectively referred to as “Digital rights management (DRM)” herein. There are a number of issues to be considered in digital rights management: authentication, authorization, accounting, payment and financial clearing, rights specification, rights verification, rights enforcement, and document protection for example. U.S. Pat. Nos. 5,530,235, 5,634,012, 5,715,403, 5,638,443, and 5,629,980 disclose DRM concepts addressing these issues and the disclosures thereof are incorporated herein by reference.
[0004] In the world of printed documents, a work created by an author is usually provided to a publisher, which formats and prints numerous copies of the work. The copies are then sent by a distributor to bookstores or other retail outlets, from which the copies are purchased by end users. While the low quality of copying and the high cost of distributing printed material have served as deterrents to unauthorized copying of most printed documents, it is far too easy to copy, modify, and redistribute unprotected digital works. Accordingly, some method of protecting digital works is necessary to make it more difficult to copy them without authorization.
[0005] Unfortunately, it has been widely recognized that it is difficult to prevent, or even deter, people from making unauthorized distributions of digital works within current general-purpose computing and communications systems such as personal computers, workstations, and other devices connected over communications networks, such as local area networks (LANs), intranets, and the Internet. Many attempts to provide hardware-based solutions to prevent unauthorized copying have proven to be unsuccessful. The proliferation of high band-width “broadband” communications technologies will render it even more convenient to distribute large documents electronically, including video files such as full length motion pictures, and thus will remove any remaining deterrents to unauthorized distribution of digital works. Accordingly, DRM technologies are becoming a high priority.
[0006] Two basic DRM schemes have been employed to attempt to solve the document protection problem: secure containers and trusted systems. A “secure container” (or simply an encrypted document) offers a way to keep document contents encrypted until a set of authorization conditions are met and some copyright terms are honored (e.g., payment for use). After the various conditions and terms are verified with the document provider, the document is released to the user in clear form. Commercial products such as IBM's CRYPTOLOPES™ and InterTrust's DIGIBOXES™ fall into this category. Clearly, the secure container approach provides a solution to protecting the document during delivery over insecure channels, but does not provide any mechanism to prevent legitimate users from obtaining the clear document and then using and redistributing it in violation of content owners' intellectual property.
[0007] Cryptographic mechanisms are typically used to encrypt (or “encipher”) documents that are then distributed and stored publicly, and ultimately privately deciphered by authorized users. This provides a basic form of protection during document delivery from a document distributor to an intended user over a public network, as well as during document storage on an insecure medium.
[0008] In the “trusted system” approach, the entire system is responsible for preventing unauthorized use and distribution of the document. Building a trusted system usually entails introducing new hardware such as a secure processor, secure storage and secure rendering devices. This also requires that all software applications that run on trusted systems be certified to be trusted. While building tamper-proof trusted systems is a real challenge to existing technologies, current market trends suggest that open and untrusted systems such as PC's and workstations using browsers to access the Web, will be the dominant systems used to access digital works. In this sense, existing computing environments such as PCs and workstations equipped with popular operating systems (e.g., Windows™, Linux™, and UNIX) and rendering applications such as browsers are not trusted systems and cannot be made trusted without significantly altering their architectures. Of course, alteration of the architecture defeats a primary purpose of the Web, i.e. flexibility and compatibility.
[0009] U.S. Pat. No. 5,634,012, the disclosure of which is incorporated herein by reference, discloses a system for controlling the distribution of digital works. Each rendering device has a repository associated therewith. A predetermined set of usage transaction steps define a protocol used by the repositories for carrying out usage rights associated with a work. Usage rights are encapsulated with the content of the digital work or otherwise associated with the content to travel with the content. The usage rights can permit various types of use such as, viewing only, use once, distribution, and the like. Rights can be granted based on payment or other conditions.
[0010] Current DRM techniques do not provide the flexibility of distribution that is possible with conventional printed documents. For example, the purchaser of a copy of a book generally can give that same copy to another, trade that copy, or sell that copy without violating the rights of the copyright holder. However, DRM techniques do not provide a flexible means for accomplishing analogous distribution of digital works without diminishing the control over the digital work by the content owner.
SUMMARY OF THE INVENTION
[0011] It is an object of the invention to increase the flexibility of distribution of digital content. A first aspect of the invention is a method of transferring digital works from one user to another user comprising, associating usage rights, transfer permission information, and a current user identification flag with digital content, distributing a digital work including the content to a first user in accordance with the usage rights, setting the current user identification flag to correspond to the first user, and transferring the digital work to a second user and setting the current user identification flag to correspond to the second user.
[0012] A second aspect of the invention is a system for transferring digital works from one user to another user. The system comprises digital content, a usage rights module containing usage rights information associated with the content for a user, a transfer permission module containing transfer permission information for the content, a current user identification module containing identity information indicating the identity of the user, and means for manipulating the current user identification module to change the identity information.
BRIEF DESCRIPTION OF THE DRAWING
[0013] The invention will be described through a preferred embodiment and the attached drawing in which:
[0014] [0014]FIG. 1 is a block diagram of a distribution system in accordance with the preferred embodiment;
[0015] [0015]FIG. 2 is a schematic illustration of the relationship between a digital work and the distribution server of the preferred embodiment; and
[0016] [0016]FIG. 3 is a flowchart of an exchange method of the preferred embodiment.
DETAILED DESCRIPTION
[0017] [0017]FIG. 1 is a block diagram of a system for the electronic distribution of digital works, which may include correspondence, books, magazines, journals, newspapers, other papers, software, audio and video clips, and other files objects and the like in accordance with the preferred embodiment. The phrase “digital work” as used herein refers to any type of element having content in computer readable form. “Content” as used herein refers to the viewable or otherwise usable portion of a digital work. Author 110 creates original content 112 and passes it to distributor 120 for distribution. Ordinarily, author 110 is the creator of the content. However, the term “author” as used herein can be the creator, owner, editor, or other entity controlling the content or an agent (e.g. a publisher) of one of those entities. Also author 110 may distribute documents directly, without involving another party as distributor 120 and thus the author and distributor may be the same entity. However, the division of functions set forth in FIG. 1 is more efficient, as it allows author 110 to concentrate on content creation and not the administrative functions of distribution. Moreover, such a breakdown facilitates economies of scale by permitting distributor 120 to associate with a number of authors 110 .
[0018] Distributor 120 distributes digital works, such as works 200 and 202 to users 130 and 132 upon request. The digital works can be distributed as a document containing the content and associated usage rights in encrypted form. Distributor 120 encrypts the works with a public key and then encrypts the public key with a private key corresponding to user 130 or 132 . Thus the encrypted work is customized solely for the particular user 130 or 132 . Users 130 and 132 are then able to use their private key to unencrypt the public key and use it to unencrypt and view the content of the work 200 or 202 . Of course, there can be any number of users and any number of digital works. For the sake of simplicity, there are two users and two digital works in the preferred embodiment.
[0019] Payment for the work is passed from user 130 or 132 to distributor 120 by way of clearinghouse 150 which collects requests from user 130 and 132 and from other users who wish to sue a particular content. Clearinghouse 150 also collects payment information, such as debit transactions, credit card transactions, or other known electronic payment schemes, and forwards the collected payments as a payment batch to distributor 120 . Of course, clearinghouse 150 may retain a share of the payment as a fee for the above-noted services. Distributor 120 may retain a portion of the batch payment from clearinghouse 150 for distribution services and forward a payment (for example royalties) to author 110 . Distributor 120 may compile a bundle or batch of user requests for a single work before distributing the work. In such a case, a single instance of the encrypted work can be generated for unencryption by all of the requesting users 130 . Clearinghouse 150 also maintains various records regarding ownership and usage rights as described in detail below.
[0020] Each time user 130 or 132 requests (or uses) content of a work, an accounting message can be sent to clearinghouse 150 which ensures that each request by user 130 matches with a document sent to user 130 or 132 by distributor 120 . Accounting information is received by clearinghouse 150 directly from distributor 120 . Any inconsistencies can be used adjust the payment batches made to distributor 120 accordingly. This accounting scheme is operative to reduce the possibility of fraud in electronic distribution and to handle any time-dependent usage permissions that may result in charges that vary, depending on the duration or other extent of use. Clearinghouse 150 includes server 250 (see FIG. 2), a programmable general purpose computer for example. Server 250 includes a processor which runs rights transfer module 252 in the form of software code. The function of rights transfer module 252 is described in detail below.
[0021] [0021]FIG. 2 illustrates the mechanism for facilitating the transfer of usage rights in accordance with the preferred embodiment. Under the assumption that digital work 200 has been distributed to user 130 and that digital work 202 has been distributed to user 132 , an example of the preferred embodiment is described below. Digital work 200 includes content 210 and can be stored in a computer memory, such as a memory in a user device used for viewing content 210 . For example, the user device can be a personal computer, and ebook reader, a personal digital assistant (PDA), or the like. In the example of the preferred embodiment, user 130 has a right to use content 210 , and user 132 has a right to use content 310 . Content 210 and content 310 have usage rights 212 and 312 respectively associated therewith and users 130 and 132 have respective licenses to use content 210 and content 310 in accordance with the usage rights.
[0022] If user 130 and user 132 desire to exchange their respective rights in content 210 and 310 , i.e. user 130 desires rights to use content 310 and user 132 desires rights to use content 210 , the exchange can be effected using current user ID flag module 216 of rights transfer module 252 to track the current user of content 210 and 310 . Of course, the right to exchange is an additional right which has already been awarded and which is tracked in transfer permissions module 214 . The exchange of usage rights may involve some fee, paid by user 130 to user 132 or vice versa. Rights transfer module 252 keeps track of this fee/percentage, and notifies the original content owners, who may be entitled to a percentage of the fee which was paid by a user (based on the license agreements between the users and the content owners). The price can be set using a predetermined, on-spot, or dynamic scheme, such as auction or stock-exchange. The exchange right/fee schedules can be attached to the content or other rights (physically, or by a pointer associated with a remote schedule). Current user ID flag module includes a database structure having a current user flag for each of works 200 and 202 . Such a flag can be an ID number or any other indication of the current authorized user. The exchange may involve more than two users, in which case current user ID flag module 216 can keep track of rights, fees, percentages, content owners, and current users (an exchange forum, similar to a stock exchange setting).
[0023] [0023]FIG. 3 illustrates an exchange method in accordance with the preferred embodiment. When users 130 and 132 wish to exchange usage rights to content, a request is sent to server 250 from one of the users in step 400 . Rights transfer module 252 checks transfer permission module 214 to ascertain if the requested transfer has been authorized by the content owner or other applicable party in step 402 . If such permission has been granted, transfer permission module 214 manipulates current user ID flag module 216 to reflect the exchange in current users of the content, i.e. user 130 because the current user of content 310 and user 132 becomes the current user of content 210 , in step 404 .
[0024] Subsequently, in step 406 , transfer permissions module 214 changes the usage rights 212 and 312 to prohibit use by users 130 and 132 of content 210 and 310 respectively and to permit the same use by the new user 132 and 13 respectively. Finally, in step 408 , works 200 and 202 are exchanged between users 130 and 132 with the new usage rights 212 and 312 respectively. Alternatively, works 200 and 202 can be redistributed from distributor 120 or clearinghouse 150 to users 130 and 132 . In any case, clearinghouse 150 can track all transactions, usage rights, current user data, and the like.
[0025] The preferred embodiment can be adapted to an auction, as well. The right to auction can be awarded by the original content owner to the user, and the user can exercise this right, provided that the price limitations, time limitations, geographical limitations, and usage limitations (specified by the content owner) are followed. The price or range of price or percentages/fees/commissions can be predetermined, or can be dynamic, for example, using the market or other factors, for example, set by the current user. To encourage the exchange between friends, peer-to-peer distribution, or super-distribution, point or other rewards can be awarded to the user. Super-distribution can be done through e-mail or instant-messaging, using address books or “buddy lists.”
[0026] The preferred embodiment can be used for version control, for updating/replacing (or providing patches or corrections for) content. The preferred embodiment can process returned content by a user, to obtain a refund, if the nature of the content permits and the owner of the content wishes to give this option to the user as an added usage right.
[0027] Instead of trading usage rights, user 130 may wish to merely grant remaining usage rights to user 132 . For example, if user 130 buys a license to use software, and later wants to transfer the license to user 132 , User 130 can transfer the usage rights to user 132 in a manner similar to the exchange described above. In such a case, clearinghouse 150 can collect an electronic signature from user 132 and send any appropriate notices, such as a terminating notice to user 130 . If the content owner requires a fee for such a transfer, clearinghouse 150 can effect the fee transfer. In addition, a certification for disablement or destruction of the of the software in position of user 130 can be issued automatically by clearinghouse 150 and sent to the content owner or authorized representative.
[0028] Alternatively, user 130 may have the right to use content for a specific time period. User 130 then uses the content for a portion of the allowed time. However, before the expiration time period, user 130 can transfer the balance of remaining allowable time to user 132 . This can be effected in the manner described above. Of course this right also can be assigned to user 130 by the original content owner.
[0029] In the case of accessing (or storing) information from multiple servers, clearinghouse 150 can keep track of all servers for an optimized accessing scheme. For example, tags can be used for identification and referral to a specific server for edge delivery of content on the Internet or any other network (as opposed to centralized content delivery), to solve the first-mile-bottleneck problem (related to traffic on the network).
[0030] The particular modules of the preferred embodiment have been described by functionality. However, the modules and need not be separate entities, such as separate files or even blocks of code. Also, the fucntions of the various modules can be mixed or combined. The various functions can be accomplished by any combination of software and/or hardware. For example, the invention can be implemented on one or more general purpose programmable computers, such as personal computers, servers, or the like. Date transfer can be accomplished using HTTP over the Internet or in any other manner.
[0031] Any usage rights can be transferred traded, or assigned. The various data and files can be stores at any location and linked in an appropriate manner. For example, the content and usage rights need not be stored together. Accordingly, “associated” as used herein refers broadly to an established correspondence such as a call or a link, or other relationship. The digital works can be transferred directly form user to user or through a centralized system. The usage rights include all usage rights that can be expressed by the XrML™ rights language and other rights grammar.
[0032] The invention has been described trough a preferred embodiment. However, various modifications can be made without departing from the scope of the invention as defined by the appended claims and legal equivalents. | A method and apparatus for facilitating transfer of usage rights for digital content. The system comprises digital content, a usage rights module containing usage rights information associated with the content for a user, a transfer permission module containing transfer permission information for the content, a current user identification module containing identity information indicating the identity of the user, and means for manipulating the current user identification module to change the identity information. The content can be transferred form one user to another and the current user identification module can be manipulated to reflect the current user and to permit the current user to have usage rights in the document. | 8 |
FIELD OF THE INVENTION
The present invention relates generally to railway equipment. More particularly, the present invention relates to innovative designs and use of switch rods to prevent derailment of a train that reverses through a previously trailed railroad switch.
BACKGROUND OF THE INVENTION
A railroad switch is a well-known mechanical installation that enables railway trains to be guided from one set of tracks to another set of tracks.
FIGS. 1A-1B show a typical railroad switch located at the intersection of main tracks 101 and secondary tracks 102 . The railroad switch has switch points 104 which are mechanically linked so that they move together when toggled from one position to another. As a train approaches the railroad switch along the main tracks 101 and in the facing-point direction, the train wheels are guided along the route determined by which of the two switch points 104 is connected to the track facing the switch. If the left point is connected, as shown in FIG. 1A , then the left wheels of the train will be guided along the rail of that point, and the train will diverge to the right onto the secondary tracks 102 . If the right point is connected, as shown in FIG. 1B , then the right wheels will be guided along the rail of that point, and the train will continue along the main tracks 101 . The mechanical link between the switch points 104 ensures that only one of them may be connected to the facing track at any given time.
In FIG. 1A , if the train travels on the secondary tracks 102 but in the trailing-point direction, when the left point of the switch is connected, the train will continue onto the main tracks 101 without any issue. However, if the train travels on the main tracks 101 in the trailing-point direction, while the left point of the switch is connected, the train wheels will force the switch points 104 to switch to the right to allow the train to continue through on the main tracks. Such trailing of an open switch is referred to as a “run-through.” A similar run-through could occur from the secondary tracks 102 when the switch is configured to allow train movements along the main tracks 101 , as shown in FIG. 1B .
After a railroad switch has been run through, it could be in one of a number of conditions. Assuming the switch is in the condition as shown in FIG. 1A before the run-through, FIGS. 2A-2B show potential conditions of the switch after the run-through. For example, the switch may return to its previous position as set before the run-through, which is shown in FIG. 2A . For another example, the switch may be damaged by the run-through and rest in an “in-between” position that connects neither the main tracks nor the secondary tracks, as is shown in FIG. 2B . Even if the switch remains connected in the run-through position (in this case, switched to the right side like in FIG. 1B ), the points are usually not tightly closed or locked in that position.
These post-run-through switch conditions may be problematic if a train somehow moves in reverse through the switch. For example, if the switch is damaged and remains in an “in-between” position as shown in FIG. 2B (or otherwise not securely closed or locked in the run-through position), the train wheels moving in reverse (i.e., in facing-point direction) will not be properly guided by the switch, which could cause derailment of the train. Even if the switch has returned to its pre-run-through position as shown in FIG. 2A , the reversing train could travel too fast for the switched curve to the secondary tracks, again potentially causing derailment.
In view of the foregoing, it may be understood that there are significant problems and shortcomings associated with current railroad switches.
SUMMARY OF THE INVENTION
Embodiments of innovative designs and use of switch rods are disclosed. In one particular embodiment, a method of preventing derailment of a train traveling through a previously run-through railroad switch may include installing a railroad switch rod assembly to couple a switch point of a railroad switch with a railroad switch stand. The method may also include configuring a locking mechanism in the railroad switch rod assembly such that, upon a railway vehicle trailing the railroad switch in a first direction, the locking mechanism maintains the railroad switch in a condition that accommodates safe movement of the railway vehicle through the railroad switch in a second direction opposite to the first direction.
In another embodiment, a detent assembly may be provided in the locking mechanism to restrict movement of a switch rod of the railroad switch rod assembly. In an alternative embodiment, at least one shear pin may be provided in the locking mechanism, the at least one shear pin configuring at least one spring to initially maintain the railroad switch in a first operating state and, when the at least one shearing pin breaks due to the run-through by the railway vehicle, to maintain the railroad switch in a second operating state.
In another particular embodiment, a railroad switch rod assembly may include a switch rod housing having a first end adapted to couple with a railroad switch stand, the switch rod housing further having a second end adapted to slidably receive a connecting rod into the switch rod housing. The railroad switch rod assembly may also include a detent assembly coupled to the switch rod housing, the detent assembly comprising a detent pin. The railroad switch rod assembly may further include the connecting rod, one end of the connecting rod being adapted to couple with a switch point of a railroad switch, the connecting rod having (a) a first notch to receive a tip of the detent pin in a first operating state of the railroad switch to maintain a first relative position of the connecting rod in the switch rod housing and (b) a second notch to receive the tip of the detent pin in a second operating state of the railroad switch to maintain a second relative position of the connecting rod in the switch rod housing.
In yet another embodiment, a railroad switch system may be made or modified to include any of the above-mentioned embodiments of the railroad switch rod assembly.
The present invention will now be described in more detail with reference to exemplary embodiments thereof as shown in the accompanying drawings. While the present invention is described below with reference to exemplary embodiments, it should be understood that the present invention is not limited thereto. Those of ordinary skill in the art having access to the teachings herein will recognize additional implementations, modifications, and embodiments, as well as other fields of use, which are within the scope of the present invention as described herein, and with respect to which the present invention may be of significant utility.
BRIEF DESCRIPTION OF THE DRAWINGS
In order to facilitate a fuller understanding of the present invention, reference is now made to the accompanying drawings, in which like elements are referenced with like numerals. These drawings should not be construed as limiting the present invention, but are intended to be exemplary only.
FIGS. 1A-1B show a typical railroad switch known in the art.
FIGS. 2A-2B show potential conditions of a railroad switch after a run-through has occurred.
FIG. 3 shows a diagram illustrating a desired state of a railroad switch after a run-through in accordance with an embodiment of the present invention.
FIG. 4 shows an exemplary switch rod assembly in accordance with an embodiment of the present invention.
FIG. 5 shows a switch rod housing and a spring housing of an exemplary switch rod assembly in accordance with an embodiment of the present invention.
FIG. 6 shows a connecting rod of an exemplary switch rod assembly in accordance with an embodiment of the present invention.
FIG. 7 shows a cross-sectional view of an exemplary spring detent assembly and its coupling to the rest of a switch rod assembly in accordance with an embodiment of the present invention.
FIG. 8 shows an exemplary spring detent pin in accordance with an embodiment of the present invention.
FIGS. 9A-9B show side views of an exemplary detent pin and connecting rod in accordance with an embodiment of the present invention.
FIGS. 10A and 10B show top and side views respectively of an exemplary switch rod assembly and its installation with a test stand in accordance with an embodiment of the present invention.
FIGS. 11A-11D show different operating states of an exemplary switch rod assembly in accordance with an embodiment of the present invention.
FIGS. 12 and 13 show the design and operation of another exemplary switch rod assembly in accordance with an alternative embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention provide for innovative designs and use of switch rods to prevent derailment of a train that traverses through a previously trailed railroad switch. In light of uncertain, and sometimes dangerous, conditions of the railroad switch after it has been run through by a trailing train, the inventor finds it desirable to have a switch that securely maintains or locks the switch points in the position forced by the run-through, rather than reverting to the position set before the run-through (or to any other position). A mechanism is therefore provided in the switch rod to accommodate a run-through and thereafter automatically cause the switch to remain in the same condition forced by the run-through. As a result of the design and use of the inventive switch rod assembly, the non-ideal conditions of the post-run-through railroad switch can be avoided, thereby eliminating or reducing the risk of derailment when a train attempts to traverse through a previously trailed railroad switch.
Other features and advantages of the present invention may be appreciated from the following illustration and description.
Referring to FIG. 3 , there is shown a diagram illustrating a desired state of a railroad switch after a run-through in accordance with an embodiment of the present invention. Continuing with the example shown in FIG. 2A , it is assumed that a train has run through a railroad switch along main tracks 101 in the trailing-point direction as shown. The railroad switch according to the present invention will be so designed and/or configured to cause the switch points to remain locked in the run-through direction such that no derailment would occur if the same train backs up or another train comes in the opposite (facing-point) direction through the switch.
A number of methods may be effective in causing the switch points to be locked in place after a run-through. According to embodiments of the present invention, it may be desirable to provide a locking mechanism in the switch rod that couples the switch points to the switch stand. Preferably, only the switch rod needs to be replaced or modified without making any change to the rest of the railroad switch components.
FIG. 4 shows an exemplary switch rod assembly in accordance with an embodiment of the present invention. The switch rod assembly 400 may comprise a switch rod housing 402 , a detent assembly 404 , and a connecting rod 406 . Details of these main components are shown in more detail in FIGS. 5-8 .
As shown in FIGS. 4 and 5 , the switch rod housing 402 may be primarily a cylindrically shaped component with a hollow cavity to receive the connecting rod 406 . The connecting rod 406 may be coupled to the switch rod housing 402 via a seal plate 407 attached to a first flange 511 at one end of the switch rod housing 402 . The detent assembly 404 may have a cylindrically shaped housing 504 that is coupled to the switch rod housing 402 via a cubic joint 508 . A top plate 405 , attached to a second flange 513 , may serve to secure the detent assembly 404 in its housing 504 .
The switch rod assembly 400 may be designed to replace an existing switch rod for a railroad switch assembly without requiring modifications to the rest of the railroad switch assembly or its switch stand. Accordingly, one end of the switch rod housing 402 is adapted, for example, in the shape of a fork 403 with screw or bolt holes, to couple with part of a switch assembly (not shown here); the other end ( 409 ) of the connecting rod 406 is adapted to couple with a switch stand of a railroad switch (not shown here). FIG. 10A shows a top view, and FIG. 10B shows a side view, of an exemplary switch rod assembly 1002 and its installation with a test switch stand 1006 in accordance with an embodiment of the present invention. As shown, the right end of the switch rod assembly 1002 is coupled to a railroad switch assembly 1004 while the left end of the switch rod assembly 1002 is coupled to the switch stand 1006 .
FIG. 6 shows a connecting rod of an exemplary switch rod assembly in accordance with an embodiment of the present invention. The connecting rod 406 may be a rigid, elongated and cylindrically shaped member. As is also well known in the art, the general dimensions of the connecting rod 406 may be so configured as to fit snuggly within and be able to slide along a corresponding switch rod housing (e.g., 402 ). One end ( 409 ) of the connecting rod 406 may be adapted to couple with a railroad switch assembly, for example, to move its switch point. Towards the other end (i.e., the end that is inserted into the switch rod housing), two or more notches may be formed on the connecting rod 406 . A first notch, 601 , may have a first profile and be located at a first position on the connecting rod 406 . At least one second notch, 602 or 603 , may have a second profile and be located at a second position on the connecting rod 406 . The profiles and relative positions of these notches are configured to work with a detent assembly, as will be described in more detail below. Between the first notch 601 and the at least one second notch 602 or 603 , the connecting rod 406 may be contoured to provide a channel to guide the relative movement of a detent pin, as will also be described in more detail below.
FIG. 7 shows a cross-sectional view of an exemplary spring detent assembly and its coupling to the rest of a switch rod assembly in accordance with an embodiment of the present invention. The spring detent assembly 700 may include a detent pin 800 , a bolt 704 , and a spring 702 , which are enclosed in a detent housing 504 . The detent housing 504 may be attached to the switch rod housing 402 via the cubic joint 508 such that the center axis of the two housings are preferably perpendicular to each other. An opening in a sidewall of the switch rod housing 402 may allow at least a portion of the tip of the detent pin 800 to pass through. The spring 702 exerts a downward tension on the detent pin 800 to cause its tip to protrude through the sidewall opening of the switch rod housing 402 .
Inside the switch rod housing 402 is slidably positioned the connecting rod 406 . The notches 601 - 603 on the connecting rod 406 may be on the same side as the sidewall opening. As shown in FIG. 7 , the first notch 601 is position at the sidewall opening now. The spring-tensioned detent pin 800 protrudes through the sidewall opening and has its tip engaged with the first notch 601 . As shown in FIG. 8 , the size and contour of the tip of the detent pin 800 may be so defined as to fit within the first notch 601 and press against its sidewalls to stop relative movement of the connecting rod 406 in the switch rod housing 402 . The contours of the tip of the detent pin 800 and sidewalls of the first notch 601 may be further configured as to allow a significant force exerted along the connecting rod 406 to disengage the detent pin 800 from the first notch 601 and to cause the detent pin 800 to slide relative to the connecting rod 406 . One example of such a significant longitudinal force may be the one caused by a train trailing through an open railroad switch. That is, the run-through may “kick” the connecting rod 406 loose from the detent pin 800 and cause it to move relative to the connecting rod towards the second notch 603 . It should be noted that the specific size and contour shown in FIG. 8 are exemplary and do not represent the only design option contemplated for the present invention.
According to an embodiment of the present invention, the second notch 603 may be located a distance D away from the first notch 601 wherein the distance D is approximately the same as the travel distance of the switch point of the railroad switch when it is toggled from one state to the other (e.g., from “fully open” to “fully closed”). Accordingly, when a run-through train forces the railroad switch into a different state, for example, by jerking the connecting rod 406 to the left, the detent pin 800 will be knocked out of the first notch 601 and finally land in the second notch 603 . As shown in FIG. 7 , the sidewall of the second notch 603 on the right hand side is relatively steep and may fully stop the connecting rod 406 from traveling any further to the left. By engaging the second notch 603 with the detent pin 800 , the connecting rod 406 can securely maintain the railroad switch in the same run-through position.
This operation is illustrated more clearly in FIGS. 9A-9B . FIG. 9A shows a side view of the exemplary detent pin 800 and connecting rod 406 when the railroad switch is in a first operating state. At this moment, the detent pin 800 engages with the first notch 601 to hold the switch in a normal condition. The first notch 601 may mark the reset (or normal operational) position of the detent pin 800 . The force applied by the train wheels during the run-through is sufficient to knock the tip of the detent pin 800 out of the first notch 601 and therefore causes the connecting rod 406 to slide to the left hand side until the detent pin 800 is stopped by the second notch 603 . FIG. 9B shows a side view of the exemplary detent pin 800 and connecting rod 406 when the railroad switch is locked in this second operating state after the run-through. The notch 603 may mark the right-lock position of the detent pin 800 . While, in this example, the run-through train forces the connecting rod 406 to move to the left, the same principle of operation applies when the connecting rod 406 is forced to the right hand side by a run-through train. In that case, the notch 602 located to the left side of the first notch 601 may accommodate and stop the detent pin 800 . The notch 602 may mark the left-lock position of the detent pin 800 .
FIGS. 11A-11D show different operating states of an exemplary switch rod assembly in accordance with an embodiment of the present invention. In these drawings, the setup illustrated in FIGS. 10A-10B is presented in cross-sectional views to show how the switch rod assembly 1002 is used and operates in connection with the test switch stand 1006 and the switch assembly 1004 .
FIG. 11A shows the switch rod assembly 1002 in its normal operational state when the detent pin is engaged in the reset position. The switch rod assembly 1002 now may function like a conventional switch rod. Routine toggling of the switch assembly 1004 by operating the switch stand 1006 will not affect the position of the detent pin. Thus, the entire length of the switch rod assembly 1002 remains the same during normal operations.
FIG. 11B shows the switch rod assembly 1002 in what is referred to as a “detent short” state when the detent pin is dislodged from the reset position and rests in the left-lock position. This may be due to a run-through of the switch assembly 1004 which forces the connecting rod to move to the right relative to the switch rod housing. As shown in FIG. 11B (and in FIG. 11D ), the maximum travel that the switch point can move is approximately five inches according to this embodiment.
FIG. 11C shows the switch rod assembly 1002 after it is returned to the operational state. The notch profile at the left-lock position ( FIG. 11B ) may allow connecting rod to be pulled to the left, thereby causing the detent pin to be re-engaged in the reset position.
FIG. 11D shows the switch rod assembly 1002 in what is referred to as a “detent long” state when the detent pin is dislodged from the reset position and rests in the right lock position. This may be due to a run-through of the switch assembly 1004 which forces the connecting rod to move to the left relative to the switch rod housing.
FIGS. 12 and 13 show the design and operation of another exemplary switch rod assembly in accordance with an alternative embodiment of the present invention. As shown in FIG. 12 , this alternative design of switch rod assembly may include a main body tube 1 that accommodates an extension rod end 2 on the switch stand side and a compression rod end 5 on the switch point side. Spring(s) 10 may be used to configure the switch rod in a predetermined state while shear pin(s) 8 may maintain the switch rod in that (“loaded”) state. When a run-through occurs, the switch rod will experience a significant longitudinal force which causes the shear pin(s) 8 to be broken and thereby release the compressed/extended spring(s) 10 . As a result, the spring(s) 10 may cause the switch rod to stay in the run-through direction even after the train has completely passed the switch location.
For example, in the normal state (“loaded view”) shown in FIG. 13 , the spring 10 on the extension rod end may by kept fully compressed (due to the corresponding shear pin 8 ), whereas the spring 10 on the compression rod end may by kept fully extended (also due to the corresponding shear pin 8 ). If the run-through train exerts a force that moves the switch point towards the switch stand (that is, compressing the switch rod overall), then at least the shear pin 8 on the compression rod end would break and cause the corresponding spring 10 to compress to its natural length, thereby causing the switch rod to stay in the broken state (“tripped view”) shown in FIG. 13 .
It should be noted that the above-described switch rod assembly need not be one that is constructed complete from scratch. Where applicable, some existing switch rods could be modified (“retrofitted”) based on the operating principles described herein.
While the foregoing description includes many details and specificities, it is to be understood that these have been included for purposes of explanation only, and are not to be interpreted as limitations of the present invention. It will be apparent to those skilled in the art that other modifications to the embodiments described above can be made without departing from the spirit and scope of the invention. Accordingly, such modifications are considered within the scope of the invention as intended to be encompassed by the following claims and their legal equivalents. | Embodiments of innovative designs and use of switch rods are disclosed. In one particular embodiment, a method of preventing derailment of a train traveling through a previously run-through railroad switch may include installing a railroad switch rod assembly to couple a switch point of a railroad switch with a railroad switch stand. The method may also include configuring a locking mechanism in the railroad switch rod assembly such that, upon a railway vehicle trailing the railroad switch in a first direction, the locking mechanism maintains the railroad switch in a condition that accommodates safe movement of the railway vehicle through the railroad switch in a second direction opposite to the first direction. | 1 |
RELATED APPLICATIONS
[0001] This application claims priority to U.S. Provisional Patent App. No. 60/803,222, filed on May 25, 2006, and entitled CUSTOMIZABLE COMPRESSION ORTHOSIS.
BACKGROUND
[0002] 1. Field of the Invention
[0003] This invention relates to orthopedic devices, and more particularly to an orthopedic compression brace to apply a hydrostatic compression force to an extremity of a user.
[0004] 2. Background
[0005] Functional fracture bracing is premised on the engineering principle of hydrostatic compression. Specifically, compressing the soft tissue around the bone produces increased intra-vascular hydrostatic pressure to stabilize the fracture and promote healing. The increased hydrostatic pressure created by the brace shifts the load that would be borne in the bone to the surrounding soft tissue, such that the soft tissue has a greater load-bearing effect than the brace itself. A rigid exterior frame may also be implemented to further stabilize the injury.
[0006] Fracture orthoses are advantageous over traditional rigid casting in many ways. Particularly, fracture orthoses are easily applied by a skilled physician or other professional. The speed of application can be a great asset in the trauma setting, as it enables the physician or other professional to manage multiple patients and perform any necessary adjustments quickly and easily. Fracture orthoses may also be easily adjusted to accommodate changes in the volume of the fractured extremity over time. In this manner, fracture orthoses may promote healing by maintaining hydrostatic pressure to stabilize the fractured bone as the volume of the affected limb decreases due to atrophy, or increases due to swelling. Fracture orthoses are also readily removable to enable effective hygiene management, and are generally more economic than traditional casts.
[0007] Many known fracture orthoses, however, are disadvantageous to patients that would benefit from light to moderate activity, such as stress fracture patients. Indeed, such fracture orthoses are generally too cumbersome and rigid to permit the movement required for such activity. Accordingly, recent developments in stress fracture treatment include stirrup-style pneumatic ankle control braces. Even these braces, however, present certain drawbacks.
[0008] Specifically, some stress fracture orthoses exert medial-lateral compression force to effectuate increased hydrostatic pressure, and are thus less effective in stabilizing a fracture than orthoses that provide circumferential compression force. Known stress fracture orthoses are also generally bulky and may be awkward to wear. For example, as previously mentioned, some lower leg orthoses require a stirrup underneath the foot that may create discomfort.
[0009] Also, known stress fracture orthoses, as well as fracture orthoses generally, are size-specific. This feature necessitates manufacture and storage of substantial quantities of orthoses in a wide range of sizes—some of which may never be used. Similarly, known orthoses are also generally specific to the right and left sides of a user's body, further contributing to an oversupply of orthoses and, inevitably, waste.
[0010] Accordingly, what is needed is a highly effective orthosis that exerts circumferential compressive force to effectuate increased hydrostatic pressure to stabilize a fracture. Further what is needed is an orthosis that is comfortable to wear and permits light to moderate activity. Also what is needed is an orthosis that is compact to store. Finally what is needed is a customizable orthosis that may be sized to a particular user, implemented on either a right or left extremity, and that substantially conforms to the user's body.
[0011] Such an orthosis is disclosed and claimed herein.
SUMMARY
[0012] The present invention has been developed in response to the present state of the art, and in particular, in response to the problems and needs in the art that have not yet been met for applying a hydrostatic compression force to an extremity of a user. Accordingly, the present invention has been developed to provide an apparatus, system and method for applying a compression force to an extremity of a user that overcomes many or all of the above-discussed shortcomings in the art.
[0013] A highly adaptable compression apparatus to apply a compression force to an extremity of a user in accordance with the present invention may include a compression overlay having a cinching mechanism coupled thereto. The compression overlay may selectively adhere to a compression sheath substantially surrounding an extremity of a user. The cinching mechanism may be tightened to contract the compression overlay, thereby tightening the compression sheath around the extremity. In this manner, the present invention may increase a hydrostatic compression force imparted to the extremity.
[0014] In some embodiments, the compression overlay includes more than one elongated mounting panel to mount the compression overlay to the compression sheath. A distance between the mounting panels may be adjusted to accommodate various users. In one embodiment, the mounting panels include hook and loop-type fastening elements to mount the compression overlay to the compression sheath. Further, one or more substantially rigid stays may be longitudinally integrated into the compression overlay to increase stability of the extremity.
[0015] In certain embodiments, the cinching mechanism of the present invention includes a cam-over device, such as straps or laces. In one embodiment, the cam-over device includes a plurality of straps. Each strap includes a primary looped portion fixed to the compression overlay, and a secondary portion slidably connected to the primary looped portion. The primary looped portion may be fixed to one mounting panel of the compression overlay and slidably connected to another mounting panel. In some embodiments, the secondary portion removably attaches the secondary portion to the compression sheath.
[0016] A system of the present invention is also presented to apply a compression force to an extremity of a user. The system may include a unitary compression sheath to substantially surround an extremity of a user. The unitary compression sheath may include a resilient portion to apply a hydrostatic compression force to the extremity, and an elastic portion to facilitate application and removal of the compression sheath. The system may further include a removable compression overlay to selectively adhere to the compression sheath. A cinching mechanism coupled to the overlay may contract the compression overlay upon tightening, thereby tightening the compression sheath around the extremity and increasing a hydrostatic compression force imparted thereto.
[0017] In some embodiments, the compression sheath may include longitudinal seams connecting the resilient portion to the elastic portion. These seams may facilitate positioning of the compression sheath with respect to the extremity. Longitudinal folds may extend from the longitudinal seams and be adapted to reduce pressure and irritation over bony prominences of the extremity.
[0018] A method to apply a compression force to an extremity of a user may include positioning a compression sheath around an extremity of a user and applying a removable compression overlay to the compression sheath. A cinching mechanism coupled to the compression overlay may be tightened to contract the compression overlay, thereby tightening the compression sheath around the extremity. The cinching mechanism may then be secured to increase a hydrostatic compression force imparted to the extremity. Further, in some embodiments, substantially rigid stays integrated into the compression overlay may be selectively positioned to increase stability of the extremity.
[0019] In one embodiment, applying the removable compression overlay may include mounting a first mounting panel of the overlay to the compression overlay. A second mounting panel of the overlay may be adjusted relative to the first mounting panel as needed to accommodate a particular extremity. The second mounting panel may then be mounted to the compression sheath.
[0020] These and other features and advantages of the present invention will be set forth or will become more fully apparent in the description that follows. The features and advantages may be realized and obtained by means of the instruments and combinations particularly pointed out in the appended claims. Furthermore, the features and advantages of the invention may be learned by the practice of the invention or will be obvious from the description, as set forth hereinafter.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] In order that the manner in which the above-recited and other advantages and features of the invention are obtained, a more particular description of the invention briefly described above will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings. Understanding that these drawings depict only typical embodiments of the invention and are not therefore to be considered limiting of its scope, the invention will be described and explained with additional specificity and detail through the use of the accompanying drawings in which:
[0022] FIG. 1 is a front view of one embodiment of an adaptable compression orthosis in accordance with the present invention;
[0023] FIG. 2 is a perspective view of one embodiment of an adaptable compression orthosis applied to a lower leg of a user in accordance with the present invention;
[0024] FIG. 3 is a perspective view of an alternative embodiment of an adaptable compression orthosis in accordance with the present invention;
[0025] FIG. 4 is a front view of one embodiment of a compression sheath that may be used in conjunction with an adapatable compression orthosis in accordance with the present invention;
[0026] FIG. 5 is a perspective view of the compression sheath of FIG. 4 fitted to a lower leg of a user; and
[0027] FIG. 6 is a flow chart detailing steps for applying a compression force to an extremity of a user in accordance with embodiments of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0028] The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. All changes that come within the meaning and range of equivalency of the claims are to be embraced within their scope.
[0029] The presently preferred embodiments of the invention will be best understood by reference to the drawings wherein like parts are designated by like numerals throughout.
[0030] As used in this specification, the term “orthosis” refers to an externally applied device used to modify the structural and/or functional characteristics of a limb or other extremity. The term “user” refers to any human or animal utilizing an orthosis to stabilize an extremity or other portion of the body as described herein.
[0031] Referring now to FIG. 1 , an adaptable compression orthosis 100 in accordance with the present invention may comprise a compression overlay 102 to selectively adhere to a compression sheath (not shown). The compression overlay 102 may be unitary or modular in design and may include one or more mounting panels 104 to mount the compression overlay 102 to the compression sheath. In one embodiment, for example, the mounting panels 104 include a hook and loop fastener, such as Velcro®, to mount the compression overlay 102 to the compression sheath.
[0032] A distance 106 between the mounting panels 104 may be adjusted as needed to fit a particular user. For example, the distance 106 may be shortened to accommodate an extremity having a larger circumference, and lengthened to accommodate an extremity having a smaller circumference. The distance 106 between the mounting panels 104 may also be adjusted along a length of the compression overlay 102 to accommodate circumferential variances along an extremity. For example, in a lower leg application, the distance 106 between mounting panels 104 may be shortened at the widest part of the calf and lengthened towards the ankle. This adjustability may also enable the compression overlay 102 of the present invention to be used in connection with various compression sheaths having varying topographies and contours.
[0033] The compression overlay 102 may further include a cinching mechanism 108 attached to the mounting panels 104 . The cinching mechanism 108 may include a cam-over device such as straps, laces, or any other such device known to those in the art. In operation, the cinching mechanism 108 may contract the compression overlay 102 upon tightening, thereby tightening the compression sheath around an extremity of a user. As a result, the hydrostatic compression force imparted to the extremity may be increased.
[0034] In one embodiment, the cinching mechanism 108 includes straps having a primary looped portion 112 fixed to the compression overlay 102 , and a secondary portion 114 slidably connected to the primary looped portion 112 . Alternatively, each strap may include a unitary or other modular design. The straps may include any natural or synthetic material known to those in the art. The primary looped portion 112 may be fixed to the compression overlay 102 by a fastening device 116 such as a ring, a clasp, a seam, a snap, a rivet, or the like. The secondary portion 114 may be slidably connected to the primary looped portion 112 via a connecting device 118 , such as a slidable ring.
[0035] In one embodiment, the primary looped portion 112 is attached to multiple mounting panels 104 a, 104 b of the compression overlay 102 . The primary looped portion 112 may be fixedly connected to one mounting panel 104 a with rivets 116 a , 116 b , and slidably connected to another mounting panel 104 b with rings 116 c , 116 d to facilitate tightening the cam-over device 108 to contract the compression overlay 102 . In one embodiment, the fastening devices 116 c , 116 d used to attach the primary looped portion 112 to the second mounting panel 114 b are flexibly attached to the second mounting panel 114 b to accommodate minor circumferential variation due to muscle flexion and the like.
[0036] The secondary portion 114 may include a removable fastening device (not shown) to secure the cam-over device 108 relative to the compression sheath, thereby maintaining the hydrostatic compression force imparted to the extremity. In one embodiment, for example, the secondary portion 114 may include a hook and loop fastening device, such as Velcro®, to secure the cam-over device 108 relative to the compression sheath. Alternatively, the secondary portion 114 may include a buckle, a snap, a hook, a loop, or any other device known to those in the art to secure the cam-over device 108 relative to the compression sheath.
[0037] Removably securing the cam-over device 108 relative to the compression sheath may enable customized application of the hydrostatic compression force to the extremity. Moreover, in some embodiments, variable distance between mounting panels 104 and adjustable securement of the cam-over device 108 with respect to the compression sheath combine to enable the present invention to provide a uniquely high level of adaptability.
[0038] In some embodiments, the compression overlay 102 may further include one or more substantially rigid stays 110 to further stabilize an affected extremity. The stays 110 may be longitudinally integrated into one or more of the mounting panels 104 to provide increased load-bearing support while avoiding interference with the adjustability and function of the present invention.
[0039] Referring now to FIG. 2 , the compression overlay 102 may be selectively attached to a compression sheath 200 and oriented to facilitate a user's ability to tighten the cam-over device 108 to apply a desired amount of hydrostatic compression force to an extremity. Moreover, in embodiments where the compression overlay 102 is entirely removable, an adaptable compression orthosis 100 in accordance with the present invention may not be side-specific, but may be implemented on either a right or left extremity.
[0040] In one embodiment, for example, the compression overlay 102 may be mounted to the compression sheath 200 and situated at the front of a user's lower leg. The user may mount one mounting panel 104 a substantially parallel to the tibia, or shin bone, and adjust a distance 106 between the mounting panel 104 a and a second mounting panel 104 b as needed to accommodate the lower leg. In some embodiments, the first mounting panel 104 a may be substantially permanently attached to the compression sheath 200 , while the second mounting panel 104 b may be removably attached thereto.
[0041] Upon securing the second mounting panel 104 b to the compression sheath 200 , the user may grasp the secondary portion 114 of the cam-over device 108 and pull it laterally towards the first mounting panel 104 a . In this manner, the secondary portion 114 of the cam-over device 108 may reverse over the primary looped portion 112 to cinch the mounting panels 104 a , 104 b together, thereby contracting the compression overlay 102 .
[0042] The secondary portion 114 of the cam-over device 108 may be removably secured to the compression sheath 200 by way of a hook and loop fastening device, such as Velcro®, or by any other means known to those in the art. Alternatively, the cinching mechanism 108 may be secured to the compression overlay 102 , and/or may be secured by an independent securing device. An independent securing device may include, for example, a knot, a bow, a clasp, a cinch, or any other suitable securing device known to those in the art. In this manner, the user may tighten and secure the compression sheath 200 around the lower leg to increase a hydrostatic compression force imparted thereto.
[0043] Referring now to FIG. 3 , an alternative embodiment of the cinching mechanism 108 may include laces 300 extending between opposing sides of the compression overlay 102 . In one embodiment, the laces 300 may extend between two mounting panels 104 a , 104 b . Specifically, each mounting panel 104 may include multiple eyelets 302 through which the laces 300 are threaded. Tightening the laces 300 may cinch the mounting panels 104 together, thereby contracting the compression overlay 102 to tighten the compression sheath 102 around an affected extremity. The laces 300 may be secured by a knot, a bow, a clasp, or any other means known to those in the art.
[0044] In some embodiments, as mentioned above, the laces 300 or other cam-over device 108 may cooperate with multiple mounting panels 104 to facilitate a customized application of hydrostatic compression force to an extremity. Indeed, while a distance 106 between mounting panels 104 may be adjustable, a user may be limited in his ability to manually increase this distance 106 to tighten the compression sheath 200 around the extremity. Accordingly, the laces 300 , straps, or other cam-over device 108 provide additional leverage to enable the user to easily and effectively tighten the compression sheath 200 around the extremity to increase the amount of hydrostatic compression force imparted thereto.
[0045] Referring now to FIGS. 4 and 5 , one embodiment of an adaptable compression orthosis 100 in accordance with the present invention includes a unitary compression sheath 200 to substantially surround an extremity of a user. The unitary compression sheath 200 may include a resilient portion 400 and an elastic portion 402 . The resilient portion 400 may apply a hydrostatic compression force to the extremity, while the elastic portion 402 may facilitate application and removal of the compression sheath 200 .
[0046] The resilient portion 400 may be adapted to substantially evenly distribute a circumferential compression force to stabilize an extremity. In some embodiments, the resilient portion 400 may include a flexible, substantially resilient material such as Neoprene®, foam rubber, plastic, nylon, or other suitable material known to those in the art. The resilient portion 400 may further include multiple layers to facilitate application and maintenance of a hydrostatic compression force.
[0047] In one embodiment, for example, the resilient portion 400 includes an outer layer 408 including a hook and loop fastening device such as Velcro®. This may enable the outer layer 408 to cooperate with the secondary portion 114 of the cinching mechanism 108 to secure the same. The resilient portion 400 may further include an inner layer 410 to mediate contact between the resilient portion 400 and the user's skin. The inner layer 410 may include a breathable material to improve circulation, reduce perspiration, and/or increase overall comfort. In some embodiments, the resilient portion 400 may further include one or more seams (not shown) and/or substantially collapsible sections to facilitate compact storage.
[0048] The elastic portion 402 of the compression sheath 200 may enable the compression sheath 200 to be applied over a foot, hand or other intermediary appendage of a user to substantially surround an affected extremity. In certain embodiments, for example, the elastic portion 402 may include Lycra®, Spandex®, nylon, or any other suitable elastic material known to those in the art.
[0049] In some embodiments, the elastic portion 402 may be attached to the resilient portion 400 via longitudinal seams 404 extending from a top 412 to a bottom 414 of the compression sheath 200 . In one embodiment, the seams 404 are integrated to create longitudinal folds 406 in the resilient portion 400 that extend beyond the edges 416 a , 416 b of the elastic portion 402 .
[0050] The longitudinal folds 406 may be positioned substantially laterally of a bone or bony prominence to reduce friction and pressure over the same. In this manner, the longitudinal folds 406 may bridge an applied hydrostatic compression force over sensitive areas to avoid skin irritation and pressure, while nevertheless imparting a substantially circumferential compression force to stabilize an affected extremity.
[0051] In some embodiments, the compression sheath 200 may include dimensions sufficient to accommodate a wide range of users. For example, in one embodiment, a compression sheath 200 for lower leg use in accordance with the invention includes small, medium narrow, medium wide, large narrow, and large wide sizes. These sizes are adapted to accommodate various users depending on lower leg length and calf circumference.
[0052] Referring now to FIG. 6 , a method 600 to apply a compression force to an extremity of a user in accordance with the present invention may include positioning 602 a compression sheath to substantially surround an extremity of a user and applying 604 a removable compression overlay to the compression sheath.
[0053] In some embodiments, the compression panel may include more than one mounting panel. A first mounting panel may be removably attached 606 to the compression sheath, or may be substantially permanently attached 606 thereto. A second mounting panel may be adjusted 608 relative to the first mounting panel as needed to accommodate an affected extremity of a particular user. The second mounting panel may then be removably attached 610 to the compression sheath.
[0054] A cinching mechanism attached to the compression overlay maybe tightened 612 to contract the compression overlay, thereby tightening the compression sheath around the extremity. The cinching mechanism may then be secured 614 to increase a hydrostatic compression force imparted to the extremity.
[0055] In some embodiments, the cinching mechanism may be secured to the compression sheath. Alternatively, the cinching mechanism may be secured to the compression overlay, and/or may be independently secured by a securing device. A securing device may include, for example, a knot, a bow, a clasp, a cinch, or any other suitable securing device known to those in the art.
[0056] In some embodiments, a method 600 in accordance with the present invention may further include positioning (not shown) a substantially rigid stay of the compression overlay to increase stability of the extremity. Specifically, one or more substantially rigid stays may be positioned to increase load-bearing support with respect to the affected extremity.
[0057] The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope. | A highly adaptable compression apparatus to apply a compression force to an extremity of a user. The apparatus includes a removable compression overlay to selectively adhere to a compression sheath surrounding an extremity of a user. A plurality of independently adjustable straps may be coupled to the compression overlay. Tightening the straps may contract the compression overlay to tighten the compression sheath around the extremity, thereby increasing a hydrostatic compression force imparted thereto | 0 |
FIELD OF THE INVENTION
This invention relates to a set of brackets for constructing a wooden gate.
BACKGROUND OF THE INVENTION
Corner gate brackets can be used to frame right angle joints between structural members of a gate at each of four corners. Such gate brackets are meant to provide a reliable guide for the positioning of the structural members to assist the do-it-yourself handy man. In addition, corner gate brackets are meant to minimize or eliminate the distortion of the gate structure over time.
Gate brackets are typically made of metal so as to resist bending and to ensure a rigid structure. Typically, a gate bracket comprises elongate flat metal members arranged in perpendicular relationship so as to guide the formation of a right angle between the pieces of structural lumber which are made to abut the elongate members. An example of such a system is disclosed in Boroviak, U.S. Pat. No. 6,896,244.
Parallel elongate flat metal members may be provided in a spaced relationship for bracketing structural lumber on two opposed sides and to provide a perpendicular arrangement of such elongate members. Such a system is disclosed in Cosgrove, U.S. Design Pat. No. D410,835. In Cosgrove, each pair of parallel elongate flat metal members form a U-shape and the two U-shaped pairs are welded together to form the overall bracket.
To provide structural rigidity for gate brackets, typically either a brace member is provided, as in Boroviak, or relatively thick metal members are provided, as in Cosgrove. In Boroviak, the diagonal brace member is welded to each of the perpendicular elongate metal members, which are in turn welded together at the intersection.
It is an object of the present invention to provide a structural gate bracket that serves to effectively frame a right angle between structural pieces, such as 2×4 pieces of lumber, while maintaining the structural relationship of the joint, over time, and at the same time not providing undue weight to the gate bracket, avoiding overly thick metal elements or excessive welding.
This and other objects of the invention will be better understood with reference to the detailed description of the invention which follows.
SUMMARY OF THE INVENTION
According to the invention, there is provided a web extending in a plane. A first pair of perpendicular elongate portions are provided normal to the plane of the web, preferably along two edges of the web. A second pair of perpendicular elongate portions are provided normal to the plane of the web in spaced parallel relationship to the first pair.
In another aspect of the invention, each pair of elongate portions comprises flanges of said web.
In a further aspect, an opening is provided in said web member between the first and second pairs of elongate portions.
In a further aspect, the opening extends between a first pair of parallel first and second members and between a second pair of parallel first and second members thereby defining a substantially L-shaped opening.
In another aspect, the invention comprises a web extending in perpendicular directions in a plane, said web including a first flange extending normal to said plane parallel to a first one of said directions, a second flange extending normal to said plane parallel to a second one of said directions in an end-to-end perpendicular, abutting relationship to said first flange. The web has an outer perimeter, an opening extending in generally perpendicular directions within said perimeter, a third flange normal to said plane along an edge of said opening and in spaced relationship to said first flange and a fourth flange normal to said plane along an edge of said opening and in spaced relationship to said second flange.
In another aspect, the invention comprises a method of forming a gate bracket comprising:
providing a web extending generally in perpendicular directions within a plane and having an opening within the perimeter thereof, said opening extending generally in said perpendicular directions; bending one edge of said web to provide a first flange normal to said plane; bending a second edge of said web to provide a second flange normal to said plane and abutting said first flange in a perpendicular relationship; bending a portion of said web that is adjacent to an edge of said opening to form a third flange normal to said plane; bending a portion of said web that is adjacent to an edge of said opening to provide a fourth flange normal to said plane and in perpendicular abutting relationship to said third flange.
The foregoing was intended as a broad summary only and of only some of the aspects of the invention. It was not intended to define the limits or requirements of the invention. Other aspects of the invention will be appreciated by reference to the detailed description of the invention and to the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be described by reference to the detailed description of the invention and to the drawings thereof in which:
FIG. 1 is a front perspective view of a first embodiment of the invention;
FIG. 2 is a rear perspective view of the first embodiment of the invention;
FIG. 3 is a plan view of the first embodiment;
FIG. 4 is a plan view of a web member, prior to bending, according to the method of the first embodiment;
FIG. 5 is a front perspective view of a web member of FIG. 4 after the bending of the first and second flanges according to the method of the first embodiment;
FIG. 6 is a rear perspective view of a second embodiment of the invention; and
FIG. 7 is a front perspective view of a third embodiment of the invention;
FIG. 8 is a front perspective view of a fourth embodiment of the invention; and
FIG. 9 is a plan view of the fourth embodiment of the invention, prior to bending.
DETAILED DESCRIPTION OF THE INVENTION
Throughout the following description specific details are set out to provide a more thorough understanding of the invention. However, the invention may be practiced without these particulars. In other instances, well known elements have not been shown or described in detail to avoid unnecessarily obscuring the present invention. Accordingly, the description and drawings are to be regarded in an illustrative, rather than a restrictive, sense.
Referring to FIGS. 1 , 2 and 3 the gate bracket of the first embodiment 10 includes a web 12 extending within a plane generally along two perpendicular directions 14 and 16 in a generally L-shaped configuration.
Web 12 has a generally L-shaped opening 18 that extends in perpendicular directions parallel to directions 14 and 16 . Opening 18 is spaced inwardly from the perimeter 20 of the web 12 .
A first flange 22 extends normal to the plane of the web 12 along a perimetral edge 24 of web 12 , parallel to direction 14 . A second flange 26 extends normal to the plane of the web 12 along a perimetral edge 28 of web 12 , parallel to direction 16 . First 22 and second 26 flanges are in abutting perpendicular relationship to one another.
A third flange 30 extends normal to the plane of the web 12 along an edge 32 of opening 18 . Third flange 30 extends parallel to first flange 22 and in spaced relationship therewith.
A fourth flange 34 extends normal to the plane of the web 12 along an edge 36 of opening 18 . Third 30 and fourth 34 flanges are in abutting perpendicular relationship to one another.
The spacing between first 22 and third 30 flanges is selected so as to correspond to the dimensions of structural pieces (such as lumber, plastic or metal), to be used in the gate system, as is the spacing between second 26 and fourth 34 flanges.
One end of each of the third and fourth flanges may optionally be further bent away from opening 18 as at 38 , 40 in order to provide additional structure rigidity to the flanges.
A hinge 42 may be provided on selected brackets according to whether the bracket will be used on the hinge side of the gate to be constructed.
One advantage of the first embodiment of the invention is that the entire structure, save for the attachment of a hinge, may be formed from a single flat sheet of materials, as will be described by reference to FIGS. 4 and 5 .
There is first provided a web 12 as shown in FIG. 4 that extends generally in two perpendicular directions 14 and 16 . Web 12 is cut at 17 , 19 , 21 and 23 , with cut 19 being parallel to direction 14 and cut 21 being parallel to direction 16 . Each cut 17 , 19 , 21 , 23 is spaced inwardly from the edges of web 12 . A gap 15 is provided at the juncture cut lines 19 and 21 .
An elongated rectangular portion 30 is bent from the plane of the web so as to be normal to it and an elongated rectangular portion 34 is bent from the plane of the web so as to be normal to it to form flanges 30 and 34 .
Short end portions 29 , 31 of flanges 30 , 34 may then be bent along lines 33 , 35 so as to be normal to flanges 30 , 34 to provide structural rigidity to flanges 30 , 34 .
An elongated rectangular portion 22 along edge 25 of web 12 is bent so as to form a flange 22 that is normal to the plane of the web 12 . An elongated rectangular portion 26 along edge 27 of web 12 is bent so as to form a flange 26 that is normal to the plane of the web 12 . Once bent, flanges 22 and 26 are in abutting perpendicular relationship and flanges 30 , 34 are in abutting perpendicular relationship, as seen in FIGS. 1 and 2 .
As shown in a second embodiment 60 illustrated in FIG. 6 , the shape of the web 12 may be altered in area 68 , for example to increase rigidity, and the hinge 42 may not be provided on selected brackets.
As shown in the third embodiment 70 shown in FIG. 7 , alternate embodiments of the invention do not require web 12 to extend into area 68 beyond flanges 30 and 40 . Optional piece 76 could be welded between flanges 30 and 40 to assist with the structural integrity of the bracket.
A fourth embodiment 80 is shown in FIG. 8 in which a straight edge 86 can brace the portion between perpendicular structural members on a corner. Flanges 82 and 84 can be attached to the outside edges of structural members while flanges 88 and 90 can be attached to the inside edges. Flange 82 together with flange 88 and flange 84 together with flange 90 can firmly hold the structural members (such as 2×4 lumber pieces) of the corner of a gate in place. When folded in position, flanges 88 and 90 leave openings 92 and 94 in embodiment 80 . The edge along 86 can be reinforced by folding the edge over itself, as shown in FIGS. 8 and 9 . Further, a hole 96 may be provided, for example to reduce the overall material used and the weight of the embodiment. For versions of embodiment 80 used on the side of the gate to which a hinge should be attached, a hinge may be attached to one of flanges 82 and 84 , and preferably to flange 84 . As shown in FIG. 9 with reference to planar layout 98 , embodiment 80 can be made from a flat piece of unitary material, such as sheet metal.
In a method of assembly of a gate or door, four brackets as described above, may be used in the construction of a gate. Two brackets placed on adjacent corners may have hinges, whereas the two other brackets may not have hinges. Structural pieces, such as lumber, plastic or metal members may be used in the assembly of the gate. Typically four structural pieces of lumber (or equivalent) will be used to create a gate frame in a square or rectangular formation. Gate face structural members, such as 2×4 pieces of lumber, can then be secured to the gate frame to complete the gate. As understood in the art, the face structural members could be attached to one side of the gate frame, on both sides, or having face structural members in an alternating pattern with structural members secured to opposing sides of the gate frame.
Many other variations or additional features can be practiced in accordance with this invention. For example, a structural brace 66 could be added between flanges 30 and 34 . The structural brace would help maintain the structural integrity of the corner of the gate. The structural brace could be placed at any suitable angle, such as 45 degrees from each of flanges 30 and 34 .
Portions 64 of web 12 could be punched out, cut out, or otherwise removed from the structure without departing from the scope of the invention. Cutting out portions 64 of web 12 could be of any desired shape and location and would reduce the amount of material, such as metal, and reduce the weight of the gate bracket.
In certain embodiments, reinforcing lines 62 could be used to add structural integrity to the metal. Reinforcing lines 62 could be depressions formed on one side of the metal, with a corresponding protrusion on the opposite side of the metal. To maximize effectiveness of the reinforcing lines 62 , the lines may be linear. Reinforcing lines 62 could be added to web 12 or flanges 30 and 31 .
It will be appreciated by those skilled in the art that the first and second embodiments have been described above in some detail but that certain modifications may be practiced without departing from the principles of the invention. | A gate bracket is formed of a planar web in which two rectangular portions along two edges of the web are bent to define a first pair of perpendicular flanges, and two other rectangular portions are bent from an inner portion of the web to form a second pair of perpendicular flanges. The flanges of the first pair are spaced from the flanges of the second pair by a distance corresponding to the dimensions of the structural members used to construct the gate. The invention provides a rigid bracket of simpler and lighter construction than prior art brackets. | 4 |
TECHNICAL FIELD OF THE INVENTION
[0001] The present invention relates, in a general manner, to the technical field of tower cranes. More particularly, this invention relates to the mechanism for slewing the rotating part of a tower crane, and more precisely still to the device for placing the tower crane in weathervaning mode, which device is associated with the slewing mechanism and which, in the case of the present invention, is aimed at facilitating the weathervaning of the crane in a disturbed wind.
BRIEF DESCRIPTION OF RELATED ART
[0002] A tower crane is conventionally composed of two main parts, firstly a nonrotating vertical pylon, also designated as “mast”, and secondly a rotating upper part, that is to say capable of slewing about a vertical axis of rotation. The rotating upper part, mounted at the top of the mast, is itself composed of a jib, which extends on one side of the vertical axis of rotation of this rotating part, and of a counterjib which is equipped with a ballast and which extends on the other side of the vertical axis of rotation, thus on the opposite side to the jib. The rotating part is rotated about this vertical axis by means of a motor-driven assembly, designated here as slewing mechanism.
[0003] In order to mount the rotating part at the top of the mast of a tower crane, there is usually provided a slewing ring bearing which is interposed between the jib and the counterjib of the rotating part, said bearing being composed of two concentric rings, with one fixed ring connected to the top of the mast and with a movable ring secured to the rotating part, and balls or cylindrical rollers are mounted in a rolling manner between said rings.
[0004] In order to rotate the rotating part thus mounted, the slewing mechanism usually comprises at least one electric geared motor unit secured to this rotating part, the geared motor unit rotationally driving a pinion of vertical axis which is engaged with a toothed wheel cut into the fixed ring of the slewing ring bearing. Depending on the mechanical power that needs to be transmitted to set the rotating part in rotation, one, two or more geared reduction units may be mounted on the rotating part. The slewing ring bearing is designed to allow the rotating part to rotate with a minimum drive torque; nevertheless, a torque must be exerted between the parts in question of the crane that is sufficient to overcome the friction of the balls or cylindrical rollers inserted between the fixed ring and the movable ring of the slewing ring bearing.
[0005] The slewing geared motor unit usually has an internal brake controlled by an electromagnet. When the geared motor unit is at a standstill, the coil of the electromagnet is not supplied electrically, and a braking torque is exerted. By contrast, when the electromagnet is supplied electrically, no braking torque is exerted by this brake. If there are a plurality of slewing geared motor units, at least one of them is equipped with such a brake, which comes into play during the operating periods of the crane.
[0006] Outside these working periods, that is to say when it is “out of service”, a tower crane is usually placed in weathervaning mode, that is to say that the rotating part of the crane is allowed to slew freely according to the direction of the wind. The counterjib is thus placed against the wind while the jib is oriented in the direction of the wind, since the area of the jib that is exposed to the wind is greater than that of the counterjib. It may arise that the area of the jib exposed to the wind is increased by, for example, vertical plates being added within the jib. To allow the crane to be placed in weathervaning mode, the crane operator deactivates the brake of the slewing motor when he leaves his operating cab.
[0007] Such systems are described, for example, in patent documents FR 2135689 and EP1422188.
[0008] Nevertheless, when the tower crane is installed in a disturbed environment as far as the wind conditions are concerned, the speed and force of the wind which strikes the counterjib can be very different from the speed and force of the wind which simultaneously strikes the jib. The difference between the rotational torque applied to the jib and the rotational torque applied to the counterjib then becomes much greater than the frictional torque of the slewing ring bearing, with the result that the rotating part of the crane, instead of being placed in the direction of the wind, will start to rotate in a certain direction without stopping. Thus, the crane does not manage to weathervane correctly, and its rotating part is driven with an uncontrolled rotation. Under such conditions, there is a risk that the crane might topple over, particularly if a gust of wind strikes the rotating part when said part is oriented perpendicularly to the direction of the wind.
[0009] Such disturbed conditions may particularly arise if the crane is installed in an urban site in which neighboring tall buildings exert an influence, or in natural sites such as close to a cliff or in an enclosed valley, or else close to cooling towers of power stations, and other similar situations.
[0010] In order to prevent the rotating part of a tower crane from rotating uncontrollably when it is installed on such a site subject to disturbed winds, and hence to avoid the risk of the crane toppling over, a solution has already been proposed which involves interposing, in the slewing mechanism, an additional brake which, when the crane is placed in weathervaning mode, exerts a permanent braking torque that is sufficient to prevent uncontrolled rotation of the rotating part while leaving weathervaning possible. This solution has been described in French patent application 07.05817 of Aug. 10, 2007, published under number FR 2 919 853, and in corresponding European patent application 08356064.9 of Apr. 24, 2008, published under number EP 2025637, in the name of the Applicant.
[0011] According to these documents, the proposed solution consists, in the case of a slewing mechanism comprising at least two geared motor units, in providing a geared motor unit having a main brake used for the normal operation of the crane, and another geared motor unit which is equipped with the additional brake intended to brake the rotating part when the crane is out of service, in order to ensure correct weathervaning.
[0012] This solution has the disadvantage of being specific to one construction site and to one crane and, since it demands modifications to a crane resulting from mass production, it makes it necessary for the crane to be brought into compliance after work on a construction site has finished. Moreover, this solution is not suited to the case of a slewing mechanism having a single geared reduction unit, unless there is added to the output of the geared reduction unit an external additional brake which, for its part, requires a significant conversion of the crane.
BRIEF SUMMARY OF THE INVENTION
[0013] The present invention aims to eliminate these disadvantages, therefore to provide an alternative solution to the problem of the uncontrolled rotation of the rotating part of the crane in the event of disturbed wind, which solution does not require any modification to a mass-produced crane and which can be easily transposed from one construction site to another, and which, moreover, constitutes an appropriate solution for cranes in which the slewing mechanism has only one geared motor unit.
[0014] Accordingly, the subject of the present invention is a mechanism for slewing the rotating part of a tower crane, with a device for placing the tower crane in weathervaning mode, the mechanism comprising at least one slewing geared reduction unit with a motor and reduction gear, and with an internal main brake which is deactivated when the crane is placed out of service, and also additional braking means which can be activated when the crane is placed out of service in order to exert on the rotating part of the crane a braking torque which avoids uncontrolled rotation of said rotating part when placed in weathervaning mode, this slewing mechanism being essentially characterized in that the additional braking means are incorporated in the geared motor unit or in one of the geared motor units in the form of an internal auxiliary brake interposed between the motor and the reduction gear.
[0015] In a preferred embodiment of the invention, the internal auxiliary brake, interposed between the motor and the reduction gear, is a single disk brake controlled by an electromagnet, this brake being supplied electrically so as not to brake the rotation of the rotating part of the crane when the crane is in service, but exerting a braking torque by way of spring means when it is not supplied electrically, thereby avoiding uncontrolled rotation of the rotating part of the crane when it is placed in weathervaning mode.
[0016] Thus, the solution of the invention consists of the addition, within the single geared motor unit or within one of the geared motor units of the slewing mechanism, of an optionally demountable electromechanical assembly composed of a brake, of its electrical box and of its bundle of cables, the device being able to brake an internal shaft of the geared motor unit, and hence to brake the rotating part of the tower crane, while being operational when the crane is placed in weathervaning mode. Conversely, this auxiliary brake must not brake the rotation of the rotating part when the crane is in service, only the main brake coming into play during the operation of the crane. The choice of a single disk brake having electromagnetic control here constitutes a particularly advantageous solution in terms of structural simplicity, space requirement and control.
[0017] Advantageously, the auxiliary brake is designed to exert an adjustable braking torque. In particular, if the brake is a disk brake controlled by an electromagnet and urged in the direction of braking by spring means, these means preferably take the form of compression springs acting axially on an armature disk, the compression of the springs or of certain springs being adjustable by screwing an adjusting ring. Thus, the solution of the present invention can be easily transposed from one construction site to another construction site in which there is also a risk of uncontrolled rotation of the rotating part of the crane, since it allows a straightforward adjustment of the braking torque exerted on this rotating part when the crane is out of service. The device of the invention even allows a use on a construction site where there is no disturbed wind, or without demounting the auxiliary brake, if the braking torque of the auxiliary brake can be adjusted to a zero value, in other words if the springs can be relaxed to such a point that they no longer act on the brake disk.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] The invention will be better understood with the aid of the description which follows, with reference to the appended schematic drawing which, by way of example, represents an embodiment of this device for placing a tower crane in weathervaning mode;
[0019] FIG. 1 is a diagram illustrating, in a top plan view, the action of the wind on the rotating part of a tower crane;
[0020] FIG. 2 is a partial side view of the rotating part and in particular of the slewing mechanism of a tower crane, equipped with the device according to the invention;
[0021] FIG. 3 represents, highly schematically, the device of the invention and in particular the geared motor unit equipped with the auxiliary brake;
[0022] FIG. 4 is a detailed view, in section, of this brake in a particular embodiment.
DETAILED DESCRIPTION OF THE INVENTION
[0023] Referring to FIGS. 1 and 2 , the rotating part 2 of a tower crane is composed of a jib 3 and of a counterjib 4 , which are aligned on either side of a slewing ring bearing 5 of vertical axis which is mounted on the top 6 of the mast (not shown itself) of the crane. The slewing ring bearing 5 is itself composed of two rings, namely a fixed ring connected to the top 6 of the mast and a movable ring connected to the rotating part 2 , the fixed ring externally forming a toothed wheel 7 . A geared motor unit 8 , which is secured to the rotating part 2 , is coupled to a pinion 9 , of vertical axis A, which engages with the toothed wheel 7 —see also FIG. 3 .
[0024] In a known manner, as shown in FIG. 3 , the geared motor unit 8 comprises an electric motor 10 , a reduction gearset 11 and an internal main brake 12 , here placed above the motor 10 . Provided above the main brake 12 is a weathervaning device 13 , itself surmounted by an encoder 14 . The weathervaning device 13 makes it possible to mechanically lock the main brake 12 in a nonbraked position when the crane is out of service so that the rotating part 2 can be oriented in the direction of the wind. When the crane is in service, the main brake 12 is automatically actuated while the motor 10 is not supplied with power, and it thus constitutes a service brake.
[0025] According to the invention, an auxiliary brake 15 is interposed between the output of the electric motor 10 and the input of the reduction gear 11 , inside the geared motor unit 8 . The auxiliary brake 15 springs into action only when the crane is placed out of service, in order to exert a braking torque on the rotating part 2 and thus avoid uncontrolled weathervaning in the event of a disturbed wind. In practice, the crane operator, at the end of his working day, places the crane in weathervaning mode by deactivating the main brake 12 of the geared motor unit 8 and by then activating the auxiliary brake 15 so that it can exert its braking torque.
[0026] Referring once again to FIG. 1 , a wind having a certain speed and direction, indicated by the arrow V, exerts on the rotating part 2 of the crane in question two oppositely directed torques, namely:
a torque Cfl applied by the wind to the jib 3 , and a torque Ccf applied by the wind to the counterjib 4 .
[0029] In addition, a frictional torque Ccou must be taken into consideration at the slewing ring bearing 5 of the rotating part 2 .
[0030] The main brake 12 must accommodate the difference in torque between the jib 3 and the counterjib 4 , while taking account of the frictional torque, up to a maximum wind speed V1 defined by the relevant standards, for example a speed of 72 km/h. Thus, the braking torque Cfr 1 for such a wind speed V1 that has to be exerted by this brake 12 must satisfy the following relationship:
[0000]
Cfr
1
>Cfl
1
−Ccf
1
−Ccou
[0000] where Cfl 1 and Ccf 1 represent the torques applied by a wind speed V1 to the jib 3 and to the counterjib 4 , respectively.
[0031] The braking torque, designated Cfr 2 , exerted by the auxiliary brake 15 in order to avoid uncontrolled rotation of the rotating part 2 of the crane in a disturbed wind is given by the following formula:
[0000]
Cfr
2
=Cfl
2
−Ccf
2
−Ccou
[0000] where:
Cfl 2 represents the torque applied to the jib 3 by a wind having a certain speed V2 which is less than the maximum speed V1, Ccf 2 represents the torque applied to the counterjib 4 by the same wind of speed V2 which is less than the maximum speed V1, Ccou represents, as above, the frictional torque of the ring bearing 5 .
[0035] The wind speed V2 is, for example, equal to 55 km/h (whereas, in the case taken here for example, the speed V1 is equal to 72 km/h).
[0036] In order to obtain the braking torque Cfr 2 which complies with the above-indicated relationship, all that is required is to use an auxiliary brake 15 provided with one or more springs whose relaxation force gives the desired torque value.
[0037] FIG. 4 illustrates the structure of the internal auxiliary brake in more detail, and makes it possible to understand the operation thereof, in the case of a particular embodiment in which this brake 15 is a single disk brake having electromagnet control.
[0038] In FIG. 4 , the reference 16 designates a shaft which is internal to the geared motor unit 8 and which constitutes both the output shaft of the motor (not shown—situated on the right) and the input shaft of the reduction gear (not shown—situated on the left). The shaft 16 passes freely through a flange 17 and it carries a rotor 18 composed of a central hub 19 , which is keyed to this shaft 16 , and of an annular disk 20 provided at its periphery with linings 21 on both surfaces thereof.
[0039] On its side facing the motor, the auxiliary brake 15 includes, coaxially to the shaft 16 , an electromagnet 22 comprising a coil 23 and a fixed inductor body 24 , which is assembled by means of hollow screws 25 to the flange 17 . A nonrotating armature disk 26 is mounted between the inductor body 24 and the disk 20 , around the hub 19 , the hollow screws 25 passing freely through the armature disk 26 .
[0040] Springs 27 and 28 are housed in bores in the inductor body 24 . The springs 27 , which have an “outboard” arrangement, are helical compression springs housed in blind bores and pressed, by one end, against one surface of the armature disk 26 . The other springs 28 , which have an “inboard” arrangement, are helical compression springs housed in through-bores and pressed, by one end, against the same surface of the armature disk 26 as the previous springs 27 .
[0041] An adjusting ring 29 , situated on the motor side, has a threaded hub 30 screwed into the central opening in the inductor body 24 , and a collar 31 which, by way of small pistons 32 , presses against the ends (the ones facing away from the disk 26 ) of the springs 28 .
[0042] The hollow screws 25 make it possible to adjust the air gap E which, in the braked position, separates the armature disk 26 from the inductor body 24 so that the coil 23 can correctly attract this disk 26 and release the brake 15 . The adjusting ring 29 makes it possible to set the braking torque to the desired value. By screwing this adjusting ring 29 into the inductor body 24 , the length of the “inboard” springs 28 is reduced, the springs 28 being compressed more. Consequently, these springs 28 apply a greater force to the armature disk 26 , which itself transmits this force to the disk 20 of the rotor 18 , with the result that the braking torque is increased.
[0043] When the crane is placed in weathervaning mode, the coil 23 of the electromagnet 22 is not energized, with the result that the armature disk 26 is no longer magnetically attracted toward the inductor body 24 . The springs 27 and 28 axially push away the armature disk 26 in the direction of the disk 20 of the rotor 18 , thereby braking the shaft 16 . Any rotational movement of the rotating part 2 of the crane tends to be transmitted, via the toothed wheel 7 and the reduction gear 11 , to the shaft 16 , but the latter is braked by the auxiliary brake 15 . When the crane is in service, the electromagnet 22 of this brake 15 is activated and it attracts the armature disk 26 while compressing the springs 27 and 28 , thus releasing the disk 20 of the rotor 18 . The slewing torque produced by the motor 10 then “traverses” the brake 15 , via the shaft 16 , to be transmitted to the reduction gear 11 .
[0044] Adjusting the auxiliary brake 15 , which is carried out by screwing or unscrewing the adjusting ring 29 to a greater or lesser degree, makes it possible to cover a wide range of braking torques, for example between 4 N.m and 40 N.m. According to one advantageous possibility, the braking torque of the auxiliary brake 15 can be cancelled, thus making it possible to use the device on a construction site where there is no risk of disturbed wind. The braking torque can also be adjusted, in part, by modifying the number of springs acting on the armature disk 26 .
[0045] The scope of the invention, as defined in the appended claims, would not be departed from:
by replacing the internal auxiliary disk brake having electromagnetic control with a brake of some other type, likewise capable of exerting a braking torque on the rotating part placed in weathervaning mode; by applying the invention to a tower crane slewing mechanism having any number of geared motor units, in which case the auxiliary brake equips either only one of the geared motor units or a plurality of these geared motor units. | Each arm of the scissors comprises a handle with a rigid outer ring and an inner ring made of a flexible and elastically deformable material. The flexible inner ring includes a part resembling a length of tube and receiving one or more of a user's fingers, and a thin membrane-like part which connects the preceding part to the rigid outer ring of the handle. This configuration is both comfortable and firm. | 1 |
FIELD OF THE INVENTION
The invention is in the field of currency dispensers and relates more particularly to a currency dispenser especially adapted for use at installations involving a high volume of low dollar amount transactions.
BACKGROUND OF THE INVENTION
There are known in the prior art a number of devices for dispensing currency from a number of supplies corresponding respectively to different denominations of bills. One example of such a currency dispenser is shown and described in U.S. Pat. No. 4,660,882. Currency dispensers of the type shown in this patent are particularly adapted for use in relatively secure installations such as banks and the like, wherein each individual transaction involves a relatively large sum of money. At such an installation, moreover, the number of transactions per unit time is not particularly significant.
There are many locations at which a very large number of relatively low dollar amount transactions must be accomplished in a short period of time. Retail outlets such as fast food stores and convenience stores are examples of such locations. It will readily be appreciated that the speed and accuracy with which transactions can be carried out in such locations contributes to the overall volume of business and result in profit to the proprietor. Customer satisfaction is enhanced by any reduction in the period of time the customer must wait in line.
Recognizing the desirability of the use of an automatic currency dispenser in a location such as a fast food shop, consideration must also be given to other factors. The dispenser must be accurate and reliable. It must be secure. It should be simple and inexpensive for the result achieved thereby. It should be compact to permit its use on relatively crowded countertops. It is desirable that it have under counter capability both for security and space saving considerations. It should be compatible with coin dispensing mechanisms. It should be relatively easy to manufacture and to service.
SUMMARY OF THE INVENTION
We have invented a simplified currency dispenser which is especially adapted for use where a high volume of relatively low dollar amount transactions are being carried out.
Another object of our invention is to provide a simplified currency dispenser which is accurate and reliable.
A further object of our invention is to provide a simplified currency dispenser which is simple and compact.
Yet another object of our invention is to provide a currency dispenser which is inexpensive.
A still further object of our invention is to provide a simplified currency dispenser which is easy to service.
Other and further objects of our invention will appear from the following description.
BRIEF DESCRIPTION OF THE DRAWINGS
In the accompanying drawings to which reference is made in the instant specification and which are to be read in conjunction therewith and in which like reference numerals are used to indicate like parts in the various views:
FIG. 1 is a sectional view of our simplified currency dispenser.
FIG. 2 is a plan view of the drive and roller mechanism of our simplified currency dispenser with the elements shown in the same plane for purposes of clarity.
FIG. 3 is a fragmentary sectional view of our simplified currency dispenser.
FIG. 4 is a side elevation with the cover removed of our simplified currency dispenser.
FIG. 5 is a fragmentary sectional view of one of the dispensing units of our currency dispenser.
FIG. 6 is a side elevation of an alternate embodiment of our simplified currency dispenser, with parts removed.
FIG. 7 is a plan of the bill elevating mechanism shown in FIG. 6 with parts removed.
FIG. 8 is a plan view of the keyboard and display portion of our simplified coin dispenser.
FIG. 9 is a block diagram illustrating the relationship of the central processing unit of our simplified coin dispenser to the peripheral apparatus.
FIG. 10 is a schematic diagram illustrating the portion of the analog circuitry of our dispenser incorporating various sensing means.
FIG. 11 is a schematic view of another portion of the analog circuitry of our currency dispenser illustrating other sensors.
FIG. 12 is a fragmentary schematic view illustrating a pulse encoder which may be incorporated in our simplified currency dispenser.
FIG. 13 is a schematic view of the motor control circuitry of our simplified currency dispenser.
FIG. 14 is a diagrammatic view of a portion of the microprocessor board of our simplified currency dispenser.
FIG. 15 is a diagrammatic view of another portion of the microprocessor circuitry of our simplified currency dispenser.
FIG. 16 is a diagrammatic view of a further portion of the microprocessor board of our simplified currency dispenser.
FIG. 17 is a diagrammatic view of a still further portion of the microprocessor board of our simplified currency dispenser.
FIG. 18 is a diagrammatic view of a further portion of the microprocessor board of our simplified currency dispenser.
FIG. 19 is a schematic view of the display control circuitry of our simplified microprocessor.
FIGS. 20 through 29 make up a flow diagram of the control program of our simplified currency dispenser.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to FIGS. 1 to 5 of the drawings, our currency dispenser, indicated generally by the reference character 10, includes an outer casing having a front wall 12, a back wall 14, side walls 16 and a top wall 18. The top wall 18 includes a cover 20 pivotally mounted on a hinge 22 for movement between an open position at which the supply of bills to be dispensed can be replenished, and a closed position at which the interior of the casing is inaccessible. If desired, a lock may be incorporated in the apparatus to secure the cover in its closed position.
In order to facilitate the manufacture of our dispenser we assemble the apparatus in two parts; one of which is a lower frame section indicated generally by the reference character 24, comprising a base 26 and side walls 28 and 30 spaced inboard from the lateral edge of the base plate 26. An upper frame section indicated generally by the reference character 32 of our apparatus includes a back wall 34, and spaced side walls 36 and 38 which register with the side walls 28 and 30 of the lower section 24.
Our dispenser includes a first dispensing unit indicated generally by the reference character 40 which may, for example, be adapted to dispense a note of the lowest denomination, such for example as a one dollar bill. A second unit indicated generally by the reference character 42 may be arranged to dispense bills of the next to lowest denomination of currency, such for example as five dollar bills.
Since the units 40 and 42 are substantially identical, only the unit 42, for example, will be described in detail. In connection with this description, it is to be understood that for purposes of clarity, the locations of the shafts in FIG. 2 have been shown as being all in the same plane and accordingly spaced along the length of the upper frame section 32.
The unit 42 includes a feed roller shaft 44 rotatably supported in respective bearings 46 and 48 carried by the sides 36 and 38 of the upper frame unit 32. A pair of upper feed rolls 50 and 52 are supported in spaced relationship on the shaft 44 for rotation therewith. An upper idler accelerating roller 54 is carried by the shaft 44 between the two rollers 50 and 52.
We mount a lower accelerator roller shaft 56 in bearings 58 and 60 carried by the walls 36 and 38 of the upper section 42. Shaft 56 supports for rotation therewith a lower accelerating roller 62 at a location at which it cooperates with the upper accelerating roller 54. Shaft 56 also carries a gear 64 which meshes with a gear 66 carried by shaft 44 for rotation therewith. A pulley 68 is adapted to be driven in a manner to be described to rotate shaft 56.
Shaft 44 also carries a pulley 70 of reduced diameter which is adapted to drive a timing belt 72 which also engages a pulley 74 carried by a shaft 76 supported in respective bushings 78 and 80 carried by the sides 36 and 38. Shaft 76 supports a picker roller 82 which, in operation of the apparatus, is adapted to remove the lowermost sheet of a stack supported thereabove and to feed it to the rolls 52.
Respective one-way clutch bearings 83 and 85 mount pulleys 84 and 86 on shaft 4 at positions outboard of the feed rollers 52. Pulleys 84 and 86 receive respective belts 88 and 90. These belts 88 and 90 extend around respective pulleys 92 and 94 rotatably supported on a fixed shaft 96 extending between the sides 36 and 38. Another fixed shaft 98 extending between the sides 36 and 38 rotatably carries a pair of rollers 100 and 102 at locations corresponding to the pulleys 92 and 94 so that the rollers 100 and 102 cooperate with the belts 88 and 90 to advance bills in a manner to be described.
The fives dispenser 42 includes a support 106 adapted to receive a stack of sheets or bills to be dispensed. A sheet retainer 108 is supported on a pivot 110 carried by a bracket 112 pivotally mounted on the frame. Bracket 112 also carries a sheet stripper assembly 114 which cooperates with the feed roller 52 to ensure that only one sheet at a time is dispensed.
We form the platform 106 with a pair of lower curved guide portions 107, one of which can be seen in FIG. 1, extending around shaft 44 inside of the outer peripheries of rollers 52 and outboard of the respective rollers. A curved guide 116 cooperates with the feed rollers 52 to guide the leading edge of a sheet to the nip between the acceleration rollers 54 and 62. The operation of the feed rollers 52, shoes 114 and acceleration rollers 54 and 62 in advancing sheets, is more fully described in U.S. Pat. No. 4,474,365 issued Oct. 2, 1984. Sheets delivered by the accelerating rollers 54 and 62 are guided into the nips between belts 88 and 90 and rollers 100 and 102 by a guide 118.
The ones dispensing unit 40 supported on the upper frame section 32 includes a support platform 120, feed rollers 122 and 124, an upper idling accelerator roller 126, a lower accelerating roller 128, strippers 130 and a picker roller 134, all of which function in substantially the same manner as do corresponding elements of the unit 42. The shaft 136 which supports the lower accelerating roller 128 carries a pulley 138 adapted to be driven in a manner to be described to drive the elements of the unit 40.
Belts 88 and 90 extend around respective grooves in an upper drive through roller 142 rotatably supported on a stationary shaft 140. We loosely mount the ends of shaft 140 in the sides 36 and 38 to permit it to be biased to an operative position by respective springs 141 and 143.
The structure thus far described is assembled with the upper frame section 42 before the two frame sections are secured in cooperative relationship. We have found that this operation greatly facilitates the manufacture of the completed assembly.
A motor 144 having a shaft 146 supported in a side wall 28 of the lower frame section 24 carries a pulley 148 which drives a belt 150. When the two frame units 24 and 32 are assembled in cooperative relationship the belt 150 is engaged with the pulley 68 so that upon energization of the motor 144 the fives dispensing unit 42 is driven.
A second motor 152 has a shaft 154 supported in wall 28. Shaft 154 carries a pulley 156 which drives a belt 158. When the apparatus is assembled, belt 158 is engaged with pulley 138 so that upon energization of motor 152 pulley 138 is driven to cause the ones dispensing unit to operate.
A third motor 160 having a shaft 162 rotatably supported in side 28 is adapted to drive a pulley 164 which receives a belt 166. Belt 166 is adapted to drive a pulley 168 carried by a shaft 170 rotatably supported in the sides 28 and 30 of the lower frame section. Shaft 170 carries a lower feedthrough roller 172 which cooperates with roller 142 to advance sheets o the stacker mechanism to be described.
Shaft 162 carries a second pulley 174 which drives a belt 176 extending around an idler pulley 178 rotatably supported on a stub shaft 180 carried by side 28. A second smaller diameter pulley 182 on shaft 180 drives a belt 184 which extends around a second idler pulley 186 rotatably supported on a stub shaft 188 carried by the side 28. A second pulley 190 on shaft 188 drives a belt 192 which extends around a pulley 194 carried by the stacker shaft 196 rotatably supported in bearings 198 and 200 in the sides 28 and 30 of the lower frame unit. Shaft 196 carries for rotation therewith a pair of spaced stacker wheels 202 and 204. Referring to FIG. 5, a slotted guide 206 receives the sheets delivered by the rollers 142 and 172 to be acted upon by the stacker wheels 202 and 204, and thus delivered to the output tray 208 of the apparatus.
The apparatus includes a push button and display unit indicated generally by the reference character 210 located behind a window 212 formed in an extension of the front part of the top 20.
When the various components save for the belts 150 and 158 have been assembled in the upper and lower halves 32 and 24 in the manner described hereinabove, the upper section 32 is placed on the lower section so that pairs of lugs 205,207 and 209,211 secured to the respective sides 36 and 38 at spaced locations along the lower edges thereof overlie sides 28 and 30. Bolts 213 and nuts 215 hold the sections assembled. It will readily be appreciated that this construction not only facilitates the manufacture of our dispenser but also enables servicing and repair to be expeditiously accomplished merely by separating the sections.
When the upper and lower sections are assembled in the manner described the roller 142, which is carried by the biased shaft 140, moves into engagement with roller 172 to provide a driving engagement therebetween. Under this condition the action of the clutch bearings 83 and 85 come into play. If motor 160 is energized so that shaft 170 is driven at its normal speed, clutch bearings 83 and 85 are overrun. If, however, motor 160 is not energized while bills are being delivered from unit 42, the bearings engage so that roller 142 drives roller 172 and the stacker mechanism. In this way bills are prevented from piling up.
We provide our dispenser with a plurality of sensor pairs for affording indications of various conditions of the apparatus. A first sensor pair including a light source 214 and a phototransistor 216 may be employed to sense the presence of a supply of ones on the tray or platform 120. Light received by phototransistor 216 directly from the source 214 produces a signal indicating absence of any ones on the support 120.
A light source 220 and a phototransistor 222 responsive to light from the source 220 provide a signal indicating that the supply of ones on the support has dropped to below a predetermined level. One of the elements 220 and 222 is placed at one side of the stack and the other at the other side of the stack so as to operate on light received directly from the source.
A source 224 of light arranged at one side of the path followed by a one dollar note being delivered by the roller 124 causes a photodiode 226 to produce an output signal which indicates not only that a bill has been fed, but which also provides a measure of the amount of light transmitted by the bill so as to afford an indication of a double feed in a manner known to the art.
A light source 236 cooperates with a sensor, such as a phototransistor 238, by directing radiation through a window 240 in the platform 106, so that radiation received by element 238 indicates the absence of a stack of bills on platform 106.
Another sensor set including a light source 242 and a detector, such as a phototransistor 244, operates on direct illumination to afford an indication that the stack of fives on the support 106 has fallen to below a predetermined level.
A source 246 and a infrared diode element 248, such as a photodiode, mounted respectively on the curved portion 107 of the platform 106 and on the curved guide 116, afford an indication of the amount of radiation passing through the bill, thus to enable us to generate not only a count signal but also a signal indicating a double feed.
Referring to FIGS. 2 and 12, a sensor pair including a light source 228 and a phototransistor 230 cooperate with an encoder wheel 232 on the shaft carrying roller 128 so that the teeth 234 of the wheel generate a train of pulses affording a measure of the length of a note being dispensed by the ones unit. A second sensor pair including a light source 250 and a light sensitive element, such as a phototransistor 252, cooperate with an encoder wheel 251 on shaft 56 so that the teeth 253 of the wheel 251 passing through the space between the elements 250 and 252, causes the generation of a train of pulses affording a measure of the length of a note being dispensed by the fives unit.
Referring now to FIG. 5, we provide our dispenser with means for generating a "verify" signal indicating the fact that a note being fed by a dispenser 40 or 42 has, in fact, reached the stacker wheel 204. We mount a suitable light source 254 on a bracket 256 carried by the upper frame member. Light from the source 254 extends across the path of movement of a one travelling from the unit 40 toward the stacker wheels. This light, after having traversed the one's path, crosses the path of a five being delivered by the rollers 142 and 172 to the stacker. A sensing device 262 supported by guide 118 on the other side of the five's path receives the light. Owing to the fact that this arrangement is common to both the one's path and the five's path and that both the one's delivery and five's delivery units 40 and 42 do not operate at the same time, we are able to achieve the verification signal by the use of only a single pair of elements.
Finally, we provide the output tray 208 with a pair of sensing elements comprising a light source 261 and a light sensitive element 263 such as a photodiode for detecting the presence of one or more bills in the output tray. As will be explained more fully hereinbelow, we employ this signal to inhibit further operation of the machine under certain conditions until the bills have been removed from the output tray.
In some installations it may be necessary or desirable to position the dispenser unit below the surface counter and yet provide for delivery of the bills at or adjacent to the countertop.
Referring now to FIGS. 6 and 7, we have shown an alternate embodiment of our simplified currency dispenser in which we secure a top delivery unit indicated generally by the reference character 276 to the front of the assembled top and bottom sections 32 and 34 of the machine. This may be accomplished by any suitable means known to the art. As will be apparent from the description hereinbelow, this top delivery unit 276 replaces the lower stacker wheels 204 and 206 and the lower delivery tray 208, as well as the display panel 210 of the form of our simplified currency dispenser shown in FIGS. 1 to 5.
The unit 276 includes a pair of side panels 278 and 280 which rotatably support a shaft 282 by means of bearings 284 and 286. Shaft 282 carries for rotation therewith a pair of spaced stacker wheels 288 and 290 for delivering bills to a tray 291 located near the top of the apparatus. Shaft 282 also carries a pulley 292 connected by a belt or 0-ring 294 to the drive pulley 190 carried by shaft 188. It will readily be appreciated that some slight rearrangement of the axes of rotation of the pulleys shown in FIG. 4 may be necessary to prevent interference between the belt 294 and other elements.
When employing the top delivery unit 276, we provide a guide or guides 296 forming an extension of the guides 118 directed generally upwardly towards the stacker wheels 288 and 290 and guides 297 extending around the axis of shaft 282. A pair of belts 298 and 300 extending around rollers 172 are guided around respective relatively larger diameter pulleys 302 and 304 rotatably supported on shaft 282 at positions spaced inboard of the stacker wheels 288 and 290.
It is to be understood that the drive system associated with the top delivery unit 276 is substantially the same as that of the form of our invention shown in FIGS. 1 to 5 in that the belts 298 and 300 are driven at a greater speed than are the stacker wheels 288 and 290 so that bills are positively forced into the spaces between adjacent fingers of the stacker wheels.
We provide respective first hold-down rollers 306 and 307, for the belts 298 and 300. Respective pairs of idler rollers 308 and 310 and 312 and 314 associated with the respective belts 298 and 300 prevent bills from flying away from those portions of the belts extending from the location at which ones are fed upwardly toward the stacker wheels 288 and 290.
From the structure just described, it will readily be apparent that in operation of the form of our currency dispenser shown in FIGS. 6 and 7, bills delivered by the fives unit 42 are received by the upper surfaces of the belts 298 and 300, as viewed in FIGS. 6 and 7, pass under rollers 306 and 307 and are carried upwardly under the pairs of idler rollers 308 and 310 and 312 and 314 and are fed into the pockets formed by adjacent fingers of the stacker wheels 288 and 290. Bills fed by the ones unit 40 are received by belts 298 and 300 at the location between roller 306 and roller 308, as viewed in FIG. 6. Further, as is pointed out hereinabove, the belts 298 and 300, are driven at a somewhat faster speed than the surface speed of the stacker wheels 288 and 290 so that bills are positively forced into the spaces between adjacent fingers of the stacker wheels 288 and 290. As the stacker wheels continue to rotate, they lay successive bills down on a tray 316 from which they can be retrieved bY the operator of the dispenser. It is to be understood that when the form of our currency dispenser illustrated in FIGS. 6 and 7 is installed below the counter at the establishment at which it is located, bills on the tray 316 are accessible at a location just below the top of the counter.
Referring now to FIG. 8, the built-in keypad and display panel 210 includes a plurality of numerical pushbuttons 264 which may be actuated to enter information as desired. A START-CLEAR button 266 is actuated to set the unit in the count mode while COUNT, BATCH and RESET buttons 268, 270 and 272 are actuated to control the operation in the count mode. A display 274 gives a visual indication of output information.
Operation of our apparatus in the dispense mode is controlled by a remote or point-of-sale keypad and display unit, indicated generally by the reference character 372. Unit 372 includes a keypad having numerical input keys 373, as well as NET SALE, AMOUNT TENDERED and DISPENSE keys 374, 375 and 376. A display 378 affords a visual indication of output information in the dispense mode.
Referring now to FIG. 9, we have shown the relationship between the central processing unit indicated generally by the reference character 488 of our apparatus, to be described more fully hereinbelow, and various sources of input information such as the keyboard, the empty supply signal generators, the low supply signal generators, the count and doubles signal generators, the encoders, the verify sensor and the output tray sensor. The central processing unit uses this information in a manner to be described more fully hereinbelow to actuate the display, the motor drives and a coin dispenser, if one is so provided.
Referring now to FIGS. 10 to 13, in the analog portion of the control system of our dispenser, a voltage divider made up of resistors 380 and 382 provides a reference potential which is applied to the inverting terminals of operational amplifiers 384, 386, 388, 390, 392 and 394, associated with the phototransistors 216, 238, 222, 244, 263, and 262. When, for example, light from the diode 214 impinges on the base of transistor 216, the transistor conducts to apply a signal to the non-inverting input of amplifier 384 to indicate that there are no documents in the ones supply tray. Conversely, when a supply of documents is present the nature of the signal on line 396 indicates this fact. Respective output lines 398, 400, 402, 404 and 406 associated with the respective amplifiers 386, 388, 390, 392 and 394 indicate the presence or absence of $5 notes in the $5 input tray, the fact that the stack of ones has or has not reached a predetermined low point, the fact that the stack of fives has or has not reached the predetermined low point, the presence or absence of notes in the stacker tray and a signal indicating that notes dispensed have, in fact, been fed to the stacker.
As has been pointed out hereinabove, we provide a pair of sensors including LEDs 224A and 224B and photodiodes 226A and 226B for producing signals from which a count of the number of ones dispensed may be obtained and from which there is indicated the presence of overlapping bills. Respective feedback networks including transistors 408 and 410 operate to maintain the output level of light from the LEDs 224A and 224B, substantially constant in a manner known to the art. A reference potential is applied to the inverting input of a COUNT operational amplifier by means of a voltage divider made up of resistors 416 and 418. When the light from LED 224A is interrupted, the signal is applied to an input resistor 420 at the non-inverting input of amplifier 412 to produce a COUNT Al signal on an output line 422. In a similar manner, an operational amplifier 414 associated with diode 226B provides a COUNT B1 on line 424. Another operational amplifier 426 responsive to the condition of diode 226A provides an input to operational amplifier 430 to generate a DOCSIG A1 on line 434. Similarly, an operational amplifier 428 responsive to the condition of diode 226B provides a signal for an amplifier 432 to generate a DOCSIG B1 on line 436.
The pair of sensors including LEDs 246A and B and diodes 248A and 248B associated with the $5 note dispensing system are employed to generate signals similar to those described hereinabove in connection with the dispensing of one dollar notes. Respective feedback circuits including transistors 438 and 440 maintain the output light levels of LEDs 246A and 246B substantially constant. Respective operational amplifiers 442 and 444 associated with diodes 248A and 248B provide COUNT A5 and COUNT B5 outputs on lines 446 and 448. Operational amplifiers 450 and 452 are responsive to the conditions of diodes 248A and 248B, actuate amplifiers 454 and 456 to provide DOCSIG A5 and DOCSIG B5 signals on lines 458 and 460.
As shown in FIG. 12, LED 228 is so arranged with reference to wheel 232 and teeth 234 as intermittently to cause light to impinge upon the base of transistor 230 to generate an ENCODE signal for ones. A similar circuit responsive to the output of transistor 252 provides an ENCODE signal for fives.
FIG. 13 illustrates one form of control circuit which may be used to control the 1's and 5's dispensing motors 152 and 144 and the stacker motor 160 by connecting them to a suitable source of DC potential having a terminal 462. A STACKER signal on line 464 renders a transistor 466 conductive to apply the potential at terminal 462 to the motor 160.
A FEED 1 signal on line 468 causes a transistor 470 to apply the potential of terminal 462 to the motor 152. A BRAKE 1 signal on the line 472 renders a transistor 474 conductive to connect a shunt resistor 476 across the motor 152 to brake the motor after the feed signal disappears.
A FEED 5 signal on a line 478 causes a transistor 480 to apply the potential at terminal 462 to the motor 144. After the feed signal disappears, a BRAKE 5 signal on a line 482 renders the transistor 484 conductive to connect a shunt resistor 486 across motor 144 to brake the same.
Referring now to FIGS. 14 to 18, the central processing unit 488 includes a microprocessor 490 such as a Z-80 manufactured by Zilog, Inc. of Campbell, Calif., having a non-maskable interrupt terminal 492 which receives a signal in the event of a power failure, as is known in the art. The microprocessor 490 receives reset pulses at a reset terminal 494 and clock pulses from a suitable pulse generator (not shown) at a terminal 496.
As will be described more fully hereinbelow, in response to the system clock/pulses, the microprocessor feeds address information to a pair of bidirectional buffer circuits 498 and 500 such, for example, as 74HC244 which translate the information to an address bus 502.
Bus 502 feeds the address information into a PROM, such as a TMSC 27256, a counter timer circuit 506, a RAM circuit 508 such as a CDN 6264, a pair of parallel input/output circuits 510 and 512, a serial input/output circuit 514, a third parallel input/output circuit 516 and a second counter timer circuit 518. At the appropriate times, the circuits 506, 508, 510, 512, 514, 516 and 518 feed output data to a data bus 520 leading back to the microprocessor 490.
Respective decoders 522 and 524 which may be 74HC138 circuits respond to information on the address bus selectively to enable various of the circuit chips.
Outputs I01 and I04 to I07 respectively enable chips 510, 518, 512, 516 and 514. I02 provides one input to a 2-input circuit OR 526 coupled to the enable terminal of a buffer/driver/receiver 528, which may be a 74HC244, the function of which will be described more fully hereinbelow. I03 provides an input to the CS terminal of an analog to digital converter 540.
The signal on output line 530 of decoder 524 enables chip 506. Lines 532 and 534 carry signals which clock respective octal flip-flops 536 and 538 which may be 74HC374 chips to couple data from the bus 502 to the display in a manner to be described.
A line 542 provides a clock pulse input to a buffer/driver/receiver circuit such as a 74HC244 to couple the input/output request IORQ, the memory request MREQ, memory read RD, memory write WR and M1 system control output terminals of the microprocessor 490 to respective output lines 546 and 548, 550, 552, 554 and 556 and the halt state HALT output terminal of the microprocessor to a line 560.
Lines 550 and 556 provide inputs for an AND circuit 568, coupled to the enable terminal of a transceiver 566, such as a 74HC245. Lines 546 and 556 provide inputs for an OR circuit 562, the output of which is applied to an AND circuit 564, together with the signal on line 552 to supply an input to the directional input terminal of the transceiver 566. The memory request signal on line 550 provides one input for an OR circuit 570, the other input of which comes from an address bus 502 to provide a signal input for the chip enable terminal of PROM 504. The memory read signal on line 552 is applied to the output enable terminal of memory 504.
The CTC 506 which is enabled by line 530 also receives inputs from the M1 input/output request and read lines 556, 546 and 552.
Referring now to FIG. 15, the M1, IOREQ, RD and SYS CLK lines 558, 548, 552 and 496 lines provide inputs to the parallel input/output circuits 510 and 512. Circuit 512 receives condition input signals from lines 396, 398, 400, 402, 404, 422, 424, 446 and 448. The circuit 510 receives inputs from keyboard switches 572a to 5721. Switches 572a to 572f correspond to amounts while 572g to 1 respectively correspond to COUNT, REMIT, DOUBLE, CONTINUE, STOP and START/CLEAR.
The MREQ signal on line 550 provides one input for an OR circuit 574 which receives its other input from the address bus 502 through an inverter 576 to provide a CS1 input for RAM 508. The RD signal on line 552 provides the output enable signal for chip 508.
Referring now to FIG. 16, the M1, IOREQ and RD signals on lines 558, 548 and 552 provide inputs for circuits 514, 516 and 518. Conductors 576 and 578 leading from chip 506 provide inputs for SIO 514. Chip 518 receives respective inputs from the fives encoder wheel and ones encoder wheel on lines 580 and 582.
Chip 516 provides the motor control signals described hereinabove on conductors 464, 468, 472, 478, and 482. An output 584 of chip 516 controls a suitable acoustical device 586 to indicate that the supply of currency being dispensed is exhausted. Other outputs of chip 516 indicate a power on condition at a terminal 588, a ones low condition at a terminal 590 and a fives low condition at a terminal 592. These terminals may be connected to suitable indicators.
In addition, the chip 516 puts out DOC A5 and DOC A1 signals on lines 594 and 596, as well as DOC B5 and DOC B1 signals on lines 598 and 600.
Referring to FIG. 17, we apply the signals on conductors 434, 436, 458 and 456 to respective microprocessor operated switches 602, 604, 606 and 608. Respective inverters apply the signals on lines 596, 600, 594 and 598 to the switches 602, 604, 606, and 608 to couple the signals on line 434, 436, 458 and 456 to the analog's digital converter 540. In addition to the I03 signal from chip 522, the converter 540 receives write and read signals on lines 552 and 554.
Turning now to FIG. 18, switches 610a to 610hprovide inputs for chip 528 to set up the particular software which is to be used. More specifically, the switches are so operated as to tell the microprocessor, for example, whether it is hooked up to a point of sale terminal or to the remote key pad.
The first octal flip-flop 536 which is clocked by the signal on line 534 feeds signals DBL, B100, B50, B25, B20, B10 and B5 to respective LEDs 614a to 614g.
The second octal flip-flop 538 which is clocked by the signal on line 532 provides respective output signals DIG4, DIG3, DIG2, DIG1, BCD8, BCD4, BCD2 and BCD1 leading to the display board illustrated in FIG. 19.
Referring now to FIG. 19, we apply inputs as indicated to circuit components 618 and 620 to provide four groups of outputs indicated as al to gl, a2 to g2, a3 to g3 and a4 to g4, to illuminate LEDs making up a four digit number.
Referring now to FIGS. 20 through 29, we have shown the flow chart of the program which controls our apparatus. Beginning at START in FIG. 20, the RAM 508 is first tested. If this test is unsuccessful, as indicated by SYSERR, proceed to FIG. 24 display "Help" and halt the program. If the test is successful, the input/output circuits, the RAM and the INTERRUPTS are initialized. Next, the display is actuated to show an indicating designation, such for example as "8902" which may be the model number of the apparatus. In addition, the pending INTERRUPTS are cleared and the timer circuits are set.
When the above has been accomplished, the program is at "BEGIN". The first determination to be made is whether or not the apparatus is in the COUNT mode. As has been pointed out hereinabove, the system normally is in the dispense mode. It is placed in the count mode by actuating the START/CLEAR button 266. If the answer is yes, proceed to FIG. 26 and continue in a manner to be described hereinbelow. Assuming that the system is not in the COUNT mode, proceed to "DISPENSE" in FIG. 21. The DIP switches 610a to 610h are read and the interface selected. When that has been done a determination is made if the supply of ones or of fives is low. If so, "LO" is displayed one second from the last display and the system returns to "BEGIN" in FIG. 20.
If neither the supply of ones nor the supply of fives is low, a check is again made to see if the switch is set to the COUNT mode. If so, as before, the system proceeds to the "COUNT MODE" of FIG. 26. If the switch is not set to the COUNT mode, a check is made to determine whether or not the data from the keyboard or other source has been read in. If not, the system returns to the ones or fives pocket low decision. If the data has been read in, proceed to "CALCULATE" in FIG. 22. At this point, the amount to be dispensed is displayed and a calculation is made of the number of ones and the number of fives required to make up that amount. For example, if $18.00 is to be dispensed, a calculation is made that three ones and three fives are to be dispensed for a total of documents or bills of six.
Next, a check is made to determine if the system has called for more than twenty documents to be dispensed. If so, the system goes to "ERRORS" in FIG. 25, displays "Help" and halts the program.
If the system indicates that not more than twenty documents have been called for, a decision is made as to whether or not any fives are to be dispensed. If so, a check is made to determine whether or not there are any fives in the supply tray. If so, a five dollar note is dispensed and the system proceeds to determine whether or not any errors have occurred. If so, the system again proceeds to FIG. 25 to display "Help" and halt the program. If no errors have occurred, the system returns to the determination of whether or not there are any fives to dispense. If more fives are to be dispensed, a check again is made if there are any fives in the pocket. If so, another five is dispensed and the system proceeds.
When no more fives have been called for, the system proceeds to the "DISPENSE 1's" terminal of FIG. 23. It is to be noted that if the system calls for a five to be dispensed and no fives remain in the supply, the amount of leftover fives is added to the number of ones required to be dispensed before the system proceeds to the "DISPENSE 1's" terminal of FIG. 23.
Prior to dispensing the number of ones called for, a check is made to determine whether or not more than twenty documents are required. If so, the system returns to FIG. 24, displays "Help" and halts the program. If no more than twenty documents have been called for, a check is made to see whether or not there are any ones to be dispensed. If so, the system proceeds to determine whether or not there are available any ones in the supply. If not, the dispensing operation called for obviously cannot be fulfilled and the system goes back to FIG. 4, displays "Help" and halts the program. If there are ones available to be dispensed, a one is dispensed and a check is made to see if any errors have occurred. If an error has occurred, the program proceeds to FIG. 24 to cause "Help" to be displayed and to halt the program. If no error has occurred, the program returns to the decision of whether or not any ones are to be dispensed. If so, it proceeds as before. If not, the dispensing operation ostensibly is complete and the program proceeds to the "DISPENSE CHECK" terminal of FIG. 25.
From the "DISPENSE CHECK" terminal, a decision is made as to whether or not any errors have occurred. If no errors have occurred, the system returns to "BEGIN" in FIG. 20. If an error has occurred, the offending error or errors are displayed. Examples of errors which might be detected are "half note" where a piece of a bill which has been torn into two pieces is detected and "chain note" indicating that overlapping bills have passed through. These errors are displayed on the display 378 as "E1" and "E2" or the like. At the same time a loud, pulsing and audible beep is generated. The system then checks to determine whether or not the output tray is empty. If not, the loud, pulsing and audible beep continues to be generated to alert the operator to empty the output tray before the system will proceed. If the output tray is empty, a determination is made of whether or not the error is unrecoverable. If it is an unrecoverable error, the program returns to "BEGIN" in FIG. 20. If the error is recoverable, it returns to the "CALCULATE" terminal in FIG. 21.
Assuming that the system had been set in the COUNT mode as indicated by the decision box in FIG. 20 so that the program proceeded to the "COUNT" mode terminal of FIG. 26, first the count is cleared and the doubles detection is set on. A determination is then made of whether or not the START key has been pressed. If so, the program proceeds to the "C-START" terminal of FIG. 28. At this point the system first clears the count and resets the batch count. Next, errors are cleared. A determination then is made of whether the count is higher than the batch. If so, the count and batch count are reset, a document is moved from the input tray to the output tray, and the display and batch count are bumped. If a determination had been made that the count was not higher than the batch count, the program proceeds directly to dispense a document and bump the display and batch counts. After a document has been dispensed and the display and batch counts bumped, the system proceeds to the "C-CHECK" terminal of FIG. 29.
A check of the doubles detector is made to see whether or not an error has occurred. If not, the system proceeds directly to determine whether or not any other errors have occurred. If a doubles error is indicated, a check is made to see whether or not the doubles detection system is active. If not, the system proceeds to determine whether or not any other errors exist. If the doubles detection system is active and a double errors has been indicated, the program proceeds to display the error and stop the counter. If there is no doubles error or the double detection system is not active and another error is not detected, the program proceeds to the "C-NEXT" terminal in FIG. 28 to continue the count.
If an error has been detected and the counter has been stopped, a check is then made to see if the output tray is empty. If it is, the program returns to the "C-BEGIN" terminal of FIG. 26. If an error has been detected and the output tray is not empty, a check is made to see whether or not the CONTINUE or START key is pressed. If not, the program returns to the determination of whether or not the output tray is empty. If an error has been detected and the output tray is not empty and one of the CONTINUE or START keys has been pressed, the system sounds a short beep to remind the operator to empty the output tray and the program returns to the determination of whether or not the tray is empty If the tray is empty, the program returns to the "C-BEGIN" terminal of FIG. 26.
If, following a determination that a system is in the COUNT mode, a determination also is made that the START key has not been pressed, the system makes a decision as to whether or not the continue key has been pressed. If so, the program goes to the "C-CONT" terminal of FIG. 28 leading to the clear errors operation and the program proceeds as before. If the CONTINUE key has not been pressed, a check is made to see whether the input tray has just now been filled. If so, the system checks to determine whether or not the stacker tray is full. If not, the program proceeds to the "C-START" terminal of FIG. 28. If the stacker tray is full the program proceeds to the "C-CONT" terminal of FIG. 28.
If, following a determination that neither the START key nor the CONTINUE key has been pressed and the input tray has not just now been filled, the program goes to the "C-KEYS" terminal of FIG. 27. A determination is then made of whether or not a batch key has been pressed. If so, the proper LED and appropriate batch counts are set and the program goes to the "C-BEGIN" terminal of FIG. 26.
If no batch key has been pressed, a check is made to see if the COUNT key has been pressed. If so, the batch count and batch LED are cleared and the system goes to the "C-BEGIN" block of FIG. 26.
If neither the batch key nor the count key has been pressed, a check is made to see if the double key has ben pressed. If so, the doubles detection status and LED are toggled and the program goes back to the "C-BEGIN" block of FIG. 26. If none of the batch keys or the count key or the double key is pressed, a check is made to see whether or not the stop key is pressed. If, under these conditions, the stop key has not been pressed, the system checks to see if the reset key has been pressed. If so, the program returns to the START terminal of FIG. 20. If the stop key has been pressed, a short beep is sounded and the program returns to the "C-BEGIN" block of FIG. 26. If neither the stop key nor the reset key has been pressed, the program returns to the C-BEGIN block of FIG. 26. If the stop key is not pressed but the reset key has been pressed, the program returns to the START block of FIG. 20.
The operation of our simplified currency dispenser will be apparent from the description given hereinabove. In the normal operation of the device in the dispense mode, wherein change is to be given to a customer in response to payment for merchandise, the operator first punches in the cost of the purchase on keys 373. The aggregate is displayed. Next, the amount tendered by the customer is entered and displayed and the display then shows the amount to be given in change. The amount in bills is determined in terms of the number of five dollar bills and the number of one dollar bills required to make the change. Where there are not enough five dollar bills to make up the required number, a number of ones equal to the same amount is added to the number of ones to be dispensed. The unit then operates first dispensing five dollar bills from unit 42 and then dispensing one dollar bills from unit 40 until the required amount of bills in change has been delivered to the output tray 208.
To cause the unit to operate in the count mode, the START CLEAR button 266 is pressed to set it in the count mode. The bills to be counted then are placed on the tray 120 and the unit begins to count. It may be operated in the batch count mode.
In the course of dispensing or counting operations, errors are detected and displayed on the operative display as coded signals.
It will be seen that we have accomplished the objects of our invention. We have provided a simplified currency dispenser which is especially adapted for use at a location at which a high volume of relatively low dollar amount transactions are being carried out. Our simplified currency dispenser is accurate and reliable. It is simple, compact and inexpensive. It is relatively easy to construct and to service.
It will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations. This is contemplated by and is within the scope of our claims. It is further obvious that various changes may be made in details within the scope of our claims without departing from the spirit of our invention. It is, therefore, to be understood that our invention is not to be limited to the specific details shown and described. | A simplified currency dispenser especially adapted for use at high volume low dollar amount transaction locations. The dispenser is adapted alternatively to transport a selected mix of currency notes from first and second supplies to a delivery location and to display the dollar value of the delivered notes or to transport notes from only one of the supplies to the delivery location and to display the number of notes transported. The dispenser includes a first key pad and display on the dispenser housing for use during a counting operation and a remote key pad and display for use during a dispenser operation. The housing is made in upper and lower sections for ease of manufacture and servicing. It is adapted for either countertop installation or below the counter installation. | 6 |
CROSS-REFERENCE TO RELATED APPLICATION
This is continuation-in-part of application U.S. Ser. No. 694,363 filed Jan. 24, 1985, now abandoned, which in turn is a continuation-in-part of application U.S. Ser. No. 581,836 filed Feb. 21, 1984, now abandoned.
INTRODUCTION
This invention relates to new synthetic chemical compounds somewhat related to the antibiotic/antitumor agent CC-1065. More particularly this invention provides new compounds such as (7bR, 8aS)-1,2,8,8a-tetahydro-7-methyl-2-[[5-(((2H-indol-2-yl)carbonyl)amino)-1H-indol-2-yl]carbonyl]cyclopropa[pyrrolo[3,2-e]indol-4(5H)-one (U-71,184) as purified, and in its essentially racemic form (U-68,415), and related intermediate compounds.
BACKGROUND OF THE INVENTION
Antibiotic CC-1065 is disclosed and claimed in L. J. Hanka et al U.S. Pat. No. 4,169,888 together with a process for preparing antibiotic CC-1065 by aerobic fermentation procedures, and recovering antibiotic CC-1065 therefrom.
In J. Am. Chem. Soc., 103, No. 18, 1981, W. Wierenga published a "Synthesis of the Left-Hand Segment of the Antitumor Agent CC-1065".
Wierenga U.S. Pat. No. 4,400,518 claims some new compounds of the formula ##STR2## wherein R 2 and R 3 are hydrogen, C 1 to C 5 alkyl, or phenyl;
R 4 is --SO 2 R 2 , --SO 2 CH 2 C(O)phenyl, --CO 2 CH 2 Z where
Z is --CH 2 I, --CCl 3 , --CH 2 SO 2 R 2 , phenyl or fluorenyl;
X is --OSO 2 R 2 , Cl, Br or I,
with the proviso that R 2 cannot be hydrogen when it is adjacent to --SO 2 .
Wierenga U.S. Pat. No. 4,413,132 claims some compounds of the formula ##STR3## where R 1 is methyl, benzyl, allyl, methylthiomethyl, methoxymethyl, methoxyethoxymethyl, 2,2,2-trichloroethyl, or (R 2 ) 3 -Si-ethyl,
R 2 and R 3 are hydrogen, C 1 to C 5 -alkyl, or phenyl;
R 4 is --SO 2 R 2 , --SO 2 CH 2 C(O)phenyl, --CO 2 CH 2 Z where
Z is iodomethyl, trichloromethyl, --CH 2 SO 2 R 2 , phenyl or fluoroenyl; and
X is --OSO 2 R 2 , chloro, bromo or iodo, with the proviso that R 2 cannot be hydrogen when it is adjacent to --SO 2 .
Wierenga U.S. Pat. No. 4,423,228 claims a process for preparing an intermediate compound of the formula ##STR4## by reacting its 1-methanol pecursor with triphenylphosphine/carbon tetrahalide, and then recovering the above cyclopropa- compound from its reaction mixture.
Wierenga U.S. Pat. No. 4,423,229 claims a process for preparing a compound of the formula ##STR5## where R 2 and R 3 are hydrogen, C 1 to C 5 -alkyl or phenyl;
R 4 is --SO 2 R 2 , --SO 2 CH 2 C(O)phenyl or --CO 2 CH 2 Z where
Z is iodomethyl, trichloromethyl, --CH 2 SO 2 R 2 , phenyl or fluorenyl; by cyclizing its halomethyl or its methanesulfonate ester precursor compound.
Wierenga U.S. Pat. No. 4,423,230 claims a process for preparing a compound of the formula ##STR6## where R 2 and R 3 are hydrogen, C 1 to C 5 -alkyl, or phenyl;
R 4 is --SO 2 R 2 , --SO 2 CH 2 C(O)phenyl, or --CO 2 CH 2 Z where
Z is iodomethyl, trichloromethyl, --CH 2 SO 2 R 2 , phenyl or fluorenyl, and
Z is --OSO 2 R 2 , chloro, bromo or iodo, with the proviso that R 2 cannot be hydrogen when it is adjacent to --SO 2 .
Wierenga U.S. Pat. No. 4,424,365 claims compounds of the formula ##STR7## in the keto or enol form, where
R 2 and R 3 are hydrogen, C 1 to C 5 -alkyl or phenyl;
R 4 is --SO 2 R 2 , --SO 2 CH 2 C(O)phenyl, or --CO 2 CH 2 Z where
Z is iodomethyl, trichloromethyl, --CH 2 SO 2 R 2 , phenyl or fluorenyl.
OBJECTS OF THE INVENTION
It is an object of this invention to provide some new, synthetically obtained 1,2,8,8a-tetrahydrocyclopropa[c]pyrrolo[3,2-e]indol-4)5H)-one derivative compounds which new compounds are useful as ultraviolet light absorbers and as antibacterials, and some of which are of interest for development as antitumor drug compounds for use as part of the therapy for treating some types of cancer in valuable animals and humans.
It is a further object of this invention to provide the art with the resolved stereo forms of selected compounds of the above type which resolved enantiomers have been found to possess the bulk of the important antitumor activity in standard laboratory animal tests.
Other objects of this invention will be apparent from the specification and the claims which follow.
SUMMARY OF THE INVENTION
This invention provides some new synthetically obtained 1,2,8,8a-tetrahydrocyclopropa[c]pyrrolo[3,2-e]indol-4(5H)-one derivative compounds of formulas I or II (see General Formulae Chart), as defined hereinafter, which are useful as light absorber substances, as antibacterial compounds, or as chemical intermediates the light absorbing or antibacterial compounds. Representative formula I compounds have also been shown to possess useful ranges of antitumor activity in standard laboratory animal tests. Two lead compounds within formula I, U-68,415 and its purified enantiomer U-71,184, have been selected for advanced testing for this antitumor drug utility. The compounds of this invention are obtained by chemical processes shown in Chart I and detailed in the examples.
DETAILED DESCRIPTION OF THE INVENTION
More specifically, this invention provides new chemical compounds of general formulae I and II (see GENERAL FORMULAE sheet)
wherein
R 1 in formula II is CH 3 --, --CH 2 Ph, CH═CHCH 2 --, --CH 2 SCH 3 , --CH 2 OCH 3 , --CH 2 OCH 2 CH 2 OCH 3 , --CH 2 CCl 3 , --CH 2 CH 2 Si(R 2 ) 3 , or H, where Ph is phenyl;
R 2 is alkyl(C 1 -C 5 ), phenyl, or H;
R 2 ' is C 1 to C 5 -alkyl, phenyl or hydrogen, and is not necessarily the same as R 2 in one compound;
R 3 is alkyl(C 1 -C 5 ), phenyl, or H;
X is Cl, Br, or I--, or OSO 2 R 40 , where R 40 is C1 to C 5 -alkyl, phenyl, tolyl, bromophenyl, nitrophenyl, or trifluoromethyl;
R 50 is hydrogen or the same as R 5 ;
R 5 is a carbonyl acyl group selected from the group consisting of
(i) ##STR8## where R 6 is H, --alkyl(C1 to C 20 ), --CCl 3 , CF 3 , or NH 2 ;
(ii) ##STR9## where X 1 and/or X 2 is H, CH 3 , OH, OCH 3 , NO 2 , NH 2 , NHAc, NHBz, or halogen;
(iii) acyl derivatives ##STR10## of the 20 natural amino acids where R 7 is the amino acid residue of glycine, alanine, valine, isoleucine, leucine, serine, threonine, aspartic acid, glutamic acid, lysine, arginine, asparagine, glutamine, cysteine, methionine, tryptophan, phenylalanine, tyrosine and histidine as well as proline (a ring containing acyl group formed by taking together the R 7 and --NH 2 moieties); and their common salts selected from Na.sup.⊕, K.sup.⊕, NH 4 .sup.⊕, CL.sup.⊖, PO 4 .sup.⊖ and OAc.sup.⊖ ;
(iv) ##STR11## where M.sup.⊕ is Na, K, NH 4 , or N(CH 3 ) 4 ; (v) ##STR12## where n 1 is 2-12; (vi) ##STR13## where X 3 and/or X 4 is H, OH, or OCH 3 ; (vii) ##STR14## where n 2 is 0-3; and R 8 is H, CH 3 or C 2 H 5 ; (viii) ##STR15## where X 5 is H, OH, OCH 3 , NO 2 , NH 2 , NHAc, ##STR16## NHBz; or NH--CN; and R 8 has the meaning defined above; (ix) ##STR17## where n 3 is 1 to 3; and R 8 and R 5 have the meanings defined above;
(x) ##STR18## where X 6 is H, NO 2 , NH 2 , NHAc, and ##STR19## (xi) ##STR20## wherein R 9 is CH 3 or NH 2 ; (xii) ##STR21## where R 8 and R 9 have the meanings defined above; (xiii) ##STR22## (xiv) ##STR23## where R 10 is --CH 3 , --PH, H.HCl; (xv) ##STR24## wherein R 11 is CH 2 CH 2 or CH═CH; and X 7 is --O--; NH; n 4 is 1-4; and the HCl and MeI salts when X 7 is NH;
(xvi) ##STR25## where R 7 and R 11 and n 4 have the meanings defined above; (xvii) ##STR26## where X 8 is --O--, --S--, NH; X 9 is --CH═ or --N═; and X 5 has the meaning defined above;
(xviii) ##STR27## where X 5 has the meaning defined above; (xix) ##STR28## where X 10 is --CH═ or --N═ and X 7 is SH, NH 2 , OH, H or NHAc;
(xx) ##STR29## where X 5 has the meaning defined above; (xxi) ##STR30## where X 5 and X 10 have the meanings defined above; and (xxii) ##STR31## where X 6 and R 8 have the meanings defined above; and when any of X 1 to X 6 is OH or NH 2 , then each of the R 5 groups represented above by ii, vi, viii, ix, x, xvii, xviii, xix, xix, xx, xxi or xxii may be coupled with each other forming the following dimer combinations wherein the representative R 5 groups are bound together via a carboxy ##STR32## or an amide ##STR33## linkage;
______________________________________ii + ii ix + xxii + vi ix + xxiii + viii ix + xxiiii + ix x + xii + xvii x + xviiii + xviii x + xviiiii + xix x + xixii + xx x + xxii + xxi x + xxiii + xxii x + xxiivi + vi xvii + xviivi + viii xvii + xviiivi + ix xvii + xixvi + x xvii + xxvi + xvii xvii + xxivi + xviii xvii + xxiivi + xix xviii + xviiivi + xx xviii + xixvi + xxi xviii + xxvi + xxii xviii + xxiviii + viii xviii + xxiiviii + ix xix + xixviii + x xix + xxviii + xvii xix + xxiviii + xviii xix + xxiiviii + xix xx + xxviii + xx xx + xxiviii + xxi xx + xxiiviii + xxii xxi + xxiix + ix xxi + xxiiix + x xxii + xxiiix + xviiix + xviiiix + xix______________________________________
Illustrative examples of the thus formed dimers are given below: ##STR34##
The compounds of formula (I) can be named as derivatives of the numbered ring system (A) shown on the GENERAL FORMULAE sheet. The wavy line bonds in the cyclopropa- ring of formula (A), including carbon atoms numbered 7b, 8 and 8a, are used to denote that the cycloproparing can be tilted (down) toward the alpha (α) direction or (up) beta (β) direction, relative to the plane of the ring system. An example of a specific epimer of this ring system, included in compounds of this invention can be named (7bR,8aS)-(1,2,8,8a-tetrahydro)-7-methyl-cyclopropa[c]pyrrolo[3,2-e]indol-4(5H)-one (U-71,150).
The compounds of formula II on the GENERAL FORMULA sheet can be named as derivatives of the numbering ring system (B) shown on the GENERAL FORMULAE SHEET. Such compounds will contain the 1,2,3,6-tetrahydro-3-R 5 -8-R 2 '-5-R 1 -benzo[1,2-b;4,3-b']dipyrrol-1-(R 3 -CH(X)-structure and X is as defined hereinabove. Examples of these Formula II compounds are described in the detailed examples hereinbelow, and the specific structures are shown in Chart I.
Examples of Formula I compounds of this invention include:
1,2,8,8a-tetrahydro-7-methyl-2-(quinolinylcarbonyl)cyclopropa[c]pyrrolo[3,2-e]indol-4(5H)-one (U-68,749);
1,2,8,8a-tetrahydro-7-methyl-2-(2-pyrrolylcarbonyl)cyclopropa[c]pyrrolo[3,2-e]indol-4(5H)-one (U-68,819);
1,2,8,8a-tetrahydro-7-methyl-2-[[5-benzoylamino-1H-indol-2-yl]carbonyl]cyclopropa[c]pyrrolo[3,2-e]indol-4(5H)-one (U-68,846);
1,2,8,8a-tetrahydro-7-methyl-2-[[5-[[5-benzoylamino-1H-indol-2-yl)carbonyl]amino]-1H-indol-2-yl]carbonyl]cyclopropa[c]pyrrolo[3,2-e]indol-4(5H)-one (U-68,880);
1,2,8,8a-tetrahydro-7-methyl-2-(1H-indol-2-ylcarbonyl)cyclopropa[c]pyrrolo(3,2-c]indol-4(5H)-one (U-66,694);
1,2,8,8a-tetrahydro-7-methyl-2-benzoylcyclopropa[c]pyrrolo[3,2-e]indol-4(5H)-one (U-66,866);
1,2,8,8a-tetrahydro-7-methyl-2-[(6-hydroxy-7-methoxy-1H-indol-2-yl)carbonyl]cyclopropa[c]pyrrolo[3,2-e]indol-4(5H)-one (U-67,785);
1,2,8,8a-tetrahydro-7-methyl-2-[[5-[[[1H-indol-2-yl]carbonyl]amino]-1H-indol-2-yl]carbonyl]cyclopropa[c]pyrrolo]3,2-e]indol-4(5H)-one (U-68,415);
(1,2,8,8a)-tetrahydro-7-methyl-2-2[[5-cyanoamino-1H-indol-2-yl]carbonyl]cyclopropa[c]pyrrolo[3,2-e]indol-4(5H)-one (U-69,058);
1,2,8,8a-tetrahydro-7-methyl-2-[[5-ureido-1H-indol-2-yl]carbonyl]cyclopropa[c]pyrrolo[3,2-e]indol-4(5H)-one (U-69,059);
1,2,8,8a-tetrahydro-7-methyl-2-[[5-[[[5-ureido-1H-indol-2-yl]carbonyl]amino]-1H-indol-2-yl]carbonyl]cyclopropa[c]pyrrolo[3,2-a]indol-4(5H)-one (U-69,060).
A compound of the above type which is being considered for advanced tumor reduction studies in the laboratory in the resolved enantiomer of U-68,415 above, (7bR,8aS)-1,2,8,8a-tetrahydro-7-methyl-2-[[5-[[[1H-indol-2yl]carbonyl]amino-1H-indol-2-yl]carbonyl]cyclopropa[c]pyrrolo[3,2-e]indol-4(5H)-one (U-71,184).
Chart I discloses the chemical steps to make the compounds identified therein and in Chart II. The process details of each step are given in the non-limiting examples which follow. With regard to each process step, the following delineates a fuller scope of the operating details. As used herein AC means carbonyl acyl; Bn means benzyl; Bz means benzoyl; Ph means phenyl; Ms means mesyl; and Me means methyl.
Chart II--Step 1: When R 4 is a sulfonamide, this N-deblocking transformation is effected by Red-Al (sodium bis-methoxyethoxy aluminum hydride) in THF/toluene or glyme [E. H. Gold and E. Babad, J. Org. Chem., 37, 2208-2210 (1972)]. This is described in detail for R 4 =SO 2 CH 3 in the following experiment.
When R 4 =SO 2 CH 2 COC 6 H 5 , the N-deblocking can be done by Zn/HOAc/trace HCl [J. B. Hendrickson and R. Bergeron, Tet. Lett., 345 (1970)]. When R 4 =CO 2 CH 2 CH 2 I the R 4 group can be removed by Zn/CH 3 OH at reflux [J. Grimshaw, J. Chem. Soc., 7136 (1965)]. Similarly, Zn/aq. THF, pH 4.2, can cleave R 4 =CO 2 CH 2 CCl 3 [G. Just and K. Grozinger, Synthesis, 457 (1976)]. Base (1M NaOH) cleaves R 4 =CO 2 CH 2 CH 2 SO 2 R 2 ([G. I. Tesser and I. C. Balvert-Geers, Int. J. Pept. Protein Res., 7, 295 (1975) and A. T. Kader and C. J. M. Stirling, J. Chem. Soc., 2158 (1964)]. The benzyl carbamate (R 4 =CO 2 CH 2 Ph) can be cleaved by hydrogenolysis [M. Bergmann and L. Zervas, Ber., 65, 1192 (1932)] or by one of many newer methods in the art such as TMS-I in CH 3 CN [r. S. Lott, V. S. Chauhan and C. H. Stammer, J. Chem. Soc., Chem., Commun., 495 (1979)]. The 9-fluorenylmethyl carbamate can be cleaved by ammonia or other simple amines [M. Brodanszky, S. S. Deshame and J. Martinez, J. Org. Chem., 44, 1622 (1979)].
Step 2: The indoline 2 can react with active acyl or sulfonyl compounds such as the chlorides or anhydrides, under conditions standard in the art (inert solvent such as ether or EtOAc; HX scavenger such as triethylamine) to effect the N-amidation. It can also be condensed with carboxylic acids in the presence of dehydrating agents such as carbodiimide. A convenient method for this approach is reaction of 2 with 1 equivalent of the carboxylic acid and 1 equivalent of EDC (ethyldimethylaminopropyl carbodiimide) in DMF [L. Grehn and U. Ragnarsson, J. Org. Chem., 46, 3492-3497 (1981)]. Alternatively, the condensation may be carried out with the commonly used dicyclohexylcarbodiimide in THF or DMF. It is not necessary to protect the alcohol functionality during this transformation.
Compounds 3 in which R 5 =i-vii (see Chart II) can be prepared from commercially available activated acyl compounds or carboxylic acids by procedures generally known in the art. For R 5 =viii, the acids with X 5 =H, OH and OMe are commercially available. The 5-NO 2 compound is prepared by Fischer cyclization of ethylpyruvate-p-nitrophenylhydrazone in polyphosphoric acid [S. M. Parmerter, A. G. Cook and W. B. Dixon, J. Amer. Chem. Soc., 80, 4621 (1958)]. This can be converted, by procedures standard in the art, to the NH 2 derivative (H 2 /PtO 2 ; Fe/HOAc) and thence to the NHAc(Ac 2 O), NHBz (PhCOOH, EDC, DMF), and ##STR35## derivatives. The ureido compound can be converted to the cyanamide with MSCl in pyridine. Alkylation of the indole nitrogen can be effected by procedures in the art such as NaH/CH 3 I or C 2 H 5 I.
For R 5 =ix, the acid is prepared by DCC or EDC condensation of the acyl-protected amino indole from viii with one of the acids in that group, followed by acyl deprotection. For R 5 =x, the acid compound wherein X 6 =H was first prepared by R. J. S. Beer, K. Clarke, H. F. Davenport and A. Robertson [J. Chem. Soc., 2029 (1951)]. By analogy with the acids for R 5 =viii, nitration will give the 5- N O 2 derivative, which can be converted to the other nitrogen functional groups defined for X6 as described above.
Wherein R 5 =xi represents the phosphodiesterase inhibitors, PDE-I and PDE-II, synthesized by N, Komoto, Y. Enomoto, M. Miyagaki, Y. Tanaka, K. Nitanai and H. Umezawa [Agric. Biol. Chem., 43, 555-557 and 550-561 (1979)]. The remaining structures in this category are intermediates in an alternate synthesis of PDE-I and II. The thiomethyl compound is prepared by the Gassman reaction [P. G. Gassman, G. Gruetzmacher and T. J. Van Bergen, J. Amer. Chem. Soc., 96, 5512-5517 (1974)] between the ester of the anilinoindole-2-carboxylate described for R 5 =x and the chlorosulfonium salt of α-thiomethyl acetaldehyde (as its acetal), with cyclization to the indole occurring after deacetalization. Raney nickel removes the thiomethyl group to yield the indole shown. Selective reduction by borane in acidic media [B. E. Maryanoff and D. F. McComsey, J. Org. Chem., 43, 2733-2735 (1978)] provides an alternate route to PDE-I and PED-II.
For R 5 =xii, the process used for ix is repeated on the more highly oxygenated indole derivatives listed in x, i.e., condensation of the acyl protected aniline with another indole-2-carboxylic acid derivative. The N-methyl compounds are made by reaction of the amides with CH 3 I and K 2 CO 3 in DMF. The phenolic groups are sterically hindered and not readily alkylated. The acid used to prepare R 5 =xiii has been synthesized by L. Grehn and U. Ragnarsson [J. Org. Chem., 46, 3492-3497 (1981)]. For R 5 =xiv, the corresponding acids were prepared by T. T. Sakai, J. M. Rio, T. E. Booth and J. D. Glickson [J. Med. Chem., 24, 279-285 (1981)]. For R 5 =xv, an excess of the appropriate commercially available ethylene glycol, polyethylene glyol, ethylene amine, or polyethylene amine is reacted with succinic anhydride or maleic anhydride to give the mono adduct carboxylic acids which can be used as the HCl or quaternary ammonium (CH 3 I) salt when X=N. Dimers of 3 and ultimately of 6 can be formed where R 5 =v, from commercially available dicarboxylic alkanes, or where R 5 =xvi, preparing the requisite acids by reaction of the appropriate ethylene glycol or amine, or di, tri, or tetramer thereof, with excess succinic or maleic anhydride to afford the bis adduct dicarboxylic acid.
The acids used to prepare compounds where R 5 is xvii are known in the art or are obtained from the esters which are known in the art or can be prepared by generally known procedures. For example, the following acids and esters are known: 1H-benzimidazole-2-carboxylic acid (H. C. Ooi, H. Suschitzky, J. Chem. Soc. Perkin Trans. 1, 2871 (1982)]; 2-benzoxazolecarboxylic acid (H. Moeller, Justic Liebigs Ann. Chem., 749, 1 (1971)); 2-benzothiazolecarboxylic acid, ethyl ester (A. McKillop et al., Tetrahedron Letters 23, 3357 (1982)) andfree acid (C. A. Reg. No. 3622-04-6); 2-benzofurancarboxylic acid (P. Bubin et al., Tetrahedron 37, 1131 (1981)); 5-amino-1H-indole-2-carboxylic acid, ethyl ester (C. A. Reg. No. 71086-99-2); 5-hydroxy-1H-indole-2-carboxylic acid (C. A. Reg. No. 21598-06-1); 5-hydroxybenzo[b]thiophene-2-carboxylic acid, methyl ester (C. A. Reg. No. 82788-15-6); 5-amino-benzo[ b]thiophene-2-carboxylic acid (C. A. Reg. No. 20699-85-8). For xviii the acid 1H-indene-2-carboxylic acid is known in the art (J. Vebrel and R. Carrie, Bull. Soc. Chim. Fr. 116 (1982)) and corresponding substituted acids are obtained by procedures known in the art. When R 5 is xix the compounds are prepared using acids which are commercially available, e.g., 2-pyridinecarboxylic acid and piperazinecarboxylic acid or are otherwise known, e.g., 5-hydroxy-2-pyridinecarboxylic acid (C. A. Reg. No. 15069-92-8), 5-amino-2-pyridinecarboxylic acid (C. A. Reg. No. 24242-20-4) and 5-mercapto-2-pyridinecarboxylic acid (C. A. Reg. No. 24242-22-6). For R 5 =xx, 2-naphthalenecarboxylic acid is commecially available, 6-hydroxy-2-naphthalenecarboxylic acid (C. A. Reg. No. 16712-64-4) and 6-amino-2-naphthalinecarboxylic acid, methyl ester (C. A. Reg. No. 5159-59-1) are known in the art and other suitable acids are prepared by general procedures known in the art. For R 5 =xxi, quinaldic acid and 2-quinoxalinecarbonyl chloride are commercially available, 6-aminoquinaldic acid, methyl ester (C. A. Reg. No. 16606-1G-104) is known in the art and other suitably substituted acids are prepared by procedures generally known in the art. For R 5 =xxii, the appropriate acids can be prepare as generally described by L. Grehn and U. Ragnarssson, J. Org. Chem. 46, 3492-3497 (1981).
Step 3: The sulfonylation chemistry described herein is the case of X=SO 2 CH 3 . The mesylate (or, for example, tosylate) can be prepared under conditions known in the art employing pyridine (with or without a catalyst such as dimethylaminopyridine), or other acid acceptors such as trialkylamines (with solvent) and the corresponding sulfonyl chloride. The halogen analogs of 4 could be prepared under standard procedures known in the art such as Ph 3 P/CCl 4 , or (CBr 4 ) or CI 4 .
Step 4: The O-deprotection step is described in detail for R1=CH 2 Ph in the following experiment. When R 5 =acyl, however, it is usually more convenient to employ benzyl deprotection with in situ generated trimethylsilyl iodide in refluxing acetonitrile [G. A. Olah, S. C. Narang, B. G. B. Gupta and R. Malhotra, J. Org. Chem., 44, 1247 (1979)] than the conventional hydrogenation over palladium procedure known in the art. Analogs insoluble in acetonitrile may be reacted in mixed acetonitrile/benzonitrile at 60°-80° C.
O-Deprotection of other R 1 groups can be done by a number of procedures described in the art involving methyl ether cleavage, only alkyl mercaptide in hexamethylphosphorictriamide (HMPA) under an inert atmosphere (95°-110° C.) have been found to be effective [S. C. Welch and A. S. C. P. Rao, Tet. Letters, 505 (1977) and T. R. Kelly, H. M. Dali and W-G. Tsang, Tet. Letters, 3859 (1977), or Me 2 S.BBr 3 in dichloroethane (P. G. Willard and C. B. Fryhle, Tet. Letters, 3731 (1980)].
Step 5: For R 5 =acyl this cyclization step is readily reversed during standard workup or chromatography on silica gel. Consequently the intermediate 5, when R 5 =acyl, are readily isolable under mildly acidic conditions. Isolation of the cyclopropa- products 6 is done in the presence of excess anhydrous bases, such as triethylamine. In contrast, the R 5 =sulfonyl analogs 6 are relatively more stable to acidic conditions.
Step 6: Treatment of the cyclopropa- product 6, when R 5 =acyl, with dilute aqueous base (0.1N NaOH or CH 3 NH 2 ) readily saponifies the imide linkage to give the N-deprotected vinylogous amide 7 (within Formula I) as its conjugate anion. The novelty of this particular step is that the cyclopropyl ring of 7 is relatively stable under these conditions, unlike that of spiro(2,5)octa-1,4-diene-3-one [R. Baird and S. Winstein, J. Amer. Chem. Soc., 85, 567 (1963)].
Step 7: (see Chart III) The alcohol function of the starting material 1 can be condensed, under conditions standard in the art, with the optically active, amino-protected amino acid, N-t-butoxy-carbonyl-L-tryptophan (commercially available), using a condensing agent such as ethyldimethylaminopropyl carbodiimide or dicyclohexyl-carbodiimide, with a catalytic amount of 4-dimethylaminopyridine in methylene chloride or other appropriate solvent. This affords a mixture of the shown ester diastereomers (Chart III), from which one diastereomer can be crystallized and separated from the other diastereomer using common organic solvents such as tetrahydrofuran and hexane.
Step 8: Hydrolysis of the purified separated diastereomer of the tryptophane ester to the optically active alcohol 1 is achieved by conditions standard in the art (aqueous sodium hydroxide, methanol and tetrahydrofuran, ambient temperature, one hour). The optically active alcohol 1 may then be carried through the above described steps 1-5 to afford optically active analogs in exactly the manner described above for the racemic compounds.
Structures for exemplary starting and end product compounds, illustrating the above Chart II and Chart II process steps as set forth for each of detailed examples which follow in Chart I.
EXAMPLE 1
Step 1-N-Deprotection
To 200 mg. (0.52 mmol) of the N-mesyl indolinoindole, i.e., 1,2,3,6-tetrahydro-8-(methyl)-3-(methylsulfonyl)-5-(phenylmethoxy)-[1,2-b:4,3-b']dipyrrole-1-methanol, in 10 ml. of dry THF and 10 ml. of toluene under N 2 was added, dropwise, 1.0 ml. (3.4 mmol) of 3.4M sodium bismethoxyethoxyaluminum hydride in toluene. The clear, colorless solution was quickly heated, and the condenser was lifted under a flow of nitrogen to allow the THF to escape. After the internal temperature of the solution reached 85° (15 min.) the condenser was replaced and heating was continued for 15 min. The yellow solution was cooled, quenched with 10 ml. of 15% K 2 CO 3 , and diluted with ether and water. The colorless ether phase was separated, dried (Na 2 SO 4 ) and stripped to 150 mg. of a nearly white foam, about 85% pure, of 1,2,3,6-tetrahydro-8-(methyl)-5-(phenylmethoxy)[1,2-b:4,3-b']dipyrrole-1-methanol by NMR. If CH.sub. 2 Cl 2 is used in the workup, the yield is substantially lower and the product is less pure.
NMR (CDCl 3 : 8.33 (brs, 1H), 7.4 (m, 5H); 6.8 (brs. 1H); 6.23 (s, 1H); 5.02 (s, 2H); 3.8-3.5 (m, 5H); 2.92 (brs. 2H, OH, NH); 2.32 (s, 3H).
EXAMPLE 2
Step 2-N-amidation
The reaction described in Step 1 was carried out on 100 mg. (0.25 mmol) of the N-mesyl indolinoindole, except that CH 2 Cl 2 was used instead of ether in the workup. The organic phase from that reaction which contains indolinoindole, i.e., 1,2,3,6-tetrahydro-8-(methyl)-5-(phenylmethoxy)[1,2-b:4,3-b']dipyrrole-1-methanol, was dried (Na 2 SO 4 ) and treated with 120 μl (1.2 mmol) of acetic anhydride. After 15 minutes the solution was concentrated and chromatographed on silica gel, eluting with 60% acetone/cyclohexane, to afford 52 mg. (0.148 mmol, 57%) of a white powder.
NMR (acetone-d 6 ): 10.17 (brs, 1H); 8.12 (s, 1H; 7.7-7.3 (m, 5H); 7.12 (m, 1H); 5.2 (s, 2H); 4.4-3.2 (m, 5H); 2.9 (brs, 1H, OH); 2.4 (s, 3H); 2.18 (s, 3H).
EXAMPLE 3
Step 2-N-Amidation
To 100 mg. (0.32 mmol) of indolinoinidole in 7 ml. of DMF under N 2 were added 55 mg. (0.34 mmol) of indole-2-carboxylic acid and 65 mg. (0.34 mmol) of ethyldimethylaminopropyl carbodiimde (EDC). The mixture was stirred at 25° C. for 22 hours. It was quenched with 1M KHSO 4 and extracted twice with ethyl acetate. The organic phase was washed with water and brine and dried (Na 2 SO 4 ). It was concentrated to 150 mg. (quantitative crude yield) of a yellow solid. A small amount precipitated from methylene chloride as a white solid on standing in the cold.
NMR (CDCl 3 : 10.25 (brs. 1H); 8.5 (brs, 1H); (s, 1H); 7.73-6.95 (m, 11H); 5.16 (s, 2H); 4.86-4.35 (m, 2H); 3.95-3.55 (m, 3H); 2.38 (s, 3H).
M.S. (E.I.): m/e 451 (M + ), 420, 360, 308, 277 (base peak), 144.
EXAMPLE 4
Step 2-N-Amidation
The reaction described in Step 1 was carried out on 127 mg. (0.33 mmol) of the N-mesyl indolinoindole, except that CH 2 Cl 2 was used instead of ether in the workup. The organic phase from that reaction was dried (Na 2 SO 4 ) and reacted with 38 μl (0.33 mmol) of benzoyl chloride and 46 μl (0.33 mmol) of triethylamine. After stirring for 30 minutes the reaction mixture was concentrated and chromatographed on silica gel, eluting with 40% acetone in cyclohexane. This afforded 61 mg. (0.15 mmol, 45% for two steps) of a nearly white powder.
NMR (CDCl 3 ): 8.5 (brs, 1H); 7.7-7.3 (m, 11H); 6.95 (brs, 1H); 5.17 [vbr (paramagnetic impurity), 2H]; 4.2-3.6 (brm, 5H); 2.38 (s, 3H).
EXAMPLE 5
Step 2-N-Amidation
To 70 mg. (0.23 mmol) of the indolinoindole in 5 ml. of DMF under N 2 were added 64 mg. (0.22 mmol) of 6-benzyloxy-7-methoxy indole-2-carboxylic acid and 45 mg. (0.24 mmol) of EDC. The mixture was stirred at 25° C. for three days. It was quenched with 1M KHSO 4 and extracted twice with ethyl acetate. The organic phase was washed with water and brine, dried (NaSO 4 ), and concentrated to 105 mg. of greenish oil. The NMR showed the desired product along with ˜10% by weight of DMF, for a yield of ˜70%.
NMR (acetone-d 6 ): 10.65 (brs, 1H); 10.2 (brs, 1H); 8.13 (s, 1H); 7.65-7.3 (m, 11HO; 7.1-6.95 (m, 3H); 5.2 (brs, 4H); 4.9-3.4 (m, ˜5H); 2.4 (s, 3H).
M.S. (E.I.): m/e 587 (M 30 ), 556, 496, 308, 280, 277 (base peak).
EXAMPLE 6
Step 2-N-Amidation
To 90 mg (0.29 mmol) of the indolinoindole in 6 ml of DMF under N 2 were added 60 mg (0.31 mmol) of 5-methoxyindole-2-carboxylic acid and 60 mg (0.31 mmol) of EDC. The reaction was stirred at 25° C. for 16 hrs. It was quenched with 1M KHSO 4 and extracted twice with ethyl acetate. The organic phase was washed with water and brine and dried (Na 2 S 4 ). It was concentrated in vacuo and chromatographed on silica gel, eluting with 10% acetone in methylene chloride. The product-containing fractions also contained DMF, and were diluted with methylene chloride, washed with water, dried (Na 2 SO 4 ) and concentrated to 93 mg (0.19 mmol, 66%) of yellow solid.
NMR (CDCl 3 ): 10.2 (brs, 1H); 8.5 (brs, 1H); 8.05 (s, 1H); 7.3 (brs, 5H); 7.2-6.8 (m, 5H); 5.02 (s, 2H); 4.8-3.3 (m, 5H); 3.75 (s, 3H); 2.6 (brs, 1H, OH); 2.28 (brs, 3H).
M.S. (E.I.): m/e 481 (M + ), 450, 390, 308, 277 (base peak), 174, 146.
EXAMPLE 7
Step 2-N-Amidation
To 90 mg (0.29 mmol) of the indolinoindole in 7 ml of DMF under N 2 were added 95 mg (0.30 mmol) of 5-(indol-2-ylcarbonylamino)-indole-2-carboxylic acid and 68 mg (0.34 mmol) of EDC. The reaction was stirred at 25° for 3 days. It was quenched with 1M KHSO 4 and extracted twice with ethyl acetate. The organic phase was washed with water and brine, dried (Na 2 SO 4 ), and stripped to 186 mg of a dark, granular solid. This was dissolved in a small amount of pyridine. Dilution with methylene chloride precipitated a light yellow, flocculent solid (130 mg, 0.21 mmol, 72%).
NMR (DMSO-d 6 ) (broadened spectrum): 11.8 (brs, 2H); 10.95 (brs, 1H); 10.3 (brs, 1H); 8.3 (brs, 1H); 8.0-7.1 (m, ˜15H); 5.3 (brs, 2H); 5.1 (vbr, ˜1H); 4.7 (vbr, ˜2H); 3.7 (vbr, ˜2H); 2.4 (brs, ˜3H).
M.S. (E.I.): 609 (M + ), 593, 577, 465, 444, 319, 290, 276, 275, 176, 158, 144, 132 (base peak).
(FAB, glycerol): 610 (M+H + ), 302, 287, 186, 144.
EXAMPLE 8
Step 2-N-Amidation
To 100 mg (0.32 mmol) of the indolinoindole in 7 ml of DMF under N 2 were added 90 mg (0.32 mmol) of 5-benzoylamino-indole-2-carboxylic acid and 65 mg (0.34 mmol) of EDC. The reaction was stirred at 25° for 3 days. It was quenched with 1M KHSO 4 and extracted twice with ethyl acetate. The opaque organic phase was washed with water and brine, dried (Na 2 SO 4 ), and concentrated.
NMR (pyridine-d 6 ): 12.0 (brs, 1H); 10.9 (brs, 1H); 8.83 (s, 1H); 8.62 (s, 1H); 8.45-8.32 (d of d, 2H); 8-7.75 (m, 2H); 7.53-7.3 (m, ˜11H); 5.3 (brs, 3H); 4.85 (vbr, ˜1H); 4.4-3.9 (m, ˜3H); 2.54 (s, ˜3H).
EXAMPLE 9
Step 2-N-Amidation
To 48 mg (0.155 mmol) of the indolinoindole in 6 ml of DMF under N 2 were added 68 mg (0.155 mmol) of the 5-amido substituted indole-2-carboxylic acid and 31 mg (0.155 mmol) of EDC. The reaction was stirred at 25° for 2 days. It was quenched with 1M KHSO 4 and extracted twice with ethyl acetate. The opaque organic phase was washed with water and brine, dried (Na 2 SO 4 ), and concentrated to 105 mg (0.144 mmol, 93%) of a light brown solid.
NMR (pyridine-d 6 ): 13.3 (vbr, ˜1H); 12.8 (brs, 1H); 12.05 (brs, 1H); 10.97 (s, 1H); 10.88 (s, 1H); 8.9 (s, 1H); 8.64 (s, 1H); 8.45-8.33 (d of d, 2H); 8-7.75 (m, ˜5H); 7.55-7.3 (m, ˜11H); 5.28 (brs, ˜3H); 4.75-3.8 (vbr, ˜4H); 2.5 (s, ˜3H).
EXAMPLE 10
Step 2-N-Amidation
To 100 mg (0.32 mmol) of the indolinoindole in 7 ml of DMF under N 2 were added 70 mg (0.22 mmod) os 5-ureido-indole-2-carboxylic acid and 65 mg (0.34 mmol) of EDC. The reaction was stirred at 25° for 4 days. It was quenched with 1M KHSO 4 and extracted twice with ethyl acetate. The organic phase was washed with water and brine, dried (Na 2 SO 4 ) and concentrated to 140 mg (0.27 mmol, 86%) of a green-tainted white solid.
NMR (pyridine-d 5 ): 12.75 (brs, 1H); 12.1 (brs, 1H); 9.65 (s, 1H); 8.65 (s, 1H); 8.53 (s, 1H); 7.75-7.2 (m, 9H); 6.65 (brs, 2H); 5.28 (s, 2H); 4.85-3.85 (brm, ˜5H); 2.55 (s, 3H).
EXAMPLE 11
Step 2-N-Amidation
To 71 mg (0.23 mmol) of the indolinoindole in 5 ml of DMF under N 2 were added 88 mg (0.23 mmol) of the ureido-bis indolic acid and 45 mg (0.23 mmol) of EDC. The reaction was stirred at 25° for 2 days. It was quenched with 1M KHSO 4 and extracted twice with ethyl acetate. The organic phase was washed with brine. A brown emulsive layer was diluted with acetone, filtered, and the filtrate combined with the organic phase and dried (Na 2 SO 4 ). It was concentrated in vacuo to 135 mg (0.20 mmol, 88% crude yield) of a greenish-grey solid.
NMR (pyridine-d 5 ): 13.25 (brs, 1H); 13.0 (brs, 1H); 12.2 (brs, 1H); 11.16 (brs, 1H); 9.8 (brs, 1H); 8.9 (s, 1H); 8.62 (s, 1H); 8.5 (s, 1H); 8.2-7.35 (m, 12H); 5.28 (brs, ˜3H); 4.8-3.8 (brm, ˜4H); 2.55 (s, ˜3H).
EXAMPLE 12
Step 2-N-Amidation
A 60 mg (0.19 mmol) quantity indolinoindole was dissolved with stirring under N 2 at RT in 4 ml DMF. Added 38 mg (0.22 mmol) quinaldic acid and 40 mg (0.20 mmol) EDC. Left to react for 22 hrs, when the reaction mixture was diluted with CH 2 Cl 2 . The solution was washed with 5% NaHSO 4 , 5% NaHCO 3 and brine, backextracting with CH 2 Cl 2 . The organic phases were dried over Na 2 SO 4 and evaporated, leaving a brown oil.
The crude product was chromatographed over 100 g silica gel, eluting with a gradient of 50% EtOAc-50% hexane to 80% EtOAc-20% hexane. Fractions of 20 ml were collected, analyzing them by TLC. Fractions 32-42 contained the major product and were combined and evaporated, leaving 80 mg (91% yield) yellow solid.
______________________________________TLC: Silica gel; UV visualization.______________________________________50% acetone-50% CH.sub.2 Cl.sub.2 50% EtOAc-50% hexaneR.sub.f = 0.92 R.sub.f = 0.39______________________________________
NMR: (CDCl 3 , TMS, δ); 2.2 (s, 3H); 2.1-2.5 (broad, 1H); 3.4-3.8 (m, 3H); 4.2-4.7 (m, 2H); 5.1 (s, 2H); 6.8 (broad, 1H); 7.2-8.2 (m, 12H); 8.4 (broad, 1H).
EXAMPLE 13
Step 2-N-Amidation
A 0.26 mmol quantity indolinoindole was stirred at RT under N 2 in 5 ml dry DMF. Added 32 mg (0.29 mmol) pyrrole-2-carboxylic acid and 52 mg (0.26 mmol) EDC. Left to react for 23 hrs, when the reaction mixture was diluted with CH 2 Cl 2 and washed with 5% NaHSO 4 , 5% NaHCO 3 and brine, backextracting with CH 2 Cl 2 . The organic phases were dried over Na 2 SO 4 and evaporated under vacuum.
The crude product was chromatographed over 15 g silica gel, eluting with 250 ml 50% EtOAc-50% hexane, followed by 100 ml 60% EtOAc-40% hexane. Fractions of 5 ml were collected, analyzing them by TLC. Fraction 14-40 contained the product spot and were combined and evaporated, leaving 76 mg (73% yield) solid.
TLC: Silica gel; UV visualization; 50% EtOAc-50% hexane; R f : 0.31.
NMR: (CDCl 3 , d 4 -MeOH; TMS, δ); 2.4 (s, 3H); 2.7-3.0 (m, 2H); 3.4-4.8 (m, 5H); 5.2 (s, 2H); 6.3 (broad, 1H); 6.8 (broad, 1H); 6.95 (broad, 1H); 7.3-7.6 (m, 5H); 8.0 (s, 1H); 10.2 (broad, 1H).
EXAMPLE 14
Step 3-O-Sulfonylation
The crude product from the reaction of 1 mmol of the indolino-indole with acetic anhydride (Step 2) was dissolved in 4 ml of distilled (NaOH) pyridine and ˜10 mg of recrystallized dimethylaminopyridine (DMAP) was added. The solution was purged with N 2 , and 250 μl (3.2 mmol) of methanesulfonyl chloride (MsCl) was added. After 20 min of stirring at 25°, the reaction was quenched with 10% HCl and extracted with ethyl acetate. The organic phase was dried (Na 2 SO 4 ) and treated with decolorizing charcoal for 2 hr. Filtration afforded a yellow solution containing two components. The main component was the desired mesylate. The minor product was the acetate ester. This was saponified (NaOH, EtOH/H 2 O, 10 min) and mesylated as above. The total yield of product was 242 mg (57%).
NMR (DMSO-d 6 ): 11.0 (brs, 1H); 7.97 (s, 1H); 7.6-7.4 (m, 5H); 7.18 (s, 1H); 5.27 (s, 2H); 4.5-4.0 (m, 5H); 3.16 (s, 3H); 2.38 (s, 3H); 2.2 (s, 3H).
EXAMPLE 15
Step 3-O-Sulfonylation
To 150 mg (0.32 mmol) of the alcohol substrate in 3 ml of methylene chloride and 3 ml of dry pyridine under N 2 were added ˜5 mg of DMAP and 100 μl (1.3 mmol) of MsCl. After 10-15 min of stirring at 25°, the reaction was quenched with 10% HCl and extracted with ethyl acetate. The organic phase was washed with more 10% HCl, then brine, and dried (Na 2 SO 4 ). It was concentrated to 158 mg (0.3 mmol, 93%) of grey-blue solid.
NMR (acetone-d 6 ): 10.9 (brs, 1H); 10.4 (brs, 1H); 8.1 (s, 1H); 7.8-7.1 (m, 11H); 5.25 (s, 2H); 4.8-4.13 (m, 5H); 2.97 (s, 3H); 2.47 (s, 3H).
EXAMPLE 16
Step 3-O-Sulfonylation
To 61 mg (0.15 mmol) of the alcohol substrate in 1 ml of dry pyridine under N 2 was added 25 μl (0.32 mmol) of MsCl. After stirring for 2 hr at 25°, the reaction was quenched with 10% HCl and extracted with CH 2 Cl 2 . The organic phase was dried (Na 2 SO 4 ) and concentrated to 77 mg (quantitative crude yield) of an impure, foamy solid.
NMR (acetone-d 6 ): 10.3 (brs, 1H); 7.7-7.3 (m, 11H); 7.14 (brs, 1H); 5.1 [brs (paramagnetic impurity), 2H]; 4.55-4.0 (m, 5H); 2.92 (s, 3H); 2.4 (s, 3H).
EXAMPLE 17
Step 3-O-Sulfonylation
To 58 mg (0.1 mmol) of the alcohol substrate in 1 ml of methylene chloride and 1 ml of dry pyridine under N 2 were added ˜5 mg of DMAP and 50 μl (0.65 mmol) of MsCl. After 25 min of stirring at 25°, the reaction was quenched with 10% HCl and extracted with ethyl acetate. The organic phase was washed with more 10% HCl, then brine, dried (Na 2 SO 4 ), and stripped to 73 mg (quantitative crude yield) of a semicrystalline film.
NMR (acetone-d 6 +MeOH-d 4 ): 7.87 (brs, 1H); 7.55-7.3 (m, 11H); 7.1-6.93 (m, 3H); 5.19 (s, 2H); 5.15 (s, 2H); 4.7-4 (m, 5H); 3.98 (s, 3H); 2.87 (s, 3H); 2.4 (s, 3H). (Not examined beyond δ 10.5).
EXAMPLE 18
Step 3-O-Sulfonylation
To 88 mg (0.18 mmol) of the alcohol substrate in 2 ml of methylene chloride and 2 ml of dry pyridine under N 2 were added ˜4 mg of DMAP and 55 μl (0.71 mmol) of MsCl. After 15 min of stirring at 25°, the reaction was quenched with 10% HCl and extracted with ethyl acetate. The organic phase was washed with 10% HCl and brine and dried (Na 2 SO 4 ). The initially almost colorless solution became a dark blue-grey upon concentration in vacuo, affording 112 mg (quantitative crude yield) of blue-grey solid.
NMR (acetone-d 6 ): 10.3 (brs, 1H); 8.1 (s, 1H); 7.56-7.1 (m, 9H); 7.02-6.88 (d of d, 1H); 5.17 (s, 2H); 4.8-4 (m, ˜5H); 3.97 (s, ˜3H); 2.95 (s, 3H); 2.45 (s, 3H). (Not examined beyond δ 10.5).
EXAMPLE 19
Step 3-O-Sulfonylation
To 120 mg (0.2 mmol) of the alcohol substrate in 5 ml of dry pyridine under N 2 were added ˜5 mg of DMAP and 75 μl (1 mmol) of MsCl. After 10 min of stirring at 25°, the mixture was concentrated in vacuo, quenched with 10% HCl, and extracted twice with ethyl acetate. The organic phase was washed with brine, dried (Na 2 SO 4 ) and stripped to 123 mg (0.18 mmol, 90% crude yield).
NMR (acetone d 6 ): 11.1 (vbr, ˜1H); 10.3 (brs, ˜1H); 9.8 (s, 1H); 8.43 (s, 1H); 8.1 (s, 1H); 7.76-7.14 (m, ˜15H); 5.21 (s, 2H); 4.8-4.1 (brm, ˜5H); 2.94 (s, 3H); 2.41 (s, 3H).
EXAMPLE 20
Step 3-O-Sulfonylation
The crude product obtained from the EDC coupling (Step 2) of 0.32 mmol of the indolinoindole and an equivalent of 5-benzoylamino-indole-2-carboxylic acid was dissolved in 5 ml of dry pyridine under N 2 . To this were added ˜5 mg of DMAP and 150 μl (2 mmol) of MsCl. After 50 min of stirring at 25°, the reaction was quenched with 10% HCl and extracted twice with ethyl acetate. The organic phase was washed with water and brine, dried (Na 2 SO 4 ), and concentrated to 160 mg (0.25 mmol, 77% crude yield for two steps) of green-tainted solid.
NMR (acetone-d 6 ): 11.0 (brs, 1H); 10.3 (brs, 1H); 9.6 (s, 1H); 8.4 (s, 1); 8.1 (m, 3H); 7.65-7.3 (m, 10H); 7.15 (brs, 2H); 5.16 (s, 2H); 4.8-4.0 (m, ˜5H); 2.92 (s, 3H); 2.4 (brs, 3H).
EXAMPLE 21
Step 3-O-Sulfonylation
To 105 mg (0.14 mmol) of the alcoholic substrate in 5 ml of dry pyridine under N 2 were added ˜5 mg of DMAP and 100 μl (1.3 mmol) of MsCl. After 3 hr of stirring at 25°, the reaction was quenched with 10% HCl and extracted twice with ethyl acetate. The organic phase was washed with water and brine, dried (Na 2 SO 4 ) and concentrated to 102 mg (0.13 mmol, 88% crude yield) of a dark solid.
NMR (acetone-d 6 ): 11.3 (brs, 1H); 11.15 (brs, 1H); 10.3 (brs, 1H); 9.73 (s, 1H); 9.55 (s, 1H); 8.43 (s, 1H); 8.31 (s, 1H); 8.1 (m, 3H); 7.65-7.3 (m, 13H); 7.1 (brs, 2H); 5.12 (s, 2H); 4.8-4 (m, ˜5H); 2.9 (s, 3H); 2.35 (brs, 3H).
EXAMPLE 22
Step 3-O-Sulfonylation
To 140 mg (0.27 mmol) of the alcohol substrate in 5 ml of dry pyridine under N 2 were added ˜5 mg of DMAP and 150 μl (2 mmol) of MsCl. After 3 hr of stirring at 25°, the reaction was quenched with 10% HCl and extracted twice with ethyl acetate. The organic phase was washed with water and brine and dried (Na 2 SO 4 ). The product was concentrated and chromatographed on silica gel, eluting with 50% acetone in cyclohexane. The first eluted product (R f =0.35 in 50% acetone/cyclohexane) was the cyanamide (63 mg, 0.11 mmol, 41%).
NMR (acetone-d 6 ): 11.0 (brs, 1H); 10.3 (brs, 1H); 8.64 (s, 1H); 8.1 (s, 1H); 7.68-7.3 (m, 7H); 7.2-7.03 (m, 3H); 5.22 (s, 2H); 4.85-3.9 (m, ˜5H); 2.95 (s, 3H); 2.45 (s, 3H).
M.S. (F.A.B., glycerol+thioglycerol): 588 (M+H 2 O+H + ); 570 (M+H + ), 510, 492, 474, 199, 187, 102, 91.
The second eluted product was the ureido compound (34 mg, 0.058 mmol, 21%).
NMR (pyridine-d 5 ): 12.8 (brs, 1H); 12.25 (brs, 1H); 9.55 (s, 1H); 8.52 (s, 2H); 7.8-7.2 (m, 9H); 6.57 (brs, 2H); 5.26 (s, 2H); 4.95-4.3 (m, 5H); 3.08 (s, 3H); 2.55 (s, 3H).
M.S. (F.A.B., glycerol+thioglycerol): 588 (M+H + ); 510, 492, 126, 91.
EXAMPLE 23
Step 3-O-Sulfonylation
To 135 mg (0.20 mmol) of the alcohol substrate in 4 ml of dry pyridine under N 2 were added ˜5 mg of DMAP and 150 μl (2 mmol) of MsCl. After stirring for 1 hr at 25°, the reaction was quenched with 10% HCl and extracted twice with ethyl acetate. The organic phase was washed with more 10% HCl and with brine and dried (Na 2 SO 4 ). The organic phase was concentrated to ˜15 ml, and ˜0.3 ml of concentrated sulfuric acid was added with stirring (to hydrolyze the cyanamide to the urea). After ˜1 min the yellow-brown solution was diluted with ethyl acetate and washed with water. The aqueous phase was re-extracted with ethyl acetate, and the combined organic phases were washed with brine and dried (Na 2 SO 4 ). Concentration and chromatography on silica gel with 50% acetone in methylene chloride afforded 39 mg (0.052 mmol, 26% of a faintly yellow crystalline solid).
NMR (pyridine-d 5 ): 13.1 (brs, ˜1H); 12.98 (brs, ˜1H); 12.28 (brs, 1H); 10.9 (s, 1H); 9.5 (s, 1H); 8.82 (1H, shoulder on pyridine signal); 8.53 (s, 1H); 8.47 (s, 1H); 8.0 (m, 1H); 7.77-7.3 (m, 11H); 6.55 (brs, 2H); 5.27 (s, 2H); 5-4.3 (m, ˜5H); 3.13 (s, 3H); 2.55 (s, 3H).
EXAMPLE 24
Step 3-O-Sulfonylation
A 241 mg quantity (0.52 mmol) alcohol was dissolved with stirring at RT under N 2 in 5 ml dry pyridine. Syringed in 210 ml (excess) mesyl chloride and left to react for 6 hours. Added a few drops of 5% NaHSO 4 and then partitioned between CH 2 Cl 2 -5% NaHSO 4 . The layers were separated and the organic phase dried over Na 2 SO 4 and evaporated, leaving 286 mg brown solid (100% yield).
TLC: Silica gel; UV visualization; 50% EtOAc-50% hexane; R f : 0.65.
NMR: (CDCl 3 , TMS, δ): 2.4 (s, 3H); 2.8 (s, 3H); 3.8-4.8 (m, 5H); 5.3 (s, 2H); 7.0 (broad, 1H); 7.2-8.6 (m, 13H).
EXAMPLE 25
Step 3-O-Sulfonylation
A 76 mg quantity (0.19 mmol) alcohol and 2 ml dry pyridine were stirred at RT under N 2 . Syringed in 70 μl (excess) mesyl chloride and left to react for 4 hours. Added a few drops of 5% NaHSO 4 and then partitioned the reaction mixture between CH 2 Cl 2 -5% NaHSO 4 . Separated the layers and dried the organic phase over Na 2 SO 4 , evaporating it under vacuum. This left 97 mg brown solid (100% crude yield).
TLC: Silica gel; UV visualization; 50% EtOAc-50% hexane; R f : 0.69.
NMR: (CDCl 3 , TMS, δ): 2.4 (s, 3H); 2.8 (s, 3H); 3.5-4.8 (m, 5H); 5.2 (s, 2H); 6.3 (broad, 1H); 6.75 (broad, 1H); 6.9 (broad, 2H); 7.2-7.9 (m, 4H); 8.0 (broad, 1H); 8.6 (broad, 1H); 10.2 (broad, 1H).
EXAMPLE 26
Step 4-O-Deprotection
The reaction described in Step 3 was carried out on 52 mg (0.148 mmol) of the N-acetyl indolinoindole to afford 63 mg of crude mesylate as a purple-tinted white solid. This was dissolved in 10 ml of DMF and slurried with 0.5 teaspoonful of activated Raney nickel in ethanol for 20 min. To the filtered solution was added 36 mg of Pd/C, and the mixture was shaken under H 2 for 50 min. The mixture was filtered through Celite, washing with DMF, and concentrated in vacuo. The crude product in DMF was treated with 70 μl of ethyldiisopropylamine for about 10 min (Step 5, in the expectation of forming the cyclopropylspirodienone) and rapidly chromatographed (50% acetone/cyclohexane eluant). Upon standing at 4° overnight, the product-containing fractions deposited white granular crystals (10 mg, 0.03 mmol, 20%) identified as the uncyclized phenol mesylate.
NMR (DMSO-d 6 ): 7.6 (s, 1H); 7.0 (s, 1H); 4.4-3.8 (m, 5H); 3.12 (s, 3H); 2.32 (s, 3H); 2.15(s, 3H).
MS: (E.I.): m/e [338 (M + ), not found]; 242 (M-HSO 3 Me), 228, 213, 200, 186, 96, 79.
EXAMPLE 27
Step 5-Cyclization-Cyclopropa[c]pyrrolo[3,2-e]indol-4(5H)-one, 2-acetyl-1,2,8,8a-tetrahydro-7-methyl-
The mother liquors from the fractions which had yielded the phenolic mesylate described in Step 4 (that reaction product had been briefly reacted with ethyldiisopropyl amine, vide infra) were recrhomatographed on silica gel, eluting with 50% acetone/cyclohexane, to afford 10 mg. of a powdery white solid identified as the cyclopropyl spirodienone (0.04 mmol, 30% from the N-acetyl alcohol).
NMR (DMSO-d 6 , 200 MHz, 70° C.): B 6.8. (s, 1H); 6.67 (s, 1H); 4.08 (dd, 1H, J c ,d ˜10 Hz); 4.02 (dd, 1H, J cd ˜10 Hz, J d ,e ˜fHz); 3.03 (m, 1H); 2.17 L (s, 3H); 1.96 (s, 3H); 1.89 (dd, 1H, J e ,f ˜8 Hz, J f ,g ˜4 Hz); 1.23 (dd, 1H, J e ,g ˜4 Hz, J f ,g ˜4H).
MS: (E.I.): m/e 242 (M + ); 200, 199, 185, 171, 156.
UV: (MeOH) λ max , 348 nm (E=14,000), 284 nm (E=18,100).
Following procedures described hereinabove, using stoichiometric equivalent amounts of the N-decanoylindolinoindole, N-hexadecanoylindolinoindole, and N-licosanoylindolinoindole, in place of the N-acetylindolinoindole in Example 26, and then cyclizing the product thereof as in Example 27 there can be formed the following analogous compounds, respectively:
1,2,8,8a-tetrahydro-7-methyl-2-decanoyl-cyclopropa[c]pyrrolo[3,2-e]endol-4(5H)-one,
1,2,8,8a-tetrahydro-7-methyl-2-hexadecanoylcyclopropa[c]pyrrolo[3,2,e]indol-one, and
1,2,8,8a-tetrahydro-7-methyl-2-eicosanoylcyclopropa[c]pyrrolo[3,2-e]indol-4(5H)-one.
EXAMPLE 28
Step 4-O-Deprotection; Step 5-Cyclization-Cyclopropa[c]-pyrrolo[3,2-e]indol-4(5H)-one, 1,2,8,8a-tetrahydro-2-[(1H)-indol-2-ylcarbonyl)]-7-methyl-
To 162 mg (0.30 mol) of the protected mesylate and 150 mg (1 mmol) of dry NaI in 6 ml of distilled (CaH 2 ) acetonitrile under N 2 was added 130 μl (1 mmol) of distilled trimethylsilyl chloride (TMS-Cl). The mixture was heated to reflux and stirred for 10 min. The reaction was cooled, diluted with ethyl acetate, and washed with 0.1M sodium thiosulfate. The organic phase was washed with water and brine and dried (Na 2 SO 4 ). Distilled triethylamine (200 μl) was added and the solution, after 15 min, was concentrated. DMF (100 μl) was added to dissolve the brown precipitate which formed, and another 100 μl of triethylamine was added. The mixture was chromatographed on silica gel, eluting with 50% acetone in cyclohexane containing 100 μl of triethylamine for every 100 ml of eluant. The product-containing fractions were concentrated to 49 mg of a light tan solid. This was dissolved in acetone and chilled. Two crops of cream colored precipitate were obtained, together weighing 17.2 mg (0.05 mmol, 17%). Rechromatography of the mother liquor gave 12 mg of impure product.
NMR (DMSO-d 6 ): 11.82 (brs, 1H); 11.55 (brs, 1H); 7.8-7.15 (m, 5H); 6.95 (m, 1H); 6.72 (s, 1H); 4.45 (m, 2H); 3.2 (m, 1H); 2.0 (brs, 4H); 1.38 (t, 1H, J≃4 Hz).
M.S. (E.I.): 343 (M + ), 326, 200, 199, 144.
UV: (1% DMF in MeOH) λ max 362 nm (ε=22,000), 310 nm (ε=22,000).
EXAMPLE 29
Step 4-O-Deprotection
To 77 mg (0.15 mmol) of the crude mesylate from Step 3 was added 5 ml of a slurry of activated Raney nickel in DMF. After 40 min the mixture was filtered, washing the catalyst with DMF. To this solution (˜35 ml) was added 53 mg of 10% Pd/C and the mixture was hydrogenated (14 psi) on a Parr apparatus for 3 hr. The mixture was then filtered, washing the catalyst with DMF, and the DMF was removed in vacuo. To the residue was added 10 ml of CH 2 Cl 2 . A dark solid precipitated. The mixture was treated with ethyl diisopropylamine (75 μl, 0.43 mmol) overnight at 4°; it remained largely heterogeneous however. It was chromatographed on silica gel, eluting with 30% acetone in cyclohexane, to afford 14 mg (0.035 mmol, 23%) of a white granular solid.
NMR (DMSO-d 6 ): 9.73 (s, 1H): 7.45 (m, 6H); 7.05 (s, 1H); 4.43-3.67 (m, 5H); 3.03 (s, 3H); 2.3 (s, 3H).
EXAMPLE 30
Step 5-Cyclization-Cyclopropa[c]pyrrolo[3,2-e]indol-4(5H)-one, 2-benzoyl-1,2,8,8a-tetrahydro-7-methyl-
To 13 mg (0.033 mmol) of the phenolic mesylate in 0.4 ml of DMSO-d 6 and ˜5 ml of CH 2 Cl 2 was added 50 μl (0.28 mmol) of ethyldiisopropylamine. After 30 min, the reaction was diluted with CH 2 Cl 2 , washed with water, and dried (Na 2 SO 4 ) and concentrated. The residue was stripped in vacuo from 50% acetone in cyclohexane to afford 7 mg of a white solid.
NMR (DMF-d 7 ): 7.6 (m, 5H); 6.98 (m, 1H); 5.85 (s, 1H); 4.3-3.8 (m, 2H); 3.05 (m, 1H); 2.03 (s, 3H); 2.0 (m, 1H); 1.6 (t, 1H, J=4 Hz).
UV: (MeOH) λ max 352 nm (E=14,600), 288 nm (E=14,900).
EXAMPLE 31
Step 4-O-Deprotection
To 66 mg (0.1 mmol) of the protected mesylate was added activated Raney nickel in 30 ml of DMF and 5 ml of ethanol. After 40 min, the mixture was filtered, washing the catalyst with DMF. The resulting yellow solution was hydrogenated on a Parr apparatus (19 psi) with 140 mg of Pd/C for 4 hr. The mixture was filtered and the solution concentrated to ˜3 ml. It was diluted with CH 2 Cl 2 , washed with water, dried (Na 2 SO 4 ), concentrated, and chromatographed, to afford 10 mg (26%) of a nearly white solid.
NMR (acetone-d 6 ): 10.3 (vbr, ˜1H); 10.0 (vbr, <1H); 9.85 (vbr, <1H); 7.88 (s, 1H); 7.4-6.8 (m, 4H); 4.73-4.1 (m, 5H); 3.97 (s, 3H); 3.0 (s, ˜3H); 2.45 (s, 3H).
EXAMPLE 32
Step 5-Cyclization-Cyclopropa[c]pyrrolo[3,2-e]indol-4(5H)-one, 1, 2,8,8a-tetrahydro-2-[(6-hydroxy-7-methoxy-1H-indol-2-yl)carbonyl]-
To 10 mg (0.026 mmol) of the uncyclized mesylate in ˜0.4 ml of DMSO-d 6 and 2 ml of CH 2 Cl 2 was added 60 μl of ethyldiisopropylamine. The reaction was concentrated in vacuo (to remove excess amine), diluted with CH 2 Cl 2 , and washed with water. The organic phase was dried (Na 2 SO 4 ) and concentrated, and the residue dissolved in ˜0.4 ml of acetone-d 6 for NMR analysis, which showed product as well as ammonium salt present. The product crystallized in the NMR tube, affording ˜5 mg of pure product.
NMR (DMSO-d 6 ): 11.5 (brs 1H); 11.3 (brs, 1H); 9.2 (s, 1H); 7.28 (d, 1H, J˜9 Hz); 7.11 (s, 1H); 6.94 (s, 1H); 6.79 (d, 1H, J˜9 Hz); 6.51 (s, 1H); 4.38 (m, 2H); 3.75 (s, ˜3H); 3.15 (m, 1H); 2.02 (s, 3H); 1.96 (m, 1H); 1.42 (m, 1H).
M.S. (E.I.): m/e 389 (M + ), 372, 281, 207, 201, 190, 147, 134.
F.A.B., glycerol: 392 (M + +H+H 2 ), 203, 202, 201, 190, 187.
UV: (0.5% DMF in MeOH) λ max 371 nm (ε=23,000), 322 nm (ε=15,000), 293 nm (ε=13,000).
EXAMPLE 33
Step 4-O-Deprotection; Step 5-Cyclization-Cyclopropa[c]pyrrolo[3,2-e]indol-4(5H)-one 1,2,8,8a-tetrahydro-2-[(5-methoxy-1H-indol-2-yl)carbonyl]-
Steps 2 and 3 were carried out on 90 mg (0.29 mmol) of the indolinoindole without isolation of the intermediates. The protected mesylate, in 30 ml of ethyl acetate, was treated with ˜10 cm 3 of activated Raney nickel in 100 ml of ethanol. After 30 min, the mixture was filtered and the filtrate was concentrated. The residue was diluted with ethyl acetate and washed with water, then brine, dried (Na 2 SO 4 ) and concentrated to ˜30 ml. To this was added 100 ml of ethanol and 140 mg of Pd/C and the mixture was hydrogenated on a Parr apparatus (17 psi) for 1 hr. No reaction occurred, so the suspension was again treated with Raney nickel, filtered, concentrated, dissolved in ethyl acetate, washed with water and brine, dried, concentrated, diluted with ethanol and hydrogenated for 45 min with 90 mg Pd/C. Reaction occurred. The mixture was filtered, concentrated, and dissolved in 2 ml of DMF. It was diluted with ˜5 ml of ethyl acetate and 200 μl of ethyldiisopropylamine was added. After 75 min, the mixture was diluted with ethyl acetate, washed with dilute NH 4 Cl and brine, dried (Na 2 SO 4 ) and concentrated. Chromatography on silica gel, eluting with 50% acetone in cyclohexane, afforded 11.6 mg (0.03 mmol, 11% for Steps 2-5) of a light yellow solid.
NMR (DMSO-d 6 ): 11.7 (brs, 1H); 11.55 (brs, 1H); 7.45 (d, 1H, J=9 Hz); 7.2-6.9 (m, 4H); 6.7 (s, 1H); 4.44 (m, 2H); 3.78 (s, 3H); 3.12 (m, 1H); 2.00 (s, 3H); 1.96 (m, 1H); 1.36 (t, 1H).
M.S.: Calc. for C 22 H 19 N 3 O 3 : 373.1426; found: 373.1404.
UV (1% DMF in MeOH): λ max 363 nm (ε=19,000), 311 nm (ε=17,000).
EXAMPLE 34
Step 4-O-Deprotection; Step 5-Cyclization-1,2,8,8a-tetrahydro-7-methyl-2-[[5-[[[1H-indol-2-yl]carbonyl]amino]-1H-indol-2-yl]carbonyl]cyclopropa[c]pyrrolo[3,2-e]indol-4(5H)-one
To 220 mg (0.32 mmol) of the protected mesylate and 190 mg (1.27 mmol) of dry sodium iodide under N 2 were added 6 ml of dry acetonitrile and 2 ml of dry benzonitrile. Trimethylsilylchloride (160 μl, 1.26 mmol) was then introduced and the mixture was heated to 65° for 45 min. Reaction was still incomplete, so 100 mg (0.67 mmol) of NaI and 80 μl (063 mmol) of TMS-Cl were added, and the mixture was heated to reflux for 15 min. The mixture was cooled, diluted with ethyl acetate, and washed with 0.1M sodium thiosulfate, then with brine, and dried (Na 2 SO 4 ). The solution was concentrated to an oil (benzonitrile). Addition of 100 μl of dry triethylamine afforded a semisolid, which was diluted with ethyl acetate and washed with water, dried (Na 2 SO 4 ) and concentrated. A small amount of DMF was added to dissolve the resulting suspension, and the oil was chromatographed on silica gel, eluting with 50% acetone in cyclohexane and gradually increasing the acetone content of the eluant. The purest fractions were combined and stripped to ˜50 mg of an off-white solid. This was dissolved in ˜3 ml of acetone and 20 μl of triethylamine was added. A light yellow solid precipitated (23.5 mg) and was washed and collected. The mother liquor and less pure chromatography fractions were combined and again dissolved in a small volume of acetone and 20 μl of triethylamine. A second crop of product precipitated and was washed and collected (24 mg; total yield 47.5 mg, 0.095 mmol, 30%). Both crops had the same extinction coefficients on UV analysis.
NMR (DMSO-d 6 ): 11.9 (brs, 1H); 11.8 (brs, 1H); 10.33 (s, 1H); 8.3 (s, 1H); 7.8-6.97 (m, 10H); 6.78 (s, 1H); 4.5 (m, 2H); 3.14 (m, 1H); 2.03 (s, 3H); 1.96 (m, 1H); 1.42 (m, 1H).
M.S. (F.A.B., glycerol): 504 (M+H+H 2 ), 302, 202, 201, 187, 172, 144.
UV (1% DMF in EtOH): λ max 363 nm (ε=28,500), 313 nm (ε=43,000).
EXAMPLE 35
Step 4-O-Deprotection; Step 5-Cyclization-1,2,8,8a-tetrahydro-7-methyl-[[5-benzoylamino-1H-indol-2-yl]carbonyl]cyclopropa[c]pyrrolo[3,2-e]indol-4(5H)-one
To 160 mg (0.25 mmol) of the protected mesylate and 150 mg (1 mmol) of dry NaI under N 2 were added 6 ml of dry acetonitrile and 130 μl (1 mmol) of TMS-Cl. The mixture was heated to reflux for 15 min, cooled, diluted with ethyl acetate, and washed with 0.1M sodium thiosulfate. The organic phase was washed with water and brine and dried (Na 2 SO 4 ). Triethylamine (400 μl) was added to the organic solution. After 30 min 200 μl of DMF was added and the solution was concentrated. The residue was chromatographed on silica gel, eluting with 50% acetone in cyclohexane containing 100 μl of triethylamine per 100 ml of eluant. The product-containing fractions were stripped, dissloved in 300 μl of acetone, and the light yellow particles which precipitated were washed with acetone and collected (10 mg).
NMR (DMSO-d 6 ): 11.85 (brs, 1H); 11.6 (brs, 1H); 10.33 (s, 1H); 8.27-8.03 (m, 3H); 7.7-7.5 (m, 5H); 7.27 (brs, 1H); 6.97 (brs, 1H); 6.77 (s, 1H); 4.5 (m, 2H); 3.15 (m, obscured by water peak); 2.03 (brs, 4H); 1.4 (m, 1H).
M.S. (F.A.B., glycerol+thioglycerol): 465 (M+H+H 2 ); 264, 202, 200, 187, 105.
UV (1% DMF in MeOH): λ max 364 (ε=29,000), 308 (ε=29,000).
EXAMPLE 36
Step 4-O-Deprotection; Step 5-Cyclization-1,2,8,8a-tetrahydro-7-methyl-2-[[5-benzoylamino-1H-indol-2-yl]carbonyl]cyclopropa[c]pyrrolo[3,2-e]indol-4(5H)-one
To 102 mg (0.126 mmol) of the protected mesylate suspended in 7 ml of dry benzonitrile under N 2 were added 150 mg (1 mmol) of dry NaI and 130 μl (1 mmol) of TMS-Cl. The reaction was heated to ˜60° for 50 min. It was cooled, diluted with ethyl acetate, and washed with 0.1M sodium thiosulfate, water and brine, and dried (Na 2 SO 4 ). The concentrated residue, dissolved in 500 μl of DMF was chromatographed on silica gel, eluting with 50% acetone in cyclohexane. The product-containing fractions also contained triethylammonium salt by NMR. They were dissolved in ethyl acetate and washed twice with water, then dried (NaHd 2SO 4 ) and stripped to 9.2 mg of a cream-colored solid.
NMR (DMSO-d 6 ): 11.9 (vbr, ˜1H); 11.8 (vbr, ˜1H); 11.65 (vbr, ˜1H); 10.28 (brs, ˜2H); 8.3-6.95 (m, ˜14H); 6.75 (s, 1H); 4.52 (m, 2H); methine obscured by water peak; 2.02 (brs, 4H); 1.4 (m, 1H).
M.S. (F.A.B., glycerol): 623 (M+H+H 2 ); (F.A.B., glycerol+thioglycerol): 621 (M+H); 421, 199, 186, 105.
UV (MeOH): λ max 360 nm (ε=27,500), 315 (ε=39,000).
EXAMPLE 37
Step 4-O-Deprotection; Step 5-Cyclization-1,3,8,8a-tetrahydro-7-methyl-2-[[5-cyanoamino-1H-indol-2-yl]carbonyl]cyclopropa[c]pyrrole[3,2-e]indol-4(5H)-one
To 63 mg (0.11 mmol) of the protected mesylate and 75 mg (0.5 mmol) of dry NaI in 3 ml of dry acetonitrile under N 2 was added 65 μl (0.5 mmol) of TMS-Cl. After heating to ˜60° for 50 min, the reaction was cooled, diluted with ethyl acetate, and washed with 0.1M sodium thiosulfate and then brine, and dried (Na 2 SO 4 ). Triethylamine (200 μl) was added and the solution was stored at 4° overnight. It was diluted with ethyl acetate, washed with water and brine and dried, and chromatographed on silica gel, eluting with 50% acetone in cyclohexane. The purest product fractions were concentrated to 6 mg of cream colored solid.
NMR (DMSO-d 6 ): 11.8 (brs 1H); 11.5 (brs, 1H); 9.9 (brs, 1H); 7.55-6.9 (m, 5-6H); 6.7 (s, 1H); 4.47 (m, 2H); 3.2 (m, obscured by water peak); 2.0 (brs, 4H); 1.38 (m, 1H).
M.S. (F.A.B., glycerol+thioglycerol): 384 (M+H); 269, 257, 199, 195, 184, 177.
UV (1% DMSO in MeOH): λ max 357 L nm (ε=15,500); 310, 295 nm (ε=16,700).
EXAMPLE 38
Step 4-O-Deprotection; Step 5-Cyclization-1,2,8,8a-tetrahydro-7-methyl-2-[[5-ureido-1H-indol-2-yl]carbonyl]cyclopropa[c]pyrrolo[3,2-e]indol-4(5H)-one
To 56 mg (0.095 mmol) of the protected mesylate in 3 ml of benzonitrile under N 2 were added 150 mg (1 mmol) of NaI and 130 μl (1 mmol) of TMS-Cl. The suspension was heated to ˜70° for 30 min, then cooled. It was diluted with ethyl acetate and washed with 0.1M sodium thiosulfate, water, and brine, and dried (Na 2 SO 4 ). The residue was chromatographed on silica gel, eluting with 70% acetone in cyclohexane. The fractions containing the product and its uncyclized precursor were concentrated, dissolved in 0.5 ml of acetone, and treated with 10 μl of triethylamine. The light yellow particles which precipitated were washed and collected (2.7 mg). A second crop of 6.7 mg was also obtained, but the extinction coefficient was 25% lower.
NMR (DMSO-d 6 ): 11.6 (vbr, ˜1H); 11.52 (vbr, ˜1H); 8.5 (brs, 1H); 7.86-6.9 (m, ˜5H); 6.71 (s, 1H); 5.75 (brs, 2H); 4.48 (m, 2H); methine obscured by water peak; 2.0 (brs, 4H); 1.35 (m, 1H).
M.S. (F.A.B., glycerol+thioglycerol): 402 (M+H); 200, 199, 149.
UV (1% DMSO in MeOH); λ max 362 nm (ε=15,000); 310 nm (ε=15,000).
EXAMPLE 39
Step 4-O-Deprotection; Step 5-Cyclization-1,2,8,8a-tetrahydro-7-methyl-2-[[5-[[[5-ureido-1H-indol-2-yl]carbonyl]amino]-1H-indol-2-yl]carbony]cyclopropa[c]pyrrolo[3,2-e]indol-4(5H)-one
To 39 mg (0.052 mmol) of the protected mesylate in 3 ml of dry benzonitrile under N 2 were added 100 mg (0.66 mmol) of NaI and 85 μl (0.66 mmol) of TMS-Cl. The mixture was heated to 80° for 30 min, then cooled and diluted with ethyl acetate. The organic phase was washed with 0.1M sodium thiosulfate and then brine, and dried (Na 2 SO 4 ). Triethylamine (50 μl) was added, causing instant clouding of the solution. This was concentrated and chromatographed on silica gel, adding a small amount of DMSO and 50 μl triethylamine before placing on the column. Elution with 70% acetone in cyclohexane removed non-polar components. The product was eluted with acetone. The product fractions were concentrated to 3 mg of a cream colored solid.
NMR (DMSO-d 6 ): 11.8 (vbr, ˜1H); 11.55 (vbr, ˜2H); 10.2 (brs, 1H); 8.4 (brs, 1H); 8.26 (brs, 1H); 7.83 (brs, 1H); 7.65-7.1 (m, ˜6H); 6.95 (m, 1H); 6.75 (s, 1H); 5.72 (brs, 2H); 4.53 (m, 2H); methine obscured by water peak; 2.0 (brs, 4H); 1.4 (m, 1H).
M.S. (F.A.B., glycerol+thioglycerol): 560 (M+H); 274, 232, 216, 199, 197.
UV (1% DMSO in MeOH): λ max 360 nm (ε=29,000); 312 nm (ε=40,000).
EXAMPLE 40
Step 4-O-Deprotection; Step 5-Cyclization-Cyclopropa[c]pyrrolo[3,2-e]indol-4(5H)-one, 1,2,8,8a-tetrahydro-7-methyl-2-(2-quinolinylcarbonyl)-
286 mg (0.52 mmol) quantity benzyl ether and 353 mg (2.4 mmol) dry sodium iodide was stirred under N 2 in 8 ml acetonitrile. Syringed in 288 μl (2.27 mmol) trimethylsilyl chloride. Refluxed for 30 min, TLC after 20 minutes showing no starting material left. The reaction mixture was cooled to RT and partitioned between EtOAc-2% sodium thiosulfate solution. The organic phase was dried over Na 2 SO 4 and treated with 900 μl triethylamine for 30 minutes, followed by evaporation under vacuum.
The crude product was chromatographed over 30 g silica gel, eluting with 300 ml 50% acetone-50% hexane-0.5% NEt 3 and 300 ml 60% acetone-40% hexane-0.5% NEt 3 . Fractions of 10 ml were collected, analyzing them by TLC. The major product spot was found in fractions 19-40, which upon combining and evaporating left a very insoluble tan solid weighing 81 mg (44% yield).
TLC: Silica gel; UV visualization; 50% acetone-50% hexane-0.5% NEt 3 ; R f : 0.42.
M.S.: M + found: 355.1298; calculated for C 22 H 17 N 3 O 2 : 355.1321. Other ions assigned: 327, 326, 228, 213, 199, 128.
NMR (d 6 -DMSO, TMS, δ): 1.45 (m, 1H); 1.96 (m, 1H); 2.0 (s, 3H); 3.1-3.3 (broad, 1H); 4.3-4.5 (m, 2H); 6.9 (s, 1H); 7.8-8.2 (m, 6H); 8.6-8.8 (d, 1H).
UV (0.01M phosphate, pH 7.2): A 357 =0.493; ε max =11,700.
EXAMPLE 41
Step-O-Deprotection; Step 5-Cyclization-Cyclopropa[c]pyrrolo[3,2-e]indol-4(5H)-one, 1,2,8,8a-tetrahydro-7-methyl-2-(2-pyrrolylcarbonyl)
A 0.19 mmol quantity crude benzyl ether and 131 mg (0.88 mmol) of dry sodium iodide were stirred under N 2 in 3 ml acetonitrile. Syringed in 107 μl (0.84 mmol) trimethylsilyl chloride and refluxed for 30 minutes. TLC after 25 minutes reaction had shown no starting material left. The reaction mixture was cooled to room temperature and partitioned between EtOAc-2% sodium thiosulfate. The organic layer was dried over Na 2 SO 4 and treated with 200 μl NEt 3 for 30 minutes, followed by evaporation under vacuum. The crude product was chromatographed over 15 g. silica gel, eluting with 50% acetone-50% hexane-0.2% NEt 3 . Fractions of 10 ml. were collected, analyzing them by TLC. Fractions 20-37 contained the product which shows up very bright under long wave length UV and were combined and evaporated. A 42 mg, residue was obtained which by NMR still contained a considerable amount of NEt 3 . Crystallization from acetone gave Group 1 (1.4 mg.) and Group 2 (9.0 mg.).
The mother liquors were rechromatographed over 3 g silica gel, eluting with 50% acetone-50% hexane-0.2% NEt 3 , followed by 75% acetone-25% hexane-0.2% NEt 3 when the product seemed to drop off. Fractions of 0.5 ml were collected, analyzing them by TLC. The product was found in fractions 11-67 which were combined and evaporated. Crystallization from acetone gave Group 3 (1.2 mg) which was combined with Groups 1 and 2.
TLC: Silica gel; UV visualization; 50% acetone-50% hexane-0.2% NEt 3 ; R f : 0.27.
NMR (d 6 -acetone, TMS, δ): 1.25-1.5 [m, 3H (includes ET 3 NH+X-)]; 2.3-2.45 (d, 3H); 3.15-3.75 [m, 3H (includes ET 3 NH+X-)]; 4.4-4.6 (m, 1H); 6.2-6.35 (broad, 1H); 6.75-6.9 (broad, 1H); 6.95-7.1 (broad, 2H); 7.6 (s, 1H).
M.S.: M + found: 293.1175; calculated for C 17 H 15 N 3 O 2 : 293.1164; other major assigned ion at 200.
______________________________________UV (0.01 M phosphate, pH 7.2).sup.λ max A .sup.ε max______________________________________310 shoulder 0.440 10,350368 0.455 10,700______________________________________
EXAMPLE 42
To a solution of the N-benzoyl cyclopropylspirodienone (estimated <10 mg) in 5 ml of methanol and 5 ml of water was added 2 ml of 40% CH 3 NH 2 in water. The mixture was stirred for 1 hr at 25°, then concentrated and worked up with aqueous NH 4 Cl and CH 2 Cl 2 . The organic phase was dried (Na 2 SO 4 ), concentrated, and chromatographed on silica gel, eluting with 10% methanol/CHCl 3 , to afford about 4 mg of a light tan solid.
EXAMPLE 43
Steps 7 and 8-Resolution of diastereomers (Chart III)
Step A-To 1.5 g. (3.89 mmol) of 1,2,3,6-tetrahydro-8-(methyl)-3-(methylsulfonyl)-5-(phenylmethoxy)-[1,2-6:4,3b']dipyrrole-1-methanol (see Chart III) in 60 ml. of methylene chloride was added 1.2 g. (3.95 mmol) of N-t-butoxycarbonyl-L-trypotphan, 0.77 g. (4.0 mmol) of ethyldimethylaminopropyl carbodiimide (HCl salt), and 0.08 g. (0.65 mmol) of 4-dimethylaminypyridine to form the racemic tryptophan ester. The mixture was stirred, under a nitrogen atmosphere, at room temperature for two days. It was then diluted with methylene chloride and extracted with 0.5% aqueous acetic acid, followed by saturated sodium chloride. The yellow solution was dried over Na 2 SO 4 and evaporated to 2.7 g. of yellow solid. The solid was dissolved in 10 ml. of tetrahydrofuran and 10 ml. of hexane was added to induce crystallization. Two further recrystallizations from tetrahydrofuran and hexane afforded crystals of >99% diastereomeric purity in 58% of theoretical yeild. Diastereomeric purity was determined by high pressure liquid chromatography on silica gel, eluting with 27% tetrahydrofuran in hexane, which gave baseline separation of the isomers.
NMR (CDCl 3 ): 8.4 (brs, 1H), 8.32 (brs, 1H), 7.7-7.0 (m, ˜12H), 5.22 (S, 2H), 5.1 (br, 1H), 4.7 (m, 1H), 4.35 (m, 1H), 3.9-3.2 (m, 6H), 2.7 (s, 3H), 2.4 (S, 3H), 1.5 (s, 9H).
Step B: To 1.1 g. (1.64 mmol) of the desired N-t-BOC-L-tryptophan ester from Step A in 20 ml. of tetrahydrofuran and 20 ml. of methanol under nitrogen was added, with stirring, 12 ml. of 1M aqueous sodium hydroxide to cleave the ester. After 1 hour at 20° C., the organic solvents were evaporated and the aqueous phase was extracted twice with ethyl acetate. The organic phase was washed once with 10% sodium bicarbonate and once with saturated NaCl, and dried over NA 2 SO 4 . Solvent evaporation afforded 0.57 g. (1.48 mmol, 90%) of a slightly yellow foam, whose NMR spectrum matched that of the starting material in Example 43.
NMR (acetone-d 6 ): 10.2 (brs 1H), 7.65-7.35 (m, 5H), 7.1 (nm, 2H), 5.26 (S, 2H), 4.3-3.45 (m, ˜5H), 2.82 (s, 3H), 2.4 (s, 3H).
Step C: When synthesis steps 1-5, described hereinabove, are carried out on this substance from Step B exactly as described in Examples 1, 7, 19 and 34, the product obtained is U-71,184, whose circular dichroism spectrum (methanol) exhibits peaks at 335 and 285 nm, and a trough at 315 nm, and whose non-chiral spectroscopic properties are identical to those of the racemate, U-68,415.
Examples 44 through 50, shown in Chart IV are illustrative of the steps in the process of preparing compounds wherein R 5 is the dimer combination xvii+xvii bound together with the amide linkage. The specific compound prepared is (7bR,8αS)-1,2,8,8α-tetrahydro-7-methyl-2-[[5-(((2H-benzofuran-2-yl)carbonyl)-amino)-1H-indol-2-yl]carbonyl]cyclopropa]pyrrolo[3,2-e]indol-4(5H)-one (U-73,975).
EXAMPLE 44
Step 1: Benzofuran-2-carboxylic acid (coumarilic acid, 1.5 mmol), described by R. Fittig, Ann., Vol. 216, 162 (1883), and 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDC, 1.64 mmol) were treated with 2.4 ml of a 0.6M solution of ethyl 5-amino-indole-2-carboxylate, described by M. A. Warpehoski, Tet. Lett., No. 24, (1986, pages 2735-2738, (which amino-ester is also referred to in footnote 11 of a paper by M. A. Warpehoski in Tetrahedron Letters, 27, No. 35, pages 4102-4106 (1986))) in dimethylformamide (DMF). The reaction was stirred under a nitrogen atmosphere for 40 hours and then diluted with ethyl acetate and water. The layers were separated and organic layer was washed with aqueous sodium bicarbonate, aqueous sodium bisulfate, and with brine, and then was dried over anhydrous sodium sulfate, and filtered. Removal of the solvent under reduced pressure afforded the crude product of Step 1. The crude product was chromatographed on silica gel eluting with 9:1 methylene chloride-acetone to give a 90% yield of pure product of Step 1. NMR(pyridine-d5, TMS): 1.20 (t, 3H); 4.40 (q, 2H); 7.20 top 7.95 (m, 6H); 8.10 (d, 1H); 8.20 (d, 1H); 8.75 (s, 1H); 8.81 (d, 1H); 11.2 (s, 1H) MS(FAB); Calc. for C 20 H 16 N 2 O 4 : 348.1110; Found: 348.1147; m/z 302,145,89; TLC (silica gel): R f =0.18 in (25-75)ethyl acetate-hexane.
EXAMPLE 45
Step 2: A solution of 0.29 mmol of the ester product of Step 1 in 4 ml of pyridine was treated with 0.4 ml of 1N aqueous sodium hydroxide solution, stirred for two days at room temperature, and quenched with 0.4 ml 1N aqueous hydrochloric acid. The resulting solution was partitioned between brine and tetrahydrofuran. The layers were separated and the organic layer dried over sodium sulfate and filtered. The solvents were removed in vacuo to give a quantitative yield of the crude product of Step 2 which was used without further purification. NMR (pyridine-d5, TMS): 7.15-7.95 (m, 7H); 8.05-8.25 (dd, 1H); 8.7-8.95 (m, 1H); 9.1 (s, 1H); 11.1 (s, 1H); 13.2 (s, 1H).
EXAMPLE 46
Step 3: Optically active n-mesylindoloindole (1,2,3,6-tetrahydro-8-(methyl)-3-(methylsulfonyl)-5-(phenylmethoxy)-[1,2-b:4,3-b']dipyrrole-1-methanol, 0.52 mmol), was dissolved in 20 ml of dimethoxyethane, treated under a nitrogen atmosphere dropwise with 1.1 ml of Red-Al (3.4M solution of bis(2-methoxy-ethoxy)aluminum hydride in toluene), heated at reflux for one hour, cooled to 0° C., and carefully quenched with 15% aqueous potassium carbonate. Using only nitrogen-purged solvents, the mixture was diluted with ether and water. The aqueous layer was re-extracted, and the combined ether layers were dried over anhydrous sodium sulfate, filtered and evaporated. The resulting crude oil was re-evaporated with toluene to give an air sensitive brown solid amine.
A solution of a total of 0.6 mmol of this amine in 2.3 ml of DMF and 0.6 mmol of EDC was added to a solution of 0.6 mmol of the acid product of Step 2 in 10 ml. of DMF. The resulting solution was stirred at room temperature for three days. The reaction mixture was diluted with methylene chloride and washed with 5% sodium bisulfate, 5% sodium bicarbonate and brine. The aqueous layers were back-extracted with methylene chloride. The organic layers were combined, dried over sodium sulfate and evaporated.
Crystallization from pyridine and methylene chloride afforded a 59% yield of the product of Step 3. NMR(acetone-d6, TMS): 2.4 (s, 3H); 3.2-5.2 (m, 6H); 5.1 (s, 3H); 6.8-7.9 (m, 14H); 8.2 (s, 1H); 8.45 (s, 1HO: 9.8 (s, 1H); 10.2 (s, 1H); 11.25 (s, 1H). MS (FAB): Calc. for C 37 H 30 N 4 O 5 : 610.2216; Found: 610.2209; m/z 687, 611,579,520,519,489,303, 277, 218, 187, 145; TLC (silica gel): R f =0.25 in (50-50) ethyl acetate-hexane.
EXAMPLE 47
Step 4: The starting alcohol (product of Step 3, 0.48 mmol) dissolved in pyridine (5 ml) was cooled in an ice bath and put under a nitrogen atmosphere. Methanesulfonyl chloride (169 μl, 2.18 mmol) was syringed into the reaction flask. Stirring at room temperature for 5-6 hours brought the reaction to completion. The reaction mixture was partitioned between ethyl acetate and 1N aqueous hydrochloric acid. The organic fraction was washed with brine, dried over anhydrous sodium sulfate, and filtered. The solvents were removed in vacuo to give essentially a quantitative yield of the crude product of Step 4. NMR (acetone-d6, TMS): 2.4 (s, 3H); 2.95 (s, 3H); 3.9-5.3 (m, 5H); 5.13 (s, 2H); 6.9-7.9 (m, 13H); 8.15 (s, 1H); 8.5 (S, 1H); 8.75 (d, 1H); 9.9 (s, 1H); 10.4 (d, 1H); 11.25 (s, 1 H). TLC (silica gel): R f =0.57 in (50-50) ethyl acetate-hexane.
EXAMPLE 48
Step 5: A solution of the crude product of Step 4 (approx. 0.48 mmol) in 5 ml. of DMF under a nitrogen atmosphere was treated with 55 mg of lithium chloride, heated at 75° C. for 2 hours, cooled to room temperature, and partitioned between ethyl acetate and 1:1 brine-water. The organic layers were washed with brine, dried over anhydrous sodium sulfate, and filtered. The solvent was removed under reduced pressure and the residue chromatographed on silica gel eluting with 40% ethyl acetate in hexane to give a 64% yield of the pure product of Step 5. NMR (CDCl 3 , TMS): 2.50 (d, 3H); 3.49 (t, 1H); 3.94 (dd, 1H); 4.13 (t, 1H); 4.67 (m, 1H); 4.90 (dd, 1H); 5.30 (d, 2H); 7.04 (m, 1H); 7.13 (d, 1H); 7.33-7.83 (m, 13H); 8.10 (s, 1H); 8.34 (s, 1H); 8.47 (s, 1H); 9.65 (s, 1H); 13 C-NMR (CDCl 3 , TMS): 11.254, 43.263, 46.989, 55.014, 70.317, 95.515, 105.971, 110.525, 110,979, 111.646, 112.007, 113.462, 114.063, 119.031, 122,690, 123,170, 123.718, 123.851, 123.213, 126.949, 127.684, 127.924(2), 128.084, 128.165, 128.458(2), 130.368, 131.650, 133.079, 136.551, 136.858, 145.137, 148.676, 154.658, 156.461, 159.559; MS(FAB): Calc. for C 37 H 29 Cl 1 N 4 O 4 : 628.1877; Found: 628.1896; m/z 629, 579, 537, 393, 327, 326, 303, 277, 236, 235, 199, 187, 145, 91; TLC (silica gel): R f =0.69 in (50-50) ethyl acetate-hexane.
EXAMPLE 49
Step 6: A solution of the product of Step 5 (0.26 mmol) in 4 ml of tetrahydrofuran and 2 ml of methanol at 0° C. was treated with 2.6 mmol of ammonium formate and 0.16 g of 10% palladium on charcoal, stirred at 0° C. for 30 minutes, filtered through celite and diluted with ethyl acetate. The ethyl acetate solution was washed with water and brine, dried over anhydrous sodium sulfate, and filtered. The solvents were removed in vacuo to give the product of Step 6 in 95% yield. NMR (DMF-d7, TMS): 2.432 (d, 3H); 3.61-3.75 (dd, 1H); 3.92-4.04 (dd, 1H); 4.04-4.19 (m, 1H); 4.67-4.84 (m, 2H); 7.15-7.90 (m, 9H); 8.42 (d, 1H); 9.87 (s, 1H); 10.55 (s, 1H); 10.75 (d, 1H); 11.66 (s, 1H); MS(FAB): Calc. for C 30 H 24 Cl 1 N 4 O 4 : 539.1486; Found: 539.1484; m/z 538, 505, 489, 303, 237, 236, 235, 201, 187, 145; UV (EtOH): λ max =209 (ε=42950), 219 (ε=39300), 346 (ε=26300); TLC (silica gel): R f =0.09 in (50-50) ethyl acetate-hexane.
EXAMPLE 50
Step 7: A solution of the product of Step 6 (0.19 mmol) in 5 ml acetonitrile, 4 ml of triethylamine, and 16 ml of water was stirred for 30 minutes at room temperature and then cooled 0° C. The resulting solid which precipitated during the course of the reaction was collected by vacuum filtration and dried in vacuo to give an 80% yield of pure (7bR,8αS)-1,2,8,8α-tetrahydro-7-methyl-2-[[5-(((2H-benzofuran-2-yl)carbonyl-amino)-1H-indol-2-yl]carbonyl]cyclopropa]pyrrolo[3,2-e]indol-4(5H)-one (U-73,975). NMR (DMF-d7, TMS): 1.49-1.54 (t, 1H); 2.04-2.10 (m, 1H); 2.102 (s, 3H); 3.24-3.31 (m, 1H); 4.57-4.72 (m, 2H); 6.84 (s, 1H); 7.03 (d, 1H); 7.32 (d, 1H); 7.39-7.92 (m, 7H); 8.46 (d, 1H); 10.60 (s, 1H); 11.57 (s, 1H); 11.83 (s, 1H). MS (FAB): Calc. for C 30 H 23 -N 4 O 4 : 503.1719; Found: 503.1742; m/z 303, 201, 199, 187, 145; UV (EtOH): λ max =2.10 (ε=39700), 312 (ε=37440), 365 (ε=31110); TLC (silica gel): R f =0.22 in (40-60) acetone-hexane.
Many of the compounds of the subject invention have useful cytotoxic activity against murine L1210 tumor cells in suspension, which is a standard model for such tests before the compounds are tested in humans. If a compound is active against such tumor cells, then it presumptively will have activity against tumor cells in other animals and humans. Following is a table showing the results of testing various compounds against L1210 in suspension using standard, well-known procedures. The compounds are identified by an internal designation called "U-" number. The structural identify of the "U-" numbered compounds is shown in Chart I.
______________________________________ L-1210 (3-Day Cell Growth) ID.sub.50 ID.sub.90Compound μg/ml μg/ml______________________________________U-62,736 0.039 0.18U-66,777 0.18 0.92U-66,866 0.0015 0.0045U-68,880 0.0000080 0.000019U-68,415 0.000018 0.000044U-68,819 0.00048 0.0015U-66,694 0.00015 0.00034U-67,785 0.000072 0.00019U-67,786 0.000046 0.00010U-68,749 0.0034 0.0084U-68,846 0.000034 0.000096U-66,664 0.0048 0.018U-66,665 0.0090 0.032______________________________________
Examples of compounds of the subject invention demonstrate antitumor activity in P388 leukemic mice, and also show significant activity in the L1210 leukemia and B16 melanema murine test systems. These murine test systems are predictive for clinically useful human antitumor agents (see, for example, A. Geldin, J. M. Vendetti, J. S. MacDonald, F. M. Muggia, J. E. Henney and V. T. DeVita, European J. Cancer, Vol. 17, pp. 129-142, 1981; J. M. Vendetti, Cancer Treatment Reports, Vol. 67, pp. 767-772, 1983; and J. M. Vendetti, R. A. Wesley, and J. Plowman, Advances in Pharmacology and Chemotherapy, Vol. 20, pp. 1-20, 1984), and it is therefore presumed that the compounds of the subject invention will be useful in the control and treatment of cancer in humans when given, for example, intravenously in doses of 0.001 to about 10 mg. per kg. of body weight per day, the exact dose depending on the age, weight and condition of the patient, and on the frequency of administration. Following is a table showing the results of testing various compounds intraperitoneally against P388 leukemic mice using standard well-known procedures (In Vivo cancer, Models, NIH Publication No. 84-2635, 1984). The structural identify of the "U-" numbered compounds is shown in Chart I. In the table %ILS refers to percent increase in life span of treated animals over controls.
______________________________________Compound P388 % ILS______________________________________U-66,866 71 (at 12 mg./kg.)U-68,880 71 (at 0.10 mg./kg.)U-68,415 4/6 cures (at 0.05 mg./kg.)U-68,819 71 (at 1 mg./kg.)U-66,694 164 (at 0.63 mg./kg.)U-63,749 113 (at 6 mg./kg.)U-68,846 82 (at 0.05 mg./kg.)U-69,059 4/6 cures (at 0.5 mg./kg.)U-67,785 60 (at 0.06 mg./kg.)U-69,058 96 (at 0.50 mg./kg.)U-69,060 138 (at 0.10 mg./kg.)______________________________________
The compound U-73,975, a compound wherein R 5 is the dimer combination xvii and xvii bound together with the amide linkage, has exhibited particularly good activity against solid tumors as well as having shown good solubility and stability characteristics in aqueous solution. For example, in B16 melanoma implanted subcutaneously in mice, a 61% increase in life span over control (non-drug treated) animals was observed with a single intravenous dose of U-73,975 significantly increased the lifespan of mice implanted with M5076 ovarian sarcoma and Lewis carcinoma. U-73,975 also significantly inhibited the growth of a human lung tumor (Lx-1 carcinoma) xenograph in nude mice. These characteristics are advantageous for antitumor agents.
All the compounds of the subject invention have UV absorption in the range of 250 nm to 380 nm. Thus, novel compounds of the subject invention are useful as UV absorbents in technical and industrial areas, as follows:
(a) textile materials, for example, wool, silk, cotton, hemp, flax, linen and the like; and
(b) natural or synthetic resins.
Depending on the nature of the material to be treated, the requirements with regard to the degree of activity and durability, and other factors, the proportion of the light screening agent to be incorporated into the material may vary within fairly wide limits, for example, from about 0.01% to about 10%, and, advantageously, 0.1% to 2% of the weight of the material which is to be directly protected against the action of UV rays.
The compounds of this invention have anti-microbial activity and hence are useful as anti-bacterialagents. For example, compounds 5 (U-66,665) and 6 (U-66,694) have activity against the following microorganisms:
Bacillus subtilis, Klebsiella pneumonia, Sarcina lutea, Escherichia coli, Proteus vulgaris, Staphylococcus aureus, Salmonella schottmeulerri, Mycobacterium avium, Saccharomyces pastorianus, and Penicillium oxalicum and compound U-73,975 has activity against Escherichia coli, Klebsiella pneumonia, and Staphyloccocus areus. Compounds 5 are those obtained from Step 4 in Charts I and II, illustratively U-66,665. Compounds 6 are those obtained from Step 5 in Charts I and II, illustratively U-66,694.
Thus, these compounds are useful to control the proliferation of these microbes in various environments using standard microbiological techniques. Such environments include laboratory benches in a microbiological laboratory which can be cleansed with a formulation of the above compounds; dental utensils contaminated with S. aureus, and the like.
In a manner analogous to that of Examples 2-13 the following carboxylic acids may be coupled to the pyrroloindole product formed in Example 1. Mesylation of these coupled products in like manner to Examples 14-25, followed by deprotection and ring closure as described for Examples 26-41, will provice the structures indicated and named. ##STR36## Cyclopropa[c]pyrrol[3,2-e]indol-4(5H)-one, 1,2,8,8a-tetrahydro-2-(1-methylindol-2-ylcarbonyl)-7-methyl- ##STR37## Cyclopropa[c]pyrrolo[3,2-e]indol-4-(5H)-one, 1,2,8,8a-tetrahydro-2-[[5-[[[5-[(1H-indol-2-ylcarbonyl)amino]-1H-indol-2-yl]carbonyl]amino]-1H-indol-2-yl-carbonyl]-7-methyl- ##STR38## Cyclopropa[c]pyrrolo[3,2-e]indol-4[5H)-one, 1,2,8,8a-tetrahydro-2-[[5-[(1H)-indol-2-ylcarbonyl)methylamino]-1H-indol-2-yl]carbonyl]-7-methyl- ##STR39## Cyclopropa[c]pyrrolo[3,2-e]indol-4-(5H)-one, 1,2,8,8a-tetrahydro-2-[[6-benzoyl-amino)-quinolin-2-yl]carbonyl]-7-methyl- ##STR40## Cyclopropa[c]pyrrolo[3,2-e]indol-4(5H)-one, 1,2,8,8a-tetrahydro-2-[[6-[(1H)-indol-2-ylcarbonyl)amino]-quinolin-2-yl]carbonyl]-7-methyl- ##STR41## Cyclopropa[c]pyrrolo[3,2-e]indol-4-(5H)-one, 1,2,8,8a-tetrahydro-2-(picolinyl-2-yl)carbonyl-7-methyl- ##STR42## Cyclopropa[c]pyrrolo[3,2-e]indol-4(5H)-one, 1,2,8,8a-tetrahydro-2-7-methyl-2-(2-naphthaleneylcarbonyl)- ##STR43## Cyclopropa[c]pyrrolo[3,2-]indol-4(5H)-one, 1,2,8,8a-tetrahydro-2-(1H)-benzothiophen-2-ylcarbonyl)-7-methyl- ##STR44## Cyclopropa[c]pyrrolo[3,2-e]indol-4(5H)-one, 1,2,8,8a-tetrahydro-2[[6-hexanoylamino-quinolin-2-yl]carbonyl]-7-methyl- ##STR45## Cyclopropa[c]pyrrolo[3,2-e]indol-4(5H)-one, 1,2,8,8a-tetrahydro-2-(1H)-benzofuran-2-yl-carbonyl)-7-methyl ##STR46## Cyclopropa[c]pyrrolo[3,2-e]indol-4(5H)-one, 1,2,8,8-tetrahydro-2-heaxnoyl-7-methyl- ##STR47## | 1,2,8,8a-Tetrahydrocyclopropa[3]pyrrolo(3,2-e)indol-4(5H)-ones, and related compounds of formulas I and intermediate therefor II ##STR1## wherein R 2 , R 2 ', R 3 , R 5 , R 50 and X are as defined in the specification, e.g., (7bR,8aS)-1,2,8,8a-tetrahydro-7-methyl-2-[[5-(((1H-indol-2-yl)carbonyl)amino)-1H-indol-2-yl]carbonyl]cyclopropa[pyrrolo[3,2-e]indol-4(5H)-one (U-71,184), as purified, and its racemic form (U-68,415), and related compounds, are useful as ultraviolet light absorbers and as antibacterials. The lead compounds are useful as antitumor drug compounds in standard laboratory animal tests. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a detection circuit, and particularly, it relates to a detection circuit for detecting a predetermined signal from a composite signal of two signals such as an oscillation gyroscope.
2. Description of the Prior Art
In a conventional gyroscope as the background of the present invention, for example, an oscillator in which a piezoelectric element is formed respectively on three side faces of a triangular prism-shaped oscillating body is used.
In the oscillation gyroscope, two out of these piezoelectric elements are used for detection, and these two piezoelectric elements or the other one piezoelectric element are used for driving.
In this oscillation gyroscope, when the driving signal is applied to the driving piezoelectric element, the oscillating body starts to oscillate. When the oscillator is rotated in this state, an output difference is produced between the two piezoelectric elements for detection, thereby the rotational anglar velocity can be known.
In this oscillation gyroscope, however, due to the processing distortion and stress of the oscillator, variations and accuracy of processing and assembling of the piezoelectric elements and the difference in their thermal expansion coefficients, temperature change and aging occur, thereby an drift component is contained in the output difference between the two piezoelectric elements for detection.
In order to prevent malfunction by the drift component, though a threshold level of an amplifier is set suitably so as not to output the input signal of the drift component level, or a DC surbo circuit is provided, or a high pass filter is disposed to change the circuit time constant, by these means, the change of output difference by the drift component and the change of output difference due to the fine rotational angular velocity can not be distinguished, and their minimum resolving power is poor and the time constant remains, thus the problem occurs in the linearity of output difference against the response speed and the rotational angular velocity.
SUMMARY OF THE INVENTION
Therefore, it is a primary object of the present invention to provide a detection circuit capable of suppressing a drift component.
The present invention is directed to the detection circuit which includes a first synchronism detection circuit for synchronous detection of an input signal, a second synchronism detection circuit for synchronous detection of the input signal separately from the first synchronism detection circuit, a phase-shifting circuit for bringing a phase difference between the first synchronism detection circuit and the second synchronism detection circuit, a first smoothing circuit for smoothing the output of the first synchronism detection circuit, a second smoothing circuit for smoothing the output of the second synchronism detection circuit and a composite circuit for composing the outputs of the first smoothing circuit and the second smoothing circuit.
The input signal is subjected to the synchronous detection in the first synchronism detection circuit. This input signal is also subjected to the synchronous detection in the second synchronism detection circuit. In this case, since the phase difference is caused between the first synchronism detection circuit and the second synchronism detection circuit by the phase-shifting circuit, there is the phase difference between the outputs of the first synchronism detection circuit and the second synchronism detection circuit.
The outputs of the first synchronism detection circuit and the second synchronism detection circuit are smoothed respectively in the first smoothing circuit and the second smoothing circuit.
In the composite circuit, the outputs of the first smoothing circuit and the second smoothing circuit are composed.
A description of using an input signal which includes a drift component will be described.
The drift component appears in the input signal as a phase shift. Therefore, due to the drift component, the output from the first synchronism detection circuit is distorted and the output of the first smoothing circuit is reduced.
Meanwhile, from the second synchronism detection circuit, an output which compensates the output distortion of the first synchronism detection circuit is obtained, and from the second smoothing circuit, an output which compensates the output reduction of the first smoothing circuit is obtained.
The outputs of the firs smoothing circuit and the second smoothing circuit are composed by the composite circuit, so that the output of the composite circuit is obtained as the output in which the drift component is suppressed.
According to the present invention, the detection circuit capable of suppressing the drift component is obtained.
Accordingly, when this detection circuit is used, for example, in an oscillation gyroscope, the output linearity against the rotational angular velocity can be improved irrespective of the presence of the drift component.
The above and other objects, features and aspects of the present invention will become more apparent from the following detailed description of embodiments with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 a block diagram showing an example of an oscillation gyroscope as one embodiment of the present invention.
FIG. 2 is a circuit diagram showing a feedback loop of the oscillation gyroscope of FIG. 1.
FIG. 3 is a circuit diagram showing a differential amplifying circuit, a first synchronism detection circuit and a first smoothing circuit of the oscillation gyroscope of FIG. 1.
FIG. 4A and FIG. 4B are graphs respectively showing output waveforms of respective portions of the oscillation gyroscope of FIG. 1, FIG. 4A shows when the drift comonent is not contained in the output of the differential amplifying circuit, and FIG. 4B shows when the drift component is contained.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 is a block diagram showing an example of an oscillation gyroscope as one embodiment of the present invention. Though the oscillation gyroscope is described in the embodiment, it will be indicated in advance that the present invention can be applied in any apparatus obtaining a predetermined signal from the composite signal of two signals, such as a speed sensor or an acceleration sensor besides the oscillation gyroscope.
The oscillation gyroscope 10 includes an oscillator 11 which includes, for example, a regular triangular body 12 is constituted by a material which produces, generally, a mechanical oscillation such as elinvar, iron-nickel alloy, quartz, glass, crystal, ceramic.
On the oscillation body 12, piezoelectric elements 14a, 14b and 14c are formed respectively at the center of three side faces thereof. The piezoelectric element 14a includes a piezoelectric layer 16a consisting of, for example, ceramic, and electrodes 18a and 20a are formed respectively on the surfaces of the piezoelectric layer 16a. The electrodes 18a and 20a are formed with an electrode material such as gold, silver, aluminum, nickel, copper-nickel alloy (Monel metal), by means of a thin-film technique such as sputtering and vacuum evaporation, or depending upon the material, by a printing technique. Similarly, the other piezoelectric elements 14b and 14c respectively include piezoelectric layers 16b and 16c consisting of, for example, ceramic, and electrodes 18b, 20b and 18c, 20c are formed respectively on the surfaces of the piezoelectric layers 16b and 16c. The electrodes 18a to 18c on one side of the piezoelectric elements 14a to 14c are bonded to the oscillating body 12 by means of a conductive adhesive.
The oscillating body 12 is supported by a supporting member (not shown) consisting of, for example, a metal wire in the vicinity of its node point. The supporting member is secured to the oscillating body 12 in the vicinity of the node point by, for example, wedding. The supporting member may be secured by a conductive paste. The supporting member is used as a ground terminal of the oscillation gyroscope 10.
In the oscillator 11, any two piezoelectric elements of the piezoelectric elements 14a to 14c are used for detection, and this two or other one piezoelectric element are used for driving. In this embodiment, for example, two piezoelectric elements 14a and 14b are used for driving and detection. Also, the other piezoelectric element 14c is used for feedback. When the driving signal is applied to the driving and detecting piezoelectric elements 14a and 14b, the oscillating body 12 starts to oscillate, and similar sine waves are output from the piezoelectric elements 14a and 14b. When the oscillator 11 is rotated about its axis in that state, the output of one detecting piezoelectric element increases according to the rotational angular velocity, and conversely, the output of the other detecting piezoelectric element will decrease.
Between the feedback piezoelectric element 14c and the driving piezoelectric elements 14a, 14b of the osillation gyroscope 10, an oscillation circuit 30 is connected as a feedback loop for self-oscillation driving of the oscillation gyroscope 10.
As shown in FIG. 2, the oscillation circuit 30 is constituted by, for example, an inversion amplifying circuit including an operational amplifier 32. The inversion amplifying circuit is designed to inverse the output phase from the feedback piezoelectric element 14c and to amplify its signal.
Furthermore, an output terminal of the oscillation circuit 30 is, as shown in FIG. 1, connected to an input terminal of a phase-shifting circuit 40.
As shown in FIG. 2, the phase-shifting circuit 40 includes, for example, two-stage RC filters 42 and 44, each having a lagging power-factor of, for example, 45 degree. The phase-shifting circuit 40 is designed to delay the output phase from the oscillation circuit 30 by 90 degree, and to suppress the high-frequency component included in the output. The output side of the rear-stage RC filter 44 is connected to the electrode 20a of the piezoelectric element 14a via a resistance 46a, and to the electrode 20b of the piezoelectric element 14b via a separate resistance 46b.
Meanwhile, as shown in FIG. 1, the piezoelectric elements 14a and 14b of the oscillation gyroscope 10 are connected respectively to two input terminals of a differential amplifying circuit 50 for detecting their output difference.
That is, as shown in FIG. 3, the differential amplifying circuit 50 includes, for example, an operational amplifier 52, to the non-inversion input terminal and inversion input terminal of which, the electrodes 20a and 20b of the piezoelectric elements 14a and 14b are connected respectively. Moreover, to the output side of the operational amplifier 52, a capacitor 54 and a resistance 56 for coupling are connected in series.
As shown in FIG. 1, the output terminal of the differential amplifying circuit 50 is connected to a first synchronism detection circuit 70a and a second synchronism detection circuit 70b constituting a portion of a detection circuit 60.
Since the first synchronism detection circuit 70a and the second synchronism detection circuit 70b have the same circuit configuration, particularly, the first synchronism detection circuit 70a is described in detail with reference to FIG. 3.
That is, an shown in FIG. 3, the first synchronism detection circuit 70a includes, for example, an FET 72 whose source is connected to the resistance 56 of the differential amplifying circuit 50. A drain of the FET 72 is grounded. Moreover, a gate of the FET 72 is connected to the input side of the RC filter 42 (refer to FIG. 2) of the phase-shifting circuit 40 via a resistance 74. The gate of the FET 72 is also grounded via a separate resistance 76. Accordingly, to the gate of the FET 72, the input side signal of the RC filter 42 of the phase-shifting circuit 40 is applied in the form of partial pressure through the resistances 74 and 76.
Though the circuit configuration of the second synchronism detection circuit 70b is similar to that of the first synchronism detection circuit 70a, to the gate of the FET, the output side signal of the RC filter 44 (refer to FIG. 2) of the phase-shifting circuit 40 is applied in the form of partial pressure through two separate resistances.
Accordingly, by the phase-shifting circuit 40, there is a phase difference of 90 degree between the first synchronism detection circuit 70a and the synchronism detection circuit 70b.
Also, as shown in FIG. 1, the first synchronism detection circuit 70a and the second synchronism detection circuit 70b are connected respectively to input terminals of a first smoothing circuit 80a and a second smoothing circuit 80b.
As shown in FIG. 3, the first smoothing circuit 80a includes two-stage RC filters 82 and 84, the front-stage RC filter 82 being connected to the source of the FET 72 of the first synchronism detection circuit 70a.
The second smoothing circuit 80b has the same circuit configuration as the first smoothing circuit 80a, and its front-stage RC filter is connected to a source of the FET of the second synchronism detection circuit 70b.
Furthermore, as shown in FIG. 1, output terminals of the first smoothing circuit 80a and the second smoothing circuit 80b are connected to two input terminals of a DC amplifying circuit 90 as a composite circuit. As the DC amplifying circuit 90, an amplifying circuit such as a differential amplifying circuit is used.
Next, the operation of the respective circuits of the osillation gyroscope 10 will be explained with reference to FIG. 1 through FIG. 3 and FIGS. 4A, 4B. In FIG. 4A, the output of the first synchronism detection circuit 70a, the output of the second synchronism detection circuit 70b, the output of the first smoothing circuit 80a, the output of the second smoothing circuit 80b and the output of the DC amplifying circuit 90 in case the drift component is not contained in the output of the oscillator 11 or in the outputs of the piezoelectric elements 14a and 14b for detection, are shown, and in FIG. 4B, those outputs in case the drift component is contained in the outputs of the piezoelectric elements 14a and 14b are shown.
Since the output of the feedback piezoelectric element 14c of the oscillator 11 is fed back to the driving piezoelectric elements 14a and 14b by the oscillation circuit 30 and the phase-shifting circuit 40 as the feedback loop, the oscillation gyroscope 10 is self-oscillated. In this case, the output of the feedback piezoelectric element 14c is delayed by 180 degree in the oscillation circuit 30, by 90 degree in the two-stage RC filters 42 and 44 of the phase-shifting circuit 40, and further, by 90 degree by the electrostatic capacity of the resistances 46a, 46b and the driving piezoelectric elements 14a, 14b, and fed back to the piezoelectric elements 14a and 14b. Therefore, the output of the feedback piezoelectric element 14c and the input of the driving piezoelectric elements 14a and 14b become in-phase, thereby the oscillator 11 is self-oscillated efficiently.
In the oscillation gyroscope 10, in case the oscillator 11 is rotated in one direction about its axis, for example, the output of one detecting piezoelectric element 14a increases and the output of the other piezoelectric element 14b will decrease. Thus, the output difference therebetween is output as a sine wave from the differential amplifying circuit 50.
The output of the differential amplifying circuit 50 is subjected to synchronous detection in the first synchronism detection circuit 70a. In this embodiment, the output of the differential amplifying circuit 50 is passed only on the positive side in the first synchronism detection circuit 70a. Therefore, as shown in FIG. 4A, the output of the first synchronism detection circuit 70a takes the waveform of half-wave rectification of only the positive side of the sine wave. Moreover, the output of the first synchronism detection circuit 70a is rectified in the first smoothing circuit 80a into the positive direct current.
Also, the output of the differential amplifying circuit 50 is subjected to synchronous detection at the 90 degree phase lag, by the second synchronism detection circuit 70b. Accordingly, the output of the second synchronism detection circuit 70b, as shown in FIG. 4A, takes the heteroformal waveform having a substantially triangular wave of the same size respectively on the positive and negative sides. Furthermore, though the output of the second synchronism detection circuit 70b is rectified in the second smoothing circuit 80b, since the output of the second synchronism detection circuit 80b appears in the same magnitudes on the positive and negative sides, the output of the second smoothing circuit 80 becomes zero.
The outputs of the first smoothing circuit 80a and the second smoothing circuit 80b are composed in the DC amplifying circuit 90.
Accordingly, the output of the detection circuit 60 becomes the direct current, which is obtained by smoothing the half-wave rectified output of the differential amplifying circuit 50.
Meanwhile, the drift component may be contained in the outputs of the detecting piezoelectric elements 14a and 14b by change in temperature and with time. Such a drift component appears as a phase shift in the outputs of the piezoelectric elements 14a and 14b. For example, the output phases of both the piezoelectric elements 14a and 14b are delayed.
In the case of containing such drift component, though the output of the differential amplifying circuit 50 becomes the sine wave of the same size, its phase delays more or less by the drift component, as compared with the case containing no drift component.
In this case, as shown in FIG. 4B, the output of the first synchronism detection circuit 70a is deleted at a portion corresponding to a substantially triangular wave preceding in the waveform obtained by the half-wave rectification of the sine wave, and becomes the heteroformal waveform having a substantially triangular wave of the size corresponding to that portion on the negative side. Therefore, the output of the first smoothing circuit 80a becomes somewhat smaller as compared with the case wherein the drift component is not contained.
As the output of the differential amplifying circuit 50 delays a little, as shown in FIG. 4B, the output of the second synchronism detection circuit 70b becomes smaller on the positive side and larger on the negative side. The output of the second smoothing circuit 80b becomes a negative direct current which is substantially the same magnitude as the decreased output of the first smoothing circuit 80a.
As such, since the output of the second smoothing circuit 80b becomes the negative direct current which is substantially the same magnitude as the decreased output of the first smoothing circuit 80a, the output of the DC amplifying circuit 90 becomes substantially the same magnitude as the case containing no drift component.
Accordingly, in the detection circuit 60, even when the drift component is contained in the input signal, a predetermined output signal in which the drift component is suppressed is obtained.
While, as the rotational angular velocity of the oscillation gyroscope 10 becomes larger, the output difference of the piezoelectric elements 14a and 14b or the output of the differential amplifying circuit 50 becomes larger, so that the output of the detection circuit 60 also becomes larger. Therefore, the rotational angular velocity of the oscillation gyroscope 10 may be known from the magnitude of the output of the detection circuit 60.
Accordingly, in the oscillation gyroscope 10, from the magnitude of the output of the detection circuit 60, the rotational angular velocity can be known also for the case wherein the drift component is contained, as same as the case wherein the drift component is not contained.
When the oscillation gyroscope 10 is rotating in the opposite direction, since the magnitude of the outputs of the piezoelectric elements 14a and 14b are reversed, a negative direct current is output from the detection circuit 60. Accordingly, from the output polarity of the detection circuit 60, a rotating direction of the oscillation gyroscope 10 may be known.
Meanwhile in the oscillation gyroscope 10, in case the oscillator 11 is not rotated, a same sine wave is output from the piezoelectric elements 14a and 14b, and the output of the differential amplifying circuit 50 or the detection circuit 60 becomes zero, it is known that the oscillation gyroscope 10 is not rotating.
In the embodiment aforementioned, though the phase difference between the first synchronism detection circuit 70a and the second synchronism detection circuit 70b is made at 90 degree by the phase-shifting circuit 40, in order to make the phase difference at 90 degree, in place of the phase-shifting circuit 40, a phase-shifting circuit having a phase of 90 degree may be disposed at the front stage of one synchronism detection circuit, or the phase-shifting circuits having each other the phase difference of 90 degree may be disposed respectively at the front stage of the two synchronism detection circuits.
The phase difference between the first synchronism detection circuit 70a and the second synchronism detection circuit 70b may be set at other magnitudes such as 30 degree, 45 degree or 60 degree besides 90 degree, in this case, the drift component can also be suppressed.
Although the present invention has been described and illustrated in detail, it is clearly understood that the same is by way of illustration and example only and is not to be taken by way of limitation, the spirit and scope of the present invention being limited only by the terms of the appended claims. | The detection circuit includes a first synchronism detection circuit for synchronous detection of an input signal. A second synchronism detection circuit synchronously detects the input signal separately from the first synchronism detection circuit. A phase-shifting circuit outputs differently phased signals to the first synchronism detection circuit and the second synchronism detection circuit. A first smoothing circuit smooths the output of the first synchronism detection circuit. A second smoothing circuit smooths the output of the second synchronism detection circuit. A composite circuit adds the outputs of the first smoothing circuit and the second smoothing circuit. Even when a drift component is contained in the input signal, the detection circuit will output a predetermined output signal in which the drift component is suppressed. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a method of and an apparatus for polishing a fiber. According to the present invention, deposits such as silicon and the like adhered to a fiber, for example such as the bare fiber or core of an optical fiber is removed when the core of the optical fiber is polished.
2. Description of the Prior Art
The optical fibers are employed in various industrial fields, and remarkably widespread among them.
Each of the optical fibers consists mainly of: its core a diameter of which is on the order of 0.1 mm; and a cladding member with which the core of the optical fiber is covered. Consequently, in the case of splicing the optical fibers, the optical fibers to be joined are stripped of their protective coating or cladding members over predetermined lengths from their ends so as to prepare their joining ends, and after that the thus prepared ends are polished to remove the deposits such as silicon and the like.
Hitherto, in the case of polishing the core of the optical fiber, since as shown in FIG. 1 it is difficult to hold the optical fiber 1 and since the fiber 1 is very brittle to make it difficult to rotate the fiber 360 degrees on its axis, the core 3 of the fiber 1 is intermittently rotated up to 180 degrees on its axis while sandwiched between cloths 2 in which a suitable polishing agent or wiping solvent such as alcohol and the like has been absorbed. Under such circumstances, the cloths 2 are axially moved relative to the core 3 of the optical fiber 1 to wipe and polish the core 3.
Such conventional polishing work of the core 3 of the optical fiber 1 is conducted manually or mechanically. However, since it is hard to hold the optical fiber 1, the conventional polishing work of the core 3 of the fiber 1 takes much time and labor to impair workability and productivity in mass production. In addition, the conventional polishing work is also disadvantageous in that it is completely difficult to polish the base of the core 3 of the optical fiber 1.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a method of polishing in a short time a fiber such as an optical fiber which is difficult to rotate 360 degrees, in an easy manner.
It is another object of the present invention to provide an apparatus for working the above method of the present invention.
The above first object of the present invention is accomplished by providing:
A method of polishing a fiber comprising the steps of:
bringing a thread-like polishing medium into contact with an outer peripheral portion of the fiber; and
moving axially and rotatably the thread-like polishing medium relative to the outer peripheral portion of the fiber;
whereby the fiber is polished with the thread-like polishing medium.
In the method of the present invention, since the thread-like polishing medium is axially and rotatably moved relative to the fiber as described above, it is possible to easily polish in a short time the fiber such as the optical fiber which is difficult to rotate 360 degrees.
The above another object of the present invention is accomplished by providing:
An apparatus for polishing a fiber comprising:
a hollow rotary shaft disposed in a polishing position of the fiber, the hollow rotary shaft being rotatably driven by a driving unit and provided with: a medium-entrance opening at its one end, through which medium-entrance opening the thread-like polishing medium enters the hollow rotary shaft; and a medium-exit opening at the other end thereof, through which medium-exit opening the thread-like polishing medium is discharged from the hollow rotary shaft;
an unwind-bobbin assembly for supplying the thread-like polishing medium to the fiber, the unwind-bobbin assembly being provided with a sufficient amount of the thread-like polishing medium and coaxially and fixedly mounted on the hollow rotary shaft; and
a wind-up bobbin for receiving the thread-like polishing medium having been supplied from the unwind-bobbin assembly through the medium-entrance and -exit openings of the hollow rotary shaft, the wind-up bobbin being rotatably driven by the driving unit or by another driving unit so that the thread-like polishing medium having been supplied from the unwind-bobbin assembly is wound on the wind-up bobbin;
whereby the fiber having been inserted into the interior of the hollow rotary shaft through the medium-entrance opening or the medium-exit opening of the hollow rotary shaft is polished at its outer peripheral portion with the thread-like polishing medium moved axially and rotatably relative to the fiber.
In the apparatus of the present invention, the thread-like polishing medium supplied from the unwind-bobbin assembly is transferred through the interior of the hollow rotary shaft while rotatably driven by the hollow rotary shaft so as to be wound around the wind-up bobbin, whereby the outer peripheral portion of the fiber is polished with the thread-like polishing medium moved axially and rotatably relative to the fiber. As described above, in the apparatus of the present invention, it is possible to polish the outer peripheral portion of the fiber by simply inserting the fiber into the hollow rotary shaft of the apparatus through the medium-entrance opening or the medium-exit opening of the hollow rotary shaft, namely, at this time, it is not required to rotate the fiber itself to any extent during the polishing operation thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a view illustrating a conventional method of polishing the fiber;
FIG. 2 is a partially sectional front view of an embodiment of the apparatus of the present invention;
FIG. 3 is a longitudinal sectional view of an upper half of the hollow rotary shaft assembly of the apparatus of the present invention shown in FIG. 2;
FIG. 4 is a cross-sectional view of the unwind-bobbin assembly of the apparatus of the present invention, taken along the line A--A of FIG. 2; and
FIG. 5 is a cross-sectional view of the fiber to be polished in the apparatus of the present invention shown in FIG. 2, for illustrating the relationship between the fiber and the thread-like polishing mediums during the polishing operation conducted in the apparatus of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
An apparatus of the present invention for polishing a fiber such as the core of an optical fiber is shown in FIGS. 2 and 3 in which the reference numeral 12 denotes a hollow rotary shaft provided with: a medium-entrance opening 15a at its one end, through which opening 15a a thread-like polishing medium 11 enters the interior of the hollow rotary shaft 12; and a medium-exit opening 15b at the other end thereof, through which opening 15b the thread-like polishing medium 11 is discharged from the interior of the hollow rotary shaft 12.
The hollow rotary shaft 12 is supported by bearing portions 22, and driven by a suitable driving unit "a".
As shown in FIG. 2, the driving unit "a" consist of: a motor 17 having an output shaft 18 on which is fixedly mounted an output pulley 19. An endless belt 21 runs round the output pulley 19 and an input pulley 20 fixedly mounted the hollow rotary shaft 12 to transmit torque from the output shaft 18 to the hollow rotary shaft 12 through the endless belt 21.
An unwind-bobbin assembly 13 is coaxially and fixedly mounted on the hollow rotary shaft 12 in the vicinity of the medium-entrance opening 15a thereof. The unwind-bobbin assembly 13 is provided with: a pair of flanges 13a, 13b which are axially and oppositely disposed from each other through an axial barrel portion 30; and a plurality of unwind bobbins 34 on each of which a sufficient amount of the thread-like polishing medium is wound, the unwind bobbins 34 being so rotatably mounted between the flanges 13a, 13b that they are substantially parallel to the axial barrel portion 30 and spaced apart from each other in a circumferential direction of the hollow rotary shaft 12.
A wind-up bobbin 14 is coaxially and rotatably mounted on the hollow rotary shaft 12 in the vicinity of the medium-exit opening 15b thereof. The wind-up bobbin 14 is provided with an axial barrel portion 31 an end of which forms a flange 14a which cooperates with another flange 33 in the winding operation of the thread-like polishing medium to prevent the thread-like polishing medium from dropping out of the axial barrel portion 31 of the wind-up bobbin 14. Such another flange 33 is fixedly mounted on the hollow rotary shaft 12 as is clear from FIG. 3.
The wind-up bobbin 14 is connected to the driving unit "a" through a rotation-control mechanism "b" as shown in FIG. 2. The rotation-control mechanism "b" is provided with a clutch 29 for coupling or uncoupling the output shaft 18 of the motor 17 and an output shaft 28 of an output pulley 26. An endless belt 27 runs round the output pulley 26 and an input pulley 25 which is rotatably mounted on the hollow rotary shaft 12. On the other hand, as shown in FIG. 3, the input pulley 25 is connected with the wind-up bobbin 14 through a plurality of axial pins 40 which are spaced apart from each other in a circumferential direction of the wind-up bobbin 14. Consequently, in the apparatus of the present invention having the above construction: torque is transmitted from the output shaft 28 to the wind-up bobbin 14 through the endless belt 27; and both of the ratios of the output pulley 26 to the input pulley 25 and of the output pulley 19 to the input pulley 20 in diameter are so determined that, in the coupling (or normal running) position of the clutch 29, the rotational speed of the wind-up bobbin 14 is larger that that of the hollow rotary shaft 12.
Incidentally, in the apparatus of the present invention, it is also possible to allow the rotational speed of the wind-up bobbin 14 to be smaller than that of the hollow rotary shaft 12, whereby the thread-like polishing medium 11 is wound on the wind-up bobbin 14 in a direction reverse to that of the above case.
As shown in FIG. 3, a flange 37 is fixedly mounted on the hollow rotary shaft 12 in the vicinity of the input pulley 25. A pressing ring 41 is slidably mounted on the hollow rotary shaft 12 in a position between the flange 37 and the input pulley 25, while slidably connected with the flange 37 through a plurality of axial pins 42 arranged in a circumferential direction of the flange 37. On each of the axial pins 42 is mounted a compression spring 23. Under the influence of the resilient force of the compression spring 23, the pressing ring 41 is spring pressed against the input pulley 25. As shown in FIG. 3, a friction disk 24 is sandwiched between surfaces of the pressing ring 41 and the input pulley 25, which surfaces are oppositely disposed from each other.
An axial sliding motion of the input pulley 25 is restricted by a stop ring 43 as shown in FIG. 3. When the motor 17 is actuated and the clutch 29 is in the coupling (or normal running) position, the input pulley 25 is rotatably driven at a rotational speed larger or smaller than that of the hollow rotary shaft 12 against the frictional resistance caused by the friction disk 24. On the other hand, when the clutch 29 is in the uncoupling position thereof, the input pulley 25 is prevented from freely rotating under the influence of the frictional resistance of the friction disk 24 so that the input pulley 25 rotates at the same rotational speed as that of the hollow rotary shaft 12.
In case that detergents are supplied to the fiber 10, the detergents are ejected to the medium-entrance opening 15a of the hollow rotary shaft 12 from the outside. It is also possible to provide a polishing-agent reservoir 36 in the interior of the hollow rotary shaft 12, in which reservoir 36 is received a suitable liquid polishing agent such as alcohol, lapping compounds and the like to make it possible to always supply the polishing agent to the thread-like polishing medium 11 and thus to the fiber 10.
In case that the polishing agent is liquid, it is preferable that such liquid polishing agent is absorbed in a suitable absorbent such as a cloth.
Preferably, the thread-like polishing medium is constructed of cotton yarn which is excellent in both of liquid-absorption capacity and tensile strength.
Now, hereinbelow will be described in detail how to operate the apparatus of the present invention having the above construction.
At first, the thread-like polishing mediums 11 wound on the unwind bobbins 34 of the unwind-bobbin assembly 13 are inserted into the interior of the hollow rotary shaft 12 through the medium-entrance opening 15a thereof, and passed through the interior of the hollow rotary shaft 12 and its medium-exit opening 15b so as to be discharged from the hollow rotary shaft 12. The thus discharged thread-like polishing mediums 11 are wound on the wind-up bobbin 14 firmly through guide rollers 35 which are rotatably mounted on the flange 33.
Then, the motor 17 is actuated, and the clutch 29 is coupled so that the unwind-bobbin assembly 13 is rotated together with the hollow rotary shaft 12. At this time, the wind-up bobbin 14 is also rotated on the axis of the hollow rotary shaft 12 at a rotational speed larger or smaller than that of the hollow rotary shaft 12 to cause the wind-up bobbin 14 to wind the thread-like polishing mediums 11 (which are transferred in the direction of the arrow shown in FIG. 3) thereon. Under such circumstances, the fiber 10 to be polished is inserted into the interior of the hollow rotary shaft 12 through the medium-entrance opening 15a or the medium-exit opening 15b of the hollow rotary shaft 12. As a result, the thread-like polishing mediums 11 are axially and rotatably moved relative to the fiber 10 so that the outer peripheral portion of the fiber 10 is sufficiently polished with the thread-like polishing mediums 11.
After that, the clutch 29 is uncoupled so that, under the influence of the frictional resistance of the friction disk 24, the wind-up bobbin 14 is rotated at the same rotational speed as that of the hollow rotary shaft 12. Consequently, in this state, the thread-like polishing mediums 11 are not transferred in the direction of the arrow shown in FIG. 3. Under such circumstances, the thread-like polishing mediums 11 are moved only rotatably relative to the fiber 10 to polish the same.
In general, at the beginning stage of the polishing operation, since a relatively large amount of deposits adheres to the fiber 10, it is necessary for the thread-like polishing mediums 11 to combine their rotational movements with their axial movements in order to accomplish a sufficient polishing operation of the fiber 10. However, in the next stage of the polishing operation following the above beginning stage, it is preferably to conduct the polishing operation only by the use of the rotational movements of the thread-like polishing mediums 11. Incidentally, it is entirely in the operator's discretion whether he combines the rotational movements of the thread-like polishing mediums 11 with their axial movements in the next stage of the polishing operation following the beginning stage.
As is clear from FIG. 2, it is also possible to polish the fiber 10 with the thread-like polishing mediums 11 in the medium-exit opening 15b of the hollow rotary shaft 12. | A method of polishing a fiber, which is particularly difficult to rotate 360 degrees in its polishing operation, comprises the steps of: bringing a thread-like polishing medium into contact with an outer peripheral portion of the fiber; and moving axially and rotatably the thread-like polishing medium relative to the outer peripheral portion of the fiber; whereby the fiber is polished with the thread-like polishing medium. | 1 |
RELATED APPLICATIONS
Not applicable.
FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not applicable.
MICROFICHE APPENDIX
Not applicable.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention pertains generally to methods and devices for sensing angular positions and, more particularly, to methods and devices for detecting and providing feedback of the angular position of a rotary control valve.
2. Description of the Prior Art
Rotary control valves, such as butterfly valves or ball valves, include a valve body and a plate, ball, or other flow control member rotatably mounted in the valve body to either block fluid flow through the valve, or allow fluid flow through the valve, depending upon the angular position of the flow control member. For example, a ball valve includes a ball which is securely mounted to upper and lower portions of a valve shaft. The ball is mounted in the fluid flow path of the valve by mounting the lower portion of the valve shaft in a lower portion of the valve body and the upper portion of the valve shaft in an upper portion of the valve body, with the ball positioned between the upper and lower shaft portions in the fluid flow path of the valve. An actuator is attached to the upper portion of the valve shaft, which extends through the valve body. When the actuator is turned, the valve shaft, and, therefore, the valve ball, is rotated. The ball is shaped, i.e., portions of the ball are removed or grooves are formed therein, such that when the ball is rotated, through, e.g., 90°, the fluid flow path through the valve is gradually opened or closed.
It is often desirable to determine accurately the angular position of the ball within the ball valve, and therefore, the state, i.e., open, closed, or somewhere in between, of the valve. Several methods of automatically determining the angular position of a valve are known. Sensing the angular position of the valve may be accomplished by attaching an angular position sensor to the valve actuator. For example, magnets may be attached to the rotating member of the valve actuator, and a Hall effect sensor used to determine the position of the actuator as the actuator member, therefore, the magnets attached thereto, is rotated. As the actuator member is rotated, the magnetic field produced by the magnets attached to the actuator is also rotated. The Hall sensor is placed within the magnetic field produced by the magnets. As the direction of the magnetic field changes, as the actuator is rotated, the Hall effect sensor detects the change and provides a signal from which the rotary position of the actuator can be determined.
Alternatively, a cam may be attached to the actuator shaft. The angular position of the actuator shaft is then converted to an electrical signal by an inductive sensor connected or in close proximity to the cam. As the actuator is rotated, the cam attached thereto is also rotated, which, in turn, changes the inductance of the inductive sensor in contact with or in close proximity to the cam. Thus, a signal is provided by the inductive sensor which is related to the angular position of the actuator and from which the angular position of the actuator can be determined.
As a third alternative, a potentiometer may be connected to the rotating member of the valve actuator. As the actuator member is rotated, the potentiometer potential is changed. This change in potential can be detected and signal derived therefrom from which the angular position of the actuator can be determined.
All known methods for determining the angular position of a valve by mounting a rotary position sensor on the valve actuator, however, suffers from a serious limitation. For a ball valve, for example, an accurate determination of the rotary position of the valve ball is desired. Although the valve actuator is connected, via the valve shaft, to the valve ball, there could be some inherent looseness in this connection. Even if the connection between the valve actuator and the ball is initially tight, this connection can fail or become looser with time. Thus, sensing the angular position of the valve actuator will not necessarily translate into an accurate indication of the position of the valve flow control member.
In order to determine the angular position of the flow control member more accurately, the angular position sensing methods described above have been employed to sense the position of the lower portion of the valve shaft which is directly connected to the flow control member. Since the shaft is directly and tightly connected to the flow control member, sensing the angular position of the shaft will result in an accurate determination of the angular position of the flow control member itself. Any of the angular position sensing methods described above may be used to determine the angular position of the valve shaft. For example, a magnet may be attached to the lower portion of the valve shaft, and a Hall sensor placed near the magnet. As the valve shaft, and, therefore, the flow control member itself, rotates, the magnetic field produced by the magnet attached to the valve shaft changes direction. This change in direction is detected by the Hall effect sensor, which provides a signal related to the angular position of the angular shaft member from which the angular position of the flow control member can be determined accurately.
Alternatively, a potentiometer can be attached to the lower portion of the valve shaft. As the shaft, and, therefore, the flow control member itself, is rotated, the potential of the potentiometer is changed. This change can be sensed, and a signal provided from which the angular position of the flow control member can be determined accurately.
Although measuring the angular position of a flow control member by sensing the angular position of the lower portion of the valve shaft can achieve accurate results, known methods for making such measurements suffer from other limitations. In order to measure the movement of the lower portion of the valve shaft, with a potentiometer or another device, the lower portion of the valve shaft must be extended through the bottom of the valve, and the potentiometer or other measurement device attached to the shaft on the outside of the valve. Extending the lower portion of the valve shaft thus provides another leak path from the valve, and the added packing adds friction to the valve. Also, extending the lower portion of the shaft through the valve body makes the valve more fragile during moving and handling of the valve.
As an alternative to extending the lower portion of the valve shaft through the valve body, the potentiometer or other device for sensing angular position of the shaft may be extended through an aperture in the valve body near the end of the shaft. For example, a potentiometer may be mounted on the outside of the valve body. An elongated shaft attached to the potentiometer may be extended through an aperture in the valve body wall and be connected to the lower portion of the valve shaft. Alternatively, a Hall effect device may be mounted within the valve body, near a magnet placed on the flow control member or lower portion of the valve shaft, with conducting wires for conducting the signal provided by the Hall effect sensor passing through a hole in the valve body. In either case, the addition of another aperture to the valve body provides another potential leak path from the valve, and therefore, adversely affects valve integrity.
Another limitation of Hall effect and other magnetic field sensors employed to detect the angular position of the lower shaft of a rotary control valve is the effect of temperature changes on the accuracy of such devices. Changes in temperature of the magnet mounted on the lower portion of the valve shaft and the magnetic field sensing device itself can affect the signal provided by the sensor. Temperature changes, can, therefore, affect the accuracy of the angular position sensed by such a detector unless temperature compensation is provided.
SUMMARY OF THE INVENTION
The present invention provides for accurate detection of the angular position of a valve flow control member in a rotary control valve using magnets mounted in the bottom end of the lower portion of a valve shaft, which is tightly connected to the flow control member, and a magnetic field sensor, mounted outside of the valve pressure boundary, for detecting changes in the magnetic field produced by the magnets as the valve flow control member is rotated. Since, in this manner, the angular position of the lower valve shaft is determined directly, and since the lower valve shaft is tightly connected to the flow control member, the present invention provides a highly accurate determination of the angular position of the valve flow control member. Furthermore, since angular position detection in accordance with the present invention employs magnets which are mounted entirely within the valve, and a magnetic field sensor which is mounted entirely outside of the valve, the present invention allows accurate angular position detection to be achieved without the need for providing another hole through the valve, which would add another leak path from the valve, require additional packing, and make the valve more fragile.
In accordance with a first embodiment of the present invention a rotary control valve includes a ball, disk, or other flow control member, which is tightly connected to a valve shaft. The lower portion of the valve shaft is mounted on the inside of a lower portion of the valve wall. In accordance with the present invention, the lower portion of the valve shaft is made of a non-magnetic material, and has two magnets retained in cavities formed on each side of and extending parallel to the axis of rotation of the valve shaft. The magnets are oriented such that the north pole of one of the magnets and the south pole of the other magnet are near the bottom end of the valve shaft. A plate of ferrous material may be used to connect the other, upper, ends of the magnets through an opening in the valve shaft which extends between the cavities in which the magnets are retained. The purpose of the plate of ferrous material is to increase the strength of the magnetic field created between the lower ends of the magnets near the bottom of the lower portion of the valve shaft. An arching magnetic field is thus produced between the lower poles of the magnets at the bottom of the lower portion of the valve shaft. This arching magnetic field extends beyond the end of the valve shaft, and through the lower portion of the valve wall that is in close proximity to the end of the shaft. The lower portion of the valve wall penetrated by the magnetic field is made of a non-magnetic material.
A magnetic field sensor, such as a giant magneto resistive (GMR) sensor or a Hall effect sensor, is placed in the magnetic field created by the magnets on the outside, or unpressurized side, of the non-magnetic lower portion of the valve wall. The output signal provided by the magnetic field sensor is dependent on the strength and direction of the magnetic field in which the sensor is placed. As the lower portion of its valve shaft, and, therefore, the valve flow control member, is rotated, a sensor signal provided by the magnetic field sensor varies as the angular position of the magnets mounted in the lower portion of the valve shaft varies. Thus, the signal produced by the magnetic field sensor indicates the angular position of the valve flow control member. The sensor signal produced by the magnetic field sensor can be converted by a signal conditioner into an analog or digital signal format. This signal can be processed and transmitted to a position attached to or near the valve for accurate control of the valve flow control member position, and/or can be displayed at a local or remote location.
In an alternative embodiment of the present invention, the lower valve shaft, which is tightly connected to the valve flow control member, contains a cylindrical opening formed therein extending from the bottom of the shaft and centered on the axis of rotation of the shaft. Magnets are placed in two recesses formed in the shaft on opposite sides of the cylindrical opening. The magnets are placed in the recesses such that opposite poles point toward each other across the cylindrical opening to create a magnetic field within the cylindrical opening. A lower portion of the valve wall is formed to include an extension which extends into the cylindrical opening in the lower valve shaft. This lower portion of the valve wall is made of a non-magnetic material. A cavity is formed in the extending portion of this non-magnetic lower portion of the valve wall, on the outside of the valve wall, such that the magnetic field produced by the magnets in the valve shaft is also present within the cavity. A magnetic field sensor, such as a magneto-resistive sensor or a Hall effect sensor is placed in the magnetic field within the cavity. The magnetic field sensor produces a sensor signal which is dependent on the strength and direction of the magnetic field in which the sensor is mounted. Thus, as the lower portion of the valve shaft, and therefore, the flow control member, rotates, the sensor signal provided by the magnetic field sensor varies as the angular position of the magnets mounted in the valve shaft changes. Thus, the sensor signal provided by the magnetic field sensor provides an accurate indication of the angular position of the valve flow control member. The sensor signal can be converted by a signal conditioner into any analog or digital format, processed, and transmitted to a position attached to or near the valve to accurately control the position of the valve flow control member, and/or to the local or remote location for display.
The accuracy of rotary valve angular position detection in accordance with the present invention is improved by making the detection of the angular position of the valve flow control member insensitive to temperature changes in the magnets mounted in the lower valve shaft and the magnetic field strength sensor employed. This is achieved by using two magnetic field sensors mounted on the outside of the lower portion of the valve wall within the magnetic field produced by the magnets mounted in the lower valve shaft. The magnetic field sensors are mounted on the valve such that the active axes of the two sensors are oriented in the same plane but angularly displaced from each other. By combining the sensor signals provided by the two magnetic field sensors, the angular position of the valve flow control member can be calculated in a manner in which the first order dependence of position signal versus temperature is canceled out. Thus, in accordance with the present invention, the angular position of a flow control member in a rotary control valve can be determined under various temperature conditions.
Further objects, features and advantages of the present invention will be apparent from the following detailed description taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an illustration, in cross-section, of an exemplary rotary control valve including angular position detection in accordance with the present invention.
FIG. 2 is a detailed side view, in partial cross-section, of a portion of an exemplary rotary control valve incorporating position detection in accordance with a first embodiment of the present invention.
FIG. 3 is a bottom view of the portion of the exemplary rotary control valve of FIG. 2 .
FIG. 4 is a detailed illustration, in partial cross-section, of a portion of an exemplary rotary control valve incorporating angular position detection in accordance with a second embodiment of the present invention.
FIG. 5 illustrates the preferred angular relationship between the active axes of two magnetic field sensors used for temperature insensitive angular position detection of a rotary control valve in accordance with the present invention.
FIG. 6 is a graph of exemplary output voltage profiles for two magnetic field sensors used for temperature insensitive angular position detection in accordance with the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention provides accurate position detection for a rotary control valve. The present invention may be applied to any type of rotary control valve, such as a ball valve, a butterfly valve, or a plug valve, having any type of rotatable flow control member, such as a ball, disk, or plug. For exemplary purposes only, the present invention will be described with reference to application to a ball type rotary control valve.
An exemplary ball type rotary control valve 10 incorporating angular position detection in accordance with the present invention is illustrated in and will be described in detail with reference to FIG. 1 . The exemplary rotary control valve 10 includes a valve body 12 having a fluid flow path 14 therethrough. A rotatable flow control member 16 , in this case a ball, is mounted within the valve body 12 in the fluid flow path 14 of the valve 10 . The ball 16 is rotatable, e.g., through 90° arc, between fully open and fully closed positions. In the fully closed position, as illustrated in FIG. 1, the ball 16 entirely blocks the fluid flow path 14 through the valve 10 . The ball 16 is mounted on a valve shaft having upper 18 and lower 20 portions. The upper 18 and lower 20 portions of the valve shaft are, in turn, mounted in the valve body 12 for rotational movement therein. The valve shaft 18 extends through the upper portion of the valve body 12 . Packing 24 is placed around the valve shaft 18 where it extends through the valve body 12 , to prevent leakage from the inside of the valve to the outside thereof around the shaft 18 . When the shaft 18 is rotated, either by hand or by some other mechanism, the ball 16 is rotated to open and close the fluid flow path 14 through the valve 10 .
The lower portion 20 of the valve shaft is tightly coupled to the valve ball 16 . Therefore, the angular position of the valve ball 16 can be determined accurately from the angular position of the lower portion 20 of the valve shaft. In accordance with the present invention, accurate position detection of the valve ball 16 is achieved, therefore, by mounting magnets 26 in the lower portion 20 of the valve shaft. The magnets 26 are mounted in the lower portion 20 of the valve shaft so as to create a magnetic field which extends outside of the valve body 12 . The lower portion of the valve shaft 20 and a lower portion 28 of the valve body 12 are made of non-magnetic materials which do not interfere with the magnetic field created by the magnets 26 . Note that the non-magnetic lower portion 28 of the valve body 12 may be formed as a separate piece of non-magnetic material which is tightly attached, via bolts 29 , screws, or another mechanism to the bottom of the valve body 12 adjacent the lower portion 20 of the valve shaft.
A magnetic field sensor 30 is mounted on the outside or within a cavity of the non-magnetic portion 28 of the valve body 12 , within the magnetic field created by the magnets 26 . The magnetic field sensor 30 may be implemented as a Hall effect sensor, or as a magneto-resistive sensor, such as a GMR sensor manufactured and sold by Non-Volatile Electronics, Inc. of Eden Prairie, Minn. The magnetic field sensor 30 produces an output signal which depends on the strength and direction of the magnetic field passing through the sensor. Thus, as the valve ball 16 , and therefore, the lower portion of the valve shaft 20 rotates, the magnetic field produced by the magnets 26 mounted in the lower portion of the valve shaft 20 also rotates, and the sensor signal provided by the magnetic field sensor 30 varies with the angular position of the magnets 26 . Thus, the signal produced by the magnetic field sensor indicates the angular position of the valve ball 16 . The sensor signal produced by the magnetic field sensor 30 may be converted by a signal conditioner into any analog or digital format which may be processed and/or displayed in a conventional manner.
FIGS. 2 and 3 illustrate, in more detail and by example, the mounting of the magnets 26 in the lower portion 20 of the valve shaft in an exemplary embodiment of the present invention. The lower valve shaft 20 , which is made of a non-magnetic material, has two magnets 26 a and 26 b mounted therein in parallel cavities formed near the bottom end of the lower valve shaft 20 . The two magnets 26 a and 26 b are thus mounted in the lower portion of the valve shaft 20 in parallel both with each other and with the axis of rotation of the valve shaft. The magnets 26 a and 26 b are oriented such that the north pole of one of the magnets and the south pole of the other of the magnets are nearest the end of the lower portion of the valve shaft 20 . A plate of ferrous material may be mounted in the lower portion 20 of the valve shaft to connect the other, upper ends of the magnets 26 a and 26 b together. The piece of ferrous material 27 acts to increase the strength of the magnetic field produced between the lower ends of the magnets 26 a and 26 b . In the position illustrated in FIGS. 2 and 3, the magnets 26 a and 26 b produce an arcing magnetic field between their lower poles. This arcing magnetic field extends beyond the end of the lower portion of the valve shaft 20 and into or through the non-magnetic lower portion 28 of the valve body 12 .
The magnetic field sensor 30 is mounted either within or on the non-magnetic lower portion 28 of the valve body, within the arcing magnetic field produced by the magnets 26 a and 26 b . As discussed previously, as the lower portion of the valve shaft 20 is rotated, the magnetic field produced by the magnets 26 a and 26 b is also rotated. As the direction of the magnetic field changes, the output signal produced by the magnetic field strength sensor 30 also changes. Since the lower portion of the valve shaft 20 is tightly connected to the valve ball 16 , the angular position of the valve ball 16 can be accurately determined from the signal produced by the magnetic field strength sensor 30 . The signal produced by the magnetic field strength sensor 30 may be provided on a line 32 to a remote processor and/or display system, wherein the angular position of the valve ball 16 may be displayed to a user and/or may be used as feedback to an automated mechanism for opening and closing the valve ball 16 via a valve shaft 18 .
An alternative exemplary embodiment of a rotary control valve incorporating angular position detection in accordance with the present invention is illustrated in and will be described in detail with reference to FIG. 4 . In this case, the lower portion of the valve shaft 20 , which is made of a non-magnetic material and which is tightly connected to the valve ball, has a cylindrical opening 34 formed therein extending from the bottom of the lower portion of the valve shaft 20 and centered on the axis of rotation of the lower portion of the valve shaft 20 . Two magnets 26 a and 26 b are mounted in recesses on opposite sides of the lower portion of the valve shaft 20 . The magnets 26 a and 26 b are mounted in the lower portion of the valve shaft 20 such that opposite poles of the magnets 26 a and 26 b point toward each other across the cylindrical opening 34 in the valve shaft 20 , to create a magnetic field within the cylindrical opening 34 . The lower portion of the valve body 28 , which is also made of a non-magnetic material, includes an extending portion 36 which extends into the cylindrical opening 34 in the lower portion of the valve shaft 20 . The extending portion 36 of the lower portion of the valve body 28 forms a cavity on the outside of the valve body which also extends into the cylindrical opening 34 formed in the lower portion of the valve shaft 20 , such that the magnetic field created by the magnets 26 a and 26 b is present in this cavity. The magnetic field sensor 30 is mounted within this cavity, on the outside of the valve body, within the magnetic field created by the magnets 26 a and 26 b . As discussed previously, as the valve ball, and, therefore, the lower portion of the valve shaft 20 is rotated, a signal provided by the sensor 30 will vary as the direction of the magnetic field detected by the sensor 30 changes. 10 As described previously, this signal may be processed and displayed in a conventional manner, and/or used as feedback to control an automatic valve control mechanism connected to the valve shaft.
The angular position signal provided by the magnetic field sensor 30 is sensitive to changes in temperature in the magnets 26 mounted in the lower portion of the valve shaft 20 , and changes in temperature of the sensor 30 itself. These changes may be caused, for example, by changes in temperature of the fluid flowing through or contained by the valve 10 . These temperature caused changes in the output of the sensor 30 can adversely affect the accuracy of the detected angular position of the valve ball. In accordance with the present invention, accurate angular position detection using magnetic field sensing is made temperature insensitive by the use of two magnetic field sensors.
Assume that the lower portion of the valve shaft 20 is rotatable through a 90° arc from 0° (valve closed) to 90° (valve open). The two 25 magnetic field sensors preferably are mounted such that their active axes are aligned at equal angles between 0 and 45° on opposite sides of the halfway angle of rotation (e.g., 45°) of the lower portion of the valve shaft. Thus, assume that the first sensor is oriented at some angle, φ 1 , between 0° and 45°. The second sensor is oriented at an angle φ 2 , between 45° and 90°. The two sensor angles preferably satisfy the equation 45°−φ 1= φ 2 −45°. relationship is illustrated in FIG. 5, i.e., φ 1+ φ 2 =90° or complementary angles.
As the valve ball is rotated, the direction of the magnetic field with respect to the active axes of the magnetic field sensors changes. For the case in which the sensors are mounted at angles φ 1 =30.6° and φ 2= 59.4°, exemplary output voltages for the two sensors as the valve angle changes from 0° to 90° are illustrated in the profile of FIG. 6 . The alignment of the two sensors in the manner described avoids the zero field condition, which is a problem region in some magnetic field sensors, such as magneto-resistive sensors.
From the output signals provided by the two magnetic field sensors, the valve angle can be calculated. A mathematical derivation of the valve angle as a function of two sensor voltages uses the following relationships for the two sensor voltages:
V 1 =S nom ·H nom ·[1+σ 1° T S ]·[1+η T M ]·cos(⊖ v−φ 1 +φ el )+ V ofsl +V n1 (1)
V 2 S nom ·H nom· [1+σ 2° T S ]·[1+η T M]·cos(θ v −φ 2 +φ e2 )+ V ofs2 +V n2 (2)
Assume the following:
σ 1 = σ 2
(The tempcos for the two sensors are identical.)
φ e1 = φ e2 = 0
(There is no error in sensor's orientation.)
V ofs1 = V ofs2 = 0
(Adjusted during calibration.)
V n1 = V n2 = 0
(Noise-free analysis.)
These assumptions are made to simplify the analysis in order to illustrate the basic measurement procedure and its advantages. The calculation of the valve angle is now derived as θ v = arctan [ cos ( φ 2 ) · V 1 - cos ( φ 1 ) · V 2 sin ( φ 1 ) · V 2 - sin ( φ 2 ) · V 1 ] , ( 16 )
Note that by calculating the valve angle in the manner described, the temperature dependence of the magnetic field sensor and the magnets has been canceled by the formation of a tangent function. Thus, the need for further temperature compensation of the sensor's signal is eliminated. Thus, in accordance with the present invention, highly accurate angular position detection can be achieved for various changing operating temperatures.
It is understood that the invention is not confined to the particular examples and embodiments herein illustrated and described, but embraces all such modified forms thereof as come within the scope of the following claims. | A rotary control valve includes a flow control element having a lower valve shaft rotatably received in a non-magnetic body portion. A magnet is coupled with a lower valve shaft and rotatable therewith to produce an external magnetic field that varies in accordance with the angular position of the flow control element. A magnetic field detector, positioned in the external magnetic field, is operable to detect the external magnetic field and to produce position signals representative thereof, such being indicative of the angular position of the flow control element. | 5 |
FIELD OF THE INVENTION
The invention relates to natural sweeteners, and more particularly to a low calorie composite sweetener as a sugar alternative comprising a blend of sugar and natural high intensity sweetener and further to a method for producing the low calorie composite sweetener.
BACKGROUND OF THE INVENTION
Sugar-high intensity sweetener blends have been formulated to produce low calorie composite sweeteners, being used as sugar alternatives with reduced calorific values. Aside from having lower calorific value, it is important that the low calorie composite sweetener as a sugar alternative shall have similar appearance, taste profile, bulk properties and heat resistance as sucrose. For example, the similar appearance would enable a sugar alternative to have a decorative function in addition to sweetening and bulking properties; the heat resistance is essential for a large number of food and beverage applications that operate at high temperature; otherwise a sugar alternative with low heat resistance tends to degrade when subjected to heat.
Various methods for production of such blends have been developed to produce low calorie sweetener compositions.
U.S. Pat. No. 6,214,402 describes a co-crystallization process between sugar and N-{N-(3,3-dimethylbutyl)-L-alpha-aspartyl}-L-phenylalanine 1-methylester. It comprises the steps of mixing sugar with water, heating the mixture to 120° C., then seeding the mixture with a pre-mixture comprising N-{N-(3,3-dimethylbutyl)-L-alpha-aspartyl}-L-phenylalanine 1-methylester and sugar, followed by allowing the resulted mixture to cool at intensive stirring conditions. It is to noted that the process was carried out under normal atmospheric pressure conditions, and high temperatures, particularly 120° C. In this case, darkening of mixture promoted by high temperature might occur which in turn affects the color and appearance of the final product. Another drawback of the method is the high power consumption of employed processes.
US Patent Application 2010/0034945 describes a process of preparation of co-crystallized product comprising sugar and a natural sweetener. The product is prepared by co-crystallizing sucrose and a natural sweetener in a vacuum pan under controlled pressure and temperature conditions followed by separating the crystal from the “sugar juice”. The drawback of this process when it is employed for co-crystallization of sugar and high intensity sweetener is the difficulty of controlling the ratio of sugar and high intensity sweetener in the final crystals. The distribution of high intensity sweetener between two phases (crystals and “sugar juice”) can have significant variance which, in case of high sweetness power of aforementioned sweeteners will result in substantial batch to batch variability of sweetness level of final product. Besides, in order to prevent loss of high intensity sweetener which remains in liquid phase, additional recovery/recirculation steps are required.
European Patent EP0334617 describes a sweetener which comprises hollow spheroids or part spheroids of microcrystalline sucrose generally bound to crystals of sucrose and preferably containing one or more high intensity sweeteners such as sucralose. The sweetener is prepared by spray drying of sucrose syrup with simultaneous injection of an inert pressurized gas and generally contacting the sprayed syrup during the spray drying step and/or after completion of said step with crystals of sucrose and preferably incorporating the high intensity sweetener in the sucrose syrup or in the agglomeration step. A major setback of this method for production of low caloric sweetener composition which utilizes sucrose in the form of syrup as raw material, is the high power consumption and requirement of custom designed high cost equipment for spray drying process.
UK Patent GB1566821 describes a sweetening composition comprising a mixture of L-sorbose and sucrose with molar ratio of L-sorbose to sucrose within the range of 1:0.5 to 1:50. The sweetening composition is prepared by mixing granulated/powdered sucrose and L-sorbose together. A sugar-high intensity sweetener blends prepared by simple dry mixing process tends to have lower quality especially after prolonged transportation and storage when stratification of components occurs due to influence of vibration and friction.
U.S. Pat. No. 3,619,294 describes a process where Massecuite Aggregated Microcrystalline Sugar (MAMS) granules (structurally comprising cohered sugar microcrystals with internal capillary networks) are employed as a means to combine sugar with modifying agents. The disclosed process is dependent upon the internal capillary networks of the MAMS granules, which allow the applied modifying agent to impregnate the sugar granules. The disclosed process further provides an option of second treatment in which a pore closure material is applied to reduce the porosity of the surface layers of the granules, and seal off the impregnated agent from escape to or contact with the atmosphere. The drawbacks of the disclosed process include the requirement of special forms of sugar granules and additional sealing treatment.
U.S. Pat. No. 5,401,519 describes a low calorie composite sweetener by combining fructose with high intensity sweetener. The fructose particles are first covered with a non-reducing substance membrane and the high intensity sweetener is then deposited to the non-reducing substance membrane. The drawbacks of the disclosed composite sweetener include the requirement of additional bonding such as non-reducing substance membrane.
U.S. Pat. No. 6,703,057 discloses a granulated sugar product comprising a core and surface sugar layers where the core material is having higher density than the surface material. The surface material comprises substantially a second sugar, dextrins, sorbitol, mannitol, starch, cellulose, inulin, glycogen, xylitol, levoglucason or maltol (and ethyl derivative). It may also incorporate high intensity sweetener. The drawbacks of the disclosed sugar product include the requirements of another compound such as second sugar, dextrins, sorbito, mannitol, starch, cellulose, inulin, glycogen, xylitol, levoglucason, maltol or any other binding or bulking agent besides the sugar and high intensity sweetener.
U.S. Pat. No. 3,293,133 describes a process of imparting water insoluble colors to pharmaceutical solutions. According to described process the color solution is distributed onto sucrose particles to form a sucrose and coloring material blend. No adequate solutions are described to ensure even distribution of color solution on sucrose particles to produce material with maximal homogeneity. Mechanical stability of the blend obtained by described process will be insufficient.
U.S. Pat. No. 1,902,773 describes a process of protecting hygroscopic carbohydrate (fructose) with non-hygroscopic film and increasing the thickness of the film by additionally depositing non-hygroscopic carbohydrate crystals from saturated solution of non-hygroscopic carbohydrate (dextrose). Process employs a spray chamber where the hygroscopic granules are covered with film of non-hygroscopic compound by means of spraying while falling from top of the tower through spray zone where coating material is being sprayed. It has to be noted that such method of delivery of coating material cannot provide control of contact time of core particle with sprayed solution to ensure preparation of material with uniform characteristics.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a commercially valuable process for producing a low calorie composite sweetener comprising sugar and high intensity sweetener, particularly sweet glycosides of Stevia rebaudiana Bertoni plant (hereinafter steviol glycosides), and use thereof in various food products and beverages, which overcomes the disadvantages of the related art.
The invention, in part, pertains to the granulated sugar with a specific moisture content being distributed to form a layer with specific thickness on a vibrating surface. High intensity sweetener is dissolved in a solvent mixture comprising water and alcohol to make high concentration solution which was heated up to prevent crystal formation and was dispersed on the granulated sugar by means of an air-powered pneumatic method while maintaining the granulated sugar at intensive vibration conditions. The resulted product was dried to form a low calorie sugar-high intensity sweetener blend.
The sugar-steviol glycosides blends were applied in various foods and beverages as sweetener.
The processes developed in this invention can be used also for preparation of steviol glucosides' blends with other crystalline or granulated materials, particularly sweeteners, non-limiting examples of which will include fructose, palatinose, tagatose, sugar alcohols.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings are included to provide a further understanding of the invention. The drawings illustrate embodiments of the invention and together with the description serve to explain the principles of the embodiments of the invention.
FIG. 1 shows a sensory evaluation of Reb-A 97, Stevioside 98 and SG 95;
FIG. 2 shows a sensory evaluation of sugar-Reb-A 97, sugar-Stevioside 98 and sugar-SG 95 blends.
DETAILED DESCRIPTION OF THE INVENTION
Advantages of the present invention will become more 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.
The present description will use the terms and abbreviations in the sense defined as follows:
TSG content: Total Steviol Glycosides content determined by assay method described in FAO JECFA monographs 5 (2008).
High intensity sweeteners: sweeteners selected from the group consisting of stevioside, rebaudioside A, rebaudioside B, rebaudioside C, rebaudioside D, rebaudioside E, rebaudioside F, dulcoside A, dulcoside B, rubusoside, stevia, mogroside IV, siamenoside, mogroside V, Luo Han Guo sweetener, monatin and its salts (monatin SS, RR, RS, SR), glycyrrhizic acid and its salts, curculin, thaumatin, monellin, mabinlin, brazzein, hernandulcin, phyllodulcin, glycyphyllin, phloridzin, trilobtain, baiyunoside, osladin, polypodoside A, pterocaryoside A, pterocaryoside B, mukurozioside, phlomisoside I, periandrin I, abrusoside A, cyclocarioside I, and combinations thereof.
Steviol Glycosides: high intensity sweeteners selected from the group consisting of stevioside, rebaudioside A, rebaudioside B, rebaudioside C, rebaudioside D, rebaudioside E, rebaudioside F, dulcoside A, dulcoside B, and rubusoside and combinations thereof.
SG 95: mixture of Steviol Glycosides with TSG content above 95% (w/w).
Reb-A 97: high intensity sweetener with Rebaudioside A content above 97% (w/w).
Stevioside 98: high intensity sweetener with Stevioside content above 98% (w/w).
One aspect of the present invention provides a process for producing a low calorie composite sweetener comprising sugar and high intensity sweeteners. Briefly, the process comprises: adjusting the moisture content of granulate sugar to 3.0-4.0%, where the granulate sugar has a particle size of 800-1000 μm; distributing the moisturized granulate sugar on a vibrating surface to form a layer with thickness of 10-100 mm, preferably 25-35 mm; setting at vibration intensity from 1-2000 vibrations per minute (hereinafter vpm) preferably 1000-1300 vpm.
The step of adjusting moisture content of sugar granules can be accomplished by any means known to the art, for example, by contacting the sugar granules with humid air. Adjusting moisture content of sugar granules facilitates a rapid and even dispersion of the solution of high intensity sweetener on the sugar granules' surface and promotes stronger attachment between high intensity sweetener and sugar granule. The inventors of the present invention discovered that the range of the moisture content within the granulate sugar is critical for the process of producing low calorie composite sweetener and the quality of the composite sweetener produced. When the moisture content is lower than 3%, the bonding between granule surface and high intensity sweetener is not optimal; when the moisture content exceeds 4%, sugar granules tend to stick to each other, lowering the amount of high intensity sweetener bound to the sugar granules.
The preferred average particle size of granulated sugar promotes more optimal distribution of high intensity sweetener. Using material with particle size less than 800 μm at moisture levels and agitation mode employed in this invention cannot ensure sufficient mass exchange level of sugar granules and subsequent even distribution of high intensity sweetener on granules; whereas granules with size greater than 1000 μm do not provide surface area large enough hence heterogeneity of obtained blend will be higher.
Distribution of the sugar granules in a layer of specific thickness ensures the accessibility of all sugar granules to direct impact of dispersed solution of high intensity sweetener.
The vibrating surface can be a vibrating tray or vibrating conveyor. Maintaining the intensity of vibration while dispersing the solution of high intensity sweetener ensures that all available surfaces of sugar granules are able to be reached by the solution of high intensity sweetener therefore enhancing the quality uniformity of obtained sugar-high intensity sweetener blend. It also prevents the agglomeration and caking of sugar granules which often occurs in processes where other means of agitation or mixing is employed (e.g. mixing drums or blenders). Maintaining vibration intensity less than 1000 vpm or above 1300 vpm do not provide optimal mass exchange level for even distribution of high intensity sweetener.
Steviol glycoside preparation with TSG content of 95-100% (w/w) was dissolved in a solvent mixture comprising water and ethyl alcohol with ethyl alcohol content from 0.1-99.9% (v/v), preferably from 30-60% (v/v) to make steviol glycoside solution with 10-70% (w/w) preferably 30-60% (w/w) solids content.
The sugar to steviol glycoside dry weight ratio was from 50:1 to 300:1 (w/w), preferably 100:1 to 200:1 (w/w). The preferred choice of steviol glycoside was Reb-A 97, SG 95 and Stevioside 98.
The steviol glycoside aqueous alcoholic solution was heated up to 30-80° C. preferably 40-60° C. for prevention of crystal formation and was dispersed on the granulated sugar by means of pressure atomization method with pressure of compressed air at 0.01-1.0 MPa preferably 0.1-0.7 MPa over a period of 10-300 seconds, preferably 50-150 seconds while maintaining the intensity of vibration mentioned above.
Advantage of using the water-alcohol mixture for steviol glycoside dissolution compared to pure water is the increased dissolving capacity of such solvent. Most of the steviol glycosides in highly purified form have relatively low solubility in pure water. On the other hand alcohol reduces the sugar granules agglomeration possibility and tends to dry faster during the final drying step of the process. This in turn minimizes thermal degradation and color change of final product due to reduction of drying temperature and duration.
The increased temperature of the solution prevents premature crystallization of steviol glycoside, reduces the viscosity of concentrated solution and promotes partial evaporation of liquid during the dispersion of the concentrated solution onto sugar granules.
To eliminate the necessity of extensive drying process and prevent agglomeration of sugar granules a high concentration solution of high intensity sweetener is used instead of a dilute solution of high intensity sweetener.
Dispersing the solution of high intensity sweetener by means of pressure atomization allows a higher degree of dispersion even when a concentrated solution of high intensity sweetener is used. It promotes an even distribution of the high intensity sweetener on the sugar granules and minimizes agglomeration of sugar granules which often arises when the solution of high intensity sweetener is dispersed by direct addition of solution or by means of hydraulic dispersion. The amount of the solution of high intensity sweetener to be dispersed is critical depending upon the amount of the granulated sugar. In one embodiment, the amount of the solution of high intensity sweetener to be dispersed is 1-3% (w/w) of the granulated sugar.
The obtained product was dried over a period of 2-30 minutes, preferably 5-15 minutes, by means of a convective method in a drum-type drying apparatus set at a temperature of 50-85° C., preferably 60-70° C. until its moisture content was 0.01-0.5% preferably 0.05-0.1%.
The final step of drying is achievable by any drying processes known to the art.
The HPLC analysis of steviol glycosides and the obtained product was carried out using an Agilent Technologies 1200 Series (USA) equipped with Zorbax-NH 2 column (4.6×250 mm, 5 um) using acetonitrile-water 80:20, (v/v) mobile phase and UV detector at 210 nm as described in FAO JECFA Monographs 5 (2008).
The physico-chemical characteristics of obtained products were compared with a control sample produced by conventional method. It was shown that for all tested characteristics the samples prepared according to the process of this invention possess clear advantage compared with control sample.
The organoleptic test was carried out with 30 previously trained panel members. The test was carried out on water solutions of sugar-steviol glycoside blends with, Reb-A 97, Stevioside 98 and SG 95, as well as on same sweeteners used “as is”. It was observed that in all cases sugar-steviol glycoside blends have more acceptable taste profile compared to case when the same sweeteners are used “as is” without blending with other sweeteners. The sugar-Reb-A 97 blend had the lowest score for bitterness, while Stevioside 98 used “as is” was the most bitter compared to the other samples. For overall acceptability, sugar-Reb-A 97 blend had the highest score followed by SG 95, and Stevioside 98.
The obtained low-calorie composite sweetener can be favorably used for seasoning various food products (for instance, soy sauce, soy sauce powder, soy paste, soy paste powder, dressings, mayonnaise, vinegar, powdered vinegar, bakery products and confectioneries, frozen-desserts, meat products, fish-meat products, potato salad, bottled and canned foods, fruit and vegetables) in intact or mixed forms with other sweeteners, such as corn syrup, glucose, maltose, sucrose, lactose, aspartame, saccharin, sugar alcohols, organic and amino acids, flavors and/or coloring agents.
The products are favorably usable as low-calorie sweetener in exemplary applications including low-cariogenic food products such as confectioneries including chewing gum, chocolate, biscuits, cookies, toffee and candy. Additional applications include soft drinks such as coffee, cocoa, juice, carbonated drinks, sour milk beverage, yogurt drinks and alcoholic drinks, such as brandy, whisky, vodka and wine. In addition to the above-described uses, the sweeteners are usable for sweetening drugs and cosmetics.
The following examples illustrate preferred embodiments of the invention.
EXAMPLE 1
Sugar Based Sweetener with Reb-A 97
1490 g of granulated sugar with average particle size 800-1000 μm and moisture content adjusted to 3.9% was distributed to form a layer with thickness of 30 mm on a vibrating tray. 10.03 g Reb-A 97 (containing stevioside 0.31%, rebaudioside C 0.21%, rebaudioside A 98.56%, rebaudioside B 0.22%) was dissolved in 15.04 g of solvent mixture containing 4 volumes of water per 1 volume of ethyl alcohol to make rebaudioside A 40% (w/w) solution. The solution was heated up to 40° C. for prevention of crystal formation and was dispersed on the granulated sugar by means of an air-powered pneumatic method with pressure of compressed air at 0.1 MPa over a period of 100 seconds while maintaining the intensity of vibration at 1200 vpm. The granulated sugar was dried over a period of 10 minutes by means of a convective method in a drum-type drying apparatus set at a temperature of 65° C. until its moisture content was 0.08%.
The sweetener produced had homogenous and intact structure of crystal sugar and had identical taste profile as sucrose with sweetness power 3 times higher than sugar.
EXAMPLE 2
Sugar Based Sweetener with Stevioside 98
1488 g of granulated sugar with average particle size 800-1000 μm and moisture content adjusted to 3.4% was distributed to form a layer with thickness of 30 mm on a vibrating tray. 12.05 g stevioside 98 (containing stevioside 98.51%, rebaudioside C 0.31%, rebaudioside A 0.26%, steviolbioside 0.22%) was dissolved in 18.07 g of solvent mixture containing 4 volumes of water per 1 volume of ethyl alcohol to make stevioside 40% (w/w) solution. The solution was heated up to 40° C. for prevention of crystal formation and was dispersed on the granulated sugar by means of an air-powered pneumatic method with pressure of compressed air at 0.1 MPa over a period of 100 seconds while maintaining the intensity of vibration at 1200 vpm. The granulated sugar was dried over a period of 10 minutes by means of a convective method in a drum-type drying apparatus set at a temperature of 65° C. until its moisture content was 0.09%.
The sweetener produced had homogenous and intact structure of crystal sugar and had almost identical taste profile as sucrose with sweetness power 3 times higher than sugar.
EXAMPLE 3
Sugar Based Sweetener with SG 95
1488 g of granulated sugar with average particle size 800-1000 μm and moisture content adjusted to 3.4% was distributed to form a layer with thickness of 30 mm on a vibrating tray. 11.58 g SG 95 (containing rubusoside 0.21%, dulcoside A 0.39%, stevioside 30.31%, rebaudioside C 11.85%, rebaudioside A 51.56%, steviolbioside 0.23%, rebaudioside B 1.01%), was dissolved in 17.37 g of solvent mixture containing 4 volumes of water per 1 volume of ethyl alcohol to make 40% (w/w) solution. The solution was heated up to 40° C. for prevention of crystal formation and was dispersed on the granulated sugar by means of an air-powered pneumatic method with pressure of compressed air at 0.1 MPa over a period of 100 seconds while maintaining the intensity of vibration at 1200 vpm. The granulated sugar was dried over a period of 10 minutes by means of a convective method in a drum-type drying apparatus set at a temperature of 65° C. until its moisture content was 0.05%.
The sweetener produced had homogenous and intact structure of crystal sugar and had identical taste profile as sucrose with sweetness power 3 times higher than sugar.
EXAMPLE 4
Control Sugar Based Sweetener with Steviol Glycoside.
Three batches of sugar based sweeteners were made using Stevioside 98, Reb-A 97 and SG 95. 1490 g of granulated sugar was placed in rotary drum mixer. 10.03 g of Reb-A 97, 12.05 g of Stevioside 98 and 11.58 g of SG 95 were dissolved in enough amount of water to make saturated solutions at 40° C. The solutions were dispersed on the granulated sugar by means of an air-powered pneumatic method while rotating the drum mixer. The obtained mixtures were dried in a drum-type drying apparatus set at a temperature of 65° C. until moisture content less than 0.1%.
Produced sweeteners were compared with sweeteners prepared as per Examples 1, 2 and 3.
To evaluate the stratification of components due to mechanical impact the sweeteners were placed in air tight containers and placed on a vibrating platform set at 2000 vpm during 24 hours. Upon completion 3 samples were withdrawn from each container (top, middle bottom) and analyzed via HPLC to determine the consistency of steviol glycoside content in all levels. Each sample was evaluated also to determine its sweetness compared to intact sugar.
Additionally the sweeteners were analyzed on a 60 mesh test sieve to evaluate the amount of steviol glycoside “chipping off” from the surface of sugar granules. The results of evaluation are summarized in TABLE 1.
TABLE 1
Invention samples
Control samples
Reb-A
Stevioside
Reb-A
Stevioside
Parameter
97
98
SG 95
97
98
SG 95
Appearance
Same as granulated sugar
Similar to granulated sugar
Steviol glycoside content, % (w/w)
Top layer
0.64
0.78
0.75
0.38
0.36
0.52
Middle layer
0.66
0.79
0.75
0.54
0.61
0.65
Bottom layer
0.66
0.80
0.77
1.05
1.40
1.11
Sweetness, fold sugar sweetness
Top layer
3
3
3
2
2
2
Middle layer
3
3
3
2.5
2.5
2.5
Bottom layer
3
3
3
4
4.5
4
Steviol glycoside recovered after
1.1
1.3
0.9
21.2
25.6
15.3
sieve, % from applied amount
EXAMPLE 5
Low-calorie Orange Juice Drink
Orange concentrate (35%), citric acid (0.38%), ascorbic acid (0.05%), sodium benzoate (0.02%), orange red color (0.01%), orange flavor (0.20%), and low-calorie sweetener compositions (5.0%) prepared as per examples 1, 2 and 3 were blended and dissolved completely in the water (up to 100%) and pasteurized. The sensory evaluation of the samples is summarized in the TABLE 2. The data shows that best results were obtained for sweetener composition with Reb-A 97.
TABLE 2
Comments
Sample
Flavor
Aftertaste
Mouth feel
Stevioside
Sweet, rounded and balanced
Almost no any
Acceptable
98
Flavor, taste similar to
bitterness
sucrose
SG95
Sweet, rounded and balanced
No any
Full
Flavor, taste similar to
bitterness
sucrose
Reb-A 97
High quality of sweetness,
Clean, no
Quite full
pleasant, taste similar to
unpleasant
sucrose, balanced flavor
aftertaste
Similarly juices from other fruits, such as apple, lemon, apricot, cherry, pineapple, etc can be prepared.
Example 6
Low-calorie Carbonated Lemon-flavored Beverage
The formula for the beverage was as below:
Ingredients
Quantity
Sugar-steviol glycosides blend
43.3
kg
Citric acid
2.5
kg
Green tea extract
25.0
kg
Salt
0.3
kg
Lemon tincture
10.0
L
Juniper tincture
8.0
L
Sodium benzoate
0.17
Carbonated water
up to 1000 L
Sensory and physicochemical characteristics of the drink are presented in the TABLE 3.
The drinks with highly purified Rebaudioside A and Stevioside were superior with an excellent flavor and taste.
TABLE 3
Sugar-steviol glycosides blend
Characteristics
Stevioside 98
SG 95
Reb-A 97
Appearance
Transparent
Transparent
Transparent
liquid, free of
liquid, free of
liquid, free of
sediment and
sediment and
sediment and
foreign
foreign
foreign
impurities.
impurities.
impurities.
Color
From light
From light
From light
yellow up to
yellow up to
yellow up to
yellow
yellow
yellow
Taste
Sour-sweet,
Sour-sweet,
Sour-sweet,
expression of
no any
expression of
sweetness is
bitterness,
sweetness is
rapid. The
expression of
rapid.
taste is
sweetness is
satisfactory.
rapid.
EXAMPLE 7
Low-calorie Carbonated Drink
The formula for the beverage was as below:
Ingredients
Quantity, %
Cola flavor
0.340
Phosphoric acid (85%)
0.100
Sodium citrate
0.310
Sodium benzoate
0.018
Citric acid
0.018
Sugar-steviol glycosides blend
2.500
Carbonated water
to 100
The beverages prepared with different sweeteners were given to 30 judges for comparison.
TABLE 4 shows the results.
TABLE 4
Number of panelists (out of 30)
Characteristics
Stevioside 98
SG 95
Reb-A 97
Bitter taste
1
0
0
Astringent taste
1
0
0
Aftertaste
1
0
0
Quality of
27
(clean)
29
(clean)
30
(clean)
sweet taste
Overall
29
(satisfactory)
30
(satisfactory)
30
(satisfactory)
evaluation
The above results show that all the prepared beverages possess good organoleptic characteristics.
EXAMPLE 8
Chocolate
A composition containing 30 kg of cacao liquor, 11.5 kg of cacao butter, 14 kg of milk powder, 33.67 kg of sorbitol, 0.1 kg of salt, and 10.43 kg of sweetener prepared according to the EXAMPLES 1, 2 and 3, was kneaded sufficiently, and the mixture was then placed in a refiner to reduce its particle size for 24 hours. Thereafter, the content was transferred into a conche, 300 grams of lecithin was added, and the composition was kneaded at 50° C. for 48 hours. Then, the content was placed in a shaping apparatus, and solidified.
The products were low-cariogenic and low-calorie chocolate with excellent texture. Also, the organoleptic test carried out with 30 panelists revealed no lingering after-taste.
EXAMPLE 9
Ice-cream
1.50 kg of whole milk were heated to 45° C., and 300 grams of milk cream, 50 grams of tagatose, 28.75 grams of sorbitol, 6 grams of carrageenan as a stabilizer, 3 grams of polysorbate-80 as an emulsifier, and 112.25 gram of sweetener prepared according to the EXAMPLES 1, 2 or 3, were added into the milk and was stirred until the ingredients completely dissolved. The mixture then was pasteurized at a temperature of 80° C. for 25 seconds. The homogenization of the obtained mixture was carried out at a pressure of 800 bars and the samples were kept at a temperature of 4° C. for 24 hours to complete the aging process. Vanilla flavor (1.0% of the mixture weight) and coloring (0.025% of the mixture weight) are added into the mixture after aging. The mixture was then transferred to ice cream maker to produce ice cream automatically. Samples of ice creams produced were transferred to seal containers and were kept in the freezer at a temperature of −18° C.
Organoleptic test carried out with 30 panelists. The application of sweeteners does not affect the physicochemical properties of ice cream, as well as the overall attributes of color, smoothness, surface texture, air cell, vanilla aroma intensity, vanilla taste, chalkiness, iciness and melting rate.
EXAMPLE 10
Yogurt
In 5 kg of defatted milk, 333.2 grams of sweetener, prepared according to EXAMPLES 1, 2 and 3, were dissolved. After pasteurizing at 82° C. for 20 minutes, the milk was cooled to 40° C. A starter in amount of 150 grams was added and the mixture was incubated at 37° C. for 6 hours. Then, the fermented mass was maintained at 10-15° C. for 12 hours.
The product is a low-calorie and low-cariogenic yoghurt without foreign taste and odor.
EXAMPLE 11
Tooth Paste
A tooth paste was prepared by kneading a composition comprising of calcium phosphate, 45.0%; carboxymethylcellulose, 1.5%; carrageenan, 0.5%; glycerol, 18.0%; polyoxyethylene sorbitan mono-ester, 2.0%; beta-cyclodextrin, 1.5%; sodium laurylsarcosinate, 0.2%; flavoring, 1.0%; preservative, 0.1%; sweetener, obtained according to the EXAMPLE 1, 2 or 3, 16.6%; and water to 100%, by usual way. The product possesses good foaming and cleaning abilities with appropriate sweetness.
EXAMPLE 12
Soy Sauce
5.6 g of sweetener, obtained according to the EXAMPLE 1, 2 or 3 was added to 1000 mL of soy sauce and mixed homogenously. The products had an excellent taste and texture.
EXAMPLE 13
Bread
1 kg of wheat flour, 11.65 grams of fructooligosaccharide syrup, 80 grams of margarine, 20 grams of salt, 20 grams of yeasts, and 25.98 grams of sweetener, obtained according to the EXAMPLE 1, 2 or 3 were placed into the blender and mixed well. 600 mL of water was poured into the mixture and kneaded sufficiently. At the completion of the kneading process, the dough was shaped and raised for 30 to 45 minutes. The ready dough was placed in oven and baked for 45 minutes. Bread samples had creamy white color, and smooth texture.
EXAMPLE 14
Diet Cookies
Flour (50.0%), margarine (30.0%), whole milk (1.0%), salt (0.2%), baking powder (0.15%), vanillin (0.1%), sweetener, obtained according to the EXAMPLE 1, 2 or 3 (18.55%), were kneaded well in dough-mixing machine. After molding of the dough the cookies were baked at 200° C. for 15 minutes.
The product is a low-calorie diet cookie with excellent taste and appropriate sweetness.
EXAMPLE 15
Cake
123 g of hen eggs, 1.77 g of sugar, 345 g of sorbitol liquid, 2.0 g of sucrose fatty acid ester, 43.58 g of sweetener, obtained according to the EXAMPLE 1, 2 or 3 was mixed with 100 g of wheat flour and 200 g of water in order to prepare a cake according to a conventional method. The product had an excellent taste with an optimal sweet flavor.
It is to be understood that the foregoing descriptions and specific embodiments shown herein are merely illustrative of the best mode of the invention and the principles thereof, and that modifications and additions may be easily made by those skilled in the art without departing for the spirit and scope of the invention, which is therefore understood to be limited only by the scope of the appended claims. | The invention provides a process for producing a low calorie composite sweetener as a sugar alternative. The invention further provides a low calorie composite sweetener that can be used in many products. The low calorie composite sweetener is useful as non-caloric sweeteners in edible and chewable compositions such as any beverages, confectionaries, bakeries, cookies, chewing gums, and alike. | 0 |
FIELD OF THE INVENTION
[0001] The disclosure relates in general to the removal of contaminants from hydrocarbon liquids and gases. In certain embodiments, the disclosure relates to the use of a copper-based sorbent to remove heterocyclic sulfides from hydrocarbon streams. In certain embodiments, the disclosure relates to the use of a sorbent comprising supported metallic copper to remove heterocyclic sulfides from hydrocarbon streams.
BACKGROUND OF THE INVENTION
[0002] The removal of sulfur compounds from gas and liquid streams is an important process in the hydrocarbon industry. Hydrogen sulfide, a common sulfur-based contaminant, can be removed by supported copper oxide adsorbents known in the prior art. Other sulfur-containing contaminants are, however, more difficult to remove. For example, heterocyclic sulfides, such as thiophene, cannot be effectively removed by prior art copper oxide adsorbents. Nor can heterocyclic sulfides be removed by distillation because they co-boil with desirable hydrocarbons, such as benzene.
[0003] Modified zeolites and metal oxides, such as alumina, are known in the prior art to remove heterocyclic sulfides by adsorption. However, in the case of acidic zeolites, the acidity of the zeolite support results in discoloration of the main stream and the shifting of the boiling range of the feed hydrocarbon fraction. In addition, silver exchanged zeolites have low loading capacities and deactivate easily due to changes in the oxidation state of the silver active sites. Finally, Cu + exchanged zeolites have poor long term stability.
[0004] Copper-based adsorbents, including those derived from copper carbonate, are widely used in the hydrocarbon industry to remove contaminants by chemisorption. Copper-based adsorbents, however, are not effective in heterocyclic removal. Accordingly, it would be an advance in the state of the art to provide a copper-based material, and method of using same, for removing heterocyclic sulfur compounds from a hydrocarbon stream via chemi sorption.
SUMMARY OF THE INVENTION
[0005] A method of removing heterocyclic sulfide impurities from a fluid stream is presented. The method comprises contacting the fluid stream with a sorbent comprising metallic copper.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0006] The invention is described in preferred embodiments in the following description. Reference throughout this specification to “one embodiment,” “an embodiment,” or similar language means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, appearances of the phrases “in one embodiment,” “in an embodiment,” and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment.
[0007] The terms sorbent, adsorbent, and absorbent as used herein refer to the ability of a material to take in or soak up liquid or gas components on the surface thereof or to assimilate such components into the body thereof, whether by chemisorption (i.e., scavenging) or filtering (by way of a molecular sieve).
[0008] Applicants' sorbent comprises an active copper phase disposed within a support material. In one embodiment, the active copper phase comprises metallic copper. The metallic copper is capable of reacting with the sulfur atom on the heterocyclic sulfide, such as thiophene (1), at elevated temperatures, thereby scavenging the sulfide from a hydrocarbon stream.
[0000]
[0009] In one embodiment, substantially all copper in Applicants sorbent is at an oxidation level of +0. In this embodiment, the active copper phase comprises no or substantially no cuprous oxide (Cu 2 O), and no or substantially no cupric oxide (CuO).
[0010] In various embodiments, the support material is a metal oxide selected from the group consisting of alumina, silica, silica-aluminas, silicates, aluminates, silico-aluminates such as zeolites, titania, zirconia, hematite, ceria, magnesium oxide, and tungsten oxide. In one embodiment, the support material is alumina. In some embodiments, the support material is carbon or activated carbon. In certain embodiments, Applicants' sorbent does not comprise a binder.
[0011] In various embodiments, the alumina support material is present in the form of transition alumina, which comprises a mixture of poorly crystalline alumina phases such as “rho,” “chi” and “pseudo gamma” aluminas which are capable of quick rehydration and can retain substantial amounts of water in a reactive form. An aluminum hydroxide Al(OH) 3 , such as gibbsite, is a source for preparation of transition alumina. The prior art industrial process for production of transition alumina includes milling gibbsite to 1-20 microns particle size followed by flash calcination for a short contact time as described in the patent literature such as in U.S. Pat. No. 2,915,365. Amorphous aluminum hydroxide and other naturally found mineral crystalline hydroxides, e.g., Bayerite and Nordstrandite or monoxide hydroxides, AlOOH, such as Boehmite and Diaspore can be also used as a source of transition alumina. In certain embodiments, the BET surface area of this transition alumina material is about 300 m 2 /g and the average pore diameter is about 30 angstroms as determined by nitrogen adsorption, resulting in a porous sorbent.
[0012] In various embodiments, a solid oxysalt of a transition metal is used as a starting component of the sorbent. “Oxysalt,” by definition, refers to any salt of an oxyacid. Sometimes this definition is broadened to “a salt containing oxygen as well as a given anion.” FeOCl, for example, is regarded as an oxysalt according this definition.
[0013] In certain embodiments, the oxysalt comprises one or more copper carbonates. Basic copper carbonates, such as Cu 2 CO 3 (OH) 2 , can be produced by precipitation of copper salts, such as Cu(NO) 3 , CuSO 4 and CuCl 2 , with sodium carbonate. In one embodiment, a synthetic form of malachite, a basic copper carbonate, produced by Phibro Tech, Ridgefield Park, N.J., is used as a component of the sorbent.
[0014] Depending on the conditions used, and especially on washing the resulting precipitate, the final material may contain some residual product from the precipitation process. In the case of the CuCl 2 raw material, sodium chloride is a side product of the precipitation process. It has been determined that a commercially available basic copper carbonate comprising both residual chloride and sodium, exhibited lower stability towards heating and improved resistance towards reduction than other commercial basic copper carbonates that were practically chloride-free.
[0015] In one embodiment, the size of the basic copper carbonate particles is approximately in the range of that of the transition alumina, namely 1-20 microns. In other embodiments, the sorbent comprises the oxysalt Azurite, Cu 3 (CO 3 ) 2 (OH) 2 . In other embodiments, the sorbent comprises an oxysalt of copper, nickel, iron, manganese, cobalt, zinc or a mixture thereof.
[0016] In one embodiment, the sorbent is produced by conodulizing basic copper carbonate with alumina followed by curing and activation. In various embodiments, the nodulizing, or agglomeration, is performed in a pan or a drum. The materials are agitated by the oscillating or rotating motion of the nodulizer while spraying with water to form beads. In one embodiment, the beads are cured at about 60° C. and dried in a moving bed activator at a temperature at or below about 175° C. In other embodiments, the sorbent beads are formed by extrusion.
[0017] In one embodiment, the sorbent beads are calcinated by heating to between about 350° C. to about 450° C. The heat decomposes the copper carbonate to produce cupric oxide (CuO). In one embodiment, the copper carbonate is fully decomposed to CuO (i.e., there is no or substantially no copper carbonate in the sorbent bead after calcination).
[0018] The cupric oxide-containing sorbent is exposed to a reducing environment to form metallic copper. In various embodiments, the reducing environment comprises hydrogen gas (H 2 ), carbon monoxide gas (CO), methane (CH 4 ), or a combination thereof. In various embodiments, the reduction occurs at between about 100° C. to about 210° C., depending on the reducing agent and the exposure time. In various embodiments, the reduction occurs at between about 120° C. to about 190° C. The cupric oxide, with an oxidation state of +2, is first reduced to cuprous oxide, with an oxidation state of +1, and finally to metallic copper, with an oxidation state of +0. In certain embodiments, the conversion of CuO to metallic copper is complete, leaving no or substantially no CuO or Cu 2 O in the final sorbent.
[0019] In various embodiments, and depending on the application, the sorbent comprises about 5 mass percent copper to about 95 mass percent copper, calculated as CuO on a volatile-free basis. In one embodiment, the sorbent comprises between about 25 mass percent and about 50 mass percent copper, calculated as CuO on a volatile-free basis. In one embodiment, the sorbent comprises about 32 mass percent copper, calculated as CuO on a volatile-free basis. In one embodiment, the sorbent comprises about 68 mass percent copper, calculated as CuO on a volatile-free basis.
[0020] In certain embodiments, the sorbent has a diameter (for spherical beads) or maximum width (for irregular shaped beads) of about 1 mm to about 10 mm. In certain embodiments, the sorbent has a diameter or maximum width of about 2 mm to about 6 mm.
[0021] In various embodiments, the sorbent is porous (i.e., have a plurality of pores and voids extending therethrough).
[0022] The metallic copper-containing sorbent is placed in contact with a flowing hydrocarbon liquid or gas stream, which contains heterocyclic sulfides, at a temperature of about 110° C. to about 200° C.
[0023] The following Example is presented to further illustrate to persons skilled in the art how to make and use the invention. This Example is not intended as a limitation, however, upon the scope of Applicant's invention.
Example
[0024] A mixture of a copper oxysalt and a support material is provided. In one embodiment, the copper oxysalt is basic copper carbonate, Cu 2 (OH) 2 CO 3 and the support material is alumina powder capable of rehydration. In different embodiments, the copper content of the mixture, calculated as CuO on a volatile-free basis, is between about 5 mass percent and about 95 mass percent.
[0025] Green sorbent beads are formed from the mixture. As used herein, “green sorbent beads” refer to beads containing the copper oxysalt before reduction to metallic copper and “activated sorbent beads” refer to beads where at least a portion of the copper oxysalt has been fully reduced to metallic copper. In one embodiment, the beads are formed by nodulizing the mixture in a rotating pan nodulizer while spraying with a liquid. In one embodiment, the liquid comprises water.
[0026] In another embodiment, the green sorbent beads are formed by agglomeration. In yet another embodiment, the green sorbent beads are formed by extrusion. Those skilled in the art will appreciate that other methods may be performed to form regular- or irregular-shaped beads that fall within the scope of Applicants' invention.
[0027] The green sorbent beads are cured and dried. In one embodiment, the curing occurs at about 60° C. In one embodiment, the beads are dried in a moving bed activator at temperatures at or below 175° C.
[0028] The copper in the sorbent beads is decomposed to CuO. In one embodiment, the decomposition occurs in an atmosphere of helium, air, nitrogen gas, or a combination thereof. In one embodiment, the decomposition occurs at about 400° C. In certain embodiments, the decomposition to CuO in the sorbent beads is complete (i.e., all or substantially all copper carbonate is decomposed to CuO).
[0029] The CuO (oxidation level +2) in the sorbent beads is reduced to metallic copper (Cu, oxidation level +0) by exposure to a reducing environment. In different embodiments, the reducing environment comprises an atmosphere of hydrogen, carbon monoxide, natural gas, methane, or a combination thereof. In various embodiments, the reduction takes place at a temperature of about 120° C. to about 190° C. In certain embodiments, the sorbent comprises no CuO (i.e., all or substantially all CuO is reduced to Cu). In certain embodiments, the reduction is monitored by x-ray detection or color sensors.
[0030] In certain embodiments, the cupric oxide (CuO) is reduced to cuprous oxide (Cu 2 O) and finally to metallic copper. In certain embodiments, the sorbent comprises no Cu 2 O (i.e., all or substantially all Cu 2 O is reduced to Cu). In certain embodiments, the sorbent comprises no copper oxide (i.e., all or substantially all the copper in the copper carbonate is reduced to metallic copper). In certain embodiments, the copper carbonate is directly reduced to metallic copper without being converted to an intermediate oxide (i.e., CuO, Cu 2 O) by reaction (1).
[0000] Cu 2 (OH) 2 CO 3 +2H 2 →2Cu+3H 2 O+CO 2 (1)
[0031] The sorbent is placed in a hydrocarbon fluid (i.e., liquid or gas) stream containing sulfide impurities. In one embodiment, the hydrocarbon stream comprises heterocyclic sulfide impurities, such as without limitation thiophene. In one embodiment, the hydrocarbon stream comprises heterocyclic sulfides and hydrogen sulfide. In one embodiment, the hydrocarbon stream comprises an aromatic compound, such as without limitation benzene. In one embodiment, the hydrocarbon stream comprises an aliphatic compound, such as without limitation heptane. In one embodiment, the temperature of the stream is between about 110° C. to about 200° C. In one embodiment, the temperature of the stream is about 150° C. In one embodiment, the temperature of the stream is about 175° C. In one embodiment, the temperature of the stream is about 200° C.
[0032] The described features, structures, or characteristics of the invention may be combined in any suitable manner in one or more embodiments. In the above description, numerous specific details are recited to provide a thorough understanding of embodiments of the invention. One skilled in the relevant art will recognize, however, that the invention may be practiced without one or more of the specific details, or with other methods, components, materials, and an forth. In other instances, well-known structures, materials, or operations are not shown or described in detail to avoid obscuring aspects of the invention. In other words, the present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described implementations are to be considered in all respects only as illustrative and not restrictive. The scope of the invention should, therefore, be determined not with reference to the above description, but instead should be determined with reference to the pending claims along with their full scope or equivalents, and all changes which come within the meaning and range of equivalency of the claims are to be embraced within their full scope. | A method of removing heterocyclic sulfide impurities from a fluid stream is presented. The method comprised contacting the fluid stream with a sorbent comprising metallic copper. | 2 |
CROSS-REFERENCES TO RELATED APPLICATIONS
This is an improvement on copending application Ser. No. 442,356 entitled "DART GAME", filed Nov. 17, 1982 assigned to the assignee of the present application.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates in general to dart games and in particular to a computerized dart game which has a double bullseye so that the dart board of the game duplicates the official tournament dart boards which are used as the official bristol dart board of the British darts organization.
2. Description of the Prior Art
Electronic dart games are known such as illustrated in Pat. Nos. 4,057,251, 1,199,564, 2,808,266, 2,818,259, 3,309,091 and 3,454,276. In these patents, darts impinge upon a board so as to cause segments of the board to close a switch and wherein such switches are connected to components for registering, totalling and displaying the score of the player. However, it has not been possible with prior art electronic dart games to have a double bullseye as is utilized in the official dart game.
SUMMARY OF THE INVENTION
The present invention provides a double bullseye for an electronic dart game wherein the outer bullseye comprises a concentric segment which moves in a cylindrical holder and is keyed to the holder so that it cannot rotate and an inner bullseye of generally cylindrical shape which is guided by the outer bullseye and which has a shoulder which engages the outer bullseye to limit its outward motion. The inner bullseye is free to rotate relative to the outer bullseye and is formed with switch engaging feet so as to close a disc-shaped switch contact so as to record a dart hit in the inner bullseye.
Other objects, features and advantages of the invention will be readily apparent from the following description of certain preferred embodiments thereof taken in conjunction with the accompanying drawings although variations and modifications may be effected without departing from the spirit and scope of the novel concepts of the disclosure and in which:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the computerized dart game of the invention;
FIG. 2 is a front plan view of the dart board;
FIG. 3 is a detail enlarged section view of the invention;
FIG. 4 is a plan view illustrating the pressure sensitive switch;
FIG. 5 is an enlarged view of the bullseye member;
FIG. 6 is a perspective exploded view of the bullseye members; and
FIG. 7 is a sectional view of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 illustrates a dart game 10 of the invention which includes a base 11 and an upwardly extending portion 15 which carries a dart board 12. A control panel is mounted on the front portion 20 of the extending portion 15 and includes a game selector switch 13 which has a plurality of different segments which allow different games to be selected. The games can be selected such as 301, 501, high score, double in, double out, scram and Shang-hai. These are various games that vary the condition and scoring of the dart game and can be selected by the players as desired. A coin slot 24 is mounted on the side of the base 11 and a portion of 24 which also includes a coin rejector with a cancel switch at 24 and coin return switch also on 24 and coin return slots 26 and 27. The control panel also includes a removed dart indicator 25 and a bust indicator 19. A temporary score indicator 14 is mounted on the face plate as well as a round indicator 18. A score indicator 16 indicates the scores for the individual players up to four players. An indicator 21 indicates when darts are to be thrown and the game over indicator 22 is mounted below it. A push switch 17 is provided.
In prior art, electronic scoring dart games, it has not been possible to provide a double bullseye such as is utilized in the official dart game and the present invention provides a double bullseye so that the present game is identical to the official darts target.
In the present invention, regulation weight darts are thrown at the target which have plastic tip 71 as illustrated in FIG. 7 rather than steel tips which render the game safer since the plastic tips 71 are less likely to cause injury to a person if they accidentally hit him. FIG. 2 is a plan view of the target of the invention which comprises a plurality of equally spaced radial dart deflecting ribs 43a through 43t and a number of concentric ribs 33, 36, 37, 38 and 39 so as to divide the target into different scoring areas.
Double segments 44a through 44t are mounted between the rings 33 and 36. Larger scoring segments 45a through 45t are mounted between the rings 36 and 37, smaller triple score segments 46a through 46t are mounted between the rings 37 and 38. Pie-shaped segments 47a through 47t are mounted between the rings 38 and 39 and the double bullseye comprising an outer annular target portion 41 and an inner cylindrical portion 42 are mounted within the ring 39 and comprise the inventive concept of the present invention. In the prior art, only a single inner target segment provided the bullseye and, thus, the prior art electronic scoring dart games did not conform to the official dart board. The present invention provides both the outer bullseye 41 and the inner bullseye 42. It is to be realized, of course, that these two segments score differently in the official game and the official scoring is accomplished in the present invention.
FIG. 6 illustrates an exploded view of the inner and outer bullseye members 41 and 42. The outer annular bullseye 41 is cylindrical-shaped and is formed with a keyway 73 into which a key 74 of the ring 39 extends as shown in FIG. 5 so as to prevent the bullseye portion 41 from rotating relative to the ring 39 but allowing it to move in and out as it is struck by a dart to provide scoring. A ring 84 is provided to deflect darts into the scoring openings 72 of the members 41 or 42 as illustrated in FIG. 7 and the rear portion of the member 41 is provided with a number of feet 66 as, for example, four feet which are adapted to engage switch portions 76, 77, 78 and 79 when a dart 71 engages the member 41 as shown in FIG. 7. The switch segments 76, 77, 78 and 79 are formed on the pressure sensitive switch 57 illustrated in FIG. 4 and thus a circuit is closed whenever a dart engages an opening 72 due to the closing by feet 66 of any of the switch contacts 76, 77, 78 and 79.
The inner bullseye portion 42 is also illustrated in FIGS. 6 and 7 and has a smaller cylindrical portion 85 formed with openings therein for receiving the dart 71. A larger cylindrical portion 86 is formed on the rear portion of the member 42 and the shoulder 87 thus formed can engage an inner shoulder 88 formed on the outer bullseye member 41 as illustrated in FIG. 7. In FIG. 7, member 41 is moved to the right to close its switches, but member 42 is not moved by member 41 to close its switches. Suitable clearances are formed between the shoulder 87 and the shoulder 88 such that when a dart engages the member 41 to close the switches 76, 77, 78 and 79, the shoulder 87 does not engage the member 88 to cause feet 67 formed on the inner bullseye 42 to close an associated concentric switch 81 of the pressure switch 57. On the other hand, if a dart engages the inner bullseye member 42, the feet 67 will close the concentric switch 81 and, thus, an inner bullseye score will be recorded by the scoring mechanism of the electronic dart game.
FIG. 5 is a plan cutaway view of the inner bullseye illustrating the outer bullseye and the inner bullseye 42.
FIG. 3 is a cutaway sectional view of the score board illustrating the mounting means for the score board from the top portion 15 and the front portion of the case of the game. The dart board 12 is mounted to a wooden front plate 20a, by bolts 32 as illustrated. A plastic decorative panel 20 is mounted to the wood cabinet. The pressure sensitive switch 57 has a rubber backing 58 and is mounted to a support board 51 which is mounted by bolts and thumb screws 53 to plate 20a with standoff 56 providing the proper spacing and clearance. Rubber backing 58 provides a soft protective barrier between the feet on segments, e.g. 44, 45f etc. and the switch 57. Thus, by removing the thumb screw 53 from the bolt 52 the board 51 and the members 57 and 58 can be withdrawn from the housing of the game and broken dart points can be removed from the score board.
As shown in FIG. 3, the segments 44 have feet 61 for closing associated switch areas in the switch 57 and the segments 45 have associated feet 62 for closing associated switch segments in the switch 57. The segments 46 have feet 63 for closing associated switch segments and the segments 47 have feet 64 for closing associated switch segments.
It is seen that the present invention provides an inner bullseye 42 so as to allow different scoring in the inner bullseye portion 42 and the outer bullseye portion 41 which is identical to the official darts game and, thus, the electronic dart game of the present invention can be used for official dart contests.
It is to be realized, of course, as described in the above reference copending application, that the various contacts of switch 57 are connected to electronic scoring mechanism which actuates and indicates the individual scores in the scoring indicator 16 for the individual players. In a particular embodiment, two separate micro-computers were utilized, one to scan the switch segments 57 and the other to control the various indicators and totallizers of the invention. One of these micro-computers was an Intel type 8748 and the second micro-computer was an Intel type 8031. For the detail circuitry and operation of the micro-computers and the scoring reference may be made to the above referenced copending application. Such structure is well known to those skilled in the art and the inventive concept of the present invention is to the inner and outer bullseye structures 41 and 42.
Although the invention has been described with respect to preferred embodiments, it is not to be so limited as changes and modifications may be made therein which are within the full intended scope as defined by the appended claims. | A double bullseye for a dart game which can be electronically scored when hit by a dart wherein the outer bullseye comprises a concentric moveable segment and the inner bullseye comprises a cylindrical member received in a central guide opening of the outer segment and wherein the inner segment is formed with a shoulder which limits the outward motion of the inner bullseye. Both the inner and the outer bullseyes are formed with feet portions which are engageable with electronic pressure sensitive switches so as to record hits by a dart in the respective segments. | 5 |
This is a division of application Ser. No. 08/008,169 filed on Jan. 25, 1993.
FIELD OF THE INVENTION
The present invention relates to the disposal of rubber products, more specifically to recycling of rubber products, and still more specifically to reinforced rubber products.
BACKGROUND OF THE INVENTION
The present invention is directed to the disposal of scrap or used rubber products, and more specifically to reinforced rubber products such as automobile and truck tires, conveyor belts and the like and still more particularly to a method and apparatus utilizing ozone (O 3 ) to destroy or disintegrate the rubber and rubber products and separate the rubber from the reinforcement materials.
The disposal of various used or spent rubber products, especially reinforced rubber products such as tires, conveyor belts, and the like, has long been recognized as a major environmental problem. The recycling of solid waste materials, particularly reclaimable, useful materials, such as tires from automobiles, trucks and tractors and such is of great importance from the standpoint of conservation of resources as well as pollution abatement.
It has been estimated that over 280 million spent rubber tires are discarded every year in the United States and over two billion scrap tires litter the landscape, dumped in land-fills or oceans off-shore. Most of the discarded tires are located in open dumps where they collect rain or run-off water and serve as fertile breeding grounds for mosquitoes, rats and other pests.
In earlier years, these scrap tires were burnt in open pits or furnaces causing enormous air pollution problems in terms of the noxious gases produced during combustion. A common disposal method currently in use is burying them in land-fills but this method has its own attendant problems in that it fills up valuable space fast and more additional sites need to be found. Furthermore, the tires when buried whole under eight feet or so of soil or solid waste, refuse to stay buried and float to the top. Another method for the disposal of spent tires consists of cutting up or shredding the tires prior to dumping them in land-fills. However, cutting equipment to dispose of the tires efficiently is costly and requires frequent replacement or repairing of the cutting tools or surfaces, especially if the tires are reinforced with steel wires and fiber mesh. More recently, scrap tires are being considered as a source of fuel and are being used in large incinerators to extract energy therefrom. See M. W. Mayo et al., "Processing Scrap Tires For Multiple Markets," Solid Waste & Power, March/April, 1992.
In recent times, automotive tires have been reinforced with fiber and steel or other metal belts or cords for greater durability and stability. With the advent of fabric and metal reinforcement of tires, and the reduction of the tire recapping industry because of the difficulty in recapping reinforced tires, the presence of steel and other materials poses additional difficulties in the disposal of these materials. Efforts have been directed to removing the reinforcement materials from the rubber prior to disposal but the disposal of the reinforcement material in and of itself poses an additional pollution problem.
Methods of alleviating some of these disposal problems include using tire sections for decorative purposes, cutting of the rubber from the reinforcement materials, shredding the tires, cooling the tire pieces to the brittling temperature of rubber and pulverizing the rubber using sledge or drop hammers. The pulverized rubber is then used for various purposes such as asphalt paving, soles for shoes, to line land-fills and the like.
These prior art methods for the disposal and/or recycling of scrap or discarded tires are exemplified by U.S. Pat. Nos. 4,142,688 issued Mar. 6, 1979; 4,180,004 issued Dec. 25, 1979 to A. O. Johnson; 4,726,530 issued Feb. 23, 1988 to D. Miller et al; 4,757,949 issued Jul. 19, 1988 to N. P. Horton; 4,839,151 issued Jun. 13, 1989 to F. Apffel; 4,840,316 issued Jun. 20, 1989 to R. L. Barclay; 5,057,189 issued Oct. 15, 1991 to F. Apffel; 5,097,905 issued Mar. 10, 1992 to K. N. Murray; and 5,115,983 issued May 26, 1992 to D. Rutherford, Sr. In addition, efforts were also being made in other countries to address the pollution problem caused by scrap tires. These efforts are exemplified by U.S.S.R. Author Certificates Nos. 1685721 dated 05.06.89 and 1698075 dated 12.02.90; and British Patent Specification No. 1438278 by J. R. Lanning, published Jun. 3, 1976.
While these prior art approaches have served to reduce the volume of discarded tires and tire materials, the energy efficiency, cost-effectiveness and environmental efficacy of these prior efforts leave a great deal to be desired. Consideration must also be given to the capability of such approaches being readily portable for in situ applications, as well as the capability to be easily scaled up for large production-type facilities. While the prior systems may be environmentally acceptable that they may be located at sites remote from residential areas, they are not energy-efficient or cost effective in that the discarded tires need to be transported to the remote location. The processes involved are also energy-intensive which is a disadvantage in these times of a need for energy conservation. Some methods for tire disposal or treatment such as the recovery process disclosed in the Apffel patent '151 involves the pyrolysis of the tire consumes enormous amounts of energy. Similarly, the cold crushing method described by Lanning (Br. Pat. '278) requires the deep cooling of the tire, using liquid nitrogen, to its brittling temperature. Methods requiring either heating and cooling consume significant amounts of energy and make the operation prohibitively expensive. Therefore, there is a need in the art for a technique by which reinforced rubber products, such as tires, can be recycled, and which is energy-efficient, cost-effective and responsive to environmental concerns.
It has long been recognized that rubber is subject to oxygen and ozone degradation. In the manufacture of tires, for example, substantial efforts have been directed to eliminating or reducing ozone degradation by the addition of anti-oxidants to rubber formulations. These efforts are exemplified by U.S. Pat. Nos. 5,023,227 issued Jun. 11, 1991 to L. R. Evans et al; 5,025,066 issued Jun. 18, 1991 to J. L. De Rudder et al; 5,088,537 issued Feb. 18, 1992 to M. Kan; and 5,120,844 issued Jun. 9, 1992 to E. L. Wheeler et al. The time required for tire degradation with the ozone content in the atmosphere is much too long (more than one year) to be utilized for practical purposes. Even when the ozone concentrations are increased to environmentally acceptable levels, the degradation times of more than one week are still too long for practical applications. (Natural Rubber Science and Technology," Ed. A. D. Roberts, Oxford University Press, 1988). It has also been known that the relationship of the rate of rubber degradation to the ozone concentration is not linear even at low ozone concentration levels, especially in the presence of antioxidants. Beyond a certain threshold level of ozone concentration, the effect of the antioxidant is also suppressed, making this nonlinear relationship even more complex. For certain antioxidants, this threshold level is near 0.1% ozone. (M. Braden & A. N. Gent, J. Appl. Poly. Sci., 6, 449(1962).
Thus, while it has been widely recognized that the effects of ozone on tires needed to be addressed in the manufacture of tires, it has not been previously appreciated that this same tire degrading environment can be effective in the decomposition of tires for recycling purposes. It would be desirable, therefore, to have a method for the disposal of reinforced tires which does not require burning, cooling or shredding of the tire.
It is an object of the present invention, therefore, to provide a technique for the disposal of used or spent reinforced or unreinforced rubber products which is energy-efficient, cost-effective and environmentally responsible.
A further object of the invention is to provide a method for recycling reinforced rubber products.
Another object of the invention is to provide a readily portable apparatus for in situ disposal of used or spent reinforced rubber products.
Yet another object of the invention is to provide a method and apparatus for removing steel mesh or belts from steel-belted tires without destruction of the steel mesh or strands.
A further object of the invention is to provide a method and apparatus for the disposal of reinforced rubber products without significant heating or cooling of the rubber product.
A further object of the invention is to provide a method and apparatus for the disposal of used or spent reinforced or unreinforced rubber tires by placing the tires in an ozone atmosphere, either at room temperature or at lower or higher temperatures, and in a strained state causing rapid breakdown of the rubber.
Another object of the invention is to provide a method and apparatus for disposing of reinforced rubber tires which can be readily adapted for individual or continuous operation and can accommodate different tire sizes.
Additional objects, advantages and novel features of the invention will be set forth in part in the description which follows and the drawings incorporated hereinto, and in part will become apparent to those skilled in the art upon examination of the following or may be learned by practice of the invention. The objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims.
SUMMARY OF THE INVENTION
To achieve the foregoing and other objects and in accordance with the purpose and principles of the present invention as embodied and broadly described herein, the present invention is directed to an apparatus and method for the recovery of rubber, metal and fiber products from scrap or spent rubber tires and other rubber products. The present invention provides a technique which utilizes a process wherein the discarded reinforced or unreinforced rubber products are exposed to ozone (O 3 ). The invention achieves the decomposition of spent or used tires without significant heating or cooling of the rubber tires, by placing discarded tires in a chamber containing ozone (0.01 to 30%) and by applying a pressure or loading force of at least 0.5 Kg/cm 2 or higher on the tires for deforming them. The relative strain level on the tire is about 3% or higher. The process may be carried out at any temperature although from a practical standpoint, the process is conveniently carried out at room or ambient temperature. The deformation process facilitates the breakdown of the rubber. The reinforcement materials released when the rubber breaks down may be readily removed for disposal or reuse. The remaining rubber pieces or powder are collected for recycling and any remaining ozone is recirculated or catalytically destroyed. Thus, the technique of this invention is simple in operation, energy efficient, cost-effective, and responsive to environmental concerns.
Basically the invention involves the disposal of used or spent reinforced rubber products, such as tires, wherein the product is placed in an ozone containing environment at room or ambient temperature, and is subjected to mechanical, static or other forms of deformation and strain on the rubber. Ozone concentrations may vary from about 0.01 to about 30% by weight or volume and preferably in the range of about 0.5 to about 10%. Deformation or strain levels may be varied from about 3 to 30%, preferably about 5 to 15%. A mechanical load of about 0.5 Kg/cm 2 produces a strain level of about 10%. By way of example, with an air/ozone mixture of 0.5% ozone (O 3 ) by volume and with a strain level near 0.5 Kg/cm 2 , a conventional reinforced automobile tire can be disposed of in less than fifteen minutes. The invention can also be readily adapted for single or continuous tire disposal and can be readily transported.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are incorporated into and for a part of the disclosure, illustrate embodiments of the apparatus for carrying out the invention and, together with the written description, serve to explain the principles of the invention.
FIG. 1 is a schematic illustration of an embodiment of an apparatus made in accordance with the invention for carrying out a continuous process operation; and
FIG. 2 is a schematic illustration of an embodiment of a portable apparatus for carrying out the process for single or several tires as a batch process.
DETAILED DESCRIPTION OF THE INVENTION
The present invention is directed to the disposal or recycling of used or spent rubber products, especially reinforced rubber tires or other products, and is particularly applicable for disposing of discarded or spent rubber tires reinforced with belts of fabric or steel, without destroying the material of the belts, while being energy efficient, cost-effective and environmentally safe. The apparatus is readily transportable, can be utilized for single or continuous operation, and thus can be easily transported to tire locations, such as dumps, land-fills, and depositories, without creating an environmentally polluting situation.
One purpose of the invention is to achieve the separation of, for example, the steel products from the rubber without mechanical cutting or abrasion of the whole product, or without significant heating or cooling of the rubber tire or other product, utilizing a process which may, conveniently, be carried out at room or ambient temperature. For destruction of the whole product (a steel-belted tire, for example) without cutting or sanding down the rubber tread, the product is placed in an ozone-containing gas or air mixture and then is to subjected to mechanical loading and deformation for providing a strained state of the rubber. After breakdown of the rubber and the disintegration of the whole product, any remaining ozone is withdrawn for recirculation or catalytically destroyed, and the steel elements are separated from the rubber fragments, particles or powder as the case may be. Ozone may be generated using known methods, with air or oxygen as the starting material.
In the method of this invention involving rubber destruction using ozone, the strained state of the rubber increases the rate of rubber disintegration. The processing at room or ambient temperature significantly decreases energy consumption and risks of fire hazards. To achieve the disintegration of rubber, only a small amount of ozone is necessary and the consumption of energy for ozone production is also small. Levels of ozone in the range of about 0.01 to 30%, preferably 0.5 to 10%, still more preferably about 0.1 to 1% by volume are normally utilized, depending upon the number of tires processed, energy availability and the type of operation, batch or continuous processing. Strain levels ranging from about 3 to 30%, preferably 3-10%, are utilized to conserve energy. A mechanical strain of about 0.5 Kg/cm 2 produces a strain level of about 3%-5%.
During experimental testing of this invention, spent automobile tires reinforced with steel cords were placed in a closed chamber. Air containing 0.1-1% of ozone was pumped through the chamber, and the tires were exposed to a shrinking and stretching strain by placing a weight thereon, such that the loading was from 10-200 Kg to achieve a quality of relative deformation from 1-10%. This treatment resulted in the disintegration of the treads and outside part of the tires and separation of the steel wires from the rubber fragments. The time necessary for the achievement of the tire disintegration was 5-10 minutes. It was also found that increasing the ambient ozone concentration and increasing the strain loading within the stated range, decreased the destruction or disintegration time.
In terms of the measurement of ozone consumption made during the initial testing of the invention, the amount of ozone necessary for strained tire destruction is less than 10 gm of ozone per kilogram of tire weight. The energy expense of ozone production is equal to 16 KW hour per kilogram of ozone for air ozonation and 8 KW hour for oxygen ozonation. Energy expenses for the creation of strain which keeps the tires in a deformed state, whether mechanical or static, are a small part of the total energy expense and less than expenses involved in repeated shock strain used in prior known techniques. Thus, by processing of a strained reinforced rubber product in an ozone-rich gas mixture, the aim of the invention is achieved.
By withdrawal and recirculation of the ozone remaining in the reaction chamber or by catalytically destroying any residual ozone in the chamber, there is no adverse environmental impact from ozone use. The process can, thus, be carried out in any location, and need not be located in remote areas resulting in additional transportation costs.
Time of processing decreases with increasing ozone concentration, but increasing the ozone in a gas mixture above 10% is inexpedient because of the significant increase in energy expenses for ozone production. The efficacy of ozone may be increased by the inclusion of appropriate additives which do not negatively contribute to environmental concerns. Decreasing ozone concentration below 0.01% and decreasing load strains below about 0.5 Kg/cm 2 increase processing time considerably. Thus, the preferred range of ozone in the gas mixture is about 0.05 to 10% with a mechanical load or strain of at least 0.5 Kg/cm 2 . When the load on the tire is about 10-200 Kg to produce a deformation of 1-10% of the tire volume, the time period for processing the spent tire is about 5 to 10 minutes.
For the operation of a large plant and the continuous processing of large quantities of rubber products such as reinforced rubber tires, the energy expenditure determines the total costs of the processing operation. In such a case, it is more economical to produce ozone from oxygen with small energy expenditure and locate the plant at or near an oxygen generation facility to minimize transportation costs. Such a continuous processing plant is shown in FIG. 1.
For a portable tire processing station or unit, which can be easily transported to the location of a tire dump site or the like, factors such as transportation or other processing costs may make it more economical and expedient to produce ozone from atmospheric air. The air may be dried, cooled or otherwise treated using known methods if preferred to facilitate the process. The air may also be used without further drying to minimize operation costs if the moisture content is not too high. A portable unit such as the one just described is illustrated in FIG. 2.
Installation and apparatii for carrying out the invention both in the continuous and batch-wise mode are illustrated in FIGS. 1 and 2. FIG. 1 illustrates an apparatus for the continuous processing of steel belted rubber tires and similar products while FIG. 2 illustrates a portable or relocatable apparatus for batch-type or single tire processing.
As show in the FIG. 1 schematic illustration, the apparatus broadly comprises a housing 10 defining therein a treatment or decomposition chamber 11 and input and output sluice-gates 12 and 13. Product 14 is loaded by means of feed conveyor 15 through input sluice-gate 12 into treatment chamber 11. Product fragments 16 remaining after ozone treatment are removed from chamber 11 through output sluice-gate 13. While not shown, sluice gates 12 and 13 are provided with seals to ensure that there is no leakage of the ozone/gas mixture therethrough. The construction and operation of such seals in known in the art.
The fragments 16 which may consist of pieces of rubber and metal wires or fabric threads, are passed through separation chamber 17. Chamber 17 includes a separator 18 which separates metal or fabric from the rubber. Separator 18, schematically illustrated in FIG. 1, may be a sieve or a movable magnet assembly. When the reinforcement material of product 14 is non-metallic such as nylon or fabric, separator 18 may include an extendable arm or belt assembly or an air-flow arrangement designed to collect the nonmetallic components and removing the same from the flow of fragments 16. Conveyor 19 removes pieces of rubber for further treatment such as, for example, a shredder or pulverizer. Conveyor 20 removes metallic wires for compaction or further treatment.
A gas circulation assembly generally indicated at 30 comprises an ozonizer 21, gas preparator 23, compressor 22, valve system 27, a gas source 29 and an ozone destroyer 28. Gas source 29 may be an oxygen producing apparatus, oxygen gas cylinder, air cylinder or an air compressor. Valve system 27 controls the rate of ozone flow into and out of chamber 11 through sluice gates 12 and 13, gas preparator 23, compressor 22 and ozone destroyer 28. Ozone destroyer 28 may be a catalytic or other type of apparatus known in the art for destroying ozone. Other remaining, nontoxic gases may be removed from ozone destroyer 28 by an exhaust system as known in the art.
Ozone (O 3 ) is directed into chamber 11 as an ozone/gas mixture where the ozone content constitutes about 0.01% to 10% by volume of the mixture. Ozonizer 21 is the source for the production of the ozone/gas mixture. The operation of an ozonizer for producing and controlling ozone/gas mixture is known in the art. Thus, the description thereof is deemed unnecessary. Either air or oxygen is pumped into ozonizer 21 by compressor/pump 22. The air may be dried over a suitable drying agent such as CaO, cooled after compression or otherwise suitably treated in gas preparator 23 prior to being pumped into ozonizer 21. Power to ozonizer 21 is supplied by the high voltage power supply 24.
Ozone containing gas mixture (air or oxygen) is directed into chamber 11 by gas distribution assembly 25 which directs it directly to deformation assembly 26 which may comprise rotating rollers as shown in FIG. 1. The rotating speed of rollers in roller assembly 26 may also be varied such that each roller rotates at a different speed, thereby subjecting the rubber tire to a stretching strain in addition to the strain produced by compression between the rollers. The rollers in assembly 26 are driven by a motor not shown in FIG. 1.
Roller assembly 26 is designed to cause a deformation of the product 14 and place a strain on the rubber to a level of at least 0.5 Kg/cm 2 for increasing the rate of product disintegration. As an alternative to assembly 26, a series of weights may be placed on the product 14 to produce the desired strain level.
Housing 10, input and output sluice gates 12 and 13 and roller assembly 26 may be constructed out of stainless steel, glass, wood, ozone-resistant plastic or other materials which are chemically compatible with the ozone/gas mixture used in treatment chamber 11.
FIG. 2 schematically illustrates a portable apparatus made in accordance with the invention for carrying out the disposal operation batch-wise for a single or multiple tire or other products.
FIG. 2 shows a housing 10' defining therein a treatment chamber 11' for disposal of product 14', ozonizer 21' and a ventilator 32'. Housing 10' is provided with sealable top access door 30' through which product 14' may be placed inside treatment chamber 11' and a bottom access door 31' through which rubber and nonrubber fragments remaining after treatment may be removed. The ventilator 32' provides and controls air/gas circulation inside chamber 11' through ozonizer 21' is such a way as to maintain the necessary ozone content in the gas mixture in chamber 11'.
The apparatus of FIG. 2 may be connected to other devices for further processing of the rubber and/or nonrubber fragments as described earlier. The apparatus of FIG. 2 may additionally include the ozone destroyer assembly 28 and the deformation assembly 26 of FIG. 1. It may include a mechanical press in place of the roller assembly.
The portable apparatus of FIG. 2 is simple in construction and requires small amounts of energy for operation.
It has thus been shown that the invention provides a method and apparatus for destruction or disintegration of used or spent reinforced or unreinforced rubber products, such as steel-belted tires or conveyor belts, which is energy efficient, cost-effective, and environmentally non-polluting. By placing a product, such as a tire in an ozone-containing gas mixture with an ozone concentration in the range of from 0.01 to 10% and then exposing the tire to mechanical or static deformation causing a strained condition of the rubber with a strain level of at least 0.5 Kg/cm 2 , the rubber breaks down whereafter the reinforcement material can be recovered or removed therefrom.
While specific embodiments of the apparatus have been illustrated and/or described for carrying out the method of the invention, other apparatus which comprise the basic features required for rubber product disintegration may be utilized. It has thus been shown that the present invention provides an apparatus and a method which overcomes the problems of the prior art methods while enabling scale-up to accommodate high-volume throughput for tire treatment. Thus, the present invention provides a substantial advance in the state of this art.
The foregoing description of the preferred embodiments of the subject invention have been presented for purposes of illustration and description and for a better understanding of the invention. It is not intended to be exhaustive or to limit the invention to the precise form disclosed; and, obviously, many modifications and variations are possible in the light of the above teaching. The particular embodiments were chosen and described in some detail to best explain the principles of the invention and its practical application thereby to enable others skilled in the relevant art to best utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. It is intended that the invention be defined by the claims appended hereto. | An apparatus and method for energy efficient recycling of reinforced rubber products, such as tires, conveyor belts, and the like, wherein the rubber is reinforced by cords or belts of steel, nylon, fabric and the like. The presence of the reinforcement materials poses not only a necessity to separate the rubber therefrom but also poses a problem of disposing of the reinforcement materials. By placing the reinforced rubber in an environment of ozone (O 3 ) and applying a force to the rubber, the rubber breaks down leaving the reinforcement materials for ready disposal. The method and apparatus thereby provide an energy efficient, cost-effective, and environmentally safe and acceptable technique for recycling reinforced rubber products. | 1 |
FIELD OF THE INVENTION
[0001] The present invention relates to disinfecting articles providing effective cleaning and antimicrobial treatment of microbiologically contaminated surfaces. More particularly, it relates to the use of aqueous hypohalite compositions associated with a hypohalite stable and hypohalite non-degrading absorbent substrate that preserves the antimicrobial efficacy of the disinfectant article over representative storage times and/or storage conditions. The wipe substrate is selected from hypohalite stable materials that do not catalyze decomposition of the associated aqueous hypohalite compositions.
BACKGROUND OF THE INVENTION
[0002] There is a need for a stable cleaning and disinfecting wipe and article that is capable of cleaning and removing residues from soiled surfaces while simultaneously destroying undesirable microorganisms, e.g. bacteria, mold, viruses, prions and the like that colonize on common surfaces with which people come into contact, such as doorknobs, countertops, toilet seats, floors, beds, walls, and the like.
[0003] Hypohalite releasing compounds, such as the hypohalites and related compounds that release active forms of hypohalite and/or halogens, are extremely effective disinfectants capable of destroying a wide range of microorganisms. Hypohalite releasing antimicrobial compounds, and in particular the hypohalites, constitute a class of strong chemical oxidants possessing both cleaning and bleaching properties in addition to their antimicrobial properties making them superior to other disinfectants, such as quaternary ammonium biocides. The hypohalite class of chemical oxidants act to rapidly oxidize susceptible substances found in inorganic, organic and biological materials, rendering them more easily removed from surfaces, and in the case of colored or pigmented materials, bleaching them to white or colorless end products resulting in effective cleaning and stain removal from soiled surfaces. Owing to their strong oxidizing capability, hypohalites also posses inherent disinfection properties and additionally possess desirable characteristics including excellent aqueous solubility, mobility and a highly dissociative ionic nature. A further advantage of the hypohalite class with regard to disinfectancy, is the speed and efficacy with which they attack microorganisms and either destroy them or render them non-viable following very short contact times. Yet a further advantage of the hypohalites is the wide susceptibility of many different types of microbial pests to their strong oxidizing potential and essentially the absence of any known microbe to develop an effective resistance against the action of these materials.
[0004] Typically, microbiologically contaminated surfaces seldom comprise only the microorganisms themselves, but include the presence of soils and other residues, including organic, inorganic and biological residues associated with the source of the microbiological contamination. These residues, including, for example, saliva, bodily fluids, blood and common soils such as foods, oils and dirt, not only host microorganisms, but can act to shield and protect the microorganisms from the disinfectant action of non-hypohalite disinfectant materials.
[0005] One seeming disadvantage of the hypohalite class of materials is their susceptibility to decomposition, including self-decomposition and reactive decomposition owing to the interaction of the hypohalites with the substrates and materials in which they come into contact during storage, such as packaging materials, and particularly in the case of pre-wetted wipes, the material used as the absorbent carrier substrate which is impregnated with the disinfectant composition. Hence, freshly prepared solutions or disinfectant articles utilizing these materials are typically required to ensure adequate activity for ensuring effective disinfection of surfaces. Attempts have been made in the past to provide a convenient disinfectant article by absorbing a hypohalite solution onto an absorbent towel or carrier. However, prior attempts have failed to produce a hypohalite releasing disinfectant wipe with sufficient stability to ensure suitable disinfecting efficacy at time of use, particularly following typical storage times and/or less than ideal storage conditions representative of real world environments encountered in the home, office, business, hospital or field where needed.
[0006] U.S. Pat. No. 4,998,984, to McClendon, describes a premoistened disinfectant article impregnated with a disinfectant composition that may include sodium hypochlorite and is prepackaged in a liquid impermeable container. U.S. Pat. No. 5,087,450, to Lister, describes a viral wipe to remove organic material having viral contaminants from a surface which consists of a porous gauze pad lined with a non-porous flexible fluid impervious barrier layer fused to one side and impregnated with 10% sodium hypochlorite and stored in a protective foil, plastic and paper layered package. Lister notes that the 10% sodium hypochlorite solution becomes unstable within a short period of time.
[0007] U.S. Pat. No. 5,985,302, to Dorr, et al., describes a method for inactivating HIV infected blood which involves first swabbing a contaminated surface with a first aqueous calcium and/or sodium hypochlorite impregnated fibrous towlette, followed by a second swabbing with a second towlette impregnated with a neutralizing sodium thiosulfate solution. However, the Dorr et al. example exhibits poor stability and complete loss of inactivating activity even of a dry calcium hypochlorite/methyl cellulose system freshly dissolved in water to produce a disinfecting solution after only 10 days storage at 50° C. U.S. Pat. No. 6,313,049, to Heady and Wolkensperg, describes a pre-packaged fabric-saturated absorbent sheet with the U.S. food-industry legal chlorine disinfectant solution and discloses the use of cotton, paper or sponge sheets as absorbents. U.S. Pat. No. 6,387,384, to Probert and Probert, describes a prepackaged towlette bearing sodium hypochlorite and discloses the use of gauze or bandage material as absorbents.
[0008] The prior art fails to provide a stable disinfectant article that maintains acceptable stability after representative storage times and storage conditions typical of actual usage conditions encountered in the real world. For instance, most commercial product distribution channels result in products ageing several months following manufacture before being placed on sale, followed by signifcant delays before actually being used. During this time, products are seldom stored under ideal conditions, but rather are exposed to temperature variations typical of the home, field and industrial environment. Most significantly, the prior art fails to disclose suitable absorbent carrier substrates with acceptable stability nor a reliable means for selecting an appropriate absorbent material suitable for extended stability of aqueous hypohalite disinfectant articles to ensure reliable antimicrobial efficacy when needed.
[0009] Clearly, there remains an unmet need for an aqueous hypohalite disinfecting article with improved stability that can provide the required antimicrobial efficacy for disinfecting microbiologically contaminated surfaces, particularly following typical storage times and/or less than ideal storage conditions representative of real world environments encountered in the home, office, business, hospital or field where needed.
SUMMARY OF THE INVENTION
[0010] 1. In accordance with the above objects and those that will be mentioned and will become apparent below, one embodiment of the invention comprises a disinfecting article comprising:
a. an aqueous hypohalite releasing composition, b. an absorbent carrier, and c. a packaging system dispensibly housing a single or multiple number of disinfectant substrates, wherein said disinfectant article maintains the stability of the hypohalite releasing composition of at least 25% after 11 days at 120° F.
[0014] 2. An additional embodiment of the invention comprises a method of disinfecting hard surfaces comprising treating the hard surface with a disinfecting article comprising:
a. an aqueous hypohalite releasing composition, b. an absorbent carrier, and c. a packaging system dispensibly housing a single or multiple number of disinfectant substrates, wherein said disinfectant article maintains the stability of the hypohalite releasing composition of at least 25% after 11 days at 120° F.
[0018] 3. An additional embodiment of the invention comprises a hypochlorite-containing disinfecting wipe with improved stability that provides superior germ killing on surfaces such as countertops, floors, beds, walls, doorknobs, toilet seats, and the like.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] Further features and advantages will become apparent from the following and more particular description of the preferred embodiments of the invention, as illustrated in the accompanying FIG. 1 .
[0020] FIG. 1 Graph of remaining available chlorine on absorbent substrates under accelerated storage test conditions.
INVENTIVE EXAMPLE 1
[0021] Disinfectant wipe with Composition 1 (Table 1) loaded onto a 100% polyester substrate, stored in an upright sealed canister for up to 6 weeks at a temperature of 120° F.
INVENTIVE EXAMPLE 2
[0022] Disinfectant with Composition 2 (Table 1) loaded onto an identical 100% polyester substrate and stored as in Example 1 herein.
COMPARATIVE EXAMPLE J
[0023] Disinfectant wipe with Composition 1 (Table 1) loaded onto 100% polypropylene substrate following Example J (Table 2), and stored as in Example 1 herein.
Commercial Wipe
[0024] Dispatch Hypochlorite Wipes, stored as supplied in individually sealed packages, for up to 3 weeks at a temperature of 120° F.
DETAILED DESCRIPTION OF THE INVENTION
[0025] Before describing the present invention in detail, it is to be understood that this invention is not limited to particularly exemplified systems or process parameters as such may, of course, vary. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments of the invention only, and is not intended to limit the scope of the invention in any manner.
[0026] All publications, patents and patent applications cited herein, whether supra or infra, are hereby incorporated by reference in their entirety to the same extent as if each individual publication, patent or patent application was specifically and individually indicated to be incorporated by reference.
[0027] It must be noted that, as used in this specification and the appended claims, the singular forms “a,” “an” and “the” include plural referents unless the content clearly dictates otherwise. Thus, for example, reference to a “surfactant” includes two or more such surfactants.
[0028] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the invention pertains. Although a number of methods and materials similar or equivalent to those described herein can be used in the practice of the present invention, the preferred materials and methods are described herein.
[0029] The following examples illustrate disinfecting articles and compositions of the described invention. The exemplified compositions are illustrative only and do not limit the scope of the invention. Unless otherwise specified, the proportions in the examples and elsewhere in the specification are by weight percent of the total liquid composition, and loading levels of the example compositions are by unit weight of composition per unit weight of the absorbent carrier matrix and thus expressed as a unit-less weight/weight ratio.
[0030] The present invention relates to a disinfecting article and wipe for cleaning and disinfecting surfaces, in which the disinfecting article comprises an aqueous hypohalite releasing composition adsorbed onto a hypohalite stable and hypohalite non-degrading absorbent carrier material. The disinfecting articles comprise:
(a) an aqueous hypohalite releasing composition, and; (b) an absorbent carrier comprising a substrate that is hypohalite stable and hypohalite non-degrading, that is a substrate that does not catalyze the decomposition of the hypohalite releasing composition, and; (c) a packaging system dispensibly housing a single or multiple number of disinfectant substrates.
[0034] The present invention is directed to hypohalite stable and hypohalite non-degrading absorbent carrier materials for holding and dispensing aqueous antimicrobial hypohalite releasing compositions. The present invention is also directed to stable aqueous hypohalite compositions that are preferably used in association with hypohalite stable and hypohalite non-degrading absorbent carrier materials. The present invention is further directed to a disinfectant article and packaging system such as an upright canister for storing and conveniently dispensing a continuous number of individually dividable wipes on demand, while providing for extended stability and disinfectant efficacy owing to improved stability of the associated hypohalite releasing disinfectant compositions absorbed onto the absorbent carrier materials.
[heading-0035] Absorbent Carrier
[0036] Suitable absorbent carriers may be provided by a variety of sources, including woven and non-woven webs, fabrics, foams, sponges and similar material constructs capable of absorbing the liquid disinfectant composition of the present invention. Generally, the absorbent carrier is preferred to be in sheet form, that is, in a form in which the cross-sectional thickness dimension of the absorbent carrier is proportionally smaller than either its approximate width or length dimension in order to provide at least one surface whose surface area is sized appropriately with respect to the intended surface to be treated with the disinfectant article. The absorbent carrier may be formed into individual sheets or wipes, or a continuous sheet, preferably with some separation means provided, such as partial tears or perforations across at least one dimension of the sheet, such that the sheet may be subdivided prior to use to a suitable size for the particular need at hand.
[0037] The absorbent carrier may consist of a single layer, or multiple layers of one or more materials, or combination of one or more materials and/or one or more forms of materials, wherein multiple layers or multiple forms are bound by a suitable means to each other to prevent separation. For example, a sheet of one material may be combined with a second sheet of a second material, and bound together by a suitable means, such as by adhesion, heat or sonic welding, to prevent their separation. As a further example, a non-woven sheet of one material may be combined with a second material formed into deformable and compressible foam, and bound together by a suitable means. In this manner, all conceivable combinations of materials may be combined to provide useful articles for a variety of cleaning and disinfecting requirements.
[0038] Further, the absorbent carrier can be combined with non-absorbent materials, preferably in the form of films, sheets or blocks. Preferably, the non-absorbent materials are liquid impervious, in that they do not permit the passage of the disinfectant compositions of the present invention. In one example, the non-absorbent materials may be bonded to one side of a suitable absorbent carrier in order to provide a liquid impervious barrier to prevent passage of the disinfectant compositions from the absorbent material to the non-bonded surface of the barrier material. One example would be an absorbent material in a thin sheet form bonded with a liquid impervious barrier film in thin sheet form to one side of the absorbent material forming an effective barrier to the disinfectant compositions that would allow the layered disinfectant article to be handled by the user without direct contact with the disinfectant wetted side of the layered article. Another example would be a thin liquid impervious plastic sheet bounded to an absorbent foam, whereby the user would only come into contact with the plastic sheet during use rather than the liquid disinfectant absorbed into the foam that is displaced by pressure applied while wiping the surface to be treated.
[0039] According to the present invention, the absorbent carrier may be produced by any method known in the art. For example non-woven material substrates can be formed by dry forming techniques such as air-laying or wet laying such as on a paper-making machine. Other non-woven manufacturing techniques such as hydroentangling, melt blown, spun bonded, needle punched and related methods may also be used. However, the substrate must be made substantially free of binder or latex and other impurities that may degrade or interact with the disinfectant composition. Many manufacturing techniques, such as air-laying, do not lend themselves to the formation of binder- and latex-free absorbent carriers. As such they are not preferred manufacturing techniques. Hydroentrangling manufacturing techniques using high speed water jets are generally preferred due to the high density matrices produced and owing to the high water flow volume the high degree of cleanliness of the resulting non-woven articles produced by this method.
[0040] Suitable absorbent carriers are generally selected from man-made and synthetic construction materials or substrates. Suitable construction materials include synthetic polymers. For good cleaning, absorption, handling and loading characteristics, it is desirable that the absorbent carrier materials be in the form of fiber, webs or foams of the suitable construction materials. Suitable forms employing fibers include woven and non-woven structures. Woven structures include meshes, screens, knits, fabrics and other similarly woven structures that are of sufficiently high fiber count and strength to be handled by typical machinery and process equipment needed for forming, cutting and packaging the disinfectant articles, preferably when in a dry state. Suitable structures include those structures that are of sufficiently high fiber count and strength to be dispensed and handled during use, preferably when in a dry state, and more preferably when in a wetted state. Suitable woven and non-woven structures are composed of fibers with both sufficiently fine fiber sizes and fiber densities to provide some absorption capacity and enable loading of a sufficient quantity of the disinfectant solution so as to provide for effective treatment of surfaces. Suitable non-woven structures include those structures that are of sufficiently high fiber count and strength to be dispensed from the packaging articles without significant deformation, tearing or ripping and handled during use without unraveling, abrading or tearing, preferably when in a wetted state.
[heading-0041] Absorbent Carrier Substrates
[0042] Suitable substrates employed for constructing the absorbent carrier may be provided by a variety of sources, and include all suitable substrate that are hypohalite stable, in that they undergo no significant degradation, that is no significant chemical or physical change in structure, properties or form, owing to contact with the disinfectant compositions employed in the present invention, even after extending contact or storage times under representative storage conditions. Preferred are suitable substrates that do not cause significant degradation of the associated or absorbed disinfecting compositions, that is, substrates that do not catalyze or significantly accelerate the decomposition of the associated hypohalite compositions.
[0043] Suitable materials of construction generally include synthetic polymer substrates, such as polyethylene terephthalate (PET), polyester (PE), high density polyethylene (HDPE), polyvinyl chloride (PVC), chlorinated polyvinylidene chloride (CPVC), polyacrylamide (ACAM), polystyrene (PS), polypropylene (PP), polycarbonate (PC), polyaryletherketone (PAEK), poly(cyclohexylene dimethylene cyclohexanedicarboxylate) (PCCE), poly(cyclohexylene dimethylene terephthalate) (PCTA), poly(cyclohexylene dimethylene terephtalate) glycol (PCTG), polyetherimide (PEI), polyethersulfone (PES), poly(ethylene terephthalate) glycol (PETG), polyketone (PK), poly(oxymethylene); polyformaldehyde (POMF), poly(phenylene ether) (PPE), poly(phenylene sulfide) (PPS), poly(phenylene sulfone) (PPSU), syndiotactic polystyrene (syn-PS), polysulfone (PSU), polytetrafluoroethylene (PTFE), polyurethane (PUR), poly(vinylidene fluoride) (PVDF), polyamide thermoplastic elastomer (TPA), polybutylene (PB), polybutylene terephthalate (PBT), polypropylene terephthalate (PPT), polyethylene naphthalate (PEN), polyhydroxyalkanoate (PHA), poly(methyl)methacrylate (PMMA) and polytrimethylene terephthalate (PTT).
[0044] Suitable materials of construction also include copolymers made from the following monomers: acrylonitrile-butadiene-styrene (ABS), acrylonitrile-styrene-acrylate (ASA), ethylene-propylene (E/P), ethylene-vinyl acetate (EVAC), methyl methacrylate-acrylonitrile-butadiene-styrene (MABS), methacrylate-butadiene-styrene (MBS), melamine-formaldehyde (MF), melamine-phenol-formaldehyde (MPF), phenol-formaldehyde (PF), styrene-butadiene (SB), styrene-maleic anhydride (SMAH), copolyester thermoplastic elastomer (TPC), olefinic thermoplastic elastomer (TPO), styrenic thermoplastic elastomer (TPS), urethane thermoplastic elastomer (TPU), thermoplastic rubber vulcanisate (TPV), copolymer resins of styrene and acrylonitrile (SAN), styrene butadiene copolymer (SBC) and vinyl acetate-ethylene copolymer (VAE). Preferably, the substrate is selected from the group consisting of polyester, modified polyester, and polyester blends.
[0045] The substrate and the absorbent carrier constructed from said substrate herein is substantially free, preferably devoid, of any binders or latex materials. Substantial elimination of binders and latexes, and the like, can be accomplished by pre-washing the dry absorbent carrier in soft, distilled or de-ionized water or other solvents, or by using a process, such as hydroentangling (also known in the art as spunlace technology). More specifically, in the hydroentangling process, a fibrous web is subjected to high-velocity water jets, preferably employing de-ionized, distilled or soft water that entangle the fibers. The non-woven material may then be subjected to conventional drying and wind-up operations, as known to those skilled in the art. Since the hydroentangling process precludes the use of binders, and can be used to wash off fiber latexes, it is the most preferred process to be used in the manufacture of materials of construction of the present invention.
[0046] Suitable materials of construction that are readily available in commerce include the SONTARA® brand of non-woven fabrics produced by Dupont. Representative materials include 100% polyester substrate materials designated SONTARA® 8001, 8005H, 8010 and 8061, and 50% polyester/50% Dacron® blends designated SONTARA® 8100 and including hydrophilically modified 100% polyester substate material designated SONTARA® 8005H. Additional examples include materials commercially available from Polymer Group Inc, including 100% spunlaced polyester materials designated M001, M022, M040X, CG003, CG005, CG2009, M017 and N2006. Representative materials also include spunlaced 100% polyester materials available from Jacob Holms Industries, designated as 350160 and 10203-003.
[heading-0047] Absorbency and Loading
[0048] The absorbent carrier preferably has a weight of from about 10 gm −2 (grams per meter squared) to about 200 gm −2 . More preferably, the absorbent carrier has a weight of at least about 15 gm −2 and more preferably less than about 150 gm −2 , more preferably the basis weight is in the range of about 20 gm −2 to about 120 gm −2 , and most preferably from about 25 gm −2 to about 100 gm −2 .
[0049] In preparing pre-wetted disinfectant articles according to the present invention, the composition is applied to at least one surface of the absorbent carrier material. The composition can be applied at any time during the manufacture of the articles. Preferably the composition can be applied to the absorbent carrier after the absorbent carrier has been dried. Any variety of application methods that evenly distribute disinfecting compositions can be used. Suitable methods include spraying, dipping, or rolling whereby the composition is forced through tubes in contact with the absorbent carrier whilst the absorbent carrier passes across the tube or combinations of these application techniques. For example, spraying the composition on a rotating surface such as calender roll that then transfers the composition to the surface of the absorbent carrier. The composition can be applied either to one surface of the absorbent carrier or both surfaces, and preferably both surfaces.
[0050] The composition can also be applied uniformly or non-uniformly to the surfaces of the absorbent carrier. By non-uniform it is meant that for example, the amount or pattern of distribution of the composition can vary over the surface of the absorbent carrier. For example, some of the surface of the absorbent carrier can have greater or lesser amounts of disinfectant composition, including portions of the surface that do not have any composition on it. Preferably however the composition is uniformly applied to the surfaces of the absorbent carrier, or most preferably to the absorbent surface of the disinfectant article that comprises multiple layers or multiple materials of construction.
[0051] Preferably, the composition can be applied to the absorbent carrier at any point after it has been dried. For example, the composition can be applied to the absorbent carrier prior to calendaring or after calendaring and prior to being wound up onto a parent roll. Typically, the application will be carried out on an absorbent carrier unwound from a roll having a width equal to a substantial number of wipes it is intended to produce.
[0052] When the absorbent carrier matrix is produced with a bonded liquid impervious layer forming an essentially impervious barrier to one side of the disinfectant article, it is then preferred that application of the disinfectant composition is made to the absorbent side of the article.
[0053] Alternatively, the disinfectant composition can also be applied at a later stage in the processing of the disinfectant articles, being applied to the substantially dry absorbent carrier after it has been placed into the respective storage pouch, container, canister or other packaging means, but prior to sealing or closure of said packaging means. In this alternative application means, the disinfectant solution is preferably applied by spraying, dripping or nozzle injection of a metered aliquot of the liquid disinfectant composition directly onto the absorbent material within each open package at a convenient processing stage.
[0054] The composition is typically applied in an amount of from about 1 gram to about 10 gram per gram of absorbent carrier, preferably from about 1.5 gram to about 8.5 gram per gram of absorbent carrier, most preferably from about 2 gram to about 5 gram per gram of dry absorbent carrier.
[0055] Those skilled in the art will recognize that the exact amount of aqueous composition applied to the absorbent carrier will depend on the basis weight of the absorbent carrier and on the end use of the product. In one preferred embodiment, a relatively low basis weight absorbent carrier, from about 20 gm −2 to about 80 gm −2 is used in the making of a pre-moistened cleaning and disinfectant wipe suitable for cleaning lightly soiled counters, stove tops, cabinetry, walls, sinks and the like. For such end uses, the dry absorbent carrier is loaded with an aqueous composition of the invention at a factor of from about 2 grams to about 10 grams per gram of dry absorbent carrier. In another preferred embodiment, a higher basis weight absorbent carrier, from about 40 gm −2 to about 200 gm −2 is used in the making of the pre-moistened disinfectant wipe suitable for cleaning heavily soiled or larger area surfaces, including floors, walls and the like. In such instances, the wipe may further be sold with, or designed to work with, a hand held implement comprising a handle and designed for wiping and cleaning. Examples of such implements are commercially available under the trade names Ready-Mop®), a product of The Clorox Company, and Swiffer®), a product of the Procter and Gamble Company. For such end uses, the dry absorbent carrier is loaded with an aqueous composition of the invention at a factor of from about 2 grams to about 8 grams per gram of dry absorbent carrier.
[heading-0056] Disinfectant Compositions
[heading-0057] Disinfectant Actives
[0058] Suitable hypohalite bleaches may be provided by a variety of sources, including bleaches that lead to the formation of positive halide ions and/or hypohalite ions, as well as bleaches that are organic based sources of halides, such as chloroisocyanurates, haloamines, haloimines, haloimides and haloamides, or mixtures thereof. These bleaches also produce hypohalite-bleaching species in situ. Suitable hypohalite bleaches for use herein include the alkali metal and alkaline earth metal hypochlorites, hypobromites, hypoiodites, chlorinated trisodium phosphate dodecahydrates, potassium and sodium dichloroisocyanurates, potassium and sodium trichlorocyanurates, N-chloroimides, N-chloroamides, N-chlorosulfamide, N-chloroamines, chlorohydantoins such as dichlorodimethyl hydantoin and chlorobromo dimethylhydantoin, or mixtures thereof.
[0059] In a preferred embodiment wherein the compositions herein are liquid, said hypohalite bleach is an alkali metal and/or alkaline earth metal hypochlorite, or mixtures thereof. More preferably, for liquid compositions said hypohalite bleach is an alkali metal and/or alkaline earth metal hypochlorite selected from the group consisting of sodium hypochlorite, potassium hypochlorite, magnesium hypochlorite, lithium hypochlorite and calcium hypochlorite, and mixtures thereof. Even more preferably, for liquid compositions said hypohalite bleach is sodium hypochlorite.
[0060] The halogen bleach is present in an amount from above zero to about 15 weight percent of the composition and preferably from about 0.001 weight percent (10 ppm) to about 10 weight percent of the composition, and most preferably from about 0.005 (50 ppm) to about 5 weight percent of the composition. A particularly preferred bleach in this invention is sodium hypochlorite, having the chemical formula NaOCl, present in an amount ranging from about 0.001 to about 15 weight percent of the composition, more preferably from about 0.005 (50 ppm) to about 10 weight percent, and most preferably from about 0.005 (50 ppm) to about 5 weight percent of the composition.
[heading-0061] Electrolyte/Buffer
[0062] The electrolyte/buffer component of the cleaning and disinfecting composition appears to promote a favorable environment of pH and ionic strength in which the hypohalite releasing disinfectant is stabilized against accelerated decomposition and loss of disinfectant efficacy. An electrolyte functions to provide a source of ions (generally anions) in aqueous solution. The electrolyte thus provides a charged medium in which the optional surfactant and/or optional thickeners can associate to provide thickening, or other favorable rheological properties such as shear thinning and/or viscoelastic properties, which provide for thickened compositions that may be readily formulated, mixed and handled by commercial processing equipment and effectively transferred by commercial pumping and dosing equipment for convenient loading onto the absorbent carrier. Suitably thickened and rheologically enhanced disinfecting compositions provide the additional benefit of higher loading capabilities onto their respective absorbent carriers, reduced dripping and evaporation during storage and use. Suitably thickened and rheologically enhanced disinfecting compositions also provide the additional benefit of clinging to treated surfaces, particularly uneven, sloped or vertical surfaces with greater tenacity and resistance from gravity to provide more efficient coverage, effective contact time and overall enhancing the cleaning and disinfectant efficacy of the compositions.
[0063] A buffer principally acts to maintain a favorable pH of the associated aqueous disinfectant compositions, particularly when absorbed in intimate contact with the absorbent carrier materials employed. In the present invention, alkaline pH is favored for purposes of maintaining halogen bleach stability. Some compounds will serve as both electrolyte and buffer. These particular electrolyte/buffer compounds are generally various inorganic acids, for example, borates, polyphosphates, pyrophosphates, triphosphates, tetraphosphates, silicates, metasilicates, polysilicates, carbonates, and hydroxides; alkali metal salts of such inorganic acids; and mixtures of same. Certain divalent salts, e.g., alkaline earth salts of phosphates, carbonates, hydroxides, etc., can function singly as buffers. If such a divalent salt compound were used, it would be combined with at least one of the above-mentioned electrolyte/buffer compounds to provide the appropriate pH adjustment. It may also be suitable to use materials such as aluminosilicates (zeolites), borates, aluminates and bleach-stable organic materials, such as the lower C1-C10 alkyl dicarboxylic acids including gluconates, succinates, and maleates, as buffers. Sodium chloride or sodium sulfate can be used as electrolytes, but not buffers, if necessary, to maintain the ionic strength necessary for the desired rheology, if optional surfactants and/or thickeners are employed.
[0064] An especially preferred electrolyte/buffer compound is an alkali metal silicate, which is employed in combination with an alkali metal hydroxide to provide effective pH control and can also function as a metal ion sequestrant. The preferred silicate is sodium silicate, which has the empirical formula NaO:SiO. 2 . The ratio of sodium oxide: silicon dioxide is about 1:4 to 1:1, more preferably about 1:2. Silicates are available from numerous sources, such as the PQ Corporation. The electrolyte/buffer compounds function to keep the pH range of the inventive cleaning and disinfecting composition preferably above 7.0, more preferably at between about 10.0 to about 14.0, and most preferably at between about 11.5 and 13.5. The amount of electrolyte/buffer can vary from about 0.01 to about 10 weight percent of the composition, more preferably from about 0.05 to about 5 weight percent of the composition, and most preferably from about 0.05 to about 1.0 weight percent of the composition.
[heading-0065] Water
[0066] It should be noted that the main ingredient in the inventive compositions is water, preferably softened, distilled or deionized water. Water provides the continuous liquid phase into which the other ingredients are added to be dissolved/dispersed. The amount of water present generally exceeds 90% and, indeed, can be as high as 99.9%, although generally, it is present in a quantity sufficient (q.s.) to take up the remainder of the specially formulated disinfectant compositions of the present invention.
[heading-0067] Surfactant
[0068] Optionally, a surfactant suitable for use in this invention is selected from anionic, non-ionic, amphoteric, zwitterionic surfactants and mixtures thereof. It is especially preferred to use a combination of anionic and bleach-stable, non-ionic surfactants. The anionic surfactant is selected from bleach-stable surfactants such as alkali metal alkyl sulfates, secondary alkane sulfonates (also referred to as paraffin sulfonates), alkyl diphenyl ether disulfonates, fatty acid soaps, and mixtures thereof. Such an anionic surfactant will preferably have alkyl groups averaging about 8 to about 20 carbon atoms. In practice, any other anionic surfactant that does not degrade chemically when in contact with a hypohalite, e.g., hypochlorite, bleaching species should also work.
[0069] An example of a particularly preferred secondary alkane sulfonate is HOSTAPUR SAS, manufactured by Farbwerke Hoechst A. G., Frankfurt, West Germany. Examples of typical alkali metal salts of alkyl benzene sulfonic acids are those manufactured by Pilot Chemical Company sold under the trademark CALSOFT. An example of a typical alkali metal alkyl sulfate is CONCO SULFATE WR, sold by Continental Chemical Company, which has an alkyl group of about 16 carbon atoms. When the electrolyte used is an alkali metal silicate, it is most preferable to include a soluble alkali metal soap of a fatty acid, such as a hexyl to tetradecyl fatty acid soaps. Especially preferred are sodium and potassium soaps of lauric and myristic acid. When used as a component of the inventive cleaning composition, the alkali metal soap of a fatty acid is present in an amount from above zero to about 10 weight percent of the composition.
[0070] Examples of preferred bleach-stable, non-ionic surfactants are amine oxides, especially trialkyl amine oxides, as represented in the formula expression RR′R″NO, in which R′ and R″ may be alkyls of 1 to 3 carbon atoms and are most preferably methyls, and R is an alkyl of about 10 to 20 carbon atoms. When R′ and R″ are both methyl and R is alkyl averaging about 12 carbon atoms, the structure for dimethyldodecylamine oxide, a particularly preferred amine oxide, is obtained. Representative examples of these particular types of bleach-stable, non-ionic surfactants include the dimethyldodecylamine oxides sold under the trademark AMMONYX LO by Stepan Chemical. Yet other preferred amine oxides are those sold under the trademark BARLOX by Lonza, CONCO XA sold by Continental Chemical Company, AROMAX sold by Akzo, and SCHERCAMOX, sold by Scher Brothers, Inc. These amine oxides preferably have main alkyl chain groups averaging about 10 to about 20 carbon atoms.
[0071] Other types of suitable surfactants include amphoteric surfactants such as, for example, betaines, imidazolines and certain quaternary phosphonium and tertiary sulfonium compounds.
[0072] It is suitable to use one or more surfactants in the inventive compositions. In the inventive composition, total surfactant, when present, is included in an amount ranging from about 0.001 to about 20 weight percent of the composition, preferably in an amount ranging from about 0.01 to about 5 weight percent of the composition. For reduced surface residue and to decrease the tendency of the compositions to contribute to excess foaming, residual filming or streaking, and particularly for use on glossy or shiny surfaces, total surfactant present is most preferably from about 0.01 to about 1.0 weight percent of the composition, when included.
[heading-0073] Secondary Surfactant and Hydrotropes
[0074] Optionally, an additional co-surfactant may be added to the disinfectant composition of this invention. Preferred materials include the bleach stable anionic surfactants and hydrotropes. The bleach stable anionic surfactants include alkali metal alkyl sulfates, alkylarylsulfonates, primary and secondary alkane sulfonates (also referred to as paraffin sulfonates), alkyl diphenyloxide disulfonates, and mixtures thereof. The anionic surfactants will have alkyl groups preferably averaging about 8 to 20 carbon atoms. The alkyl arylsulfonic acid salts of preference are linear alkylbenzene sulfonates, known as LAS's. Typical LAS's have C8-16 alkyl groups, examples of which include Stepan Company's Biosoft, and Pilot Chemical Company's Calsoft. Still further suitable surfactants are the alkyldiphenylether disulfonates (also called alkyldiphenyloxide disulfonates), such as those sold by Dow Chemical Company under the name “Dowfax,” e.g., Dowfax 3B2. Still other potentially suitable anionic surfactants include alkali metal alkyl sulfates such as Conco Sulfate WR, sold by Continental Chemical Company, which has an alkyl group of about 16 carbon atoms; and secondary alkane sulfonates such as Hostapur SAS, manufactured by Farbwerke Hoechst AG. Hydrotropes, on the other hand, are dispersants which do not form a critical micelle concentration (CMC) in water (See Colbom et al, U.S. Pat. No. 4,863,633, column 8, line 20 through column 10, line 22, incorporated herein by reference). These hydrotropes may interact with some of the bleach stable surfactants bearing at least one nitrogen atom to form thickened, viscoelastic formulations, although it is again emphasized that the thickening phenomenon is not critical to the enhanced brightness retention of the invention. The hydrotropes are preferably selected from short chain alkylarylsulfonates, salts of benzoic acid, benzoic acid derivatives (such as chlorobenzoic acid), and mixtures thereof. As used herein, aryl includes benzene, naphthalene, xylene, cumene and similar aromatic nuclei. These aryl groups can be substituted with one or more substituents known to those skilled in the art, e.g., halo (chloro, bromo, iodo, fluoro), nitro, or C 1-4 alkyl or alkoxy. Most preferred is sodium xylene sulfonate (such as Stepanate SXS, available from Stepan Company). The bleach stable anionic surfactant and/or hydrotrope should be present in a ratio with the bleach stable surfactant with at least one nitrogen atom (described above in 2.) between about 10:1 to about 1:10. Suitable levels of a secondary surfactant and/or hydrotrope, when employed, are similar to the levels employed for a first surfactant, as referenced herein.
[heading-0075] Sequestrant/Chelant
[0076] Optionally, sequestering agents may be suitable for use in the inventive disinfectant articles. Sequestering agents are selected from the group consisting of metal chelators, metal sequestrants and ion exchange materials known in the art. Preferably, metal chelators and metal sequestrants are selected from the group consisting of the alkali and alkaline earth salts of the phosphates, phosphonates, borates, silicates, polyfunctionally-substituted aromatic chelating agents, ethylenediamine tetra-acetate (EDTA) and ethylenediamine —N,N′-disuccinic acids, or mixtures thereof. Preferred sequestering agents are the silicates and ethylenediamine tetra-acetate.
[0077] Polyfunctionally-substituted aromatic chelating agents may also be useful in the bleaching compositions herein. See U.S. Pat. No. 3,812,044, issued May 21, 1974, to Connor et al. Preferred compounds of this type in acid form are dihydroxydisulfobenzenes such as 1,2-dihydroxy-3,-5-disulfobenzene. A preferred biodegradable chelating agent for use herein is ethylene diamine N,N′-disuccinic acid, or alkali metal, or alkaline earth, ammonium or substituted ammonium salts thereof or mixtures thereof.
[0078] Sequestering agents are also selected from the group consisting of polyacrylic acid, a polyacrylic acid derivative, or a copolymer of acrylic acid or methacrylic acid and a comonomer, which is maleic acid or maleic anhydride. By “polyacrylic acid derivative” is meant copolymers derived from acrylic monomers and non-acrylic monomers. Acrylic monomers generally refer to esters of acrylic acid and methacrylic acid as well as those of other α-substituted acrylic acids (e.g., α-chloroacrylic, and α-ethylacrylic acids). Preferred acrylic monomers include, for example, acrylic acid and methacrylic acid. Suitable non-acrylic acid monomers include, for example, ethylene and propylene.
[0079] Other suitable polycarboxylate sequestering agents include, for example, polymethacrylate (DAXAD 30,35,37™ from W. R. Grace & Co. and ALCOSPERSE 124™ from ALCO Chemical), acrylic acid/methacrylic acid (SOKOLAN CP 135™ from BASF Corp.), an oxidized ethylene/acrylic acid, carboxylated vinyl acetate (DARATAK 78L™ from W. R. Grace), vinyl acetate/crotonic acid (LUVISET CA66™ from BASF Corp.), vinyl acetate/vinyl propionate/crontonic (LUVISET CAP™ by BASF Corp.), vinyl acetate/vinyl neodecanoate/crontonic acid (Resyn 28-2930(by National Starch Co.), vinyl acetate/methacryloxy 1-benzophenone/crontonic acid (RESYN 28-3307™ from National Starch Co.), acrylic acid/methylethyl acrylate, ethylene/maleic acid (EMA™ from Monsanto Co.), poly(isobutylene/maleic acid) (DAXAD 31 ™ from W. R. Grace & Co.), maleic acid/vinyl acetate (LYTRON X 886™ from Monsanto Co.), poly(methyl vinyl ether/maleic acid) (SOKALAN CP2™ from BASF Corp.), poly(styrene/maleic anhydride) and mixtures thereof. Preferably the average molecular weight of the polycarboxylate polymer sequestering agent is between about 500 to 500,000 daltons and preferably ranges from about 1,000 to about 200,000 daltons, more preferably from about 3,000 to about 70,000 daltons.
[0080] Most preferably the sequestering agent is selected from polyacrylic acid, a polyacrylic acid derivative, a copolymer of acrylic acid or methacrylic acid and a comonomer, which is maleic acid or maleic anhydride and mixtures thereof.
[heading-0081] Other Adjuncts
[0082] The disinfectant composition of the present invention may optionally be formulated to include further adjuncts, for example, thickening agents, rheology modifiers, fragrances, coloring agents, pigments (e.g., ultramarine blue), bleach-stable dyes (e.g., anthraquinone dyes), whiteners, including the optional surfactants, solvents, chelating agents and builders, which enhance performance, stability or aesthetic appeal of the composition. Generally, such adjuncts may be added in relatively low amounts, e.g., each from about 0.001 to about 5.0 weight percent of the composition. By way of example, a fragrance such as a fragrance commercially available from International Flavors and Fragrance, Inc., may be included in the inventive composition in an amount from about 0.01 to about 0.5 weight percent of the composition. Dyes and pigments may be included in small amounts, ultramarine blue (UMB) and copper phthalocyanines being examples of widely used pigments, which may be incorporated in the composition of the present invention.
[0083] Solvents may also be added to the inventive compositions to enhance cleaning and/or disinfectant efficacy of the compositions. For example, certain less water soluble or dispersible organic solvents, some of which are advantageously stable in the presence of hypochlorite bleach, may be included. These bleach-stable solvents include those commonly used as constituents of proprietary fragrance blends, such as terpenes and essential oils, and their respective derivatives.
[0084] The terpene derivatives suitable for the present invention include terpene hydrocarbons with a functional group. Effective terpenes with a functional group include, but are not limited to, alcohols, ethers, esters, aldehydes and ketones. Representative examples of each of the above-mentioned terpenes with a functional group include, but are not limited, to the following: (1) terpene alcohols, including, for example, verbenol, transpinocarveol, cis-2-pinanol, nopol, iso-bomeol, carbeol, piperitol, thymol, alpha-terpineol, terpinen-4-ol, menthol, 1,8-terpin, dihydroterpineol, nerol, geraniol, linalool, citronellol, hydroxycitronellol, 3,7-dimethyl octanol, dihydromyrcenol, beta-terpineol, tetrahydro-alloocimenol and perillalcohol; (2) terpene ethers and esters, including, for example, 1,8-cineole, 1,4-cineole, iso-bornyl methylether, rose pyran, alpha-terpinyl methyl ether, menthofuran, trans-anethole, methyl chavicol, allocimene diepoxide, limonene mono-epoxide, iso-bornyl acetate, nopyl acetate, alpha-terpinyl acetate, linalyl acetate, geranyl acetate, citronellyl acetate, dihydro-terpinyl acetate and neryl acetate; and (3) terpene aldehydes and ketones, including, for example, myrtenal, campholenic aldehyde, perillaldehyde, citronellal, citral, hydroxy citronellal, camphor, verbenone, carvenone, dihydrocarvone, carvone, piperitone, menthone, geranyl acetone, pseudo-ionone, alpha-ionone, beta-ionone, iso-pseudo-methyl ionone, normal-pseudo-methyl ionone, iso-methyl ionone and normal-methyl ionone. Terpene hydrocarbons with functional groups which appear suitable for use in the present invention are discussed in substantially greater detail by Simonsen and Ross, The Terpenes, Volumes I-V, Cambridge University Press, 2 nd Ed., 1947, which is incorporated herein in entirety by this reference. See also, commonly assigned U.S. Pat. No. 5,279,758, issued to Choy on Jan. 18, 1994, which is incorporated herein in entirety by this reference.
[heading-0085] Packaging Materials and Packaging Means
[0086] Suitable packaging materials may be provided by a variety of sources, and include all suitable materials that are hypohalite stable, in that they undergo no significant degradation, that is no significant chemical or physical change in structure, properties or form, owing to contact with the hypohalite compositions employed in the present invention. Suitable packaging materials include those materials common to the art.
[0087] Packaging means includes means for individually packaging the disinfectant wipes of the invention and means for bulk packaging one or more disinfectant wipes, or one or more individually packaged disinfecting articles. Such means includes those common to the art, such as tear open packets containing one or more individual disinfectant wipes and bulk dispensers such as canisters, tubs and containers that dispense one disinfectant wipe at a time and further feature suitable means to reseal the bulk dispenser between uses to preserve the integrity of the disinfecting articles. One example is a cylindrical canister dispenser that hosts a roll of individual wipes, separated by perforations to permit the tearing off of individual wipes for use. Such dispenser is conveniently gripped by the user and held in position while the user removes a wipe. Preferred are dispensers featuring a resealable dispensing cap and orifice (See, e.g., Chong, U.S. Pat. No. 6,554,156, of common assignment and incorporated herein by reference thereto) that dispenses individual wipes from a roll and retains the next wipe in a ready-to-dispense position, yet allows sealing of the dispensing cap to close the container against the environment when not in use. A further example, within the scope of the present invention, is to package individual wipes in a non-linked manner, in a dispenser permitting their removal one at a time—as is the case with many diaper wipe wipe/dispenser combinations known in the art.
[heading-0088] Methods for Determining the Desired Properties
[0089] Samples of the inventive disinfectant articles and those of commercially available bleach containing wipes were evaluated for activity using oxidation/reduction titration methods known to those in the art.
[0090] To assess the level of available disinfectant, the amount of available halogen oxidant on the disinfectant articles were determined by placing about 2 to 3 gram samples of the disinfecting wipe into about 50 milliliters of distilled water, followed by addition of about 10 milliliters of a 10 weight/weight percent solution of potassium iodide and addition of about 10 milliliters of a 10 volume percent solution of sulfuric acid, the resulting mixture being well stirred. The resulting purple solution, whose color is the result of oxidation of free iodine ion (1-) to molecular iodine (12), was then volumetrically titrated to an essentially colorless endpoint by addition of standardized 0.1 Molar sodium thiosulfate (Na 2 S 2 O 3 ) titrant. Calculations then express the result as percent of available active molecular chlorine (Cl 2 ), that is to say assigning two equivalents per mole of titrated hypohalite oxidant. Stability results are then expressed by repeated assays over time using identically prepared samples resulting from the same disinfectant solution and absorbent material, normalized to 100 percent representative of the starting available chlorine measured initially. This method allows fairly accurate assessment of the total amount of disinfectant absorbed onto their respective associated absorbent carrier materials.
EXAMPLES
[0091] Representative disinfecting compositions suitable for use on the disinfecting articles of the present invention are found in Table 1. Compositions are readily prepared by combining the ingredients in any order. Typically, addition of buffer/electrolyte materials is done in whole, if not in part, after addition of most other ingredients except water, to provide greater control and adjustment of the final composition pH.
Example A
[0092] The following disinfecting article, corresponding to Example A in Table 2, was prepared by dosing 2.75 grams of an aqueous solution containing about 0.55 weight % sodium hypochlorite, 0.05 weight % sodium lauryl sulfate and 0.32 weight % sodium hydroxide, per gram weight of a dry non-woven substrate from Polymer Group, Inc, designated 2006N, being a 100% spunlace polyester absorbent material capable of completely absorbing the applied solution without dripping.
Example B
[0093] Example B was prepared by dosing about 3.5 grams of the same composition employed in Example A, per gram weight of the same polyester material. In both Examples A and B, the absorbent material has an approximate basis weight of about 68 grams per square meter (gm −2 ), and a corresponding rectangle of the material having dimensions of approximately 7 inches by 8 inches was used to prepare the disinfecting article.
[heading-0094] Example C through H
[0095] Examples C through H were prepared in a similar fashion and using the same disinfectant solution as employed in Examples A and B, however, varying amounts of the solution were applied as required to achieve the gram/gram loading ratios as indicated in Table 2 using the corresponding absorbent materials as substrates as indicated in Table 2.
[heading-0096] Comparative Examples I through L
[0097] Comparative Example I through L were prepared in a similar fashion and using the same disinfectant solution as employed in Examples A and B, however, varying amounts of the solution were applied as required to achieve the gram/gram loading ratios as indicated in Table 2. It should be noted that the absorbent material employed in Comparative Examples I and J is a commercially available 100% spunbond polypropylene available from Rockline, having a basis weight of about 44 gm −2 . Absorbent material employed in Comparative Examples K and L is a commercially available 100% spunbond polypropylene from Kimberly-Clarke, having a basis weight of about 34 gm −2 . The disinfecting articles were prepared by using the corresponding absorbent materials as substrates as indicated in Table 2.
[heading-0098] Comparative Commercial Example
[0099] DISPATCH® Hospital Cleaner Disinfectant with Bleach pre-moistened towellete, available from Caltech Industries, was also evaluated for purposes of comparing versus the disinfectant articles of the current invention. It should be noted that the absorbent material employed in the DISPATCH towellete was identified as being an unmodified polypropylene polymer, a similar polymer as employed in Comparative Examples I through L above. The advantages of the present invention may clearly be seen by comparing the Examples of the present invention with the comparative examples and a leading commercially available disinfecting wipe.
[0100] Table 2 presents the stability of disinfectant articles prepared using a variety of selected polymer substrates, wherein examples A through H represent substrates used for the disinfectant absorbent carrier materials selected according to the requirements of the present invention. Comparative examples I through L employ the same aqueous disinfectant compositions as used in preparing example A, but employ substrates commonly used in commercial examples representative of the current state of the art, such as the DISPATCH® Hospital Cleaner Disinfectant with Bleach pre-moistened towellete, available from Caltech Industries. All examples prepared using the substrates of the present invention show improved stability and maintenance of an acceptable level of active disinfectant, even after test storage conditions chosen to represent accelerated ageing conditions.
[0101] The advantages of the present invention are also graphically presented in FIG. 1 . In FIG. 1 , Inventive Example I and Inventive Example 2 are disinfectant articles prepared using absorbent carrier materials selected according the requirements of the present invention. Comparative examples J and a commercial wipe (the Dispatch disinfectant wipe) are also shown with the results of accelerating ageing of representative samples for an extended time at a temperature of 120 degrees Fahrenheit to simulate the effects of extended storage. Also shown in FIG. 1 is the acceptable lower available chlorine limit (EPA limit 0.52%) suggested by the United States Environmental Protection Agency (US-EPA) for a disinfecting bleach wipe for purposes of registration for use on food contact and other surfaces. The advantages of disinfecting articles of the present invention are clearly seen over the current state of art in FIG. 1 in providing a disinfectant article with improved stability and the extended disinfect efficacy associated with said improved stability, even after prolonged storage under adverse storage times and temperatures.
TABLE 1 Aqueous hypohalite compositions Composition # Ingredient 1 2 3 4 5 6 Water (1) 98.90 99.055 98.73 99.00 98.11 97.55 Sodium hypochlorite (2) 0.70 0.70 0.55 0.55 1.50 1.84 Sodium hydroxide (3) 0.10 0.15 0.32 0.15 0.10 0.32 Surfactant A (4) 0.05 — — — — — Surfactant B (5) — 0.05 — — — 0.2 Surfactant C (6) — — 0.05 0.05 0.20 — Fragrance (7) 0.03 0.03 0.03 0.03 0.04 0.04 Chelant (8) 0.22 0.015 0.32 0.22 0.05 0.05 (1) Distilled or deionized water (2) Source is plant produced sodium hypochlorite diluted from high strength stock (3) Product of J. T. Baker (4) Sodium xylene sulfonate, anionic hydrotrope. (5) Lauryl amine oxide surfactant, product of Stepan Company (6) Sodium lauryl sulfate, anionic surfactant, product of Stepan Company (7) Perfume composition from Quest corporation (8) Sodium silicate solution from PQ Corporation
[0102] TABLE 2 Stability of Disinfectant Articles % Active Basis Loading % Active 1 Day % Active % Active System Substrate Weight Ratio Initial (6) 5 Days 11 Days (1) (2) (3) (4) (5) @ 120 F @ 120 F @ 120 F Inventive A PE2006N 68 2.75 100 98.6 94.3 80.0 Inventive B PE2006N 68 3.5 100 100 95.7 85.7 Inventive C PEM017 58 2.75 100 100 95.7 75.7 Inventive D PEM017 58 3.5 100 100 97.1 81.4 Inventive E HPE8010 45 2.75 100 100 91.4 75.7 Inventive F HPE8010 45 3.5 100 98.6 95.7 81.4 Inventive G HPE8005 68 2.75 100 —(7) 87.1 61.4 Inventive H HPE8005 68 3.5 100 —(7) 88.6 70.0 Comparative I PP Donut 44 2.75 100 97.1 54.3 trace (8) Comparative J PP Donut 44 3.5 100 95.7 44.3 trace (8) Comparative K PP 1.2 34 2.75 100 100 95.7 trace (8) Comparative L PP 1.2 34 3.5 100 100 97.1 trace (8) Dispatch (9) PP — ˜5 100 91.4 84.3 trace (8) (10) As Neat None — — 100 — — 54.3 solution (12) A-L (11) (1) System is absorbent substrate loaded at loading ratio with neat sodium hypochlorite solution (Composition 1 detailed in Table 1) (2) Substrates include 100% polyester (PE 2006N, PE M017) from Polymer Group Inc., 100% polyester (PE 8010) from Dupont, hydrophilically modified polyester (HPE 8005H) from Dupont, 100% polypropylene (PP donut) from Rockline, Inc. and 100% polypropylene (PP 1.2) from Kimberly-Clarke Corporation, each having basis weights as indicated in Column 3. Substrate size tested is 7″ × 8″ # size for Inventive examples A-H and 6″ × 6.75″ for comparative examples I-L. Dispatch Wipe is analyzed as being 100% polypropylene (PP). (3) Basis weight expressed in gram/m 2 (gm −2 ) (4) Loading ratio expressed in (unit less) ratio of applied composition weight/dry absorbent weight (5) % Active is the available chlorine measured via titration method described in the specification herein. Measured immediately following loading, unless stated otherwise. (6) % Active is the remaining available chlorine at indicated time, determined by assaying replicates stored in sealed cylindrical container away from light under constant temperature conditions at 120° F., unless otherwise noted. (7) Missed data point (8) Lower limit of detection corresponds to about 0.01 wt % active chlorine, or about 1.4% remaining activity, recorded as “trace.” (9) DISPATCH ® Hospital Cleaner Disinfectant with Bleach pre-moistened towellete, available from Caltech Industries. Substrate was identified as unmodified polypropylene polymer. Wipe size measured to be 7″ × 8″. (10) Measured immediately following opening of replicate representative Dispatch towelletes randomly selected from box lot. (11) Neat aqueous liquid disinfectant composition used for dosing absorbent carriers, corresponding to Example composition # 1 detailed in Table 1. (12) Neat aqueous liquid stored in similar liquid tight canister as where the disinfectant articles under identical storage conditions to serve as reference control.
Disinfectancy Contact Time
[0104] Table 3 presents disinfectancy tests results of the inventive disinfectant wipes used against three microorganisms, Staphylococcus aureus, Salmonella chloreaesuis and Pseudomonas aeruginosa , present on contaminated hard surfaces with 5% soil load, following test methodology suggested by the United States Environmental Protection Agency (US-EPA) to establish disinfectant efficacy of wipes. The results clearly indicate the superiority of the disinfectant articles of the present invention in achieving disinfectancy, that is 100% effective destruction of viable microorganisms, on soiled hard surfaces within 30 second exposure times, compared to the commercial Dispatch Wipes product that requires I full minute for disinfectancy.
TABLE 3 Minimum Contact Time for Disinfectant Efficacy against Microorganism Dispatch Inventive Microorganism (1) Wipe (2) Disinfectant Wipe (3) Staphylococcus aureus 1 min. 30 sec Salmonella chloreaesuis 1 min. 30 sec Pseudomonas aeruginosa 1 min. 30 sec (1) Selected microorganisms suggested by the United States Environmental Protection Agency for disinfectant spray testing on hard non-porous surface with 5% soil load (2) DISPATCH ® Hospital Cleaner Disinfectant with Bleach pre-moistened towellete, available from Caltech Industries. Label states a minimum level of 0.52 weight % active as sodium hypochorite. Minimum contact times effective for target organisms as stated on product master label. (3) Inventive disinfectant wipe corresponding to Composition # 3 (Table 1) with a 0.55 weight % sodium hypochlorite loaded onto a 100% polyester substrate.
[0105] Without departing from the spirit and scope of this invention, one of ordinary skill can make various changes and modifications to the invention to adapt it to various usages and conditions. As such, these changes and modifications are properly, equitably, and intended to be, within the full range of equivalence of the following claims. | The present invention relates to disinfecting articles and wipes saturated with an aqueous hypohalite composition with improved stability and extended efficacy for cleaning and disinfecting surfaces against harmful and infectious pathogens. The wipe substrate is selected from hypohalite stable materials that do not catalyze decomposition of the associated aqueous hypohalite releasing compositions. The disinfectant articles provide a minimum disinfecting level of active hypohalite for an extended time, ensuring reliably disinfection of hard surfaces such as countertops, toilet seats, door knobs and the like commonly found in the home, hospital, food service and other industries. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention is directed to a manually operated dispensing pump and more particularly to a finger-operated pump adapted for mounting on a container of liquid to be dispensed.
2. Brief Description of Background Art
Container-mounted, finger-operated dispensing pumps are well known and are used for dispensing liquids having widely varying flow characteristics. The form of discharge from these pumps can vary from a fine spray to a slow moving flow.
Typically, container-mounted dispensing pumps employ fixed and movable pump members forming a variable volume pump chamber and one-way valves controlling the flow into and out of the pump chamber. Various types of one-way valves, including ball check valves and elastomeric valves, are employed in these dispensing pumps.
A dispensing pump disclosed in U.S. Pat. No. 3,406,909 issued to Pfeiffer employs elastomeric one-way valves, known as "duckbill" valves, for controlling flow into and from the pump chamber. These valves operate reliably and are relatively inexpensive. Their one-piece construction simplifies the assembly of a dispensing pump in which they are employed.
Many dispensing pumps incorporate a feature which allows them to be placed in a "shipping" position to prevent leakage through the pump if they are upended. A common pump of this type employs a reciprocable plunger which can be locked in a depressed position to seal the pump against leakage. Applicants are not aware of dispensing pumps employing duckbill pump valves which can be placed in a shipping position to prevent leakage through the pump.
OBJECTS OF THE INVENTION AND SUMMARY
An object of the present invention is to provide a dispensing pump which operates reliably and which is inexpensive to manufacture.
Another object of the present invention is to provide a dispensing pump employing elastomeric duckbill pump valves.
Yet another object of the present inventions to provide a container-mounted dispensing pump incorporating a positive closing mechanism for a duckbill pump valve which precludes leakage of the container contents through the pump.
The foregoing objects of the invention, and others as well, are realized in the dispensing pump of the present invention which incorporates movable and stationary pump members forming a variable volume pump chamber, at least one elastomeric duckbill valve controlling the flow of liquid into or from the pump chamber and movable pinching elements for applying a positive closing force to a duckbill valve to prevent leakage through the pump. In disclosed embodiments of the present invention, the pinching elements are hinged and cooperate with the movable pump member to apply a positive closing force to the tip of a duckbill valve when the movable pump member is disposed in a depressed, shipping position.
The detailed description provided below together with the accompanying drawings will afford a further understanding of the present invention. Specific embodiments of the present invention which are disclosed herein should be regarded as illustrative and not restrictive of the scope of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross-sectional view of a dispensing pump constructed according to the teachings of the present invention, showing the pump plunger in an extended position.
FIG. 2 is a cross-sectional view of the dispensing pump illustrated in FIG. 1, showing the pump plunger in a depressed position.
FIG. 3 is an isometric illustration of a valve-closing device employed in the dispensing pump illustrated in FIGS. 1 and 2.
FIG. 4 is a cross-sectional view of another embodiment of a dispensing pump constructed according to the present invention, showing the pump plunger in an extended position.
FIG. 5 is a cross-sectional view of the dispensing pump illustrated in FIG. 4, showing the pump plunger in a depressed position.
FIG. 6 is an isometric cross-sectional view of the stationary pump member of the dispensing pump illustrated in FIGS. 4 and 5.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Referring to FIGS. 1, 2, and 3, a dispensing pump incorporating the present invention includes a pump body 10 provided with an internal annular wall 11 forming a well which accommodates stationary and movable pump members 20 and 30 which together form a variable volume pumping chamber. An internally threaded skirt 12, formed integrally with the pump body, provides a means for attachment of the dispensing pump to the threaded neck of a container (not shown) of liquid to be dispensed.
The stationary pump member 20, a tubular piston, is fixed at its lower end in an inturned flange 13 formed at the lower end of annular wall 11. A diptube 21 for conducting liquid to the pump chamber is fitted within the lower end of stationary piston 20. At its upper end the piston is enlarged and bell-shaped and terminates in a sealing lip
The movable pump member 30, or plunger, fits within annular wall 11 of pump body 10 and surrounds stationary piston 20. The interior wall surface of the plunger engages the lip 22 of the piston, forming therewith a sliding seal. Adjacent the lower end of plunger 30, on the exterior surface thereof, an annular seal 31 is provided, of a size to engage the interior surface of annular wall 11 to form therewith a sliding seal, for a purpose to be subsequently described. At its upper end, the plunger carries a dispensing head 40 fitted with a discharge nozzle 41.
Seated on an internal shoulder within the bell-shaped upper end of the stationary piston 20 is a one-way inlet valve 23. More specifically, valve 23 is a hollow elastomeric one-way valve commonly known as a "duckbill" valve. This valve has a ring-like base and inwardly tapering sidewalls terminating in a tip provided with a normally closed slit passage.
Surrounding the base of the valve and retained by a bead 24 formed on the interior surface of the bell-shaped upper end of the stationary piston 20 is a fitting 25 provided with hinged pinching elements or leaves 26 which can be moved into pinching engagement with the tip of the inlet valve 23 to thereby positively close the slit passage of the valve. (Details of fitting 25 are best shown in the enlarged illustration of FIG. 3.) Leaves 26 are of generally L-shaped cross-section, and each is provided with a camming shoulder 27.
A one-way outlet valve 32, which may be an elastomeric duckbill valve as shown, is supported on a formation 33 provided in the upper end of the plunger 30. A skirt 34 depends from formation 33. The lower free end of skirt 34 is provided with an internal annular bevel 35 adapted to engage the camming shoulders 27 on leaves 26 to pinch the inlet valve 23 closed when the movable pumping element is disposed in its lowermost position.
The plunger is biased upwardly to an extended position, shown in FIG. 1, by a spring 14 seated on the inturned flange 13 at the bottom of annular wall 11 of the pump body 10. In this position, the volume of the pump chamber bounded by the stationary piston and plunger and the one-way inlet and outlet valves is at its maximum. Downward pressure on the dispensing head will shift the cylinder toward the position shown in FIG. 2 in which the volume of the pump chamber is at its minimum. In this position, the annular bevel 35 on the lower end of skirt 34 engages the camming shoulders 27 of pinching elements 26, pressing them inwardly into pinching engagement with the slitted tip of inlet valve 23.
An upstanding collar 15 formed integrally with the pump body has an interior surface which is a continuation of the interior surface of internal annular wall 11. Formed on the interior surface of the collar is a longitudinally extending groove 16 having an open end at the upper edge of the collar 15. Extending through the lower inturned end 13 of annular wall 11 are one or more passages 17. The groove 16 and the passages 17 together establish a venting passage between the surrounding atmosphere and the interior headspace of a container on which the dispensing pump is mounted. The venting passage is open or closed depending on the position of the plunger 30. In the uppermost, extended, position of the plunger, as shown in FIG. 1, the annular seal 31 formed on the lower end of the plunger is positioned above the lower closed end of groove 16 to establish an open condition of the venting passage. In the lowermost, depressed, position of the plunger 30, as shown in FIG. 2, the annular seal 31 is positioned below the lower closed end of groove 16 to close the venting passage. Obviously, the groove 16 could be made longer if desired to maintain the open condition of the venting passage over a greater portion of the travel of the plunger.
An external thread formation 18 provided on the outer surface of collar 15 is adapted to mate with an internal thread formation 43 provided on the lower interior surface of a skirt 42 which is part of the dispensing head 40. Coupling of the thread formations 18, 43, which places the dispensing pump in a shipping position, can be effected at the lowermost, depressed, position of the plunger 30, as shown in FIG. 2. To enable the relative rotation between dispensing head 40 and collar 15 which is necessary to bring about coupling of the thread formations 18, 43, the dispensing head 40 may be rotatably joined to plunger 30 and/or the plunger may be rotatably disposed within pump body 10.
In the embodiment of the invention shown in FIGS. 1 and 2, the hinged pinching elements 26 are part of a fitting seated on a flange formed at the bottom of the duckbill inlet valve 23 and retained by a bead 24 (or projections) formed on the interior surface of the enlarged upper end of the stationary piston 20. As shown in greater detail in FIG. 3, the pinching elements 26 are joined by integral strap hinges 28 to a split-ring base 29. Flat segments 29a on the interior surface of the base match the flat tapering sidewalls of the duckbill valve as an aid to orienting the fitting 25 over the valve during assembly. Fitting 25 is preferably molded from a resilient plastic material. The gap in the split-ring base 29 allows yielding of the base as it is inserted past the retaining ring 24 in the enlarged upper end of the stationary piston 20.
Another, presently preferred, dispensing pump constructed according to the present invention is illustrated in FIGS. 4, 5 and 6. Referring particularly to FIG. 6, which shows in cross-section the upper end of modified stationary piston 50, the pinching leaves 56 are generally flat and are joined by integral hinges 58 to the radially inner top edge of the bell-shaped upper end of the stationary piston 50.
As shown in FIGS. 4 and 6, the free inner ends of the leaves 56 are spaced from the tip of the inlet duckbill valve 23 when the plunger 60 is disposed in its upper, extended, position. A bevel 57 is formed on the upper surface of each pinching leaf 56 adjacent its hinge 58. As in the embodiment illustrated in FIGS. 1 and 2, one-way outlet valve 32, which may be an elastomeric duckbill valve as shown, is seated in the upper end of the plunger 60. A skirt 64 depends from the seat 63 for the outlet valve 32. An internal annular bevel 65 formed on the lower free end of the skirt 64 is adapted to engage the bevel 57 formed on each pinching leaf when plunger 60 is disposed in its lowermost, shipping position.
As shown in FIG. 5, the engagement of the bevel 65 of skirt 64 with the bevels 57 on the pinching leaves 56 deflects the leaves downwardly so that the inner free ends of the leaves pinch and close the tip of inlet valve 23. As in the embodiment shown in FIGS. 1 and 2, threads 18, 43, provided respectively on the outer surface of collar 15 and on the lower interior surface of a skirt 42 which is part of the dispensing head 40, may be engaged to secure the plunger in the lowermost shipping position. This embodiment also employs the venting arrangement employed in the embodiment of FIGS. 1 and 2.
Both disclosed embodiments of a dispensing pump constructed according to the teachings of the present invention employ a fixed pump member in the form of a piston and a movable pump member in the form of a plunger fitting about the piston. Without departing from the present invention, this arrangement may be transposed so that the fixed pump member is a cylinder receiving a movable piston, or plunger. In the resulting dispensing pump, a pinching mechanism, similar to the mechanism employed in the embodiment illustrated in FIGS. 1 and 2 may be employed to close the inlet duckbill valve when the plunger is disposed in its lowermost position.
Various modifications of the present invention may be obvious to persons of ordinary skill in the art having the benefit of this disclosure. All such modifications are to be regarded as falling within the scope of the invention as defined in the following claims. | A container-mounted dispensing pump incorporates elastomeric duckbill valves for controlling the flow into and from the pump chamber. A mechanism within the pump employs hinged leaves which cooperate with the pump plunger to effect a pinching and closing one of the duckbill valves when the plunger is disposed in a depressed, shipping position. With the pump plunger held in the shipping position, the closed duckbill valve will preclude leakage of the container contents through the pump. | 1 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of U.S. provisional application Ser. No. 60/529,876, filed 16 Dec. 2003, entitled “Suppression of Stimulated Brillouin Scattering in Optical Fibers Using Fiber Bragg Gratings,” (Attorney Docket: 315-003us), which is incorporated by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to optics in general, and, more particularly, to techniques for mitigates the effects of Stimulated Brillouin Scattering in electromagnetic waveguides such as optical fibers.
BACKGROUND OF THE INVENTION
[0003] Stimulated Brillouin scattering occurs when the signal power in an optical fiber reaches a level that can generate acoustic vibration in the glass, corresponding to powers as low as a few milliwatts in the small cores of single-mode fiber. Acoustic waves change the density of a material and thus alter its refractive index. The resulting fluctuations in refractive index can scatter light; this effect is called Brillouin scattering. Because the light wave being scattered itself generates the acoustic waves, the process in fibers is called stimulated Brillouin scattering.
[0004] In single-mode fibers, stimulated Brillouin scattering is manifested as the generation of a backward-propagating Stokes wave, downshifted slightly in frequency from the original light wave. (For example, the frequency shift is 11 GHz, or slightly less than 0.1 nanometers, for an incident wave that has a wavelength of 1500 nm.) The scattered wave goes back toward the transmitter, and increases in intensity along the length of the fiber due to accumulation of stimulated Brillouin scattering. The effect is strongest when the light pulse is long (allowing a long interaction between light and the acoustic wave), and the laser linewidth is very small, around 100 MHz. Under continuous-wave conditions, it can occur at power levels as little as 3 mW for sufficiently long fibers.
[0005] Brillouin scattering reduces signal strength by directing part of the light back toward the transmitter, effectively increasing attenuation. Careful design can reduce the impact of Brillouin scattering, but Brillouin scattering sets an upper limit for power levels in systems using narrow-linewidth laser sources. The strength of the effect of Brillouin scattering can increase with the number of optical amplifiers in a system. Optical isolators can be added to block light from going toward the transmitter to block that increase, but at the cost of added system complexity and expense.
[0006] Stimulated Brillouin scattering has been studied extensively in the context of optical communications systems, but it also impacts the performance of high-power fiber lasers and amplifiers designed to generate Q-switched pulses with high energies. Although fiber lengths are not very large in the case of fiber lasers and amplifiers, the peak power of a Q-switched pulse can exceed 10 kW. The effects of stimulated Brillouin scattering can be mitigated, to some extent, by reducing pulse duration below 10-20 nanoseconds; however, the transient nature of stimulated Brillouin scattering continues to play an important role for such short pulses.
SUMMARY OF THE INVENTION
[0007] The present invention provides a mechanism for mitigating the effects of Stimulated Brillouin Scattering in electromagnetic waveguides such as optical fibers without some of the costs and disadvantages for doing so in the prior art.
[0008] In particular, the illustrative embodiment of the present invention incorporates a plurality of evenly-spaced wavelength-selective mirrors, such as fiber Bragg gratings, into the waveguide that are designed to convey a forward-propagating incident wave and to reflect the backward-propagating Stokes wave induced by the incident wave. This prevents the build up of the backward-propagating Stokes wave and mitigates the deleterious effects of Stimulated Brillouin Scattering.
[0009] The illustrative embodiment of the present invention comprises: an electromagnetic waveguide that is capable of transporting a first electromagnetic wave in one direction and a second electromagnetic wave in the opposite direction, wherein the second electromagnetic wave is stimulated by the first electromagnetic wave; and an wavelength-selective mirror in the electromagnetic waveguide that reflects the second electromagnetic wave more than the first electromagnetic wave.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 depicts a block diagram of the salient components of a telecommunications system in accordance with the illustrative embodiment of the present invention.
[0011] FIG. 2A depicts a representational drawing of the salient aspects of optical fiber 200 -A in accordance with the illustrative embodiment.
[0012] FIG. 2B depicts a representational drawing of the salient aspects of optical fiber 200 -B, which is an optical fiber in accordance with some embodiments of the present invention.
[0013] FIG. 2C depicts a representational drawing of the salient aspects of optical fiber 200 -C, which is an optical fiber in accordance with some embodiments of the present invention.
[0014] FIG. 3 depicts an enlarged representational drawing of the salient aspects of optical fiber 200 -B.
[0015] FIG. 4A depicts a graphical representation of the intensity of a Stokes wave in optical fiber 202 A as it increases in intensity in the five sections separated by the three fiber Bragg gratings.
[0016] FIG. 4B depicts a graphical representation of the intensity of a Stokes wave in an optical fiber comprising a single fiber Bragg grating, located near the transmitter end of the optical fiber.
[0017] FIG. 5 depicts a schematic drawing of the salient aspects of a fiber laser in accordance with some embodiments of the present invention.
DETAILED DESCRIPTION
[0018] FIG. 1 depicts a block diagram of the salient components of a telecommunications system in accordance with the illustrative embodiment of the present invention. Telecommunications system 100 comprises eleven geographically-distributed telecommunications switches 101 - 1 through 101 - 11 and a plurality of electromagnetic waveguides that interconnect some pairs of telecommunications switches. The ability of telecommunications system 100 to operate is based upon, among other things, the ability of the electromagnetic waveguides to carry electromagnetic waves from one telecommunications switch to another without much loss or distortion.
[0019] In accordance with the illustrative embodiment, the electromagnetic waveguides are optical fibers. It will be clear to those skilled in the art, however, after reading this disclosure, how to make and use alternative embodiments of the present invention in which the electromagnetic waveguides are something other than optical fibers (e.g., metallic co-axial cable, microstrip transmission lines, etc.).
[0020] In accordance with the illustrative embodiment, each of telecommunications switches 101 - 1 through 101 - 11 uses a high-power laser to transmit a 1550 nm-wavelength optical bit stream with more than 10 mW of average power in an optical fiber. Many telecommunications systems in the prior art use lasers of significantly less power. In this case, the high-power wave is advantageous because it provides a high signal-to-noise ratio at the receiver and does not need to be re-generated in such a short distance as a lower-power wave.
[0021] It will be clear to those skilled in the art, after reading this specification, how to make and use alternative embodiments of the present invention that use lasers of different powers and pulses of different widths. Furthermore, it will be clear to those skilled in the art, after reading this specification, how to make and use alternative embodiments of the present invention that transmit an optical wave with any wavelength.
[0022] As is well-known to those skilled in the art, the high-power optical wave induces Stimulated Brillouin Scattering in the optical fibers, which manifests itself as a backward-propagating Stokes wave, downshifted in frequency, in the direction opposite to the inducing wave. The illustrative embodiment of the present invention mitigates the effect of Stimulated Brillouin Scattering by inserting a wavelength-selective mirror in the optical fiber, as depicted in FIG. 2A through 2C .
[0023] FIG. 2A depicts a representational drawing of the salient aspects of optical fiber 200 -A, in accordance with the illustrative embodiment of the present invention. Optical fiber 200 -A is capable of transporting a forward-propagating incident wave in a forward direction and of transporting the backward-propagating Stokes wave in the backward direction.
[0024] Optical fiber 200 -A comprises a plurality of evenly-spaced fiber Bragg gratings, such as fiber Bragg grating 201 -A, along the entire length of optical fiber 200 -A and that reflects the backward-propagating Stokes wave more than it does the forward-propagating incident optical wave (i.e., the coupling coefficient of the grating is greater for the backward-propagating Stokes wave than the forward-propagating incident optical wave). The number of and spacing between fiber Bragg gratings 201 -A governs the intensity of the backward-propagating Stokes wave that exists in optical fiber 200 -A. Although the illustrative embodiment comprises six fiber Bragg gratings, it will be clear to those skilled in the art, after reading this specification, how to make and use alternative embodiments of the present invention that comprise any number of fiber Bragg gratings. The details of optical fiber 200 -A are described in detail below and with respect to FIG. 3 .
[0025] FIG. 2B depicts a representational drawing of the salient aspects of optical fiber 200 -B in accordance with some alternative embodiments of the present invention. Optical fiber 200 -B is capable of transporting a forward-propagating incident wave in a forward direction and of transporting the backward-propagating Stokes wave in the backward direction.
[0026] Optical fiber 200 -B comprises a wavelength-selective mirror that reflects the backward-propagating Stokes wave more than it does the forward-propagating incident optical wave. In particular, the wavelength-selective mirror is a fiber Bragg grating that comprises a plurality grating elements 201 -B along the entire length of the optical fiber 200 -A. It will be clear to those skilled in the art how to make and use optical fiber 200 -B and grating elements 201 -B for any wavelength and power of incident wave.
[0027] Optical fiber 200 -B is more expensive to manufacture than optical fiber 200 -A because it comprises more Bragg grating elements, but might be, in some cases, more effective than optical fiber 200 -A in mitigating the Stimulated Brillouin Scattering. In any case, it will be clear to those skilled in the art how to make and use optical fiber 200 -B and fiber Bragg grating 200 -B for any wavelength and power of incident wave.
[0028] FIG. 2C depicts a representational drawing of the salient aspects of optical fiber 200 -C, which is an optical fiber in accordance with some embodiments of the present invention. Optical fiber 200 -C is capable of transporting a forward-propagating incident wave in a forward direction and of transporting the backward-propagating Stokes wave in the backward direction.
[0029] Optical fiber 200 -C comprises a plurality of evenly-spaced chirped fiber Bragg gratings, such as chirped fiber Bragg grating 201 -C, that reflects the backward-propagating Stokes wave more than it does the forward-propagating incident optical wave. As is well known to those skilled in the art, chirped fiber Bragg grating 201 -C has a broader bandwidth than a non-chirped fiber Bragg grating. In any case, it will be clear to those skilled in the art, after reading this disclosure, how to make and use optical fiber 200 -C and chirped fiber Bragg grating 200 -C for any wavelength and power of incident wave.
[0030] FIG. 3 depicts an enlarged representational drawing of the salient aspects of fiber Bragg grating 201 -A, in accordance with the illustrative embodiment of the present invention. FIG. 3 depicts four grating elements G 1 through G 4 that are interleaved with three transmissive elements T 1 through T 3 , as shown. Each grating element and transmissive element has a width and an index of refraction that is designed to block the backward-propagating Stokes wave and yet pass the forward-propagating incident wave.
[0031] It will be clear to those skilled in the art how to determine the wavelength of the backward-propagating Stokes wave based on the wavelength, modulation rate, and power of the forward-propagating incident wave. Furthermore, it will be clear to those skilled in the art how to make and use fiber Bragg grating 201 -A for any wavelength of Stoke wave and incident wave.
[0032] FIG. 4A depicts a graphical representation of the intensity of a Stokes wave in optical fiber 202 A as it increases in intensity in the five sections separated by the three fiber Bragg gratings. At each fiber Bragg grating, the backward-propagating Stokes wave is reflected, thereby halting its accumulation in the backward-propagating direction and suppressing its intensity.
[0033] FIG. 4B depicts a graphical representation of the intensity of a Stokes wave in an optical fiber comprising a single fiber Bragg grating, located near the transmitter end of the optical fiber. Due to the longer length of optical fiber in which the backward-propagating Stokes wave accumulates, the intensity level of the Stokes wave reaches a higher level than that shown in FIG. 4A . In order to suppress the intensity of the Stokes wave, therefore, the coupling coefficient (a function of the grating modulation depth, grating length, grating period, and grating element width) of the fiber Bragg grating is higher than in the distributed grating case.
[0034] FIG. 5 depicts a schematic drawing of the salient aspects of a fiber laser in accordance with some embodiments of the present invention. Fiber laser 500 comprises Q-switched laser 504 , optical fiber 505 , amplification fiber coil 506 , and a plurality of evenly-spaced fiber Bragg gratings 201 -A.
[0035] Q-switched laser 504 , which operates at 1053 nanometer wavelength, launches optical pulses into optical fiber 505 . Amplification fiber coil 506 , which is a one-meter long optical fiber that is doped with ytterbium, is coupled to optical fiber 505 such that it provides optical gain to the optical power launched at the fiber laser output. Fiber Bragg gratings 201 -A suppress stimulated Brillouin scattering in amplification fiber coil 506 , thereby enabling the peak power of the amplified pulses to exceed 1 kW.
[0036] It will be clear to those skilled in the art, after reading this specification, how to make and use alternative embodiments of the present invention that use amplification fiber coils that are doped with materials other than ytterbium, such as erbium, yttrium, lanthanum, samarium, cerium, praseodymium, neodymium, promethium, europium, terbium, holmium, or thulium. Furthermore, it will be clear to those skilled in the art, after reading this specification, how to make and use alternative embodiments of the present invention that use amplification fiber coils of any length. And still furthermore, it will be clear to those skilled in the art, after reading this specification, how to make and use alternative embodiments of the present invention amplification fiber coil 506 comprises any manner or number of fiber Bragg gratings.
[0037] It is to be understood that the illustrative embodiments merely depict some contexts, applications, and combinations of the present inventions and that those skilled in the art can devise many variations of the illustrative embodiments without departing from the scope of one or more of the inventions. It is therefore intended that such variations be included within the scope of the following claims and their equivalents. | A mechanism for mitigating the effects of Stimulated Brillouin Scattering in electromagnetic waveguides such as optical fibers is disclosed. In particular, the illustrative embodiment of the present invention incorporates a plurality of evenly-spaced wavelength-selective mirrors, such as fiber Bragg gratings, into the waveguide that are designed to convey a forward-propagating incident wave and to reflect the backward-propagating Stokes wave induced by the incident wave. This prevents the build up of the backward-propagating Stokes wave and mitigates the deleterious effects of Stimulated Brillouin Scattering | 7 |
FIELD OF THE INVENTION
The present invention relates generally to an air or gas dryer. More particularly, the present invention relates to a method and apparatus for drying air used in pneumatic tools.
BACKGROUND OF THE INVENTION
Pneumatic tools use compressed air to provide power to the tool. Pneumatic tools are often made of metal components that are susceptible to rust or other corrosion when in contact with moisture. As a result, it is desired that the air used in the pneumatic tools have the moisture in the air removed as much as is practical. Often air used in pneumatic systems may be dried using desiccants. However, when a dew point is over 32° F. mechanical refrigeration is often used. Mechanical refrigeration cools the air which then lowers the dew point. As the air cools, the moisture in the air will condense. The condensate can be separated from the air. The air is then heated back up to a desired temperature. Thus heated air is considered a dry or dried air due to the fact that moisture originally found in that air has been removed. Standard mechanical refrigeration apparatuses involve high energy using components, such as, a compressor to compress a refrigerant which is later expanded as part of the refrigeration cycle. In addition, the use of refrigerants may be undesirable due to potential environmental harm that may occur should the refrigerant leak. Further, mechanical refrigeration systems include many moving parts which wear and need to be maintained and/or replaced over time. As a result, it may be desired to dry air by cooling it and re-heating it without the use of a typical mechanical refrigeration system.
Accordingly, it is desirable to provide a method and apparatus that can cool and reheat air without the use of mechanical refrigeration systems.
SUMMARY OF THE INVENTION
The foregoing needs are met, to a great extent, by the embodiments of the present invention. Wherein in one aspect an apparatus is provided that in some embodiments provides cooling and in some embodiments heating of air and or to dry the air without the use of typical mechanical refrigeration systems.
In accordance with one embodiment of the present invention, a gas dryer is provided. The gas dryer includes a first opening; structure forming a cooling pathway fluidly connected to the first opening; a first thermoelectric device thermally connected to the structure forming the cooling pathway and a heat exchanger; a condensate drain located near an end of the cooling pathway and configured to drain condensate formed when a fluid is cooled along the cooling pathway; a structure forming a warming pathway located between the condensate drain and a second opening; and a second thermoelectric device thermally connected between the structure forming cooling pathway and the structure forming the warming pathway and connected to exchange heat between the cooling pathway and the warming pathway.
In accordance with another embodiment of the present invention, a method of drying a gas is provided. The method includes: directing the gas through a cooling pathway; removing heat from the gas in the cooling pathway with a first thermoelectric device to a heat exchanger; condensing a fluid out of the gas; draining the condensed fluid from the gas; directing the gas though a warming pathway;
removing heat from gas in the cooling pathway with a second thermoelectric device and inserting that heat into gas in the warming pathway.
In accordance with yet another embodiment of the present invention, a gas dryer is provided. The gas dryer includes a first opening; structure forming a cooling pathway fluidly connected to the first opening; a first means for moving heat device thermally connected to the structure forming the cooling pathway and a heat exchanging means; a means for draining a liquid located near an end of the cooling pathway and configured to drain condensate formed when a fluid is cooled along the cooling pathway; a structure forming a warming pathway located between the means for draining a fluid and a second opening; and a second means for moving heat thermally connected between the structure forming cooling pathway and the structure forming the warming pathway and connected to exchange heat between the cooling pathway and the warming pathway.
There has thus been outlined, rather broadly, certain embodiments of the invention in order that the detailed description thereof herein may be better understood, and in order that the present contribution to the art may be better appreciated. There are, of course, additional embodiments of the invention that will be described below and which will form the subject matter of the claims appended hereto.
In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of embodiments in addition to those described and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein, as well as the abstract, are for the purpose of description and should not be regarded as limiting.
As such, those skilled in the art will appreciate that the conception upon which this disclosure is based may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side view of an air or gas dryer according to an embodiment of the invention.
FIG. 2 is an exploded perspective view of the gas dryer shown in FIG. 1 .
FIG. 3 is an enlarged perspective view of some of the components of the air dryer shown in FIGS. 1 and 2 .
FIG. 4 is a schematic diagram showing various components of the gas dryer and how the gas flows through the gas dryer.
DETAILED DESCRIPTION
Example embodiments of the invention will now be described with reference to the drawing figures, in which like reference numerals refer to like parts throughout. An embodiment in accordance with the present invention provides a gas dryer.
FIG. 1 illustrates an example embodiment of a gas dryer 10 . A gas dryer 10 may include a housing 11 . The housing 11 may be metal, plastic, or any other suitable substance. The housing 11 provides protection for the interior components of the gas dryer 10 .
According to some embodiments of the invention, the gas dryer 10 includes an air inlet 12 . The gas dryer 10 includes a chiller extrusion 13 . The chiller extrusion 13 maybe made of metal, such as aluminum. In some embodiments the chiller extrusion 13 is made of extruded aluminum. The gas dryer 10 also includes a heat exchanger 14 . The heat exchanger 14 may be a fin heat exchanger which includes fins 16 . Opposite the fins 16 on to the heat exchanger 14 is a hot side 18 which is abutted against a thermal electric device (TE device) 20 .
The chiller extrusion 13 terminates with a separator 22 . A separator 22 includes a separator bowl 24 and a separator end cap 26 . Located on the opposite side of the chiller extrusion 13 is a heating extrusion 30 .
In some embodiments of the invention, the heating extrusion 30 may also be made of extruded aluminum. In other embodiments of the invention, the heating extrusion 30 may be interchangeable and identical to the chiller extrusion 13 , the only difference being placement within the gas dryer 10 . In other embodiments of the invention the heating extrusion 30 may be different than the chiller extrusion 13 . The heating extrusion 13 connects to an outlet 32 . While the chiller and heating extrusion 13 and 30 are referred to herein as extrusions it is understood that the extrusions 13 and 30 are not limited to actually extruded parts, but may include parts that provide cooling and heating pathways made by any suitable technique.
In some embodiments of the invention compressed air or other gas is provided to the inlet 12 as shown by arrow A. The compressed air flows through one or more pathways defined by the chiller extrusion 13 . The gas or compressed air flows through the chiller extrusion 13 . The TE device 20 is provided electric current which causes the TE device on the side facing the chiller extrusion 13 to be cold and the side of the TE device 20 facing the heat exchanger 14 to be hot. Heat is transferred from the gas in the chiller extrusion 13 , into the cool side of the TE device 20 , and then eventually to the heat exchanger 14 and to the fins 16 of heat exchanger. The heat is then dissipated into the ambient air surrounding the gas dryer 10 .
As the air or gas flows through the chiller extrusion 13 and cools, moisture condenses and the condensate flows into the separator 22 . After the air is dried by the moisture condensing and draining into the separator 22 the air or gas flows into the heating extrusion 30 . In the heating extrusion, the air or gas is re-heated and then finally is let out of the outlet 32 is indicated by arrow B.
FIG. 2 shows and exploded view of the gas dryer 10 . As shown in FIG. 2 the heat exchanger 14 has a hot side 18 and on the opposite side are fins 16 . The heat exchanger 14 allows heat from the hot side to flow into the fins 16 where the fins 16 contact the ambient air of the gas dryer 10 and dissipate the heat. The hot side 18 includes a flat side 33 which abuts against the TE device 20 . As shown in FIG. 2 , the TE device 20 includes several TE chips 36 . While four TE chips 36 are shown, the TE device 20 may include any number of TE chips 36 , from one to any desired number. The TE chips 36 may be Peltier devices. One of ordinary skill in the art understands a Peltier device to operate in such a manner such that when provided a voltage, one side gets hot and the other side of the Peltier device gets cold. The TE device 20 is situated so the cold side of the TE chips 36 abuts against the chiller extrusion 13 , when the hot side abuts against the flat surface 33 of the heat exchanger 14 .
The separator 22 is comprised of a separator bowl 24 and a separator end cap 26 . A separator bowl 24 and a separator end cap 26 may be screwed together by threads 35 . The separator 22 may attach to both the chiller extrusion 13 and the heating extrusion 30 by separator screws 42 .
Insulation 38 , may be located in between the chiller extrusion 13 and the heating extrusion 30 . Hole 40 in the insulation 38 is provided and a second TE device 20 is located within the hole 40 . The second TE Device 20 may also include multiple TE chips 36 . TE chips 36 are oriented so that the cold side of the chip 36 is located against the flat side 34 of the chiller extrusion 13 and the hot side of the TE chips 36 is located against the heating extrusion 30 .
The outlet 32 is located in an outlet manifold 44 , which may be attached to the heating extrusion 30 by cap screws 46 . The inlet 12 is part of an inlet manifold 48 which may attach to the chiller extrusion 13 by cap screws 50 . Arrows A and B illustrate the direction of air or gas entering A and exiting B in gas dryer 10 .
FIG. 3 is a partial close-up view of the chiller extrusion 13 and the TE device 20 including the TE chips 36 . The chiller extrusion 13 includes threaded holes 52 which allow the cap screws 50 as shown in FIG. 2 to attach the inlet manifold 48 to the chiller extrusion 30 . The chiller extrusion 30 also includes multiple passage ways 54 . The passage ways are shown as various slots which allow the air or gas to flow through the chiller extrusion 13 . In some embodiments of the invention, the passage ways 54 may be more or fewer than as shown and may have a variety of different shapes. In the embodiment shown in FIG. 3 and the passage ways 54 are rectangular in cross-section and extend through the length of the chiller extrusion 13 . In other embodiments the passage ways 54 may have other cross-sectional shapes. Preferably the shapes of the passageways 54 are selected to promote heat transfer.
As mentioned above, the heating extrusion 30 may be interchangeable and thus identical in size and dimension and composition as the chiller extrusion 13 . Therefore, the description given with respect to the chiller extrusion 13 may also apply to the heating extrusion 30 . One of ordinary skill in the art would understand that the threaded holes 52 would allow the outlet manifold 44 to attach to the heater extrusion 30 in a matter similar to that discussed above with respect to the inlet manifold 48 attaching it to the chiller extrusion 13 with the cap screws 50 .
The chiller extrusion 13 also includes a flat surface 34 as discussed above. Also shown in FIG. 3 is the TE device 20 comprising multiple TE chips 36 . When the TE device 20 is located against the chiller extrusion 13 or, as indicated in FIG. 2 , against the heating extrusion 30 , a heat transfer paste may be applied to either or both of the extrusions 13 and 30 and the TE device 20 to facilitate heat transfer between the extrusions 13 and 30 and the TE device 20 . A heat transfer paste may also be placed between the TE device 20 and the flat side 33 of the heat exchanger 14 , shown in FIG. 2 .
FIG. 4 is a schematic diagram of a gas dryer 10 having a fan 56 a controller 58 , and sensors 60 . As the gas enters the inlet 12 in the direction of arrow A, the gas moves through the passageways 54 (see FIG. 3 ) in the chiller extrusion 13 , heat from the gas moves in the direction of Arrows D through the TE chips 36 into the heat exchanger 14 . Heat may also leave the gas in the chiller extrusion 13 by the second set of the TE chips 36 and move to the gas in the heating extrusion 30 as shown by arrows E. Heat leaves the heat exchanger 14 in the direction of arrows C.
In some embodiments of the invention, air flows over the heat exchanger 14 , this air flow is provided by the fan 56 . The fan 56 is an optional feature and not all embodiments may include a fan 56 .
The fan 56 may be controlled by a controller 58 . A controller 58 may be operably connected to various sensors 60 . Depending upon the data provided by the sensors 60 , the fan 56 and the TE devices 36 may be controlled by the controller 58 . The controller 58 may control the TE chips 36 , providing less or additional current to TE chips 36 . Controlling the TE chips 36 in this manner will cause more or less heat may be moved from the chiller extrusion 13 to either the heat exchanger 14 or into the re-heater 30 .
Various TE chips 36 may be controlled as a block in a first set located between the chiller extrusion 13 and heat exchanger 14 and a second set located between the chiller extrusion 13 and the re-heater 30 . In alternate embodiments of the invention, each of the TE chips 36 may be individually controlled by the controller 58 . As the gas moves through the chiller extrusion 13 it cools and moisture condenses and drops in the direction of arrow G into the separator 22 as shown in FIG. 1 and FIG. 2 .
In some embodiments of the invention, the separator 22 may be connected to a hose or a drain or to drain the condensate away from the gas dryer 10 . Arrow G schematically represents the removal of the condensate from the gas in the gas dryer 10 .
The flow of gas from the chiller extrusion 13 is turned and moved in the direction of arrow F. Gas flows into the re-heater 30 (aka the heating extension 30 ). Arrows E show heat being removed from the gas and the chiller extrusion 13 and placed into gas located in the re-heater 30 . Removing the heat generated by the second set of TE chips 36 by using the coldest air or gas temperature rather than ambient air, the performance of these chips is enhanced and a lower air or gas temperature is possible with less energy expended. Insulation 38 is located between both the re-heater 30 and chiller 13 as shown and also maybe located between the re-heater 30 and the housing 11 (housing 11 is not shown in FIG. 4 but is shown in FIG. 1 ). The gas is then exited out of the outlet 32 in the direction of arrow B.
In some embodiments of the invention, the gas entering the inlet 12 , may be about 100° F. Gas may be cooled down to about 35-40° F. as it reaches the bottom of the chiller 13 just before it enters into the separator 22 . The air or gas may be reheated back up to about 100° F. in the re-heater 30 before it exits the outlet 32 . However, these mentioned temperatures are meant to be examples only, other temperatures may also be used in accordance with the invention.
The many features and advantages of the invention are apparent from the detailed specification, and thus, it is intended by the appended claims to cover all such features and advantages of the invention which fall within the true spirit and scope of the invention. Further, since numerous modifications and variations will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation illustrated and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention. | A gas dryer includes a first opening structure forming a cooling pathway fluidly connected to the first opening; a first thermoelectric device thermally connected to the structure forming the cooling pathway and a heat exchanger. A condensate drain is located near an end of the cooling pathway and configured to drain condensate formed when a fluid is cooled along the cooling pathway. A structure forming a warming pathway is located between the condensate drain and a second opening, and a second thermoelectric device thermally connected between the structure forming cooling pathway and the structure forming the warming pathway and connected to exchange heat between the cooling pathway and the warming pathway. A method of drying a gas is provided. | 1 |
This application claims the benefit of U.S. Provisional Application No. 60/080,376, filed Apr. 1, 1998, and is a continuation of patent application Ser. No. 08/870,426, filed Jun. 6, 1997 now U.S. Pat. No. 6,097,824 and entitled “Spectral Sampling Multiband Audio Compressor,” which is a continuation of patent application Ser. No. 08/972,265, filed Nov. 18, 1997 now U.S. Pat. No. 6,072,884 and entitled “Feedback Cancellation Apparatus and Methods,” and which is a continuation of patent application Ser. No. 08/540,534, filed Oct. 10, 1995 now abandoned and entitled “Digital Signal Processing Hearing Aid” are incorporated herein by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to apparatus and methods for combining audio compression and feedback cancellation in audio systems such as hearing aids.
2. Description of the Prior Art
Mechanical and acoustic feedback limits the maximum gain that can be achieved in most hearing aids. System instability caused by feedback is sometimes audible as a continuous high-frequency tone or whistle emanating from the hearing aid. Mechanical vibrations from the receiver in a high-power hearing aid can be reduced by combining the outputs of two receivers mounted back-to-back so as to cancel the net mechanical moment; as much as 10 dB additional gain can be achieved before the onset of oscillation when this is done. But in most instruments, venting the BTE earmold or ITE shell establishes an acoustic feedback path that limits the maximum possible gain to less than 40 dB for a small vent and even less for large vents. The acoustic feedback path includes the effects of the hearing aid amplifier, receiver, and microphone as well as the vent acoustics.
The traditional procedure for increasing the stability of a hearing aid is to reduce the gain at high frequencies. Controlling feedback by modifying the system frequency response, however, means that the desired high-frequency response of the instrument must be sacrificed in order to maintain stability. Phase shifters and notch filters have also been tried, but have not proven to be very effective.
A more effective technique is feedback cancellation, in which the feedback signal is estimated and subtracted from the microphone signal. One particularly effective feedback cancellation scheme is disclosed in patent application Ser. No. 08/972,265, now U.S. Pat. No. 6,072,884 entitled “Feedback Cancellation Apparatus and Methods,” incorporated herein by reference.
Another technique often used in hearings aids is audio compression of the input signal. Both single band and multiband dynamic range compression is well known in the art of audio processing. Roughly speaking, the purpose of dynamic range compression is to make soft sounds louder without making loud sounds louder (or equivalently, to make loud sounds softer without making soft sounds softer). Therefore, one well known use of dynamic range compression is in hearing aids, where it is desirable to boost low level sounds without making loud sounds even louder.
The purpose of multiband dynamic range compression is to allow compression to be controlled separately in different frequency bands. Thus, high frequency sounds, such as speech consonants, can be made louder while loud environmental noises—rumbles, traffic noise, cocktail party babble—can be attenuated.
Patent application Ser. No. 08/540,534, entitled “Digital Signal Processing Hearing Aid,” incorporated herein by reference, gives an extended summary of multiband dynamic range compression techniques with many references to the prior art.
Patent application Ser. No. 08/870,426, entitled “Continuous Frequency Dynamic Range Audio Compressor,” incorporated herein by reference, teaches another effective multiband compression scheme.
A need remains in the art for apparatus and methods to combine audio compression and feedback cancellation in audio systems such as hearing aids.
SUMMARY OF THE INVENTION
The primary objective of the combined audio compression and feedback cancellation processing of the present invention is to eliminate “whistling” due to feedback in an unstable hearing aid amplification system, while make soft sounds louder without making loud sounds louder, in a selectable manner according to frequency.
The feedback cancellation element of the present invention uses one or more filters to model the feedback path of the system and thereby subtract the expected feedback from the audio signal before hearing aid processing occurs. The hearing aid processing includes audio compression, for example multiband compression.
As features of the present invention, the operation of the audio compression element may be responsive to information gleaned from the feedback cancellation element, the feedback cancellation may be responsive to information gleaned from the compression element, or both.
A hearing aid according to a first embodiment of the present invention comprises a microphone for converting sound into an audio signal, feedback cancellation means including means for estimating a physical feedback signal of the hearing aid, and means for modelling a signal processing feedback signal to compensate for the estimated physical feedback signal, subtracting means, connected to the output of the microphone and the output of the feedback cancellation means, for subtracting the signal processing feedback signal from the audio signal to form a compensated audio signal, a hearing aid processor including audio compression means, connected to the output of the subtracting means, for processing the compensated audio signal, and a speaker, connected to the output of the hearing aid processor, for converting the processed compensated audio signal into a sound signal.
In a second embodiment, the feedback cancellation means provides information to the compression means , and the compression means adjusts its operation in accordance with this information. For example, an increase in the magnitude of the zero coefficient vector can indicate the presence of an incoming sinusoid, which is likely due to feedback oscillations in the hearing aid. The maximum gain of the audio compression at low levels can be reduced if the feedback cancellation means detects an increase in the magnitude of the zero coefficient vector.
In a third embodiment, the compression means provides information, for example input signal power levels at various frequencies, to the feedback cancellation means, and the feedback cancellation element adjusts its operation in accordance with this information. For example, the feedback cancellation adaptation constant can be adjusted based upon the power level of one or more of the frequency bands of the audio compressor. For example, the adaptation time constant of the feedback cancellation element could be adjusted based on the output of one of the compression bands or a weighted combination of two or more bands.
In a fourth embodiment, the compression means provides information to the feedback cancellation means, and the feedback cancellation means provides information to the compression means, and each element adjusts its operation in accordance with the information obtained from the other.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 (prior art) is a flow diagram showing a hearing aid incorporating multiband audio compression.
FIG. 2 (prior art) is a block diagram showing a hearing aid incorporating feedback cancellation.
FIG. 3 is a block diagram showing a hearing aid according to the present invention, incorporating compression and feedback cancellation.
FIG. 4 is a block diagram showing a hearing aid according to the present invention, incorporating compression and feedback cancellation, wherein the compression element modifies its operation according to information from the feedback cancellation.
FIG. 5 is a block diagram showing a hearing aid according to the present invention, incorporating compression and feedback cancellation, wherein the feedback cancellation element modifies its operation according to information from the compression element.
FIG. 6 is a flow diagram showing a hearing aid according to the present invention, incorporating compression and feedback cancellation, wherein the compression element modifies its operation according to information from the feedback cancellation, and the feedback cancellation element modifies its operation according to information from the compression element.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 (prior art) is a flow diagram showing an example of a hearing aid 10 incorporating multiband audio compression 40 . This invention is described in detail in U.S. patent application Ser. No. 08/870,426, entitled “Spectral Sampling Multiband Audio Compressor.” An audio input signal 52 enters microphone 12 , which generates input signal 54 . Signal 54 is converted to a digital signal by analog to digital converter 15 , which outputs digital signal 56 . This invention could be implemented with analog elements as an alternative. Digital signal 56 is received by filter bank 16 , which is implemented as a Short Time Fourier Transform system, where the narrow bins of the Fourier Transform are grouped into overlapping sets to form the channels of the filter bank. However, a number of techniques for constructing filter banks in the frequency domain or in the time domain, including Wavelets, FIR filter banks, and IIR filter banks, could be used as the foundation for filter bank design.
Filter bank 16 filters signal 56 into a large number of heavily overlapping bands 58 . Each band 58 is fed into a power estimation block 18 , which integrates the power of the band and generates a power signal 60 . Each power signal 60 is passed to a dynamic range compression gain calculation block, which calculates a gain 62 based upon the power signal 60 according to a predetermined function.
Multipliers 22 multiply each band 58 by its respective gain 62 in order to generate scaled bands 64 . Scaled bands 64 are summed in adder 24 to generate output signal 68 . Output signal 68 may be provided to a receiver (not shown) in hearing aid 10 or may be further processed.
FIG. 2 (prior art) is a block diagram showing a hearing aid incorporating feedback cancellation. This invention is described in detail in patent application Ser. No. 08/972,265, entitled “Feedback Cancellation Apparatus and Methods. Feedback path modelling 250 includes the running adaptation of the zero filter coefficients. The series combination of the frozen pole filter 206 and the zero filter 212 gives a model transfer function G(z) determined during start-up. The coefficients of the pole model filter 206 are kept at values established during start-up and no further adaptation of these values takes place during normal hearing aid operation. Once the hearing aid processing is turned, on zero model filter 212 is allowed to continuously adapt in response to changes in the feedback path as will occur, for example, when a telephone handset is brought up to the ear.
During the running processing shown in FIG. 2, no separate probe signal is used, since it would be audible to the hearing aid wearer. The coefficients of zero filter 212 are updated adaptively while the hearing aid is in use., The output of hearing aid processing 240 is used as the probe. In order to minimize the computational requirements, the LMS adaptation algorithm is used by block 210 . The adaptation is driven by error signal e(n) which is the output of the summation 208 . The inputs to the summation 208 are the signal from the microphone 202 , and the feedback cancellation signal produced by the cascade of the delay 214 with the all-pole model filter 206 in series with the zero model filter 212 . The zero filter coefficients are updated using LMS adaptation in block 210 .
FIG. 3 is a block diagram showing a hearing aid 300 according to the present invention, incorporating compression 340 and feedback cancellation 350 . Other types of hearing aid processing, for example direction sensitivity or noise suppression, could also be incorporated into block 340 . An example of a compression scheme which could be used is shown in block 40 of FIG. 1, but the invention is by no means limited to this particular compression scheme. Many kinds of compression could be used. Similarly, an example of feedback cancellation is shown in block 250 of FIG. 2, but many other types of feedback cancellation could be used instead, including algorithms operating in the frequency domain as well as in the time domain.
Microphone 202 converts input sound 100 into an audio signal. Though this is not shown, the audio signal would generally be converted into a digital signal prior to processing. Feedback cancellation means 350 estimates a physical feedback signal of hearing aid 300 , and models a signal processing feedback signal to compensate for the estimated physical feedback signal. Subtracting means 208 , connected to the output of microphone 202 and the output of feedback cancellation means 350 , subtracts the signal processing feedback signal from the audio signal to form a compensated audio signal. Compression processor 340 is connected to the output of subtracting means 208 , for processing the compensated audio signal. Speaker 220 , connected to amplifier 218 at the output of hearing aid processor 340 , converts the processed compensated audio signal into a sound signal. If the processed compensated audio signal is a digital signal, it is converted back to analog (not shown).
FIG. 4 is a block diagram showing a hearing aid 400 which is very similar to hearing aid 300 of FIG. 3, except that compression element 440 modifies its operation according to information from feedback cancellation 450 . Depending upon the type of feedback cancellation, the types of information available and useful to compression block 440 will vary. Taking as an example a feedback cancellation block 450 identical to 250 of FIG. 2, the coefficients of zero model 212 will change with time as feedback cancellation 350 attempts to compensation for feedback.
Testing one or more of these coefficients to determine whether they are outside expected ranges in magnitude, or are changing faster than expected, gives a clue as to whether feedback cancellation 350 is having difficulty compensating for the feedback. For example, an increase in the magnitude of the zero coefficient vector might indicate the presence of an incoming sinusoid.
If it appears that feedback compensation 450 is having trouble compensating for feedback, signal 406 would indicate to compression block 440 to lower gain at low levels, either for all frequencies or for selected frequencies. Thus, if compression block 440 is identical to compression block 100 of FIG. 1, signal 406 would be used to generate a control signal for one or more gain calculation blocks 20 . For example, the gain for frequencies between 1.5 KHz and 3 KHz might be lowered temporarily, as these are often the frequencies at which hearing aids are unstable. As another example, the kneepoint between the linear amplification function of compression 440 and the compression function at higher signal levels could be moved to a higher signal level. Once the zero model coefficients begin behaving normally, the gain applied by compression 440 can be partially or completely restored to normal. As a third example, the attack and/or release times of the compression 440 could be modified in response to changes in the zero model coefficients. The compressor release time, for example, can be increased when the magnitude of the zero filter coefficient vector increases and returned to its normal value when the magnitude of the zero coefficient vector decreases, thus ensuring that the compression stays at lower gains for a longer period of time when the magnitude of the zero coefficient vector is larger than normal.
FIG. 5 is a block diagram showing a hearing aid 500 which is very similar to hearing aid 300 of FIG. 3, except that feedback cancellation element 550 modifies its operation according to information from compression element 540 . For example, the adaptation time constant of feedback cancellation 550 could be adjusted based on the output of one of the compression bands.
The adaptive filter (zero model 212 in FIG. 2) used for feedback cancellation 550 adapts more rapidly and converges to a more accurate solution when the hearing aid input signal is broadband (e.g. White noise) than when it is narrowband (e.g. A tone). Better feedback cancellation system performance can be obtained by reducing the rate of adaptation when a narrowband input signal is detected. The rate of adaptation is directly proportional to the parameter (in the LMS update equation below. The spectral analysis performed by the multiband compression can be used to determine the approximate bandwidth of the incoming signal. The rate of adaptation for the adaptive feedback cancellation filter weight updates is then decreased ((made smaller) as the estimated input signal bandwidth decreases.
As another example, the magnitude of the step size used in the LMS adaptation 210 (see FIG. 2) can be made inversely proportional to the power in one or more compression bands, for example as determined by power estimation blocks 18 (see FIG. 1 ). In this particular example,, the adaptive update of the zero filter weights becomes: b k ( n + 1 ) = b k ( n ) + 2 μ σ x 2 ( n ) e ( n ) d ( n - k ) ,
b k (n+1) is the kth zero filter coefficient at time n+1,
e(n) is the error signal provided by subtraction means 208 ,
d(n−k) is the input to the adaptive filter at time n delayed by k samples, and
σ x 2 (n) is the estimated power at time n from compression 540
In particular, the filtered hearing aid input power can be obtained from one of the frequency bands of compression 540 (from one of power estimation blocks 18 shown in FIG. 1, for example). This adaptation approach offers the advantage of reduced computational requirements, since the power estimate is already available from compression 540 , while giving much faster adaptation at lower signal levels than is possible with a system which does not use power normalization 506 . Feedback compensation 550 will also adjust faster when normalized based on compression 540 input power rather than feedback compensation 550 input power, because the latter signal has been compressed, raising the level of less intense signals and thus reducing the adaptation step size after power normalization.
Another example of adjusting feedback compensation 550 operation based upon information from compression 540 is the following. The cross correlation calculation used in LMS adapt block 210 (see FIG. 2) can overflow the accumulator if the input signal to hearing aid 500 is too high. By testing the power level of the input signal to compression 540 , it is possible to determine whether the input signal is high enough to make such an overflow likely, and freeze the filter coefficients until the high input signal level drops to normal.
The test used is whether:
gpσ x 2 ( n )<θ,
where
σ x 2 (n) is the estimated power at time n of the hearing aid input signal,
g is the gain in the filter band used to estimate power,
q is the gain in pole filter 206 , and
θ is the maximum safe power level to avoid overflow
If this test is not satisfied, the adaptive filter update is not performed for that data block. Rather, the filter coefficients are frozen at their current level until the high input signal level drops to normal.
As another example, the magnitude of the step size used in the LMS adaptation 210 (see FIG. 2) can be made dependent on the envelope fluctuations detected in one or more compression bands. A sinusoid will have very little fluctuation in its signal envelope, while noise will typically have large fluctuations. The envelope fluctuations can be estimated by detecting the peaks and valleys of the signal and taking the running difference between these two values. The adaptation step size can then be made smaller as the detected envelope fluctuations decrease.
FIG. 6 is a flow diagram showing a hearing aid 600 which is very similar to hearing aid 300 of FIG. 3, except that feedback cancellation element 650 modifies its operation according to information from compression element 640 , and compression element 640 modifies its operation according to information from feedback cancellation 650 .
An example of this is a combination of the processing described in conjunction with FIG. 4 with that described in conjunction with FIG. 5 . The power estimated by the compressor or the detected envelope fluctuations in one or more bands is used to adjust the adaptive weight update, and the magnitude of the zero filter coefficient vector is used to adjust the compression gain or the compression attack and/or release times.
While the exemplary preferred embodiments of the present invention are described herein with particularity, those skilled in the art will appreciate various changes, additions, and applications other than those specifically mentioned, which are within the spirit of this invention. In particular, the present invention has been described with reference to a hearing aid, but the invention would equally applicable to public address systems, telephones, speaker phones, or any other electroacoustical amplification system where feedback is a problem. | The present invention combines audio compression and feedback cancellation in an audio system such as a hearing aid. The feedback cancellation element of the present invention uses one or more filters to model the feedback path of the system and thereby subtract the expected feedback from the audio input signal before hearing aid processing occurs. The hearing aid processing includes audio compression, for example multiband compression. The operation of the audio compression element may be responsive to information gleaned from the feedback cancellation element, the feedback cancellation may be responsive to information gleaned from the compression element, or both. | 7 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates to computerized analysis of control processes and in particular to a program working with computerized process simulations to identify energy savings.
[0002] The manufacture of many products requires the execution of complex processes typically under automated control. Such processes, including diverse processes such as oil refining, paper manufacture, synthesis of pharmaceuticals, electrical energy generation and the like, may be defined by a set of input and output material streams and input and output energy flows into and out of the process. The process may include multiple unit operations each with corresponding material streams and energy flows.
[0003] The complexity of many commercially important processes has led to the development of sophisticated simulation tools in which the streams and flows are characterized numerically and the operations on the streams modeled mathematically so that the proper operation of the process may be verified or modified before actual construction or modification. Commercial products for such simulation include, for example, AspenPlus, a process simulation software package commercially available from AspenTech of Burlington, Mass. and a similar product line commercially available from Intelligen Inc. of Scotch Plains N.J. as well as products manufactured by Pavilion Technologies of Austin, Tex.
[0004] While complex processes may be accurately simulated, optimization of the process for particular goals, for example, energy savings and cost is not inherent in the ability to simulate the process. Even when a simulation can reveal how a cost and energy savings may change with changes in the defined streams and flows, particularly for complex processes, the ability to simulate the process alone does not necessarily indicate the type or amount of modifications necessary to optimize an arbitrary parameter. For example, an accurate simulation of a process combining two chemicals in chemical reaction may indicate how the resulting product will change with changes in the input streams of the chemicals but will not necessarily suggest, for example, the introduction of an enzyme that may improve the reaction efficiency or how to change input streams to reduce energy usage. Even trial and error changes to one stream or flow to indicate how it changes energy may not reveal the correct setting for the stream or flow for global energy reduction in the process because of the problem of local minima.
[0005] Experts in process control can often identify improvements in a process's efficiency on a case-by-case basis, but software tools to assist non-experts in process optimization or to augment the abilities of experts remain elusive because of the complexity of the problem and the case-by-case nature of the solutions.
SUMMARY OF THE INVENTION
[0006] The present inventor has recognized that although complex processes often resist optimization by comprehensive automatic procedures, they may nevertheless be improved by applying expert-known patterns of optimization that tend to be applicable to a wide range of processes. The inventor has further recognized that these patterns may be automatically identified based on information generally held in the data tables of process simulation tools. Using existing or supplemental rules on changing process variables in the data of the process simulation tool, the identified patterns may be used to guide changes in the process variables to effect significant improvements in energy usage of a process.
[0007] In one embodiment, the patterns of optimization may be divided into the categories of transformative, reflexive, integrative, or cyclic, related generally to the scope of the energy-saving pattern with respect to the process. By sequentially applying the patterns in the order of these categories, increased energy improvement may be obtained.
[0008] Specifically then, in one embodiment, the invention provides a method for reducing energy consumption in manufacturing processes comprising the steps of generating a computer simulation of the manufacturing process defining material input and output streams and energy input and output flows and providing computer readable rules associated with the computer simulation defining constraints on changes in at least one of the material input and output streams and energy input and output flows. An optimizing program is executed on electronic computer to apply a series of scripts to data of the material input and output streams to identify at least one predefined pattern of energy savings applicable to the manufacturing process. Based on the identified predefined pattern of energy savings, the computer program provides variations to at least one of the input and output streams and energy input and output flows, as constrained by the computer readable rules, to the computer simulation to provide a simulation output quantifying a change in energy usage.
[0009] It is thus one object of at least one embodiment of the invention to provide a software tool for helping identify energy efficiencies in complex processes that are resistant to purely mathematical global optimization.
[0010] The manufacturing process may include multiple stages and the scripts may be organized with respect to whether the predetermined pattern of energy savings is transformative, reflexive, integrative, or cyclic, in which transformative patterns of energy savings change proportions of mass or energy used in a stage; reflexive patterns of energy savings change reuse of mass or energy in a stage; integrative patterns of energy savings change reuse of mass or energy between different stages; and cyclic patterns of energy savings change amounts of mass or energy that have been transformed or rejuvenated.
[0011] It is thus one object of at least one embodiment of the invention to provide a methodology for identifying patterns of energy savings that may be locally applied.
[0012] The method sequentially applies, first, scripts related to transformative patterns of energy savings, second, scripts related to reflexive patterns of energy savings, third, scripts related to integrative patterns of energy savings, and fourth, scripts related to cyclic patterns of energy savings.
[0013] It is thus one object of at least one embodiment of the invention to develop an order of applying local energy-saving patterns in a way that will best approximate optimized global energy savings.
[0014] The method may provide multiple simulated outputs for different scripts to a user for selection by the user of variations in material input and output streams or energy input and output flows related to a subset of the scripts before repeating step (c) with those variations selected.
[0015] It is thus one object of at least one embodiment of the invention to accept user input for improved optimization wherein the user may provide for insight not fully captured by the data of the simulation program.
[0016] The defined material input and output streams may include material identifications and characterizations of a role of the identified materials and the scripts may identify applicable patterns of energy savings based on material identifications and characterizations of the role of the materials. For example, the role of the materials may include materials identified as components of an end product and materials identified as incidental to the end product. More specifically, for example, some materials may be identified as raw materials and some identified as solvents.
[0017] It is thus one object of at least one embodiment of the invention to provide a method of identifying patterns for energy savings by automatic or semiautomatic review of the data in a pre-existing process simulation.
[0018] It is thus one object of at least one embodiment of the invention to
[0019] At least one predefined pattern of energy savings may be selected from the group consisting of dilution reduction, catalyst introduction, heat recovery, membrane separation, and material reuse; material transformation.
[0020] It is thus one object of at least one embodiment of the invention to provide compact and easily understood patterns of energy savings that may be reviewed and accepted by the user
[0021] The method may further include the step of providing a simulation output quantifying a change in cost.
[0022] It is thus an object of at least one embodiment of the invention to constrain energy savings optimization to situations having economic reality.
[0023] These particular features and advantages may apply to only some embodiments falling within the claims and thus do not define the scope of the invention.
BRIEF DESCRIPTION OF THE FIGURES
[0024] FIG. 1 is a simplified diagram of a unit operation (possibly a portion of a multi-step process) that may be optimized by the present invention, showing input and output material streams and energy flows;
[0025] FIG. 2 is a block diagram of an electronic computer suitable for execution of an optimizing program implementing the present invention and a simulation program from the prior art;
[0026] FIG. 3 is a representation of an optimizing and simulation program held in the computer of FIG. 2 and their related data structures for implementing the present invention;
[0027] FIG. 4 is a simplified representation of the data table of FIG. 3 used to hold process variables for a the simulation program;
[0028] FIG. 5 is a data flow diagram showing application of savings-pattern scripts of the present invention on the data table of FIG. 4 to identify and propose patterns of energy savings and to modify the process variables of the data table to provide comparative energy savings data;
[0029] FIG. 6 is a hierarchical diagram showing grouping of the savings-pattern scripts of FIG. 5 into categories of transformative, reflexive, integrative, or cyclic for sequential consideration;
[0030] FIG. 7 is a diagram showing the process of FIG. 1 in the context of a larger process with an example transformative change;
[0031] FIG. 8 is a figure similar to that of FIG. 7 showing example reflexive changes;
[0032] FIG. 9 is a figure similar to FIGS. 7 and 8 showing example integrative changes;
[0033] FIG. 10 is a figure similar to FIGS. 7 -9 showing example cyclic changes; and
[0034] FIG. 11 is a simplified screen diagram showing a mechanism by which a user may select proposed optimizations from the present invention in between each group of changes per the hierarchy of FIG. 6 and the display of absolute or differential energy and dollar costs.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0035] Referring now to FIG. 1 , an example unit operation 10 of an industrial process may receive inputs 12 comprised of input materials 14 being, for example, feedstock chemicals A and B that will be consumed in the unit operation 10 and a solvent S serving as an intermediary material. The unit operation 10 may also receive input energy 16 typically in the form of heat, for example, for an endothermic reaction.
[0036] Likewise, the unit operation 10 may produce outputs 20 , comprised of output materials 22 including: by-product D, unused feedstock chemicals A and B, solvent S and the desired product C. Output energy 18 , typically in the form of waste heat, is also generated.
[0037] Referring to FIG. 2 , a process including the unit operation 10 may be simulated on a computer system 30 including a processor 32 communicating with the memory 34 , for example, via a bus structure 36 . The memory 34 may hold a simulation program 38 of the type generally known in the art (and cited above) having associated data files 40 as will be described below. The memory 34 may also hold an optimizing program 42 of the present invention together with its associated data files 44 .
[0038] The bus structure 36 of the computer system 30 may also allow the processor 32 to communicate with an interface 46 for communicating with human machine interface elements 48 including, for example, a computer monitor 50 and input device 52 providing input and output to a human operator.
[0039] It will be understood that the computer system 30 may be realized in the components of an industrial control system having, for example, interconnected components of a power supply, controller, I/O modules, and network interface cards, as modules that plug into a common high speed backplane in a rack structure. Such industrial controller are known in the art and include devices manufactured by Rockwell Automation, Inc. for example under the Logix tradename. In this case,either or both of the simulation program 38 and optimizing program 42 of the present invention together with the associated data files may be held and executed by the controller module or another specialized module.
[0040] Referring now to FIG. 3 , the data files 40 of the simulation program 38 will generally include a set of models 54 describing physical processes that may be implemented by the unit operation 10 , for example, functions describing the operation chemical reactions, thermodynamic processes, and mechanical actions in processing of the inputs 12 to manufacture the outputs 20 . The models 54 may work closely in conjunction with a stream table 56 describing the above described inputs 12 and outputs 20 together with their initial states, time rates (e.g. flow), costs, etc. The stream table 56 also inferentially describes the interaction of materials and energy in the unit operation 10 through description of streams combining other streams.
[0041] Generally, the stream table 56 will hold information entered by the user for the purpose of process simulation, the user having knowledge of the unit operation 10 . The stream table 56 will thus capture process data related to a desired operating point for the process which may or may not be optimized for a particular parameter such as energy. The data files 40 may also include a rules table 58 describing rules with respect to the possible changes in the data of the stream table 56 . For example, the rules table 58 may describe ranges of purity or temperature required of materials of the streams or the possible substitution of different materials for materials of the streams. In cases where the simulation program 38 does not explicitly provide for rules table 58 , a comments field of the stream table 56 may be used. Generally the rules of the rules table 58 will be written in a script that may be interpreted by the optimizing program 42 .
[0042] Referring still to FIG. 3 , the optimizing program 42 may communicate with the simulation program 38 by reading the rules table 58 reading and writing to the stream table 56 (either directly or through the agency of the simulation program 38 ) and invoking commands to cause simulations in various experimental scenarios using the simulation program 38 .
[0043] The data files 44 of the optimizing program 42 may include a script file 60 holding energy-saving pattern scripts 76 describing common energy-saving paradigms (as will be discussed below) and scenario file 62 recording changes in the stream table 56 for various simulations that may be run on the simulation program 38 by the optimizing program 42 .
[0044] Referring now to FIG. 4 , the stream table 56 may generally define a series of material streams 64 and energy flows 66 in different rows of the stream table 56 . Each stream or flow may be given an identifier 67 and a full description 71 . In the case of material streams 64 the description 71 may include, for example, chemical composition purity and the like. The role of stream or flow is also given a role description 72 deriving from the purpose of the material of the stream or flow in the unit operation 10 . Thus, for example, a material such as ethanol could have the role of “raw material” when used in a chemical reaction to produce a product or the role of a “solvent” when used for holding reactants that produce the product, depending on its intended use. Likewise energy, for example, electrical energy, could have a role of “electroplating” or “heating”, a distinction which will be important with respect possible substitutions of other energy sources. Other additional information 74 related to the streams may be provided including flow rate, initial temperature, price, molecular weight, viscosity, density and the like. The particular information will vary according to the simulation program 38 .
[0045] Referring now to FIG. 5 , the optimizing program 42 may sequentially execute a series of savings-pattern scripts 76 held in the script file 60 , each savings-pattern scripts 76 embodying an empirically derived paradigm for energy savings, for example, changing dilution ratios to reduce solvent costs in heat and material. Each savings-pattern script 76 , when executed, causes the optimizing program 42 to scan through the stream table 56 to identify streams and their relationships that match the paradigm of the energy savings. Thus, for example, if the script 76 relates to changing dilution ratios, the script 76 will look for streams in the stream table 56 related to solvents and their solutes.
[0046] The savings-pattern scripts 76 will generally be prepared on an ad hoc basis and will not include every possible optimization of all possible processes. Using savings-pattern scripts 76 avoids the problems of attempting to construct a global optimization process that requires consideration of every process variable.
[0047] When each savings-pattern script 76 has been scanned, only a subset 78 of scripts 76 will be identified as applicable to the unit operation 10 .
[0048] Each of the selected subset 78 of savings-pattern scripts 76 will then generate a new set of input stream data 80 that will be substituted for existing stream data 82 from the stream table 56 and applied to a simulation engine 84 , being part of the simulation program 38 , to produce new output stream values 86 . The new set of input stream data 80 and new output stream values 86 will be stored in the scenario file 62 for later consideration by the user. Thus, for example, if the savings-pattern scripts 76 relates to changing dilution values, new dilution values that may form a new set of input stream data 82 to be substituted for the existing stream data 82 will be run on the simulation program 38 , and the new output stream value provided by that simulation stored in the scenario file 62 .
[0049] The data of the scenario file 62 may be provided to an output formatter 68 that may also review the stream table 56 to collect additional data used to prepare an output table 70 displaying data from the scenario file 62 together with a column indicating changes in energy or dollars caused by application of the different savings-pattern scripts 76 and thus the relative improvements in the unit operation 10 attributable to each savings-pattern scripts 76 .
[0050] Referring now to FIG. 6 , each of the savings-pattern scripts 76 may be classified according to the scope of its changes to the unit operation 10 and the associated operations that comprise the process. A first categorization is that of transformative paradigms 90 . Generally transformative paradigms for energy savings change proportions of mass or energy used in a single given unit operation of the process. A second categorization is that of reflexive paradigms 92 . Generally, reflexive paradigms of energy savings change reuse of mass or energy in a single given unit operation 10 . A third categorization is that of integrative paradigms 94 . Integrative paradigms of energy savings change reuse of mass or energy between different unit operations 10 , being part of a larger process. Finally, a fourth categorization is that of cyclic paradigms 96 . Cyclic paradigms of energy savings change amounts of mass or energy that have been transformed or rejuvenated in some manner.
[0051] The optimizing program 42 , in applying the savings-pattern scripts 76 , applies them in this order of: (1) transformative, (2) reflexive, (3) integrative, and (4) cyclic repeating the steps of reviewing the stream table 56 to find potential energy-saving paradigms that match savings-pattern scripts 76 for that category as indicated by process block 100 and then for those applicable savings-pattern scripts 76 , simulating an alternative scenario for improved energy usage as indicated by process block 102 , and finally, allowing the user or automated program to select among proposed energy-saving paradigms as indicated by process block 104 .
[0052] Only after all of the savings-pattern scripts 76 of a single grouping (e.g. transitive, reflexive, integrative, and cyclic) have been applied, per process box 100 - 104 , are the steps repeated for the next grouping. By dividing the savings-pattern scripts 76 thusly and applying them sequentially, problems of conflicting savings-pattern scripts 76 are reduced, for example, where one paradigm undoes the benefits of other paradigms or blocks the use of superior paradigms.
[0053] Referring now to FIGS. 1 and 7 , an example of this process may be illustrated in an industrial process 110 comprised of three unit processes 10 a - 10 c including unit operation 10 a (described above) which combines chemicals A and B in order to react to produce compound C. The reaction takes place in a solvent S, and reaction of A and B to produce C is endothermic, which means that heat in the form of energy input E must be input for the reaction to occur. The reaction is not 100% efficient, so there is some residual A and B left in solution. Also, an unwanted byproduct D is produced.
[0054] The stream table 56 of the process simulation program 38 for the unit operation 10 a, as simplified, may be represented by the following Table I:
[0000]
TABLE I
Item
Input
Output
A
100
8
B
100
8
C
0
160
D
0
24
S
1000
1000
E
100
92
[0055] Using this and other data in the stream table 56 the output formatter 68 may calculate the mass and energy efficiency and overall process efficiency (OPE).
[0000]
Mass
Efficiency
:
Mass
of
C
MassofA
+
B
+
C
=
160
100
+
100
+
1000
=
13
%
Energy
Efficiency
:
Change
in
Gibbs
Free
Energy
of
C
Total
Input
Energy
Overall
Process
Efficiency
:
Mass
Efficiency
×
Energy
Efficiency
=
13
%
×
3
%
=
0.39
%
[0056] In this example, the savings-pattern scripts 76 identified two possible paths of improved energy efficiency: adding a catalyst to react products A and B and changing the dilution of the products A and B in solvent S. The script provides a simple hill climb optimization for each of these energy-saving paradigms based on the identified materials of the stream tables as described above. The hill climb is effected by trying different inputs and running the simulation to provide different outputs. The output formatter 68 then analyzes the mass balance from the stream tables to recalculate the energy efficiency. The models have estimates of the cost of implements these methods, so an automated ROI calculation can be made.
[0057] A simplified output table 70 from the output formatter 68 thus has the following form:
[0000]
TABLE II
Original
Original
Revised
Revised
Est. Energy
Item
Input
Output
Paradigm
Input
Output
Savings ROI
A
100
8
Enzyme
100
1
−5%
Catalysis
B
100
8
Enzyme
100
1
−5%
Catalysis
C
0
160
Enzyme
0
180
−5%
Catalysis
D
0
24
Enzyme
0
4
−5%
Catalysis
S
1000
1000
Dilution
800
800
300%
Reduction
E
100
92
Dilution
80
73
200%
Reduction
[0058] Referring now momentarily to FIG. 11 , the output table 70 may include voting buttons 112 allowing the user to select which particular ones (or all) of these paradigms to implement. In this case, the user would likely select the dilution reduction and not the enzyme catalysts, as the latter produces a negative return on investment (for example as may it result from a high expense of the catalyst and its relative low effectiveness). Generally, by decreasing the dilution of the materials A and B in solvent S, solvent is saved as well as the cost of heating the solvent. This is largely a rule of thumb improvement that has been embodied in a savings-pattern script 76 . In addition, the output table 70 may be associated with a display 73 indicating cumulative energy savings, cost savings or return on investment. In this respect, the present program may also be used to optimize costs that are separate from energy, for example savings in material costs which may be aggregated with energy savings costs or treated individually.
[0059] Alternatively the particular paradigms to implement may be selected automatically based on ROI.
[0060] Once the transformative savings are calculated and selected, they are assumed as a starting condition for the application of the reflexive paradigms. As noted above, reflexive savings will be those that reuse a waste stream from the unit operation 10 back into the unit operation 10 . For batch operations, this means reusing something from the prior batch into the current batch.
[0061] In this case, the savings-pattern scripts 76 may identify the possibility of membrane separation of output streams A and B for reuse and solvent reuse (where output solvent S is returned for use as input solvent S), and heat recovery from the solvent. Solvent reuse is blocked by the rules of the rules table 58 indicating a particular purity of solvent is required or information characterizing the solvent in the stream table 56 or by the user manually vetoing by the operator as indicated in the following Table III:
[0000]
TABLE III
Est.
Energy
Original
Original
Revised
Revised
Savings
Item
Input
Output
Model
Input
Output
ROI
A
100
8
Membrane
94
6
30%
Separation
B
100
8
Membrane
94
6
30%
Separation
C
0
160
No Action
0
160
NA
D
0
24
No Action
0
24
NA
S
800
800
No Action,
800
800
NA
Solvent
Contaminated.
E
80
73
Heat
10
65
200%
Recovery
from Solvent
[0062] Again, the user may select particular paradigms to proceed with. The optimizing program 42 then considers the savings-pattern scripts 76 associated with integrative savings. These savings-pattern scripts 76 may compare the waste streams with resource input requirements of other unit operations in the process. In this case, the savings-pattern scripts 76 may identify the reuse of solvent in later unit operations 10 b - c and additional energy reuse; however the latter is precluded by the earlier application of the reflexive savings. Generally, the ordering of the application of the savings-pattern scripts 76 according to FIG. 6 is believed to ensure that this blockage between the applications of different paradigms only occurs when a superior paradigm blocks and inferior paradigm from the point of view of global energy reduction.
[0063] At the conclusion of the application of the integrative paradigms, the following output table 70 may be produced per Table IV:
[0000]
TABLE IV
Est.
energy
Original
Original
Revised
Revised
savings
Item
Input
Output
Model
Input
Output
ROI
A
94
6
No Action
94
6
NA
B
94
6
No Action
94
6
NA
C
0
160
No Action
0
160
NA
D
0
24
No Action.
0
24
NA
No
other process
can utilize D
S
800
800
Reuse
800
800 now
400%
solvent
categorized
in other
as
process
product
not
waste
E
10
65
No Action.
10
65
NA
Heat already
recovered
[0064] Note that by reusing the solvent, the solvent is characterized differently thus affecting the energy savings ROI computed by the output formatter 68 .
[0065] The optimizing program 42 analyzes the stream table 56 and determined that the waste solvent could be used in another unit operation where the contamination of the solvent by D is not of a concern according to the rule table 58 , so the solvent is not wasted any longer in the unit operation 10 a, but represents a product, so it is re-categorized. At this point in the process there is no reuse for byproduct D.
[0066] The optimizing program 42 then proceeds to the final step of cyclic savings-pattern scripts 76 . In this case, two savings-pattern scripts 76 identify the ability to sell product D (thus re-characterizing it) or separate and reverse react D to create source materials A and B. The following final output table 70 is generated as Table V:
[0000]
TABLE V
Est.
Energy
Original
Original
Revised
Savings
Item
Input
Output
Model
Input
Revised Output
ROI
A
94
6
No Action
94
6
NA
B
94
6
No Action
94
6
NA
C
0
160
No Action
0
160
NA
D
0
24
Membrane
0
24: Now
−20%
Separation
categorized as
and
product
Sell
D
0
24
Membrane
0
6. Incomplete
35%
Separate
reversal. 9A
reverse
and 9B
reaction
recovered
creating
A & B
S
800
800
No Action
800
800 now
NA
categorized as
product not
waste
E
10
65
No
10
65
NA
Action.
[0067] This now completes the application of the savings-pattern scripts 76 and the output formatter 68 may again compute various energy efficiencies to compare the new Overall Process Efficiency with the beginning process.
[0000]
Mass
Efficiency
:
C
+
S
A
+
B
+
S
=
160
+
800
85
*
+
85
*
+
800
=
98.9
%
(
as
compared
to
13
%
)
[0068] The 85 represents the input now required after recovering unused material and reversing D to yield A and B.
[0000]
Energy
Efficiency
:
Change
in
Gibbs
Free
Energy
of
C
Total
Input
Energy
=
3
10
*
=
30
%
(
compared
to
3
%
)
,
[0069] This energy input reflects a steady state situation. There will be an additional loss of 80 over the entire run. This is the amount of energy required to do the first batch. It will not be recovered on the last batch. If 10 batches are planned, then allocating this loss over the 10 batches increases the average input energy to 18, reflecting a Energy Efficiency of 17% which will be used in the final OPE calculation.
[0000] Overall Process Efficiency=Mass Efficiency×Energy Efficiency=98.9%×17%=16.8% (as compared to 0.39%)
[0070] In this simplified example, the optimizing program 42 improves the efficiency of this unit operation by 16.8/0.39=43 times.
[0071] The above description begins with an arbitrary operational unit 10 and proceeds generally in a direction of evident material flow, however, such an ordering is not always implicit in a complex process or desirable for optimization. In complex processes that involve multiple interrelated process steps, additional attention may be given to the problem of identifying the sequence in which unit operations are analyzed for savings, because changing a mass or energy balance in one unit operation may have effects on linked processes.
[0072] In an additional embodiment of the invention, a sequence of optimization may be adopted by analyzing energy usage of each of the operational units 10 according to the following categories:
[0073] Direct Energy
[0074] This is the energy directly required to perform the chemical or biological transformation of the unit operation 10 . This is typically described as the change in the Gibbs Free Energy of the reaction, or in the case of biological systems, the metabolic balance. It is specific to the reaction.
[0075] Indirect Energy
[0076] This is the energy that is required to facilitate the reaction but is not directly involved in the reaction. It can be thought of as amount of energy required to transfer the direct energy to the reaction. For example, one must heat all of the solvent in an endothermic reaction in order to transfer the requisite direct energy to the reacting species. The heating of the solvent is indirect energy because it just facilitates the reaction but does not participate in the reaction.
[0077] Environmental Energy.
[0078] Associated with containment, control and regulation. It is the energy of the surroundings, for example lighting, air conditioning, etc.
[0079] In optimizing a process comprised of multiple unit operations 10 the energy flows 66 may be characterized manually or automatically (in the latter case by a script system similar to scripts 76 described above), and the OPE calculated for each unit operation 10 . The optimization may start with the unit operation 10 having the lowest energy efficiency. In the case of a tie, the unit operation 10 with the worst Mass Efficiency takes precedent. This is because mass efficiency typically provides increased savings, since it reduces both energy usage and material consumption.
[0080] Next, when performing the analysis process described above with respect to transformative, reflexive, integrative, and cyclic paradigms, these optimizations are applied with respect to energy savings in the following sequence.
[0081] Indirect Energy
[0082] Environmental Energy
[0083] Direct Energy.
[0084] Thus, the energy-saving paradigms are applied first to Indirect Energy. This is because Direct Energy processes are determined by the reaction itself, which one cannot change. Environmental Energy is analyzed after Indirect Energy because Environmental Energy is a function of Indirect Energy. For example, if one can reduce the amount of solvent, then one doesn't need as large a vessel, floor space and hence heating and air conditioning and the like.
[0085] Certain terminology is used herein for purposes of reference only, and thus is not intended to be limiting. For example, terms such as “upper”, “lower”, “above”, and “below” refer to directions in the drawings to which reference is made. Terms such as “front”, “back”, “rear”, “bottom” and “side”, describe the orientation of portions of the component within a consistent but arbitrary frame of reference which is made clear by reference to the text and the associated drawings describing the component under discussion. Such terminology may include the words specifically mentioned above, derivatives thereof, and words of similar import. Similarly, the terms “first”, “second” and other such numerical terms referring to structures do not imply a sequence or order unless clearly indicated by the context.
[0086] When introducing elements or features of the present disclosure and the exemplary embodiments, the articles “a”, “an”, “the” and “said” are intended to mean that there are one or more of such elements or features. The terms “comprising”, “including” and “having” are intended to be inclusive and mean that there may be additional elements or features other than those specifically noted. It is further to be understood that the method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order discussed or illustrated, unless specifically identified as an order of performance. It is also to be understood that additional or alternative steps may be employed.
[0087] References to “a controller” and “a processor” can be understood to include one or more controllers or processors that can communicate in a stand-alone and/or a distributed environment(s), and can thus be configured to communicate via wired or wireless communications with other processors, where such one or more processor can be configured to operate on one or more processor-controlled devices that can be similar or different devices. Furthermore, references to memory, unless otherwise specified, can include one or more processor-readable and accessible memory elements and/or components that can be internal to the processor-controlled device, external to the processor-controlled device, and can be accessed via a wired or wireless network.
[0088] The term script refers simply to a short computer program that can be executed by another computer program and is not intended to suggest or imply an interpreted language or program that coordinates different application programs.
[0089] It is specifically intended that the present invention not be limited to the embodiments and illustrations contained herein and the claims should be understood to include modified forms of those embodiments including portions of the embodiments and combinations of elements of different embodiments as come within the scope of the following claims. All of the publications described herein, including patents and non-patent publications, are hereby incorporated herein by reference in their entireties. | An energy-saving optimizing program works closely with conventional process simulation programs by applying energy saving paradigms embodied in script files that may review data inherent in the simulation program to identify possible energy-saving opportunities. When the script files identify a possible energy savings, they may interact with the simulation program to evaluate the savings potential and present the same to a user. In this way opportunistic energy savings may be provided even for processes that resist close form global optimization. | 8 |
CROSS-REFERENCE TO RELATED APPLICATION
The benefit of U.S. Provisional Patent Application Ser. No. 60/627,921, filed Nov. 15, 2004, entitled “AUTOMATED OPENING/CLOSING APPARATUS AND METHOD FOR A CONTAINER HAVING A HINGED LID,” is hereby claimed, and the specification thereof incorporated herein by this reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to the field of automated opening and closing mechanisms and, more particularly, to an automated opening/closing system for a cooking grill or similar container having a hinged lid.
2. Description of the Related Art
An outdoor cooking grill, also commonly referred to as a “barbecue grill,” “barbecue,” or simply “grill,” may include a hinged lid that covers the cooking surface. A hinged lid is a particularly common feature of grills fueled by propane and natural gas, though other grills may have lids as well. Many persons who enjoy cooking on a grill find it awkward to open the grill lid while carrying a plate of food and cooking utensils. Thus, it can be seen that needs exist for a hands-free way of opening and closing a grill with a hinged lid. It is to such an apparatus and method that the present invention is directed.
SUMMARY OF THE INVENTION
The present invention relates to an apparatus and method for automatically moving a hinged lid of a cooking grill or similar container between an opened and closed position, i.e., from a closed position to an opened position in some embodiments of the invention, from an open position to a closed position in other embodiments, or in both directions in still other embodiments. The apparatus includes an actuator system and a controller system.
The actuator system is mountable to the grill and has a means for transmitting motion to the lid, such as an arm, a system of cables and pulleys, sprockets and chains, a linear actuator, a threaded rod and ball nut, etc., or combinations thereof. The controller system has an electronic sensor, which may be of a photoelectric, optical, ultrasonic, infrared, microwave, inductive, or other suitable type, which senses the approach of a user (or object the user is carrying) to the grill and, in response, triggers the actuator system to move the lid from one position to the other, most preferably from the closed position to the open position. In some embodiments of the invention, a user-operated control, such as a foot pedal or a switch, can further be included to trigger the actuator system to move the lid in the other direction, such as from the open position back to the closed position, or alternatively, in other embodiments, as a manual override to trigger the actuator system to move the lid in the same direction as if triggered by the sensor. In still other embodiments, the controller system can close the lid in response to other conditions, such as when the sensor senses the user has left the area or after a predetermined amount of time has elapsed since the grill lid opened.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is perspective view of a grill with an attached apparatus for opening and closing the grill lid in accordance with one embodiment of the present invention.
FIG. 2 is a side elevational view of the grill and attached apparatus of FIG. 1 , shown without the foot pedal.
FIG. 3 is side elevational view similar to FIG. 2 but from the opposite side of the grill and showing the lid in an opened position.
FIG. 4 is perspective view of a grill with an attached apparatus for opening and closing the grill lid in accordance with another embodiment of the present invention.
FIG. 5 is a side elevational view of the grill and attached apparatus of FIG. 4 .
FIG. 6 is side elevational view similar to FIG. 5 but from the opposite side of the grill and showing the lid in an opened position.
FIG. 7 is schematic diagram of a circuit for controlling the opening and closing of the lid.
DETAILED DESCRIPTION
In the following description, like reference numerals indicate like components to enhance the understanding of the invention through the description of the drawings. Also, although specific features, configurations, arrangements and steps are discussed below, it should be understood that such specificity is for illustrative purposes only. A person skilled in the relevant art will recognize that other features, configurations, arrangements and steps are useful without departing from the spirit and scope of the invention.
As illustrated in FIG. 1 , an actuator system 10 is mounted to a grill 12 and electrically connected to a controller system 14 ( FIG. 7 , described below) that includes an electronic sensor 16 , such as a photoelectric eye. Grill 12 has a hinged lid 18 , shown in a closed position in FIG. 1 . As described in further detail below, controller system 14 causes actuator system 10 to move lid 18 to an open position, as shown in FIG. 3 , when electronic sensor 16 detects a person near grill 12 .
Actuator system 10 includes a suitable motor 20 (best shown in FIG. 3 ), such as a reversible 12 VDC gearmotor, with a shaft coupled to two drive pulleys 22 and 24 . Motor 20 and associated pulleys 22 and 24 are mounted to a bracket 26 , which in turn is bolted to the rear of grill 12 . Because the rear of grill 12 can be expected to become hot during use, the fastening hardware used to attach bracket 26 to grill 12 can include suitable insulating materials such as ceramic washers (not shown for purposes of clarity). A second bracket 28 can also be included to stabilize bracket 26 . Some or all of the above-described elements, such as motor 20 and associated pulleys 22 and 24 can be enclosed in a safety enclosure or shroud (not shown for purposes of clarity). The enclosure, bracket 26 , and other such elements can be made of aluminum, stainless steel or other suitable material for corrosion resistance.
One end of a first cable 30 is taken up by pulley 24 , and the other end is routed via two idler pulleys 32 and 34 to an end of an elongated stainless steel bracket 36 attached to an upper portion of the rear of lid 18 . One end of a second cable 38 is taken up by pulley 22 and routed via three idler pulleys 40 , 42 and 44 to a clevis 46 (best shown in FIG. 3 ) attached to a lower portion of the front of lid 18 . Cables 30 and 38 can comprise, for example, 1/16-inch diameter stainless steel wire rope, and the other elements can similarly be made of stainless steel for corrosion resistance, with suitable insulating washers included in the attaching hardware. Note that in other embodiments of the invention, the elements of actuator system 10 , including the motor, cables and any associated drive pulleys, idler pulleys, etc., can be arranged and mounted in any other suitable manner.
Electronic sensor 16 is mounted to grill 12 in a location suitable for detecting the approach of a person. For example, in the illustrated embodiment of the invention it is mounted beneath the shelf 48 with a small bracket (not shown for purposes of clarity). Electronic sensor 16 can be a photoelectric eye of the type known in the art as “diffuse,” which acts as a photoswitch in response to changes in light reaching it caused by a person in close proximity (e.g., approximately 24-36 inches). Electronic sensor 16 is positioned high enough to avoid activation by a family pet or small child. Although in the illustrated embodiment of the invention electronic sensor 16 is of photoelectric technology, in other embodiments it can be of any other suitable technology and can be mounted in any other suitable location. For example, a pressure mat switch can be activated when a user steps on it in front of the grill.
Controller system 14 further includes two DPDT wobblestick-type limit switches 50 and 52 . When lid 18 is in the fully closed position (see FIGS. 1-2 ), limit switch 52 is engaged by contact with lid 18 . When lid 18 is in the fully opened position (see FIG. 3 ) limit switch 50 is engaged by contact with lid 18 . In positions between these two positions, both switches 50 and 52 are disengaged.
As illustrated in FIG. 7 , controller system 14 includes, in addition to above-described electronic sensor 16 and switches 50 and 52 : a 4-pole relay 54 , a single-pole relay 56 , and two latching relays 58 and 60 . A 12 VDC battery 62 and a supplemental DC power supply 64 of the type that can be plugged into a standard electrical wall outlet (not shown) provide power to controller system 14 and motor 20 . A fuse 65 can also be included for protection. Controller system 14 can further include a manually operated override switch 66 that can be used to turn the entire system off so that lid 18 does not automatically open. In addition, controller system 14 can include a foot pedal switch 68 for causing lid 18 to close. Foot pedal switch 68 can be pneumatically activated, with an air tube (not shown) connecting a pneumatic pedal 90 on the ground to the electrical contact portion of the switch, which can be located with relays 54 - 60 and any other electronic components in a suitable enclosure (not shown) mounted in a suitable location on grill 12 .
In operation, when a user approaches grill 12 , electronic sensor 16 activates the above-described relay circuitry. In response, the circuitry powers motor 20 in a direction that reels in some of cable 30 and correspondingly reels out some of cable 38 . Cable 30 pulls on bracket 36 , causing lid 18 to open. When lid 18 reaches the fully opened position, it engages limit switch 50 , which causes the circuitry to cease powering motor 20 . Preferably, lid 18 takes no more than about three seconds to reach the fully opened position after sensor 16 is activated. Motor 20 remains in the fully opened position until the user depresses foot pedal switch 68 . In response, the circuitry powers motor 20 in the opposite direction, thereby reeling in some of cable 38 and correspondingly reeling out some of cable 30 . The action of cables 30 and 38 causes lid 18 to close. When lid 18 reaches the fully closed position, it engages limit switch 52 , which causes the circuitry to cease powering motor 20 . Although in the illustrated embodiment of the invention a foot pedal switch is used to cause lid 18 to close, in other embodiments the lid can be closed in any other suitable way, such as in response to a timer circuit. For example, the sensor can detect when the user is no longer near the grill, and the circuitry can cause the lid to close a minute or two thereafter. Additionally, the user can manually open lid 18 (e.g., if electrical power is lost) and manually close lid 18 .
An alternative embodiment of the invention is illustrated in FIGS. 4-6 . As in the embodiment described above with regard to FIGS. 1-3 , an actuator system 70 is mounted to a grill 72 and electrically connected to a controller system, which is not shown in FIGS. 4-6 for purposes of clarity but which can be the same as controller system 14 ( FIG. 7 ) described above with regard to the other embodiment, including a photoelectric eye or other electronic sensor mounted in a suitable position on grill 72 . Actuator system 70 includes a suitable motor 74 (best shown in FIG. 6 ) coupled to a drive pulley 76 . Motor 74 and pulley 76 are mounted to a bracket 78 , which in turn is bolted to the rear of grill 72 in the same manner as in the above-described embodiment. These elements can be enclosed in a heat-resistant safety enclosure or shroud (indicated in dashed line).
One end of a cable 80 is taken up by pulley 76 , and the other end is attached to the upper portion of the rear of the lid 82 . A closing arm 84 pivots on bracket 78 and has a heat-resistant roller 86 at its distal end and a tension spring 88 extending between its proximal end and bracket 78 .
In operation, when a user approaches grill 72 , the electronic sensor activates the relay circuitry of controller system 14 in the same manner as in the above-described embodiment. In response, the circuitry powers motor 74 in a direction that reels in some of cable 80 , thereby pulling lid 82 open. When lid 82 is in the fully closed position, arm 84 engages a limit switch 52 A, which is of the same type and connected in the circuitry in the same manner as limit switch 52 of the above-described embodiment. When lid 82 reaches the fully opened position (see FIG. 6 ), it engages a limit switch 50 A, which is of the same type and connected in the circuitry in the same manner as limit switch 50 of the above-described embodiment. This causes the circuitry to cease powering motor 74 . As in the above-described embodiment, motor 74 remains in the fully opened position until the user depresses the foot pedal switch (see FIG. 7 ). In the fully opened position, spring 88 biases arm 84 against the rear of lid 82 . In response to the user depressing the foot pedal switch, the circuitry powers motor 74 in the opposite direction, thereby allowing some of cable 80 to unreel from pulley 76 as arm 84 pushes lid 82 closed. When lid 82 reaches the fully closed position, it again engages limit switch 52 A, which causes the circuitry to cease powering motor 74 .
It will be apparent to those skilled in the art that various modifications and variations can be made to this invention without departing from the spirit or scope of the invention. Thus, it is intended that the present invention covers the modifications and variations of this invention provided that they come within the scope of any claims and their equivalents. With regard to the claims, no claim is intended to invoke the sixth paragraph of 35 U.S.C. Section 112 unless it includes the term “means for” followed by a participle. | An actuator moves the hinged lid of a cooking grill or similar container between a closed position and an opened position when an electronic sensor detects the approach of a person. For example, the actuator can open the lid when a person approaches, and then close the lid at a later time, such as when the person activates a switch or leaves the area, or after a time interval. | 5 |
BACKGROUND OF THE INVENTION
Trauma to the brain or spinal cord caused by physical forces acting on the skull or spinal column, by ischemic stroke, arrested breathing, cardiac arrest, Reye's syndrome, cerebral thrombosis, cerebral embolism, cerebral hemorrhage, encephalomyelitis, hydrocephalus, post-operative brain injury, cerebral infections and various concussions results in edema and swelling of the affected tissues. This is followed by ischemia, hypoxia, necrosis, temporary or permanent brain and/or spinal cord injury and may result in death. The tissue mainly affected are classified as grey matter, more specifically astroglial cells. The specific therapy currently used for the treatment of the medical problems described include various kinds of diuretics (particularly osmotic diuretics), steroids (such as, 6-α-methylprednisolone succinate) and barbiturates. The usefulness of these agents is questionable and they are associated with a variety of untoward complications and side effects. Thus, the compounds of this invention comprise a novel and specific treatment of medical problems where no specific therapy is available.
A recent publication entitled "Agents for the Treatment of Brain Injury" 1. (Aryloxy)alkanoic Acids, Cragoe et al, J. Med. Chem., (1982) 25, 567-79, reports on recent experimental testing of agents for treatment of brain injury and reviews the current status of treatment of brain injury.
The compounds of the invention have the added advantage of being devoid of the pharmacodynamic, toxic or various side effects characteristic of the diuretics, steroids and barbiturates.
DESCRIPTION OF THE INVENTION
Compounds of the instant invention are best characterized by reference to the following structural Formula (I): ##STR1## wherein: R 1 is hydrogen, lower alkyl, branched or unbranched, containing from 1 to 5 carbon atoms such as methyl, ethyl, n-propyl, isopropyl and the like, or a carboxyalkyl group containing from 2 to 6 carbon atoms such as carboxymethyl, 1-carboxyethyl, 1-carboxy-1-methylethyl, 2-carboxyethyl, 1-carboxy-1-ethylpropyl and the like;
R 4 is alkoxycarbonyl, containing from 1 to 6 carbon atoms, such as methoxycarbonyl, ethoxycarbonyl, propoxycarbonyl and the like, aminocarbonyl, alkylaminocarbonyl, containing from 2 to 7 carbon atoms, or dialkylaminocarbonyl, containing from 3 to 13 carbon atoms;
R 6 is hydrogen, lower alkyl, branched or unbranched, containing from 1 to 5 carbon atoms, cycloalkyl containing from 3 to 6 nuclear carbon atoms such as cyclopropyl, cyclobutyl, cyclopentyl and the like, or aryl such as phenyl;
X, Y are each independently hydrogen, halo or lower alkyl containing from 1 to 5 carbon atoms; and
n is 1 to 4.
Positions 4 and 6 of the cyclohexene ring, when occupied by two different groups are asymmetric, therefore the compounds of the invention exhibit optical isomerism. If there is only one asymmetric atom the product consists of a racemate composed of two enantiomers. If there are two asymmetric atoms there will be two diasteriomers, each consisting of a racemate. Diasteriomers can be separated by physical means, e.g. chromatography. Racemic compounds or their precursors can be resolved so that the pure enantiomers can be prepared, thus the invention includes each pure diasteriomer and the corresponding pure enantiomers. This is an important point since some of the racemic diasteriomers consist of one racemate which is much more active than the other one and the same is true of the two enantiomers of each racemic diasteriomer. Furthermore, the less active diasteriomer and enantiomer generally possesses the same intrinsic toxicity as the more active diasteriomer and enantiomer. In addition, it can be demonstrated that the less active diasteriomer or enantiomer depresses the inhibitory action of the active enantiomer at the tissue level. Thus, for three reasons it is advantageous to use the pure, more active diasteriomer or enantiomer rather than the mixed diasteriomer or racemate.
Since the products of the invention are acidic, the invention also includes the obvious pharmaceutically acceptable salts, such as the sodium, potassium, ammonium, trimethylammonium, piperazinium, 1-methylpiperazinium, guanidinium, bis-(2-hydroxyethyl)ammonium, N-methylglucosammonium and the like salts.
It is also to be noted that the compounds of Formula I, as well as their salts, often form solvates with the solvents in which they are prepared or from which they are recrystallized. These solvates may be used per se or they may be desolvated by heating (e.g. at 70° C.) in vacuo.
Although the invention primarily involves novel ester and amide substituted [2,3-dihydro-4-(3-oxo-1-cyclohexen-1-yl)phenoxy]alkanoic acids and their salts, it also includes their derivatives, such as oximes, hydrazones and the like. Additionally, this invention includes pharmaceutical compositions in unit dosage form containing a pharmaceutical carrier and an effective amount of a compound of Formula I, its pure diasteriomer and its pure (-) or (+) enantiomer, or the pharmaceutically acceptable salts thereof, for treating brain injury. The method of treating a person with brain injury by administering said compounds or said pharmaceutical compositions is also a part of this invention.
PREFERRED EMBODIMENT OF THE INVENTION
The preferred embbodiments of the instant invention are realized in structural Formula II: ##STR2## wherein: R 4 is alkoxycarbonyl, containing from 1 to 6 carbon atoms, such as methoxycarbonyl, ethoxycarbonyl, propoxycarbonyl and the like, aminocarbonyl, alkylaminocarbonyl, containing from 2 to 7 carbon atoms, or dialkylaminocarbonyl, containing from 3 to 13 carbon atoms;
R 6 hydrogen or lower alkyl, branched or unbranched, containing from 1 to 5 carbon atoms.
Also included are the enantiomers of each racemate.
A preferred compound is ethyl 4-[4-carboxymethoxy)-2,3-dichlorophenyl]-2-oxo-3-cyclohexene-1-carboxylate.
Also preferred is 2,3-dichloro-4-[4-(dimethylaminocarbonyl)-6ethyl-3-oxo-1-cycohexen-1-yl]phenoxy acetic acid.
Also preferred is 2,3-dichloro-4-[4-(dimethylaminocarbonyl)-3-oxo-1-cyclohexen-1-yl]phenoxy acetic acid.
Also preferred is ethyl 4-[4-(carboxymethoxy)-2,3-dichlorophenyl]-2-oxo-6-phenyl-3-cyclohexene-1-carboxylate.
Also preferred is 4-[4-(aminocarbonyl)-6-ethyl-3-oxo-1-cyclohexen-1-yl]-2,3-dichlorophenoxy-acetic acid ethanolate.
Also preferred is 4-[4-(aminocarbonyl)-3-oxo-1-cyclohexen-1-yl]-2,3-dichlorophenoxy acetic acid solvate with 2/3 acetic acid.
Especially preferred are the pure enantiomers since, in most instances, one enantiomer is more active biologically then its antipode.
Included within the scope of this invention are the pharmaceutically acceptable salts of the ester and amide substituted [2,3-dihydro-4-(3-oxo-1-cyclohexen-1-yl)phenoxy]alkanoic acids, since a major medical use of these compounds is solutions of their soluble salts which can be administered parenterally.
Thus, the acid addition salts can be prepared by the reaction of the ester and amide substituted [2,3-dihydro-4-(3-oxo-1-cyclohexen-1-yl)phenoxy]alkanoic acids of this invention with an appropriate amino, ammonium hydroxide, guanidine, alkali metal hydroxide, alkali metal carbonate, alkali metal bicarbonate, quaternary ammonium hydroxide and the like. The salts selected are derived from among the non-toxic, pharmaceutically acceptable bases.
The synthesis of the ester and amide substituted [2,3-dihydro-4-(3-oxo-1-cyclohexen-1-yl)phenoxy]alkanoic acids of formula I are generally carried out by the route illustrated below. The starting materials for compounds where R 6 =H were prepared from a compound illustrated by Formula III which is used to produce the corresponding 4-(acrylophenoxy)alkanoic acid (IIa) salt by treatment with base. This is generated and used in situ. The starting material for those compounds where R 6 =alkyl, aryl, N(R 4 ) 2 , COOR x , etc. are described in U.S. Pat. No. 3,255,241. These intermediates are illustrated by Formula II.
The compounds of the invention are prepared by the Michael reaction of a compound of the type illustrated by Formula II with a ketone of Formula IV. The ketone is converted to its carbanion by reaction with a base such as sodium methoxide, sodium ethoxide or potassium tert-butoxide. The reaction is generally conducted in a solvent such as methanol, ethanol, tert-butanol, etc., i.e. the alkanol from which the alkali metal alkoxide is derived. The molar ratio of ketone carbanion to the reactant of Formula II is in excess of 2:1 in order to allow for the neutralization of the carboxy group of the compound of Formula II. When the reaction is the compound of Formula IIa to be generated in situ from the compound of Formula III, the ratio of compound III to IV carbanion is in excess of 3:1.
After the reactants are reacted, they are generally stirred and heated at reflux for 2 to 6 hours. The product (I) is obtained upon acidification and purification. ##STR3## R 6 =H, lower alkyl R 4 =CO 2 R x , CON(R y ) 2
R x =lower alkyl
R y =H, lower alkyl
n=1-4
Those compounds possessing an asymmetric carbon atom at positions 4 or 6 of the cyclohexene ring consist of a racemate composed of two enantiomers. Compounds bearing two different substituents at positions 4- and 6- can give rise to two diasteriomers. The two diasteriomers can be separated by chromatography. The resolution of each racemate may be accomplished by forming a salt of the racemic mixture with an optically active base such as (+) or (-)amphetamine, (-)cinchonidine, dehydroabietylamine, (+) or (-)-α-methylbenzylamine, (+) or (-)(1-naphthyl)ethylamine (+) cinchonine, brucine, or strychnine and the like in a suitable solvent such as methanol, ethanol, 2-propanol, benzene, acetonitrile, nitromethane, acetone and the like. There is formed in the solution, two diastereomeric salts, one of which is usually less soluble in the solvent than the other. Repetitive recrystallization of the crystalline salt generally affords a pure diastereomeric salt from which is obtained the desired pure enantiomer. The optically pure enantiomer of the compound of Formula I is obtained by acidification of the salt with a mineral acid, isolation by filtration and recrystallization of the optically pure antipode.
The other optically pure antipode may generally be obtained by using a different optically active base to form the diastereomeric salt. It is of advantage to isolate the partially resolved acid from the filtrates of the purification of the first diastereomeric salt and to further purify this substance through the use of another optically active base. It is especially advantageous to use an optically active base for the isolation of the second enantiomer which is the antipode of the base used for the isolation of the first enantiomer. For example, if (+)-α-methylbenzylamine was used first, then (-)-α-methylbenzylamine is used for the isolation of the second (remaining) enantiomer.
The salts are prepared by reacting the acids for Formula I with an appropriate base, for example, alkali metal or alkaline earth bicarbonate, carbonate or alkoxide, an amine, ammonia, an organic quaternary ammonium hydroxide, guanidine and the like.
The reaction is generally conducted in water when alkali metal hydroxides are used, but when alkoxides and the organic bases are used, the reaction may be conducted in an organic solvent, such as ether, ethanol, dimethylformamide and the like.
The preferred salts are the pharmaceutically acceptable salts such as sodium, potassium, ammonium and the like.
Inasmuch as there are a variety of symptoms and severity of symptoms associated with grey matter edema, particularly when it is caused by head trauma, stroke, cerebral hemorrhage or embolism, post-operative brain surgery trauma, spinal cord injury, cerebral infections and various brain concussions, the precise treatment is left to the practioner. Generally, candidates for treatment will be indicated by the results of the patient's initial general neurological status, findings on specific clinical brain stem functions and findings on computerized axial tomography (CAT), nuclear magnetic resonance (NMR) or positron emission tomography (PET) scans of the brain. The sum of the neurological evaluation is presented in the Glascow Coma Score or similar scoring system. Such a scoring system is often valuable in selecting the patients who are candidates for therapy of this kind.
The compounds of this invention can be administered by a variety of established methods, including intravenously, intramuscularly, subcutaneously, or orally. The parenteral route, particularly the intravenous route of administration, is preferred, especially for the very ill and comatose patient. Another advantage of the intravenous route of administration is the speed with which therapeutic brain levels of the drug are achieved. It is of paramount importance in brain injury of the type described to initiate therapy as rapidly as possible and to maintain it through the critical time periods. For this purpose, the intravenous administration of drugs of the type of Formula I in the form of their salts is superior.
A recommended dosage range for treatment is expected to be from 0.15 mg/kg to 50 mg/kg of body weight as a single dose, preferably from 0.5 mg/kg to 20 mg/kg. An alternative to the single dose schedule is to administer a primary loading dose followed by a sustaining dose of half to equal the primary dose, every 4 to 24 hours. When this multiple dose schedule is used the dosage range may be higher than that of the single dose method. Another alternative is to administer an ascending dose sequence of an initial dose followed by a sustaining dose of 11/2 to 2 times the initial dose every 4 to 24 hours. For example, 3 intravenous doses of 8, 12 and 16 mg/kg of body weight can be given at 6 hour intervals. If necessary, 4 additional doses of 16 mg/kg of body weight can be given at 12 hour intervals. Another effective dose regimen consists of a continuous intravenous infusion of from 0.05 mg/kg/hr to 3.0 mg/kg/hr. Of course, other dosing schedules and amounts are possible.
One aspect of this invention is the treatment of persons with grey matter edema by concomitant administration of a compound of Formula I or its salts, and an antiinflammatory steroid. These steriods are of some, albeit limited, use in control of white matter edema associated with ischemic stroke and head injury. Steroid therapy is given according to established practice as a supplement to the compound of Formula I as taught elsewhere herein. Similarly, a barbiturate may be administered as a supplement to treatment with a compound of Formula I.
The compounds of Formula I are utilized by formulating them in a pharmaceutical composition such as tablet, capsule or elixir for oral administration. Sterile solutions or suspensions can be used for parenteral administration. A compound or mixture of compounds of Formula I, or its physiologically acceptable salt, is compounded with a physiologically acceptable vehicle, carrier, excipient, binder, preservative, stabilizer, flavor, etc. in a dosage form as called for by accepted pharmaceutical practice.
Illustrative of the adjuvants which may be incorporated in tablets, capsules and the like are the following: a binder such as gum tragacanth, acacia, corn starch or gelatin; an excipient such as dicalcium phosphate; a disintegrating agent such as corn starch, potato starch, alginic acid and the like; a lubricant such as magnesium stearate; a sweetening agent such as sucrose, lactose, or saccharin; a flavoring agent such as peppermint, oil of wintergreen or cherry. When the dosage unit form is a capsule, it may contain in addition to materials of the above type a liquid carrier such as a fatty oil. Various other materials may be present as coatings or to otherwise enhance the pharmaceutical elegance of the preparation. For instance, tablets may be coated with shellac, sugar or the like. A syrup or elixir may contain the active compound, sucrose as a sweetening agent, methyl and propyl parabens as preservatives, a dye and a flavoring such as cherry or orange flavor.
Sterile compositions for injection or infusion can be formulated according to conventional pharmaceutical practice by dissolving the active substance in a conventional vehicle such as water, saline or dextrose solution by forming a soluble salt in water using an appropriate base, such as a pharmaceutically acceptable alkali metal hydroxide, alkali metal bicarbonate, ammonia, amine or guanidine. Alternatively, a suspension of the active substance in a naturally occurring vegetable oil like sesame oil, coconut oil, peanut oil, cottonseed oil, etc., or a synthetic fatty vehicle like ethyl oleate or the like may be formulated for injection or infusion. Buffer, preservatives, antioxidants and the like can be incorporated as required.
The basic premise for the development of agents for the treatment of brain injury of the types described is based on the studies in experimental head injury by R. S. Bourke et. al. (R. S. Bourke, M. A. Daze and H. K. Kimelberg, Monograph of the International Glial Cell symposium, Leige, Bel. Aug. 29-31, 1977 and references cited therein) and experimental stroke by J. H. Garcia et. al. (J. H. Garcia, H. Kalimo, Y. Kamijyo and B. F. Trump, Virchows Archiv. [Zellopath.], 25, 191 (1977).
These and other studies have shown that the primary site of traumatic brain injury is in the grey matter where the process follows a pattern of insult, edema, ischemia, hypoxia, neuronal death and necrosis followed, in many instances, by irreversible coma or death. The discovery of a drug that specifically prevents the edema would obviate the sequalae.
Experimental head injury has been shown to produce a pathophysiological response primarily involving swelling of astroglial as a secondary, inhibitable process. At the molecular level, the sequence appears to be: trauma, elevation of extracellular K + and/or release of neurotransmitters, edema, hypoxia and necrosis. Astroglial swelling results directly from a K + -dependent, cation-coupled, chloride transport from the extracellular into the intracellular compartment with a concommitant movement of an osmotic equivalent of water. Thus, an agent that specifically blocks chloride transport in the astroglia is expected to block the edema caused by trauma and other insults to the brain. It is also important that such chloride transport inhibitors be free or relatively free of side effects, particularly those characteristics of many chloride transport inhibitors, such as diuretic properties. Compounds of the type illustrated by Formula I exhibit the desired effects on brain edema and are relatively free of renal effects.
That this approach is valid has been demonstrated by the correlation of the in vitro astroglial edema inhibiting effects of chloride transport inhibitors with their ability to reduce the mortality of animals receiving experimental in vivo head injury. As a final proof, one compound (ethacrynic acid) which exhibited activity both in vitro and in vivo assays was effective in reducing mortality in clinical cases of head injury. These studies are described in the Journal of Medicinal Chemistry, Volume 25, page 567 (1982), which is hereby incorporated by reference.
Three major biological assays can be used to demonstrate biological activity of the compounds. The (1) in vitro cat cerebrocortical tissue slice assay, (2) the in vitro primary rat astrocyte culture assay and (3) the in vivo cat head injury assay. The first assay, the in vitro cat cerebrocortical tissue slice assay has been described by Marshall, L. F.; Shapiro, H. M.; Smith, R. W. In "Seminars in Neurological Surgery: Neural Trauma"; Popp, A. J.; Bourke, R. S.; Nelson, L. R.; Kimelberg, H, K,. Eds.; Raven Press: New York, 1979; p. 347, by Bourke, R. S.; Kimelberg, H, K.; Daze, M. A. in Brain Res. 1978, 154, 196, and by Bourke, R. S.; Kimelberg, H. K,; Nelson, L. R. in Brain Res. 1976, 105, 309. This method constitutes a rapid and accurate method of determining the intrinsic chloride inhibitory properties of the compounds of the invention in the target issue.
The second assay method involves the in vitro primary rat astrocyte assay. The method has been described by Kimelberg, H. K.; Biddlecome, S.; Bourke, R. S. in Brain Res. 1979, 173, 111, by Kimelberg, H. K.; Bowman, C.; Biddlecome, S.; Bourke, R. S., in Brain Res. 1979, 177, 533, and by Kimelberg, H. K.; Hirata, H. in Soc. Neurosci. Abstr. 1981, 7, 698. This method is used to confirm the chloride transport inhibiting properties of the compounds in the pure target cells, the astrocytes.
The third assay method, the in vivo cat head injury assay has been described by Nelson, L. R.; Bourke, R. S.; Popp, A. J.; Cragoe, E. J. Jr.; Signorelli, A.; Foster, V. V.; Creel, in Marshall, L. F.; Shapiro, H. M.; Smith, R. W. In "Seminars in Neurological Surgery: Neural Trauma"; Popp, A. J.; Bourke, R. S.; Nelson, L. R.; Kimelberg, H. K., Eds.; Raven Press: New York, 1979; p. 297.
This assay consists of a highly relevant brain injury in cats which is achieved by the delivery of rapid repetitive acceleration-deceleration impulses to the animal's head followed by exposure of the animals to a period of hypoxia. The experimental conditions of the assay can be adjusted so that the mortality of the control animals falls in the range of about 25 to 75%. Then, the effect of the administration of compounds of this invention in reducing the mortality over that of the control animals in concurrent experiments can be demonstrated.
Using the in vitro cat cerebrocortical tissue slice assay, described in Example 1, compounds of the present invention exhibited marked activity. This test provided the principal in vitro evaluation and consisted of a determination of concentration vs. response curve. The addition of HCO 3 - to isotonic, K + -rich saline-glucose incubation media is known to specifically stimulate the transport of Cl - coupled with Na + and an osmotic equivalent of water in incubating slices of mammalian cerebral cortex. Expriments have demonstrated that the tissue locus of swelling is an expanded astroglial compartment. Thus, the addition of HCO 3 - to incubation media stimulated statistically significant and comparable increases, cerebrocortical tissue swelling and ion levels. After addition of drug to the incubation media, detailed drug concentration-response curves were then obtained. The data were expressed as percent HCO 3 - -stimulated swelling vs. drug concentraion, from which the concentration of drug providing 50% inhibition of HCO 3 - -stimulated swelling (I 50 in molarity) was interpolated. The results are expressed in Table I, below:
TABLE I______________________________________ ##STR4##Example R.sup.6 R.sup.4 Enantiomer I.sub.50 (M)______________________________________2 H CO.sub.2 C.sub.2 H.sub.5 ± 5 × 10.sup.-83 C.sub.2 H.sub.5 CON(CH.sub.3).sub.2 ± 2 × 10.sup.-74 H CON(CH.sub.3).sub.2 ± 6 × 10.sup.-75 C.sub.6 H.sub.5 CO.sub.2 C.sub.2 H.sub.5 ± 5 × 10.sup.-76 C.sub.2 H.sub.5 CONH.sub.2 ± 10.sup.-67 H CONH.sub.2 10.sup.-6______________________________________
Thus, in the in vitro assay compounds of Formula I inhibit chloride transport by 50% at concentrations as low as 5×10 -8 molar.
The following Examples are included to illustrate the in vitro cerebrocortical tissue slice assay, the preparation of representative compounds of Formula I and representative dosage forms of these compounds. It is intended that the specification and Examples be considered as exemplary only, with the true scope and spirit of the invention being indicated by the following claims.
EXAMPLE 1
In Vitro Cerebrocortical Tissue Slice Assay
Adult cats of 2-3 kg body weight were employed in tissue slice studies. Prior to sacrifice, the animals were anesthetized with ketamine hydrochloride (Ketaset), 10 mg/kg im. Eight (three control, five experimental) pial surface cerebrocortical tissue slices (0.5-mm thick; approximately 150 mg initial fresh weight) were cut successively with a calibrated Stadie-Riggs fresh tissue microtome without moistening and weighed successively on a torsion balance. During the slice preparation all operations except weighing were confined to a humid chamber. Each slice was rapidly placed in an individual Warburg flask containing 2 ml of incubation medium to room temperature. The basic composition of the incubation media, in millimoles per liter, was as follows: glucose, 10; CaCl 2 , 1.3; MgSO 4 , 1.2; KHSO 4 , 1.2; Hepes (N-2-hydroxyethylpiperazine-N'-2-ethanesulfonic acid, titrated with NaOH to pH 7.4), 20. Except when adding HCO 3 - , the osmolarity of the media was maintained isosmotic (approximately 285 mOsm/L) by reciprocal changes of Na + or K + to achieve a concentration of K + of 27 mM. The basic medium was bubbled for 30 minutes with 100% O 2 before use. When added, NaHCO 3 or triethylammonium bicarbonate (TEAB) was initially present in the sidearm of each flask at an initial concentration of 50 mM in 0.5 ml of complete medium. Nonbicarbonate control slices were incubated at 37° C. in 2.5 ml of basic medium for 60 minutes. Bicarbonate control slices were similarly incubated for an initial 20 minutes at 37° C. in 2.0 ml of basic medium to which was added from the sidearm an additional 0.5 ml of incubation medium containing 50 mM HCO 3 - , which, after mixing, resulted in a HCO 3 - concentration of 10 mM and a total volume of 2.5 ml. The incubation continues for an additional 4 minutes. The various compounds tested were dissolved by forming the sodium salts by treatment with a molar equivalent of NaHCO 3 and diluting to the appropriate concentrations. Just prior to incubation, all flasks containing HCO 3 - were gassed for 5 minutes with 2.5% CO 2 /97.5% O 2 instead of 100% O 2 .
Following the 60-minute incubation period, tissue slices were separated from incubation medium by filtration, reweighed, and homogenized in 1N HClO 4 (10% w/v) for electrolye analysis. The tissue content of ion is expressed in micromoles per gram initial preswelling fresh weight. Control slice swelling is expressed as microliters per gram initial preswelling fresh weight. The effectiveness of an inhibitor at a given concentration was measured by the amount of HCO 3 - -stimulated swelling that occurred in its presence, computed as a percent of the maximum possible. Tissue and media Na + and K + determined by emission flame photometry with Li + internal standard; Cl - was determined by amperometric titration. Tissue viability during incubation was monitored by manometry.
EXAMPLE 2
Preparation of ethyl 4-[4-(carboxymethoxy)-2,3-dichlorophenyl]-2-oxo-3-cyclohexen-1-carboxylate
Step A: [2,3-Dichloro-4-(3-dimethylaminopropionyl)phenoxy]acetic acid hydrochloride
(2,3-Dichloro-4-acetylphenoxy)acetic acid (U.S. Pat. No. 3,453,312) (7.89 g, 0.03 mole), dimethylamine hydrochoride (2.34 g, 0.03 mole), paraformaldehyde (1.05 g, 0.033 mol. equiv.) and glacial acetic (1 ml) were combined and heated on a steam bath for two hours. The reaction mixture was treated with hot ethanol (50 ml) and then cooled. The white solid was separated by filtration, washed with ethanol, dried and recrystallized from a mixture of ethanol and ether to give [2,3-dichloro-4-(3-dimethylaminopropionyl)phenoxy]acetic acid hydrochloride, m.p. 194°-196° C.
Elemental Analysis for C 13 H 15 Cl 2 NO 4 HCl Calc'd: C, 43.78; H, 4.52; N, 3.93%. Found: C, 43.91; C, 4.57; N, 3.71%.
Step B: Ethyl 4-[4-(carboxymethoxy)-2,3-dichlorophenyl]-2-oxo-3-cyclohexen-1-carboxylate
To a stirred solution of sodium methoxide (0.5 g, 0.009 moles) in ethanol (40 ml) and ethyl acetoacetate (0.9 ml, 0.0071 mole) was added [2,3-dichloro-4-(3-dimethylaminopropionyl)phenoxyacetic]acid hydrochloride (0.95 g, 0.0027 mole). The reaction mixture was heated at reflux for 21/2 hours then the solvent was distilled at reduced pressure. The residue was dissolved in water, acidified with hydrochloric acid, extracted with ether, washed with water, dried over magnesium sulfate and evaporated at reduced pressure to give 500 mg of ethyl 4-[4-(carboxymethoxy)-2,3-dichlorophenyl]-2-oxo-3-cyclohexene-1-carboxylate which melted at 193°-5° C. after purification by thin layer chromatography on silica gel (CH 2 Cl 2 :THF:methanol; 50:1:1).
Elemental Analysis for C 17 H 16 Cl 2 O 6 Calc'd: C, 52.73; H, 4.17. Found: C, 52.78; H, 4.27.
EXAMPLE 3
Preparation of 2,3-dichloro-4-[4-(dimethylaminocarbonyl)-6-ethyl-3-oxo-1-cyclohexen-1-yl]phenoxyacetic acid
N,N-Dimethylacetoacetamide (13.7 g, 0.1062M) was added at 65° to a solution of sodium (2.44 g, 0.1062M) dissolved in ethanol (200 ml). After 3-5 minutes [2,3-dichloro-4-(2-methylenebutyryl)phenoxy]acetic acid (15.2 g, 0.05M) was added and the suspension was stirred at reflux for 4 hours, cooled and concentrated. The residue was taken up in water, acidified with hydrochloric acid and extracted with chloroform. The organic extracts were washed with water and concentrated. The residue was recrystallized from acetonitrile and then from a mixture of water and acetic acid to obtain 2,3-dichloro-4-[4-(dimethylaminocarbonyl)-6-ethyl-3-oxo-1-cyclohexen-1-yl]phenoxy-acetic acid, m.p. 211° (d).
Elemental Analysis for C 19 H 21 Cl 2 NO 5 Calc'd: C, 55.08; H, 5.11; N, 3.38. Found: 55.40; H, 5.20; N, 3.11.
EXAMPLE 4
Preparation of 2,3-dichloro-4-[(4-dimethylaminocarbonyl)-3-oxo-1-cyclohexen-1yl]phenoxy acetic acid
N,N-Dimethylacetoacetamide (14.2 g, 0.11M) was added at 55° to a solution of sodium (2.53 g, 0.11M) dissolved in ethanol (150 ml). After 3-5 minutes [2,3-dichloro-4-(3-dimethylaminopropionyl)phenoxy]acetic acid hydrochloride (12.5 g, 0.035M) was added and the suspension was stirred at reflux for 3 hours, cooled, and concentrated under vacuum. The residue was taken up in water and extracted with methylene chloride. The aqueous layer was acidified with hydrochloric acid, the 2,3-dichloro-4-[(4-dimethylaminocarbonyl)-3-oxo-1-cyclohexen-1-yl]phenoxy acetic acid that separated was filtered and recrystallized from dimethyl formamide, m.p. 231° (d).
Elemental Analysis for C 17 H 17 Cl 2 NO 5 Calc'd: C, 52.86; H, 4.44; N, 3.62. Found: C, 53.07; H, 4.63; N, 3.95.
EXAMPLE 5
Preparation of ethyl 4-[4-(carboxymethoxy)-2,3-dichlorophenyl]-2-oxo-6-phenyl-3-cyclohexene-1-carboxylate
Ethyl acetoacetate (6.85 g, 0.0526M) was added at 70° to a solution of sodium (1.21 g, 0.0526M) dissolved in ethanol (150 ml). After a few minutes [2,3-dichloro-4-(3-phenyl-1-oxo-2-propenyl)phenoxy]acetic acid (8.7 g, 0.0248M) was added and the suspension was stirred at reflux for 3 hours, cooled and concentrated under vacuum. The residue was taken up in water, acidified with hydrochloric acid and extracted with methylene chloride. The organic extracts were washed with water dried over MgSO 4 and concentrated. The residue was triturated with toluene and the solid that crystallized filtered. The crude product was taken up in butyl chloride and filtered. The filtrate was concentrated under vacuum and the residue recrystallized from toluene to give ethyl 4-[4-(carboxymethoxy)-2,3-dichlorophenyl]-2-oxo-6-phenyl-3-cyclohexene-1-carboxylate, m.p. 91° C.
Elemental Analysis for C 23 H 20 Cl 2 O 6 .0.75C 7 H 8 Calc'd: C, 63.73; H, 4.92. Found: C, 63.47; H, 4.90.
EXAMPLE 6
Preparation of 4-[(4-aminocarbonyl)-6-ethyl-3-oxo-1-cyclohexen-1-yl]-2,3-dichlorophenoxy acetic acid ethanolate
Acetoacetamide (12.9 g, 0.1275M) was added at 70° to a solution of sodium (2.93 g, 0.1275M) dissolved in ethanol (150 ml). After 3 minutes [2,3-dichloro-4-(2-methylenebutyryl)phenoxy]acetic acid was added and the suspension was stirred at reflux for 3 hours, then cooled and concentrated under vacuum. The residue was taken up in water, acidified with hydrochloric acid and extracted with methylene chloride. The organic extracts were washed with water, dried over MgSO 4 and concentrated. The residue was purified by recrystallization from ethanol to obtain 4-[(4-aminocarbonyl)-6-ethyl-3-oxo-1-cyclohexen-1-yl]-2,3-dichlorophenoxy acetic acid ethanolate as an alcohol solvate, m.p. 188°-189°.
Elemental Analysis for C 17 H 17 Cl 2 NO 5 .C 2 H 5 OH Calc'd: C, 52.78; H, 5.36; N, 3.24. Found: C, 52.98; H, 4.94; N, 3.37.
EXAMPLE 7
Preparation of 4-[4-(aminocarbonyl)-3-oxo-1-cyclohexen-1-yl]-2,3-dichlorophenoxy acetic acid.2/3 acetic acid
Acetoacetamide (12.23 g, 0.121M) was added at 70° C. to a mixture of sodium (2.783 g, 0.121M) dissolved in ethanol (200 ml). After 3 minutes [2,3-dichloro-4-(3-dimethylaminopropionyl)phenoxy]acetic acid hydrochloride (15 g, 0.0388M) was added and the suspension was stirred at reflux for 3 hours then cooled and concentrated under vacuum. The residue was taken up in water, acidified with hydrochloric acid and the crude product was filtered and air dried. After recrystallization from acetic acid the pure 4-[4-(aminocarbonyl)-3-oxo-1-cyclohexen-1-yl]-2,3-dichlorophenoxy acetic acid.2/3 acetic acid was obtained as an acetic acid solvate, m.p. 216° (d).
Elemental Analysis for C 15 H 13 Cl 2 NO 5 .2/3CH 3 CO 2 H Calc'd: C, 49.26; H, 3.96; N, 3.52. Found: C, 49.40; H, 4.01; N, 3.25.
EXAMPLE 8
Preparation of ethyl 4-[4-(carboxymethoxy)-6-ethyl-2,3-dimethylphenyl]-2-oxo-3-cyclohexen-1-carboxylate
By carrying out a reaction as described in Example 2 but substituting [2,3-dimethyl-4-(2-methylenebutyryl)phenoxyacetic] (0.0035 mole) for the [2,3-dichloro-4-(3-dimethylenepropionyl)acetic acid hydrochloride (0.0027 mole) used therein, there was obtained ethyl 4-[4-(carboxymethoxy)-6-ethyl-2,3-dimethylphenyl]-2-oxo-3-cyclohexen-1-carboxylate.
EXAMPLE 9
Parenteral Solution of ethyl 4-[4-(carboxymethoxy)-2,3-dichlorophenyl]-2-oxo-3-cyclohexene-1-carboxylat
Ethyl 4-[4-(carboxymethoxy)-2,3-dichlorophenyl]-2-oxo-3-cyclohexene-1-carboxylate (500 mg) is dissolved by stirring and warming with 0.25N sodium bicarbonate solution (5.4 ml). The solution is diluted to 10 ml and sterilized by filtration. All the water that is used in the preparation is pyrogen-free. The concentration of the active agent in the final solution is 5%.
Similar parenteral solutions can be prepared by replacing the active ingredient of this Example by any of the other compounds of this invention.
______________________________________Dry-Filled Capsules Containing 100 mg of ActiveIngredient Per Capsule Per Capsule______________________________________Ethyl 4-[4-(carboxymethoxy)- 100 mg2,3-dichlorophenyl]-2-oxo-3-cyclohexene-1-carboxylateLactose 99 mgMagnesium Stearate 1 mgCapsule (Size No. 1) 200 mg______________________________________
Ethyl 4-[4-(carboxymethoxy)-2,3-dichlorophenyl]-2-oxo-3-cyclohexene-1-carboxylate is reduced to a No. 60 powder and then the lactose and magnesium stearate are passed through a No. 60 bolting cloth onto the powder and the combined ingredients admixed for 10 minutes and then filled into a No. 1 dry gelatin capsule.
Similar capsules can be prepared by replacing the active ingredient of this Example by any of the other compounds of this invention. | The invention relates to novel ester and amide substituted [2,3-dihydro-4-(3-oxo-1-cyclohexen-1-yl)phenoxy]alkanoic acids and their salts. The compounds are useful for the treatment and prevention of injury to the brain and of edema due to head trauma, stroke (particularly ischemic), arrested breathing, cardiac arrest, Reye's syndrome, cerebral thrombosis, cerebral embolism, cerebral hemorrhage, cerebral tumors, encephalomyelitis, spinal cord injury, hydrocephalus, post-operative brain injury trauma, edema due to cerebral infections and various brain concussions. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to machining by means of oscillatory vibrations and, more particularly, to ultrasonic machining for machining the front surface of a work-piece by means of a tool of which the front surface has a contour complementary to that to be reproduced on the work-piece.
The invention is applicable particularly in the field of manufacture of graphite work-pieces such as electrodes intended to be used as tools for machining by electro-erosion or again in the field of manufacture of moulds for injection moulding of synthetic-resins, ceramics or metal alloys.
2. Summary of the Prior Art
Ultrasonic machining is used more particularly for working on materials such as ceramics, calcined or vitrified materials, graphite and so on which cannot readily be machined by other methods, and has been established as particularly advantageous for reproducing complex profiles which could not be obtained by, for example, electro-erosion or by way of electro-chemical techniques because of the nature of the material to be worked.
However, the possibilities of ultrasonic machining are limited at the present time. In fact, in known machines for ultrasonic machining, the mechanical vibrations are transmitted to the tool by a vibrating part rigid with the tool whilst the work-piece is fixed. The maximum power of existing ultrasonic mechanical vibration generators does not permit the use of tools of large size. In particular, the frontal surface of the tool, which has the relief contours to be reproduced, is limited by the maximum permissible value of the section of the vibrating part. As the relief surface reproduced on the work-piece is at a maximum equal to that of the relief contour present in the front face of the tool, it is not possible to use ultrasonic machining apparatus when the work-piece has relatively large dimensions. In this case it is then necessary to resort to conventional machining methods, such as milling, which renders the operation extremely protracted and delicate, particularly when the contour to be reproduced is complex.
It has already been proposed in U.S. Pat. No. 3,465,480 to effect machining of the front face of a work-piece by means of a fixed tool, the work-piece being secured on a plate movable with an oscillatory movement by means of a mechanical transmission system including eccentrics. However, it is clear that such a system will not allow working with ultrasonic frequency with the advantages of precision and speed which it provides.
The present invention has for its object to provide an ultrasonic machining method which enables the manufacture of relatively large parts and of which use of tools which could not, because of their weight and dimensions, be put into motion to ultrasonic frequencies within reasonable times by means of existing mechanical vibration generators.
SUMMARY OF THE INVENTION
According to the present invention there is provided a method of ultrasonic machining a work-piece by means of a tool having one face with a relief contour complementary to the relief contour to be reproduced on an opposed face of the work-piece comprising the steps of mounting the work-piece on a vibratory part by means of a coupling material interposed between a face of the work-piece opposite the face to be machined and a face of the vibratory part, coupling the vibratory part to a transducer for converting electrical oscillations into mechanical vibrations, machining the said face of the work-piece on which the relief contour is to be reproduced by applying mechanical vibrations to the vibratory part and supplying abrasive material to the space between the opposed faces of the tool and the work-piece.
When it is required to produce a part of large dimensions, it is possible to machine separately several blocks or work-pieces for example of standard dimensions, so as to reproduce on at least one part of a face of each block a predetermined relief surface which is to be formed on the part as a whole, the blocks machined being then assembled so as to form the part having on one of its faces the complete profile contour required. This is made possible because, each block being secured to the vibratory part, it is possible to machine the whole of the front face of a block in conformity with the profile of the corresponding tool on condition that the block is located relatively precisely in relation to the vibratory part.
In contrast, this modular fabrication of a part cannot be effected with known machines by ultrasonic machining in which the tool is movable while the work-piece is fixed. In fact, it would then be necessary to machine the whole of the front face of each block in conformity with the profile of the face of the tool overlaying the block, which would be in practice impossible particularly because it would not be possible to provide any guide surface surrounding the surface to be machined of a block and enabling introduction of abrasive under good conditions in the space between the block and the tool. This difficulty would in particular be insurmountable when the profile to be reproduced on the block or other work-piece to be machined is at least in part concave.
The method in accordance with the present invention will be found to be particularly advantageous for the manufacture by ultrasonic machining of parts which must have, on at least one large sized portion of one of their faces, a predetermined relief contour, in particular a complex relief, parts which could not otherwise be machined except by mechanical methods, such as milling. The method in accordance with the invention is far more readily put into practice and enables a considerable time advantage, its advantages being extremely important in the economic plane.
Another advantage of the method in accordance with the invention resides in the fact that the tool, not being subject to a vibratory movement, need not be manufactured of a special material to enable transmission of the ultrasonic frequency waves. The range of materials capable of being used for tools is thus substantially enlarged.
Further according to the present invention there is provided in an ultrasonic machining installation means defining a machining enclosure, a support for a work-piece, means for imposing ultrasonic frequency vibrations on the work-piece including an electrical ultrasonic frequency vibration generator, a vibratory part coupled to this generator and a transducer for converting electrical oscillations into mechanical vibrations, means for driving the work-piece vertically, means for securing a tool on the bottom of the machining enclosure, means defining at least one passage for supplying an abrasive in a liquid vehicle, this passage delivering to the interior of the machining enclosure and being capable of supplying the abrasive/liquid mixture at a level above that of the upper face of the tool, and a recycling assembly for recycling the abrasive/liquid mixture connected to an orifice situated in the bottom of the machining enclosure.
Still further according to the present invention there is provided in an assembly for ultrasonic machining of a work-piece, a tool having a complementary relief contour to that to be reproduced in one face of the work-piece, a vibratory part, a transducer for converting electrical oscillations into mechanical vibrations, and in transmitting relationship with the vibratory part, and a coupling material connecting the face of the work-piece opposite to its first face to a face of the vibratory part opposite to its first face.
Other features and advantages of the invention will be apparent from reading the description, given hereafter by way of indicative, non-limiting example, of a particular method for putting it into practice.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagrammatic view, partly in section, of an ultrasonic machining installation for carrying out the method in accordance with the invention; and
FIG. 2 is a part manufactured by a modular ultrasonic frequency machining method in accordance with the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
A mechanical vibration generator comprises a vibratory part 1, for example of steel, of titanium or a light alloy, on an upper face 1a of which a transducer 2 is secured for converting electrical oscillations into mechanical oscillations, for example, a piezo-electric transducer. The transducer 2 is connected to a power generator 3 supplying electrical impulses at an ultrasonic frequency, for example of the order of 30 kHz.
The vibratory part 1 has an elongate parallelepiped shape and may include 1c, 1d of enlarged section. The length of the vibratory part 1 as well as the shape and the disposition of the portions 1c, 1d, are arranged to enable optimum transmission of oscillations by the vibratory part 1.
The mechanical oscillation generator thus has a construction generally similar to those used in previously proposed machines for ultrasonic machining.
The rear face 4b of a block 4 or other work-piece to be machined is connected to the lower face 1b of the vibratory part, and is, for example, of graphite, and has to be machined so as to reproduce on its front face 4a opposite to the face 4b a predetermined relief contour. Preferably, the faces 1b and 4b have the same dimensions in order to avoid creation of a discontinuity which might adversely affect the transmission of the mechanical vibrations. Moreover, in the case where the face 4b has a larger surface than that of the face 1b, cracks might appear, during the machining, in the zone of the face 4b not in contact with the face 1b.
A coupling material or means employed for effecting the coupling between the vibratory part 1 and the block 4 is selected as a function of the materials of these two elements and take into account the possible need to separate, after machining, the machined block from the vibratory part without damaging these elements.
When the final use of the machined block allows, it is not essential to separate it from the vibratory part. This is particularly the case when the machined block is intended to be used as an electrode for machining by electro-erosion, the vibratory part 1 then being capable of serving as a support for the electrode. In such a case, the connection between the block and the vibratory part may be made permanent.
However, in most cases, it is desirable to be able to separate the machined block from the vibratory part, if only to enable the re-use of the latter. Also, the coupling between the parts must be effected so as to enable separation without damage, the separation being for example, effected by application of a tensile load or by heating. The coupling material may be an adhesive or a low melting point solder may be used for this purpose.
The adhesive used may, for example, be of the thermal softening type to enable the separation to be effected between the vibratory part and the machined block by the application of tension or by heat to a relatively low temperature. This method of connection is particularly suitable when the block is of a relatively low weight. It has even been found that, for a block of small thickness of light weight, the pressure exerted continuously by the vibratory part on the block during machining is sufficient to hold it in place. Also, in this case, the provision of a connection by use of an adhesive which may be very readily broken has been found to be sufficient.
When the block is of relatively large dimensions, and in order to avoid creation at an inter-face between the vibratory part and the block of a mechanical discontinuity interrupting the propogation of vibrations, coupling will preferably be effected at least in part by brazing or soldering by means of a brazing material or solder of low fusion point, for example a brazing material of an alloy of antimony and indium. In order to effect this brazing, it is necessary in most cases to form first of all a metallic keying or primer base layer, for example a base layer of copper, on the faces to be assembled of the vibratory part and the block. This is the case in particular for a vibratory part of light alloy and a graphite work-piece. The coupling is of the type employing soldering, with metallic diffusion, at least on the atomic scale, of the metallic phase into the graphite and the material of the vibratory part.
By way of example there is described hereafter a method of forming a coupling by brazing between the vibratory part and a graphite block to be machined.
A keying base is formed on the face 1b of the vibratory part 1, when the latter is of titanium or of a light alloy, by depositing on this face, possibly pre-treated by sandblasting, a layer of iron of several tenths of a millimeter thickness for example of the order of 0.3 mm by a plasma projection process. A layer of copper of 1 to 2 mm thickness is deposited on this layer of iron by soldering on a copper element or by electroplating.
Similarly a keying base is provided by projection of a thin layer of copper, for example, of several tenths of a micron on the face 4b of the block.
The vibratory part is then brought to a temperature of 200° to 250° C, i.e. above the fusion temperature of the brazing or soldering material formed of a tin/lead alloy. The brazing or soldering material is deposited by fusion on the face 1b of the hot vibratory part in order to form a film of about 1 mm and the block is offered up, which may be at ambient temperature by causing its face 4b to rest on the film of solder. The block 4 drives out by its own weight the excess material and abuts against the face 1b of the vibratory part. If the block 4 is of low weight and small thickness, it may have a tendency to float on the film of brazing material and it is then necessary to apply to the block a force adding to its own weight. The assembly is allowed to cool to ambient temperature, excessively fast cooling being avoided because it is liable to cause cracks in the brazing material.
The blank of the part constituted by the vibratory part 1 and the block 4 is brought into its working position above the tool 5, the front face 4a of the block 4 being disposed opposite the part of the front face 5a of the tool 5 carrying the complementary relief contour of the latter for reproduction on the face 4a of the block 4.
The tool comprises a block which may be of metal or of a ceramic material or of vitrified material. The face 5a of the tool 5 particularly at its part having the complementary relief contour of the latter to be reproduced, is preferably covered with a material resistant to wear, deposited by plasma projection, atomisation or electroplating.
The tool 5 is located on the central part of the bottom of a machining enclosure 6 and is held in place by securing rods 7 screwed to the upper part of the enclosure 6, so that the securing screws lie outside of the zones in which the abrasive is likely to be projected.
The machining is effected by switching on the generator and superposing a rectilinear advancing movement to the vibratory part 1 and the block 4 towards the tool 5 on the rectilinear oscillatory movement of the vibratory part 1. The speed of advance of the block 4 towards the tool 5 may be adjusted as a function of the variations in the area of the working zone between the tool 5 and the block 4 progressively as the front face of the latter is machined. During the whole duration of the machining, abrasive is fed into the space between the tool 5 and the block 4.
This abrasive is supplied through one or more passages 8 which deliver adjacent the lateral vertical surface of the block 4. The abrasive runs along this lateral surface and, guided by the non-active edge of the front face 5a of the tool 5, enters the space between the tool 5 and the block 4. Preferably at least two passages are provided delivering to the two opposite zones of the lateral surface of the block 4 in order to supply the working zone as uniformly as possible.
When the surface of the working zone is relatively large and, particularly, when the relief contour of the tool has at least one projecting part such as 5b, 5c, resulting in a deep penetration of the block 4 into the tool 5, supplementary quantities of the abrasive may be supplied by at least one passage such as the passages 9 communicating, by orifices formed in the wall of the base of the enclosure 6, with channels 10 traversing the tool 5 and delivering to its face 5a at the level of the said projecting parts. The quantities and pressure of the abrasive material supplied by the channels 10 must however be kept within limits in order to avoid creation of a high resistance to the forces exerted on the vibratory part.
This feature enables the supply of abrasive in zones which would not readily be accessible to the abrasive supplied by the passages 9 and thereby to obtain a uniform distribution of the abrasive in the working zone. It will be noted that this feature could not readily be provided in the case where ultrasonic machining is effected by means of a movable tool, the work-piece being fixed, because the channels could not be formed in the work-piece which would be difficult taking into account the difficulties of machining and undesirable in view of the future use of the machined part. If these channels were formed in the vibratory part the tool might cause loss of power in the mechanical vibrations transmitted.
The abrasive is selected as a function of the material to be machined and consists for example of alumina, corundum, silicon carbide or boron carbide. This abrasive is used in a particle form of which the coarseness lies between, for example, 280 and 600, that is a size of several microns, these particles being carried by a liquid vehicle such as water or petroleum. The abrasive liquid mixture contains about 1 Kg of abrasive to 5 to 10 liters of liquid.
The liquid, the abrasive and the particles of material machined away are evacuated through an opening 11 situated in the base of the enclosure 6 and are collected in a recycling assembly 12.
This recycling assembly 12 comprises a decanting vessel 13 in which the particles of material machined are separated. Thus, when the latter is graphite which would, if it were recycled reduce the cutting power of the abrasive, a mass of graphite is collected on the surface of the liquid in the decantation vessel 13 and is removed therefrom. The liquid and the abrasive are then conducted into a recycling vessel 14 where they are intimately mixed by means of an agitator 15. The mixture is removed from the lower part of the recycling vessel 15, by means of a pump 16 in order to be recycled through the passages 8 and 9.
Means 17 for controlling the flow are mounted on the pipes 8 and 9. The pipes 8 and 9 may be of a plastics material and the control members 17 may be simple pinching devices controlled by a screw in order to change the effective cross-section of the passage of the pipes. The control of flow is effected as a function of the speed of advance of the block to be machined 4, of the nature of the abrasive, of the material to be machined and so on. Preferably, for a given speed of advance, the supply of liquid abrasive mixture is kept constant.
The consumption of abrasive is low and the latter is cleaned and renewed periodically after one or more machining operations.
When the duration of the machining operation is relatively long, it may be desirable to effect a periodic cleaning of the assembly of the vibrator part and the block to be machined in order to enable spraying of the face 5a of the tool 5 with a mixture of the liquid abrasive supplied through the pipes 8 and thus to renew this mixture completely in the working zone.
The ultrasonic machining is effected with maximum efficiency when the lower end of the assembly of the vibratory part and the block 4 is located at an antinode of the oscillations generated in this assembly. Because the volume of this assembly decreases during the machining operation, the useful power transmitted reduces to an extent where the frequency of the vibrations being fixed, the lower end of the assembly of the vibratory part and the block 4 becomes spaced from the location of the antinode of the vibrations.
When the block to be machined is machined to a relatively shallow depth, for example of the order of 1 to 3 mm, this loss of power is very limited, the variation in the length of the block 4 remaining negligible with respect to the wavelength of the oscillations.
When the machining must be carried out to a relatively large depth, it is desirable, in order not to affect the efficiency, to cause the frequency of the signals emitted by the generator 3 to be changed progressively with the reduction in the volume of the block to be machined. This matching of the generator 3 can be effected manually or automatically as a function of the amplitude of the advance imparted to the assembly of the vibratory part and the block 4.
At the end of the machining operation, the machined block is finally separated from the vibratory part, as indicated above. The block 4 may be machined on one part, for example, centrally, on the front fact 4a or with the aid of precise location of the block 4 and the tool 5, over the whole or a predetermined zone on the front face 4a.
The latter feature enables the manufacturer of parts of large dimensions such as the part 40 illustrated in FIG. 2. In order to carry this out the blocks 40 1 , 40 2 , and 40 12 are machined separately which, after machining, are preferably identical standard blocks of which the front surface may have an area for example of the order of 25 cm 2 . On one face of each of these blocks there is reproduced by the method such as described hereinbefore, a part of the relief contours of the front face 40a of the part 40.
Each block is machined by means of a corresponding tool, the block and the tool being located relatively to one another with precision so as to reproduce the complementary relief contour of the latter of the tool on the whole or on a predetermined zone of the front face of the block.
The machined blocks are then assembled, for example, by application of adhesive to their lateral faces, the assembly of their front machined faces constituting the desired relief contour for the whole of the part 40. | The invention relates primarily to ultrasonic machining which involves vibrating the part to be machined rather than a tool of the machine. To impart vibrations to the part to be machined it is secured to a metallic part for transmitting vibrations which is in turn connected to a transducer for converting electrical oscillations into mechanical vibrations. An abrasive is supplied to the space between the opposed operative faces of the tool and the part to be machined. The invention also relates to an installation for carrying out the method which includes a machining enclosure and a recycling assembly for recycling the abrasive liquid mixture which is used during the process. | 1 |
BACKGROUND OF THE INVENTION
The present invention relates to a skid (or sliding) road surface capable of providing a stable, low skid resistance value and a method for constructing the same.
Recently, also in driving schools, there has been an increasing necessity of providing a skid road surface in driving test roads, driving schools and the like. For example, some driving schools have a skid experiencing road to let the students acquire a careful driving technique.
Heretofore, cement concrete type and asphalt concrete type skid road surfaces have been used practically. In many of asphalt concrete type skid road surfaces, an asphalt mixture using limestone as a coarse aggregate is used to pave a road surface and the thus-paved surface is then ground for smoothing.
In using the resultant skid road surface, water is sprinkled over the road surface so as to give a uniform thickness of water layer throughout the road surface and in this wet state the skidding road surface is used for running of an automobile thereon. Thus, during vehicular running, the asphalt concrete pavement is kept soaked in water, so that the surface of the limestone exposed to the surface of the pavement is covered with the sprinkled water and the surface lime of the limestone is dissolved out with the water.
Further, the dust between the vehicular tires and the road surface causes wear of the surface limestone of the pavement.
Due to these matters, the limestone surface which was initially ground smooth becomes more and more uneven and the skid resistance increases with the lapse of time. According to the prior art, for maintaining a certain resistance value, grinding is repeated periodically or is performed upon increase of the skid resistance value, but these maintenance works require much labor and expenses.
It is the object of the present invention to eliminate the aforementioned conventional drawbacks of an asphalt concrete type skid road surface using an asphalt mixture and provide a pavement surface having a stable, low skid resistance value and not causing a secular change, as well as a method for constructing the same and an asphalt mixture suitable for the same.
SUMMARY OF THE INVENTION
As asphalt concrete type skid road surface according to the present invention employs a substantially spherical coarse aggregate as a coarse aggregate contained in an asphalt mixture which is used for constructing the said skid road surface, and the pavement surface formed according to the present invention is characterized by having a randomly continuous shape based on the upper surface shape of the coarse aggregate.
DETAILED DESCRIPTION OF THE INVENTION
The coarse aggregate used in the present invention can be considered substantially spherical in practical use and is essentially not limited if only the surface thereof is difficult to be flawed and has a hardness not causing wear and flattening during the use thereof as a skid road surface and during vehicular running thereon. For example, artificial or natural gravel is used as the coarse aggregate. Natural pebbles are particularly preferred. Characteristics which such spherical coarse aggregate should possess will now be described in more particular terms. When the tires of an automobile come into contact with the skidding road surface during running of the automobile thereon, the surface of the spherical coarse aggregate should be difficult to be flawed, have a hardness of 6% or less, preferably 3% or less, in terms of abrasion loss as measured by a Dobal tester, also should have an indoor PSV of 45 BPN or less, preferably 40 BPN or less, as measured by an aggregate accelerated abrasion test according to the BS standard which value indicates easier skidding of automobile tires during running of the automobile, further should have a difference of 4 or less between the value obtained before the aggregate accelerated abrasion test according to the BS standard and the value obtained after the same test which difference indicates the difficulty of change in skid during continuous running of an automobile on the skidding road surface, and preferably it is difficult to change according to weather conditions and has a skid resistance value of ±4 BPN (as measured using a portable skid resistance tester) after a weathering test (conducted 400 hours using a sunshine weather meter) involving repeated radiation of ultraviolet ray and sprinkling of water, with respect to a skid resistance value obtained before the same test.
Although the size of the coarse aggregate is not specially limited, the diameter thereof in the paved surfaces formed preferably corresponds to a large coarse aggregate diameter of 20 to 5 mm in the paved asphalt concrete surface course of a general road. There may be used only one kind, or two or more kinds in combination, out of those classified within the above range.
It is preferable that the coarse aggregate grains be present adjacent to each other without interruption when the asphalt mixture is used for pavement. The coarse aggregate is used in an amount of usually 50 to 90 wt %, preferably 60 to 80 wt %, based on the weight of the entire asphalt mixture.
In the asphalt mixture there also is contained a fine aggregate together with the above coarse aggregate. As the fine aggregate, sand is used at least as a main portion thereof. Both natural sand and screenings are employable if only they can be converted to asphalt mortar in the asphalt mixture. Particularly when the proportion of screenings is sand is in the range of 25 to 75 wt %, the resulting asphalt mixture is easily compacted and stable and grasps the spherical coarse aggregate well. It is necessary to keep the amount of sand within range in which the shape of the resulting pavement surface is not flat and there appear random protuberanes (partially spherical) based on the spherical coarse aggregate. Preferably, sand is used in an amount such that an average texture depth is about 1/10 to 1/20 of the maximum grain diameter of the coarse aggregate. Usually, sand is used in an amount of 15 to 30 wt %, preferably 20 to 25 wt %, based on the weight of the entire asphalt mixture. Further, stone dust is used as a filler. Preferably, stone dust is used in an amount of 1 to 8 wt %. Particularly, when a portion thereof is replaced with slaked lime, there is obtained a more outstanding effect. It is preferable that slaked lime be used in an amount of 1 to 3 wt %. As the asphalt component there is used asphalt which is commonly used for pavement. Particularly preferred is one containing an elastomer such as SBR. The elastomer content of the asphalt is preferably in the range of 1 to 10 wt %. Usually, the proportion of the asphalt component is in the range of 3 to 6 wt % of the entire mixture.
For example, the surface course of an existing road cut out and the asphalt mixture is applied for pavement to form a skid road surface. The pavement surface thus obtained is employable as a skid road surface if it assumes a shape comprising random protuberances (partially spherical) which are continuous and based on the spherical coarse aggregate. It is more desirable to remove the asphalt mortar from the pavement surface to expose the coarse aggregate surface now free of the asphalt coating.
Thus, the present invention is also concerned with a method for constructing a skid road surface characterized in that, in asphalt concrete pavement, a substantially spherical coarse aggregate is used as a coarse aggregate contained in an asphalt mixture of the surface course, and an asphalt coating on the coarse aggregate present in the pavement surface portion is removed.
It is also possible to use a coarse aggregate having a dihedral angle, as will be described later, then remove the asphalt mortar from the resulting pavement surface and at the same time grind the exposed dihedral angle portion of the coarse aggregate to round it. This mode of embodiment is also included in the present invention.
By thus removing the asphalt mortar from the resulting pavement surface, the coarse aggregate surface now free of the asphalt coating is exposed to obtain a surface shape comprising random protuberances (partially spherical) which are continuous and based on the spherical coarse aggregate.
Usually, if the thus-paved road is allowed to stand or seldom used, the asphalt mixture exhibits an increase in skid resistance with the lapse of time. This is an aging phenomenon of asphalt concrete pavement. As a result of a weathering test it turned out that this phenomenon was caused by the loss of oil component from the asphalt contained in the asphalt mortar present in the pavement surface under such weather conditions as dry-wet repetition, repetition of shining, and hot-cold repetition. On the other hand, by exposing the coarse aggregate surface as described above it is made possible to prevent the increase of skid resistance and obtain a skidding road surface superior in performance. Further, by grinding this coarse aggregate surface it is made possible to obtain a lower skid resistance and maintain it.
The method for removing the asphalt coating is not specially limited.
For example, there may be adopted a method of heating the pavement surface to soften and remove the asphalt mortar, a method of spraying a gas oil or a solvent over the pavement surface to cut back the asphalt mortar and removing the softened asphalt mortars, or a method using water jet, shot blasting or sand blasting. The method using water jet will now be described as an example. The pressure of water to be jetted is not specially limited only it permits removing of the asphalt mortar from the pavement surface. But since a distance is needed between the road surface and the discharge port, it is preferable that the said pressure be not lower than 300 kg/cm 2 . Further, the asphalt mortar removing operation can be done more efficiently by rotating plural discharge ports. Usually, the asphalt coating slightly remains on the coarse aggregate surface after removal of the asphalt mortar, but it can be removed easily with running of an automobile thereon, whereby there can be attained a low skid resistance. Where a low skid resistance value is to be obtained simultaneously with completion of the execution of work, this can be attained, for example, by dissolving an abrasive powder 4 to 10 μm in diameter in water, then applying it to the road surface after removal of the asphalt mortar and grinding the road surface with a nylon pad or the like.
In the case of shot blasting for removal of the asphalt mortar, the steel shot diameter is not specially limited if only it permits removal of the asphalt mortar from the pavement surface, but preferably it is in the range of 0.3 to 2.5 mm.
The shape thereof may be spherical or a shape having a dihedral angle provided it permits removal of the asphalt mortar. The quantity of steel shots to be used is not specially limited if only the asphalt mortar can be removed without influence of the machine moving speed upon the grinding work of the next step; for example, it is preferably in the range of 150 to 240 kg per minute at a machine moving speed of 5 to 15 m per minute.
In the case of sand blasting, the sand diameter is not specially limited if only the asphalt mortar can be removed from the pavement surface, but preferably it is in the range of 0.6 to 2 mm. The shape of sand to be used may be spherical or one having a dihedral angle provided it permits removal of the asphalt mortar. Preferably, a shape having a dihedral angle is used. The quantity of sand to be used is not specially limited if only it permits removal of the asphalt mortar, but a quantity thereof which permits efficient recovery of the sand after use is preferred, e.g. 20-30 kg/m 2 .
In the case where shot blasting is applied to an asphalt concrete pavement surface using a coarse aggregate having a hardness of 15% or less as measured in a Los Angeles abrasion loss test for evaluating the hardness of crushed stone for road, the coarse aggregate surface exposed is rough and a considerable time is required for grinding to obtain a low skid resistance. For efficient execution of the said method, for example, shot blasting is again performed using steel shots of 0.3 to 0.6 mm in diameter, or sand blasting is conducted again.
The method for grinding after removal of the asphalt mortar is not specially limited if only a low skid resistance value is obtained thereby. For example, according to a method which is often adopted, an abrasive powder 4 to 10 μm in diameter is dissolved in water, then applied to the road surface after removal of the asphalt mortar, followed by grinding using a nylon pad.
According to the present invention, the conventional drawbacks of a skid road surface constructed of asphalt concrete using an asphalt mixture can be eliminated and it becomes possible to provide a stable skidding road surface not causing a secular change of a skid resistance value under any conditions of use or weather conditions, whereby the maintenance work for maintaining the skid resistance value or properties after pavement is not required, thus permitting a great contribution to economy.
EXAMPLE
Asphalt mixtures shown in Table 1 were prepared each using asphalt, coarse aggregate, sand and stone dust (with about 30% of slaked lime incorporated therein). An existing road surface was cut out over a width of 3 m and three kinds of asphalt mixtures for skid road surface were each applied to the thus-cut road surface portion at a thickness of 4 cm in section to construct skid road surfaces of asphalt concrete.
The three kinds of the asphalt mixtures for skid road surface are of such compositions as shown in Table 1.
Table 2 shows the results of measurements made using a portable skid resistance tester after completion of the skid road surfaces. From the same table it is seen that there were obtained remarkably low skid resistance values in comparison with the value of a conventional pavement, which values little change even after the lapse of about a half year from summer to winter, thus ensuring a stable skid. Further, since the pavement furfaces obtained according to the present invention each have an uneven shape based on the coarse aggregate, a slight error in the amount of water sprinkled onto the road surface is also cancelled and thus the pavement surfaces could be used in the automobile running test without causing a hydroplaning phenomenon.
TABLE 1__________________________________________________________________________Item Kind of Mixture Mixture A Mixture B Mixture C__________________________________________________________________________Aggregate Gravel 3 57 -- --(%) Gravel 2 19 38 -- Crushed -- -- 76 stone No. 6 Crushed -- 36 -- stone No. 7 Screenings 10 11 -- Sand 10 11 19 Stone dust 4 4 5Amount of Asphalt (%) 4.3 5.1 4.5How to remove water jet water jet shot blasting +Asphalt Mortar sand blastingGrinding 1 4 μm 1 4 μm, 1 4 μm, 2 nylon pad 10 μm 10 μm 2 nylon pad 2 nylon pad__________________________________________________________________________ Note) In the item "Grinding" 1 represents the diameter of the abrasive powder used and 2 represents an abrasive material.
TABLE 2__________________________________________________________________________(Unit: BPN) Kind of Mixture A Mixture B Mixture C ExistingItem Pavement Road Surface Road Surface Road Surface Surface Course__________________________________________________________________________Skid Just after 34 41 42 61Resistance pavingValue After the 34 39 44 58 lapse of half a year__________________________________________________________________________ | A road surface specially designed to enhance skidding includes an asphalt mixture containing a plurality of substantially spherical coarse aggregates, said aggregates having a randomly continuous shape on their upper surface. A method to provide this surface involves replacing a road having an asphalt coating with the road surface of the present invention. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a signal detecting circuit for detecting a designated signal specified in a designated frequency, from an input signal to the signal detecting circuit, having a plurality of frequency components.
With respect to the above detection, there is an example of a public telephone set in a telephone system. When a calling party speaks with his called party by using a public telephone set through a central office, a metering signal is sent for accounting from the central office to the public telephone set in an accounting cycle. The metering signal is a pulse-shaped burst signal of a sine wave specified in a designated frequency such as 50 Hz, 12 kHz or 16 kHz, and the metering signal is sent to the public telephone set together with a voice signal transmitted between the calling party and the called party. Therefore, the metering signal must be detected from a signal consisting of the voice signal and the metering signal, for accounting at the public telephone set. The same kind of example can be cited from PBX in a telephone system when a subscriber of PBX speaks with his called party accommodated to a central office of the telephone system. That is, a metering signal same as mentioned above is sent to the PBX from the central office for accounting together with a voice signal transmitted between the subscriber and his called party. Therefore, in order to perform the accounting, the metering signal must be detected from a signal consisting of the voice signal and the metering signal at the PBX.
Same as the above examples, in other communication systems or signal processing system, there are many cases that a designated signal specified in a designated frequency component is required to be detected from an input signal having proper frequency components. In order to detect this kind of designated signal, a phase-lock loop circuit has been widely used in the telephone system, called PLL.
2. Description of the Prior Art
FIG. 1 shows an example of a signal detecting circuit (500) of a prior art used in a telephone system, and signals appearing in signal detecting circuit 500 in FIG. 1 are illustrated in FIGS. 2a, 2b, 2c, 2d and 2e respectively.
As well known, signal detecting circuit 500 consists of a Phase-Lock Loop circuit (PLL) 1 and a phase-lock detector 2 and outputs a detection signal S d (see FIG. 2e) when signal detecting circuit 500 receives an input signal S i (see FIG. 2a). In FIG. 2a, input signal S i is depicted in a style of a rectangle-shaped burst wave and the voice signal mentioned before is omitted, for simplicity. This rectangle-shaped burst wave is produced by limiting and waveform shaping the burst sin wave metering signal mentioned before. Means for limiting and waveform shaping the metering signal is not depicted in FIG. 1.
The PLL 1 consists of a Voltage Controlled Oscillator (VCO) 11, a Phase Comparator (PC) 12 and a Low Pass Filter (LPF) 13. The VCO 11 produces a rectangle-shaped oscillation signal S 11 specified in an oscillation frequency f 11 proportional to a DC voltage V 13 output from LPF 13. The PC 12 compares phases of input signal S i and oscillation signal S 11 every cycle of S 11 and produces a rectangle-shaped signal S 12 in a duty ratio corresponding to a phase difference (lead or lag) between phases of input signal S i and oscillation signal S 11 or to a frequency difference between frequencies of S i and S 11 . And LPF 13 outputs DC voltage V 13 to VCO 11 by performing low pass filtering to signal S 12 .
When input signal S i (metering signal) is not given to the signal detecting circuit, the duty ratio of signal S 12 is kept to 50%, DC voltage V 13 is kept to a proper value and oscillation frequency f 11 of signal S 11 is also kept to a proper frequency so-called free-running frequency (f 0 ). When input signal S i is given to the signal detecting circuit and a frequency f i of input signal S i is higher than oscillation frequency f 11 or when a phase φ i of input signal S i leads a phase φ 11 of signal S 11 , the duty ratio of signal S 12 becomes larger than 50%, resulting in increasing DC voltage V 13 and oscillation frequency f 11 . On the contrary, when frequency f i is lower than frequency f 11 or when phase φ i lags behind phase φ 11 , the duty ratio of signal S 12 becomes less than 50%, which results in decreasing DC voltage V 13 therefore lowering oscillation frequency f 11 .
When frequency f i is equal to free-running frequency f 0 , the comparison between the phases (or frequencies) of input signal S i and signal S 11 is repeated in PLL 1 until the phase-lock is established between input signal S i and signal S 11 . When the phase-lock is established, oscillation frequency f 11 becomes equal to frequency f i and the phase difference (φ i - φ 11 ) between the phases of signals S i and S 11 is kept to a fixed value of π. If free-running frequency f 0 or a frequency nearby free-running frequency f 0 is not included in input signal S i , frequency f 11 and phase φ 11 of signal S 11 cannot be locked, establishing no phase-lock.
The phase-lock detector 2 consists of an exclusive OR gate 21, an LPF 22, a voltage comparator 23 and a reference voltage source 24. The exclusive OR gate 21 performs exclusive OR operation to input signals S i and S 11 and produces output signal S 21 . The LPF 22 performs low pass filtering to signal S 21 and produces a DC voltage V 22 . The voltage comparator 23 compares DC voltage V 22 with a reference voltage V 24 from reference voltage source 24 and produces detection signal S d which is equal to the output from the signal detecting circuit 500. The detection signal S d becomes a signal representing an undetected state such as logic "0" when DC voltage V 22 is lower than reference voltage V 24 and becomes a signal representing a detected state such as logic "1" when V 22 is higher than V 24 .
In FIG. 1 and FIGS. 2a to 2e, since input signal S i is not given to signal detecting circuit 500 till t 1 (see FIG. 2a), VCO 11 oscillates in free-running frequency f 0 till t 1 as shown in FIG. 2b, so that signal S 21 becomes a rectangle-shaped signal having 50% duty cycle till t 1 as shown in FIG. 2c. In such state, DC voltage V 22 from LPF 22 is maintained lower than reference voltage V 24 , so that voltage comparator 23 outputs detection signal S d representing the undetected state (logic "0").
When input signal S i specified in frequency f i equal or nearly equal to free-running frequency f O is given to signal detecting circuit 500 in a time interval from t 1 to t 3 (see FIG. 2a), VCO 11 operates so as to bring phase φ 11 close to phase φ i by varying oscillation frequency f 11 of signal S 11 around free-running frequency f 0 , so that the phase difference (φ i - φ 11 ) approaches π (compare FIGS. 2a and 2b near t 3 ) As the phase difference approaches π, the duty ratio of output signal S 21 from exclusive OR gate 21 gradually increases (see a waveform at the time interval from t 1 to t 3 in FIG. 2c) and DC voltage V 22 from LPF 22 also rises as shown in FIG. 2d. Then, the phase-lock is established in PLL 1 and the phase difference (φ i - φ 11 ) becomes π. When the duty ratio in signal S 21 reaches 100%, DC voltage V 22 becomes reference voltage V 24 at t 2 as shown in FIG. 2d and voltage comparator 23 outputs detection signal S d representing the detected state (logic "1") as shown in FIG. 2e.
Thus, the free-running state of PLL 1 till t 1 is changed to a phase-lock state at t 2 . In other words, the time interval from t 1 to t 2 is a transition time for changing the state of PLL 1 from free-running to phase lock. When input signal S i is ended at t 3 , PLL 1 starts to bring back the state from phase-lock to free-running by a process opposite to the above, passing through the similar transition time to the above, which is not depicted in FIGS. 2a to 2d.
PROBLEMS IN THE PRIOR ART
However, in the signal detection circuit of the related art, a long transition time is required in PLL 1 to change the free-running state to the phase-lock state and vice versa as shown in FIGS. 2b and 2c, which has been a problem in the prior art. In particular, this problem becomes more remarkable in the telephone system when the metering frequency, which is equal to frequency f i of input signal S i , is as low as 50 Hz. Because, in some telephone system, such low metering frequency as 50 Hz must be employed in accordance with rules of the telephone system and a time to get the phase-lock is required to be as short as 120 millisecond. From a viewpoint of the reliability of operation, it has been hard to employ such low frequency for the metering frequency as far as the prior art is applied to the telephone system.
SUMMARY OF THE INVENTION
Therefore, an object of the present invention is to shorten a time for detecting a designated signal specified in a designated frequency from a signal having a plurality frequency components, in a signal detecting circuit including a phase-lock loop circuit (PLL).
Another object of the present invention is to increase detecting efficiency of the signal detecting circuit.
Still another object of the present invention is to increase detecting reliability of the signal detection circuit.
The above objects are achieved by providing a frequency multiplier for multiplying the designated frequency, on the passing way of the designated signal given to PLL. The frequency multiplier multiplies the designated frequency by a frequency multiplication factor. Therefore, when the designated signal is given to PLL through the frequency multiplier, the designated frequency is multiplied by the frequency multiplying factor.
As well known, PLL includes an oscillator for producing an oscillation signal specified in a free-running frequency previously determined to be equal to a frequency of a signal to be detected at PLL. When no signal to be detected is given to PLL, the oscillator performs a free-running oscillation, producing the oscillation signal specified in the free-running frequency, so that the signal detecting circuit produces an output representing that a signal to be detected is not detected by the signal detecting circuit. When a signal to be detected is given to PLL with the same frequency as the free-running frequency, phases of the signal to be detected and the oscillation signal are compared and the phase of the oscillation signal is varied until both phases are coincided to each other. When the phases are coincided to each other, which is called "phase-lock", the signal detecting circuit outputs a signal representing that the signal to be detected is detected by the signal detecting circuit.
In the process of achieving the phase-lock, it takes a time (transit time) to change the state of PLL from free-running to phase-lock after the signal to be detected is given to PLL, and similarly to the above, it takes another transit time to change the state of PLL from phase-lock to free-running after the signal to be detected disappears. However, precisely considering the transit time, there is a fact that the transit time is inversely proportional to the frequency of the signal to be detected or the free-running frequency. This is a point of the present invention. That is, in the present invention, because of increasing the frequency of the input designated signal by multiplying the frequency at the frequency multiplier, the transit time can be shortened when the free-running frequency in PLL is also increased same as the multiplied frequency of the input designated signal. As a result of shortening the transit time thus, the time for detecting the designated signal can be shortened, so that the detecting efficiency and reliability of the signal detecting circuit can be increased.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram of a signal detecting circuit of the prior art;
FIG. 2a is a waveform illustrated for an input signal to a signal detecting circuit;
FIG. 2b is a waveform illustrated for an output from a voltage controlled oscillator (VCO) in a phase-lock loop circuit (PLL) of the prior art signal detecting circuit;
FIG. 2c is a waveform illustrated for an output signal from an exclusive OR gate in a phase-lock detector of the prior art signal detecting circuit;
FIG. 2d is a DC voltage illustrated for an output signal from a low pass filter in the phase-lock detector;
FIG. 2e is an illustration of an output signal from a voltage comparator in the phase-lock detector;
FIG. 3 is a block diagram for illustrating a principle of a signal detecting circuit embodying the present invention;
FIG. 4 is a block diagram of a signal detecting circuit embodying the present invention;
FIG. 5a is a waveform illustrated for an input signal to a frequency multiplier in the signal detecting circuit;
FIG. 5b is a waveform illustrated for an output signal from a diode bridge in the frequency multiplier;
FIG. 5c is a waveform illustrated for an output signal from a low pass filter in the frequency multiplier;
FIG. 5d is a waveform illustrated for an output signal from a waveform shaper in the frequency multiplier;
FIG. 5e is a waveform illustrated for an output signal from a voltage controlled oscillator in a phase-lock loop circuit of the signal detecting circuit;
FIG. 5f is a waveform illustrated for an output signal from an exclusive OR gate in a phase-lock detector of the signal detecting circuit;
FIG. 5g is an illustration of an output signal from an low pass filter in the phase-lock detector; and
FIG. 5h is an illustration of an output signal from a voltage comparator in the phase-lock detector.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 3 illustrates a principle of a signal detecting circuit 600 embodying the present invention. In FIG. 3, signal detecting circuit 600 consists of a frequency multiplier 100, a PLL 200 and a phase-lock detector 300. The frequency multiplier 100 is a circuit newly provided in signal detecting circuit 600 for the present invention and PLL 200 and phase-lock detector 300 are functionally same as PLL 1 and phase-lock detector 2 in signal detecting circuit 500 of the prior art respectively. The frequency multiplier 100 multiplies a frequency f i of input signal S i to signal detecting circuit 600 by a multiplying factor N, producing output signal S 100 . The PLL 200 performs phase-lock so that a free-running oscillation signal in PLL 200 is locked in a designated signal specified in a designated frequency in signal S 100 received from frequency multiplier 100, producing an output signal S 200 . The phase-lock detector 300 compares signal S 100 with signal S 200 for detecting whether these signals are in a phase-lock state with each other and produces detection signal S d . The detection signal S d becomes the signal representing the detected state if there is a signal specified in a frequency being one Nth of multiplied frequency in input signal S i .
Since the multiplied frequency is used, phase-lock becomes possible in PLL 200 even though the time interval of the pulse-shaped input signal S i is short, which greatly increases the detecting ability of the metering signal and therefore increases a processing speed of the telephone system.
A preferred embodiment of the present invention will be explained in reference to FIG. 4 and FIGS. 5a to 5h below. FIG. 4 shows a schematic diagram of signal detecting circuit 600 embodying the present invention and FIGS. 5a to 5h illustrate the waveforms of signals appearing in the schematic diagram shown in FIG. 4. In FIG. 4 and 5a to 5h, the same reference numeral or symbol as in FIGS. 1 and 2a to 2e designates the same part, circuit or signal as in FIGS. 1 and 2a to 2e.
The signal detecting circuit 600 consists of a frequency multiplier 3, a PLL 4 and a phase-lock detector 5 as shown in FIG. 4. In FIG. 4, frequency multiplier 3, PLL 4 and phase-lock detector 5 are provided as frequency multiplier 100, PLL 200 and phase-lock detector 300 in FIG. 3 respectively. The frequency multiplier 3 is provided so as to operate under a condition that N = 2 in this embodiment, so that frequency multiplier 3 consists of a diode bridge 31 including four diodes D 1 , D 2 , D 3 and D 4 and additional circuits such as: an LPF 32 consisting of an operational amplifier A 1 , resistors R 2 , R 3 , R 4 and R 5 and capacitors C 1 and C 2 ; and a waveform shaper 33. The diode bridge 31 produces an output signal S 31 specified in a doubled frequency of frequency f i of input signal S i by performing fullwave rectification to input signal S i . The LPF 32 produces an output signal S 32 by extracting a base frequency component being a doubled frequency component of input signal frequency f i . The waveform shaper 33 produces output signal S 33 formed to a pulse-shaped wave by shaping signal S 32 . Therefore, waveform shaper 33 produces output signal S 33 formed to a rectangle-shaped wave specified in a doubled frequency of frequency f i of input signal S i .
The PLL 4 consists of VCO 41, PC 42 and LPF 43 each having the same function as VCO 11, PC 12 and LPF 13 in PLL 1 in FIG. 1 respectively. That is, the VCO 11 has a free-running frequency f 40 equal or nearly equal to a doubled frequency f 33 of a designated signal (metering signal) included in input signal S i . As a result, when signal S 33 from frequency multiplier 3 includes a signal specified in the doubled frequency f 33 , PLL 4 performs the phase-lock between the doubled frequency f 33 and a oscillation frequency of VCO 41 and produces output signal S 41 having a phase different from a phase of the designated signal as much as π. A phase lock detector 5 in FIG. 4 consists of an exclusive OR gate 51, an LPF 52, voltage comparator 53 and a reference voltage source 54 and detects that PLL 4 is in the phase-lock state with the designated signal in signal S 33 , same as phase lock detector 2 in FIG. 1.
The above operation of signal detecting circuit 600 will be further explained in reference to FIGS. 5a to 5h. FIG. 5a shows a waveform of input signal S i . However, in FIG. 5a, only a designated signal such as a metering signal is depicted in a style of burst signal appearing in a time interval between t 11 and t 13 , omitting other signals such as a voice signal for simplicity. When the designated signal is given to diode bridge circuit 31 as shown in FIG. 5a, diode bridge circuit 31 performs full-wave rectification, producing signal S 31 as shown in FIG. 5b. The LPF 32 extracts a doubled frequency component of the designated signal so as to produce signal S 32 as shown in FIG. 5c. Then waveform shaper 33 shapes signal S 32 so as to produce signal S 33 having a square-shaped wave as shown in FIG. 5d. Since no signal is given to PLL 4 till t 11 as shown in FIG. 5d, VCO 41 oscillates signal S 41 specified in a free-running frequency f 0 in 50% duty ratio till t as shown in FIG. 5e. In such state, exclusive OR gate 51 outputs signal S 51 in 50% duty ratio till t 11 as shown in FIG. 5f, and output voltage V 52 from LPF 52 is maintained at a voltage lower than reference voltage V 54 as shown in FIG. 5g, so that voltage comparator 53 produces detection signal S d representing an undetected state (logic "0") as shown in FIG. 5d.
When t 11 passes, the phase of the signal S 41 specified in the free-running frequency f 0 varies so as to lock to the phase of signal S 33 in PLL 4, taking a transit time (from t 11 to t 12 ) as seen from comparison between FIGS. 5e and 5f in an interval from t 11 to t 12 . That is, during the transit time, PLL 4 compares phase φ 33 of signal S 33 with phase φ 41 of signal S 41 and varies the phase φ 33 so that the phase difference (φ 33 - φ 41 ) becomes π by making phase φ 33 follow phase φ 41 .
In phase lock detector 5, as the phase difference (φ 33 - φ 41 ) closes to π, the duty ratio of signal S 51 from exclusive OR gate 51 increases gradually and therefore output voltage V 52 from LPF 52 increases. When the phase difference becomes π, the duty ratio of signal S 51 reaches 100% as shown in FIG. 5f and output voltage V 52 exceeds reference voltage V 54 at t 12 as shown in FIG. 5g, so that voltage comparator 53 produces detection signal S d presenting the detected state (logic "1") and the detected state continues as far as V 52 exceeds reference voltage V 52 as shown in FIG. 5h.
When the burst input signal S i is over at t 13 , PLL 4 is brought back to the free-running state at t 14 in a opposite process to the above phase-lock process through a transition time from t 13 to t 14 as shown after t 13 in FIGS. 5f, 5g and 5h.
As seen from the above explanation of the embodiment, since frequency multiplier 3 doubles the frequency f i of input signal S i and the phase-lock is performed by using the oscillation signal specified in the doubled frequency in PLL 4, the transit time (from t 11 to t 12 ) for establishing the phase-lock state on PLL 4 and the transit time (from t 13 to t 14 ) for bringing PLL 4 back to the free-running state can be shortened to as little as one half of that in the prior art. As a result, the signal detection can be performed, leaving a sufficient margin though the signal to be detected is given to the signal detecting circuit 600 in a short time.
In the above explanation of the embodiment, the detection of the metering signal in the telephone system has been discussed. However, the present invention is not limited to apply the telephone system. The present invention can be applied to other communication system or signal processing systems. The block diagram shown in FIG. 4 is an embodiment of the present invention. Other circuits can be considered to achieve the object of the present invention. In the explanation of the embodiment in reference to FIG. 4 and FIGS. 5a to 5h, the multiplying factor N is set to two in frequency multiplier 3, however, another number larger than two is applicable to N. The constitution of frequency multiplier 100, PLL 200 and phase lock detector 300 in FIG. 3 is concretely shown in frequency multiplier 3, PLL 4 and phase lock detector 5 in FIG. 4 respectively, however, the constitution in FIG. 3 is not limited to that in FIG. 4. | A designated burst signal specified in a designated frequency is detected from an all-inclusive signal specified in a plurality of frequencies, by multiplying a frequency of the all-inclusive signal by a multiplying factor so as to produce a multiplied output signal, performing a phase-lock loop operation between the multiplied output signal and an oscillated signal produced for performing the phase-lock loop operation and specified in a multiplied frequency of the designated frequency by the multiplying factor, so as to produce a phase-lock output signal and comparing the multiplied output signal and the phase-lock output signal for producing a detected output signal representing whether the designated burst signal is in the all-inclusive signal. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This is a continuation of co-pending application Ser. No. 12/372,862, filed Feb. 18, 2009.
FIELD OF THE INVENTION
This invention relates, in general, to equipment utilized and operations performed in conjunction with a subterranean well and, in particular, to an apparatus and method for controlling the connection and disconnection speed of downhole connectors.
BACKGROUND OF THE INVENTION
Without limiting the scope of the present invention, its background is described with reference to using optical fibers for communication and sensing in a subterranean wellbore environment, as an example.
It is well known in the subterranean well completion and production arts that downhole sensors can be used to monitor a variety of parameters in the wellbore environment. For example, during a treatment operation, it may be desirable to monitor a variety of properties of the treatment fluid such as viscosity, temperature, pressure, velocity, specific gravity, conductivity, fluid composition and the like. Transmission of this information to the surface in real-time or near real-time allows the operators to modify or optimize such treatment operations to improve the completion process. One way to transmit this information to the surface is through the use of an energy conductor which may take the form of one or more optical fibers.
In addition or as an alternative to operating as an energy conductor, an optical fiber may serve as a sensor. It has been found that an optical fiber may be used to obtain distributed measurements representing a parameter along the entire length of the fiber. Specifically, optical fibers have been used for distributed downhole temperature sensing, which provides a more complete temperature profile as compared to discrete temperature sensors. In operation, once an optical fiber is installed in the well, a pulse of laser light is sent along the fiber. As the light travels down the fiber, portions of the light are backscattered to the surface due to the optical properties of the fiber. The backscattered light has a slightly shifted frequency such that it provides information that is used to determine the temperature at the point in the fiber where the backscatter originated. In addition, as the speed of light is constant, the distance from the surface to the point where the backscatter originated can also be determined. In this manner, continuous monitoring of the backscattered light will provide temperature profile information for the entire length of the fiber.
Use of an optical fiber for distributed downhole temperature sensing may be highly beneficial during the completion process. For example, in a stimulation operation, a temperature profile may be obtained to determine where the injected fluid entered formations or zones intersected by the wellbore. This information is useful in evaluating the effectiveness of the stimulation operation and in planning future stimulation operations. Likewise, use of an optical fiber for distributed downhole temperature sensing may be highly beneficial during production operations. For example, during a production operation a distributed temperature profile may be used in determining the location of water or gas influx along the sand control screens. In a typical completion operation, a lower portion of the completion string including various tools such as sand control screens, fluid flow control devices, wellbore isolation devices and the like is permanently installed in the wellbore. As discussed above, the lower portion of the completion string may include various sensors, particularly, a lower portion of the optical fiber. After the completion process is finished, an upper portion of the completions string which includes the upper portion of the optical fiber is separated from the lower portion of the completion string and retrieved to the surface. This operation cuts off communication between the lower portion of the optical fiber and the surface. Accordingly, if information from the production zones is to be transmitted to the surface during production operations, a connection to the lower portion of the optical fiber must be reestablished when the production tubing string is installed.
It has been found, however, that wet mating optical fibers in a downhole environment is very difficult. This difficulty is due in part to the lack of precision in the axially movement of the production tubing string relative to the previously installed completion string. Specifically, the production tubing string is installed in the wellbore by lowering the block at the surface, which is thousands of feet away from the downhole landing location. In addition, neither the distance the block is moved nor the speed at which the block is moved at the surface directly translates to the movement characteristics at the downhole end of the production tubing string due to static and dynamic frictional forces, gravitational forces, fluid pressure forces and the like. The lack of correlation between block movement and the movement of the lower end of the production tubing string is particularly acute in slanted, deviated and horizontal wells. This lack in precision in both the distance and the speed at which the lower end of the production tubing string moves has limited the ability to wet mate optical fibers downhole as the wet mating process requires relatively high precision to sufficiently align the fibers to achieve the required optical transmissivity at the location of the connection.
Therefore, a need has arisen for an apparatus and method for wet connecting optical fibers in a subterranean wellbore environment. A need has also arisen for such an apparatus and method for wet connecting optical fibers that is operable to overcome the lack of precision in the axial movement of downhole pipe strings relative to one another. Further, a need has arisen for such an apparatus and method for wet connecting optical fibers that is operable to overcome the lack of precision in the speed of movement of downhole pipe strings relative to one another.
SUMMARY OF THE INVENTION
The present invention disclosed herein is directed to an apparatus and method for wet connecting downhole communication media in a subterranean wellbore environment. The apparatus and method of the present invention are operable to overcome the lack of precision in the axial movement of downhole pipe strings relative to one another. In addition, apparatus and method of the present invention are operable to overcome the lack of precision in the speed of movement of downhole pipe strings relative to one another. In carrying out the principles of the present invention, a wet connection apparatus and method are provided that are operable to control the connection speed of downhole connectors.
In one aspect, the present invention is directed to a method for controlling the connection speed of first and second downhole connectors in a subterranean well. The method includes positioning a first assembly in the well, the first assembly including the first downhole connector and a first communication medium; engaging the first assembly with a second assembly, the second assembly including the second downhole connector and a second communication medium; axially shifting an outer portion of the second assembly relative to an inner portion of the second assembly; and then operatively connecting the first and second downhole connectors to each other, thereby enabling communication between the first and second communication media.
In one embodiment, the method includes releasing a lock initially coupling the outer and inner portions of the second assembly. This step may be performed by radially inwardly compressing a collet assembly of the outer portion of the second assembly with an inner surface of the first assembly. In another embodiment, the method includes controlling the rate at which the outer and inner portions of the second assembly axially shift relative to one another with a resistance assembly. This step may be performed by metering a fluid through a transfer piston. In a further embodiment, the method includes anchoring the second assembly within the first assembly. This step may be performed by engaging a collet assembly of the outer portion of the second assembly with a profile of the first assembly. In yet another embodiment, the method may include disposing the first downhole connector of the first assembly at a location uphole of a packer of the first assembly. In any of the embodiments, the communication media may be optical fibers, electrical conductors, hydraulic fluid or the like. When the first communication medium is an optical fiber, this optical fiber may be operated as a sensor such as a distributed temperature sensor.
In another aspect, the present invention is directed to a method for controlling the connection speed of first and second fiber optic connectors in a subterranean well. The method includes positioning a first assembly in the well, the first assembly including the first fiber optic connector and a first optical fiber; engaging the first assembly with a second assembly, the second assembly including the second fiber optic connector and a second optical fiber; axially shifting an outer portion of the second assembly relative to an inner portion of the second assembly while metering a fluid through a transfer piston to control the rate at which the outer and inner portions of the second assembly axially shift relative to one another; and then operatively connecting the first and second fiber optic connectors to each other, thereby enabling light transmission between the optical fibers.
In a further aspect, the present invention is directed to an apparatus for controlling the connection speed of first and second downhole connectors in a subterranean well. The apparatus includes a first assembly that is positionable in the well. The first assembly includes the first downhole connector and a first communication medium. A second assembly includes the second downhole connector and a second communication medium. The second assembly has an outer portion and an inner portion that are selectively axially shiftable relative to one another such that upon engagement of the first assembly with the second assembly, the outer portion of the second assembly is axially shifted relative to the inner portion of the second assembly allowing the first and second downhole connectors to be operatively connected to each other, thereby enabling communication between the first communication medium and the second communication medium.
In one embodiment, the inner portion of the second assembly includes a lock and the outer portion of the second assembly includes a collet assembly. The lock initially couples the outer and inner portions of the second assembly together and the collet is operable to release the lock in response to being radially inwardly compressed by an inner surface of the first assembly. In another embodiment, the apparatus includes a resistance assembly that is positioned between the outer portion of the second assembly and the inner portion of the second assembly that controls the rate at which the outer and inner portions of the second assembly axially shift relative to one another by, for example, metering a fluid through a transfer piston. In a further embodiment, the outer portion of the second assembly includes a collet assembly and the first assembly includes a profile. In this embodiment, the collet assembly is operable to engage the profile to anchor the second assembly within the first assembly. In yet another embodiment, the first assembly includes a packer and the first downhole connector of the first assembly is positioned at a location uphole of the packer.
In yet another aspect, the present invention is directed to a method for controlling the disconnection speed of first and second downhole connectors in a subterranean well. The method includes establishing a predetermined tensile force between a first assembly and a second assembly in the well, the first assembly including the first downhole connector and a first communication medium, the second assembly including the second downhole connector and a second communication medium; axially shifting an outer portion of the second assembly relative to an inner portion of the second assembly; and operatively disconnecting the first and second downhole connectors from each other, thereby disabling communication between the first and second communication media.
In one embodiment, the method may include releasing an anchor of the second assembly from a profile in the first assembly. This step may be performed by radially inwardly compressing a collet assembly of the second assembly with an inner surface of the first assembly. In another embodiment, the method may include controlling the rate at which the outer and inner portions of the second assembly axially shift relative to one another with a resistance assembly. This step may be performed by metering a fluid through a transfer piston.
BRIEF DESCRIPTION OF THE DRAWINGS
For a more complete understanding of the features and advantages of the present invention, reference is now made to the detailed description of the invention along with the accompanying figures in which corresponding numerals in the different figures refer to corresponding parts and in which:
FIG. 1 is a schematic illustration of an offshore oil and gas platform operating an apparatus for controlling the connection speed of downhole connectors according to an embodiment of the present invention;
FIGS. 2A-2D are front views of consecutive axial sections of an apparatus for controlling the connection speed of downhole connectors in a running configuration according to an embodiment of the present invention;
FIGS. 3A-3D are cross sectional views of consecutive axial sections of an apparatus for controlling the connection speed of downhole connectors in a running configuration according to an embodiment of the present invention;
FIGS. 4A-4D are front views of consecutive axial sections of an apparatus for controlling the connection speed of downhole connectors in an anchored configuration according to an embodiment of the present invention; and
FIGS. 5A-5D are cross sectional views of consecutive axial sections of an apparatus for controlling the connection speed of downhole connectors in an anchored configuration according to an embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
While the making and using of various embodiments of the present invention are discussed in detail below, it should be appreciated that the present invention provides many applicable inventive concepts, which can be embodied in a wide variety of specific contexts. The specific embodiments discussed herein are merely illustrative of specific ways to make and use the invention, and do not delimit the scope of the invention.
Referring initially to FIG. 1 , an apparatus for controlling the connection speed of downhole connectors deployed from an offshore oil or gas platform is schematically illustrated and generally designated 10 . A semi-submersible platform 12 is centered over submerged oil and gas formation 14 located below sea floor 16 . A subsea conduit 18 extends from deck 20 of platform 12 to wellhead installation 22 , including blowout preventers 24 . Platform 12 has a hoisting apparatus 26 , a derrick 28 , a travel block 30 , a hook 32 and a swivel 34 for raising and lowering pipe strings, such as a substantially tubular, axially extending production tubing 36 .
A wellbore 38 extends through the various earth strata including formation 14 . An upper portion of wellbore 38 includes casing 40 that is cemented within wellbore 38 . Disposed in an open hole portion of wellbore 38 is a completion that includes various tools such as packer 44 , a seal bore assembly 46 and sand control screen assemblies 48 , 50 , 52 , 54 . In the illustrated embodiment, completion 42 also includes an orientation and alignment subassembly 56 that houses a downhole wet mate connector. Extending downhole from orientation and alignment subassembly 56 is a conduit 58 that passes through packer 44 and is operably associated with sand control screen assemblies 48 , 50 , 52 , 54 . Preferably, conduit 58 is a spoolable metal conduit, such as a stainless steel conduit that may be attached to the exterior of pipe strings as they are deployed in the well. In the illustrated embodiment, conduit 58 is wrapped around sand control screen assemblies 48 , 50 , 52 , 54 . One or more communication media such as optical fibers, electrical conducts, hydraulic fluid or the like may be disposed within conduit 58 . In certain embodiments, the communication media may operate as energy conductors including power and data transmission between downhole a location or downhole sensors (not pictured) and the surface. In other embodiments, the communication media may operate as downhole sensors.
For example, when optical fibers are used as the communication media, the optical fibers may be used to obtain distributed measurements representing a parameter along the entire length of the fiber such as distributed temperature sensing. In this embodiment, a pulse of laser light from the surface is sent along the fiber and portions of the light are backscattered to the surface due to the optical properties of the fiber. The slightly shifted frequency of the backscattered light provides information that is used to determine the temperature at the point in the fiber where the backscatter originated. In addition, as the speed of light is constant, the distance from the surface to the point where the backscatter originated can also be determined. In this manner, continuous monitoring of the backscattered light will provide temperature profile information for the entire length of the fiber.
Disposed in wellbore 38 at the lower end of production tubing string 36 are a variety of tools including seal assembly 60 and anchor assembly 62 including downhole wet mate connector 64 . Extending uphole of connector 64 is a conduit 66 that extends to the surface in the annulus between production tubing string 36 and wellbore 38 and is suitable coupled to production tubing string 36 to prevent damage to conduit 66 during installation. Similar to conduit 58 , conduit 66 may have one or more communication media, such as optical fibers, electrical conducts, hydraulic fluid or the like disposed therein. Preferable, conduit 58 and conduit 66 will have the same type of communication media disposed therein such that energy may be transmitted therebetween following the connection process. As discussed in greater detail below, prior to producing fluids, such as hydrocarbon fluids, from formation 14 , production tubing string 36 and completion 42 are connected together. When properly connected to each other, a sealed communication path is created between seal assembly 60 and seal bore assembly 46 which establishes a sealed internal flow passage from completion 42 to production tubing string 36 , thereby providing a fluid conduit to the surface for production fluids. In addition, as discussed in greater detail below, the present invention enables the communication media associated with conduit 66 to be operatively connected to the communication media associated with conduit 58 , thereby enabling communication therebetween and, in the case of optical fiber communication media, enabling distributed temperature information to be obtained along completion 42 during the subsequent production operations.
Even though FIG. 1 depicts a slanted wellbore, it should be understood by those skilled in the art that the apparatus for controlling the connection speed of downhole connectors according to the present invention is equally well suited for use in wellbore having other orientations including vertical wellbores, horizontal wellbores, multilateral wellbores or the like. Accordingly, it should be understood by those skilled in the art that the use of directional terms such as above, below, upper, lower, upward, downward and the like are used in relation to the illustrative embodiments as they are depicted in the figures, the upward direction being toward the top of the corresponding figure and the downward direction being toward the bottom of the corresponding figure. Also, even though FIG. 1 depicts an offshore operation, it should be understood by those skilled in the art that the apparatus for controlling the connection speed of downhole connectors according to the present invention is equally well suited for use in onshore operations. Further, even though FIG. 1 depicts an open hole completion, it should be understood by those skilled in the art that the apparatus for controlling the connection speed of downhole connectors according to the present invention is equally well suited for use in cased hole completions.
Referring now to FIGS. 2 and 3 , including FIGS. 2A-2D and FIGS. 3A-3D , therein is depicted successive axial section of an apparatus for controlling the connection speed of downhole connectors that is generally designated 100 . It is noted that FIGS. 2A-2D and FIGS. 3A-3D as well as FIGS. 4A-4D and 5 A- 5 D below are described with reference to optical fibers as the communication media. As discussed above, those skilled in the art will recognize that the present invention is not limited to this illustrated embodiment but instead encompasses other communication media including, but not limited to, electrical conductors and hydraulic fluid. Also, as described above, apparatus 100 is formed from certain components that are initially installed downhole as part of completion 42 and certain components that are carried on the lower end of production tubing string 36 . As illustrated in FIG. 2 , some the components carried on the lower end of production tubing string 36 have come in contact with certain components of completion 42 prior to connecting the respective wet mate connectors together. The entire apparatus 100 will now be described from its uphole end to its downhole end, first describing the exterior parts of the components carried on the lower end of production tubing string 36 , followed by the interior parts of the components carried on the lower end of production tubing string 36 then describing the components previously installed downhole as part of completion 42 .
Apparatus 100 includes a substantially tubular axially extending upper connector 102 that is operable to be coupled to the lower end of production tubing string 36 by threading or other suitable means. At its lower end, upper connector 102 is threadedly and sealingly connected to the upper end of a substantially tubular axially extending hone bore 104 . Hone bore 104 includes a plurality of lateral opening 106 having plugs 108 disposed therein. At its lower end, hone bore 104 is securably connected to the upper end of a substantially tubular axially extending connector member 110 . At its lower end, connector member 110 is securably connected to the upper end of an axially extending collet assembly 112 . Collet assembly 112 includes a plurality of circumferentially disposed anchor collets 114 , each having an upper surface 116 . In addition, collet assembly 112 includes a plurality of circumferentially disposed unlocking collets 118 . Further, collet assembly 112 includes a plurality of radially inwardly extending protrusions 120 and profiles 122 . At its lower end, collet assembly 112 is threadedly coupled to the upper end of a substantially tubular axially extending key retainer 124 . A portion of collet assembly 112 and key retainer 124 are both slidably disposed about the upper end of a substantially tubular axially extending key mandrel 126 . Key mandrel 126 includes a key window 128 into which a spring key 130 is received.
At its lower end, key mandrel 126 is threadedly coupled to the upper end of a substantially tubular axially extending spring housing 132 . Disposed within spring housing 132 is an axially extending spiral wound compression spring 134 . At its lower end, spring housing 132 is slidably disposed about the upper end of a substantially tubular axially extending connector member 136 . At its lower end, connector member 136 is threadedly coupled to the upper end of a substantially tubular axially extending splitter 138 . Splitter 138 includes an orientation key 140 disposed about a circumferential portion of splitter 138 . At its lower end, splitter 138 is coupled to the upper end of a substantially tubular axially extending fiber optic wet mate head 142 by threading, bolting or other suitable technique. Fiber optic wet mate head 142 includes a plurality of guide members 144 . In the illustrated embodiment, fiber optic wet mate head 142 has three fiber optic wet mate connectors 146 disposed therein. Each of the fiber optic wet mate connectors 146 has an optical fiber disposed therein. As illustrated, the three optical fibers associated with fiber optic wet mate connectors 146 passed through splitter 138 and are housed within a single conduit 148 that wraps around connector member 136 and extends uphole along the exterior of apparatus 100 . Conduit 148 is secured to apparatus 100 by banding or other suitable technique.
In the previous section, the exterior components of the portion of apparatus 100 carried by production tubing string 36 were described. In this section, the interior components of the portion of apparatus 100 carried by production tubing string 36 will be described. At its upper end, apparatus 100 includes a substantially tubular axially extending piston mandrel 200 that is slidably and sealingly received within upper connector 102 . Disposed between piston mandrel 200 and hone bore 104 is an annular oil chamber 202 including upper section 204 and lower section 206 . Securably attached to piston mandrel 200 and sealing positioned within annular oil chamber 202 is a transfer piston 208 . Transfer piston 208 includes one or more passageways 210 therethrough which preferably include orifices that regulate the rate at which a transfer fluid such as a liquid or gas and preferably an oil disposed within annular oil chamber 202 may travel therethrough. Preferably, a check valve may be disposed within each passageway 210 to allow the flow of oil to proceed in only one direction through that passageway 210 . In this embodiment, certain of the check valves will allow fluid flow in the uphole direction while other of the check valves will allow fluid flow in the downhole direction. In this manner, the resistance to flow in the downhole direction can be different from the resistance to flow in the uphole direction which respectively determines the speed of coupling and decoupling of the downhole connectors of apparatus 100 . For example, it may be desirable to couple the downhole connectors at a speed that is slower than the speed at which the downhole connectors are decoupled.
Disposed within annular oil chamber 202 is a compensation piston 212 that has a sealing relationship with both the inner surface of hone bore 104 and the outer surface of piston mandrel 200 . At its lower end, piston mandrel 200 is threadedly and sealingly coupled to the upper end of a substantially tubular axially extending key block 214 . Key block 214 has a radially reduced profile 216 into which spring mounted locking keys 218 are positioned. Locking keys 218 include a profile 220 . At its lower end, key block 214 is threadedly and sealingly coupled to the upper end of a substantially tubular axially extending bottom mandrel 222 . Bottom mandrel 222 includes a groove 224 . A pickup ring 226 is positioned around bottom mandrel 222 . Positioned near the lower end of bottom mandrel 222 is a key carrier 228 that has a no go surface 230 . Disposed within key carrier 228 is a spring mounted locking key 232 . Positioned between key carrier 228 and bottom mandrel 222 is a torque key 234 . At its lower end, bottom mandrel 222 is threadedly and sealingly coupled to the upper end of a substantially tubular axially extending seal adaptor 236 . At its lower end, seal adaptor 236 is threadedly and sealingly coupled to the upper end of one or more substantially tubular axially extending seal assemblies (not pictured) that establish a sealing relationship with an interior surface of completion 42 .
In the previous two sections, the components of apparatus 100 carried by production tubing string 36 were described. Collectively, these components may be referred to as an anchor or anchoring assembly. In this section, the components of apparatus 100 installed with completion 42 will be described. Apparatus 100 includes an orientation and alignment subassembly 300 that includes a locating and orienting guide 302 that is illustrated in FIG. 3 but has been removed from FIG. 2 for clarity of illustration. Locating and orienting guide 302 includes a locking profile 304 , a groove 306 and a plurality of fluid passageways 308 . In addition, locating and orienting guide 302 includes a receiving slot 310 . Disposed within locating and orienting guide 302 , orientation and alignment subassembly 300 includes a top subassembly 312 that supports a fiber optic wet mate holder 314 . In the illustrated embodiment, disposed within wet mate holder 314 are three wet mate connectors 316 . At its upper end, wet mate holder 314 includes a plurality of guides 318 . Positioned between top subassembly 312 and locating and orienting guide 302 is a key 320 . At its lower end, top subassembly 312 is threadedly and sealingly coupled to the upper end of a substantially tubular axially extending splitter 322 . At its lower end, splitter 322 is coupled to the upper end of one or more substantially tubular axially extending packers 324 by threading, bolting, fastening or other suitable technique. Each of the fiber optic wet mate connectors 316 has an optical fiber disposed therein. As illustrated, the three optical fibers associated with fiber optic wet mate holder 314 pass through splitter 322 and are housed within a single conduit 326 that extends through packer 324 and is wrapped around sand control screens 48 , 50 , 52 , 54 as described above to obtain distributed temperature information, for example.
The operation of the apparatus for controlling the connection speed of downhole connectors according to the present invention will now be described. After the installation of completion 42 in the wellbore and the performance of any associated treatment processes wherein the optical fibers associated with completion 42 and companion optical fibers associated with the service tool string may deliver information to the surface, the service tool string is retrieved to the surface. In this process, the optical fibers associated with completion 42 and the optical fibers associated with the service tool string must be decoupled. In order to reuse the optical fibers associated with completion 42 during production, new optical fibers must be carried with production tubing string 36 and optically coupled to the optical fibers associated with completion 42 .
In the present invention, conduit 148 is attached to the exterior of production tubing string 36 and extends from the surface to the anchor assembly. One or more optical fibers are disposed within conduit 148 which may be a conventional hydraulic line formed from stainless steel or similar material. The anchor assembly is lowered into the wellbore until the seal assemblies on its lower end enter completion 42 . As production tubing string 36 is further lowered into the wellbore, orientation key 140 contacts the inclined surfaces of locating and orientating guide 302 . This interaction rotates the anchor assembly until orientation key 140 locates within slot 310 which provides a relatively coarse circumferential alignment of fiber optic wet mate head 142 with fiber optic wet mate holder 314 . The anchor assembly now continues to travel downwardly in completion 42 until no go surface 230 of key carrier 228 contacts an upwardly facing shoulder 328 of top subassembly 312 . Prior to contact between no go surface 230 and upwardly facing shoulder 328 , guides 144 of fiber optic wet mate head 142 and guides 318 of fiber optic wet mate holder 314 interact to provide more precise circumferential and axially alignment of the assemblies.
Once no go surface 230 contacts upwardly facing shoulder 328 , further downward motion of the inner components of the anchor assembly stops. In this configuration, as best seen in FIGS. 2A-2D and 3 A- 3 D, unlocking collets 118 are radially inwardly shifted due to contact with the inner surface of locating and orienting guide 302 . This radially inward shifting causes the inner surfaces of unlocking collets 118 to contact unlocking keys 218 and compress the associated springs causing unlocking keys 218 to radially inwardly retract. In the retraced position, radially inwardly extending protrusions 120 are released from profile 220 , thereby decoupling the outer portions of the anchor assembly from the inner portions of the anchor assembly. Relative axially movement of the outer portions of the anchor assembly and the inner portions of the anchor assembly is now permitted.
As continued downward force is placed on the anchor assembly by applying force to the production tubing string 36 , upper connector 102 is urged downwardly relative to piston mandrel 200 . The movement of upper connector 102 relative to piston mandrel 200 is resisted, however, by a resistance member. In the illustrated embodiment, the resistance member is depicted as transfer piston 208 and the fluid within annular oil chamber 202 . Specifically, the speed at which upper connector 102 can move relative to piston mandrel 200 is determined by the size of the orifice within passageway 210 of transfer piston 208 as well as the type of fluid, including liquids, gases or combinations thereof, within annular oil chamber 202 . As the downward force is applied to upper connector 102 , the fluid from upper section 204 of annular oil chamber 202 transfers to lower section 206 of annular oil chamber 202 passing through passageway 210 . In this manner, excessive connection speed of fiber optic wet mate connectors 146 and fiber optic wet mate connectors 316 is prevented. Even though the resistance member has been described as transfer piston 208 and the fluid within annular oil chamber 202 , it should be understood by those skilled in the art that other types of resistance members could alternatively be used and are considered within the scope of the present invention, including, but not limited to, mechanical springs, fluid springs, fluid dampeners, shock absorbers and the like.
As best seen in FIGS. 4A-4D and 5 A- 5 D, continued downward force on upper connector 102 not only enables connection of fiber optic wet mate connectors 146 and fiber optic wet mate connectors 316 , but also, compresses the outer components of the anchor assembly and locks the anchor assembly within completion 42 . Once the connection between fiber optic wet mate connectors 146 and fiber optic wet mate connectors 316 is established, thereby permitting light transmission between the optical fibers therein, continued downward force on upper connector 102 compresses spring 134 . As spring 134 is compressed, spring housing 132 telescopes relative to connector member 136 . This shortening of the outer components of the anchor assembly allows spring key 130 to engage groove 224 of bottom mandrel 222 . Once spring key 130 has radially inwardly retracted, the outer components of the anchor assembly further collapse as collet assembly 112 and key retainer 124 telescope relative to key mandrel 126 . This shortening allows anchor collets 114 to engage locking profile 304 which couples the anchor assembly within completion 42 . Also, this shortening allows unlocking collets 118 to engage groove 306 which relaxes unlocking collets 118 . In addition, the inner portions of the anchor assembly are independently secured within completion 42 as extension 150 on the lower end of fiber optic wet mate head 142 is positioned under locking key 232 such that locking key 232 engages profile 330 of top subassembly 312 .
In this configuration, not only are fiber optic wet mate connectors 146 and fiber optic wet mate connectors 316 coupled together, there is a biasing force created by compressed spring 134 that assures the connections will not be lost. Specifically, compressed spring 134 downwardly biases connector member 136 which in turn applies a downward force on splitter 138 and fiber optic wet mate head 142 . This force prevents any decoupling of fiber optic wet mate connectors 146 and fiber optic wet mate connectors 316 . In addition, the interaction of surface 116 of anchor collets 114 with locking profile 304 of locating and orienting guide 302 prevents separation of the anchoring assembly and the completion 42 . If it is desired to detach production tubing string 36 from completion 42 , a significant tensile force must be applied to production tubing string 36 at the surface, for example, 20,000 lbs. This force is transmitted via upper connector 102 , hone bore 104 and connector member 110 to collet assembly 112 . When sufficient tensile force is provided, anchor collets 114 will release from locking profile 304 . Thereafter, the outer portions of anchor assembly that were telescopically contracted can be telescopically extended including the release of energy from spring 134 . In order to separate fiber optic wet mate connectors 146 and fiber optic wet mate connectors 316 , the outer portions of the anchor assembly must be shifted relative to the inner portions of the anchor assembly. The rate of the axial shifting is again controlled by the metering rate of fluid through transfer piston 212 . After the outer portions of the anchor assembly have been shifted relative to the inner portions of the anchor assembly, extension 150 no longer supports locking key 232 in profile 330 . As this point the entire anchor assembly may be retrieved to the surface.
While this invention has been described with reference to illustrative embodiments, this description is not intended to be construed in a limiting sense. Various modifications and combinations of the illustrative embodiments as well as other embodiments of the invention, will be apparent to persons skilled in the art upon reference to the description. It is, therefore, intended that the appended claims encompass any such modifications or embodiments. | An apparatus ( 100 ) for controlling the connection speed of downhole connectors ( 316, 146 ) in a subterranean well. The apparatus ( 100 ) includes a first assembly that is positionable in the well. The first assembly includes a first downhole connector ( 316 ) and a first communication medium. A second assembly includes a second downhole connector ( 146 ) and a second communication medium. The second assembly has an outer portion and an inner portion. The outer portion is selectively axially shiftable relative to an inner portion, such that upon engagement of the first assembly with the second assembly, the outer portion of the second assembly is axially shifted relative to the inner portion of the second assembly allowing the first and second downhole connectors ( 316, 146 ) to be operatively connected to each other, thereby enabling communication between the first communication medium and the second communication medium. | 4 |
FIELD OF THE INVENTION
[0001] The present invention relates to novel solvent systems capable of dissolving bituminous buildup on paving and roofing equipment. These solvents are characterized in being non-hazardous, non-toxic, and environmentally safe. Mixtures comprising noncyclic monoterpenes and anionic detergents provide effective cleaning and conditioning.
BACKGROUND OF THE INVENTION
[0002] Bituminous products are widely used in the construction field, and constitute one of the major commodity products in building and road construction. These materials are derived from the residue remaining after crude oil is refined to remove various distillates. Over the past twenty years, there have been many innovations in bituminous materials used in roofing and paving. The principle objectives of these is developments are to increase strength and durability, ductility, reduce “creep”, cracking, and surface wear. A typical asphalt shingled roof requires replacement after 12-18 years, and road damage to asphalt may be detected within even the first year of paving. New compositions have substantially extended the lifespan of these materials
[0003] Many of the new asphalt materials contain synthetic polymers to create chemical links (both covalent and non-covalent interactions) between the long chain hydrocarbons, thus providing molecular strength. U.S. Pat. No. 5,556,900 discloses a thermoplastic polymer-linked asphalt in which the asphalt is reacted with an epoxide polymer resulting in a composition with low gelation, high emulsion forming capacity, and improved rheology. Heat treatment at 135 degrees C., results in covalent bonding between the polymer and the asphalt. In other polymer-containing bitumens, there is typically non-covalent adhesion binding of components.
[0004] For example, U.S. Pat. No. 5,473,000 teaches a method for improving bitumen by adding to asphalt a thermoplast or thermoelastomer, and a wood resin, resulting in enhanced binding properties. A linear polyethylene modified asphaltic composition is disclosed in U.S. Pat. No. 4,868,233, which has improved storage stability and creep resistance. Another polymer additive approach is disclosed in U.S. Pat. No. 5,322,867 for a bituminous mixture containing a polymer comprising one block of a conjugated diolefin methacrylate and a block of a functionalized acrylic monomer, giving improved properties over neat asphalt.
[0005] Some of the most significant developments in asphalt and tar composition involve various strategies for combining the strength and resiliency of latex polymers with bituminous materials. U.S. Pat. Nos. 4,485,201 and 5,436,285 disclose incorporation of finely divided rubber into asphalt compositions. In a variation, U.S. Pat. No. 5,811,477 utilizes reclaimed rubber particles, latex rubber, preferably styrene butadiene, and an aqueous asphalt emulsion to achieve low temperature processing, thereby reducing environmental contamination from latex volatiles.
[0006] U.S. Pat. Nos. 5,451,621 and 5,973,037 teach the infusion of particular latex polymers characterized as styrene-ethylene-butylene-styrene block copolymers into bituminous products, including asphalt, to raise the softening point of the blend and increase resistance to ultraviolet radiation, ozone, and fatigue. In yet another application of rubber in the asphalt art, U.S. Pat. No. 5,704,971 discloses the pretreatment of crumb rubber with peroxide, adding the treated rubber to asphalt in the presence of a compatibilized binder to produce an asphalt having improved settling properties of the binder, and reduced tendency to ravel.
[0007] While the objectives of improved durability, ductility, strength, and other related performance improvements, modification of bituminous substances has brought about new problems. The same molecular interactions which achieve enhanced stability and binding efficiency of the asphalt components, especially in the class of latex polymer blends known as SuperPave, also render the material extremely difficult to remove from paving equipment such as asphalt distributors and oilers, spreaders and the like, roofing manufacturing equipment and applications equipment. The buildup of these materials on equipment, particularly painted and bare metallic surfaces, leads to uneven dispensing, plugged nozzles, and impaired release of asphalt from distributors and spreaders. In many instances uneven distribution of asphalt in pavement requires repaving at substantial cost to the industry.
[0008] Classically, equipment has been cleaned by the use of common petroleum distillates such as kerosene, diesel fuel, or more purified fractions, and wood resin compounds such as turpentine. Usually cleaning with these substances requires mechanical intervention as by brushing, rubbing with cloth or abrasives. Use of such conventional substances has led to environmental contamination and exposure of cleanup personnel to toxic, and even carcinogenic substances. Moreover, the extreme intractability of the advanced polymer blended bitumens to conventional cleaning solvents increases the volumes needed to soften and remove them from machinery surfaces. Incomplete removal of the asphalt results from the difficulty of conventional solvents to penetrate the asphalt matrix. This increases costs of cleanup to the industry, in terms of time and materials, and machine efficiency.
[0009] Much attention has been given to development of asphalt release agents that preventing sticking of bituminous materials to machinery. U.S. Pat. No. 5,900,048 discloses a release composition combining lethicin with a dispersing agent such as propylene glycol ethers or ether acetates. Other release agents have been proposed such as a combination of polycycloaliphatic amines and polyalkylene glycols (U.S. Pat. No. 5,961,730), cleaning by hydrogen peroxide together with iron catalysts (U.S. Pat. No. 5,725,687), fatty acids in combination with preferably an anionic surfactant (U.S. Pat. No. 5,494,502, and a water based solution of magnesium chloride, a phosphate ester, an anionic alcohol surfactant (U.S. Pat. No. 5,322,554).
[0010] All of the foregoing release technologies have as a common strategy, forming a slippery barrier coating on a metal surface to prevent adhesion of asphalt, thus allowing it to slide readily from the treated surface. None of these compounds can be expected to appreciably penetrate the asphalt itself, except as a softener at the immediate undersurface. Thus, effective removal of asphalt already set on machinery is not addressed. A need exists for an effective asphalt removal agent, especially for modern bituminous polymer-containing formulations.
SUMMARY OF THE INVENTION
[0011] Immediately after compounding, asphalt is ductile and somewhat flowable, but stiffens and becomes less compactable as it sets. When fully set, asphalt is a dense mass, made more cohesive and fibrous by inclusion of polymer strands and other additives. These asphalts provide a formidable barrier to penetration of water and organic solvents. Such compositions bind tightly to solid surfaces, and can be scraped off only with great difficulty.
[0012] It is therefore an object of the present invention to provide an agent capable of penetrating and dissolving bitumens in situ without recourse to mechanical interventions such as chipping, wiping, brushing, or grinding. It is a further object to provide an agent which is easily applied to tar and asphalt coated metal or plastic surfaces without damage to the surface. Such agent will be fast acting and result in effectively complete removal. Most importantly, it is an object of the invention to provide an essentially harmless agent which is environmentally safe, non-toxic to clean-up personnel, and biodegradable.
[0013] The present composition comprises a mixture of one or more monocyclic monoterpenes (preferably one or more para-menthane dienes) which act as a carrier solvent, and a non-ionic detergent having sufficient hydophobicity to penetrate the bitumen matrix, and sufficient hydrophilicity to be soluble in the carrier. The detergent is preferably selected from alkylphenol ethoxylates and alkyl alcohol ethoxylates, or combinations of these substances. The detergent content is at least 2% by weight (w/w) but may vary from about 2% (w/w) to about 12% w/w).
[0014] The alkylphenol ethoxylates of the present invention comprise linear hydrocarbon moieties of chain length 1-13 carbon atoms and ethoxy repeat units ranging linearly from 1 to 23 groups. The structure is defined by the following formula:
[0015] wherein R is a linear alkyl radical, n is an integer 1-12, and x is an integer 2-23.
[0016] The alkyl alcohol ethoxylates of the invention have a structure defined by the formula: CH 3 (CH 2 ) x —CH 2 —O(CH 2 CH 2 O) y H wherein x is an integer 2-16 and y is an integer 2-14.
[0017] According to the method of the present invention, bituminous material may be effectively removed from solid surfaces to which they are bound, by applying to such surfaces the compositions disclosed herein, allowing the solvent compositions to incubate at temperatures ranging from about 1 degrees Fahrenheit (F.) to about 150 degrees F. on the surface of the adherent bitumen for at least 2 minutes up to about 1hour, and rinsing with water. The application step may be repeated one or more times prior to a final water rinse.
[0018] In other embodiments, the present invention provides methods for removing asphalt or tar from a solid surface comprising providing a solid surface having tar or asphalt thereon and an undiluted mixture of a para-menthane diene and at least 2% w/w of a surfactant selected from the group consisting of an alkylphenol ethoxylate and an alkyl alcohol ethoxylate and combinations thereof; and applying the undiluted mixture of a para-menthane diene and at least 2% w/w of a surfactant selected from the group consisting of an alkylphenol ethoxylate and an alkyl alcohol ethoxylate and combinations thereof to the surface under conditions such that the tar or asphalt is removed.
BRIEF DESCRIPTION OF THE DRAWING
[0019] [0019]FIG. 1 is rectilinear plot showing the extent of asphalt removal as a function of the detergent content of the removal composition.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0020] In bitumen removal from equipment surfaces, the principal challenge is to penetrate the adherent material. Since asphalt and tar are endogenous to and ultimately obtained from crude oil, it has been assumed that the lighter refined fractions of oil would be the solvents of choice in “resolubilizing” the asphalt and tar fractions; hence, the widespread use petroleum distillates in cleaning tar and asphalt laden machinery. In addition to kerosene, distilled spirits, fuel oil, and diesel fuel, a few commercially formulated products have been on the market. Most of these products contain petroleum distillates immisible in water, and Applicant believes that an aqueous based detergent system may have been used. None of these are fully effective.
[0021] The present composition contains neither petroleum distillates nor water. However, the carrier monocyclic monoterpenes are highly hydrophilic and miscible in water. Thus, the water rinse carries away the phase compatible carrier after the dissolved bitumen has been absorbed by the hydrophobic alkyl moiety of the surfactant. While Applicant does not wish to be bound by any particular theory, it is believed that the hydrophilic moiety of the surfactant serves to anchor the molecule bearing its hydrocarbon absorbed hydrophobic moiety to the carrier stream.
[0022] The monocyclic monoterpenes belong to the family of substances known as “essential oils”. These compounds were distilled from aqueous infusions of various plant tissues such as flowers, fruits and leaves. The monocylic monoterpenes have the general menthane structure:
[0023] Some fourteen diene isomers having the para-menthane skeletal structure are possible, but only six occur in nature. In the present invention, three of the naturally occurring isomers are preferred: limonene (either as d-limonene or dl-limonene (dipentene)), terpinolene, and gama-terpinene. The isopropenyl-1-methyl cyclohexenes as a class are highly preferred and are functionally equivalent in the present composition. Limonene (4-isopropenyl-1-methyl-cyclohexene) is most preferred because of its excellent handling and blending properties, pleasant fragrance, and commercially available quantities.
[0024] Although the carrier properties of all the naturally-occurring monocyclic monoterpenes are expected to be similar (they have similar boiling points, solvency characteristics, and chemical properties), the aliphatic, un-derivativized isomers (such as the preferred class, the isopropenyl-1-methyl cyclohexenes) are much preferred over those having side chains appended to the pentane ring. “Un-derivatized” isomer means an aliphatic chemical structurally characterized in having a para-pentane ring and two double bonds.
[0025] Also included in the scope of the present invention are mixtures of para-pentane diene isomers obtained by molecular rearrangments catalyzed by acids, bases, or absorption onto surfaces such as silica gel. Such catalytic rearrangments are well known in fatty acid chemistry and may favor predominance of conjugated isoforms. Any such mixtures are suitable for use in the present composition.
[0026] Of the dozens of potential surfactant candidates, the alkylphenol ethoxylates and alkyl alcohol ethoxylates were found in the present invention to have superior cleaning and stability properties. Being nonionic they are highly compatible with the non-ionic para-menthane diene carriers.
[0027] The preferred class of alkylphenol ethoxylates are linear molecules having a linear alkyl radical of 2 to 13 methylene groups, linked through a phenolic radical to an ethoxy chain of 2 to 23 linearly repeating units. The choice of alkyl and ethoxy chain length is influenced somewhat by the composition of the bitumen. The preferred surfactant is the 1-nonylphenol-6-ethoxylate having an average of 9.5 ethoxy groups. This material is readily available commercially, and known in the art as SURFONIC™ N-95, manufactured by the Huntsman Corporation.
[0028] A second class of preferred surfactants are the alkyl alcohol ethoxylates having a formula: CH 3 (CH 2 ) x CH 2 —O(CH 2 CH 2 O) y H wherein x is an integer from 2 to 16 and y is an integer 2 to 23. In a preferred compound x is 14 and y is 8, and is known in the art as L24-8. A series of compounds of different alkyl and ethoxy chain length are commercially available from Huntsman Corporation.
[0029] The surfactant may be added to carrier at concentrations up to 20% without appreciably altering viscosity and coating properties. However, the cleaning action is optimal between 2 and 6% w/w. Although cleaning efficacy has been tested up to 12%, no apparent advantage is served at the higher concentrations. Therefore, any concentration of surfactant is encompassed by the invention up to about 20%, a working range of at least about 2% up to about 10% is highly efficacious. Higher concentrations contribute little except higher costs of manufacture.
[0030] In the event that it is suspected that a surfactant of different alkyl or ethoxy chain length may improve performance, some minor experimentation may be carried out by those skilled in the art. In general, if a greater degree of hydrophobicity is desired, it is recommended that the ethoxy chain length be extended also. In a particular application, if a longer alkyl chain is employed, a 9.5 unit ethoxy chain should be tested first. If no clouding of the carrier is detected, the composition can be used directly. Such tests can readily be carried out in the field, or by adopting the laboratory scale assay set forth in the Examples. There will be no need of undue experimentation, as the tests are easy to perform, and a wide range of surfactants of the disclosed classes are commercially available.
[0031] Production of commercial quantities of the present composition is simple and straightforward. The carrier is placed in a mixing vessel, a predetermined amount of surfactant is added, and the components are blended to uniformity by mechanical agitation, or by a recirculating pump.
[0032] In the method of the present invention asphalt, tar or other bituminous material can be removed effectively from a solid surface by contacting the surfaces with the cleaning composition, incubating at 1-150 degrees F. for 3-10 minutes, applying a second or subsequent coating of the solvent, incubating for another or subsequent 3-10 minute period, and finally, rinsing with water. Contacting is most conveniently achieved a by simple spray, taking care to cover all exposed surfaces. An ordinary garden sprayer available at most ordinary hardware stores is quite adequate. Alternatively, application may be made by wiping, sponging, dipping or submerging small parts, tools, or pieces of machinery, and maintaining the exposure for commensurate periods, followed by a water rinse. Mechanical intervention as by rubbing, scrubbing, wire brushing, and the like is unnecessary, and may interfere with the solvent action. Another application contemplated by the invention is removal of crude oil buildup on oil rigs, and drilling parts.
[0033] The present composition is effective for removing bituminous residues, even in situations where machinery maintenance has been neglected and the deposits tar, asphalt, and oil have been allowed to build up over time. All manner of solid surfaces may be cleaned including metal, painted metal, certain plastics, glass, ceramics, wood, natural or synthetic fabric. It is safe for contact with skin since it is non-corrosive, non-toxic, and non-irritating. Caution should be exercised in contacting certain plastics. It is safe for polyethylene or polyolefin plastics but it will dissolve polycarbonate and polystyrene plastics. In the water rinse step, immersion or rinsing by direct spray is adequate, although the use of a pressure spray 100-300 psi is recommended, and a high pressure spray of greater than 1000 psi is preferred.
[0034] Other advantages of the present invention will be apparent from the Examples which follow.
EXAMPLES
[0035] After numerous field tests of the present composition were conducted, and efficacy in tar and asphalt removal was reproducibly ascertained, a laboratory scale assay was designed to quantitate cleaning efficiency in comparison with conventional cleaning agents, and to optimize the amount of surfactant to be added to the carrier.
Example 1
[0036] A. Preparation of Test Strips
[0037] The assay utilizes test strips of stainless steel with dimensions 1.5 inches×2.0 inches×{fraction (1/32)} inches. Immersions in solvents were carried out by placing the strips in clamps and immersing two thirds of the total area of the strip. This provides a total uniform area of exposure of 2.0 square inches (the {fraction (1/32)} inch thickness of the strip was disregarded. The strips were desiccated and weighed with the clamp assembly, so that the strip itself would not be handled.
[0038] The asphalt used in these experiments was a standard commercially available material containing latex polymers called CRS28 manufactured by Patterson Oil Company, Sullivan, Mo. Upon procurement, each batch was cured by heating in a conventional laboratory oven for 7 days at 200 degrees F.
[0039] A bath of the cured latex polymer-containing SuperPave asphalt was heated to 175-180 degrees, F. The strips were immersed in the molten asphalt to provide 2.0 square inches of exposure. Exposure time was 2-3 seconds. The strips were cooled to room temperature and desiccated for 24 hours, and weighed. Each data point is the arithmetic average of ten strips treated identically.
[0040] B. Assay
[0041] The strips were immersed in the test solvents so that the entire asphalt coated areas were exposed to the solvent. The strips were withdrawn from the solution after 60 seconds and drained for 2 minutes. They were again immersed for 60 seconds and withdrawn. The strips were allowed to dry at room temperature for 2 hours and desiccated overnight. Dissections were performed in an ordinary bell jar in the presence of a standard commercial desiccant. The test strips were then reweighed. The data expressed in percent by weight of removal was calculated by subtracting the weight of the treated strip from the weight of the untreated strip and dividing by the weight of the untreated strip.
[0042] In this series of test, varying concentrations of Surfonic™ N-95 in d-limonene carrier were assayed for percent asphalt removal. The results are as follows:
Concentration surfactant Percent Removal 0.0 26.10 2.0 30.74 2.5 32.63 3.0 33.84 3.5 34.96 4.0 35.75 4.5 36.21 5.0 37.16 5.5 38.02 6.0 40.70 12.0 42.68
[0043] The results indicate that at concentrations of surfactant as low as 2 percent, there is a consistent increase in the amount of asphalt removed up to about 40%. Doubling the concentration at 6% does not improve removal appreciably, so that a range of 2% to 6% is optimal. FIG. 1 is a rectilinear plot of the above data, indicating that a concentration greater than 2% significantly enhances penetration of the carrier into the asphalt.
Example 2
[0044] A control experiment was conducted according to the same test protocol. AT10 is a product manufactured by Smith Systems Manufacturing and is believed by its physical properties to be a mixture of petroleum distillates. This product was compared with kerosene, diesel fuel and naphthalene. The percents of asphalt removal were 9.99, 9.17, 9.42, and 9.37 respectively. | A non-toxic, non-hazardous, environmentally safe composition provides an effective, fast acting cleaning solution for removal of tar, oils, asphalt and other bituminous materials from industrial equipment surfaces. The composition is a mixture of a carrier monocyclic monoterpene and a nonionic surfactant such as an alkylphenol ethoxylate. The mixture is applied directly to surfaces to be cleaned, and rinsed with water in the absence of mechanical intervention. | 2 |
FIELD OF THE INVENTION
[0001] This invention relates to a chimeric nucleotide sequence encoding peptides with antimicrobial activity.
BACKGROUND OF THE INVENTION
[0002] Antimicrobial peptides (AMP) are found in nature and have been isolated from several organisms, including animals and plants. In recent years, these molecules have shown important anti-pathogenic activity against Gram positive and Gram negative bacteria and fungi. AMPs are usually composed of 12-50 cationic and amphipathic amino acids (Broekaert et al., 1997; Zasloff, 2002, Marshall and Arenas, 2003). The natural AMPs are divided into groups characterized by peptides formed by β sheets, α-helices, extended structures and helix loop or loop structures, and of them, the first two are the most abundant (Dathe et al., 1999; Gao et al., 2000; Lehrer and Ganz, 2002; Bulet et al., 2004). The interaction between AMPs and their target cells is markedly influenced by factors such as the type and scope of their structure, cationicity, hydrophobicity, amphipathicity and amino acid sequence (Yeaman and Yount, 2003; Jenssen et al., 2006; Soltani et al., 2007). More than 2300 peptides have been described, and information on their structures, properties and mechanisms of action can be found in databases such as APD, ANTIMIC and AMPer.
[0003] Recently, AMPs have received attention as new substitutes for conventional pesticides and antibiotics as pathogens do not develop resistance to them because of their mechanism of action (Yeaman and Yount, 2003). However, the use of peptides as alternative drugs has encountered some difficulties, particularly the low recovery obtained after extraction from the tissue of origin. Therefore, their acquisition by chemical synthesis or the expression of the protein using a recombinant microorganism strategy has become necessary for further studies. Interestingly, synthetic analogs or AMP derivatives have been successfully developed based on natural peptides, generating significant improvements in their antimicrobial activity.
[0004] Most marine invertebrates are fixed to a substrate. Due to this sedentary condition, these organisms have evolved effective antimicrobials mechanisms, including AMPs (Tincu and Taylor, 2004). AMPs have been purified mainly from mollusks such as mussels, oysters, scallops and gastropods. Arenas et al. (2009) obtained and characterized an AMP native to a Chilean oyster ( A. purpuratus hemocytes) via chemical synthesis. This new molecule (Ap-S) showed the presence of a polyproline type secondary structure, with a reduced number of β sheets due to the differential distribution of hydrophobic and hydrophilic residues in two well-defined zones in the N- and C-termini, compared with the native peptide (Ap). Ap-S showed no cytotoxic effect in the fish cell line CHSE-214. These findings for the newly generated Ap-S molecule make its evaluation for various biotechnological applications into a reasonable option, including its exogenous application to control important plant pathogens. In this regard, the scaled-up synthesis of this peptide becomes important for potential industrial applications.
[0005] This application describes the design and use of a chimeric gene encoding the recombinant version of Ap-S (rAps) which is expressed in E. coli strain BL21 and in Nicotiana tabacum. The results of the evaluation of rAp-S against plant pathogens, exemplified in the fungi Trichoderma harzianum, Botrytis cinerea, Fusarium oxysporum and Alternaria sp., in the Gram positive bacterium Clavibacter michiganensis and in the Gram negative bacterium Xanthomona campestris, indicated that the mid-high scale production of this peptide leads to the production of a biologically active AMP that can be successfully used with these types of phytopathogens.
[0006] The first objective of the invention is to provide a nucleotide sequence encoding recombinant antimicrobial peptides of Ap-S with antifungal and bactericidal activity.
[0007] The second objective of the invention is to provide antimicrobial peptides with a broad activity spectrum.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 : Method of cloning in a suitable vector for the expression of the peptide in E. coli.
[0009] FIG. 2 : Method of cloning in a suitable vector for the expression of the peptide in plants or plant cells transformed using A. tumefaciens as an agent.
[0010] FIG. 3 : Method of cloning in a suitable vector for the expression of the peptide in a plant with A. tumefaciens as a vector.
[0011] FIG. 4 : Growth inhibition assays of Xanthomona campestris (G−) at different peptide concentrations. The maximum inhibition was reached between 2,000 and 4,000 μg/L.
[0012] FIG. 5 : Growth inhibition assays of Clavibacter michiganensis (G+) at various peptide concentrations. The maximum inhibition was reached between 12,500 and 15,500 μg/L.
[0013] FIG. 6 : Assay of the total protein extract from four lines of transgenic Nicotiana tabacum. The plates show growth inhibition halos on a lawn of T. harzianum.
DETAILED DESCRIPTION OF THE INVENTION
[0014] The present invention relates to the generation of a nucleotide sequence encoding antimicrobial peptides.
[0015] The technical basis of the present invention is that despite knowledge of the existence of peptides with antimicrobial activity for eukaryotic organisms such as shellfish, only a small amount of peptide can be extracted from the animal tissue. This limitation has forced us to look for alternative techniques of production, such as chemical synthesis, which despite allowing the generation of greater amounts of peptide, is limited by its high cost. An alternative is the use of genetic engineering and heterologous expression systems to produce appropriate amounts in recombinant organisms. The advantage of this alternative technique is that it can produce greater amounts of peptide that will allow a more complete characterization and the actual evaluation of their biotechnological potential. However, this developmental pathway has some difficulties due to the presence of too many possible combinations of nucleotides derived from codon use to correctly define a final active peptide.
[0016] The present invention provides a synthetic gene for the AMP, Ap-S, which enables the production of large amounts of the peptide and raises its projection for use in various industrial applications, such as agriculture.
[0017] To obtain adequate amounts of the rAp-S peptide, we proceeded to design the synthetic gene and establish a cloning strategy for a synthetic sequence in an expression vector to produce synthetic peptides that are suitable for controlling fungi and bacteria and to produce synthetic peptides in quantities sufficient for use as antipathogenic agents for activities such as agriculture, veterinary practice and/or medicine.
EXAMPLES
Example 1
[0018] Design of the Synthetic Gene: The Ap-S cDNA was designed using the reverse-translation of the sequence of 31 amino acids (MPVGIVIAPKKSPFTAKKPGPVLSGVKAGPG) (SEQ ID N° 9) previously described based on Argopecten purpuratus hemocytes. Using GCUA software (Fuhrmann y cols., 2004) and codons from E. coli, a synthetic gene for rApS (SEQ ID N° 1) was obtained. A recognition site for the TEV-protease in the 5 ′end was added. The full oligonucleotide sequence (TEV/rApS) was synthesized at Integrated DNA Technologies, Inc. (Iowa, U.S.A.) and cloned into a pSMART vector (Lucigen, Middletown, Wis.), generating the vector pSMARTTEVrApS.
Example 2
[0019] Generation of the Donor-gene Vector for Expression in E. coli: Using pSMART-TEV/rApS as a template, additional attB recombination sequences were flanked at the TEV/rApS ends using a double PCR amplification strategy. In the first step (pre-amplification), adapter-primers adpF (SEQ ID N° 2) and adpR (SEQ ID N° 3) were used to amplify a fragment of 147 bp. The PCR reaction was performed in a total volume of 50 μL containing 5 μL of Accuprime Pfx reaction mix 10× (Invitrogen, Carlsbad, Calif.), 1 μL of each primer (10 mM), 0.5 μL of AccuPrime Pfx DNA polymerase (2.5 U/μL; Invitrogen), 0.5 μL of pSMART-TEV/rApS (1:100 diluted) and 42 μL of H 2 O. The thermal profile was a starting denaturation step at 95° C. for 2 min, followed by 10 cycles of 94° C. for 15 s, 55° C. for 30 s and 68° C. for 135 s. A second round of PCR was performed on 10 μL of the pre-amplified product using the primers attB1 (SEQ ID N° 4) and attB2 (SEQ ID N° 5), resulting in the synthesis of a 181 by fragment (SEQ ID N° 6) ( FIG. 1 a ). The PCR reaction was performed in a total volume of 50 μL containing 5 μL of Accuprime Pfx reaction mix 10× (Invitrogen), 4 μL of each primer (10 μM), 0.5 μL of AccuPrime Pfx DNA polymerase (2.5 U/L; Invitrogen) and 26.5 μL of H 2 O. The applied thermal profile had a starting denaturation at 95° C. for 1 min, followed by 5 cycles of 94° C. for 15 s, 45° C. for 30 s and 68° C. for 125 s, and a final round of amplification consisting of 20 cycles of 94° C. for 15 s, 55° C. for 30 s and 68° C. for 135 s. The amplification products were electrophoretically resolved in a 1% agarose gel and stained with ethidium bromide. The amplified 181 by product was excised and purified using the Qiaexll Gel Extraction Kit (Qiagen, Germany) following the protocol described by the manufacturer. The obtained DNA was used for a “BP recombination” reaction with the entry vector pDONR207 (Invitrogen, U.S.A.) ( FIGS. 1 b and 1 c ). The BP Clonase Enzyme Mix (Invitrogen) was used for the reaction according to the manufacturer's protocol. The resulting entry vector (pDNOR207-TEV/rApS) ( FIG. 1 c ) was used for the transformation of chemically competent E. coli DH5α using standard procedures, and the recombinant clones were grown overnight in LB-agar plates supplemented with 25 mg/L gentamicin. Positive clones were confirmed by sequencing, by BsrGI enzyme restriction analysis resolved in an agarose gel, and with specific PCR reactions.
[0020] A Gateway™ LR recombination reaction was performed between pDNOR207-TEV/rApS and pDEST17 (Invitrogen, USA) ( FIGS. 1 d and 1 e ). For the reaction, LR Clonase Enzyme Mix (Invitrogen), Pstl-linearized pDNOR207-TEVrApS and pDEST17 vector were incubated according to the manufacturer's procedures. Then, 5 μL of the recombinant mixture was used for direct transformation of chemically competent E. coli BL21 (DE3) following standard procedures (Sambrook et al., 1989), and the transformed E. coli were grown overnight in LB-agar plates supplemented with carbenicillin, 100 mg/L. Primary positive clones were screened by PCR, and the final selected clone containing the pDEST17-pre-TEVrApS expression vector was confirmed by sequencing.
Example 3
[0021] Expression and Purification of AMP in E. coli BL21 (DE3): A clone of E. coli positive for expression vector pDEST17-pre-TEV/rApS, as verified by sequencing (Macrogen Inc., Korea), was used in induction experiments of the designed recombinant peptide. An aliquot of 5 mL of the selected clone of E. coli BL21 (DE3) was prepared by incubation in LB medium supplemented with carbenicillin, 50 mg/L. The clone was cultivated overnight at 26° C. under agitation at 180 rpm. Then, four aliquots of 1 mL each were incubated in 250 mL flasks containing the same culture medium and grown for an additional 9 h. Once the cultures reached OD 600 =1.8, isopropyl-b-d-thio-galactopyranoside (IPTG) was added to a concentration of 1 mM for peptide induction during an additional 3 h at four different temperatures (25° C., 26° C., 28° C., and 37° C.) and 180 rpm. The bacterial cultures were centrifuged at 12,000×g, and the supernatants were removed. The pellets were processed for peptide purification through Ni2+ charged columns using QIAexpress®Ni-NTA Fast Start (Qiagen) under denaturing conditions following the manufacturer's instructions. Four eluted fractions per culture were collected and quantified for protein content according to Bradford et al. (1976) using the Coomassie Plus (Bradford) Assay Kit (Pierce, Rockford, Ill., USA).
Example 4
[0022] Pre-TEV/rApS Digestion and rApS Purification: The protein-enriched fraction purified from the Ni2+ affinity column was subjected to TEV peptidase processing by incubation in 12.5 μL of 20× rTEV buffer, 2.5 μL of 0.1 M DTT, 5 μL of TEV protease, and 230 μL of water. The digestion was conducted by incubation overnight at 4° C. To obtain the rApS fraction from the digestion reaction, the mixture was re-purified using the Ni2+ column, with the first eluted fraction from the column containing the peptide. The protein was quantitatively determined as previously indicated.
Example 5
[0023] Mass Spectrometry Analysis of Purified pre-TEV/rApS and rApS: Re-purified samples of the peptides were automatically analyzed in an ABi4800 MALDI TOF/TOF mass spectrometer (Applied Biosystems, Framingham, Mass., USA) under positive ion reflector mode (ion acceleration voltage of 25 kV for MS acquisition and 1 kV for MSMS) or linear mode for peptides ≧4 kDa. The resulting spectra were stored in the ABi4000 Series Explorer Spot Set Manager. The MS and MSMS fragment ion spectra were smoothed and corrected to zero-baseline using routines embedded in the ABi4000 Series Explorer Software v3.6. External calibration was used to reach a typical mass measurement accuracy of <25 ppm.
Example 6
[0024] Recombinant Peptide Expression in Nicotiana tabacum:
[0025] a) Construction of input vector with pDONRP4-P1 R and pDONR221. The ankyrin promoter sequence was amplified with the primers attB4 (5′-GGGGACAACTTTGTATAGAAAAGTTGTC-NNN-3′) (SEQ ID N° 7) and attB1r (5′-GGGGACTGCTTTTTTGTACAAACTTGC-NNN-3′) (SEQ ID N° 8), and the rApS sequence was amplified with attB1 (5′-NNN3 GGGGACAAGTTTGTACAAAAAAGCAGGCTTC-3′) and attB2 (5′-GGGGACCACTTTGTACAAGAAAGCTGGGTC-NNN-3′), where NNN represents the specific nucleotide sequence. The following PCR conditions were used: 5 μL of Reaction Mix 10× AccuPrime Pfx (Invitrogen), 4 μL of each primer (10 mM each), 0.5 μL of AccuPrime Pfx DNA Polymerase (2.5 U/μL; Invitrogen), 0.5 μL of vine genomic DNA and 36 μL of ddH 2 O. The thermal profile was initial denaturation at 95° C. for 2 min, followed by 29 cycles with denaturation at 94° C. for 15 sec, annealing at 55° C. for 30 sec and extension at 68° C. for 2 min 15 sec. The results of the amplifications were visualized by electrophoresis on a 1% agarose gel with ethidium bromide staining (Sambrook et al., 1989). The bands corresponding to the expected size were cut and purified with Qiaexll Gel Extraction Kit (Qiagen, Germany) according to the manufacturer's instructions. The purified fragments of this reaction were used for recombination with the pDONRP4-P1 R and pDONR221 vectors (Invitrogen) with “BP Clonase” (Invitrogen) following the manufacturer's instructions. The vectors were cloned in E. coli DH5a grown in LB medium supplemented with 50 mg/L kanamycin.
[0026] b) Construction of expression vector with R4pGWB401. For the construction of the plant expression vector, the vectors pDONRP4-P1R-Ankyrin and pDONR221-rApS containing the regulatory and coding sequences, respectively, were recombined with vector R4pGWB401 (Nakagawa et al., 2009) using “LR Clonase” (Invitrogen). The resulting vector was cloned in E. coli DH5α grown in LB medium supplemented with 50 mg/L spectinomycin.
[0027] c) Construction of expression vector with pGWB502. For the construction of the plant expression vector, the pDONR207-TEV/rApS vector containing the chimeric gene and the target vector pGWB502 (Nakagawa et al., 2007) were recombined using “LR Clonase” (Invitrogen). The resulting vector was cloned in E. coli DH5α and grown in LB medium supplemented with 50 mg/L spectinomycin.
[0028] d) Transformation of tobacco: For obtaining genetically modified tobacco plants with the expression vector, the protocol of Sparkes et al. (2006) was used. Young leaves of approximately 4-6 weeks were infiltrated with a solution containing acetosyringone 1 M, sodium orthophosphate dodeca-hydrate (Na 3 PO 4 .12H 2 O) 2 mM, MES (2-[N-morpholin]-ethanesulfonic acid; Phytotechnology Labs) 50 mM, D-glucose 25 mM and A. tumefaciens 3101 (OD 600 =0.3) harboring the vector to evaluate the plant material. After 72 hours of infiltration, the leaves of the plant were removed, sterilized with a 10% solution of sodium hypochlorite, washed with sterile ddH 2 O and cut into square pieces of approximately 1 cm 2 . The fragments were cultured in Petri dishes containing 4.43 g/L germination medium (MS-S) of Murashige and Skoog (1962), supplemented with vitamins (Phytotechnology Labs, USA), 0.8% (w/v) agar TC (Phytotechnology Labs), 3.0% (w/v) sucrose (Phytotechnology Labs), 0.1 mg/L indole butyric acid (IBA, Sigma Aldrich, USA), 0.8 mg/L 6-benzylaminopurine (BAP; Sigma Aldrich), 200 mg/L carbenicillin (Sigma Aldrich), 200 mg/L timentin (Phytotechnology Labs) and 300 mg/L kanamycin (Phytotechnology Labs). The explants were maintained in MS-S to sprout, which occurred in approximately 3 weeks. Subsequently, the shoots were excised and cultured for two weeks in Petri dishes with 4.43 g/L rooting medium (MS-R) of Murashige and Skoog supplemented with vitamins, 0.8% (w/v) TC agar, 3.0% (w/v) sucrose, 0.5 mg/L indole butyric acid (IBA), 200 mg/L carbenicillin, 200 mg/L timentin and 300 mg/L kanamycin. Finally, regenerated plantlets were planted separately in flasks (150 mL) containing base MS medium (4.43 g/L of Murashige and Skoog supplemented with vitamins, 0.8% [w/v] national agar (Veronica Sepulveda, Chile) and 3.0% [w/v] sucrose). The plants were maintained in this medium until evaluation.
Example 7
[0029] Functionality Tests of Peptides Produced in Bacteria and Plants:
[0030] a) Evaluation of Peptides obtained in E coli: Isolates from Botrytis cinerea, Fusarium oxysporum, Trichoderma harzianum and Alternaria spp. were treated with the purified fractions of the digested and non-digested peptides (pre-TEV/rApS and rApS) derived from the selected recombinant clone of E. coli (Example 3).
[0031] The potential antifungal abilities of both peptides were evaluated by analysis of the growth patterns of these fungi on agar PDA (potato-dextrose) in Petri dishes supplemented with protein extracts at 500 μg/L (162 nM) and 250 μg/L (81 nM), respectively.
[0032] The control growth assays were performed on PDA dishes without peptides. The growth patterns were evaluated according the amount of time required for the fungi to reach the dish walls in the control plates (10 days after inoculation in darkness at room temperature). Structural images of the fungi hyphae patterns were obtained using a Olympus® microscope (Center Valley, Pa., USA), and spores were counted using a Neubauer camcorder (Brand®, Wertheim, Germany) at 40×. The data were subjected to analyses of variance, and averages were separated by the least significant difference test (LSD) at the 5% level of significance using Statgraphics Centurion XV (Manugistics Inc., Rockville, Md., USA). Petri dishes containing grown fungi were scanned and digitalized for statistical processing. The area of the mycelia was quantified using Gel-Pro Analyzer 4.0 (Media Cybernetics, Minneapolis, Minn., USA), and surface values in pixels were transferred to Excel (Microsoft Corporation, USA) for analysis. The average value of the colored haloes was calculated using scanned images of five repetitions on the tenth day after inoculation. The collected data were subjected to variance analysis, and the averages separated by LSD at the 5% level of significance. The confrontation results of the peptides are shown in tables 1 and 2. Table 1 shows the spore count. Table 2 shows the quantification of the area of the mycelium in pixels.
[0000]
TABLE 1
Spore count
Purified
Trichoderma
Fusarium
peptide
harzianum
Botrytis cinerea
Alternaria sp
oxysporum
fraction
average
DE
LSD
average
DE
LSD
average
DE
LSD
average
DE
LSD
rApS
5.0 × 10 6
1.0 × 10 5
a
1.02 × 10 6
2.31 × 10 5
A
0
0
a
7.6 × 10 5
8.98 × 10 4
a
Pre-
1.40 × 10 7
1.55 × 10 6
b
5.98 × 10 5
8.92 × 10 4
A
1.82 × 10 6
2.33 × 10 5
b
1.17 × 10 6
7.27 × 10 4
b
TEV/rApS
Control
2.14 × 10 7
1.57 × 10 6
c
9.17 × 10 6
4.93 × 10 5
B
3.15 × 10 6
9.29 × 10 4
c
1.76 × 10 6
1.31 × 10 5 ′
c
[0000]
TABLE 2
Petri
Central Area (pixels)
dish/agar
Trichoderma
Fusarium
PDA
harzianum
Botrytis cinerea
Alternaria sp
oxysporum
plus:
average
DE
LSD
average
DE
LSD
average
DE
LSD
average
DE
LSD
rApS
85718
12155
a
170781
69412
A
412403
14385
a
511699
55046
a
Pre-
623533
95785
b
235089
24328
A
430672
7665
a
498691
78927
a
TEV/rApS
Control
820412
42611
c
824804
53429
B
460848
18115
b
670810
98093
b
Example 8
[0033] Growth Inhibition Assays at Different Concentrations of Peptide rApS: The inoculation of 5 mL of LB was performed with 100 μL of bacteria ( Xanthomona campestris and Clavibacter michiganensis ), followed by overnight culturing. The absorbance was quantified at OD 600 . Once the Abs was quantified, dilutions were made to obtain an Abs to inoculate each tube with the same concentration of bacteria with an initial OD 600 of 0.04. Different peptide concentrations were used. Each tube was inoculated with an rApS peptide concentration, as shown in Tables 3 and 4. A final volume of 10 mL in a 50 mL tube was used. In addition, a control without peptide was used for each bacterium. The kinetics of the process was followed for 8 h from time zero, determining the Abs every 2 h. The sample was 1 mL, as shown in FIGS. 4 and 5 . The data were logarithmically transformed for the exponential phase of kinetics, and a linear regression was performed on the transformed data. The slope of the regression is the specific growth rate of the bacteria: p (h-1). The p (specific growth rate) was compared by LSD, and the data were interpreted, as shown in Tables 3 and 4.
[0000]
TABLE 3
Xanthomona campestris (G−)
Xanthomona campestris
Tube
μ (h −1 )
SD
LSD
Control
0.385
0.011
a
1 μg/L
0.371
0.011
a
10 μg/L
0.375
0.012
a
100 μg/L
0.386
0.007
a
1 mg/L
0.329
0.014
b
2 mg/L
−0.015
0.002
c
3 mg/L
−0.012
0.002
c
4 mg/L
−0.019
0.002
c
[0000]
TABLE 4
Clavibacter michiganensis (G+)
Clavibacter michiganensis
Tube
μ (h −1 )
SD
LSD
Control
0.072
0.011
a
1 μg/L
0.070
0.008
a
10 μg/L
0.069
0.010
a
100 μg/L
0.075
0.010
a
1 mg/L
0.069
0.006
a
2 mg/L
0.069
0.009
a
3 mg/L
0.073
0.009
a
4 mg/L
0.066
0.009
a
12.5 mg/L
0.009
0.001
b
15.5 mg/L
0.003
0.0003
b
[0034] b) Evaluation of the rAp-S produced in Nicotiana tabacum
[0035] For the evaluation of the rAp-S produced in Nicotiana tabacum, total protein was extracted from 14 transgenic lines, and 30 μg of total protein from each plant was spread on a Petri plate containing PDA. Each plate was inoculated with a suspension of 2.0×10 9 spores of T. harzianum as the growth inhibition indicator. After 7 d, the growth inhibition was determined visually, and no biological or statistical analysis was performed if there was any plaque inhibition. The three top lines that generated some degree of growth inhibition were selected, and a further test was performed with 60, 90 and 120 μg of total protein in the same plate. The plate was divided into four equal areas, and in each area, a Whatman paper disk was placed on the edge with the required peptide amount or a water control. All peptide amounts (60, 90 and 120 μg) were added to a volume of 100 μL to ensure that the experiment was more homogeneous. Each plate was inoculated with a spore suspension of 2.0×10 9 of T. harzianum in the center. After 3 days, the inhibition area was determined with the program Pro Analyzer Gel using the disk peptide areas where the fungus did not grow ( FIG. 6 ). The areas of inhibition, in pixels, of the transgenic lines (TL) of Nicotiana tabacum (Nt) were determined: TL Nt 9, TL Nt 12, TL Nt 15 and Control Nt (untransformed). Each line, including the Control Nt, was analyzed separately. In the LSD analysis, the different amounts of total protein (60, 90, and 120 μg and water) were compared. The Control Nt and water controls for each TL Nt showed no inhibition of T. harzianum (Table 5).
[0000]
TABLE 5
Total protein extracts from tobacco.
Inhibition Area of Trichoderma harzianum (pixels)
Petri
Control Nt
LT Nt 9
LT Nt 12
LT Nt 15
Dish
Average.
SD
LSD
Average
SD
LSD
Average
SD
LSD
Average
SD
LSD
water
*
*
**
*
*
**
*
*
**
*
*
**
60 μg
*
*
**
221.67
0.47
a
3416.5
94.5
a
1048.67
26.4
a
90 μg
*
*
**
516
108
b
3340
37
a
1930.5
36.5
b
120 μg
*
*
**
605
169.41
b
4185.5
271.5
b
2741
20
c
Inhibition of T. harzianum with total protein extracts from transgenic lines (LT) of Nicotiana tabacum (Nt) at increasing amounts (60, 90 and 120 μg) and a water control. The Control Nt was a non-transgenic plant.
*No inhibition;
**No statistical analysis.
[0036] These experimental examples were exemplifying and not limiting. Although the yields obtained and the activity of the recombinant peptide were successful in their objective of producing rAp-S active against economically relevant pathogens using bacteria and plants as sources of expression, the present invention does not exclude the potential use of this chimeric gene to express the said AMP in additional expression systems, such as yeast. The use of a medium/large scale of such peptides is desirable for the control of plant pests.
[0037] Optionally and as a non-limiting method, the methodology to be used for the implementation of the total protein extract of N. tabacum can be performed together with a suitable carrier.
[0038] Protein extraction was performed with a basic extraction buffer consisting of 1 M sodium chloride, 0.1 M sodium acetate, 1% PVP, 10 mM β-mercaptoethanol, 0.25% v/v Triton X-100, and 20% glycerol. This total extract can be diluted to the required concentration in ddH 2 O (pH between 4 and 5) and sprayed onto the plants. The plants can also be treated using alternative means.
[0039] The extracts of total protein from E. coli were prepared from the method described in Example 3 and then diluted in ddH 2 O (pH between 4 and 5) to the concentration required for spraying.
[0040] These preparations are suitable for the direct application to crops, plants, plant parts, roots and/or soil that is healthy or infested with fungi and/or phytopathogenic bacteria.
[0041] After obtaining the protein extracts from both E. coli and N. tabacum, a lyophilization step can be incorporated, which gives stability to the extract and allows storage at room temperature. Additionally, this step will facilitate the commercialization of the product.
[0042] In short, if the extract is obtained by synthesis in E. coli, the process is scaled to high volume bioreactors, ball or disc grinder, continuous or cake centrifuge, extract stripper column and a final lyophilizer to process this volume.
[0043] In the case that the process selected for obtaining the extract uses N. tabacum, an extension of cropland that allows the required demand to be met, ball grinder, continuous or cake centrifuge and a lyophilizer able to process the final high volume should be considered. | A chimeric nucleotide sequence is provided encoding peptides with antimicrobial activity to be expressed in plants, plant cells or transformed plant material that will produce the peptide sequences derived from SEQ ID No. 1 and SEQ ID No. 6. A method is also provided for conferring resistance or tolerance to plant pathogenic fungi or bacteria on a plant using suitable transfer vectors, which contain the coding sequence for the peptides with antimicrobial activity. | 2 |
BACKGROUND OF THE INVENTION
[0001] Children are cared for and provided medical treatment, including surgery, in medical care facilities such as hospitals and surgery centers. Stays in such facilities can be intimidating and cause much apprehension in young patients, despite the best efforts of a caring staff. Such apprehension can be the result of unfamiliar surroundings and equipment as well as unfamiliar ways of doing things and sometimes painful medical treatments. Further, unhappiness can result simply from being not being able to move freely about the facility.
[0002] During stays in treatment facilities, children are oftentimes immobile either because they are attached to medical devices like intravenous injection devices (I.V.'s), or their illness. The assisted movement of the child about the facility can help eliminate the feeling of immobility to make the child happier. However, the staff is generally not available for taking children for trips simply for fun. When a parent is visiting, they could move the child around to provide fun and mobility. To date though, the transport devices have presented obstacles for parents, generally the same obstacles the staff encounters when they transport the child for treatment. As discussed more in detail below, there are typically two transport devices used in care facilities, wheelchairs and wagons. Many children cannot be transported in wheelchairs because they cannot sit upright either because of age or illness. Further, the transport of an infusion pump, the preferred I.V. for children, on a wheel chair is difficult and poses safety concerns when attached to a pole attached to the wheelchair. If the I.V. is not attached to the wheelchair, two or more people would be required to move the child, wheelchair and I.V. around and two people may not be available when needed. In addition, a ride in a wheelchair is not generally viewed by a child as much fun. Wagons have been used instead of wheelchairs to provide an environment of fun for the child. Even though wagons can be effectively used to transport children who cannot sit upright and provide added fun by alleviating the feeling of immobility, they too have posed problems, such as safety and user convenience, as discussed below.
[0003] Children will also require movement about the facility by the staff to provide medical treatment. The children will realize or soon learn that a trip with staff within the facility usually results in a treatment which many times is unpleasant. Oftentimes, the contemplation of a treatment is worse than the treatment itself. Many of these children have little understanding of the treatments they will receive or the purpose of the treatment, except in the most general terms, adding to the anxiety and apprehension of being in an unfamiliar environment. The facility's staff works to reduce the apprehension and anxiety through the use of many mechanisms Such mechanisms include providing an atmosphere of fun to distract a child from thinking about what may occur particularly at the end of a trip in the facility. A ride in a wagon can provide such an atmosphere of fun.
[0004] During movement about, children will oftentimes be required to travel while connected to an I.V. or other medical device. Being connected to such a medical device also makes a child immobile unless they are being helped. Drip type I.V. bags have not been preferred for use with children since the flow rate can be easily changed by the child and they are not very accurate in flow rate at the lower flow rates of medicine used for children both of which create safety concerns. Typically, children are connected to an infusion pump for intravenous injection to more accurately regulate the injection of medicines or the like than can be accomplished with the drip type I.V. bags and because infusion pumps are relatively tamper resistant. Even though infusion pumps are preferred, they are typically large and heavy, presenting safety concerns should one fall on a child if not properly secured.
[0005] As discussed above, movement of a child about a care facility is typically accomplished using a wheelchair or a wagon. The use of a wheelchair presents problems. Wheelchairs may require two staff members, one to push while another staff member walks along with the I.V. on a wheeled pole. The use of wheelchairs and attendance by two staff members can be intimidating and cause additional apprehension in children. Devices have been provided to attach the I.V. device to the wheelchair to allow operation of the wheelchair by only one staff member. Although providing an improvement in efficiency such an arrangement can still cause apprehension and present safety and convenience issues. Because of the size and weight of an infusion pump, they are difficult to mount to a wheelchair. They either project over the seat area and patient or outwardly past the wheels. Projecting over the seat area makes entry, exit and sitting difficult. This position of the infusion pump also provides a safety concern since the device is positioned over the upper body of the child and should the device fall, a major injury could result. When projecting out over the wheels, there is a risk it will hit something or cause an empty chair to tip. Further, many children do not have the capacity to be upright in a wheel chair for various reasons, e.g., they may be too young or may not have sufficient muscle strength to sit upright making the use of a wheel chair not acceptable for such children. If a wheeled dolly is used to help support the pole and prevent wheelchair tipping, it too may hit an object causing damage. The wheels are also noisy and many times do not properly steer both of which can cause apprehension and make operation difficult. More importantly, the dolly wheels may catch causing the I.V. device to fall which in turn may painfully pull out the catheters and cause excessive bleeding.
[0006] Recently, wagons have been used for transport to provide a fun environment and allow children who cannot sit upright to be transported, but present their own problems. One such wagon is disclosed in U.S. Pat. No. 5,292,094. The wagon has a bracket for attaching an I.V. pole with a wheeled dolly attached to its bottom for rolling on the floor. The pole is attached to the side of the wagon adjacent a rear wheel with a clamp and two bolts. The dolly rests on the floor to provide vertical support for the pole and medical device(s) thereon. The problems with the use of a wheeled dolly are discussed above. For transport, a child is placed in the wagon and their I. V. pole and platform are then secured to the wagon via a clamp and bolt arrangement. Such an attachment is cumbersome and time consuming, potentially adding to the child's apprehension. At the end of the trip, the pole must also be similarly released from the wagon by loosening the two bolts, all potentially additionally adding to the apprehension of the child. Such a bolt arrangement for attachment creates safety issues since the bolts may become loose during transport. Further, the pole is located on one side of the wagon between the front and rear wheels making that side essentially inaccessible for entry and exit and for tending to the passenger. Further, by being located near the rear of the wagon, the I.V. device is positioned over the upper body of the child when the child is riding face forward. Should the I.V. become loose and fall, a major injury may be incurred by the child. With a bolt on attachment of the I.V. pole, should it become loose and free of attachment to the wagon (or wheel chair) there is a risk that the I.V. catheters will be pulled out of the child causing great pain and excessive bleeding. The wagon of the '094 patent is a single pivot front axle type wagon. During sharp turns, such wagons can be unstable since the front support points (front wheels) move toward the center of gravity of the wagon narrowing the front wheel support width. When the front wheels are in a sharp turn position, the wagon is also unstable at rest increasing the probability it will tip and thereby create more apprehension in the child being transported.
[0007] Another wagon of the above general type has an I.V. pole permanently mounted to the wagon on the rear end and outboard of the perimeter of the wagon bed and wheels. By being rear mounted, the center of gravity of the wagon and attachments is more rearward on the wagon. When a pulling force is applied to the wagon's handle, the front of the wagon has a tendency to lift more because of additional weight of the pole and whatever device is attached thereto creating apprehension in the passenger as well as raising safety concerns. Also, by being rear mounted, the I.V. device is positioned above the upper body of a forward facing child presenting the safety concerns discussed above.
[0008] Although the above discussion was directed to I.V. devices, it is pointed out that other medical devices may also need to be moved with the child compounding the problems discussed in reference to I.V. devices. Such devices include portable gas supplies like oxygen tanks and tube feeders for liquid diet foods.
[0009] It is believed important for safety, effective treatment and comfort of a child, that their apprehension be kept as low as possible. The elimination unhappiness and of sources of potential apprehension is thus important. As discussed above, sources of unhappiness and apprehension include immobility, the type of vehicle used for transport, the inability to quickly and easily ready the child and I.V. for transport and departure from the vehicle and the stability of the vehicle. Whether a staff member or a family member is using the wheelchair or wagon for transport, the problems encountered are generally the same.
SUMMARY OF THE INVENTION
[0010] Among the several objects and features of the present invention may be noted the provision of a transport device that will create an atmosphere of fun when used by a child; the provision of such a device that is easy and quick to attach an I.V. pole to; the provision of such a device that is easy and quick to remove an I.V. pole from; the provision of such a device that provides room on both sides of the device for assisting the entry and exit of a child; the provision of such a device that is stable in operation and at rest; the provision of such a device that is stable during movement and when at rest regardless of the positions of its guiding wheels; the provision of such a device that is safe and convenient for child and medical device transport; and the provision of such a device that is economical to manufacture.
[0011] The present invention involves the provision of a wagon for transporting a person in a medical care facility. The wagon includes a wagon body having an upwardly facing support surface and an upstanding guardrail extending around a substantial portion of the support surface. The body has a front end and a rear end and opposite sides forming a wagon body perimeter. A handle is connected to the wagon body at the front end for applying a pulling force to the wagon body. Wheels are rotatably mounted on the body with a pair of the wheels positioned adjacent the front end and a pair of the wheels positioned adjacent the rear end with a substantial portion of the support surface being positioned between outermost portions of the front and rear wheels. The wagon body, guardrail, handle and wheels form a wagon. A pole with a top end and a bottom end is provided.
[0012] A pole mount is secured to the wagon and is adapted for mounting the pole on the wagon. The wagon provides substantially the entirety of support for the pole. The pole mount is positioned inboard of said wagon body perimeter and the pole has a substantial portion thereof positioned inboard of the wagon body perimeter.
[0013] A further aspect of the present invention is the provision of a wagon for use in transporting children in a medical care facility who require equipment or intravenous fluid during transport. The wagon comprises a body sized and shaped for receiving a child, the body having a front end, a rear end, sides and a floor for supporting the child. Wheels are located generally at the front and rear ends of the body and mounted on the body for rolling support of the body on a surface. An elongate handle is connected to the body generally at the front end thereof and extending forwardly for pulling the wagon. A pole is supported by the wagon and has a support portion extending over the wagon floor. The support portion is adapted for mounting medical equipment and/or intravenous fluid containers thereon whereby the equipment and containers are disposed at least partially over the wagon floor to increase stability of the wagon when pulled along the surface by the handle.
[0014] Other objects and features will be in part apparent and in part pointed out hereinafter.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] [0015]FIG. 1 is a perspective of a wagon for use in transporting a child in a medical care facility;
[0016] [0016]FIG. 2 is an enlarged fragmentary perspective of a right front corner of the wagon showing a mount for an I.V. pole;
[0017] [0017]FIG. 3 is an enlarged section taken along the line 3 - 3 in, FIG. 2 and shows a lower portion of an I.V. pole;
[0018] [0018]FIG. 4 is a bottom of the wagon showing the I.V. pole in a stowed position; and
[0019] [0019]FIG. 5 is an enlarged fragmentary perspective of the right front corner of the wagon viewed from the interior of the wagon.
[0020] Corresponding reference characters indicate corresponding parts throughout the several views of the drawings.
DETAILED DESCRIPTION
[0021] As seen in FIG. 1, a transport device is provided which is preferably in the form of a wagon designated generally by the numeral 10 . The wagon 10 includes a bed 15 which has an upwardly facing child support surface (or “floor”) 17 . The bed 15 includes opposite side edges 18 , 19 , a front end edge 20 and rear end edge 21 . The edges 18 - 21 form an outer perimeter for the bed 15 . The bed 15 also includes a downwardly facing bottom panel 25 forming a portion of an undercarriage 26 (FIG. 4).
[0022] The wagon 10 is provided with front and rear wheel arrangements 28 , 30 adjacent the front 32 and rear 34 of the wagon 10 respectively (see FIGS. 1 and 4). Preferably, the front wheel arrangement 28 includes two wheels 36 , 37 and the rear wheel arrangement 30 also includes two wheels 38 , 39 . The wheels 36 , 37 are spaced apart across the width of the wagon 10 with each being positioned adjacent a respective front corner 40 , 41 of the wagon. The wheels 38 , 39 are spaced apart across the width of the wagon 10 with each being positioned adjacent a respective rear corner 42 , 43 of the wagon. The rear wheels 38 , 39 are rotatably mounted on an axle 45 that is secured to the wagon 10 via brackets 47 depending from the bottom panel 25 . Preferably, the brackets 47 are integral with the bed 15 and are laterally spaced apart. The wheels 38 , 39 are mounted to the axle 45 by press nuts 49 . The brackets 47 , bottom surface 25 and the axle 45 define an opening 51 therebetween.
[0023] The front wheels 36 , 37 are mounted to the wagon 10 preferably for independent pivoting movement whereby they individually pivot about offset vertical axes and remain adjacent their respective corner 40 , 41 even during sharp turns. As shown in FIGS. 1 and 4, the front wheels 36 , 37 are each rotatably mounted on its own axle bracket 54 . The axle brackets 54 are of the self pivoting type, i.e., they turn when a force is applied to the wagon 10 similar to the operation of the front wheels on a grocery cart. As shown, the axle bracket 54 includes a generally vertical pivot pin 55 pivotally mounted to the bed 15 and retained in a bearing 56 via a support shoulder 58 and a swaged head 60 . An arm 62 extends from the pivot pin 55 to an axle 64 . Preferably the pivot pin 55 , arm 62 and axle 64 are an integral structure formed from a metal rod. The arm 62 depends from the pivot pin 55 and inclines downwardly and backwardly from the pivot pin 55 whereby the axle 64 is behind or in a trailing position relative to the pivot pin 55 (and also relative to the direction of wagon movement). When the wagon 10 moves in response to a motive force such as by pulling a tongue or handle 68 , the axle 64 will assume the trailing position and be generally perpendicular to the pulling force. The front wheels 36 , 37 will follow but, unlike the wagons using a single front axle with a center pivot, remain adjacent their respective front corner 40 , 41 to maintain the wagon 10 stable during movement and at rest regardless of front wheel orientation.
[0024] The wheels 36 - 39 form a wagon 10 support perimeter WP that remains substantially the same regardless of the pivotal orientation of the front wheels 36 , 37 . The wheel support perimeter WP is defined by the outermost ground contact areas of the wheels 36 - 39 (as shown by the dashed lines of FIG. 4). Further, at least a majority of the bed 15 , both laterally and transversely, is inboard of the wheel support perimeter.
[0025] The wagon 10 is provided with a guardrail or rack designated generally as 75 (see FIG. 1). The guardrail 75 comprises a pair of side rails 77 , a front rail 78 and a rear rail 79 . The guardrail 75 can be partly or totally removably mounted on the bed 15 or can be permanently attached to the bed. Preferably, the rails 77 - 79 are separate parts from the bed 15 for facilitating manufacture of the wagon 10 . After manufacture of the various parts, they are assembled to form the wagon. The rails 77 - 79 have posts (not shown) that fit into sockets (not shown) in the bed 15 for mounting the rails to the bed. The side rails 77 may additionally be mounted to the front and rear rails 78 , 79 by posts (not shown) in sockets (not shown) as at the junctions 76 . The guardrail 75 is upstanding and substantially completely surrounds the bed 15 and is inboard of the bed perimeter and preferably the side or longitudinal portions of the wheel perimeter WP. Alternatively, the side rails 77 could be hingedly mounted to the bed 15 such that they could be dropped down, without removal, to facilitate entry into and exit from the wagon 10 . The guard rail 75 and bed 15 form a passenger compartment 80 with an upwardly opening top 81 .
[0026] The wagon 10 is provided with the handle 68 . The handle 68 is pivotally attached to the front of the wagon 10 by a pivot pin 82 extending thru hitch brackets 83 . The handle 68 includes a shank 84 extending from the pivot pin 82 terminating in a D-shaped grip 85 . The grip 85 is adapted to be grasped by a person to provide motive force to the wagon 10 . Preferably, the pivot pin 82 permits movement of the handle 68 about a generally horizontal axis and in a generally vertical plane. The handle 68 will not pivot substantially laterally relative to the bed 15 . To effect steering of the wagon 10 , a lateral or sideways force is applied to the handle 68 .
[0027] It is preferred that the bed 15 , guard rail 75 , handle 68 and wheels 36 - 39 be made of polymeric material. The use of polymeric material facilitates cleaning and disinfecting. Preferably these components are of molded construction, e.g., by rotational molding, leaving a hollow core for weight and material reduction while maintaining strength. A preferred wagon is a Trail Blazer model 2200 available from Radio Flyer, Inc. of Chicago, Ill. The wagon 10 is adapted for mounting an I.V. pole 90 to the wagon 10 (see FIGS. 2, 3 and 5 ). Preferably, the pole 90 is removably mounted to the wagon 10 . As best seen in FIGS. 2 and 3, a socket (broadly “mount”) 92 is secured to the guard rail 75 at a front corner 40 of the wagon 10 . Preferably, the socket 92 extends through a generally vertical bore 93 in the front rail 78 and a second generally vertical through hole 94 thru the bed 15 . The socket 92 is positioned between walls 96 A, 96 B and the outside surfaces 96 C, 96 D of the front rail 78 . A fastener 95 , such as a hex nut is secured to the bottom end of the socket 92 . The upper end of the socket 92 has a laterally extending flange 97 engaged with a top surface 99 of the front rail 78 . The socket 92 captures the front rail 78 and bed 15 between the fastener 95 and flange 97 for securement to the wagon 10 . The socket 92 includes a thru bore 100 with a generally vertically oriented longitudinal axis.
[0028] The pole 90 with opposite lower and upper ends 104 , 105 is provided for supporting a medical device, e.g., a liquid storage and injection device such as an infusion pump 101 (FIG. 1) or I.V. The lower end 104 is received in the bore 100 of the socket 92 . A stop collar 106 (see FIG. 5) is secured to the pole 90 adjacent the lower end 104 and engages the flange 97 to limit the axial movement of the pole into the bore 100 and to provide vertical support for the pole. A generally L-shaped finger 108 extends outwardly and then downwardly from the collar 106 forming a channel 109 between the finger and the pole. A portion of the front rail 78 is received in the channel 109 and thereby prevents rotation of the pole 90 in the socket 92 and fixes the rotational position of the pole 90 .
[0029] The pole 90 is mounted in a manner to not destabilize the wagon 10 and to provide easy entry into and exit from the wagon. Further, the wagon 10 substantially entirely supports and in the illustrated embodiment, entirely supports the pole 90 and devices mounted thereon. As seen in FIGS. 1 and 5, a substantial portion of the pole 90 is inboard of the outside perimeter of the bed 15 and the side or longitudinal portions of the wheel perimeter WP and is positioned above the bed 15 . The pole 90 is bent at 110 adjacent the lower end 104 and above the collar 106 . The orientation of the finger 108 relative to the bend 110 is such that the upper portion 105 of the pole 90 is positioned inboard of the guard rail 75 and the wheels 36 - 39 thus positioning the center of gravity of the pole and the I..V. bag when connected to a hook 114 secured to the upper end 105 also inboard of the bed perimeter, guardrail 75 and the wheel perimeter. Any medical device, such as an infusion pump, gas supply, tube feeder, etc., mounted on the pole will also be over the wagon bed inboard of the bed perimeter, guardrail 75 and the wheel perimeter. Such devices will also be positioned over the lower body portion of the child and not over the upper body portion of the child when positioned in a forwardly facing orientation. If an I.V. drip type bag is used, it will be out of easy reach of the child reducing the chance of tampering. The pole 90 and medical device are easily mounted on the wagon 10 and are easily removed from the wagon when it and the transported child reach their destination. Only one staff member is required to move the wagon, attached medical device(s) and patient thru the facility.
[0030] The wagon 10 is able to stow the pole 90 on the wagon when the pole is not in use. Preferably, the pole is stowed in a position that will not present itself as a danger to personnel and equipment during moving and storage of the wagon 10 and its length is such that a substantial portion and preferably its entirety is within the wagon bed perimeter. As seen in FIG. 4, the pole 90 is removably mounted to the undercarriage of the wagon 10 . The lower end 104 of the pole 90 is received over the axle 45 with the axle being positioned within the channel 109 formed by L-shaped finger 108 and the pole. The lower end 104 is thus removably retained on the rear axle 45 . Means is also provided on the underside of the wagon 10 to releasably retain the upper end 105 of the pole 90 . The retention means includes a spring action clip 126 which may be made of stainless steel. The clip 126 utilized two arcuate fingers 127 , 128 forming a pole receiving area (not shown) approximately equal to the diameter of the pole 90 . The opening 129 adjacent the free ends of and between the fingers is smaller than the diameter of the pole 90 whereby the pole is releasably retained between the fingers of the clip 126 . The clip 126 is secured to the bottom panel 25 of the undercarriage of the wagon 10 . The pole 90 is stowed for carriage by forcing the pole between the fingers into the enlarged area between the fingers and released from its stowed position under the wagon by simply pulling the pole out from between the fingers.
[0031] The above described wagon 10 is well adapted for use in a medical facility for transporting children to make moving about more fun and thereby reduce apprehension. The wagon requires only one staff member to operate. It also allows for easy entry into and exit from thereby making the trip more enjoyable and also less apprehensive. The pole 90 and its mount also provide for the easy mounting and removal of medical devices and can be conveniently stowed under the wagon out of the way when not in use. The wagon is also stable in operation because of the front wheel configuration and the mounting of the pole.
[0032] When introducing elements of the present invention or the preferred embodiment(s) thereof, the articles “a”, “an”, “the” and “said” are intended to mean that there are one or more of the elements. The terms “comprising”, “including” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements.
[0033] In view of the above, it will be seen that the several objects of the invention are achieved and other advantageous results attained.
[0034] As various changes could be made in the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense. | A device for transporting children in a medical care facility is provided. The device includes a wagon carrying a pole inboard of the wheels. The pole is received in a holder whereby the wagon solely carries and supports the pole. The wagon includes a guard rail surrounding a wagon bed forming a passenger compartment with an upwardly opening top. The front wheels are independently pivotable for steering and stabilizing the wagon. | 0 |
BACKGROUND OF THE INVENTION
The present invention relates to the field of electric personal care product, and more specifically relates to a kind of double-blade hair trimming device.
At present, a hair trimming device comprises a foil in the middle and trimming blades on the two sides. The disadvantage is that after using the trimming blade, it is difficult for a user to align the hair with the meshes of the foil and put the hair through. The user needs to move back and forth repeatedly in order to finish trimming by the foil. Yet, during the reciprocating movement, the trimming blade may trim away the hair that the user may like to keep. In the case of armpit hair-trimming, the trimming blades may cut the skin when using the foil.
There is another type of hair trimming device, wherein a razor is added onto the trimming device. The razor can be hidden, so in this case the trimming device can be used alone. Alternatively, the razor can be extended. The longer hair can first be trimmed by the trimming device disposed in the front position. After that, the razor disposed in the back position can be used to shave. Another option is that the razor can be extended fully such that it can be used directly. The disadvantage is that this combination of blade heads is difficult to control. One needs to manage the use angles of the trimming device and the razor at the same time. The user may worry that the razor may cut the skin and affect the trimming effects, especially on the sensitive area.
BRIEF SUMMARY OF THE INVENTION
In view of the aforesaid disadvantages now present in the prior art, the present invention provides a kind of double-blade trimming device which is safer to use.
The present invention adopts the following technical proposal:
A double-blade hair trimming device which comprises a blade body, a blade head, and a driving device disposed inside the blade body, wherein the blade head comprises a thick blade unit and a thin blade unit which are disposed side by side.
The thick blade unit is a thick blade assembly, whereas the thin blade unit is a thin blade assembly. The thick blade assembly and the thin blade assembly are disposed in the same direction. The thin blade assembly is disposed rear to the thick blade assembly.
The thick blade assembly comprises a thick fixed blade and a first movable blade. The thin blade assembly comprises a thin fixed blade and a second movable blade. The thick fixed blade, the first movable blade, the thin fixed blade and the second movable blade each has an edge which is provided with a teeth section. The first movable blade is sleeved within an inner side of thick fixed blade, and the teeth sections thereof overlap with each other correspondingly. The first movable blade moves reciprocally corresponding to the thick fixed blade; when the teeth sections of the first movable blade and the thick fixed blade engage with each other, a thick blade trimming surface is formed without any gaps therebetween. The second movable blade is sleeved within an inner side of thin fixed blade, and the teeth sections thereof overlap with each other correspondingly. The second movable blade moves reciprocally corresponding to the thin fixed blade; when the teeth sections of the second movable blade and the thin fixed blade engage with each other, a thin blade trimming surface is formed without any gaps therebetween. The thick blade trimming surface and the thin blade trimming surface are disposed side by side and face the same direction. The thin fixed blade has a tooth thickness of less than 0.1 mm.
The teeth section of the thick fixed blade comprises serrated openings which are evenly arranged on an edge thereof along a lengthwise direction. The teeth section of the first movable blade comprises a plurality of teeth which are evenly arranged on an edge thereof along a lengthwise direction, wherein each of the teeth has a V-shaped pointing end, a V-shaped cross section, and two edges which are both disposed with blades. The teeth section of the thin fixed blade comprises a plurality of teeth which are evenly arranged along an edge thereof along a lengthwise direction, wherein each of the teeth has a V-shaped pointing end and two edges which are both disposed with blades. The teeth section of the second movable blade comprises a plurality of teeth which are evenly arranged along an edge thereof along a lengthwise direction, wherein each of the teeth has a V-shaped pointing end and two edges which are both disposed with blades.
The blade head also comprises a blade head protection line which is disposed between the teeth of the thick fixed blade and the thin fixed blade, and is parallel to the thick blade trimming surface and the thin blade trimming surface. Specifically, it is disposed at a front end of the thin fixed blade. When the present invention is in use, the thick blade assembly is first used to shave the skin, then the blade head protection line will stretch the skin which has been shaved by the thick blade assembly. Afterwards, the thin blade assembly is used to shave.
The blade head protection line is an independent component, or a protrusion on a surface of the thick fixed blade, or an elongated component of the blade head protection cover which is parallel to both the thick blade trimming surface and the thin blade trimming surface.
The blade head comprises a blade head cover case which is used to accommodate the thick blade assembly and the thin blade assembly.
The blade head comprises a blade head protection cover which is engaged with the blade head cover case. The blade head protection cover has a side edge which is provided with a row of openings corresponding to shape, density and size of spacing of the teeth of the thick fixed blade, forming a guiding groove which facilitates entry of hair between the teeth of the first movable blade.
The teeth of the thick fixed blade are engaged with an end of the row of openings of the blade head protection cover. The teeth of the first movable blade are concealed within a cavity formed by the engagement of the teeth of the thick fixed blade and the row of openings.
The thick blade unit is a thick blade teeth edge, whereas the thin blade assembly is a thin blade teeth edge. The thick blade teeth edge and the thin blade teeth edge are reversely disposed.
The blade head comprises a fixed blade and a movable blade. Axes of the fixed blade and the movable blade overlap. The fixed blade and the movable blade are each provided with teeth sections at two opposite edges thereof. The fixed blade is sleeved within an inner side of the movable blade. The teeth sections of the fixed blade and the movable blade overlap with each other correspondingly. The movable blade moves reciprocally corresponding to the fixed blade to trim away hair. One of the edges of the fixed blade is relatively thicker than the edge opposite thereto. The thicker edge of the fixed blade overlaps with one of the edges of the movable blade to form the thick blade teeth edge. The thinner edge of the fixed blade overlaps with the other edge of the movable blade to form the thin blade teeth edge. Inner sides of the teeth sections of the fixed blade of the thick blade teeth edge and the thin blade teeth edge are engaged with outer sides of the teeth sections of the movable blade of the thick blade teeth edge and the thin blade teeth edge without any gaps to form trimming surfaces for hair trimming. The teeth section of the thinner edge of the fixed blade has a tooth thickness of less than 0.1 mm.
The teeth section of the thicker edge of the fixed blade comprises serrated openings which are evenly arranged along a lengthwise direction of that edge. The teeth section of the thinner edge of the fixed blade comprises a plurality of teeth which are evenly arranged along a lengthwise direction of that edge, wherein each of the teeth has a V-shaped pointing end and two edges which are both disposed with blades.
The teeth sections of the two edges of the movable blade each comprises a plurality of teeth which are evenly arranged along a lengthwise direction of the edge; each of the teeth has a V-shaped pointing end, a V-shaped cross section, and two edges which are both disposed with blades.
The blade head also comprises a blade head protection line which is disposed at a side of thin blade teeth edge which is far away from the thick blade teeth edge. It is parallel to both the thin blade teeth edge and the thick blade teeth edge and is located on the same plane as an outer surface of the fixed blade.
The blade head protection line is an independent component, with its two ends fixed onto a case of a double-sided double-blade hair trimming device.
The blade head protection line can also be an elongated protrusion on a surface of a case of a double-sided double-blade hair trimming device which is parallel to both the thick blade teeth edge and the thin blade teeth edge.
Compared with the prior art, the present invention has the following advantages:
When carrying out a first shave with the double-sided double-blade hair trimming device of the present invention, the thick blade teeth edge can remove the thick and long hair. After that, by shaving in a reverse way, the remaining short and fine hair will be removed by the thin blade teeth edge. The length of the hair of the skin being shaved can be less than 0.1 mm, thus attaining the effect of a razor. The blade head protection line can stretch and flatten the skin which has been shaved by the thick blade teeth edge, hence the rough area of the skin will not be scratched by the thin blade assembly during shaving. Also, the present invention is suitable for shaving twice in opposite directions. This allows the user to shave away all thick and long hair during the first shave, and keep the hair he likes during the second shave. The present invention is simple in structure and convenient to use.
The single-sided double-blade hair trimming device of the present invention is disposed with a thick blade assembly and a thin blade assembly at the same trimming direction. Thick and long hair can be removed by the thick blade assembly by only one shave without the need for accurate alignment, and the remaining short and fine hair can be removed by the thin blade assembly. The length of the hair of the skin being shaved can be less than 0.1 mm. The blade head protection line can stretch and flatten the skin which has been shaved by the thick blade assembly, hence the rough area of the skin will not be scratched by the thin blade assembly during shaving.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates a sectional view of the overall structure of the present invention according to Embodiment 1;
FIG. 2 illustrates a structural schematic view of the exposed blade head of FIG. 1 excluding the blade head cover case;
FIG. 3 illustrates a structural schematic view of the blade head of FIG. 2 including the blade cover case;
FIG. 4 illustrates an exploded schematic view of the blade head of FIG. 1 ;
FIG. 5 illustrates a schematic view of the overall structure of the present invention according to Embodiment 2;
FIG. 6 illustrates a structural schematic view of the fixed blade;
FIG. 7 illustrates a structural schematic view of the movable blade.
FIG. 8 illustrates an alternative configuration of the protection line according to Embodiment 2 of the present invention, wherein the protection line is shown is an elongated protrusion on a surface of the double-blade hair trimmimng device.
FIG. 9 is the same as FIG. 8 , but shown in another perspective view.
FIG. 10 is an enlarged view of the blade head shown in FIG. 8 .
DETAILED DESCRIPTION OF THE INVENTION
Embodiment 1
As illustrated in FIGS. 1 to 4 , the single-sided double-blade hair trimming device of the present invention comprises a top case 1 and a bottom case 2 which are engaged with each other to form a case. It further comprises a switch 5 , a battery 3 , a motor 4 and a double eccentric shaft 6 which are disposed inside the case and are connected in sequence from a rear end to a front end of the case. Two shaft ends of the double eccentric shaft 6 are respectively connected to a thin blade rocker arm 7 and a thick blade rocker arm 8 . The thin blade rocker arm 7 and the thick blade rocker arm are connected to a blade head 9 , wherein the switch 5 , the battery 3 and the motor 4 are connected by circuits. The front end of the bottom case 2 is provided with a blade head cover case 29 .
The blade head 9 comprises a thick blade assembly 91 and a thin blade assembly 92 which are disposed side by side and in the same direction. The thick blade assembly 91 comprises a first movable blade holder 11 , a first movable blade 12 and a thick fixed blade 13 . The thin blade assembly 92 comprises a second movable blade holder 14 , a second blade 15 and a thin fixed blade 16 . The lengths of the first movable blade holder 11 and the first movable blade 12 are shorter than the length of the thick fixed blade 13 , whereas the lengths of the second movable blade holder 14 and the second movable blade 15 are shorter than the length of the thin fixed blade 16 .
The thick fixed blade 13 , the first movable blade 12 , the thin fixed blade 16 and the second movable blade 15 each has an edge which is provided with a teeth section. The first movable blade 12 is sleeved within an inner side of the thick fixed blade 13 , and the teeth sections thereof overlap with each other correspondingly. The first movable blade 12 moves reciprocally corresponding to the thick fixed blade 13 ; when the teeth sections thereof engage with each other, a thick blade trimming surface 21 is formed without any gaps therebetween. The second movable blade 15 is sleeved within an inner side of the thin fixed blade 16 , and the teeth sections thereof overlap with each other correspondingly. The second movable blade 15 moves reciprocally corresponding to the thin fixed blade 16 ; when the teeth sections thereof engage with each other, a thin blade trimming surface 31 is formed without any gaps therebetween. The thick blade trimming surface 21 and the thin blade trimming surface 31 are disposed side by side and face the same direction.
The teeth section of the thick fixed blade 13 comprises serrated openings which are evenly arranged on an edge thereof along a lengthwise direction. The teeth section of the first movable blade 12 comprises a plurality of teeth which are evenly arranged on an edge thereof along a lengthwise direction; each of the teeth has a V-shaped pointing end, a V-shaped cross section, and two edges which are both disposed with blades. The teeth section of the thin fixed blade 16 comprises a plurality of teeth which are evenly arranged on an edge thereof along a lengthwise direction; each of the teeth has a V-shaped pointing end and two edges which are both disposed with blades. The teeth section of the second movable blade 15 comprises a plurality of teeth which are evenly arranged on an edge thereof along a lengthwise direction; each of the teeth has a V-shaped pointing end and two edges which are both disposed with blades.
The first movable blade holder 11 has a top side which is disposed with two protrusions 111 for clamping an end of the thick blade rocker arm 8 , so as to fix the first movable blade holder 11 with the thick blade rocker arm 8 . The top side and a bottom side of the first movable blade holder 11 are each disposed with two cylindrical positioning protrusions 112 at two ends thereof. The first movable blade 12 is disposed with two mounting holes 121 which fit with the two positioning protrusions 112 of the bottom side of the first movable blade holder 11 . The first movable blade holder 11 and the first movable blade 12 are fixed with each other by engaging the two positioning protrusions 112 with the mounting holes 121 . Two springs 33 are provided, with one end of each pressing against the blade head cover case 29 and the other end of each sleeved within each of the two positioning protrusions 112 disposed on the top side of the first movable blade holder 11 ; the first movable blade 12 is pressed by pressing the first movable blade holder 11 . Two ends of the thick fixed blade 13 are each disposed with a screw hole 131 . The thick fixed blade 13 is mounted on the blade head cover case 29 by engaging the blade locking screws 44 and the blade locking nuts 55 . Specifically, the blade locking nuts 55 are first securely mounted into the blade head cover case 29 ; the thick fixed blade 13 is then placed thereon, and lastly the blade locking screws 44 are mounted. The first movable blade 12 and the first movable blade holder 11 are disposed between the thick fixed blade 13 and the blade head cover case 29 . The teeth of the first movable blade 12 and the thick fixed blade 13 face the same direction.
The blade head 9 also comprises a blade head protection cover 18 , which is engaged with the blade head cover case 29 . The blade head protection cover 18 has a side edge which is provided with a row of openings 181 corresponding to density and size of the teeth of the thick fixed blade 13 . The teeth of the thick fixed blade 13 are engaged with an end of the row of openings 181 . The teeth of the first movable blade 12 are concealed within a cavity formed by the engagement of the teeth of the thick fixed blade 13 and the row of openings 181 .
The second movable blade holder 14 has a top side which is disposed with two protrusions 141 for clamping an end of the thin blade rocker arm 7 , so as to fix the second movable blade holder 14 and the thin blade rocker arm 7 . The top side and a bottom side of the second movable blade holder 14 are each disposed with two cylindrical positioning protrusions 142 at two ends thereof. The second movable blade 15 comprises two mounting holes 151 which fit with the two positioning protrusions 142 of the bottom side of the second movable blade holder 14 . The second movable blade holder 14 and the second movable blade 15 are fixed with each other by engaging the two positioning protrusions 142 with the mounting holes 151 . Two springs 33 are provided, with one end of each pressing against the blade head cover case 29 and the other end of each sleeved within each of the two positioning protrusions 142 disposed on the top side of the second movable blade holder; the second movable blade 15 is pressed by pressing the second movable blade holder 14 . Two ends of the thin fixed blade 16 are each disposed with a screw hole 161 . The thin fixed blade 16 is mounted on the blade head cover case 29 by engaging the blade locking screws 44 and the blade locking nuts 55 . Specifically, the blade locking nuts 55 are first securely mounted into the blade head cover case 29 ; the thin fixed blade 16 is then placed thereon, and lastly the blade locking screws 44 are mounted. The second movable blade 15 and the second movable blade holder 14 are disposed between the thin fixed blade 16 and the blade head cover case 29 . The teeth of the second movable blade 15 and the thin fixed blade 16 face the same direction.
The blade head 9 also comprises a blade head protection line 17 which is disposed between the thick fixed blade 13 and the thin fixed blade 16 , and is parallel to the edges of the thick fixed blade 13 and the thin fixed blade 16 which are disposed with teeth sections, wherein the two ends thereof are fixed onto an inner side surface of the blade head cover case 29 so as to stretch the skin which has been shaved by the first movable blade 12 , thereby preventing the skin from bulging and being cut by the second movable blade 15 .
The blade head protection line 17 can be an elongated component of the blade head cover case 29 which is disposed between the thick blade assembly 91 and the thin blade assembly 92 .
The blade head protection line can be a wall-like elongated protrusion protruded from a surface of the thick fixed blade 13 .
The thick fixed blade 13 forms a certain angle with the thin fixed blade 16 , or the two are on the same plane.
The teeth of thin fixed blade 16 are ultrathin with a thickness of less than 0.1 mm, preferably 0.07 mm.
The teeth of thick fixed blade 13 can be separated from the end of the row of openings 181 of the blade head protection cover 18 , and thus leaving a gap therebetween. This allows the hair inside the blade head cover case 29 to be washed away from the gap.
Embodiment 2
As illustrated in FIGS. 5 to 7 , the double-sided double-blade trimming device of the present embodiment comprises a blade body 20 and a blade head 10 . The blade body 20 is disposed with a driving device therein. The blade head 10 comprises a thick blade teeth edge 110 and a thin blade teeth edge 120 .
Specifically, the blade head 10 comprises a fixed blade 30 and a movable blade 40 . Axes of the fixed blade 30 and the movable blade 40 overlap. The fixed blade 30 and the movable blade 40 are each provided with teeth sections 310 , 320 , 410 , 420 at two opposite edges thereof. The fixed blade 30 is sleeved within an inner side of the movable blade 40 . The teeth sections 310 , 410 of the fixed blade 30 and the movable blade 40 overlap with each other correspondingly; the teeth sections 320 , 420 overlap with each other correspondingly. The movable blade 40 moves reciprocally corresponding to the fixed blade 30 to trim away the hair. One of the edges of the fixed blade 30 is relatively thicker than the edge opposite thereto. One of the edges of the movable blade 40 is relatively thicker than the edge opposite thereto. The thicker edge of the fixed blade 30 overlaps with one of the edges of the movable blade 40 to form the thick blade teeth edge 110 . The thinner edge of the fixed blade 30 overlaps with the other edge of the movable blade 40 to form the thin blade teeth edge 120 . Inner sides of the teeth sections 310 , 320 of the fixed blade of the fixed blade teeth edge 110 and the thin blade teeth edge 120 are engaged with outer sides of the teeth sections 410 , 420 of the movable blade without any gaps to form trimming surfaces for hair trimming.
The teeth section 310 of the thicker edge of the fixed blade 30 comprises serrated openings which are evenly arranged along a lengthwise direction of that edge. The teeth section 320 of the thinner edge of the fixed blade 30 comprises a plurality of teeth which are evenly arranged along a lengthwise direction of that edge; each of the teeth has a V-shaped pointing end, and two edges which are both disposed with blades.
The teeth section 410 of the thicker edge of the movable blade 40 comprises a plurality of teeth which are evenly arranged along a lengthwise direction of that edge; each of the teeth has a V-shaped pointing end, a V-shaped cross section, and two edges which are both disposed with blades. The teeth section 420 of the thinner edge of the movable blade 40 comprises a plurality of teeth which are evenly arranged along a lengthwise direction of that edge; each of the teeth has a V-shaped pointing end and two edges which are both disposed with blades.
The blade head 10 also comprises a blade head protection line 130 which is disposed at a side of the thin blade teeth edge 120 which is far away from the thick blade teeth edge 110 .
The blade head protection line 130 is an independent component, with its two ends fixed onto a case of the double-sided double-blade hair trimming device.
The blade head protection line 130 can also be an elongated protrusion on a surface of the case of the double-sided double-blade hair trimming device. It is parallel to both the thick blade teeth edge 110 and the thin blade teeth edge 120 .
The teeth section 320 of the thinner edge of the fixed blade 30 has a tooth thickness of less than 0.1 mm.
The tooth thickness of the teeth sections of the two opposite edges of the movable blade 40 can be the same. After trimming, the length of the hair is determined by the tooth thickness of the teeth section of the fixed blade 30 , therefore the present embodiment does not set limits to the relative thickness and absolute thickness of the teeth sections of the two opposite edges of the movable blade 40 .
The above embodiments described in greater detail are only a few embodiments of the present invention and should not limit the scope of the present invention. To any person skilled in this field of art, any change and modification without deviating from the concept of the present invention should also fall within the scope of protection of the present invention. The scope of protection of the present invention should be limited by the Claims. | A double-blade hair trimming device having a trimmer handle, a blade head, and a driving device disposed inside the trimmer handle. The device has both a thick blade unit used for trimming hard, thick and long hair, and a thin blade unit used for trimming short and fine hair. Hair on the skin can be tidily trimmed by just one shave or one shave in each of two opposite directions. The length of the hair after shaving is less than 0.1 mm. | 1 |
BACKGROUND OF THE INVENTION
The invention relates to a method of placing a web on an entrenchment below the ground water level. Usual methods of placing such a web consist of first draining the entrenchment at the start of a constriction project so that the web can be placed in a simple way. Draining the water does however also affect the ground water level in the area outside the entrenchment and therefore, draining is not always allowed at the beginning of a constrication project. A typical example is an entrenchment for a road near a wildlife habitat.
SUMMARY OF THE INVENTION
The invention provides a solution for the above problem. According to the invention, the solution is achieved by wrapping the web around a core or roll, floating the core or roll in either the entrenchment or a water course which is connected with the entrenchment, and subsequently navigating the wrapped-up core or roll to the beginning of the entrenchment, after which unwinding and attachment of the web takes place.
Such a web is preferably formed by connecting lengths of web material segments, cut off at size substantially parallel to the center line of the core or roll, to preceding lengths of web material segments. The web segments can be connected by welding or adhering.
The length of the core should substantially be equal to the resultant width of the entrenchment. If a road is concerned which has to be processed in this way, it is determined according to the invention, that the resultant width of the entrenchment is realized by enlarging the projected width by applying at least one flood verge.
Unwinding takes place after the core is positioned by pumping water from the entrenchment at the location where the web still has to be applied, to the location between the initial edge of the web and the core. During this pumping, a braking moment and braking force is preferably exerted on the core.
In order to apply the method according to the invention also a number of installations is necessary. The floating core is for instance formed so for that purpose, that, while being pivotal about its own axis by means of moment arms, it is connected to at least one pontoon, the pontoon being provided with winches to bring the core in the correct position.
Furthermore means are necessary to lower compression means with the aid of guide cables to secure the web edges, provided with ring eyes, to structure parts, positioned under water. For this purpose, the guide cables extend between screw eyes, present in a concrete clamping edge, to for instance auxiliary scaffolds or one or more derrick barges, dependent upon the nature of the intermediary structures. Preferably, barbed bars are provided between the guide cables and screw eyes.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be further elucidated hereinafter on the basis of the drawings, in which by way of example an embodiment is shown of an installation to apply the method according to the invention. In the drawings:
FIG. 1 an abridged cross-section of an entrenchment having some installations at the left adapted to be used when applying the method according to the invention, and having at the right an entrenchment profile with a flood verge under the water level, all this substantially according to the line I--I of FIG. 2;
FIG. 2 shows a schematic plan view of the installations of FIG. 1;
FIG. 3 shows a longitudinal section of an entrenchment at the location of a part of a structure protruding above the water, to elucidate the beginning of the web placing process;
FIG. 4 shows details of the guide means of FIG. 3; and
FIG. 5 shows a longitudinal section of an entrenchment at the location of a structure which does not protrude above the water level, on the basis of which the end of the web placing process is elucidated.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In FIGS. 1 and 2, the equipment at the left includes a working floor 1 having a length which is equal to the resultant width of a web which is wound on a reel 2. The resultant width of the web may be, for example, 175 meters. Along the working floor 1, a core 3 can be moored, on which the web is wound. This is effected by winding the complete web V, necessary for one section, i.e., a part of the entrenchment between for instance two structures, including a triangle as a consequence of a possible oblique crossing of one of the structure parts, and the prefabricated web edges. It goes without saying that the entrenchment need not be rectangular in plan view, but may have any shape.
The drum is moored as closely as possible against the working floor, and the working floor may be over a slope 4. The drum 3 can comprise a steel tube having a diameter of approximately 1 meter and a wall thickness of approximately 12.5 millimeters. On the other hand, the web is very thin (up to a magnitude of 1 millimeter) by which only an increase in radius of some tens of centimeters is developed around the drum 3 for an entrenchment of approximately 400 meters. The working floor 1 can be located in the vicinity of the bank of the section to be dredged or a small channel which communicates with said section to be dredged.
The drum 3 is connected to two small pontoons 7 via two moment arms, which are connected to the drum via a hydromotor 6. This additional structure causes the total width of the roll with pertaining parts to be approximately 2 meters larger than the length of the core or roll itself. Winches 8 are provided on the pontoons, and the winches 8 are controllable both with respect to their tensile force and holding force. With the aid of the winches 8, the core or roll can be introduced into and maintained in any position within the dredged section.
The initial and final operations when placing the web at the beginning and end of the entrenchment are most simple, as the web needs not be arranged under water in these situations. However, the situation at the location of the structures K is completely different, such as structures which protrude above the water surface P, as in FIG. 3, and structures which do not protrude above the water surface P, as in FIG. 5.
In the event the structure K obliquely intersects the entrenchment, the drum 3 can be manoeuvered to the extreme corner point of the respective section, and then the partly unwound point can be drawn onto an auxiliary scaffold 10 (FIG. 3), secured to a viaduct 9, and temporarily anchored. By further unwinding the roll and navigating it parallel to the viaduct 9, the total web edge can be brought onto the auxiliary scaffold 10. One will note then, that the complete triangle is between the roll and the viaduct in a folded manner, which, however, presents no disadvantage.
Before the roll or core 3 is navigated against the viaduct 9, spaced apart vertical guide cables 11 are prearranged from screw eyes 13 (FIGS. 3 and 4) located in a concrete clamping edge 12, to the auxiliary scaffold 10 to be arranged. The vertical guide cables 11 can be spaced approximately 3 meters apart from one another. The guide cables 11 are laced through ring eyes (not shown) present in the web edge. Furthermore the web edge is provided with some ballast, with the aid of which the web edge can be lowered along the guide cables.
A barbed bar 14 is placed between the guide cables 11 and the concrete clamping edge 12 (FIG. 4) which should prevent the web, when passed over the barbed bar 14 from sliding back. With sensors one can determine whether the web edge is in the required position and if not, it can be brought into the required position.
Before the clamping construction 15, weighing about 1 ton, can be arranged, it has to be certain that on its track laong the guide wires 11 it does not meet the web V, as this will undoubtedly cause damage. In FIG. 3 two clamping constructions 15 are visible. One clamping construction 15 is on an already provided clamping edge 12 of the structure K. The other clamping construction 15 is shown closer to the water surface P, and this latter clamping construction will be arranged next to the first one. Securing the clamping constructions 15 next to each other takes place by turning nuts 23 (FIG. 4) over the screw eyes 13. The guarantee that the web will not be damaged by the clamping constructions can be achieved by further turning the core or roll in a position perpendicular to the axis of the entrenchment, keep them under control, and then introducing a slight difference in water pressure by means of pumping over water. This exerts a pressure on the web, the pressure being indicated by arrows A in FIG. 3. Care should be taken, however, that the water that flows to create this pressure causes the least disturbance possible, and that is the reason that, for instance, a long spray pipe 34 must be sued for spraying a water spray 35 towards the web.
After having checked first whether the web does indeed leave the clamping edge 12 almost horizontally, the clamping units 15, which have a length of approximately 6 meters, can be payed out one by one from the auxiliary scaffold 10 along the guides wires 11 and screwed on with the aid of divers.
The web V can now be further payed out under a certain braking moment and braking force by pumping-over water, while care is furthermore taken that the core or roll will not become clamped against one of the banks.
It has to be remarked that a leak flow around the core heads or roll heads has an erosive effect. Therefore a light erosion protection of 0.1 meters of gravel on the slope is necessary. Furthermore one should realize that the resultant length may be approximately 5 meters longer than the projected one, which requires the provision of a flood verge, indicated at the right in FIG. 1 by means of a dashed line 16. It is also possible to solve this problem by including a fold on the core or roll.
In order to ensure that the web edge does not disappear under water, it is advisable to fix it with for instance pegs 17 (FIG. 1), which can then be connected by wires 22 to a ring eye (not shown), which is included in the reinforced web edge.
In a later stage the web edge has to be brought above the water and the flood verge has to be completed. This can be done by locally withdrawing the web edge from the opposite side of the section of the entrenchment and thereby enabling re-profiling the verge.
The connection of the web at the ends of the respective sections of the entrenchment takes place in a similar manner as described for the connection at the beginning at the location of a structure K.
A difference is, however, that a water enclosure 18 (FIG. 5) is introduced between the web and the bottom, i.e., under the fold, which can, however, be discharged by creating an overpressure relative to the ground water.
In order to ensure that the fold will be on the bottom, a sausage-like ballast or weight 32, which is connected at one side to the guide wires 11, can be lowered parallel to the axis of the entrenchment to create the above-mentioned overpressure so that the water in the water enclosure 18 is discharged.
The connection to the structure 19 (FIG. 5), which does not extend through the water level, is additionally complicated, so that one has to work from the water with a derrick barge 20. The guide wires 11 can then be tensioned by means of somewhat more robust floats 21.
Although the invention is elucidated hereabove on the basis of an application to an entrenchment for a road for automobile traffic in which the entrenchment is, in fact, required to be drained at some time in the future after the web has been laid, it is remarked that the invention method and the pertaining installations can also be used in situations where no draining at any point in time is permitted since no influence of the ground water level in the direct neighborhood is permissible. In this respect one may think of large closed reservoirs, like rubbish tips, water basins, swimming pools and the like reservoirs. | A method and apparatus for laying a web in a submerged condition on an entrenchment floor includes wrapping a web onto a drum as said drum is floating on a water surface of the entrenchment, navigating the wrapped drum to a beginning section of the entrenchment, and unwinding the drum as it is floating on the entrenchment while further navigating the drum. Water is pumped from a section of the entrenchment already layed with the web, thus imparting an unwinding force to the drum and giving the web a convex shape along the portion of the web which extends from the drum to the entrenchment floor. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of co-pending U.S. application Ser. No. 13/470,761, filed May 14, 2012, and claims priority to JP 2011-157000, filed Jul. 15, 2011, and JP 2012-048124, filed Mar. 5, 2012.
TECHNICAL FIELD
[0002] The present invention relates to an implant fixture typically used in the field of dentistry, especially in the field of artificial tooth roots.
BACKGROUND OF INVENTION
[0003] In the recent years, public attention has been paid to implant technology by which an implant fixture such as an artificial tooth root is implanted in a living organism, thereby restoring a lost function.
[0004] In the field of dentistry, for example, a fossa for implantation of an artificial tooth root is formed with a drill or the like in a predetermined size in a jawbone after cutting open the gingiva of a tooth lost portion. An implant fixture is placed into the fossa. Then, a certain period of time is allowed for the surface of the implant fixture to integrate or fuse with the contacting surface of the jawbone at a micro level. This is called osseointegration. Following that, a superstructure or an upper structure (a crown) is mounted on the implant fixture directly or via an abutment.
[0005] In circumstances, specifically in the mouth, where a dental implant fixture is used, dental caries bacteria adhere to the tooth surface together with plaque and produce an organic acid such as lactic acid from carbohydrate or sugar, thereby decalcifying the tooth structure. The dental implant fixture is used in special circumstances where the implant fixture is exposed to an acid enough to cause decalcification of the tooth structure, compared with other prostheses such as artificial bones and joints. Thus, the dental implant fixture is required to have especially high durability, specifically high lactic acid resistance. In addition to the high durability, high performance in osseointegration, strength, and safety is called for.
[0006] Dental implant fixtures made from ceramics mainly composed of zirconia have been attracting public attention in the recent years (refer to JP 2002-362972 A). The ceramic implant fixtures are excellent in strength. Further, compared to metallic implant fixtures, ceramic implant fixtures are excellent in safety since they do not cause allergic reactions to metal.
[0007] Conventional ceramic implant fixtures have hardly attained both high durability and good osseointegration. Conventionally, surface finishing or surface treatment to provide appropriate surface roughness is required to improve osseointegration. For example, a titanium implant fixture needs surface finishing by sandblasting, acid treatment or both. If a ceramic implant fixture is subjected to such surface finishing, monoclinic crystalline structure is exposed on the surface of the implant fixture, thereby reducing the durability of the implant fixture.
[0008] If the ceramic implant fixture is not subjected to such surface finishing and the surface roughness is accordingly inappropriate, the degree of osseointegration is decreased.
[0009] In view of the above-mentioned technical problems, the present invention has been made. Accordingly, an object of the present invention is to provide an implant fixture having high durability and capable of excellent osseointegration.
SUMMARY OF THE INVENTION
[0010] An implant fixture of the present invention is made from ceramics containing zirconia, and has monoclinic percentage or percentage of monoclinic crystals of 1 volume % or less. The implant fixture comprises a buried portion having an arithmetic average roughness Ra of 1 to 5 μm.
[0011] The implant fixture of the present invention is excellent in resistance against lactic acid or the like since the monoclinic crystals or monoclinic crystalline structure accounts for 1 volume % or less, preferably 0.5 volume % or less, and more preferably 0 volume % of the total volume of the fixture.
[0012] The buried portion of the implant fixture has an arithmetic average roughness Ra in the range of 1 to 5 μm. This assures robust osseointegration between the bone and the fixture. Preferably, the maximum height Rz of the profile of the implant fixture is in the range of 5 to 40 μm.
[0013] Further, the implant fixture of the present invention has high affinity and remarkable compatibility with a living body (high bioaffinity and remarkable biocompatibility). Based on clinical testing, the implant fixture of the present invention evidently shows a significant difference with other implant fixtures.
[0014] According to the present invention, the zirconia content accounts for 86 mass % or more, preferably 89 mass % or more, and more preferably 92 mass % or more of the total mass of the implant fixture. If the zirconia content falls within this range, the resistance against lactic acid or the like may further be increased.
[0015] Preferably, the implant fixture contains alumina. As a result, dense ceramics may be obtained even with a low burning temperature. If alumina is not contained in the ceramics, dense ceramics may be obtained with a high burning temperature, but the sintered grain size of the ceramics becomes large. If the burning temperature is lowered, the sintered grain size becomes small, but ceramic density decreases. The alumina content is preferably in the range of 0.05 to 3 mass %, more preferably 0.05 to 1 mass %, and further preferably 0.05 to 0.1 mass % of the total mass of the implant fixture.
[0016] The implant fixture of the present invention preferably contains at least one sort selected from the group of yttria, ceria, magnesia, and calcia. Especially, it is preferable that the implant fixture contains yttria. Inclusion of one or more of these components may stabilize the contained zirconia in a tetragonal state. This, in turn, may suppress the surface of the implant fixture from crystallizing in the monoclinic system, thereby readily obtaining an implant fixture with low monoclinic percentage. This may also suppress crystallizing in the monoclinic system under the circumstances where the implant fixture is exposed to lactic acid and hot water, thereby increasing the durability of the implant fixture. If yttria is contained, its content is preferably in the range of 2 to 4 mol %.
[0017] The implant fixture preferably has a sintered grain size of 0.45 μm or less, more preferably 0.3 μm or less, and further preferably 0.009 to 0.3 μm. In this range of the sintered grain size, the resistance against lactic acid or the like may furthermore be increased. The sintered grain size is measured by planimetric method.
[0018] The implant fixture may contain minor components other than zirconia, alumina, yttria, ceria, magnesia, and calcia.
[0019] The ceramics forming the implant fixture are preferably dense, which may increase the resistance against lactic acid or the like and attain sufficient strength. The relative density of the ceramics is preferably 95% or more, more preferably 98% or more, and further preferably 99% or more.
[0020] Preferably, the implant fixture of the present invention has a surface that is substantially not subjected to annealing treatment. The term “annealing treatment” used herein means that sintered ceramics are subjected to heating with a high temperature of 800° C. or more after being subjected to cutting, polishing, blasting or other working. The annealing treatment reduces monoclinic crystals occurring on the worked surface of the sintered ceramics, but likely worsens the durability compared to a non-worked sintered surface.
[0021] The implant fixture of the present invention is typically manufactured by the following steps. In short, a slurry of ceramics containing zirconia is poured into a mold for the implant fixture and then the ceramics are let hardened.
[0022] According to the above-mentioned method, there is no need of cutting the shape of the implant fixture out of the sintered ceramics in a lump form. The monoclinic percentage hardly increases in the implant fixture. As a result, the manufactured implant fixture may have high durability.
[0023] In this manufacturing method, the surface roughness of the implant fixture may be determined by setting the surface roughness of an inner surface of the mold that contacts the slurry to a predetermined value.
[0024] For example, the surface roughness of the inner surface of the mold may be determined by blasting the inner surface of the mold. Alternatively, the surface of a master model is subjected to blasting and then the surface roughness of the master model is transferred to the inner surface of the mold. Sandblast media used in blasting have an average grain size of 50 to 500 μm, preferably 80 to 300 μm.
[0025] The blast media may be based on alumina, silicon carbide, and zirconia. The blast media typically include steel shot, steel grit, microshot, peening shot, SB ultra-hard shot, advanced shot, bright shot, stainless shot, aluminum cut wire, AMO beads, glass beads, glass powder, Alundum, carborundum, ceramic beads, nylon shot, polycarbonate, melamine, urea, walnut shot, apricot, and peach. Selection from these media is arbitrary. Sandblasters such as general suction sandblasters, general direct pressure sandblasters, small-sized recirculating sandblasters, barrel-type small-sized recirculating sandblasters, and pen-type sandblasters are available. A pen-type sandblaster may preferably be used in detailed blasting.
[0026] A typical blast pressure is 0.2 to 1.2 Kgf/cm 2 , depending upon the material and grain size of the blast media used.
[0027] A slurry used in the above-mentioned manufacturing method contains, for example, ceramic powder and binders for hardening the slurry. The slurry may also contain a water soluble polymer for viscosity adjustment, various solvents, and surface active agents for ready dispersion and wetting.
[0028] The binders used herein typically includes thermosetting binders such as epoxy resin, polyester, phenol resin, melamine resin, polyimide, cyanate ester resin, diallyl phthalate resin, silicone resin, isocyanate resin, and modified resins of these resins. Emulsions of these resins may alternatively be used. Further, thermal-gelation binders such as protein and starch may be used.
[0029] A solvent for the slurry is, for example, water, aromatic solvent, aliphatic solvent, ester, or ketone-based solvent. The slurry may be prepared by mixing the ceramic powder, binder and other components in the solvent, sufficiently dispersing and kneading them using a ball mill, and then performing vacuum defoaming.
[0030] The mold used in the above-mentioned manufacturing method is preferably made of elastically deformable and stretchable material. Thus, the mold may be deformed according to the shape, even a complex shape, of the implant fixture, thereby enabling the implant fixture to be readily taken out of the mold. The material of the mold typically includes wax, foamed polystyrene, natural rubber, styrene-butadiene rubber, nitrile-butadiene rubber, chloroprene rubber, ethylene-propylene rubber, silicone rubber, urethane rubber, fluororubber, phenol resin, and epoxy resin.
[0031] The implant fixture of the present invention is applicable as an artificial tooth root for dental purposes and is also applicable as an artificial bone in the fields of orthopedic surgery, plastic surgery, and oral surgery.
DESCRIPTION OF THE DRAWINGS
[0032] These and other objects and many of the attendant advantages of the present invention will readily be appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings.
[0033] FIG. 1 is an illustration used to explain the shape of an implant fixture of the present invention.
[0034] FIG. 2 is an illustration used to explain a manufacturing method of a mold.
[0035] FIG. 3 is a perspective view showing a configuration of the mold.
DETAILED DESCRIPTION OF THE INVENTION
[0036] Now, an embodiment of the present invention will be described below in detail with reference to the accompanying drawings.
1. Manufacturing of Implant Fixture
[0037] (1) Fabrication of Master Model
[0038] SUS (steel use stainless) material is worked into a shape of a publicly known implant fixture. This is used as a master model. The size of the master model is determined by multiplying the size of a finished implant fixture by a predetermined coefficient of more than one. This is because the ceramics are shrunk during burning process as described later. The predetermined coefficient differs depending upon the composition of ceramics slurry used. In this embodiment, the coefficient is preferably 1.3.
[0039] Next, the surface of the master model is subjected to blasting. The surface roughness (arithmetic average roughness Ra and maximum height Rz) of the blasted master model is determined such that a buried portion of the finished implant fixture may have surface roughness, specifically, an arithmetic average roughness Ra of 1 to 5 μm and maximum height Rz of 5 to 40 μm. The arithmetic average roughness Ra and maximum height Rz are specified in the “JIS B0601” (2001 edition).
[0040] In the Ra range of 1 to 5 μm, good osseointegration may be obtained. Especially, if Ra is in the range of 1 to 5 μm and Rz is in the range of 5 to 40 μm, osseointegration may furthermore be improved.
[0041] The surface roughness of the master model that falls within the above-identified range may readily be determined by manufacturing several sorts of implant fixtures having different surface roughness corresponding to varied surface roughness of the master model, and understanding the interrelationship of surface roughness between the master model and finished implant fixture. The arithmetic average roughness Ra and maximum height Rz of the master model may be determined to be as approximately 1.3 times large as those of the finished implant fixture as described earlier.
[0042] FIG. 1 illustrates the shape of an implant fixture, namely, the master model. The implant fixture 1 has a bar shape as a whole. The implant fixture 1 comprises a buried portion 1 a that is to be buried in a living organism and an exposed portion 1 b that is exposed out of the living organism and is mounted with a superstructure (not illustrated). The buried portion 1 a has a bar shape, more specifically, a cylindrical shape whose diameter becomes smaller toward the tip thereof. A nut portion 3 having a hexagonal section is formed on an outer surface of the buried portion 1 a in the vicinity of an upper end of the buried portion 1 a. The buried portion 1 a is screwed into the living organism by engaging a wrench or spanner with the nut portion 3 and turning the buried portion 1 a. A thread pair 9 and a groove 11 are formed in the outer surface of the buried portion 1 a except for the nut portion 3 . Specifically, the thread pair 9 is spirally formed on the outer surface of the buried portion 1 a. The thread pair 9 includes a first thread 13 and a second thread 15 disposed in parallel with a given interval therebetween. The groove 11 is defined as sandwiched between the first and second threads 13 , 15 .
[0043] (2) Fabrication of Mold
[0044] With reference to FIGS. 2 and 3 , how to fabricate a mold is described below. As illustrated in FIG. 2 , the master model 21 fabricated as described in the above-mentioned (1) is placed on a pedestal 23 having a wider horizontal surface than the master model 21 . In FIG. 2 , the shape of the master model 21 is simplified. Next, an outer model 25 having a hollow cylindrical shape with open ends (top and bottom) is mounted around the master model 21 and the pedestal 23 to receive the master model 21 and the pedestal 23 therein. An outer surface 23 a of the pedestal 23 is in close contact with an inner surface of the outer model 25 with no gap therebetween.
[0045] Next, liquid silicone rubber to be hardened as triggered by reaction is put into the outer model 25 . After 24 hours passes since the liquid rubber has been put into the outer model 25 , the mold 27 of the hardened silicone rubber is pulled out of the outer model 25 (see FIG. 2 ). The mold 27 has a concave portion 27 a corresponding to an inverted master model 21 in shape. Since the mold 27 is made of an elastic and stretchable material, it can readily be deformed and stretched.
[0046] (3) Preparation of Ceramics Slurry
[0047] A ceramic slurry is prepared by mixing the following components:
Ceramics powder: 100 parts by mass Water: 30 parts by mass Ester resin emulsion (methyl acrylate): 9 parts by mass Ester based solvent (butyl carbitol acetate): 3 parts by mass Ammonia water: To be appropriately added such that the pH of the ceramics slurry may be 9 to 10.
[0053] “TZ-3Y-E” (trade name) made by Tosoh Corporation is used as the ceramics powder. “TZ-3Y-E” is mainly composed of zirconia of 93 to 94.9 mass %. It also contains yttria of 4.95 to 5.35 mass % and alumina of 0.15 to 0.35 mass %.
[0054] (4) Manufacturing of Implant Fixture
[0055] The slurry prepared in the above-mentioned (3) is poured into the concave portion 27 a of the mold 27 fabricated in the above-mentioned (2). Then, the mold 27 is heated at 70° C. to harden the slurry. The hardened slurry (not-yet-burned ceramics) is pulled out of the mold 27 and is left for 24 hours at ordinary temperature for drying.
[0056] Then, the not-yet-burned ceramics are burned at 1300° C. to finish an implant fixture. If the burning temperature exceeds 1400° C., the sintered grain size of the zirconia contained in the implant fixture becomes larger or too large in some cases, thereby reducing the durability of the implant fixture. As a result, the implant fixture is likely to deteriorate due to water, lactic acid, or the like.
2. Evaluation of Finished Implant Fixture
[0057] The denseness, monoclinic percentage (percentage of monoclinic crystals), surface roughness, and sintered grain size of the finished implant fixture, which was manufactured by the manufacturing method as describe above, were evaluated. The results are as follows:
Denseness: Relative density of 99% or more Monoclinic percentage: 0 volume % Sintered grain size: 0.15 μm Arithmetic average roughness Ra: 1 to 5 μm Maximum height Rz: 5 to 40 μm
[0063] The denseness was evaluated by measuring bulk density as specified in JIS R1634 and dividing the value of measured bulk density by theoretical density. The monoclinic percentage was evaluated by X-ray analysis. The sintered grain size was evaluated by planimetric method.
[0064] The planimetric method is described below in detail. The sintered surface or mirror polished surface of the ceramics is photographed by a scanning electronic microscope (SEM). A circle having an area A is depicted on the photograph. The number of grains contained in the circle, excluding those grains coinciding on the circumference of the circle, is defined as Na, the number of grains coinciding on the circumference of the circle as Nb, and the magnification of the SEM as M. The average grain size D is calculated as follows and the average grain size thus calculated is considered as the sintered grain size.
[0065] Number of grains in the circle Nc: Nc=Na+(1/2)×Nb
[0066] Number of grains per unit area Ng: Ng=Nc/(A/M 2 )
[0067] Average grain size D: D=√(1/Ng)
[0068] In this calculation, the sectional shape of a grain is regarded as being square in view of an area of 1/Ng occupied by one grain.
[0069] M is set to 8000 or more and the circle is depicted such that the relationship of Nc≧100 holds. If such circle cannot be depicted on the photograph, the magnification is decreased and then photographing is performed again. If a circle satisfying the relationship of Nc≧100 cannot be depicted on the photograph with the magnification of 8000, a plurality of photographs that do not overlap each other are taken and a circle is depicted on each photograph. The total Nct of Nc for each circle should satisfy the relationship of Nct≧100. Then, Ng is calculated as follows:
[0070] Number of grains per unit area Ng: Ng=Nct/(At/M 2 )
[0071] where Nct denotes the total of Nc for each circle and At denotes the total of area A for each circle.
[0072] The surface roughness is measured by a method conforming to “JIS B0601” (2001 edition).
3. Confirmation Test for Merit (Durability) of Implant Fixture
[0073] (1) Preparation of Specimens
[0074] (i) Specimen A
[0075] Specimen A was prepared by substantially the same method as the method of manufacturing an implant fixture as mentioned above. Specimen A was a plate in shape having dimensions of 30 mm×5 mm×2 mm. The denseness (relative density) of Specimen A was 99% or more and the sintered grain size thereof was 0.15 μm. The arithmetic average roughness Ra of Specimen A was 1.6 μm and the maximum height Rz thereof was 21 μm.
[0076] (ii) Specimen B
[0077] Specimen B was prepared by substantially the same method as Specimen A, but the burning temperature was not 1300° C. but 1400° C. The denseness (relative density) of Specimen B was 99% or more and the sintered grain size thereof was 0.28 μm. The arithmetic average roughness Ra of Specimen B was 1.8 μm and the maximum height Rz thereof was 21 μm.
[0078] (iii) Specimen C
[0079] Specimen C was prepared by substantially the same method as Specimen A, but the burning temperature was not 1300° C. but 1550° C. The denseness (relative density) of Specimen C was 99% or more and the sintered grain size thereof was 0.41 μm. The arithmetic average roughness Ra of Specimen C was 1.5 μm and the maximum height Rz thereof was 14 μm.
[0080] (iv) Specimen R
[0081] A precursor was prepared by substantially the same method as Specimen A, but the precursor was a plate in shape having dimensions of 30.1 mm×5.1 mm×2.1 mm. One of the surfaces of the precursor was polished with a planar polisher and then subjected to blasting. This surface was a surface of which the monoclinic percentage was measured later. Thus, Specimen R was prepared to have dimensions of 30 mm×5 mm×2 mm. Ceramic beads having an average grain size of 280 μm were used as blast media. Blast pressure was 0.5 Kgf/cm 2 . A pen-type sandblaster was used in blasting.
[0082] The denseness (relative density) of Specimen R was 99% or more and the sintered grain size thereof was 0.15 μm. The arithmetic average roughness Ra of Specimen R was 2.2 μm and the maximum height Rz thereof was 16 μm.
[0083] (v) Specimen X
[0084] First, Specimen R was prepared. Then, it was subjected to annealing treatment in order to reduce the monoclinic percentage. Thus, Specimen X was prepared. The annealing treatment was performed at a burning temperature of 1000° C. for two hours. The denseness (relative density) of Specimen X was 99% or more and the crystalline grain size thereof was 0.15 μm. The arithmetic average roughness Ra of Specimen X was 2.2 μm and the maximum height Rz thereof was 22 μm.
[0085] (2) Testing Method
[0086] The monoclinic percentage (volume %) was measured in respect of each specimen. Then, each specimen was dipped in a 1% solution of L-lactic acid having a temperature of 35° C. The monoclinic percentage of each specimen was measured one day, ten days, one month, three months, and six months after the dipping was started.
[0087] (3) Testing Results
[0088] Testing results are shown in Table 1 below.
[0000]
TABLE 1
Monoclinic Percentage (volume %)
One
3
Before
One day
10 days
month
months
6 months
Specimen
dipping
after
after
after
after
after
A
0
0
0
0
0
0
B
0
0
0
0
0
0
C
0
0
0
0
2
9
R
3
5
10
20
25
Collapsed
X
0
0
0
2
8
15
[0089] Note: “Collapsed” indicates that the surface of the specimen was collapsed and the monoclinic percentage could not be measured.
[0090] As is clearly known from the table, Specimens A, B, and C each showed much lower monoclinic percentage, compared with Specimen R. Further, the monoclinic percentage of Specimens A, B, and C hardly increased even after the specimens had been dipped in the lactic acid solution for a long time. Especially, Specimens A and B, which were burned at 1400° C. or less and had a sintered grain size of 0.3 μm or less, showed this tendency most.
[0091] In contrast with Specimens A and B, Specimen R had a polished surface and showed high initial monoclinic percentage before dipping. The monoclinic percentage of Specimen R rapidly increased while it was dipped in the lactic acid solution, and the surface of Specimen R was collapsed 6 months after the dipping was started.
[0092] The monoclinic percentage of Specimens A, B, and C showing low initial monoclinic percentage hardly increased even after they had been dipped in the lactic acid solution. It has been confirmed that Specimens A, B, and C were excellent in durability and that they had appropriate surface roughness.
[0093] The implant fixture 1 was actually implanted and used in a living organism. It was excellent in resistance against lactic acid or the like. The implant fixture 1 had high affinity and compatibility with a living organism (high bioaffinity and biocompatibility).
4. Confirmation Test for Merit (Osseointegration) of Implant Fixture
[0094] (1) Preparation of Specimens
[0095] (i) Specimen Aa
[0096] Specimen Aa was prepared by substantially the same method as Specimen A. Specimen Aa was substantially the same in shape as the implant fixture as mentioned earlier. The portion to be buried in bone was a screw in shape having a diameter φ of 3.0 mm and a length of 9 mm with a pitch of 1.2 mm and a groove depth of 0.4 mm. The arithmetic average roughness Ra of Specimen Aa was 2.0 μm and the maximum height Rz thereof was 23 μm.
[0097] (ii) Specimen Ba
[0098] Specimen Ba was prepared by substantially the same method as Specimen B. Specimen Ba was substantially the same in shape as Specimen Aa. The arithmetic average roughness Ra of Specimen Ba was 1.8 μm and the maximum height Rz thereof was 22 μm.
[0099] (iii) Specimen Ca
[0100] Specimen Ca was prepared by substantially the same method as Specimen C. Specimen Ca was substantially the same in shape as Specimen Aa. The arithmetic average roughness Ra of Specimen Ca was 1.7 μm and the maximum height Rz thereof was 18 μm.
[0101] (iv) Specimen Xa
[0102] Specimen Xa was prepared by substantially the same method as Specimen X. Specimen Xa was substantially the same in shape as Specimen Aa. The arithmetic average roughness Ra of Specimen Xa was 2.2 μm and the maximum height Rz thereof was 23 μm.
[0103] (v) Specimen Ya
[0104] Specimen Ya was prepared by substantially the same method as Specimen Aa. During the preparation of the specimen, the surface of the master model 21 was not subjected to blasting. The arithmetic average roughness Ra of Specimen Ya was 0.3 μm and the maximum height Rz thereof was 2 μm.
[0105] (2) Testing Method
[0106] Each specimen was implanted in the second mandibular molar of a beagle dog that was one or two years old. Four weeks after, the dog's jawbone having the specimen implanted therein was taken out. Then, the jawbone was fixed and a torque required for removing the implanted specimen from the jawbone was measured.
[0107] Specifically, the specimen was removed from the jawbone with a driver dedicated for the implant fixture that was connected to a torque meter. The maximum torque detected by the torque meter via the driver was defined as pulling torque strength. Testing was performed on each specimen with N=3.
[0108] (3) Testing Results
[0109] Measured pulling torque strength of each specimen was shown below. The numeric values shown below are averages when N=3.
Specimen Aa: 32 N·cm (newton centimeter) Specimen Ba: 29 N·cm Specimen Ca: 28 N·cm Specimen Xa: 32 N·cm Specimen Ya: 16 N·cm
[0115] The pulling torque strength is a measured value reflecting the achieved osseointegration. As is clearly known from the testing results, the osseointegration differed depending upon the surface roughness. Compared with Specimen Ya having small surface roughness, other specimens having large surface roughness achieved better osseointegration and were stably fixed in the jawbone.
[0116] The present invention is not limited to the embodiment described so far. Various modifications of the example embodiment, as well as other embodiments of the invention, which are apparent to persons skilled in the art to which the invention pertains, are deemed to lie within the spirit and scope of the invention.
[0117] For example, the material of the master model is not limited to SUS, and other metals such as brass may be used.
[0118] The implant fixture 1 illustrated in FIG. 1 is a one-piece implant fixture integrally including the buried portion 1 a and the exposed portion 1 b. The shape of the implant fixture is not limited to the one illustrated in FIG. 1 . Arbitrary shapes may be used. For example, a two-piece implant fixture may be employed, including a separate buried portion and a separate exposed portion. In this case, the buried portion acts as an implant fixture and the exposed portion acts as an abutment. A female screw is provided in the implant fixture and a male screw is provided in the abutment. The abutment may be fixed onto the implant fixture by screwing the male screw of the abutment into the female screw of the implant fixture.
[0119] The manufacturing method of the implant fixture is not limited to the one described herein. Other methods may be employed. For example, sintered ceramics are ground according to the shape illustrated in FIG. 1 and then subjected to annealing treatment. According to this alternative method, the monoclinic percentage in the sintered ceramics is high immediately after the grinding. The monoclinic percentage may be reduced by annealing treatment. However, the implant fixture manufactured as described earlier has higher resistance against lactic acid or the like than the one manufactured by the alternative method. | A method of manufacturing a sintered ceramic implant fixture that includes a first portion configured to be buried in tissue of a living organism and a second portion configured to serve as a mount for a superstructure. The method includes fabricating a master model, subjecting the master model to blasting to roughen a surface of the master model, fabricating a mold having a cavity that is defined by the master model having the roughened surface, pouring a slurry containing ceramic powder into the cavity of the mold to obtain a hardened but not-yet-sintered ceramic implant fixture, and sintering the hardened but not-yet-sintered ceramic implant fixture to obtain the sintered ceramic implant fixture. | 0 |
FIELD OF THE INVENTION
[0001] The present invention refers to hydroxyapatite and bioglass-based pellets, their production process and respective applications, particularly as a synthetic bone graft. Such clinical applications are applied in all areas that include surgery and medicine, particularly those which are directly related with bone replacement and regeneration, such as orthopaedic surgery, maxillofacial surgery, dental surgery and implantology.
BACKGROUND OF INVENTION
[0002] The bone is a complex mineralized tissue that exhibits rigidity and strength while maintaining a certain degree of elasticity, two forms existing, the primitive bone and lamellar bone. The first class is an immature bone that is formed during embryonic development, cicatrisation and fracture healing processes, tumours and metabolic diseases. Its structural organization is random. The lamellar bone is a more mature bone that gradually replaces the primitive bone, represents the major class of bone in the adult skeleton possessing a well organized structure. Namely, is constituted by cortical bone (external bone region) and trabecular bone (internal bone region). The cortical bone is characterized by cylindrical canals (osteons), united by a rigid tissue matrix which is essentially composed by hydroxyapatite. Collagen cylindrical fibres (the main organic component of bone) fill the pores (190-230 μm) of this kind of bone. The inorganic matrix of the cortical bone consists of a structure with approximately 65% interconnective porosity. On the other hand, the trabecular bone differs from the cortical bone by showing further empty spaces and non-cylindrical pores filled with collagen. Trabecular bone pores, in the range of 500-600 μm are larger than cortical bone pores. Therefore, it becomes apparent that due to its intrinsic complex structure, the bone is one of the most difficult tissues to mimic.
[0003] Currently, average life expectancy is twice as high as in the beginning of the 20 th century, resulting in a progressive tissue functionality loss. Of note, the incapacity associated to orthopaedic degeneration clinical challenges, which is considered a major social problem in modern society's aged populations. Actually, the bone is the second most transplanted material to the human body, only preceded by blood. Bone defects resulting from trauma, tumour resection, fracture non-union and congenital malformations are common clinical problems.
[0004] The consensual gold standard graft remains the autologous graft, consisting of bone collection in one site and transplantation to another site of the same individual. These grafts possess limitations concerning amount availability, as well as, the invasive nature of the harvest procedure. Due to their autologous origin, these grafts eliminate the risk of infection transmission (Human Immunodeficiency Virus, Hepatitis viruses, Creutzfeldt-Jakob disease) and/or of immunological rejection. However, high morbidity associated to donor site, as well as, local pain associated with the invasive harvest procedure extend the hospitalization period.
[0005] The alternatives to autologous grafts are allogenic grafts from post mortem human bone tissue and xenografts (non-human animal origin). Their clinical application introduces the possibility of immunological rejection, presents logistics problems and risk of infectious disease transmission to the recipient, which is currently a major concern of physicians, particularly in the case of viral diseases.
[0006] The use of synthetic bone grafts, namely, calcium phosphate ceramics, presents itself as the valid reference alternative due to its osteointegration ability. Hydroxyapatite, Ca 10 (PO 4 ) 6 (OH) 2 , and tricalcium phosphate, Ca 3 (PO 4 ) 2 , comprise the most commonly used calcium phosphate ceramics in the clinical field owing to their similarity with bone mineral phase, and due to their biocompatibility, bioactivity and osteoconductivity properties.
[0007] Several studies attempted to obtain a production method of synthetic bone grafts with a micro and macroporous structure similar to the micro and macrostructure present in natural mineral bone (1-4). These studies focused their objectives in obtaining macrostructure, porosity, pore size, distribution and interconnectivity, which culminates in optimum osteoregeneration. Specifically, microporosity enhances cell adhesion and macroporosity foments bone growth within the bone graft, these factors being decisive for the increase in new bone growth rate locally at the implant site, as described below.
[0008] Attaining porosity in bone grafts has comprehended several methodologies, including foam and polymeric sponges-based technology and porogenic agents (1-4). In the first case, foams or polymeric sponges are impregnated with a biomaterial suspension and, upon drying, are processed by a thermal process which assures full combustion of the foam or sponge and concomitant formation of open pores (1, 2). The second technique employs different porogenic substances, such as organic additives and inorganic salts, which upon mixture with the ceramic biomaterial and subsequent appropriate thermal treatment, result in porous structures (3, 4).
[0009] However, these methods present recurring disadvantages that are due to non-controlled biomaterial retraction and residue presence after sintering, difficulty in controlling pore dimension, distribution and interconnectivity, and concomitant process reproducibility, presenting consequences at the level of cell colonization of the material. Additionally, elevated porosity percentages are associated to considerable mechanical resistance reduction compromising the clinical applications of the synthetic bone graft. On the other hand, in resorbable bone grafts, high porosity and consequent increase in specific surface area resulting in precocious resorption that might compromise bone regeneration due to the absence of physical support, as well as, to the induction of an inflammatory process. Therefore, a compromise between resorption rate and new bone growth rate becomes vital. In such compromise, and despite the reduction in mechanical resistance associated with the bone graft resorption rate, adequate percentages of micro and macroporosity will overpass those effects via bone cell and blood vessel ingrowth, which are the fundamental features for bone graft osteointegration.
[0010] Porosity characterized by pores with diameters equal to 100 μm is the fundamental condition for the capillary vascular growth and for the establishment of osteoprecursor cell-bone graft interactions which are essential for the growth and cell reorganization within the synthetic graft. Micro and macroporosity and pore interconnectivity degree, directly affect the diffusion of gas and nutrients present in physiological fluids, as well as, the metabolic residue removal. As cell growth occurs into the interior of the porous canals the bone graft acts as a structural bridge for bone regeneration.
[0011] Due to the abovementioned, the development of implantable biomaterials with porosity that mimics as much as possible the bimodal bone structure (cortical and trabecular) and that presents adequate interconnectivity degree, represents a tremendous challenge.
[0012] The present invention relates to a production process of hydroxyapatite and bioglass-based pellets (5), of homogeneous size and spherical shape, whose interconnective porous structure, in the micrometer range, allows for enhanced osteoconductivity and osteointegration. This kind of micro and macroporous structure is a fundamental requirement for the occurrence of cell adhesion and bone tissue growth within the material, which constitutes the first essential advantage of this novel biomaterial. The reproducibility of the pharmaceutical processes of extrusion and spheronization guaranties the above-mentioned characteristics, which in turn translates in a biomaterial whose behaviour is completely controlled and expected upon implantation. Additionally, the adaptation ability of spherical pellets to the form and geometry of the bone defect is extremely relevant, becoming also a fundamental advantage for the occurrence of enhanced osteoconduction and osteointegration.
[0013] The document WO 0068164 (5) discloses a material with applications as a bone graft, obtained through the reaction between a bioglass and hydroxyapatite, via a sintering process in the presence of a vitreous liquid phase that guaranties bioglass fusion and diffusion into hydroxyapatite structure which culminates in several ionic substitutions within its matrix. Such phenomenon confers the following characteristics to the bone graft: (a) Superior bioactivity, due to the reproduction of bone inorganic phase which contains several ionic species that modulate its biological behaviour, (b) Enhanced mechanical properties owing to the utilization of a bioglass of the CaO—P 2 O 5 system that acts as liquid phase during the hydroxyapatite sinterization process and that, by filling the material pores, increases its density, and consequently, its mechanical resistance. Nevertheless, the bone graft production process described in the document WO 0068164 (5), does not result in a final product with a porous structure similar to the one of mineral bone, neither a macrostructure (or global geometry) considered ideal for clinical application in bone defects. The present invention discloses a production process of a bone graft comprising a bioglass, hydroxyapatite and at least one porogenic agent, through the pharmaceutical technology of extrusion and spheronization and a thermal process of sintering in the presence of a vitreous liquid phase. This process originates: (a) pellets, with spherical geometry considered ideal for the adaptation of the material to bone defects; (b) pellets with highly controlled micro and macroporous structures, which depends on the porogenic agent or porogenic agents used, and which is responsible for the osteoconduction and osteointegration of the bone graft.
[0014] Usually, market available synthetic bone grafts are produced in the form of granules obtained via a dry granulation process (U.S. Pat. No. 5,717,006 (6) and U.S. Pat. No. 5,064,436 (7)). Briefly, ceramic blocks, previously obtained by pressing and sinterization, are submitted to milling and size segregation. Despite the granules obtained accordingly to the mentioned method might present porosity, they exhibit irregular and angular geometry susceptible of inducing inflammatory reactions due to differences between individual granule reabsortpion rates and eventual tissue damage provoked by edges. Furthermore, the above-mentioned geometric irregularity makes the granules unsuitable for controlled drug release, due to the difficulty of a uniform coating with an active pharmaceutical substance. The biomaterial described in the present invention does not possess the previously mentioned disadvantages since it has a spherical form that is perfectly replicated via the extrusion and spheronization processes.
[0015] While US200406777001 (8) discloses a calcium phosphate ceramic sphere obtaining method consisting of the controlled dropping of the ceramic suspension into a low temperature medium, followed by a lyophilisation treatment of the frozen ceramic droplet and posterior sinterization, resulting in dense spheres, the production process disclosed in the present invention employs a pharmaceutical production process of extrusion and spheronization and a porogenic agent or agents for the production of hydroxyapatite and bioglass-based pellets (5), characterized by controlled aspect ratio and porosity, with diameters up to 10 mm. Moreover, and conversely to the process described in US200406777001 (8), the production process of the present invention is an automated, low cost and high productivity process, that during a short time span yields pellets of controlled aspect ratio and porosity, which allow for cellular adhesion and bone tissue ingrowth within the material.
[0016] While the process of pharmaceutical technology of extrusion and spheronization disclosed in EP1719503 (9) exclusively refers to the production of pellets with a formulation based on a debranched starch, several excipients and one or more active pharmaceutical agents, the production process disclosed in the present invention is based on the pharmaceutical technology of extrusion and spheronization using a porogenic agent or agents and hydroxyapatite sintering in the presence of a vitreous liquid phase in order to attain hydroxyapatite and bioglass-based ceramic pellets with controlled aspect ratio and porosity.
GENERAL DESCRIPTION OF THE INVENTION
[0017] The present invention refers to hydroxyapatite and bioglass-based pellets, their production process and respective applications, particularly in osteoregenerative medicine as a bone graft.
[0018] The production process of these pellets is based in the pharmaceutical technology of extrusion and spheronization using a porogenic agent and a sintering process of hydroxyapatite in the presence of vitreous liquid phase, resulting in a low cost, high reproducibility, high yield and productive capacity. This process originates pellets with a granulometry superior to 10 mm, showing controlled porosity characterized by two pore populations. The pellets present homogeneous size and spherical shape, and an interconnective porous structure in the micrometer range.
1. Pellet Characteristics
[0019] The structures disclosed in the present invention are spherical-shaped, hydroxyapatite and bioglass-based, with a global porosity of at least 40 vol %, comprising an intraporosity (biomaterial pores) of at least 20 vol % and an interporosity (pores resulting from the biomaterial packing) of at least 20 vol %. The intraporosity, dependent on pellet size and on the porogenic agent used, is characterized by the presence of several distinct populations of pores: microporosity, with pores comprising diameters up to 5 μm; mesoporosity, with pores comprising diameters from 5-50 μm; macroporosity, with pores comprising diameters superior to 50 μm. The interporosity, dependent on pellet size, has pores comprising diameters superior to 10 μm.
2. Pellet Production Process
[0020] In the present invention, hydroxyapatite is prepared according to a precipitation method resulting from the reaction between a calcium hydroxide suspension (Ca(OH) 2 ) in purified water and an aqueous solution of orthophosphoric acid (H 3 (PO 4 ) 2 ).
[0021] The bioglass employed in the production process of the present invention, belongs to the P 2 O 5 —CaO system, in a ratio of molar percentages of 20:80 to 80:20, with the possible nominal composition: CaF 2 (0-20 mol %), Na 2 O (0-20 mol %) and MgO (0-20 mol %).
[0022] Bioglass preparation is performed via fusion of a sodium source (e.g., sodium carbonate (Na 2 CO 3 )), a calcium source (e.g., calcium hydrogenophosphate (CaHPO 4 )), a fluor source (e.g., calcium fluoride (CaF 2 ), magnesium source (e.g., magnesium oxide (MgO)) and a phosphorus source (diphosphorus pentoxide(P 2 O 5 )).
[0023] Following the preparation of the abovementioned raw-materials, milling and sieving is performed in order to obtain particles with a granulometry up to 75 μm.
[0024] Afterwards, the biocompatible glass is added to hydroxyapatite in a weight percentage inferior to 10% relatively to the hydroxyapatite weight.
[0025] A porogenic agent, as disclosed in the present invention, is defined as any appropriate substance that makes the product suitable for extrusion and spheronization processes, having the ability to absorb and expand upon water retention and that upon sintering, suffers complete calcination not leaving any residue thus originating a porous structure. Preferably, the porogenic agent used ought to be at least one among cellulose, starch, modified starch, sorbitol, croscarmellose sodium, crospovidone, sodium alginate and lactose, among others, up to 80 wt % of the final mixture. The weight percentage at which the porogenic agent or agents are added is vital because besides accomplishing the desired porosity of the final biomaterial, it guaranties the desired plasticity of the initial paste, which is fundamental during the extrusion process. Paste plasticity is conferred through the hydration capacity of the porogenic agent or agents used, that upon mixture with hydroxyapatite and bioglass form an adequate plastic mixture for extrusion and spheronization, originating pellets of controlled aspect ratio and porosity.
[0026] The mixture procedure between hydroxyapatite, bioglass and porogenic agent or agents is performed via a dry process, employing a mixer, e.g., a double cone mixer, at a rate up to 100 rotations per minute (rpm) and during a period of time always superior to 5 minutes, in order to obtain a homogeneous powder blend that allows reproducibility of final product phase composition.
[0027] Subsequent to the powder dry mixture procedure, the granulation liquid, purified water, is gradually added at percentages between 50 wt % and 150 wt % relatively to powder mixture weight, depending on the porogenic agent or agents used and their respective water absorption capacity. The gradual addition is performed in a mixer, e.g., planetary mixer, in which the mixture is subsequently submitted to malaxation at a rate never inferior to 100 rpm for a period of time never inferior to 5 minutes, so as to attain a homogeneously lubrified paste. The moist paste obtained is then hydrated throughout a time period that can vary between 0.5 h and 36 h. These procedures have the purpose of granting appropriate rheologic properties, namely, plasticity and cohesion, which make the extrusion process of the mixture of hydroxyapatite, bioglass and porogenic agent or agents feasible.
[0028] After finalizing the hydration period, extrusion of the moist paste is performed using an extruder, e.g., roll extruder, provided with an extrusion screen up to 10 mm, at a rate inferior to 50 rpm. The extruder and screen type, as well as the extrusion rate greatly influence the extrudate characteristics. The roll extruder combines low pressure extrusion and low heat production with minimum water movement resulting in high product densification. The extrusion rate, the screen configuration and the extrusion temperature, significantly affect the water lubricant effect and the rheologic properties of the extrudate, consequently influencing the properties of the obtained pellets.
[0029] Next, the obtained extrudate is placed in a spheronizer that will never attain a rate inferior to 100 rpm, during a period of time never inferior to 1 minute. Spheronization rate is directly associated with the desired pellet size. Additionally, spheronization rate variations have a direct effect on the density, the hardness, spherical shape, porosity and superficial morphology of the pellets.
[0030] The attained pellets are dried in a forced air circulation oven, at a temperature never inferior to 60° C., until the water content in the pellets does not exceed 5 wt %. This drying procedure ensures the proper, structure non-damaging pellet manipulation before the sintering process.
[0031] Then, a thermal treatment of the pellets is performed, through temperature increase at a rate of 0.1-4° C./min, preferably at 0.5° C./min, until a temperature in the range of 400-800° C., preferably 600° C., is reached. The thermal treatment at the mentioned temperature takes place during a period of time not inferior to 1 h and 30 min in order to ensure the complete combustion of the porogenic agent or agents employed, without leaving residue while originating the porous structure.
[0032] Relatively to the sintering process, this should be performed above 1200° C., at a heating rate of 4° C./min, preferably at a temperature between 1250° C. and 1350° C., allowing the bioglass fusion and distribution in the hydroxyapatite matrix in a liquid phase sintering process. Once the sintering temperature is reached, the sintering thermal treatment in the presence of a vitreous liquid phase occurs during a period of time not inferior to 1 h, followed by the posterior natural cooling of the biomaterial to room temperature inside the furnace.
3. Advantages of the Pellet Production Process
[0033] The obtained structure of the hydroxyapatite and bioglass-based bone graft using the production process described in the present invention possesses several advantages.
[0034] The described process in the current invention presents low cost, high reproducibility, higher yield and productive capacity of the synthetic bone graft.
[0035] Concerning the reached porous structure, cell adhesion promotion and consequent cellular growth, namely, of osteoprecursor cells and blood vessels, induced by the release of ionic species from the biomaterial that culminates in a higher osteointegration and osteoregeneration are the main advantages. Furthermore, native conformation protein adsorption, present in physiological fluids, at the porous surface of the synthetic bone graft, contributes to an absent immunogenicity and a cellular proliferation increase.
[0036] The spherical shape of the pellets results in an adequate ability of injection and adaptation to any kind of bone defect. Therefore, the bone graft of the present invention could be used as an injectable composite material, consisting of the base biomaterial associated with a common biocompatible polymeric vehicle for minimal invasive surgery applications.
[0037] The homogenous size and spherical shape, and interconnective porosity of the pellets, further allow its application as a controlled pharmaceutical active substance release device, such as growth factors or other growth modulation and bone remodelling agents.
[0038] The synthetic bone graft pellets disclosed in the current invention have, therefore, several applications in osteoregenerative medicine, particularly in the fields of orthopaedic surgery, maxillofacial surgery, dental surgery, implantology and as tissue engineering scaffolds.
DESCRIPTION OF THE DRAWINGS
[0039] FIGS. 1A and 1B : Pellets of 500-1000 μm granulometry, hydroxyapatite and bioglass-based, with controlled aspect ratio and porosity, prepared according to the method disclosed in the present invention, and observed by scanning electron microscopy (SEM).
[0040] FIG. 2 : Granulometric distribution of hydroxyapatite and bioglass-based pellets with controlled aspect ratio and porosity, obtained with an extrusion screen of 1 mm, which reflects the reproducibility, higher yield and productive capacity of the method disclosed in the present invention.
[0041] FIG. 3 : Pore distribution, mercury porosimetry-determined, of hydroxyapatite and bioglass-based pellets, obtained with an extrusion screen of 1 mm.
DETAILED DESCRIPTION OF THE INVENTION
1. Pellet Production Process
[0042] The pellet production process of the present invention comprises hydroxyapatite and a bioglass of P 2 O 5 —CaO system preparation according to the following procedures:
1.1. Hydroxyapatite Preparation
[0043] Hydroxyapatite is prepared by precipitation of the product resulting of the reaction between a calcium hydroxide (Ca(OH) 2 , >98%) suspension in purified water and an aqueous solution of orthophosphoric acid 85(wt/v) % (H 3 (PO 4 ) 2 ) according to the following chemical reaction:
[0000] 10Ca(OH) 2 +6 H 3 (PO) 4 →Ca 10 (PO 4 ) 6 (OH) 2 +18H 2 O
[0044] After the preparation of the abovementioned raw material, milling and sieving are performed in order to obtain particles with a granulometry inferior to 75 μm.
1.2. Bioglass Preparation
[0045] The biocompatible glass with nominal composition [60-75%]P 2 O 5 -[0-25%]CaO-[0-15%]Na 2 O-[0-15%]CaF 2 -[0-20%]MgO (molar %) is prepared through a conventional melting process.
[0046] After the preparation of the abovementioned raw material, milling and sieving are performed in order to obtain particles with a granulometry inferior to 75 μm.
1.3. Raw Material Mixture
[0047] Afterwards, the bioglass is added to hydroxyapatite at a weight percentage inferior to 10% relatively to hydroxyapatite weight.
[0048] The addition of one or more porogenic agents to the hydroxyapatite and bioglass mixture is then performed, using at least, among others, cellulose, starch, modified starch, sorbitol, croscarmellose sodium, crospovidone, sodium alginate and lactose, up to 80 wt % of the final mixture.
[0049] The mixture procedure between hydroxyapatite, bioglass and porogenic agent or agents is performed via a dry process, employing a mixer, e.g., a double cone mixer, at a rate up to 100 rotations per minute (rpm) and during a period of time always superior to 5 minutes.
[0050] Subsequent to the powder dry mixture procedure, the granulation liquid, purified water, is gradually added at a percentage between 50 wt % and 150 wt % relatively to powder mix, depending on the porogenic agent or agents used and their respective water uptake. The gradual addition is performed in a mixer, e.g., planetary mixer, in which the mixture is subsquently, submitted to malaxation at a rate never inferior to 100 rpm during a period of time never inferior to 5 minutes.
[0051] The moist paste obtained is then hydrated throughout a time period that can vary between 0.5 h and 36 h.
1.4. Extrusion Process
[0052] Once the hydration period is complete, extrusion of the moist paste is performed using an extruder, e.g. roll extruder, provided with an extrusion screen up to 10 mm, at a rate inferior to 50 rpm.
1.5. Spheronization Process
[0053] The obtained extrudate is placed in a spheronizer that will never attain a rate inferior to 100 rpm, during a period of time never inferior to 1 minute.
1.6. Thermal Treatment
[0054] The attained pellets are dried in a forced air circulation oven, at a temperature never inferior to 60° C., until the water content in the pellets does not exceed 5 wt %.
[0055] Then, a thermal treatment of the pellets is performed, through temperature increase at a rate of 0.1-4° C./min, preferably at 0.5° C./min, until a temperature in the range of 400-800° C., preferably 600° C., is reached, during a period of time not inferior to 1 h and 30 min.
[0056] As far as the sintering process is concerned, this should be performed above 1200° C., at a heating rate of 4° C./min, preferably at a temperature between 1250° C. and 1350° C., using a liquid phase sintering process. Once the sintering temperature is reached, the sintering thermal treatment in the presence of a vitreous liquid phase occurs during a period of time not inferior to 1 h, followed by the subsequent natural cooling of the biomaterial to room temperature inside the furnace.
2. Pellet Characterization
[0057] The present invention discloses the production of synthetic hydroxyapatite and bioglass-based bone graft pellets, presenting a formulation up to 10 wt % of bioglass relatively to hydroxyapatite weight, and up to 80 wt % of at least a porogenic agent relatively to the hydroxyapatite and bioglass powder mixture weight.
[0058] The pellets disclosed in the present invention are characterized by a global porosity of at least 40 vol %, comprising an intraporosity (biomaterial pores) of at least 20 vol % and an interporosity (pores resulting from the biomaterial packing) of at least 20 vol %. The intraporosity, dependent on pellet size and on the porogenic agent used, is characterized by the presence of several distinct populations of pores: microporosity with pores comprising diameters up to 5 μm; mesoporosity with pores comprising diameters from 5-50 μm; macroporosity with pores comprising diameters superior to 50 μm. The interporosity, dependent on pellet size, is characterized in that it includes pores comprising diameters superior to 10 μm.
[0059] The present invention required granulometric distribution analysis through sieving, pore distribution analysis, porosity, surface area, average pore diameter, bulk and apparent density by means of mercury porosimetry. Pellet surface morphology was assessed by scanning electron microscopy (SEM). Additionally, resistance to crushing, the measurement of the necessary force to fracture the pellets, was performed. The pellet spherical degree was observed and calculated via aspect ratio (width/height) determination under an optical microscope. Such determination consists in calculating the ratio between the largest distance of a pellet (length) and the corresponding perpendicular dimension (height).
EXAMPLES
Example 1
Hydroxyapatite, Bioglass-Based with at Least a Porogenic Agent Pellet Preparation with a Granulometry Between 500 to 1000 μm
Hydroxyapatite Preparation
[0060] 500.00 g hydroxyapatite are prepared by chemical precipitation according to the following chemical reaction:
[0000] 10Ca(OH) 2 +6H 3 (PO) 4 →Ca 10 (PO 4 ) 6 (OH) 2 +18H 2 O
[0061] In order to achieve that, 370.45 g calcium hydroxide (Ca(OH) 2 , >98%), 345.15 g orthophosphoric acid 85 (wt/v) % (H 3 PO 4 ) are weighed. 9 L purified water are poured in a large appropriated container, calcium hydroxide is added and mixed (Mixer R25) for 15 minutes. Meanwhile, 8 L purified water are poured in an appropriated recipient, orthophosphoric acid is added and the volume is completed with purified water up to 9 L. The addition of orthophosphoric acid is carried out via peristaltic pump (Minipuls 2) at a constant rate of 150 rpm. The mixture is performed for 4-5 hours, and cleaning of the calcium hydroxide container walls with purified water is required in order to prevent precipitate accumulation. Throughout the process, a pH control using a 32% ammonia solution is performed in order to maintain the pH higher than 10.5±0.5. After the acid solution addition, the container is washed with purified water and the rate of the peristaltic pump is increased to 360 rpm. Once the mixture is complete, the solution in the container is stirred for 1 hour followed by a resting period for of 16 hours where the mixture is left ageing. Afterwards, hydroxyapatite filtration is performed and dried in a forced air circulation oven (Binder). Once dried, hydroxyapatite is milled in a planetary mill (Fritsch Pulverizette 6) and sieved until a granulometry inferior to 75 μm is achieved.
Bioglass Preparation
[0062] 0.2 mol of a bioglass with the following nominal composition 65% P 2 O 5 -15% CaO-10% CaF 2 -10% Na 2 O (molar o) is prepared, wherein fluoride ion source is CaF 2 . In order to achieve that, 2.12 g sodium carbonate (Na 2 CO 3 ), 4.08 g calcium hydrogenophosphate (CaHPO 4 ), 1.56 g calcium fluoride (CaF 2 ) and 16.32 g diphosphorus pentoxide (P 2 O 5 ) are weighed and mixed in a platinum crucible. The crucible is placed in a vertical furnace (Termolab) and heated for 1 h 30 min until 1450° C. are reached, followed by a dwelling time of 30 minutes, after which the molten glass is poured into purified water. Once the glass is dry, it is milled in a planetary mill (Fritsch Pulverizette 6) and sieved until a granulometry inferior to 75 μm is achieved.
Pellet Preparation
[0063] 487.50 g hydroxyapatite, 12.50 g bioglass and 500.00 g microcrystalline cellulose (Avicel PH101, with a diameter inferior to 50 μm) are mixed for 20 minutes at 150 rpm using a double cone mixer (ERWEKA). Then the mixture is placed on a planetary mixer (ERWEKA) and 825.00 mL purified water are gradually added for 5 minutes at 150 rpm. Afterwards, the paste malaxation procedure is performed, in the same ERWEKA planetary mixer at this instant provided with an adapter with planetary movement, for 10 minutes at 300 rpm. After the malaxation period, the moist paste is placed in a polyethylene air-deprived double bag, allowing the hydration of the microcrystalline cellulose for 2 h.
[0064] When the hydration period is complete, the moist paste is placed in a roll Caleva Screen Extruder 20, equipped with an extrusion screen with a 1 mm diameter, and at a rate of rpm the extrusion of the moist paste is performed. Following the extrusion process, the extrudate is placed in a spheronizer (Caleva Spheronizer 250), provided with a 3 mm spheronization plate, the rate is adjusted to 850 rpm and, after a 5 minute spheronization time, the pellets are removed.
[0065] The pellets are dried in a forced air circulation oven (Memmert), at a temperature never inferior to 60° C., until the water percentage in the pellets does not exceed 5 wt %, and a sintering thermal treatment of the pellets is then performed, at a heating rate of 0.5° C./min, up to 600° C. are reached and kept for a 90 minute period, followed by a heating rate of 4° C./min up to 1300° C. being this temperature maintained for 60 minutes, being followed by natural cooling inside the furnace. The first dwell time, performed at 600° C., is intended to attain complete combustion of the microcrystalline cellulose.
[0066] After the sintering, and relatively to the pellets morphology of the current example, these show an aspect ratio of 1.06 ( FIG. 1A and Table 1), and their surface ( FIG. 1B ) is in agreement with the porosity revealed by the mercury porosimetry.
[0067] According to the present example, 97.8%±0.8% of the hydroxyapatite and bioglass-based pellets show a granulometry between 500 and 1000 μm ( FIG. 2 ).
[0068] The pellets obtained according to the disclosed example, show a pore distribution depicted in FIG. 3 , where it is possible to observe intra and interpores (the second and first peaks, respectively). The intraporosity obtained in the present example exhibits interconnective micro and mesopores (the second peak of FIG. 3 ).
[0000]
TABLE 1
Characterization of hydroxyapatite and bioglass-
based pellets obtained by extrusion in a 1 mm
screen and spheronization process.
Global Porosity (%)
45.2 ± 4.4
Intraporosity (%)
24.6 ± 0.9
Interporosity (%)
20.6 ± 3.5
Surface Area (m 2 /g)
0.47 ± 0.04
Bulk Density (g/mL)
1.55 ± 0.20
Apparent Density (g/mL)
2.34 ± 0.02
Crushing Resistance (N)
5.2 ± 1.7
Aspect ratio
1.06 ± 0.05
[0069] Hydroxyapatite and bioglass-based pellet production process of the present example allows 45.2% global porosity resulting in a 0.47 m 2 /g surface area (Table 1). The attained intra and interporosities represent 24.6% and 20.6% in volume, respectively.
[0070] The attained pellets show a bulk density of 1.55 g/mL, an apparent density of 2.34 g/mL and a crushing resistance of 5.2; N (Table 1).
BIBLIOGRAFIC REFERENCES
[0000]
1) Lee L J, Zeng C, Cao X, Han X, Shen J, Xu G. Polymer nanocomposite foams. 2005 . Composites Science and Technology, 65: 2344-2363.
2) Haugen P, Ried V, Brunner M, Will J, Wintermantel E. Water as foaming agent for open cell polyurethane structures. 2004 . Journal of Materials Science: Materials in Medicine, 15: 343-346.
3) Prado da Silva M H, Lemos A F, Gibson I R, Ferreira J M, Santos J D. Porous glass reinforced hydroxyapatite materials produced with different organic additives. 2002 . Journal of Non - Crystalline Solids, 304: 286-292.
4) Nam Y, Yoon J J, Park T. A Novel Fabrication Method of Macroporous Biodegradable Polymer Scaffolds Using Gas Foaming Salt as a Porogen Additive. 2000. J. Biomed Mater Res ( Appl Biomater ), 53: 1-7.
5) Santos J D, Hastings, G W, Knowles J C, Sintered hydroxyapatite compositions and method for the preparation thereof, WO 0068164, 2000.
6) Daculsi G., Weiss P., Delecrin J., Passuti N., Guerin F. Composition for biomaterial; Preparation process, U.S. Pat. No. 5,717,006, 1998.
7) Ogiso M., Ogawa T., Ichitsuka T., Inoue M. Bone prosthetic material, U.S. Pat. No. 5,064,436, 1991.
8) Umezu Y., Arai T. Method of production of ceramics, US200406777001, 2004.
9) Remon J. P., Dukic A., Altieri P. A., Vervaet C., Foreman P. B. Use of debranched starch in extrusion-spheronization pharmaceutical pellets, EP1719503, 2006. | The disclosed subject matter refers to hydroxyapatite and bioglass-based pellets of homogeneous size and spherical shape, whose interconnective porous structure, in the micrometer range, allows for an enhanced osteoconductivity and osteointegration, with specific application as a synthetic bone graft and to the respective production process. The production process is based on the pharmaceutical technology of extrusion and spheronization employing a porogenic agent and applying a sinterization stage in the presence of a vitreous liquid phase, which reverts on behalf of a higher reproducibility, superior yield and greater production capacity. Therefore, the disclosed subject matter is directed to the production of hydroxyapatite and bioglass-based pellets with applications in osteoregenerative medicine, particularly in the fields of orthopaedic surgery, maxillofacial surgery, dental surgery, implantology and as tissue engineering scaffolds | 0 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates to a new and distinct cultivar of Hosta plant, botanically known as Hosta, hereinafter referred to by the cultivar name ‘Stitch in Time’.
[0002] The new plant was discovered by the Inventor during the summer of 2003 as a non-induced, naturally occurring whole plant mutation of Hosta ‘Summer Breeze’ (not patented) at his nursery in Olathe, Kans., USA. Asexual propagation of the new cultivar by division in 2004 in Olathe, Kans. and by tissue culture in 2005 in Waseca, Minn. has shown the unique and distinct characteristics of this new plant are stable and reproduce true to type in successive generations.
SUMMARY OF THE INVENTION
[0003] The following traits have been repeatedly observed and are determined to be the unique characteristics of ‘Stitch in Time’. These characteristics in combination distinguish the new Hosta as a new and unique cultivar:
1. Medium sized clump; 2. Dark green narrow-centered leaves with a very wide yellow margin which comprises approximately 80% of the leaf area; 3. A unique gathering or stitching effect where the green and yellow leaf tissues meet; and 4. Pale lavender flowers.
[0008] The new Hosta can be compared to its parent cultivar, ‘Summer Breeze’. In the new Hosta, the margin width is substantially wider than in the Hosta ‘Summer Breeze’. The green center of the new Hosta is reduced proportionately to the increased margin. In addition the parent plant does not show the unique gathering or stitching effect where the green and yellow leaf tissue meets.
[0009] The new Hosta cultivar has not been observed under all possible environmental conditions. The phenotype may vary to some extent with variations in environmental conditions such as temperature, fertility and light intensity, but without any variance in the genotype.
BRIEF DESCRIPTION OF THE PHOTOGRAPHS
[0010] The accompanying color photographs illustrate the overall appearance of the new cultivar including its unique traits as a three year old plant growing in a one gallon container. The colors are as true as is reasonably possible with conventional photography.
[0011] FIG. 1 was taken in July and comprises a top perspective of a typical plant of the new Hosta.
[0012] FIG. 2 was taken in October and shows the front side of an individual leaf with the unique stitching effect between the center and margin tissue.
[0013] FIG. 3 was taken in October and shows the back side of an individual leaf.
DETAILED DESCRIPTION OF THE INVENTION
[0014] In the following description, color references are made to The Royal Horticultural Society's Colour Chart (1995 edition) except where general terms of ordinary dictionary significance are used. The following observations and measurements describe a three-year old plant growing in a one gallon container, as depicted in the accompanying photographs, which was grown outdoors in Olathe, Kans., USA.
Botanical classification: Hosta ‘Stitch in Time’. Parentage: Naturally occurring whole plant mutation of Hosta ‘Summer Breeze’ (non patented. Propagation:
Method.— By division and tissue culture.
Plant description:
Plant habit.— Compact, mounding, symmetrical. Culture.— Light to medium shade in moist soil. Plant type.— Herbaceous rhizomatous perennial. Plant height.— 20 cm (up to about 46 cm at maturity). Plant width.— 38 cm (up to about 107 cm at maturity). Vigor and growth rate.— Moderate. Root system.— Normal, fleshy, branching. Disease resistance.— No known resistance or susceptibility to disease known to Hosta has been observed.
Foliage description:
Leaf shape.— Broadly ovate with a cordate base. Leaf margin.— Entire. Leaf surface.— Slightly dull on top and slightly shiny on bottom. Leaf texture.— Glabrous, moderate to heavy substance, slightly wavy leaf margins. Leaf size.— 10 cm in width, 11 cm in length (increasing to about 18 cm in width and 22 cm in length at maturity). Venation pattern.— Campylodrome with 6 to 8 pairs of veins (increasing to 10-12 vein pairs at maturity). Venation pattern becomes very irregular and contorted in the green centered tissue area. Leaf color.— Dark green center (about RHS 138B) with a very wide golden yellow margin (about RHS 3C). The leaf margin comprises about 80% of the leaf surface and changes to a greenish yellow (about RHS 151D) late in the season.
Petiole description: Plant petioles may have a length of approximately 15 cm with a width of about 13 to 19 mm. The petiole has a central region with a dark green color (about RHS 138B) with a margin having a golden yellow color (about RHS 3C). Flower scape description:
Scape shape.— Round, solid. Scape number.— Each mature eye comprising the clump may produce a single flower scape under normal growing conditions. Scape posture.— Straight, held upright at about 10 to 30 degrees from vertical. Scape size.— About 46 to 76 cm in length, about 5 mm in diameter. Scape color.— Dark green (about RHS 138B). Scape surface.— Glabrous. Leaf bracts.— None observed.
Flower description:
Inflorescence type.— Terminal racemes of single funnel-shaped flowers on elongated scapes. Lastingness of inflorescence.— About 4 weeks in mid-summer from first opening bloom to fading of last opening bloom, individual blooms last about one day. Flower shape.— Funnel-shaped. Flower number.— The number of flowers per raceme varies from about 15 to 30. Flower internode length.— About 2 cm. Flower fragrance.— None detected. Flower bud shape.— Spathulate. Flower bud size.— About 3 cm in length and 1.3 cm in diameter. Flower bud color.— Pale lavender (about RHS 85D). Flower size.— About 5.5 cm in length and 3 cm in diameter. Flower color.— Pale lavender (about RHS 85D). Pedicels.— About 5 mm in length, 2 mm in diameter, RHS 138B in color, glabrous surface. Perianth features.— Comprised of 6 tepals, 3 internal and 3 external, overlapping in expanded region and fused in tube region. Tepal shape.— Oblanceolate with acute apex. Tepal size.— About 5 cm in length and 1 cm in width. Tepal color.— Pale lavender (about RHS 85D). Tepal texture.— Glabrous. Floral bracts.— 1 per flower, ovate in shape, glabrous surface, RHS 138B in color, about 3.5 cm in length and 1 cm in width.
Reproductive organ description:
Gynoecium.— 1 pistil; style is about 5.5 cm in length, 1 mm in diameter, white in color; stigma is 3-lobed and white in color; ovary is superior, compound, composed of 3 locules, RHS 146D in color. Androecium.— 6 stamens; filament is about 5 cm in length, 1 mm in diameter, white in color; anthers are about 3 mm in length, 1 mm in width, RHS 202A in color; pollen is abundant and RHS 15 B in color. Fruit.— Not observed under growing conditions tested. Seeds.— Not observed under growing conditions tested.
Root development: From transfer to rooting media in tissue culture, rooting takes approximately 4 weeks at about 20 degrees Celsius. After transfer from stage III in tissue culture to planting into soil in a greenhouse, a well rooted plant is produced in approximately 8 weeks with a daytime temperature of about 20 degrees Celsius and a soil temperature of about 26 degrees Celsius. | A new and distinct cultivar of Hosta named ‘Stitch in Time’, characterized by its wide yellow colored leaf margins and its unique gathering and stitching where the yellow leaf margin tissue meets the dark green center tissue. | 0 |
FIELD OF THE INVENTION
[0001] The present invention relates to an ink composition excellent in avoiding bronze phenomenon, particularly to an inkjet recording method excellent in avoiding bronze phenomenon and a method for avoiding bronze phenomenon of an image formed by an inkjet recording method.
BACKGROUND OF THE INVENTION
[0002] An inkjet recording method has been rapidly spread and is still developing because it requires inexpensive materials, it enables one to conduct rapid recording, it generates less noise upon recording, and because it permits color recording with ease. The inkjet recording method includes a method of continuous type wherein liquid droplets are continuously ejected and a method of on-demand type wherein liquid droplets are ejected in response to image information signals. Also, the ejection method includes a method of ejecting liquid droplets by applying pressure through piezo elements, a method of ejecting liquid droplets by generating a bubble in an ink through heat, a method of using ultrasonic waves and a method of attracting and ejecting liquid droplets by electrostatic power. As an ink for these inkjet recording methods, there are used aqueous inks, oily inks or solid (melting type) inks.
[0003] Colorants to be used in these inks for the inkjet recording method are required to have a high solubility in a solvent such as water, realize high-density recording, provide a good hue, have excellent fastness against light, heat, active gases in the environment (e.g., oxidative gases such as NO x and ozone, and SO x ), water and chemicals, show an enough good fixability for an image-receiving material not to be blurred, have an excellent keeping quality as an ink, have no toxicity, have a high purity and be available at a low price.
[0004] In particular, it has eagerly been required for dyes to have excellent fastness against light, humidity, heat and, particularly in the case of printing on an image-receiving material having an ink receptive layer containing porous, white inorganic pigment particles, oxidative gases in the environment such as ozone, and have an excellent water resistance.
[0005] On the other hand, it has been known that, in the case of forming a recorded image having a high optical density, dye crystals precipitate on the surface of the recording material as the recording material is dried and, as a result, the recorded image reflects light to give metallic luster, which is called the problem of bronze phenomenon. This phenomenon tends to take place when solubility of the dye in water is reduced or when a hydrogen bond-forming group is introduced into the structure of the dye for the purpose of improving resistance to water, light or gas. Since the bronze phenomenon causes reflection or scattering of light, the recorded image suffers not only reduction of optical density but also serious change in hue from desired hue and loss of transparency. Thus, depression of the bronze phenomenon is one of important factors required for the ink for use in inkjet recording.
[0006] As methods for depressing the bronze phenomenon, there have so far been known a method of adding a specific, nitrogen-containing compound (see, for example, JP-A-6-25575, JP-A-6-228476, JP-A-6-248212, JP-A-7-228810, JP-A-7-268261, JP-A-9-12946 and JP-A-9-12949), a method of adding a specific, hetero ring compound (see, for example, JP-A-8-259865, JP-A-2004-149612 and JP-A-2004-149613), a method of adding a specific titanium-containing compound (see, for example, JP-A-8-337745), and a method of adding an alkali metal ion (see, for example, JP-A-7-26178). However, although the bronze phenomenon can be depressed by adding these additives, the amounts thereof tend to become large due to their insufficient effects, or there arises a problem with respect to storage stability. Thus, the methods can deteriorate various performances of the ink and the quality of recorded images. For example, in the case of adding an alkanolamine to the ink, pH of the ink becomes as high as 11 or more even when it is added in only a small amount. It is described in JP-A-8-259865 that an ink having such a high pH adversely affects the nozzle and, in addition, lacks safety in the case when it is accidentally touched by a human body, and reduces quality of printed letters and resistance to water of recorded images.
[0007] Although various effects can be obtained by using the additives, it has been difficult to use the additives of the related art with maintaining various performances. In particular, in the case where it is necessary to take solubility and association of a dye into consideration, it can be seen that selection of kind and amount of the additive are difficult. Also, in the case of using an ionic additive, influences of the counter ion thereof must be taken into consideration as well. Therefore, it has been desired to introduce a method of essentially depressing the bronze phenomenon by designing a molecule of the additive based on a novel idea.
[0008] Further, as a method for depressing bronze phenomenon caused by a cyan dye or the like, there has been known a method of using a compound having a carboxyl group (EP-A-1357158). However, the compounds serve to depress bronze phenomenon with respect to dyes of a comparatively longer wavelength such as cyan dyes and, as to bronze phenomenon caused by the yellow dye, nothing is described therein.
SUMMARY OF THE INVENTION
[0009] Objects of an illustrative, non-limiting embodiment of the invention are:
(1) to provide a novel ink composition which has an bsorption characteristic excellent in reproducing a yellow color as one of the three primary colors and a sufficient fastness against light, heat, humidity and active gases in the environment and which does not cause bronze phenomenon; (2) to provide an ink composition for use in inkjet recording and an inkjet recording method which can form, by using particularly a yellow azo dye, an image having a good hue, a high fastness against light and active gases in the environment, particularly, an ozone gas, having an excellent water resistance and not causing the bronze phenomenon; and (3) to provide a method of providing an image-recorded product not suffering bronze phenomenon and a method of preventing the bronze phenomenon, by utilizing the above-mentioned inkjet recording method.
[0013] The above-described object of the invention can be accomplished by the following constitutions.
(1) An ink composition containing: water; a yellow dye having an oxidation potential nobler than 1.0 V; and at least one compound of an aromatic compound (an aromatic compound having either a hetero ring or a hydrocarbon ring), an aliphatic compound and a salt thereof, the at least one compound having at least one of a carboxyl group, a sulfo group and a phosphoric acid group. The at least one compound is sometimes referred to as “acid group-containing compound”. (2) The ink composition as described in (1), wherein the acid group-containing compound is at least one of an aromatic compound and a salt thereof. (3) The ink composition as described in (1) or (2), wherein the acid group-containing compound has a carboxyl group. (4) The ink composition as described in any one of (1) to (3), wherein the acid group-containing compound is at least one of pyridine-2-carboxylic acid, pyridine-3-carboxylic acid, pyridine-4-carboxylic acid and a salt thereof (5) The ink composition as described in any one of (1) to (4), wherein the acid group-containing compound is at least one of pyridine-2-carboxylic acid and a salt thereof (6) The ink composition as described in any one of (1) to (5), wherein the yellow dye is a compound represented by formula (1):
wherein R 1 and R 2 each represents a monovalent group, Z represents a nitrogen atom, an oxygen atom, a sulfur atom or a carbon atom to which a monovalent group is bound, and M represents a hydrogen atom or a cation, provided that two azo groups exist in the molecule.
(7) The ink composition as described in any one of (1) to (6), which has the acid group-containing compound in a content of from 0.1 to 6% by weight based on the total weight of the ink composition. (8) The ink composition as described in any one of (1) to (7), which has a ratio by weight of the acid group-containing compound: the yellow dye of 0.1:1.0 to 6.0:1.0. (9) The ink composition as described in any one of (1) to (8), which further contains an acetylene glycol-based surfactant. (10) The ink composition as described in (9), which has the acetylene glycol-based surfactant in a content of from 0.1 to 5% by weight based on the total weight of the ink composition. (11) The ink composition as described in any one of (1) to (10), which further contains a glycol ether-based penetration-accelerating agent. (12) The ink composition as described in any one of (1) to (11), which further contains at least one of glycerin and triethylene glycol. (13) The ink composition as described in any one of (1) to (12), which further contains urea. (14) The ink composition as described in any one of (1) to (13), which further contains triethanolamine. (15) The ink composition as described in any one of (1) to (14), which further contains an antiseptic. (16) The ink composition as described in any one of (1) to (15), which has a pH of from 7 to 9. (17) An ink set containing an ink composition described in any one of (1) to (16). (18) An inkjet recording method including using an ink composition described in any one of (1) to (16) or an ink set described in (17). (19) The inkjet recording method as described in (18), wherein an inkjet head forming an ink droplet by mechanical deformation of an electrostrictive strain element is used. (20) The inkjet recording method as described in (18) or (19), which includes ejecting a liquid droplet of the ink composition to deposit the liquid droplet on a recording medium. (21) An inkjet recorded product, which is recorded by employing the inkjet recording method described in any one of (18) to (20). (22) A method for avoiding bronze phenomenon in inkjet recording using an ink composition containing a yellow dye, which includes using an aromatic compound, aliphatic compound and/or the salt thereof having at least one of carboxyl group, sulfo group and phosphoric acid group.
[0036] The invention provides an ink composition (preferably an ink composition for use in inkjet recording) which is excellent in color-reproducing properties and which can form a yellow image having enough fastness against light, heat, humidity and active gases in the environment and, further, an inkjet-recorded product and an inkjet recording method which prevent bronze phenomenon of an image, and a method for preventing the bronze phenomenon of an image.
DETAILED DESCRIPTION OF THE INVENTION
[0037] Exemplary embodiments of the invention will be described in detail below.
[0000] (Yellow Dyes)
[0038] Yellow dyes useful for the invention are described in detail below.
[0039] As the yellow dye to be used in the invention, dyes having an oxidation potential nobler than 1.0 V (vs SCE) are preferred, dyes having an oxidation potential nobler than 1.1 V (vs SCE) are more preferred, and dyes having an oxidation potential nobler than 1.2 V (vs SCE) are particularly preferred, in view of fastness against light, heat and an ozone gas.
[0040] The oxidation potential (E ox ) can easily be measured by those skilled in the art. This method is described in, for example, New Instrumental Methods in Electrochemistry , written by Delahay (published by Interscience Publishers Co. in 1954), Electrochemical Methods , written by J. Bard, et al. (published by John Wiley & Sons Co. in 1980), and Denki Kagaku Sokuteiho , written by Akira Fujishima, et al. (published by Gihodo Shuppansha in 1984).
[0041] Specifically, the oxidation potential is measured in terms of the value versus SCE (saturated calomel electrode) by dissolving a test sample in a solvent such as dimethylformamide or acetonitrile containing a supporting electrolyte such as sodium perchlorate or tetrapropylammonium perchlorate in a concentration of from 1×10 −2 to 1×10 −6 mol/L (liter) and employing various voltammetry methods (polarography using a dropping mercury electrode, cyclic voltammetry and a method of using a rotating disc electrode). In some cases, the thus-obtained values deviate by about several ten mV due to the influence of liquid potential difference or liquid resistance of the sample solution. However, reproducibility of the potential can be ensured by using a standard sample (such as hydroquinone).
[0042] Additionally, in the invention, in order to unambiguously specify the potential, a value (vs SCE) measured in N,N-dimethylformamide containing a supporting electrolyte of tetrapropylammonium perchlorate in a concentration of 0.1 mol·dm −3 (dye concentration: 10 −3 mol/L) using SCE (saturated calomel electrode) as a reference electrode, a graphite electrode as a working electrode and a platinum electrode as an opposite electrode is taken as the oxidation potential of a dye.
[0043] The value of E ox represents easiness with which an electron moves from a sample to an electrode, and a larger value (oxidation potential being nobler) represents that an electron moves from a sample to an electrode with less easiness or, in other words, that the sample is difficult to oxidize. As to relation with structure of a compound, oxidation potential of the compound is made nobler by introducing an electron attractive group, whereas oxidation potential thereof is made less noble. In the invention, in order to reduce reactivity with ozone which functions as an electrophilic agent, it is desirable to introduce an electron attractive group into a yellow dye skeleton to make nobler the oxidation potential of the dye.
[0044] Also, it is preferred for the dyes to be used in the invention to have a good fastness and a good hue. In the case of using in a yellow-colored ink composition (yellow ink), it is particularly preferred for the dye to have a sharp reduction of absorption on the longer wavelength side in the absorption spectrum. Thus, yellow dyes having λ max in the range of from 390 nm to 470 nm and the ratio of the absorbance at λ max +70 nm, or I(λ max +70 nm), to the absorbance at λ max , or I(λ max ), i.e., I(λ max +70 nm)/I(λ max ) is 0.20 or less than that are preferred, with the ratio being more preferably 0.15 or less, still more preferably 0.10 or less. Additionally, the absorption wavelength and the absorbance used in the above definition are the values in a solvent (water or ethyl acetate).
[0045] Dyes to be more preferably used in the invention are those yellow azo dyes which are represented by the foregoing formula (1).
[0046] Detailed descriptions on the formula (1) are given below.
[0047] R 1 , R 2 and a monovalent group represented by Z are the same as the substituents for the aryl group to be described hereinafter.
[0048] The aforesaid dyes have two azo groups within the molecule, and have preferably (1) one group within the molecule which group has two azo group as substituents or (2) two groups each having one azo group. The group having two azo groups and the group having one azo group are preferably hetero ring groups. Examples of the hetero ring which constitutes the hetero ring group include a 5-pyrazolone ring, a 5-aminopyrazole ring, an oxazolone ring, a barbituric acid ring, a pyridone ring, a rhodanine ring, a pyrazolidinedione ring, a pyrazolopyridone ring and a merdramic acid ring. Of these, a 5-pyrazolone ring and a 5-aminopyrazole ring are preferred, with a 5-aminopyrazole being particularly preferred.
[0049] In the invention, M represents a hydrogen atom or a cation. Examples of the cation represented by M include an alkali metal ion and an ammonium or quaternary ammonium ion, with Li, Na, K, NH 4 and NR 4 being preferred (wherein R represents an alkyl group or an aryl group and is the same as the alkyl group or the aryl group to be described hereinafter).
[0050] Of the azo dyes represented by formula (1), those dyes are preferred which are represented by formulae (2), (3) and (4).
[0051] The monovalent groups represented by R 3 and R 4 , respectively, in formula (2) are the same as the substituents for the aryl group to be described hereinafter. Further, preferred examples thereof include an alkyl group, a cycloalkyl group, an aralkyl group, an alkoxy group, an aryl group, an amino group, a carboxyl group (or the salt thereof) and a carbamoyl group, with an alkyl group (preferably a lower alkyl group having from 1 to 5 carbon atoms, such as methyl, ethyl, butyl or t-butyl) being more preferred. Detailed descriptions on these substituents are the same as that for the substituents to be described hereinafter.
[0052] As a hetero ring of a hetero ring group represented by Ar 1 or Ar 2 , a 5-membered or 6-membered ring is preferred, which may further be condensed with other ring. Also, the hetero ring may be an aromatic hetero ring or a non-aromatic hetero ring. Examples thereof include pyridine, pyrazine, pyridazime, quinole, kisoquinoline, quinazoline, cinnoline, phthalazine, quinoxaline, pyrrole, indole, furan, benzofuran, thiophene, benzothiophene, pyrazole, imidazole, benzimidazole, triazole, oxazole, benzoxazole, thiazole, benzothiazole, isothiazole, benzisothiazole, thiadiazole, isoxazole, benzisoxazole, pyrrolidine, piperidine, piperazine, imidazolidine and thiazoline. Of these, aromatic hetero ring groups are preferred. To exemplify preferred examples thereof in the same manner as above, there are illustrated pyridinem pyrazine, pyridazine, pyrazole, imidazole, benzimidazole, triazole, benzoxazole, thiazole, benzothiazole, isothazole, benzisothiazole and thiadiazole. More preferred are imidazole, benzoxazole and thiadiazole, with thiadiazole (preferably 1,3,4-thiadiazole or 1,2,4-thiadiazole) being most preferred. These may have a substituent or substituents, and examples of such substituents are the same as the substituents for an aryl group to be described hereinafter.
[0053] The aryl group represented by Ar 1 or Ar 2 includes substituted or unsubstituted aryl groups. As the substituted or unsubstituted aryl group, aryl groups having from 6 to 30 carbon atoms are preferred. Examples of the substituent for the aryl group include a halogen atom, an alkyl group, a cycloalkyl group, an aralkyl group, an alkenyl group, an alkynyl group, an aryl group, a hetero ring group, a cyano group, a hydroxyl group, a nitro group, a carboxyl group (including a salt form thereof), an alkoxy group, an aryloxy group, a silyloxy group, a hetero ring oxy group, an acyloxy group, a carbamoyloxy group, an alkoxycarbonyloxy group, an aryloxycarbonyloxy group, an amino group (including an anilino group), an acylamino group, an aminocarbonylamino group, an alkocycambonylamino group, an aryloxycarbonylamino group, a sulfamoylamino group, an alkyl- or aryl-sulfonylamino group, a mercapto group, an alkylthio group, an arylthio group, a hetero ring thio group, a sulfamoyl group, a sulfo group (including a salt form thereof), an alkyl- or aryl-sulfinyl group, an alkyl- or aryl-sulfonyl group, an acyl group, an aryloxycarbonyl group, an alkoxycarbonyl group, a carbamoyl group, an imido group, a phosphino group, a phosphinyl group, a phospinyloxy group, a phosphinylamino group and a silyl group.
[0054] As the aryl group represented by Ar 1 and Ar 2 , substituted phenyl groups (the substituent being preferably a carboxyl group or a sulfo group) are more preferred.
[0055] Those dyes are preferred which are represented by the foregoing formula (2) wherein Ar 1 and Ar 2 are represented by formula (A).
[0056] In formula (A), Ra represents a monovalent group. The monovalent group represented by Ra is the same as having been defined with respect to R 1 and R 2 in formula (1), and preferred scopes thereof are also the same as described there. More preferably, Ra represents -L-Ph or -Ph (wherein Ph represents a substituted or unsubstituted phenyl group, with the substituent being the same as the monovalent group represented by R 1 and R 2 , and L represents a divalent linking group and is the same as Ar 3 in formula (3)). Still more preferably, Ra represents —S-Ph or -Ph (wherein Ph represents a substituted or unsubstituted phenyl group).
[0057] The substituents for the aryl group are described in more detail below.
[0058] The halogen atom includes a chlorine atom, a bromine atom and an iodine atom.
[0059] The alkyl group includes a substituted alkyl group and an unsubstituted group. The substituted or unsubstituted alkyl group contains preferably from 1 to 30 carbon atoms. Examples of the substituent include the same ones as those for the aryl group. Among them, a hydroxyl group, an alkoxy group, a cyano group, a halogen atom, a sulfo group (including a salt form thereof) and a carboxyl group (including a salt form thereof) are preferred. Examples of the alkyl group include methyl, ethyl, butyl, t-butyl, n-octyl, eicosyl, 2-chloroethyl, hydroxyethyl, cyanoethyl and 4-sulfobutyl.
[0060] The cycloalkyl group includes a substituted or unsubstituted cycloalkyl group. The substituted or unsubstituted cycloalkyl group is preferably a cycloalkyl group having from 5 to 30 carbon atoms. Examples of the substituent include the same one as the substituents for the aryl group. Examples of the cycloalkyl group include cyclohexyl, cyclopentyl and 4-n-dodecylcyclohexyl.
[0061] The aralkyl group includes a substituted or unsubstituted aralkyl group. The substituted or unsubstituted aralkyl group is preferably an aralkyl group having from 7 to 30 carbon atoms. Examples of the substituent include the same one as the substituents for the aryl group. Examples of the aralkyl group include benzyl and 2-phenethyl.
[0062] The alkenyl group includes a straight, branched or cyclic, substituted or unsubstituted alkenyl group. The alkenyl group is preferably a substituted or unsubstituted alkenyl group having from 2 to 30 carbon atoms, such as vinyl, allyl, prenyl, geranyl, oleyl, 2-cyclopenten-1-yl or 2-cyclohexen-1-yl.
[0063] The alkynyl group is a substituted or unsubstituted alkynyl group having from 2 to 30 carbon atoms, and examples thereof include ethynyl and propargyl.
[0064] The aryl group is a substituted or unsubstituted aryl group having from 6 to 30 carbon atoms, and examples thereof include phenyl, p-tolyl, naphthyl, m-chlorophenyl and o-hexadecanoylaminophenyl.
[0065] The hetero ring group is a monovalent group formed by removing one hydrogen atom from a 5- or 6-membered, substituted or unsubstituted, aromatic or non-aromatic hetero ring compound. More preferably, the hetero ring group is a 5- or 6-membered aromatic hetero ring group having from 3 to 30 carbon atoms. Examples thereof include 2-furyl, 2-thietnyl, 2-pyrimidinyl, 2-benzothiazolyl and morpholino.
[0066] The alkoxy group includes a substituted or unsubstituted alkoxy group. The substituted or unsubstituted alkoxy group is preferably an alkoxy group having from 1 to 30 carbon atoms. Examples of the substituent include the same one as the substituents for the aryl group. Examples of the alkoxy group include methoxy, ethoxy, isopropoxy, n-octyloxy, methoxyethoxy, hydroxyethoxy and 3-carboxypropoxy.
[0067] The aryloxy group is a substituted or unsubstituted aryloxy group containing from 6 to 30 carbon atoms, and examples thereof include phenoxy, 2-methylphenoxy, 4-t-butylphenoxy, 3-nitrophenoxy and 2-tetradecanoylaminophenoxy.
[0068] The silyloxy group is a silyloxy group containing from 3 to 30 carbon atoms, and examples thereof include trimethylsilyloxy and t-butyldimethylsilyloxy.
[0069] The hetero ring oxy group is a substituted or unsubstituted hetero ring oxy group containing from 2 to 30 carbon atoms, and examples thereof include 1-phenyltetrazol-5-oxy and 2-tetrahydropyranyloxy.
[0070] The acyloxy group is a substituted or unsubstituted alkylcarbonyloxy group containing from 2 to 30 carbon atoms or a substituted or unsubstituted aryloxycarbonyl group containing from 6 to 30 carbon atoms, and examples thereof include formyloxy, acetyloxy, pivaloyloxy, stearoyloxy, benzoyloxy and p-methoxyphenylcarbonyloxy.
[0071] The carbamoyloxy group is a substituted or unsubstituted carbamoyloxy group containing from 1 to 30 carbon atoms, and examples thereof include N,N-dimethylcarbamoyloxy, N,N-diethylcarbamoyloxy, morpholinocarbonyloxy, N,N-di-n-octylaminocarbonyloxy and N-n-octylcarbamoyloxy.
[0072] The alkoxycarbonyloxy group is a substituted or unsubstituted alkoxycarbonyloxy group containing from 2 to 30 carbon atoms, and examples thereof include methoxycarbonyloxy, ethoxycarbonyloxy, t-butoxycarbonyloxy and n-octylcarbonyloxy.
[0073] The aryloxycarbonyloxy group is a substituted or unsubstituted aryloxycarbonyloxy group containing from 7 to 30 carbon atoms, and examples thereof include phenoxycarbonyloxy, p-methoxyphenoxycarbonyloxy and p-n-hexadecyloxyphenoxycarbonyloxy.
[0074] The amino group is a substituted or unsubstituted alkylamino group containing from 1 to 30 carbon atoms or a substituted or unsubstituted arylamino group containing from 6 to 30 carbon atoms, and examples thereof include amino, methylamino, dimethylamino, aniline, N-methyl-anilino, diphenylamino, hydroxyethylamino, carboxyethylamino, sulfoethylamino and 3,5-dicarboxyanilino.
[0075] The acylamino group is a formylamino group, a substituted or unsubstituted alkylcarbonylamino group containing from 1 to 30 carbon atoms or a substituted or unsubstituted arylcarbonylamino group containing from 6 to 30 carbon atoms, and examples thereof include formylamino, acetylamino, pivaloylamino, lauroylamino, benzoylamino and 3,4,5-tri-n-octyloxyphenylcarbonylamino.
[0076] The aminocarbonylamino groupo is a substituted or unsubstituted aminocarbonylamino group containing from 1 to 30 carbon atoms, and examples thereof include carbamoylamino, N,N-dimethylaminocarbonylamino, N,N-diethylaminocarbonylamino and morpholinocarbonylamino.
[0077] The alkoxycarbonylamino group is a substituted or unsubstituted alkoxycarbonylamino group containing from 2 to 30 carbon atoms, and examples thereof include methoxycarbonylamino, ethoxycarbonylamino, t-butoxycarbonylamino, n-octadecyloxycarbonylamino and N-methyl-methoxycarbonylamino.
[0078] The aryloxycarbonylamino group is a substituted or unsubstituted aryloxycarbonylamino group containing from 7 to 30 carbon atoms, and examples thereof include phenoxycarbonylamino, p-chlorophenoxycarbonylamino and m-n-octyloxyphenoxycarbonylamino.
[0079] The sulfamoylamino group is a substituted or unsubstituted sulfamoylamino group containing from 0 to 30 carbon atoms, and examples thereof include sulfamoylamino, N,N-dimethylaminosulfonylamino and N-n-octylaminosulfonylamino.
[0080] The alkylsulfonylamino group and aryl-sulfonylamino group are a substituted or unsubstituted alkylsulfonylamino group containing from 1 to 30 carbon atoms and a substituted or unsubstituted arylsulfonylamino group containing from 6 to 30 carbon atoms, respectively, and examples thereof include methylsulfonylamino, butylsulfonylamino, phenylsulfonylamino, 2,3,5-trichlorophenylsulfonylamino and p-methylphenylsulfonylamino.
[0081] The alkylthio group is a substituted or unsubstituted alkylthio group containing from 1 to 30 carbon atoms, and examples thereof include methylthio, ethylthio and n-hexadecylthio.
[0082] The arylthio group is a substituted or unsubstituted arylthio group containing from 6 to 30 carfbon atoms, and examples thereof include phenylthio, p-chlorophenylthio and m-methoxyphenylthio.
[0083] The hetero ring thio group is a substituted or unsubstituted hetero ring thio group containing from 2 to 30 carbon atoms, and examples thereof include 2-benzothiazolylthio and 1-phenyltetrazol-5-ylthio.
[0084] The sulfamoyl group is a substituted or unsubstituted sulfamoyl group containing from 0 to 30 carbon atoms, and examples thereof include N-ethylsulfamoyl, N-(3-dodecyloxypropyl)sulfamoyl, N,N-dimethylsulfamoyl, N-acetylsulfamoyl, N-benzoylsulfamoyl and N-(N′-phenylcarbamoyl)sulfamoyl.
[0085] The alkylsulfinyl group and arylsulfinyl group are a substituted or unsubstituted alkylsulfinyl group containing from 1 to 30 carbon atoms and a substituted or unsubstituted arylsulfinyl group containing from 6 to 30 carbon atoms, respectively, and examples thereof include methylsulfinyl, ethylsulfinyl, phenylsulfinyl and p-methylphenylsulfinyl.
[0086] The alkylsulfonyl group and arylsulfonyl group are a substituted or unsubstituted alkylsulfonyl group containing from 1 to 30 carbon atoms and a substituted or unsubstituted arylsulfonyl group containing from 6 to 30 carbon atoms, respectively, and examples thereof include methylsulfonyl, ethylsulfonyl, phenylsulfonyl and p-methylphenylsulfonyl.
[0087] The acyl group is a formyl group, a substituted or unsubstituted alkylcarbonyl group containing from 2 to 30 carbon atoms, a substituted or unsubstituted arylcarbonyl group containing from 7 to 30 carbon atoms or a substituted or unsubstituted hetero ring carbonyl group containing from 4 to 30 carbon atoms and being connected through a carbonyl group, and examples thereof include acetyl, pivaloyl, 2-chloroacetyl, stearoyl, benzoyl, p-n-octyloxyphenylcarbonyl, 2-pyridylcarbonyl and 2-furylcarbonyl.
[0088] The aryloxycarbonyl group is a substituted or unsubstituted aryloxycarbonyl group containing from 7 to 30 carbon atoms, and examples thereof include phenoxycarbonyl, o-chlorophenoxycarbonyl, m-nitrophenoxycarbonyl and p-t-butylphenoxycarbonyl.
[0089] The alkoxycarbonyl group is a substituted or unsubstituted alkoxycarbonyl group containing from 2 to 30 carbon atoms, and examples thereof include methoxycarbonyl, ethoxycarbonyl, t-butoxycarbonyl and n-octadecylcarbonyl.
[0090] The carbamoyl group is a substituted or unsubstituted carbamoyl group containing from 1 to 30 carbon atoms, and examples thereof include carbamoyl, N-methylcarbamoyl, N,N-dimethylcarbamoyl, N,N-di-n-octylcarbamoyl and N-(methylsulfonyl)carbamoyl.
[0091] The phosphino group is a substituteds or unsubstituted phosphino group containing from 2 to 30 carbon atoms, and examples thereof include dimethylphosphino, diphenylphosphino and methylphenoxyphosphino.
[0092] The phosphinyl group is a substituted or unsubstituted phosphinyl group containing from 2 to 30 carbon atoms, and examples thereof include phosphinyl, dioctyloxyphosphinyl and diethoxyphosphinyl.
[0093] The phosphinyloxy group is a substituted or unsubstituted phosphinyloxy group containing from 2 to 30 carbon atoms, and examples thereof include diphenoxyphosphinyloxy and dioctyloxyphosphinyloxy.
[0094] The phosphinylamino group is a substituted or unsubstituted phosphinylamino group containing from 2 to 30 carbon atoms, and examples thereof include dimethoxyphosphinylamino and dimethylaminophosphinylamino.
[0095] The silyl group is a substituted or unsubstituted silyl group containing from 3 to 30 carbon atoms, and examples thereof include trimethylsinyl, t-butyldimethylsinyl and phenyldimethylsilyl.
[0096] Of the substituents of the above-described aryl group, those which have a hydrogen atom may further be substituted by replacing the hydrogen atom by the above-mentioned group. Examples of such functional group include an alkylcarbonylaminosulfonyl group, an arylcarbonylaminosulfonyl group, an alkylsulfonylaminocarbonyl group and an arylsulfonylaminocarbonyl group. Specific examples thereof include methylsulfonylaminocarbonyl, p-methylphenylsulfonylaminocarbonyl, acetylaminosulfonyl and benzoylaminosulfonyl.
[0097] Formula (3) is described in detail below. The monovalent group represented by R 5 and R 6 is the same as the monovalent group represented by R 3 and R 4 in formula (2). The monovalent group represented by R 7 and R 8 is the same as the aforesaid substituent for the aryl group. Further, each of R 7 and R 8 is preferably a halogen atom, OM (wherein M represents a hydrogen atom or cation), an alkoxy group, an alkylthio group, an arylthio group, an amino group or a hetero ring group. Substituents for these are the same as described hereinbefore.
[0098] The divalent linking group represented by A 3 is preferably an alkylene group (e.g., methylene, ethylene, propylene, butylenes or pentylene), an alkenylene group (e.g., ethenylene or propenylene), an alkynylene group (e.g., ethynylene or propynylene), an arylene group (e.g., phenylene or naphthylnene), a divalent hetero ring group (e.g., 6-chloro-1,3,5-triazin-2,4-diyl, pyrimidin-2,4-diyl, quinoxalin-2,3-diyl or pyridazin-3,6-diyl), —O—, —CO—, —NR— (wherein R represents a hydrogen atom, an alkyl group or an aryl group), —S—, —SO 2 —, —SO— or a combination thereof (e.g., —NHCH 2 CH 2 NH— or —NHCONH—).
[0099] The alkylene group, alkenylene group, alkynylene group, arylene group, divalent hetero ring group, and alkyl or aryl group of R may have a substituent or substituents. Examples of the substituent are the same as the substituents for the aryl group. The alkyl and aryl groups of R are the same as defined hereinbefore.
[0100] More preferably, the linking group is an alkylene group containing 10 or less carbon atoms, an alkenylene group containing 10 or less carbon atoms, an alkynylene group containing 10 or less carbon atoms, an arylene group containing from 6 to 10 carbon atoms, —S—, —SO—, —SO 2 — or a combination thereof (e.g., —SCH 2 CH 2 S— or —SCH 2 CH 2 CH 2 S—).
[0101] The total number of carbon atoms of the divalent linking group is preferably from 0 to 50, more preferably from 0 to 30, most preferably from 0 to 10.
[0102] Formula (4) is described in detail below. The monovalent group represented by R 9 and R 10 is the same as the monovalent group represented by R 3 and R 4 in formula (2). The aryl group and the hetero ring group represented by Ar 4 and Ar 5 are the same as the aryl group and the hetero ring group represented by Ar 1 and Ar 2 of formula (2), with the hetero ring group being preferred. The divalent linking group represented by Ar 6 is the same as the divalent linking group of Ar 3 in formula (3).
[0103] In the invention, in the case where the compounds represented by formulae (1), (2), (3) and (4) are required to have hydrophilicity, it is preferred for the compounds to have two or more hydrophilic groups within the molecule, more preferably from 2 to 10 hydrophilic groups, particularly preferably from 3 to 6 carbon atoms. However, in the case where water is not used as a solvent, the compounds may not have the hydrophilic group.
[0104] As the hydrophilic group, any hydrophilic group may be used as long as it is an ionic dissociative group. Specific examples thereof include a sulfo group, a carboxyl group (including the salt thereof), a hydroxyl group (including the salt thereof), a phosphono group (including the salt thereof) and a quaternary ammonium group, with a sulfo group, a carboxyl group and a hydroxyl group (including the salt thereof) being preferred.
[0105] In view of color reproducibility, dyes represented by the foregoing formulae (1), (2), (3) and (4) have the maximum absorption wavelength (λmax) of from 380 to 490 nm in H 2 O, preferably from 400 to 480 nm, particularly preferably from 420 to 460 nm.
[0106] Specific examples of the dyes represented by the foregoing formulae (1), (2), (3) and (4) (illustrative dyes 1 to 39) are shown below which, however, are not construed to limit the dyes of the invention in any way.
Dye Ar Dye Ar 1 8 2 9 3 10 4 11 5 12 6 13 7 Dye R Ar 14 ONa —SC 2 H 4 S— 15 ONa —SC 3 H 6 S— 16 ONa 17 ONa 18 ONa 19 ONa 20 —SC 2 H 4 S— 21 —NHC 2 H 4 SO 3 Na —SC 2 H 4 S— 22 —N(CH 2 COONa) 2 —SC 2 H 4 S— 23 —N(C 4 H 9 ) 2 —SC 2 H 4 S— 24 —NH 2 —SC 2 H 4 S— 25 —SC 3 H 6 SO 3 Na —SC 2 H 4 S— 26 —NHC 2 H 4 SO 3 Na 27 —NHC 2 H 4 SO 3 Na Dye Ar 28 29 30 31 32 33 —NHC 2 H 4 NH— Dye Ar 34 —SC 2 H 4 S— 35 —SC 3 H 6 S— 36 37 38 39 Dye Ar 40 41 42 43 44 45 46 47 48 Dye Ar 49 50 51 52 Dye R Ar 53 t-C 4 H 9 54 t-C 4 H 9 55 Ph 56 CH 3 57 t-C 4 H 9 Dye R Ar 58 t-C 4 H 9 59 t-C 4 H 9 60 t-C 4 H 9 Dye R Ar 61 t-C 4 H 9 62 t-C 4 H 9 63 t-C 4 H 9
[0107] As a typical example, a method for synthesizing Dye 1 is described below. Each step in the Synthesis Example can be conducted according to a known method (JP-A-2001-279145, JP-A-2003-277661, JP-A-2003-277662 and JP-A-2004-83903 being able to be referred to).
(1) 18.5 g of NaHCO 3 and 185 ml of H 2 O were heated to 40° C., and a solution of 18.4 g of compound a in 48 ml of acetone was added thereto, followed by stirring the resulting mixture for 1 hour. After concentrating acetone, 40 g of hydrazine was added thereto, and the mixture was stirred at room temperature for 3 hours. Crystals precipitated were collected by filtration to obtain 14 g of compound b. (2) To a mixture of 10.5 g of compound b, 20 g of compound c and 330 ml of H 2 O was added 10 ml of 1N-NaOH, followed by heating for 3 hours. The reaction mixture was filtered, and the filtrate was rendered acidic with acetic acid. Crystals precipitated were collected by filtration to obtain 4 g of compound d. (3) 15 g of compound e was diazotized and added to a mixture of 3 g of compound d, 100 ml of MeOH and 16 g of AcOK at 5° C. Crystals precipitated were collected by filtration and subjected to column chromatography using Sephadex to obtain 4.9 g of Dye 1.
[0111] λ max 451.7 nm (H 2 O); ε: 5.88×10 4 (dm 3 ·cm/mol)
[0112] Other dyes can be synthesized in the same manner.
[0000] (Synthesis of Dye 20)
[0113] Synthesis example of Dye 20 is shown below. Dye 20 can be synthesized in the same manner by applying the method of synthesizing Dye 1.
[0114] Synthesis of Compound h
[0115] 22.6 g of compound g was added to a mixture of 9.1 g of compound f and 27 ml of N,N-dimethylacetamide, and reaction was conducted at room temperature for 2 hours, followed by adding methanol thereto. Crystals precipitated were collected by filtration to obtain 23 g of compound h.
[0000] Synthesis of Compound i
[0116] A mixture of 23 g of compound h, 31 ml of CF 3 COOH and 6.2 g of thiourea were stirred at 120° C. for 2 hours, followed by adding thereto H 2 O and EtOH. Crystals precipitated were collected by filtration to obtain 14 g of compound i.
[0000] Synthesis of Compound j
[0117] 80 ml of 10% KOH was added to a solution of 14 g of compound i in 150 ml of water, followed by stirring at room temperature for 2 hours. 32 ml of concentrated hydrochloric acid was added thereto, and crystals precipitated were collected by filtration to obtain 14 g of compo9und j.
[0000] Synthesis of Dye 40
[0118] 5.5 g of compound j was diazotized with 0.9 g of NaNO 2 , and was added to a mixture of an intermediate d, 10 ml of dimethylformamide and 50 ml of methanol at a temperature of 10° C. or lower than that. Crystals precipitated were collected by filtration, rendered alkaline with 5% KOH and subjected to column chromatography using Sephadex to obtain 3.4 g of Dye 40.
[0119] λ max 456.8 nm (H 2 O); ε: 6.10×10 4 (dm 3 ·cm/mol)
[0120] Synthesis of Compound b1
[0121] 18.5 g of NaHCO 3 and 185 ml of H 2 O were heated to 40° C., and a solution of 18.4 g of compound a1 (product of Tokyo Kasei) in 48 ml of acetone was added thereto, followed by stirring the resulting mixture for 1 hour. After concentrating acetone, 40 g of hydrazine was added thereto, and the mixture was stirred at room temperature for 3 hours. Crystals precipitated were collected by filtration to obtain 14 g of compound b1 (m.p.>300° C.).
[0000] Syntiesis of Compound c1
[0122] To a mixture of 10.5 g of compound b1, 20 g of pivaloylacetonitrile (product of Tokyo Kasei) and 330 ml of H 2 O was added 10 ml of 1N-NaOH, followed by heating for 3 hours. The reaction mixture was filtered, and the filtrate was rendered acidic with acetic acid. Crystals precipitated were collected by filtration to obtain 4 g of compound c1 (m.p.=233 to 235° C.). 1 H-NMR (DMSO-d 6 ),σ value (TMS standard):1.2-1.3 (18H, s)
[0000] Synthesis of Compound e1
[0123] 90.57 g of compound d1 was suspended in 500 ml of H 2 O and, after adding thereto 130 ml of concentrated hydrochloric acid, the mixture was cooled till the inside temperature reached 5° C. or lower than that. Subsequently, a solution of 36.23 g of sodium nitrite in 70 ml of water was dropwise added thereto within the inside temperature of from 4 to 6° C., followed by stirring for 30 minutes at the inside temperature of 35° C. or lower than that. Then, a mixture of 159 g of sodium sulfite and 636 ml of H 2 O were added thereto with keeping the inside temperature at 20° C. or lower than that and, further, 250 ml of concentrated hydrochloric acid was added thereto at the inside temperature of 25° C. Subsequently, the mixture was stirred for 1 hour at the inside temperature of 90° C. and, after cooling the mixture to room temperature in terms of the inside temperature, the product was washed with 200 ml of water and air dried to obtain 80.0 g of compound e1.
[0000] Synthesis of Compound f1
[0124] 28 ml of triethylamine was dropwise added to a suspension of 23.3 g of compound e1 in 209 ml of ethanol, and then 12.2 g of ethoxymethylenemalononitrile (product of ALDRICH) was added thereto by portions, followed by refluxing for 3 hours. After cooling, the product was filtered, washed with 400 ml of isopropyl alcohol, and dried to obtain 23.57 g of compound f1.
[0000] Synthesis of Dye 62
[0125] 5.4 g of compound f1 was dissolved in 43 ml of phosphoric acid at room temperature and, while stirring at an inside temperature of 0° C., 3 ml of isoamyl nitrite (product of Tokyo Kasei) was dropwise adde thereto and, after stirring for 10 minutes at the same temperature, dropwise added to a suspension of 3 g of compound c1 in 100 ml of methanol at an inside temperature of −3 to 5° C. After stirring at the same temperature for 20 minutes, the reaction solution was poured into 500 ml of H 2 O and, after stirring at room temperature for 10 minutes, crystals precipitated were collected by filtration, washed with H 2 O and air dried to obtain 5.5 g of crude crystals of Dye 62. After preparing a 10 wt % aqueous solution of the thus-obtained crude crystals (at 25° C.; PH: about 8.3.adjusted with a KOH aqueous solution), it was purified through gel column chromatography (H 2 O; Sephadex LH-20; Amersham Biosciences) to obtain 2.8 g of Dye 62.
[0126] λ max 436 nm (H 2 O); ε: 3.38×10 4 (dm 3 ·cm/mol)
[0127] The other dyes can be synthesized in the same manner.
[0128] The aromatic compound, aliphatic compound and/or the salt thereof, which have at least one of carboxyl group, sulfo group and phosphoric acid group, is described below. In the invention, these compounds are generically referred to as “acid group-containing compound”.
[0129] In the invention, the term “aromatic compound” as used herein means an aromatic compound having either a hetero ring or a hydrocarbon ring.
[0130] The aromatic compound and the aliphatic compound are preferably represented by formula (ACI):
Z—(X)n
wherein Z represents an aromatic group or an aliphatic group, X independently represents a member selected from among a carboxyl group (—COOH), a sulfo group (—SO 3 H) and a phosphoric acid group (—OP(O)(OH) 2 ), which may form a salt form, and n represents an integer of from 1 to 6, preferably from 1 to 4. When n represents 2 or more, plural Xs may be the same or different from each other. The counter cation for the salt is not particularly limited, and examples thereof include an alkali metal, ammonium and an organic cation (e.g., tetramethylammonium, guanidium or pyridinium). Of these, an alkali metal and ammonium are preferred, and lithium, potassium, sodium and ammonium are more preferred, with lithium and ammonium being most preferred.
[0131] The aromatic group represented by Z may be a group wherein a plurality of aromatic groups are linked to each other through a linking group, and these aromatic rings may further have an aromatic group and/or an aliphatic group as a substituent. The aliphatic group represented by Z may be a group wherein a plurality of aliphatic groups are linked to each other through a linking group, and the aliphatic moiety thereof may further have an aliphatic group as a substituent.
[0132] The aromatic group may be a monocyclic aromatic group or a polycyclic aromatic group, and preferred examples thereof include a phenyl group, a pyridyl group, a pyridonyl group, a thiophenyl group and a furanyl group, which may have a substituent.
[0133] Preferred examples of the polycyclic aromatic group include a naphthyl group, a quinolyl group, an indolinyl group, a benzothienyl group and a benzofuranyl group, which may have a substituent.
[0134] Examples of the linking group include —O—, —S—, —NH—, —CO—, —CH 2 —, —CH(CH 3 )—, —CH═CH— and a group wherein a plurality of these are combined.
[0135] Examples of the substituent for the aromatic group and the aliphatic group are the same as the aforesaid substituents for the aryl group. As the position at which X is bound, X may be bound to the aromatic group or the aliphatic group directly or to the substituent.
[0136] Specific examples of the compound represented by formula (AC1) are described below. Examples of the aliphatic group-containing compound include acetic acid, propionic acid, butyric acid, isobutyric acid, n-valeric acid, lauric acid (dodecanoic acid), hexahydrobenzoic acid (cyclohexanecarboxylic acid); oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, azelaic acid, 1,2,3,4-butanetetracarboxylic acid, ethylenediaminetetraacetic acid; maleic acid, fumaric acid, citraconic acid; ascorbic acid, and citric acid. Examples of the aromatic group-containing compound include pyromellitic acid, trimesic acid, trimellitic acid, sulfophthalic acid, phthalic acid, terephthalic acid, p-mercaptobenzoic acid, thiosalicylic acid, sulfosalicylic acid,
picolinic acid (pyridine-2-carboxylic acid), nicotinic acid (pyridine-3-carboxylic acid), isonicotinic acid (pyridine-4-carboxylic acid), quinolinic acid, lutidinic acid, isocinchomeronic acid and dipicolinic acid. Further, colorless, water-soluble, plane compounds having more than 10 non-localized π electrons per molecule which are described in JP-A-2003-307823 can be used as well.
[0137] Of the above-described acid group-containing compound, aromatic compounds (and/or salts thereof) are preferred. Further, aromatic compounds having at least one hetero atom in the ring structure are more preferred. As the hetero atom, nitrogen atom is more preferred. Of the carboxyl group, sulfo group and phosphoric acid group, the carboxyl group is more preferred. These compounds are preferably substantially colorless. The term “substantially colorless” as used herein means that an absorption peak on the longer wavelength side exists at a wavelength (λ max ) of 350 nm or less and the molar extinction coefficient is 10,000 or less. Specifically, picolinic acid (pyridine-2-carboxylic acid), pyridine-3-carboxylic acid and pyridine-4-carboxylic acid are preferred, with pyridine-2-carboxylic acid being particularly preferred.
[0138] The acid group-containing compound is contained in the ink composition in a content (total amount of acid-group-containing compounds) of preferably from 0.01 to 60% by weight, more preferably from 0.05 to 10% by weight, still more preferably from 0.1 to 6% by weight.
[0000] (Ink Composition)
[0139] A preferred ink composition of the invention (hereinafter “ink composition” being in some cases abbreviated as “ink”) is an ink containing at least one dye represented by formula (1).
[0140] The ink of the invention permits incorporation of a medium. In the case where a solvent is used as a medium, the ink is particularly suited as an ink for use in inkjet recording. The ink of the invention can abe prepared by using as a medium an oloeophilic medium or an aqueous medium and dissolving and/or dispersing therein the dye of the invention. Preferably, an aqueous medium is used.
[0141] In the case of dispersing the dye to be used in the invention in an aqueous medium, it is preferred to disperse colored fine particles containing a dye and an oil-soluble polymer in an aqueous medium as described in JP-A-11-286637, JP-A-2001-240763, JP-A-2001-262039 and JP-A-2001-247788 or to disperse the dye of the invention dissolved in a high-boiling organic solvent in an aqueous medium as described in JP-A-2001-262018, JP-A-2001-240763, JP-A-2001-335734 and JP-A-2002-80772. As to specific method for dispersing the dye to be used in the invention in the aqueous medium, oil-soluble polymers to be used, high-boiling organic solvents, additives and the amounts thereof to be used, those which are described in the above-mentioned patent documents can preferably be used. Alternatively, the azo dyes may be dispersed as solid in a state of fine particles. Upon dispersion, a dispersant or a surfactant can be used. As a dispersing apparatus, a simple-structured stirrer, an impeller-stirring system, an in-line stirring system, a mill system (e.g., colloid mill, ball mill, sand mill, attritor, roll mill or agitator mill), an ultrasonic wave system and a high-pressure emulsification system (high-pressure homogenizer; specific commercially available apparatus: Gaulin homogenizer, micro-fluidizer or DeBEE 2000) may be used. As to the method for preparing the ink for inkjet recording, detailed descriptions are given in JP-A-5-148436, JP-A-5-295312, JP-A-7-97541, JP-A-7-82515, JP-A-7-118584, JP-A-11-286637 and JP-A-2001-271003 as well as in the aforesaid patent documents, and can be utilized in preparing the ink of the invention for inkjet recording.
[0142] As the aqueous medium, a mixture containing water as a major component and containing, as needed, a water-miscible organic solvent can be used. Examples of the water-miscible organic solvent include alcohols (e.g., methanol, ethanol, propanol, isopropanol, butanol, isobutanol, sec-butanol, t-butanol, pentanol, hexanol, cyclohexanol and benzyl alcohol), polyhydric alcohols (e.g., ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, polypropylene glycol, butylenes glycol, hexanediol, pentanediol, glycerin, hexanetriol and thiodiglycol), glycol derivatives (e.g., ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monobutyl ether, dipropylene glycol monomethyl ether, triethylene glycol monomethyl ether, ethylene glycol diacetate, ethylene glycol monomethyl ether acetate, triethylene glycol monoethyl ether and ethylene glycol monophenyl ether), amines (e.g., ethanolamine, diethanolamine, triethanolamine, N-methyldiethanolamine, N-ethyldiethanolamine, morpholine, N-ethylmorpholine, ethylenediamine, diethylenetriamine, triethylenetetramine, polyethyoleneimine and tetramethylpropylenediamine) and other polar solvents (e.g., formamide, N,N-dimethylformamide, N,N-dimethylacetamide, dimethylsulfoxide, sulfolane, 2-pyrrolidone, N-methyl-2-pyrrolidone, N-vinyl-2-pyrrolidone, 2-oxazolidone, 1,3-dimethyl-2-imidazolidinone, acetonitrile and acetone). Additionally, the water-miscible organic solvents may be used in combination of two or more thereof. The water-miscible organic solvents are materials which function as anti-drying agents for the ink for use in inkjet recording, penetration accelerating agents and wetting agents.
[0143] The dye represented by formula (1) to be used in the invention is incorporated in an amount of preferably from 0.1 to 20 parts by weight, more preferably from 0.2 to 10 parts by weight, still more preferably from 0.5 to 9 parts by weight, in 100 parts by weight of the ink of the invention for use in inkj et recording. Also, in the ink of the invention for use in inkjet recording, other dyes may be used in combination with the dye represented by formula (1). In the case of using two or more dyes in combination, the total amount of the dyes is preferably within the above-described scope.
[0144] In the ink composition, the acid group-containing compound (the total amount of acid group-containing compounds): the yellow dye by weight is preferably from 0.1:1.0 to 6.0:1.0, more preferably from 0.5:1.0 to 3.0:1.0.
[0145] In the ink composition for use in inkjet recording obtained by the invention, additives such as an anti-drying agent (wetting agent) for preventing clogging of a nozzle for jetting the ink due to drying, a penetration accelerating agent for well penetrating the ink into paper, a UV ray absorbent, an antioxidant, an anti-foaming agent, a viscosity-adjusting agent, a surface tension-adjusting agent, a dispersing agent, a dispersion-stabilizing agent, an antifungal agent, a rust inhibitor and a pH-adjusting agent may properly be selected and used in a proper amount.
[0146] As the anti-drying agent (wetting agent) to be used in the invention, water-soluble organic solvents having a vapor pressure lower than that of water are preferred. Specific examples thereof include polyhydric alcohols represented by ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, thiodiglycol, dithidiglycol, 2-methyl-1,3-propanediol, 1,2,6-hexanetriol, acetylene glycol derivatives, glycerin and trimethylolpropane; polyhydric alcohol lower alkyl ethers such as ethylene glycol monomethyl (or ethyl) ether, diethylene glycol monomethyl (or ethyl) ether, triethylene glycol monoethyl (or butyl) ether; hetero ring compounds such as 2-pyrrolidone, N-methyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone and N-ethylmorpholine; suslfur-containing compounds such as sulfolane, dimethylsulfoxide and 3-sulfolene; multi-functional compounds such as diacetone alcohol and diethanolamine; and urea derivatives (urea, etc.). Of these, urea, glycerin and triethylene glycol are more preferred. The anti-drying agents may be used independently or in combination of two or more thereof. These anti-drying agents are incorporated in the ink in an amount of from 0.5 to 50% by weight, preferably from 10 to 50% by weight.
[0147] As the penetration accelerating agent to be used in the invention, alcohols such as ethanol, isopropanol, butanol, di(tri)ethylene glycol monobutyl ether and 1,2-hexanediol; sodium laurylsulfate and sodium oleate; and nonionic surfactants may be used.
[0148] In the invention, glycol ether-based penetration accelerating agents such as diethylene glycol monobutyl ether and triethylene glycol monobutyl ether are preferably used.
[0149] Incorporation of them in the ink in a content of from 10 to 30% by weight provides sufficient effects, and they are preferably used in an addition amount within the range of not causing blurring of printed letters and print-through troubles.
[0150] As UV ray absorbents to be used in the invention for improving preservability of image, there may be used benzotriazole-based compounds described in JP-A-58-185677, JP-A-61-190537, JP-A-2-782, JP-A-5-197075 and JP-A-9-34057; benzophenone-based compounds described in JP-A-46-2784, JP-A-5-194483 and U.S. Pat. No. 3,214,463; cinnamic acid-based compounds described in JP-B-48-30492, JP-B-56-21141 and JP-A-10-88106; triazine-based compounds described in JP-A-4-298503, JP-A-8-53427, JP-A-8-239368, JP-A-10-182621 and JP-T-8-501291 (the term “JP-T” as used herein means a published Japanese translation of a PCT patent application); compounds described in Research Disclosure No.24239; and compounds which absorb UV rays to emit fluorescence, represented by stilbene-based compounds and benzoxazole-based compounds, so-called fluorescent brightening agents.
[0151] In the invention, as the antioxidant to be used for improving preservability of image, various organic and metal complex-based anti-fading agents may be used. Examples of the organic anti-fading agents include hydroquinones, alkoxyphenols, dialkoxyphenols, phenols, anilines, amines, indanes, chromans, alkoxyanilines and hetero rings, and examples of metal complexes include nickel complexes and zinc complexes. More specifically, compounds described in patents cited in Research Disclosure, No.17643, VII-I to J, ibid., No.15162, ibid., No.18716, p. 650, left column, ibid., No.36544, p. 527, ibid., No.307105, p. 872 and ibid., No.15162 and compounds included by the general formulae for typical compounds described in JP-A-62-215272, pp. 127-137 can be used.
[0152] The anti-foaming agents to be used in the invention are copolymers between dimethylpolysiloxane and polyalkylene oxide and include pendant type, terminal group-modified type and ABN type, with pentant type being preferred. Examples of the copolymer include FZ-2203, -2207, -2222 and -2166 (products of Nippon Unicar Co., Ltd.).
[0153] Examples of the antifungal agent to be used in the invention include sodium dehydroacetate, sodium benzoate, sodium pyridinedithione-1-oxide, ethyl p-hydroxybenzoate, 1,2-benzisothiazolin-3-one and the salts thereof. These are used in an amount of preferably from 0.02 to 5.00% by weight.
[0154] Additionally, details thereof are described in Bokin Bobaizai Jiten (compiled by Nihon Bokin BObai Gakkai Jiten Henshu Iinkai), etc.
[0155] Examples of the rust inhibitor include acid sulfites, sodium thiosulfate, ammonium thioglycolate, diisopropylammonium nitrite, pentaerythritol tetranitrate, dicyclohexylammonium nitrite and benzotriazole. These are used in a content of preferably from 0.02 to 5.00% by weight in the ink.
[0156] The pH-adjusting agent to be used in the invention can preferably be used for adjusting pH or for imparting dispersion stability, and the pH of the ink at 23° C. is adjusted to 8 to 11, preferably to 7 to 9. In the case where the pH is less than 8, solubility of the dye is so reduced that the nozzle is liable to be clogged whereas, in the case where the pH exceeds 11, water resistance tends to be deteriorated. As the pH-adjusting agent, there are illustrated basic materials such as organic bases and inorganic alkalis and acidic materials such as organic acids and inorganic acids.
[0157] Examples of the organic base include triethanolamine, diethanolamine, N-methyldiethanolamine and dimethylethanolamine. Examples of the inorganic alkali include hydroxides of an alkali metal (e.g., sodium hydroxide, lithium hydroxide and potassium hydroxide), carbonates (e.g., sodium carbonate and sodium hydrogen carbonate), and ammonium. Examples of the organic acid include acetic acid, propionic acid, trifluoroacetic acid and alkylsulfonic acid. Examples of the inorganic acid include hydrochloric acid, sulfuric acid and phosphoric acid. As the pH-adjusting agent, triethanolamine is particularly preferably used.
[0158] The surface tension-adjusting agent to be used in the invention includes nonionic, cationic and anionic surfactants. Examples of the anionic surfactant include fatty acid salts, alkylsulfates, alkylbenzenesulfonates, alkylnaphthalenesulfonates, dialkylsulfosuccinates, alkylphosphates, naphthalenesulfonic acid-formalin condensate and polyoxyethylene alkylsulfates, examples of the nonionic surfractants include polyoxyethylene alkyl ether, polyoxyethylene alkylaryl ether, polyoxyethylene fatty acid ester, sorbitan fatty acid ester, polyoxyethylenesorbitan fatty acid ester, polyoxyethylene alkylamine, glycerin fatty acid ester, and oxyethylene-oxypropylene block copolymer.
[0159] In the invention, acetylene glycol-based surfactants (preferably acetylenic polyoxyethylene oxide) are preferably used, and examples thereof include SURFYNOLS (SURFYNOL 465, etc.; manufactured by Air Products & Chemicals Co.). The content of the surfactant based on the whole weight of the ink composition is from 0.001 to 15% by weight, preferably from 0.005 to 10% by weight, more preferably from 0.01 to 5% by weight, particularly preferably from 0.1 to 5% by weight.
[0160] The surface tension of the ink to be used in the invention at 25° C. is preferably from 20 to 50 mN/m or less, more preferably from 20 to 40 mN/m or less, with respect to both dynamic surface tension and static surface tension. In case where the surface tension exceeds 50 mN/m, there results seriously deteriorated ejection stability and printing quality such as blurring upon color mixing and misting. On the other hand, in case where the surface tension of the ink is less than 20 mN/m, there can result printing failure due to deposition of the ink to the surface of a printing stock upon ejection.
[0161] The viscosity of the ink of the invention at 25° C. is preferably from 1 to 30 mPa·s, more preferably from 2 to 15 mpa·s, particularly preferably from 2 to 10 mpa·s. In case where it exceeds 30 mPa·s, there result a slow fixing rate of a recorded image and deterioration of ejection performance. On the other hand, in case where it is less than 1 mpa·s, there results blurring of recorded image, leading to deterioration of quality.
[0162] Adjustment of the viscosity can freely be conducted by controlling the addition amount of the ink solvent. Examples of the ink solvent include glycerin, diethylene glycol, triethanolamine, 2-pyrrolidone, diethylene glycol monobutyl ether and triethylene glycol monobutyl ether. Also, a viscosity-adjusting agent may be used. Examples of the viscosity-adjusting agent include water-soluble polymers such as celluloses and polyvinyl alcohol and nonionic surfactants. More detailed descriptions are given in Nendo Chosei Gijutsu (published by Gijutsu Joho Kyokai in 1999), chapter 9 and Inku Jetto Purinta Yo Kemikaruzu (enlarged in 1998)— Zairyo No Kaihatsu Doko.Tenbo Chosa —(published by CMC in 1997), pp. 162-174.
[0163] The ink to be used in the invention is preferably used for forming a full-color image as well as a mono-color image. In order to form a full-color image, a magenta ink, a cyan ink and a yellow ink can be used. Also, in order to adjust color tone, a black ink may further be used.
[0164] Further, in the recording method of the invention (preferably inkjet recording method), other yellow dyes can be used together with the dye of the invention represented by formula (1) within a range wherein the effects of the invention are obtained. Yellow dyes to be used include aryl or heteryl azo dyes having, as a coupling component (hereinafter referred to as “coupler component”), a phenol, an aniline or a hetero ring such as pyrazolone or pyridine or an open-chain type active methylene compound; azomethine dyes having, for example, an open-chain type active methylene compound as a coupler component; methane dyes such as a benzylidene dye and a monomethine oxonol dye; and quinone-based dyes such as a naphthoquinone dye and an anthraquinone dye. Other dyes than these can be selected from among quinophthalone dyes, nitro-nitroso dyes, acridine dyes and acridinone dyes.
[0165] Examples of the magenta dye which can be used within a range wherein the effects of the recording method of the invention can be obtained include aryl or heteryl azo dyes having, for example, a phenol, a naphthol or an aniline as a coupler component; azomethine dyes having, for example, a pyrazolone or a pyrazolotriazole as a coupler component; methane dyes such as an arylidene dye, a styryl dye, a merocyanine dye, a cyanine dye and an oxonol dye; carbonium dyes such as a diphenylmethane dye, a triphenylmethane dye and a xanthene dye; quinone dyes such as naphthoquinone, anthraquinone and anthrapyridone; and condensed polycyclic dyes such as dioxazine dyes.
[0166] Examples of the cyan dye which can be used within a range wherein the effects of the recording method of the invention can be obtained include aryl or heteryl azo dyes having, for example, a phenol, a naphthol or an aniline as a coupler component; azomethine dyes having, for example, a phenol, a naphthol or a pyrrolotriazole as a coupler component; polymethine dyes such as a cyanine dye, an oxonol dye and a merocyanine dye; carbonium dyes such as a diphenylmethane dye, a triphenylmethane dye and a xanthene dye; phthalocyanine dyes; anthraquinone dyes and indigo•thioindigo dyes.
[0167] Examples of the applicable black color material include disazo, trisazo and tetrazodyes and, in addition, a dispersion of carbon black.
[0000] (Ink Recording Method)
[0168] The ink of the invention is recorded on a material to be recorded. In the inkjet recording method which is preferred in the invention, energy is imparted to the aforesaid ink for use in inkjet recording to form an image on a known image-receiving material used as a material on which an image is to be recorded, i.e., plain paper, resin-coated paper, paper for exclusive use for inkjet recording described in, for example, JP-A-8-169172, JP-A-8-27693, JP-A-2-276670, JP-A-7-276789, JP-A-9-323475, JP-A-62-238783, JP-A-10-153989, JP-A-10-217473, JP-A-10-235995, JP-A-10-337947, JP-A-10-217597 and JP-A-10-337947, film, paper commonly used with electrophotography, cloth, glass, metal or ceramic. Additionally, as an inkjet recording method of the invention, the description in JP-A-2003-306623, paragraph numbers 0093 to 0105 can be applied.
[0169] Upon formation of an image, a polymer latex compound may also be used for the purpose of imparting luster or water resistance or improving weatherability. As to the stage of imparting the latex compound to an image-receiving material, the latex compound may be imparted before, after or simultaneously with imparting the colorant. Therefore, as to where to add the latex compound, it may be added to an image-receiving paper or an ink or may be used independently as a liquid substance.
[0170] Specifically, methods described in JP-A-2002-166638, JP-A-2002-121440, JP-A-2002-154201, JP-A-2002-144696, JP-A-2002-080759, JP-A-2002-187342 and JP-A-2002-172774 can preferably be employed.
[0171] Recording paper and recording film to be used for inkjet printing using the ink of the invention are described below. As a support in the recording paper and the recording film, those which comprise chemical pulp such as LBKP or NBKP, mechanical pulp such as GP, PGW, RMP, TMP, CTMP, CMP or CGP or waste paper pulp such as DIP and are manufactured by mixing, as needed, conventionally known additives such as a pigment, binder, sizing agent, fixing agent, cationic agent and paper strength-increasing agent and using various machines such as a Fourdrinier machine or a wire cylinder paper machine can be used. In addition to these supports, any of synthetic paper and plastic film sheet may be used. The thickness of the support is desirably from 10 to 250 μm and the basis weight is desirably from 10 to 250 g/m2. An ink-receptive layer and a back coat layer may be provided directly on the support, or may be provided after size-pressing with starch or polyvinyl alcohol or after providing on the support an anchor coat layer. Further, the support may be subjected to surface-smoothening treatment by means of a calendering apparatus such as a machine calender, TG calender or soft calender. In the invention, paper laminated on both sides with a polyolefin (e.g., polyethyolene, polystyrene, polyethylene terephthalate, polybutene or the copolymer thereof) or plastic film is more preferably used as the support. It is preferred to add a white pigment (e.g., titanium oxide or zinc oxide) or a toning dye (e.g., cobalt blue, ultramarine or neodymium oxide) to the polyolefin.
[0172] The ink-receptive layer to be provided on the support contains a pigment or a aqueous binder. As the pigment, a white pigment is preferred, and examples thereof include white inorganic pigments such as calcium carbonate, kaolin, talc, clay, diatomaceous earth, synthetic amorphous silica, aluminum silicate, magnesium silicate, calcium silicate, aluminum hydroxide, alumina, lithopone, zeolite, barium sulfate, calcium sulfate, titanium dioxide, zinc sulfide and zinc carbonate; and organic pigments such as styrene-based pigment, acrylic pigment, urea resin and melamine resin. As the white pigment to be incorporated in the ink-receptive layer, porous inorganic pigments are preferred, with synthetic amorphous silica having a large pore area being particularly preferred. The synthetic amorphous silica may be either of silicic acid anhydride obtained by a dry production method and silicic acid hydrate obtained by a wet production method, with the use of silicic acid hydrate being particularly preferred.
[0173] The inkjet recording method of the invention is not limited as to the type of inkjet recording, and may be employed for known recording types such as a charge-controlling type of ejecting an ink utilizing static attraction force; a drop-on-demand type (pressure pulse type) of using an inkjet head capable of forming an ink droplet through mechanical deformation of an electrorestrictive strain element and utilizing vibration pressure of a piezoelectric element; a sound inkjet type wherein an electric signal is converted to a sound beam, and the sound beam is directed to an ink to eject an ink utilizing the radiation pressure; and a thermal inkjet type of heating an ink to form a bubble and utilizing the generated pressure. The inkjet recording method includes a method of ejecting many small-volume ink droplets with a low concentration, called photoink; a method of using a plurality of inks having substantially the same hue and different concentration to improve image quality; and a method of using a colorless, transparent ink.
EXAMPLES
[0174] The invention will be described in more detail by reference to the following examples, but the invention should not be construed as being limited thereto.
Example 1
[0175] Ultrapure water (resistance value: 18 MΩ or more) was added to the following components to make the total 1 liter, followed by stirring for 1 hour under heating at 30 to 40° C. Then, the mixture was filtered through a microfilter of 0.25 μm in average pore size under reduced pressure to prepare a yellow ink solution Y-101.
(Formulation of yellow ink Y-101) Yellow dye (Dye 1) 50 g/l Urea 10 g/l Triethylene glycol 90 g/l Glyderin 90 g/l Triethylene glycol monobutyl ether 90 g/l 2-Pyrrolidone 20 g/l Triethanolamine 7 g/l Surfinol 465 (manufactured by Nissin Kagaku) 10 g/l Proxel XL2 (manufactured by Avecia) 5 g/l
[0176] Further, a light magenta ink, a magenta ink, a light cyan ink, a cyan ink and a black ink were prepared by changing the kind of dye and the additives. Thus, an ink set 101 containing them in contents given in Table 1 was prepared.
TABLE 1 (Formulation of ink set 101) Light Light magenta Magenta cyan Cyan Yellow Black Dye (g/l) M-2 M-2 C-1 C-2 Dye-40 Bk-1 (60) (8.7) (32) (17) (50) (50) Bk-2 (15) Dye-40 (10) Urea (g/l) 20 20 20 20 10 50 Triethylene 100 20 50 100 90 20 glycol (g/l) Glyderin 120 100 120 110 90 100 (g/l) Triethylene 110 100 100 90 90 80 glycol monobutyl ether (g/l) 2- 30 10 20 35 20 30 Pyrrolidone (g/l) 1,2- 30 10 — 35 — 30 Hexanediol (g/l) Triethanol- 7 5 2 5 7 4 amine (g/l) Surfinol 10 10 10 11 10 10 465 (g/l) Proxel (g/l) 5 5 3 3 5 3
[0177] Next, ink sets 102 to 108 were prepared by changing the yellow ink used in ink set 101 to the following yellow inks Y-102 to Y-108.
Y-101: Yellow dye (Dye-40; 50 g/l), Compound of the invention was not added. Y-102: Yellow dye (Dye-1; 50 g/l), Compound of the invention was not added. Y-103: Yellow dye (Dye-40; 50 g/l), Compound of the invention (2-naphthoic acid; 30 g/l) Y-104: Yellow dye (Dye-40; 50 g/l), Compound of the invention (malonic acid; 20 g/l) Y-105: Yellow dye (Dye-40; 50 g/l),
[0183] Compound of the invention (p-toluenesulfonic acid; 25 g/l)
Y-106: Yellow dye (Dye-1; 50 g/l),
[0185] Compound of the invention (pyridine-2-carboxylic acid; 20 g/l)
Y-107: Yellow dye (Dye-40; 50 g/l),
[0187] Compound of the invention (pyridine-2-carboxylic acid; 20 g/1)
Y-108: Yellow dye (Dye-62; 50 g/l),
[0189] Compound of the invention (pyridine-2-carboxylic acid; 20 g/l)
[0190] The oxidation potential of the yellow dye (Dye 1, Dye 40, Dye 62) used is a value obtained by using a 1 mmol/l aqueous solution of the dye and employing the aforesaid measuring method. Oxidation potential: Dye 1 (1.33), Dye 40 (1.32), Dye 62 (1.31); spectral absorption maximum (in water): Dye 1 (452 nm), Dye 40 (457 nm), Dye 62 (436 nm).
[0191] Additionally, the variation of pH by the addition of the compound of the invention was adjusted to be within a range of from 8 to 8.5 with a base (e.g., KOH) or an acid (e.g., citric acid).
[0192] Also, as a comparison type, a yellow ink cartridge of PM-G800 manufactured by EPSON K.K. was used as an ink set 109.
[0193] Each of these ink sets was mounted in a cartridge of an inkjet printer PM-G800 manufactured by EPSON, and a photographic paper “Kotaku” manufactured by EPSON and a lustrous paper manufactured by EPSON were used as image-receiving sheets. A yellow mono-color pattern wherein image density is stepwise changed and a green, red or gray image pattern were recorded on each paper using PM-G800. Image quality, ink-ejecting performance and image fastness were evaluated.
[0000] (Evaluation Test)
[0000]
1) Stability of ejecting an ink was evaluated by setting the cartridge in the printer and, after confirming ejection of the ink through all nozzles, printing 20 sheets of A4-size paper, followed by evaluating according to the following standard.
A: No disorder of printed image from the start to the end of printing B: Output with some disorder in printed image generated. C: Disorder of printed image was observed from the start to the end of printing.
[0198] This experiment was conducted immediately after filling the ink (ejection performance A) and after storing the ink cartridge for 2 weeks under the condition of 40° C. and 80% RH (ejection performance B).
2) As to image preservability of the yellow dye, evaluation was conducted in the following manner by measuring the yellow density of gray image formed by using a gray image pattern. (1) Light fastness was evaluated by measuring image density Ci using X-rite 310 immediately after printing and, after irradiating the image with a xenon light (100,000 lx) using a weather meter made by Atlas for 10 days, again measuring the image density Cf, and determining the dye-remaining ratio, (Cf/Ci)×100. The dye-remaining ratio was evaluated at three points of 0.7, 1.4 and 1.8 in reflection density. A sample which gave the dye-remaining ratio of 85% or more at all of the three points was ranked A, a sample which gave the dye-remaining ratio of less than 85% at one point was ranked B, a sample which gave the dye-remaining ratio of less than 85% at two points was ranked C, and a sample which gave the dye-remaining ratio of less than 85% at all points was ranked D. (2) Heat fastness was evaluated by measuring image density before and after storing a sample for 7 days under the condition of 80° C. and 60% RH using X-rite 310 to determine the dye-remaining ratio. The dye-remaining ratio was evaluated at three points of 0.7, 1.4 and 1.8 in reflection density. A sample which gave the dye-remaining ratio of 85% or more at all of the three points was ranked A, a sample which gave the dye-remaining ratio of less than 85% at one point was ranked B, a sample which gave the dye-remaining ratio of less than 85% at two points was ranked C, and a sample which gave the dye-remaining ratio of less than 85% at all points was ranked D. (3) Resistance to ozone was evaluated by leaving a sample for 10 days in a box wherein the ozone gas concentration was set at 5 ppm, measuring the image density before and after leaving the sample under the ozone gas using a reflection densitometer (X-rite 310TR), and evaluating the resistance to ozone in terms of the dye-remaining ratio. Additionally, the reflection density was measured at three points of 0.7, 1.4 and 1.8. The ozone gas concentration within the box was established by means of an ozone gas monitor (Model: OZG-EM-01) manufactured by APPLICS.
[0203] Evaluation was conducted in four ranks. That is, a sample which gave the dye-remaining ratio of 85% or more at all of the three points was ranked A, a sample which gave the dye-remaining ratio of less than 85% at one point was ranked B, a sample which gave the dye-remaining ratio of less than 85% at two points was ranked C, and a sample which gave the dye-remaining ratio of less than 85% at all points was ranked D.
3) Generation of metallic luster was visually evaluated according to the following standard by observing the solid printed area of yellow or red color.
A: Metallic luster was not observed. B: Metallic luster was observed somewhat. C: Metallic luster was clearly observed.
[0208] The results thus obtained are shown in the following table.
TABLE 2 Ejection Ejection Metallic luster Metallic luster Ink set performance A performance B (1) Light (2) Heat (3) Ozone Photographic paper Lustrous paper Note 101 A A A A A A C For comparison 102 A A A A B B C For comparison 103 A A A A A A A Invention 104 A A A A A A A Invention 105 A A A A A A A Invention 106 A A A A A A A Invention 107 A A A A A A A Invention 108 A A A A A A A Invention 109 A A B B D A A For comparison
[0209] It is seen from the results shown in the table that, in the system using the ink of the invention, excellent ejection performance and excellent weatherability can be obtained, with depressing generation of metallic luster.
Two of R's:SO 2 CH 2 CH 2 CH 2 SO 3 Li
[0211] The other two of R's:
[0212] Two of R's:SO 2 CH 2 CH 2 CH 2 SO 3 K
[0213] The other two of R's:SO 2 CH 2 CH 2 CH 2 SO 2 NH(CH 2 ) 2 O(CH 2 ) 2 OH
[0214] While the invention has been described in detail and with reference to specific embodiments thereof, it will be apparent to one skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope thereof.
[0215] 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 herein. | A novel ink composition, which has an absorption characteristic excellent in color reproducibility as a yellow color of one of the three primary colors, which has enough fastness against light, heat and humidity, and which does not cause bronze phenomenon, is provided. The ink composition contains water, a yellow dye having an oxidation potential nobler than 1.0 V, and an aromatic compound, aliphatic compound and/or a salt thereof having at least one of carboxyl group, sulfo group and phosphoric acid group. | 2 |
This application is a continuation-in-part of and claims priority to Ser. No. 10/777,366, filed Feb. 12, 2004 now abandoned, which is fully incorporated herein by reference.
FIELD OF THE INVENTION
The subject invention relates generally to build apparatus and method for applying electronics to a tire for the purpose of monitoring tire condition parameters and, more specifically, to a tire build apparatus and method for incorporating an annular antenna and associated electronics into a tire.
BACKGROUND OF THE INVENTION
It is common to employ annular apparatus, including an antenna, for electronically transmitting tire or wheel identification or other data at radio frequency. The apparatus includes a radio-frequency tag, or transponder, comprising an integrated circuit chip having data capacity at least sufficient to retain identification information for the tire or wheel. Other data, such as the inflation pressure of the tire or the temperature of the tire or wheel at the transponder location, can be transmitted by the transponder along with the identification data.
The annular antenna is tire-mounted and transmits, at radio frequencies, data from the transponder to a reader mounted on the wheel assembly. The antenna and transponder may be incorporated into a tire during “pre-cure” manufacture of the tire. The integrity of the connection between the tire and antenna is greatly enhanced by a pre-cure assembly procedure. In practice, however, it is very difficult to do this. Both radial ply and bias ply tires undergo a substantial diametric enlargement during the course of manufacture. Bias ply tires are expanded diametrically when inserted into a curing press, which typically has a bladder that forces the green tire into the toroidal shape of the mold enclosing it. Radial ply tires undergo diametric expansion during the tire building or shaping process and a further diametric expansion during the course of curing. An annular antenna and the electronic tag associated therewith built into the tire in a pre-cure process, therefore, must endure significant stresses that can result in component failure. The electronic tag and the connection between the tag and the antenna, in particular, is vulnerable to damage from the forces imposed from pre-cure assembly to tire.
To avoid damaging the electronic tag or the connection between the tag and the annular antenna during the curing procedure, an alternative known approach is to assemble the tag and antenna into a separate annular apparatus for post-cure attachment to the tire. The annular apparatus may be attached to the tire after the tire is cured by adhesive or other known techniques. While such an approach avoids damaging the tag electronics during tire manufacture, adhesive attachment of the antenna and tag to a tire in a post-cure procedure has certain drawbacks. First, the procedure adds labor, and hence cost, to the manufacturing process. Secondly, the security of the attachment between the annular apparatus and the tire is dependent upon the efficacy of the adhesive system employed. Development of a suitable adhesive that is inexpensive, convenient to use, and durable enough to function throughout the life cycle of a tire has proven problematic.
Accordingly, a need remains for a system and method of applying tag electronics to a tire that is convenient, cost effective, and reliable. Such a procedure should further ensure the functional safety of the electronics and result in a positive electrical connection between the antenna and tag electronics. Finally, such a procedure ideally would incorporate the advantages, but avoid the shortcomings, of both the pre-cure and post-cure assembly alternatives discussed above.
SUMMARY OF THE INVENTION
Pursuant to one aspect of the invention a method for pre-cure application of an annular antenna assembly to a tire comprises the steps: forming within a rigid core defining an interior surface of the tire a core recess complementarily configured to the annular antenna assembly; positioning the annular antenna assembly within the core recess; building an uncured carcass of the tire around the rigid core entrapping the annular antenna assembly within the core recess; cross-bonding the annular antenna assembly to the inner surface of the tire during a cure cycle; and removing the cured tire and annular assembly from the rigid core.
According to another aspect of the invention, the annular antenna assembly may alternatively be assembled on the rigid core from components or pre-assembled off-site and transferred as a unitary assembly to the rigid core. In connection with the invention a tire mold is provided including a rigid core for the practice of the inventive method. A tire manufactured pursuant to the inventive method constitutes yet a further aspect of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be described by way of example and with reference to the accompanying drawings in which:
FIG. 1 is a perspective view of a tire having an annular antenna assembly incorporated therein, a portion of the tire being removed for the purpose of illustration.
FIG. 2 is a fragmentary top plan view of a section of the annular antenna ring and transponder component.
FIG. 3 is a partial transverse section view of a representative tire surrounding a rigid mold core and annular antenna assembly.
FIG. 4 is a schematic partial radial cross section of a mold having an annular antenna assembly incorporated therein pursuant to the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring initially to FIGS. 1 and 2 , an annular antenna assembly 10 is shown deployed within a tire 12 . The tire 12 is formed from conventional materials such as rubber or rubber composites by conventional means and may comprise a radial ply or bias ply configuration. A typical tire 12 is configured having a tread 14 , a shoulder 16 , an annular sidewall 18 , and a terminal bead 20 . An inner liner 22 is formed and defines a tire cavity 24 . The tire 12 is intended for mounted location upon an annular rim 26 having a peripheral rim flange 28 and an outer rim flange surface 30 . Rim 26 is conventionally configured and composed of a suitably strong metal such as steel.
An annular antenna 32 is provided and, in the preferred embodiment, embodies a sinusoidal configuration. Antenna 32 may be alternatively configured into alternative patterns or comprise a straight wire(s) if desired and may be filament wire, or cord or stranded wire. Acceptable materials for the wire include steel, aluminum, copper or other electrically conducting wire. As mentioned previously, the wire diameter is not generally considered critical for operation as an antenna and multiple strands of fine wire is preferred. The curvilinear form of antenna 32 provides flexibility and minimizes the risk of breakage during manufacture and use of the tire.
With continued reference to FIGS. 1 and 2 , a tag carrier 34 of the general type described above is provided and may include means for sensing tire parameters such as pressure and temperature. Included as part of the apparatus 10 is a carrier strip of material 36 formed into the annular configuration shown. Carrier strip 36 is formed of electrically insulating, preferably semi-rigid elastomeric material common to industry such as rubber or plastic. The strip 36 is formed to substantially encapsulate the antenna wire(s) 32 and at least a portion of the tag carrier 34 . In the post manufacturing state shown in FIG. 1 , therefore, the apparatus 10 comprises antenna 32 , tag carrier 34 , and carrier strip 36 , in a unitary, generally circular, assembly. The diameter of the apparatus assembly 10 is a function of the size of the tire 12 . The preferred location of the antenna assembly 10 on the tire is on the tire just above the rim flange 30 . Such a location minimizes stress forces on the assembly from operation of the tire and minimizes interference to RF communication between the tag and an external reader (not shown) that might otherwise be caused by the metal rim. Other mounting locations of the antenna assembly 10 on the tire, however, may be employed if desired for specific tire applications.
In FIG. 3 , the tire 12 is shown in greater detail. The subject invention may be utilized in tires of various construction and size. For example, the tire 12 may be a commonly available radial passenger or light truck tire. By way of example, without any intent to limit the invention thereto, one such tire is taught by U.S. Pat. No. 6,358,346, incorporated herein by reference. The tire 12 includes a carcass 40 having a tread region 14 , a shoulder region 16 , and a sidewall region 18 extending from the shoulder 16 to an annular bead 20 . A ply structure 42 is generally provided within sidewall 18 and one or more belt plies 44 , 46 are located at the tread region 14 . The inner liner 22 represents the interior surface of the tire and extends continuously from the bead, along the sidewall region, and across the tread region.
It is known to manufacture a tire using a rigid core build process. Such a process is shown and described in U.S. Pat. No. 4,985,692, incorporated herein by reference. With reference to FIGS. 3 and 4 , in a solid core build process the tire is built upon a rigid core 48 . By “rigid”, it should be understood as “substantially non-deformable” in contrast with elastic and deformable tire building techniques. A material suitable in the formation of the rigid core 48 is steel but other suitably rigid materials may be used as desired. Additionally, while common rigid core build techniques, such as those set forth in U.S. Pat. No. 4,895,692 utilize a plurality of sliding segments in order to close the mold, the invention is not limited thereto. The invention may be used in other types of rigid cores that close in differing ways or comprise a unitary, non-segmented structure if desired.
A segmented rigid core mold 50 is shown in FIG. 4 by way of example, it being understood that the invention need not be limited to the mold configuration shown. The mold 50 includes segments 52 that come into concordance with the side parts 54 via contact surfaces 56 , 57 . Each segment also has transverse contact surfaces (not shown) which in closed position adjoin the transverse faces of the adjacent segments. The radially inner faces 58 of the core 48 come, in closed position, into contact with the corresponding faces 60 arranged in the extension 62 of each side part 54 beyond a zone 64 assuring the molding of the radially inner surface of the beads of the tire. A cavity 65 is defined between the core 48 and mold segments 52 , 54 defined along inward toroidal surfaces to create the structure of the tire to be molded.
Pursuant to the invention, it is intended that the antenna assembly 10 be incorporated and bonded to a tire 12 during the cure cycle. In order to facilitate this objective, an annular groove or recess 66 is formed within an outward surface of the mold core 48 . The rigid composition of the core 48 facilitates the creation of an annular recess therein by machining or other known manufacturing techniques. The recess 66 is configured and dimensioned to receive antenna assembly 10 therein as shown in FIGS. 3 , 4 . The location of recess 66 within core 48 is generally preferred to be a distance nominally one inch above the tire bead, as indicated in FIG. 3 . However, other locations may be used at the user's preference.
The recess 66 is provided with an enlarged socket 68 formed therein configured complementary with the transponder component 34 of the assembly. Any other geometric irregularity that is present within the assembly may be accommodated by the inclusion of a complementary recess or socket within the recess 66 . The recess 66 preferably extends in a circular path about the core 48 , however, a non-circular or irregular path may also be employed. The annular recess is sized in a depth dimension to allow the annular assembly 10 to project from the recess 66 a distance beyond the outer surface of core 48 for a purpose explained below. Insertion of the annular assembly 10 within recess 66 core 48 is preferably effected as a step preliminary to the building of the tire carcass 40 upon the core. Insertion of the annular assembly 10 into recess 66 may be accomplished manually or through the use of robotics or other known assembly methods.
Once the annular apparatus 10 is inserted into the recess 66 of core 48 , the tire carcass may be built upon the core beginning with the inner liner 22 in conventional fashion. The carcass this entraps and surrounds the annular apparatus within recess 66 . It will be appreciated that the annular apparatus 10 may be assembled on the core 48 from components, that is the transponder 34 , antenna wire(s) 32 , and the cover 36 . Alternatively, the assembly 10 may be assembled off-site and mounted to the core 48 as a unitary assembly. At the conclusion of the tire build procedure upon core 48 , the tire is subjected to a curing cycle in conventional fashion.
As a result of the vulcanization of tire 12 , the cover 36 of the assembly 10 is cross-bonded to the inner liner 22 and a strong mechanical connection is established therebetween. Protrusion of the assembly 10 from the recess 66 of core 48 enhances the cross-bonded connection between the cover 36 and the inner liner 22 and ensures that the connection is not compromised by the presence of air between the surfaces of cover 36 and inner liner 22 . Upon completion of the cure cycle, the tire 12 is removed from the mold 50 and from core 48 and includes an accurately positioned annular assembly 10 encircling the inner liner 22 . The transponder 34 is oriented within the recess 66 so that any sensor devices may be directed inward in the finished tire. For example, a pressure sensor may be directed toward and protrude into the cavity 24 of tire 12 if desired.
From the foregoing it will be appreciated that the subject invention satisfies the needs of the industry for a convenient, cost-effective, and reliable method for affixing an annular antenna assembly to an inner surface of the tire. The location of the annular assembly is easily selected by the user and precisely positions the assembly 10 relative to the tire 12 in a carefully controlled and repeatable manner. Moreover, no additional adhesive or hardware is required to effect the connection between the assembly 10 and tire 12 . Since the groove is configured to complement the annular assembly 10 , a positive seating of the assembly 10 within the groove 66 is possible. Additional protrusions may be incorporated within assembly cover 36 if desired by which to orient assembly 10 within groove 66 . The sides of the rigid core 48 defining groove 66 protect the annular assembly 10 during the vulcanization of the tire and damage to the assembly 10 from the forces within the tire during the cure cycle is avoided.
Variations in the present invention are possible in light of the description of it provided herein. While certain representative embodiments and details have been shown for the purpose of illustrating the subject invention, it will be apparent to those skilled in this art that various changes and modifications can be made therein without departing from the scope of the subject invention. It is, therefore, to be understood that changes can be made in the particular embodiments described which will be within the full intended scope of the invention as defined by the following appended claims. | Apparatus and a method for pre-cure application of an antenna assembly to a tire comprises the method steps: forming within a rigid core defining an interior surface of the tire a core recess complementarily configured to the antenna assembly; positioning the antenna assembly within the core recess; building an uncured carcass of the tire around the rigid core entrapping the antenna assembly within the core recess; cross-bonding the antenna assembly to the inner surface of the tire during a cure cycle; and removing the cured tire and assembly from the rigid core. | 1 |
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] The priority of Korean patent application number 10-2007-0122950, filed on Nov. 29, 2007, which is incorporated by reference in its entirety, is claimed.
BACKGROUND OF THE INVENTION
[0002] The present invention generally relates to a semiconductor device, and more specifically, to a semiconductor device having a device isolation structure and a method for fabricating the same.
[0003] Generally, manufacturers reduce device size to increase operating speed of the semiconductor device such as a transistor. In the case of transistors, if the device size becomes smaller, a breakdown voltage of a source/drain is reduced, junction capacitance is increased, and a short channel effect (SCE) is generated.
[0004] Efforts for improving an operating speed of the device has moved from reduction of the device size to improvement of carrier mobility of transistors and reduction of the SCE. The carrier mobility of the transistor is improved by straining the semiconductor device.
[0005] In order to improve an operating characteristic of NMOS and PMOS transistors, when stress is applied to the transistor, a tensile stress and a compressive stress are applied to the transistor along a channel direction of the device.
[0006] In order to improve the carrier mobility, different types of stress are applied to each transistor depending on the type of transistor. For example, a stress may be regulated depending on spacer materials and deposition conditions when a gate spacer is formed.
[0007] Stress can be regulated by adjusting a device isolation structure adjacent to the channel of the device. For example, in a device isolating process for defining an active region, an oxide film is formed on a sidewall of the device isolation structure, and a liner nitride film is formed over the device isolation structure. In some cases, the liner nitride film is removed from some PMOS transistors.
[0008] However, current increasing effects in transistors are hindered by the above method because a different stress is applied to the transistor in horizontal and longitudinal directions and the stress is differentiated depending on a distance of the adjacent active region.
BRIEF SUMMARY OF THE INVENTION
[0009] Various embodiments of the present invention are directed at providing a semiconductor device having an improved device isolation structure so that more current may flow through a channel in the same threshold voltage.
[0010] Various embodiments of the present invention are directed at preventing a decrease of driving currents due to stress.
[0011] According to an embodiment of the present invention, a semiconductor device includes a device insulation region having a liner nitride film formed on a part of sidewalls of a device isolation trench.
[0012] The part of the sidewalls may include the sidewalls in a first direction intersected by a longitudinal direction of a gate. The part of the sidewalls may include the sidewalls in a second direction parallel to a longitudinal direction of a gate. The part of the sidewalls may include one of both sidewalls of a first direction intersected by a longitudinal direction of a gate and one of both sidewalls of a second direction intersected by the first direction of the sidewalls surrounding an active region. The part of the sidewalls may exclude one of both sidewalls of a first direction intersected by a longitudinal direction of a gate or one of both sidewalls of a second direction intersected by the first direction of the sidewalls surrounding an active region. The part of sidewalls may include only one sidewall of the sidewalls surrounding an active region. The semiconductor device may be a PMOS transistor.
[0013] According to an embodiment of the present invention, a semiconductor device includes a device isolation region having a liner oxide nitride film formed on a part of sidewalls of a device isolation trench.
[0014] According to an embodiment of the present invention, a method for fabricating a semiconductor device includes forming a trench in a semiconductor substrate that defines an active region on the semiconductor substrate; forming a liner nitride film on a partial sidewall of the trench; forming a device isolation region over the trench including the liner nitride film; and forming a gate over the active region.
[0015] The forming-a-liner-nitride-film step includes: depositing the liner nitride film sidewalls of the trench; and selectively removing the liner nitride film deposited on the other part of the sidewalls of the trench. The liner nitride film is formed by thermal treatment under an atmosphere of NH 3 , N 2 O and NO. The removing-the-liner-nitride-film step includes: forming a mask for exposing the liner nitride film deposited on the other part of sidewalls which are intersected by a longitudinal direction of the gate; removing the exposed liner nitride film; and removing the mask. The removing-the-liner-nitride-film step includes: forming a mask for exposing the liner nitride film deposited on the other part of the sidewalls which are parallel to a longitudinal direction of the gate; removing the exposed liner nitride film; and removing the mask. The removing-the-liner-nitride-film step includes: forming a mask for exposing the liner nitride film deposited on the other part of the sidewalls which include one of the sidewalls in a longitudinal direction of the gate and one of the sidewalls in a second direction intersected by the first direction; removing the exposed liner nitride film; and removing the mask. The removing-the-liner-nitride-film step includes: forming a mask for exposing the liner nitride film deposited on the other part of sidewalls which include one of the sidewalls in a first direction intersected by a longitudinal direction of the gate or one of the sidewalls in a second direction intersected by the first direction; removing the exposed liner nitride film; and removing the mask. The liner nitride film is removed by dry etching. The liner nitride film is removed by wet etching with H 3 PO 4 . The device isolation region includes a spin-on-dielectric (SOD) oxide film.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] FIG. 1 is a diagram illustrating a semiconductor device according to an embodiment of the present invention.
[0017] FIGS. 2 a to 2 h are cross-sectional diagrams illustrating a method for fabricating a semiconductor device according to an embodiment of the present invention.
[0018] FIGS. 3 a to 3 c are cross-sectional diagrams illustrating a method for fabricating a semiconductor device according to an embodiment of the present invention.
[0019] FIG. 4 is a cross-sectional diagram illustrating a semiconductor device according to an embodiment of the present invention.
[0020] FIG. 5 is a cross-sectional diagram illustrating a semiconductor device according to an embodiment of the present invention.
DESCRIPTION OF EMBODIMENTS
[0021] The present invention relates to a method for fabricating a semiconductor device that includes forming a liner nitride film not entirely on sidewalls of a trench but selectively on a part of the sidewalls to improve a device operating characteristic of a PMOS region.
[0022] FIG. 1 is a diagram illustrating a semiconductor device according to an embodiment of the present invention.
[0023] Referring to FIG. 1 , the semiconductor device includes an active region 102 , a gate region 104 , a device isolation region 106 and a source/drain region 108 . The active region 102 is defined by the device isolation region 106 . The gate region 104 includes the active region 102 and the device isolation region 106 adjacent to the active region 102 . The source/drain region 108 is formed in the active region 102 located at both sides of the gate region 104 .
[0024] FIGS. 2 a to 2 h are cross-sectional diagrams illustrating a method for fabricating a semiconductor device according to an embodiment of the present invention. FIGS. 2 a (i) to 2 g (i) are cross-sectional diagrams taken along I-I′ of FIG. 1 , and FIGS. 2 a (ii) to 2 g (ii) are cross-sectional diagrams taken along II-II′ of FIG. 1 .
[0025] Referring to FIG. 2 a , a pad oxide film 212 and a pad nitride film 214 are sequentially formed over a semiconductor substrate 210 .
[0026] Referring to FIG. 2 b , the pad nitride film 214 , the pad oxide film 212 and the semiconductor substrate 210 which correspond to the device isolation region 106 of FIG. 1 are etched to form a trench 216 .
[0027] Referring to FIGS. 2 c and 2 d , a sidewall insulating film 218 is formed on sidewalls of the trench 216 . The sidewall insulating film 218 may include a thermal oxide film.
[0028] A liner nitride film 220 is formed over the resulting structure of FIG. 2 c . The liner nitride film 220 is formed by thermal treatment under an atmosphere of NH 3 , N 2 O and NO. The liner nitride film 220 may be replaced with a liner oxide nitride film.
[0029] Referring to FIGS. 2 e and 2 f , a photoresist film (not shown) is formed over the liner nitride film 220 . The photoresist film is partially exposed and developed to form a mask pattern 222 that exposes a part of the liner nitride film 220 . The mask pattern 222 exposes the liner nitride film 220 formed on the sidewalls of the trench in a first direction. That is, the mask pattern 222 exposes the liner nitride film 220 formed on the sidewalls in a direction (i.e., horizontal direction in FIG. 1 ) intersected by a longitudinal direction of the gate region 104 of the active region 102 .
[0030] The liner nitride film 220 is removed by a dry etching method, a wet etching method or combinations thereof. The wet etching method is performed with H 3 PO 4 . The mask pattern 222 is then removed.
[0031] Referring to FIGS. 2 g and 2 h , a device isolation insulating film (not shown) is formed over the resulting structure of FIG. 2 f to fill the trench 216 . The device isolation insulating film includes a spin-on-dielectric (SOD) oxide film, a spin-on-glass (SOG) oxide film, a high density plasma (HDP) oxide film or combinations thereof. The device isolation insulating film includes a SOD oxide film in one embodiment of the present invention.
[0032] The device isolation insulating film is planarized until the semiconductor substrate 210 is exposed to form a device isolation region 230 . A gate 240 is then formed over the semiconductor substrate 210 .
[0033] A liner nitride film is not formed on the sidewalls of the trench in the first direction. That is, a liner nitride film is formed only on sidewalls located on opposite sides of the gate region 104 .
[0034] The device isolation structure according to the embodiment of the present invention is formed in a PMOS region.
[0035] In accordance with embodiments of the invention, although the sidewall in the first direction is formed with a straight line in FIG. 1 , it is not limited herein.
[0036] FIGS. 3 a to 3 c are cross-sectional diagrams illustrating a method for fabricating a semiconductor device according to an embodiment of the present invention. FIGS. 3 a (i) to 3 g (i) are cross-sectional diagrams taken along I-I′ of FIG. 1 , and FIGS. 3 a (ii) to 3 g (ii) are cross-sectional diagrams taken along II-II′ of FIG. 1 .
[0037] Referring to FIG. 3 a , a photoresist film (not shown) is formed over the resulting structure formed by the processes of FIGS. 2 a to 2 d.
[0038] The photoresist film is partially exposed and developed to form a mask pattern 322 that exposes a part of the liner nitride film 320 . The mask pattern 322 exposes the liner nitride film 320 formed on one of the trench sidewalls in a first direction.
[0039] Referring to FIG. 3 b , the exposed liner nitride film 320 is removed by a dry etching method, a wet etching method or combinations thereof. The wet etching method is performed with H 3 PO 4 . The mask pattern 322 is then removed.
[0040] Referring to FIG. 3 c , a device isolation insulating film (not shown) is formed over the resulting structure of FIG. 3 b to fill the trench. The device isolation insulating film includes a spin-on-dielectric (SOD) oxide film, a spin-on-glass (SOG) oxide film, a high density plasma (HDP) oxide film or combinations thereof. The device isolation insulating film includes a SOD oxide film in one embodiment of the present invention. The device isolation insulating film is planarized until the semiconductor substrate 310 is exposed to form a device isolation region 330 .
[0041] FIG. 4 is a cross-sectional diagram illustrating a semiconductor device according to an embodiment of the present invention. FIG. 4( i ) is a cross-sectional diagram taken along I-I′ of FIG. 1 , and FIG. 4( ii ) is a cross-sectional diagram taken along II-II′ of FIG. 1 .
[0042] In comparison with FIG. 2 g , a liner nitride film 420 is not formed on trench sidewalls 416 (i.e., sidewalls located at both sides of the gate region 104 ) in a second direction intersected by the first direction. That is, in one embodiment of the present invention, a liner nitride film is formed only on the sidewalls 416 in the first direction.
[0043] The semiconductor device of FIG. 4 may be fabricated by the method of FIGS. 2 a to 2 h except that a mask pattern is formed to expose the liner nitride film 420 not in the first direction but in the second direction.
[0044] FIG. 5 is a cross-sectional diagram illustrating a semiconductor device according to an embodiment of the present invention. FIG. 5( i ) is a cross-sectional diagram taken along I-I′ of FIG. 1 , and FIG. 5( ii ) is a cross-sectional diagram taken along II-II′ of FIG. 1 .
[0045] In comparison with FIG. 3 c , a liner nitride film 420 is not formed on one of trench sidewalls 516 (i.e., sidewalls located at both sides of the gate region 104 ) in a second direction.
[0046] The liner nitride film is not formed on one of the trench sidewalls 516 in the first direction or the second direction. For example, a liner nitride film may be formed on one both sidewalls 516 in the first direction and on only one of the sidewalls 516 in the second direction.
[0047] The liner nitride film may be formed on only one of the trench sidewalls surrounding each active region 102 .
[0048] As described above, according to an embodiment of the present invention, a nitride film is formed selectively on trench sidewalls to improve carrier mobility and prevent current reduction due to stress, thereby improving characteristics of the device.
[0049] The above embodiments of the present invention are illustrative and not limitative. Various alternatives and equivalents are possible. The invention is not limited by the type of deposition, etching polishing, and patterning steps described herein. Nor is the invention limited to any specific type of semiconductor device. For example, the present invention may be implemented in a dynamic random access memory (DRAM) device or non-volatile memory device. Other additions, subtractions, or modifications are obvious in view of the present disclosure and are intended to fall within the scope of the appended claims. | A semiconductor device includes a device isolation region formed on a part of shallow trench isolation (STI) sidewalls to relieve stress applied to an active region, thereby improving current flowing toward a channel region. | 7 |
[0001] This invention was made with government support under Contract No.: F33657-03-C-2044. The government therefore has certain rights in this invention.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to a tip turbine engine, and more particularly to a fan-turbine rotor assembly which includes an inducer formed therein.
[0003] An aircraft gas turbine engine of the conventional turbofan type generally includes a forward bypass fan, a compressor, a combustor, and an aft turbine all located along a common longitudinal axis. A compressor and a turbine of the engine are interconnected by a shaft. The compressor is rotatably driven to compress air entering the combustor to a relatively high pressure. This pressurized air is then mixed with fuel in a combustor and ignited to form a high energy gas stream. The gas stream flows axially aft to rotatably drive the turbine which rotatably drives the compressor through the shaft. The gas stream is also responsible for rotating the bypass fan. In some instances, there are multiple shafts or spools. In such instances, there is a separate turbine connected to a separate corresponding compressor through each shaft. In most instances, the lowest pressure turbine will drive the bypass fan.
[0004] Although highly efficient, conventional turbofan engines operate in an axial flow relationship. The axial flow relationship results in a relatively complicated elongated engine structure of considerable longitudinal length relative to the engine diameter. This elongated shape may complicate or prevent packaging of the engine into particular applications.
[0005] A recent development in gas turbine engines is the tip turbine engine. Tip turbine engines locate an axial compressor forward of a bypass fan which includes hollow fan blades that receive airflow from the axial compressor therethrough such that the hollow fan blades operate as a centrifugal compressor. Compressed core airflow from the hollow fan blades is mixed with fuel in an annular combustor and ignited to form a high energy gas stream which drives the turbine integrated onto the tips of the hollow bypass fan blades for rotation therewith as generally disclosed in U.S. Patent Application Publication Nos.: 20030192303; 20030192304; and 20040025490.
[0006] The tip turbine engine provides a thrust to weight ratio equivalent to conventional turbofan engines of the same class within a package of significantly shorter length.
[0007] One significant rotational component of a tip turbine engine is the fan-turbine rotor assembly. The fan-turbine rotor assembly includes a multitude of components which rotate at relatively high speeds to generate bypass airflow while communicating a core airflow through each of the multitude of hollow fan blades. A large percentage of the expense associated with a tip turbine engine is the manufacture of the fan-turbine rotor assembly and the integration of the inducer with the fan hub.
[0008] Accordingly, it is desirable to provide an inducer arrangement for a fan-turbine rotor assembly, which is relatively inexpensive to manufacture yet provides a high degree of reliability.
SUMMARY OF THE INVENTION
[0009] The fan-turbine rotor assembly for a tip turbine engine according to the present invention includes a fan hub which has an outer periphery scalloped by a multitude of elongated openings which extend into a fan hub web. Each elongated opening defines an inducer section and a blade receipt section to retain a hollow fan blade section. The blade receipt section retains each of the hollow fan blade sections adjacent each inducer section. An inner fan blade mount is located adjacent an inducer exhaust section to communicate a core airflow communication path from within each inducer section into the core airflow passage within each fan blade section.
[0010] The inducer is cast directly into the fan hub which minimizes leakage between each fan blade section and each inducer section to provide increased engine efficiency. Manufacturing and assembly is also readily facilitated.
[0011] The present invention therefore provides an inducer arrangement for a fan-turbine rotor assembly which is relatively inexpensive to manufacture yet provides a high degree of reliability.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] The various features and advantages of this invention will become apparent to those skilled in the art from the following detailed description of the currently preferred embodiment. The drawings that accompany the detailed description can be briefly described as follows:
[0013] FIG. 1 is a partial sectional perspective view of a tip turbine engine;
[0014] FIG. 2 is a longitudinal sectional view of a tip turbine engine along an engine centerline;
[0015] FIG. 3 is an exploded view of a fan-turbine rotor assembly;
[0016] FIG. 4 is an assembled view of a fan-turbine rotor assembly;
[0017] FIG. 5A is an expanded radial sectional view of an inducer section;
[0018] FIG. 5B is a sequential sectional view of the fan hub illustrating the inducer sections therewith;
[0019] FIG. 6 is a schematic view of airflow through the last stage of an axial compressor and into the inducer;
[0020] FIG. 7A is an expanded phantom perspective view of a fan blade mounted to a hub of a fan-turbine rotor assembly;
[0021] FIG. 7B is an expanded partially sectioned perspective view of a fan blade mounted to a hub of a fan-turbine rotor assembly; and
[0022] FIG. 7C is an expanded partially sectioned perspective view of a diffuser section of a fan blade.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0023] FIG. 1 illustrates a general perspective partial sectional view of a tip turbine engine type gas turbine engine 10 . The engine 10 includes an outer nacelle 12 , a rotationally fixed static outer support structure 14 and a rotationally fixed static inner support structure 16 . A multitude of fan inlet guide vanes 18 are mounted between the static outer support structure 14 and the static inner support structure 16 . Each inlet guide vane preferably includes a variable trailing edge 18 A.
[0024] A nose cone 20 is preferably located along the engine centerline A to smoothly direct airflow into an axial compressor 22 adjacent thereto. The axial compressor 22 is mounted about the engine centerline A behind the nose cone 20 .
[0025] A fan-turbine rotor assembly 24 is mounted for rotation about the engine centerline A aft of the axial compressor 22 . The fan-turbine rotor assembly 24 includes a multitude of hollow fan blades 28 to provide internal, centrifugal compression of the compressed airflow from the axial compressor 22 for distribution to an annular combustor 30 located within the rotationally fixed static outer support structure 14 .
[0026] A turbine 32 includes a multitude of tip turbine blades 34 (two stages shown) which rotatably drive the hollow fan blades 28 relative a multitude of tip turbine stators 36 which extend radially inwardly from the static outer support structure 14 . The annular combustor 30 is axially forward of the turbine 32 and communicates with the turbine 32 .
[0027] Referring to FIG. 2 , the rotationally fixed static inner support structure 16 includes a splitter 40 , a static inner support housing 42 and an static outer support housing 44 located coaxial to said engine centerline A.
[0028] The axial compressor 22 includes the axial compressor rotor 46 from which a plurality of compressor blades 52 extend radially outwardly and a compressor case 50 fixedly mounted to the splitter 40 . A plurality of compressor vanes 54 extend radially inwardly from the compressor case 50 between stages of the compressor blades 52 . The compressor blades 52 and compressor vanes 54 are arranged circumferentially about the axial compressor rotor 46 in stages (three stages of compressor blades 52 and compressor vanes 54 are shown in this example). The axial compressor rotor 46 is mounted for rotation upon the static inner support housing 42 through a forward bearing assembly 68 and an aft bearing assembly 62 .
[0029] The fan-turbine rotor assembly 24 includes a fan hub 64 that supports a multitude of the hollow fan blades 28 . Each fan blade 28 includes an inducer section 66 , a hollow fan blade section 72 and a diffuser section 74 . The inducer section 66 receives airflow from the axial compressor 22 generally parallel to the engine centerline A and turns the airflow from an axial airflow direction toward a radial airflow direction. The airflow is radially communicated through a core airflow passage 80 within the fan blade section 72 where the airflow is centrifugally compressed. From the core airflow passage 80 , the airflow is turned and diffused toward an axial airflow direction toward the annular combustor 30 . Preferably the airflow is diffused axially forward in the engine 10 , however, the airflow may alternatively be communicated in another direction.
[0030] A gearbox assembly 90 aft of the fan-turbine rotor assembly 24 provides a speed increase between the fan-turbine rotor assembly 24 and the axial compressor 22 . Alternatively, the gearbox assembly 90 could provide a speed decrease between the fan-turbine rotor assembly 24 and the axial compressor rotor 46 . The gearbox assembly 90 is mounted for rotation between the static inner support housing 42 and the static outer support housing 44 . The gearbox assembly 90 includes a sun gear shaft 92 which rotates with the axial compressor 22 and a planet carrier 94 which rotates with the fan-turbine rotor assembly 24 to provide a speed differential therebetween. The gearbox assembly 90 is preferably a planetary gearbox that provides co-rotating or counter-rotating rotational engagement between the fan-turbine rotor assembly 24 and an axial compressor rotor 46 . The gearbox assembly 90 is mounted for rotation between the sun gear shaft 92 and the static outer support housing 44 through a forward bearing 96 and a rear bearing 98 . The forward bearing 96 and the rear bearing 98 are both tapered roller bearings and both handle radial loads. The forward bearing 96 handles the aft axial loads while the rear bearing 98 handles the forward axial loads. The sun gear shaft 92 is rotationally engaged with the axial compressor rotor 46 at a splined interconnection 100 or the like.
[0031] In operation, air enters the axial compressor 22 , where it is compressed by the three stages of the compressor blades 52 and compressor vanes 54 . The compressed air from the axial compressor 22 enters the inducer section 66 in a direction generally parallel to the engine centerline A and is turned by the inducer section 66 radially outwardly through the core airflow passage 80 of the hollow fan blades 28 . The airflow is further compressed centrifugally in the hollow fan blades 28 by rotation of the hollow fan blades 28 . From the core airflow passage 80 , the airflow is turned and diffused axially forward in the engine 10 into the annular combustor 30 . The compressed core airflow from the hollow fan blades 28 is mixed with fuel in the annular combustor 30 and ignited to form a high-energy gas stream. The high-energy gas stream is expanded over the multitude of tip turbine blades 34 mounted about the outer periphery of the fan-turbine rotor assembly 24 to drive the fan-turbine rotor assembly 24 , which in turn drives the axial compressor 22 through the gearbox assembly 90 . Concurrent therewith, the fan-turbine rotor assembly 24 discharges fan bypass air axially aft to merge with the core airflow from the turbine 32 in an exhaust case 106 . A multitude of exit guide vanes 108 are located between the static outer support housing 44 and the rotationally fixed static outer support structure 14 to guide the combined airflow out of the engine 10 to provide forward thrust. An exhaust mixer 110 mixes the airflow from the turbine blades 34 with the bypass airflow through the fan blades 28 .
[0032] Referring to FIG. 3 , the fan-turbine rotor assembly 24 is illustrated in an exploded view. The fan hub 64 is the primary structural support of the fan-turbine rotor assembly 24 ( FIG. 4 ). The fan hub 64 is preferably forged and then milled to provide the desired geometry. The fan hub 64 defines a bore 111 and an outer periphery 112 . The outer periphery 112 is preferably scalloped by a multitude of elongated openings 111 . The fan hub 64 is the primary structural support of the fan-turbine rotor assembly 24 . The fan hub 64 supports the multitude of fan blades 28 , a diffuser 114 , and the turbine 32 . The diffuser 114 defines a diffuser surface 119 formed about the outer periphery of the fan blade sections 72 to provide structural support to the outer tips of the fan blade sections 72 and to turn and diffuse the airflow from the radial core airflow passage 80 ( FIG. 3 ) toward an axial airflow direction. The turbine 32 is mounted to the diffuser surface 119 as one or more turbine ring rotors 118 a , 118 b which may include a multitude of turbine blade clusters.
[0033] Referring to FIG. 4 , the fan hub 64 itself forms the multitude of inducer sections 66 . Each inducer section 66 formed by the fan hub 64 is essentially a conduit that defines an inducer passage 118 between an inducer inlet section 120 and an inducer exit section 128 FIGS. 5A , 5 B).
[0034] Referring to FIGS. 5A and 5B , the inducer sections 66 together form the inducer 116 of the fan-turbine rotor assembly 24 . The inducer inlet section 120 of each inducer passage 118 extends forward of the fan hub 64 and is canted toward a rotational direction of the fan hub 64 such that inducer inlet 120 operates as an air scoop during rotation of the fan-turbine rotor assembly 24 . Each inducer passage 118 provides separate airflow communication to each core airflow passage 80 when each fan blade section 72 is mounted within each elongated opening 114 . Preferably, each fan blade section 72 includes an attached diffuser section 74 such that the diffuser surface 119 is formed when the fan-turbine rotor assembly 24 is assembled.
[0035] FIG. 6 schematically illustrates the relationship of the angle of the last stage of the compressor rotor blade 52 (one shown) and the last stage of the compressor vanes 54 in the three stage axial compressor 22 ( FIG. 2 ) prior to communication of the airflow from the axial compressor 22 into the inducer sections 66 in the engine 10 . Referring to the compressor blade velocity triangle Bt, the compressor rotor blade 52 is angled relative to the engine centerline A to provide an angle of a relative velocity vector, Vr 1 . The velocity of the counter-rotating compressor blade 52 gives a blade velocity vector, Vb 1 . The resultant vector, indicating the resultant core airflow from the compressor blade 52 , is the absolute velocity vector, Val.
[0036] Referring to the vane velocity vector St, a stator leading edge 541 of the compressor stator 54 is angled to correspond with the absolute velocity vector, Va 1 from the compressor rotor blade 52 to efficiently receive and compress the core airflow from the compressor blade 52 . The vane trailing edge 54 t is angled relative to the engine centerline A to compress and redirect the airflow toward the inducer section 66 (one shown) as the inducer 116 rotates relative thereto at a vane absolute velocity vector, Va 1 .
[0037] The inducer inlet 120 of the inducer section 66 is angled to efficiently receive the core airflow from the vane trailing edge 54 t which flows toward the inducer section 66 at the absolute velocity vector, Va 1 from the vane 54 . The velocity of the inducer section 66 gives an inducer velocity vector, Vb 1 . Referring to the inducer velocity triangle It, the angle of the inducer 66 is selected such that the sum of the inducer relative velocity vector Vr 1 and the inducer velocity vector Vb 1 match the angle of the core airflow incoming from the compressor vane trailing edge 54 t (absolute velocity vector, Val).
[0038] It should be understood that the specific angles will depend on a variety of factors, including anticipated blade velocities and the design choices made in the earlier stages of the compressor blades 52 and compressor vanes 54 to provide a length sufficient to turn the core airflow from axial flow to radial flow while decreasing the overall length of the engine 10 . It should be understood that the axial compressor 22 may alternatively counter-rotate relative to inducer 116 as disclosed in co-pending application ______ entitled “COUNTER-ROTATING GEARBOX FOR TIP TURBINE ENGINE,” which is assigned to the assignee of the present invention and which is hereby incorporated by reference in its entirety.
[0039] Referring to FIG. 7A , the fan hub 64 retains each hollow fan blade section 72 through a blade receipt section 122 . The blade receipt section 122 preferably forms an axial semi-cylindrical opening formed along the axial length of the elongated openings 111 . It should be understood that other retention structures such as a dove-tail, fir-tree, or bulb-type engagement structure will likewise be usable with the present invention.
[0040] Each hollow fan blade section 72 includes a fan blade mount section 124 that corresponds with the blade receipt section 122 to retain the hollow fan blade section 72 within the fan hub 64 . The fan blade mount 124 preferably includes a semi-cylindrical portion to radially retain the fan blade 28 .
[0041] Referring to FIG. 7B , the inner fan blade mount 124 is preferably uni-directionally mounted into the blade receipt section 122 such as from the rear face of the fan hub 64 . The fan blade mount section 124 engages the blade receipt section 122 during operation of the fan-turbine rotor assembly 24 to provide a directional lock therebetween. That is, the inner fan blade mount 124 and the blade receipt section 122 may be frustoconical or axially non-symmetrical such that the forward segments form a smaller perimeter than the rear segment to provide a wedged engagement therebetween when assembled.
[0042] Each inducer section 66 within the fan hub 64 receives core airflow communication from the inducer passages 118 into the core airflow passage 80 and turns and diffuses the airflow through each diffuser section 74 of the diffuser 114 (also illustrated in FIG. 7C ).
[0043] It should be understood that relative positional terms such as “forward,” “aft,” “upper,” “lower,” “above,” “below,” and the like are with reference to the normal operational attitude of the vehicle and should not be considered otherwise limiting.
[0044] The foregoing description is exemplary rather than defined by the limitations within. Many modifications and variations of the present invention are possible in light of the above teachings. The preferred embodiments of this invention have been disclosed, however, one of ordinary skill in the art would recognize that certain modifications would come within the scope of this invention. It is, therefore, to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described. For that reason the following claims should be studied to determine the true scope and content of this invention. | A fan-turbine rotor assembly for a tip turbine engine includes a fan hub with an outer periphery scalloped by a multitude of elongated openings which extend into a fan hub web. Each elongated opening defines an inducer section and a blade receipt section to retain a hollow fan blade section. The blade receipt section retains each of the hollow fan blade sections adjacent each inducer section. The inducer sections are cast directly into the fan hub which minimizes leakage between each fan blade section and each of the respective inducer sections to minimize airflow leakage and increase engine efficiency. | 5 |
STATEMENT OF GOVERNMENT INTEREST
The government of the United States has certain rights in this invention pursuant to National Security Agency contract MDA-85-C-6069.
BACKGROUND OF THE INVENTION
The present invention relates to magnetically enhanced reactive ion etching (RIE) of substrates and, more particularly, to magnetically enhanced reactive ion etching of substrates of silicon wafers in bromine plasmas.
During fabrication of integrated circuits it is sometimes desirable to remove material from a wafer by etching processes. These etching processes can be characterized by their selectivity (i.e., ability to "attack" certain materials but not other materials) and by their anisotropy (i.e., ability to etch in one direction only, as opposed to undesired isotropic etching, in which material is etched in all directions at the same rate). Such etching processes can also be characterized by the spatial uniformity of the etch rate across the surface of the material to be etched.
Anisotropic etching of single-crystal and polycrystalline silicon with high selectivity to silicon dioxide has many important, recognized applications. One such application with respect to polycrystalline silicon (polysilicon) is in the area of metal-oxide-semiconductor field-effect transistor gate fabrication where oxides less than 10 nm thick must effectively stop an etch of up to 0.5 μm of polysilicon. Etching of single-crystal silicon using a silicon dioxide mask also has important applications in fabricating trenches for device isolation, trench memory cells for dynamic random access memory, and channeling and grid-support masks for ion-beam lithography.
Plasma etching of surfaces such as silicon wafers is well-established technology. Plasma etching involves a chemical reaction whereby material to be removed undergoes conversion to a volatile state in the presence of at least one chemically active species produced in a gas discharge. Reactive ion etching (RIE) processes combine the use of chemically active species with ion bombardment. In RIE processes, it is believed that ion bombardment results in damage to the surface, which is then more easily removed by the chemically active species. It should be noted that there are other explanations for the RIE mechanism as well, involving, for example, ion induced chemical reactions. Thus, in a basic sense, RIE processes constitute an attempt to strike a desired balance between purely chemical and purely physical processes. The former (e.g., dissolution) is highly selective but isotropic, while the latter (e.g., bombardment with high-energy ions) is inherently isotropic but less selective.
The desire for uniformity of etching has led to various refinements of plasma etching systems. Some such refined systems involve "tunnel" reactor designs having multiple gas inlets. Other such refined systems involve "planar" reactors in which substrates are positioned on a planar electrode. In such systems, wafers are directly in the plasma so that energetic species having high recombination rates may be used. The wafers are positioned normal to the rf field so that ion movement is both rapid and highly directional.
There is growing recognition of the importance of low-energy etching processes because high-energy etching can cause significant lattice damage to etched surfaces and oxide breakdown during gate fabrication. Furthermore, it is known that selectivity to oxide can be increased at low ion energies. Various approaches are available for achieving high etch rates at low voltages. The most commonly used approach is high-pressure "plasma" etching. Although designated a low voltage system, operating voltages in such systems well exceed 110-V. The two other approaches known to those skilled in the art are designated "magnetron" and "flexible diode" systems.
Etching of silicon with chlorine- and fluorine-based plasmas in RIE reactors is well-known and common. In both cases, selectivity to oxide has been typically found to be less than 20. Chlorine-based etching is anisotropic in the RIE mode except for very high doping concentrations, although undercutting has been detected in the plasma etching mode, even for lightly doped material. Fluorine-based etching is intrinsically isotropic and photoresist etch rates are high. Oxygen or polymer-forming gases have been added to fluorine-based etching systems to achieve anisotropic etching by suppressing side-wall erosion. Addition of polymer-forming gases tends to reduce photoresist etch rates. But, systems containing polymer-forming gases often require a large amount of maintenance and have relatively low resolution.
Other types of plasmas have been used as well, including CF 3 Br. When CF 3 Br is used in RIE systems, highly anisotropic silicon profiles have been produced. However, undercutting has been detected in plasma etching of both doped and undoped polysilicon, with relatively poor oxide selectivity. Thus, CF 3 Br is not wholly satisfactory.
Notwithstanding the many permutations of systems in the prior art, these systems have various shortcomings. None, for example, combines anisotropy for all levels of doping (n+), low resist etching rates, ultra-low silicon dioxide etching rates, ultra-high resolution, and low maintenance requirements. In addition, many of the prior art systems involve the use of multiple-gas plasma systems. Others result in low selectivity, anisotropy or uniformity. Because every system lacks one or more of these features, none is especially suitable for producing silicon stencil masks, for etching VLSI polysilicon gates, or for accomplishing other important applications.
SUMMARY OF THE INVENTION
In a broad aspect, the present invention is directed to a novel apparatus for etching a substrate, preferably a silicon wafer. The reactor is magnetically enhanced so that a wafer to be processed can be placed in the interior of the discharge ring of a planar magnetron so that the ring surrounds the wafer. In another broad aspect, the invention includes an etching apparatus with a plasma which contains substantially pure molecular bromine vapor.
In a more specific aspect, the apparatus of the present invention includes a reactor having disposed therein a means for supporting the silicon wafer to be etched, a means for causing a discharge ring of a planar magnetron to arise within said reactor and to surround the wafer, a means for causing a plasma (preferably a molecular bromine plasma) to be generated within said reactor, and a means for causing ions within said plasma to etch the silicon to be etched. The apparatus also may include a wafer that is small enough to avoid touching the discharge ring.
In another specific aspect, the process of the present invention includes the steps of supplying power between an anode and a cathode, generating a plasma (preferably a molecular bromine plasma) within a reaction chamber, placing silicon to be etched in the vicinity of said cathode, etching said silicon by ions attracted from said plasma toward said cathode, and producing a discharge ring of a planar magnetron around the silicon. The process and apparatus of the present invention are capable of operating at low energy, having a preferred -85 to -105 V cathode bias and a more preferred cathode bias of -90 V.
Accordingly, certain aspects of the present invention possess an ideal combination of anisotropy, selectivity, etch rates, and etching uniformity so as to constitute a significant advance over the prior art. Aspects and advantages of the invention are also discussed in the article by A. M. El-Masry, F-0. Fong, J. C. Wolfe and J. N. Randall, entitled "Magnetically Enhanced Reactive Ion Etching of Silicon in Bromine Plasmas", J. Vac. Sci. Technol. B 6(1), Jan./Feb., 1988, pp. 257-262, which is herein incorporated by reference.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic diagram of a magnetically enhanced RIE system;
FIG. 2 shows rf power (left) and plasma potential (right) versus self-bias voltage for a bromine plasma at 2 m Torr pressure;
FIG. 3 shows radial etch distribution measured from the center of the etch platform for 5 Ω cm, P-doped, single-crystal silicon in a bromine plasma at 2 m Torr;
FIG. 4 shows etch rates of 5 Ω cm, P-doped, single-crystal (100) silicon, HPR-256 photoresist, and PMMA (all left scale) and thermal silicon dioxide (right scale) versus self-bias voltage at 2 m Torr pressure in a bromine plasma;
FIG. 5 shows selectivity of 5 Ω cm, P-doped, single-crystal (100) silicon with respect to HPR-256 photoresist and PMMA (both right scale) and with respect to thermal oxide (left scale) versus self-bias voltage at 2 m Torr pressure in a bromine plasma;
FIG. 6 shows etch rate of P-doped polysilicon versus resistivity at -100 V bias in a bromine plasma at 2 m Torr; and
FIG. 7 is an schematic view of an alternative apparatus according to the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the drawings wherein like or similar elements are designated with identical numerals throughout the several views, and wherein shown apparatuses are not necessarily drawn to scale, a preferred embodiment of the present invention, indicated generally as 2, is shown schematically in FIG. 1. Apparatus 2 is an RIE reactor having an aluminum reaction chamber 4 in which a cathode/etch platform 6 is disposed opposite to an anode 8. The cathode/etch platform 6 is substantially covered by a fused quartz plate 10 to prevent contamination from sample 10 by sputtered aluminum during operation of apparatus 2. For measurement purposes, the rim of cathode/etch platform 6 is exposed to help provide electrical contact with plasma 14 that is in chamber 4 during operation of apparatus 2. A radio frequency (rf) power source 16 is connected to cathode/etch platform 6 to provide application of rf power thereto through a matching network 18 and blocking capacitor 20.
Chamber 4 is adapted (by having, for example, inlet port 22) to allow introduction of the bromine therein. Apparatus 2 has means for introducing a reactive etchant gas, preferably comprising pure bromine, into reaction chamber 12. This means is indicated in FIG. 1 by block element 24. This means includes such elements as a glass ampoule containing bromine, a liquid nitrogen trap, and a diffusion pump system backing up the liquid nitrogen trap, a stainless-steel needle valve to control pressure without throttling the trap, and an ambient temperature water bath to stabilize the temperature of the ampoule. Because operation of each of the foregoing elements making up the means for introducing bromine into chamber 4 are conventional, and operation and interaction of each of them is well known to those skilled in the art, further details concerning them are not provided herein. It should be understood that other reactive etchant gases can be used in accordance with the invention besides pure bromine. Etchant gases CCl 4 , CF 3 Br, C 2 F 6 , O 2 , Cl 2 , CO, CF 4 have also been found to work adequately in accordance with the invention. Thus, generally speaking, both fluorine- and chlorine-based plasmas should also work within the scope of this invention.
One aspect of the invention involves a magnetically enhanced etching apparatus having a plasma which contains molecular bromine, i.e., Br 2 . Molecular bromine helps provide many of the advantageous features of the invention, such as high selectivity to photoresist and silicon dioxide, anisotropy for heavily doped n-type silicon, and highly uniform etching. It has been discovered that any presence of CF 3 molecules would tend to reduce the effectiveness of the system and is generally to be avoided. Therefore, CF 3 Br would present problems avoided by the present invention.
Molecular bromine vapor (hereinafter may be referred to as "bromine") is a particularly advantageous feature of the invention because it can be used alone, i.e., as a single-component plasma system. The preferred plasma is substantially pure molecular bromine. Although other gases may be introduced along with the bromine, too many reactive, non-inert impurities (such as CF 3 Br or oxygen) may impair the effectiveness of the invention. For example, other gases may destroy the plasma's selectivity with respect to silicon dioxide. Preferably, the plasma contains at least 90 percent molecular bromine. This would be enough to offset most known contaminants. Even small amounts of oxygen cannot be tolerated. If oxygen is present, the plasma should have at least 99 percent, preferably 99.9 percent, bromine. The bromine can be introduced into the reactor as plasma by a method familiar to those skilled in the relevant art. For example, the bromine can be introduced by taking a bottle of bromine liquid that has a very high vapor pressure, venting the vapor into the system, and igniting a plasma using the vapor.
Referring again to FIG. 1, at the center of cathode 6 is placed a magnet such as ferrite disk magnet 26. A second magnet such as ferrite disk magnet 28 is positioned outside chamber 4, opposite magnet 26. Magnets 26, 28 thus constitute elements of a means for causing a discharge ring to arise within reactor 4, which means is an element of apparatus 2. Other means are also available, discussed, for example, in U.S. Pat. No. 4,492,610 which is hereby incorporated by reference. Magnets 26, 28 are polarized normal to the disk face and positioned with opposite field orientations. This results in a magnetic field distribution within reactor 12, indicated by curved lines or loops 30 in FIG. 1. The magnetic field of each disk magnet forms these loops 30 which leave the front face and return through the back face thereof. The field loops of each magnet are compressed by the field of the opposing magnet. Those skilled in the relevant art should appreciate that the radial component of the total field, which is zero along each disk axis, increases with radius. Accordingly, chamber 4 is bisected by an imaginary surface 32 where the total field has only a radial component. Field lines originating on the face of either magnet 26, 28 cannot cross surface 32.
An important feature of the present invention is the geometry or behavior of the field in the region 34 near the cathode/etch platform 6. The field is substantially normal to the cathode/etch platform 6 within an area surrounding the silicon wafer or other material to be etched. This area or "disc" is shown in FIG. 1 by a dashed line 36 having a certain radius. The optimum radius depends, for the most part, on the size of the wafer or etchant material. For example, it has been found that, in the illustrated apparatus, designed for 4-inch wafers, a 5-inch cathode magnet 26 would define a functional planar magnetron discharge ring. Just outside the disc formed by dashed line 36, the radial field strength increases sharply due to the fringing fields of magnet 26. The fringing fields on the periphery of magnet 26 are normal to the electric field of region 34; consequently, an intense, annular, planar "magnetron discharge" is produced.
The behavior of the field in the region 34 near cathode/etch platform 6 plays a key role in the operation of the apparatus of the present invention. The field is practically normal to cathode/etch platform 6 within a certain radius or "disc," indicated by dashed line 36. Outside the disc formed by dashed line 36, the radial field strength increases sharply due to the fringing fields of magnet 26. As the fringing fields on the periphery of magnet 26 become normal to the electric field of region 34, an intense, annular, planar "magnetron discharge" is produced. The inner diameter of this discharge can be seen in FIG. 1 to be somewhat smaller than the diameter of magnet 26.
Inside the disc 36, that is, where sample 12 would be located during operation of apparatus 2, the magnetic field is parallel to the electric field of region 34. Thus, secondary electrons emitted from the interior of cathode/etch platform 6 are magnetically focused directly through region 34 and into plasma 14. There, their trajectories follow the magnetic field lines as they bend outward toward the walls of chamber 4. Secondary electrons emitted from the center of cathode/etch platform 6 are an exception, however, as they can travel directly to the top of the plate. Visually, the discharge of the apparatus 2 of the present invention comprises a high-intensity ring close to the cathode/etch platform 6, centered on the perimeter of magnet 26, with a relatively dark interior.
From the foregoing description, those skilled in the relevant art could make and use the present invention. However, to assist those persons in understanding other aspects of the invention, certain details regarding an apparatus that has been constructed according to the present teachings and, further, certain examples involving tests performed with that apparatus are set forth below.
EXAMPLES
In accordance with the present invention, an apparatus was made comprising a reactor chamber made of aluminum, 30 cm in diameter and 10 cm in height. The diameter of the etch platform was 18.1 cm, the fused quartz plate thickness 0.16 cm, and its diameter 17.8 cm. The radio frequency power was 13.56 MHz, the nitrogen trap size was 6 inches in diameter, and the diffusion pump system was 7 inches in diameter. The base pressure, after pumping, was 1.0×10 -6 torr and the flow at 2 m torr (calculated from the rate of liquid Br 2 consumption) was 18 sccm. The radius of the sample wafer was 5 cm. Referring to the magnetic field, the magnitude of the normal field at the center of the etch platform was 150 G and the magnitude of the radial field on the etch platform above the periphery of the lower magnet was 450 G.
Samples used in the following examples (e.g., silicon, doped polysilicon, undoped polysilicon, silicon dioxide, and photoresist) were obtained commercially or fabricated by conventional IC processing techniques. High resolution patterns were defined in poly (methylmethacrylate) using a computer-controlled scanning electron microscope. Chrome etch masks were fabricated by liftoff.
All single crystal samples used in this work were 5 cm, P-doped wafers with (100) orientation. Henceforth, we shall simply refer to these as "single-crystal silicon."
A deglaze step was required to remove the native oxide on silicon prior to etching. Generally, a 30-s etch in CBrF 3 was used with a -100-V self-bias voltage at 2 m Torr. However, an exposure to a high-power (-250 V) Br 2 plasma at 2 m Torr or an HF preclean can also be used. Approximately 30 nm of silicon is etched during the CBrF 3 deglaze.
Etch rates and line profiles in silicon and polysilicon were determined by observing steps on patterned wafers in an SEM. SiO2 and photoresist etch rates were measured by ellipsometry.
EXAMPLE 1
Reactor Characterization
The dependence of power (left) and plasma potential (right) on self-bias voltage in bromine at a pressure of 2 m Torr is shown in FIG. 2. Magnetic enhancement of the plasma is manifested in the relatively low operating pressure and impedance. Without magnets, the plasma did not ignite even at 2 m Torr. At 5 m Torr, the self-bias voltage at 40 W increased from -80 to -350 V when the magnets are were removed. The plasma potential, taken as one-half of the maximum positive excursion of the cathode waveform was saturated at 35 V when the self-bias voltage reached -200 V. Generally speaking, this value is low enough to prevent serious sputtering of an aluminum chamber.
EXAMPLE 2
Etch Rates and Selectivity
The radial etch profile of the reactor for single-crystal silicon etching in bromine is shown in FIG. 3. These etch rates were obtained for single-crystal (100), 5 cm, P-doped silicon at a self-bias voltage of -100 V. The etch rate profile shows two regions: an interior disk, 10 cm in diameter, where the etch rate uniformity was better than 5%, and an outer ring where higher etch rates were obtained. The boundary between these regions marks the interior extent of the magnetron discharge ring. As power levels are increased, the magnetron discharge (which is centered on the magnet perimeter) expands, reducing somewhat the area for uniform etching. The etching results which follow all refer to wafers placed inside the disc of uniform etching.
FIG. 4 shows the etch rates of single-crystal silicon, HPR-256 photoresist, PMMA, and thermal SiO 2 versus self-bias voltage. The right axis refers to SiO 2 . The left axis refers to the other materials. The etch rate curves contain a linear segment at high bias values which, when extrapolated to the voltage axis, defines the "effective threshold" for the etch process. This threshold behavior involves more than the energy threshold in the sputtering yield, because ion current and radical concentration, which are strongly dependent upon the self-bias voltage, also play a role. The effective etch thresholds for silicon and silicon dioxide are -35 to -175 V, respectively.
FIG. 5 shows the selectivity of silicon with respect to SiO 2 (left-hand scale), and with respect to PMMA and HPR-256 (right-hand scale). The large etch threshold of SiO 2 relative to Si results in the selectivity maximum (225) at -100 V. The reduction in selectivity at lower voltages reflects the lower silicon etch rates as the silicon threshold is approached. The sharp reduction in selectivity for oxide at higher voltages implies a practical tradeoff between throughput and selectivity. Selectivity with respect to photoresist and PMMA is acceptable for most applications.
The effect of resistivity on the etch rate of polysilicon is shown in FIG. 6. Etch rate was shown to increase gradually from 55 nm/min for p-type and undoped poly to 105 nm/min for 0.8 m cm, P-doped material. This resistivity corresponded to a concentration greater than 2×10 21 /cm 3 . Note that the maximum selectivity for oxide was 450 for this particular n+ polysilicon.
EXAMPLE 3
Trench Profiles
The following patterning sequence was performed. First, a wafer was thermally oxidized to a thickness of 20 nm. A 20-nm-thick chrome mask was then formed by electron-beam (e-beam) lithograph and liftoff. A chrome pattern was subsequently transferred to the oxide by etching for 3 min in a CF 3 Br plasma at 2 m Torr pressure and -100 V self-bias voltage. The gas was then changed to Br 2 without opening the system and etching continued for an additional 50 min at 100 V. A portion of the mask pattern consisted of 0.2-μ-wide lines with 0.6-μ spaces. Spaces 0.1-μ wide and 0.04-μ wide were obtained. Etch profiles exhibited a 4° overcut taper which could be straightened by overetching. In trench etching applications this resulted in profiles which were straight for the top 20% of the trench depth and tapered toward the bottom. The effects of ion scattering between facing trench walls were only seen for widths below 0.2-μ. The side-wall taper disappeared and random deviations from vertical appeared as etching proceeded.
EXAMPLE 7
Polysilicon Gate Structures and Loading Effect
Some n-type metal-oxide semiconductor (n-mos) gate structures were fabricated in 0.8 m cm, P-doped polysilicon 0.45 μ thick on 10-nm-thick thermal oxide. Two different masks were used: (1) a chrome mask to verify that the oxide could withstand severe overetching and that anisotropy is not due to redeposited photoresist; and (2) a PMMA mask to demonstrate a practical 0.25-μ gate process using direct write e-beam lithography.
In one etching process, a sample was etched for 14 minutes in Br 2 at -100 V following an initial, 30-s, -250 V Br deglaze. This etch time corresponded to a 200% overetch of the polysilicon. A chrome-masked grating with 0.2-μ-wide lines and spaces--and with no mask undercutting or oxide penetration--was produced.
In another etching process, the -100-V Br2 process was again used. However, a -100-V, 30 CF 3 Br deglaze was used. Partial etching of a n+ -polysilicon surface resulted in a very clean final product. Silicon etch rates with the etch platform, including the magnetron, covered with silicon were found to be comparable to those on a base SiO 2 plate.
EXAMPLE 5
Bromine etching of single-crystal and polycrystalline silicon at 2 m Torr pressure was shown to be exceptionally anisotropic and selective with respect to oxide and photoresist. Loading effects were absent. A low-voltage (-100 V) process, optimized for selectively to oxide, was applied to the fabrication of polysilicon gate structures and high aspect ratio trenches. The gate etch process was shown to have 0.25-μm resolution, using an e-beam defined PMMA mask. The selectivity of polysilicon with respect to PMMA and SiO 2 was sufficiently high as not to require endpoint detection for polysilicon thicknesses up to 0.5 μ, even on sub-10-nm-thick gate oxides. Oxide breakdown was prevented by the low bias voltage. The trench process required only a 20-nm-thick oxide mask to etch 3 μ of silicon. Edge profiles showed a slight overcut taper (4°) which straightened with overetching. Trenches below 0.2 μ wide showed the effects of wall-to-wall ion scattering. The taper was absent and random waviness appeared for depths greater than 1 μ. Throughput for the trench process was quite low, but could have been increased at a sacrifice in selectivity.
It will be apparent, of course, that many modifications may be made in the above-described embodiments without departing from the scope of the invention, which is defined by the claims below. For example, referring to FIG. 7, a second cathode magnet 38 in the form of a ring may be installed surrounding magnet 26. This ring magnet 38 is preferably polarized normal to its face and installed with opposite polarity to magnet 26. The impedance of such a system may be varied by controlling the spacing between magnet 26 and magnet 30 or alternatively, by varying the magnetic fields of the magnets in the system. It should be understood, therefore, that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described. | An etching process and apparatus employ a novel magnetic enhancement means and a substantially pure molecular bromine plasma in order to perform in a desired manner for a number of important applications requiring etching of single-crystal and polycrystalline silicon. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims priority to and the benefit of Korean Patent Application No. 10-2013-0165693 filed in the Korean Intellectual Property Office on Dec. 27, 2013, the entire contents of which are incorporated herein by reference.
TECHNICAL FIELD
The present invention relates to a headlamp for a vehicle.
BACKGROUND ART
In general, lamps for a vehicle are classified into a headlamp which is installed at a front side of a vehicle, and a tail lamp which is installed at a rear side of the vehicle. The headlamps are mounted at both sides of the front side of the vehicle, and allow a driver to secure a visual field in a driving direction when the vehicle is driven at night.
Recently, the headlamp may be configured to be moved in up and down directions or in left and right directions depending on a driving environment.
For example, in a case in which the vehicle moves along a curved road, the headlamp is rotated along the driving direction so as to help the driver to secure a visual field.
Meanwhile, as illustrated in FIG. 4 , by driving a shield 30 , which may partially block light emitted from a light source 10 of a headlamp 1 , various beam patterns may be implemented.
However, a problem occurs in a case in which the shield 30 is provided inside a reflector 20 , and a shield actuator 43 , which drives the shield 30 , is provided outside the reflector 20 , or at a lens holder 50 .
First, because the shield 30 and the shield actuator 43 are separately assembled, in a case in which errors, which occur during assembly processes, are accumulated, relative positions of the shield 30 and the reflector 20 deviate from each other, and as a result, optical tolerance may be excessively generated. Since the shield actuator 43 is provided outside the reflector 20 , there is a problem in that an overall size of the headlamp is increased. Shaft connection between the shield actuator 43 and the shield 30 is incorrectly performed, and thus there is a problem in that power transmission is insufficient.
LITERATURE OF RELATED ART
Patent Literature
Korean Patent Application Publication No. 10-2012-0050271 (May 18, 2012)
SUMMARY OF THE INVENTION
Embodiments of the present invention are directed to a headlamp for a vehicle, in which power transmission between a shield actuator and a shield is smoothly performed.
Furthermore, the embodiments of the present invention are directed to a headlamp for a vehicle, which has a reduced size.
Furthermore, the embodiments of the present invention are directed to a headlamp for a vehicle, which may reduce optical tolerance.
An embodiment of the present invention provides a headlamp for a vehicle, including: a reflector which reflects light emitted from a light source; a lens which the light emitted from the light source penetrates; a lens holder which supports the lens; and a shield assembly which is provided between the reflector and the lens holder.
The shield assembly may include: a shield housing which is connected to the reflector; a shield rotation shaft which is rotatably connected to the shield housing; a shield which is provided on the shield rotation shaft; and a shield actuator which rotates the shield rotation shaft.
The shield actuator may include: an electric motor; and an output shaft which is connected to the electric motor, in which the output shaft is parallel to the shield rotation, shaft.
The output shaft may be engaged with the shield rotation shaft.
A power transmission device may be provided between the output shaft and the shield rotation shaft.
The power transmission device may include: a first gear which is engaged with the output shaft; and a second gear which is formed on the shield rotation shaft and engaged with the first gear.
The headlamp for a vehicle may further include a first frame which accommodates the reflector, in which the shield assembly is connected to the first frame.
The shield assembly may be connected to the lens holder.
The first frame may include a first connecting portion, the shield assembly may include a second connecting portion, the lens holder may include a third connecting portion, and the first connecting portion may be sequentially connected to the second connecting portion and the third connecting portion.
The first connecting portion may include a coupling projection, the second connecting portion may include a through hole, the third connecting portion may include an insertion groove, and the coupling projection may penetrate the through hole and may be inserted into the insertion groove.
The headlamp for a vehicle may further include a second frame which accommodates the first frame, in which the first frame is rotatably connected to the second frame.
The headlamp for a vehicle may further include a swivel assembly which applies rotational force to the first frame, in which the swivel assembly includes: a swivel actuator; and a swivel shaft which is connected to the swivel actuator, in which the swivel shaft penetrates the second frame and is connected to the first frame.
The first frame may include a swivel shaft connecting portion that is connected to the swivel shaft, and the second frame may include a swivel shaft through hole which the swivel shaft penetrates.
The headlamp for a vehicle may further include a housing which is connected to a vehicle body, in which the second frame is fixed to the housing.
A maximum width of the shield assembly may be equal to or narrower than a maximum width of the reflector.
According to the headlamp for a vehicle according to the embodiment of the present invention, since the shield assembly is provided inside the reflector, the shield actuator and the shield rotation shaft may be smoothly engaged with each other.
According to the headlamp for a vehicle according to the embodiment of the present invention, since the shield actuator is provided inside the reflector, a size of the headlamp may be reduced.
According to the headlamp for a vehicle according to the embodiment of the present invention, since the shield actuator is provided inside the reflector, relative positions of a reflection surface and a shield do not deviate from each other, thereby reducing optical tolerance.
The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an exploded perspective view illustrating a headlamp for a vehicle according to an embodiment of the present invention.
FIG. 2 is a partially perspective view illustrating the headlamp of FIG. 1 .
FIG. 3 is a schematic cross-sectional view illustrating the headlamp of FIG. 1 .
FIG. 4 is an exploded perspective view illustrating a headlamp for a vehicle according to the related art.
It should be understood that the appended drawings are not necessarily to scale, presenting a somewhat simplified representation of various features illustrative of the basic principles of the invention. The specific design features of the present invention as disclosed herein, including, for example, specific dimensions, orientations, locations, and shapes will be determined in part by the particular intended application and use environment.
In the figures, reference numbers refer to the same or equivalent parts of the present invention throughout the several figures of the drawing.
DETAILED DESCRIPTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Substantially the same constituent elements are indicated by the same reference numerals in the following description and the accompanying drawings, so that a repeated description will be omitted. In describing the embodiments of the present invention, well-known related functions or configurations will not be described in detail since the detailed description for the well-known related functions or configurations may unnecessarily obscure the understanding of the present invention.
It should be understood that when one constituent element referred to as being “coupled to” or “connected to” another constituent element, one constituent element can be directly coupled to or connected to the other constituent element, but intervening elements may also be present. In contrast, when one constituent element is “directly coupled to” or “directly connected to” another constituent element, it should be understood that there are no intervening elements present.
In the present specification, singular expressions include plurals unless they have definitely opposite meanings. The mean of “comprises” and/or “comprising” used in this specification does not exclude the existence or addition of aforementioned constituent elements, steps, operations, and/or device, and one or more other constituent elements, steps, operations, and/or devices.
FIG. 1 is an exploded perspective view illustrating a headlamp for a vehicle according to an embodiment of the present invention, FIG. 2 is a partially perspective view illustrating the headlamp of FIG. 1 , and FIG. 3 is a schematic cross-sectional view illustrating the headlamp of FIG. 1 .
Referring to FIGS. 1 to 3 , a headlamp for a vehicle according to an embodiment of the present invention includes a light source 100 , a reflector 200 , a lens 300 , a lens holder 400 , a shield assembly 500 , a first frame 600 , a second frame 700 , and a swivel assembly 800 .
The light source 100 refers to a device which emits light, and for example, may be a light emitting diode (LED) or a halogen lamp. However, the present invention is not limited thereto, and the light source 100 may be any other device as long as the device may emit light.
The reflector 200 serves to reflect light emitted from the light source 100 , and includes a light source mounting portion 210 , a side wall portion 220 , and a flange portion 230 .
The light source 100 may be mounted on the light source mounting portion 210 . For example, the light source mounting portion 210 may be formed in an approximately cylindrical shape.
The side wall portion 220 has a predetermined thickness, and extends from the light source mounting portion 210 so as to form an internal space 221 . A cross section of the side wall portion 220 in a lateral direction (in a Y-axis direction in the drawing) is formed in a circular shape, and a diameter of the side wall portion 220 is increased as the side wall portion 220 becomes farther away from the light source mounting portion 210 (toward an X-axis direction in the drawing). Therefore, a cross section of the side wall portion 220 in a longitudinal direction (the X-axis direction in the drawing) is formed in an approximate parabola shape. However, the present invention is not limited thereto, and the reflector may have various shapes as long as the reflector may reflect light emitted from the light source.
The flange portion 230 is formed to extend at an edge of the side wall portion 220 . The flange portion 230 may include a first flange portion 231 , and a second flange portion 233 . The first flange portion 231 and the second flange portion 233 may be provided at positions opposite to each other based on a center of the internal space 221 of the side wall portion 220 . A pair of first flange portions 231 may be disposed to be symmetric to each other. Meanwhile, an edge of the second flange portion 233 may have an approximately rectangular shape. However, the present invention is not limited thereto. On the other hand, the reflector 200 may be fixed to the first frame 600 through the first flange portion 231 , and the shield assembly 500 may be fixed to the second flange portion 233 .
The lens 300 allows light, which is emitted from the light source 100 , to penetrate the lens 300 . The lens 300 may be made of a general light transmissive material. The lens 300 is mounted on the lens holder 400 .
The shield assembly 500 is provided between the reflector 200 and the lens holder 400 , For example, the shield assembly 500 may be formed in a shape that is accommodated in the internal space 221 of the reflector 200 . That is, a width of the shield assembly 500 may be equal to or narrower than a width of the reflector 200 . For example, as illustrated in FIG. 3 , a maximum width W 1 of the shield assembly 500 may be equal to or smaller than a maximum width W 2 of the reflector 200 , that is, a length which connects both edges of the second flange portion 233 .
Meanwhile, the shield assembly 500 includes a shield housing 510 , a shield rotation shaft 520 , a shield 530 , and a shield actuator 540 .
The shield housing 510 forms an external shape of the shield assembly 500 . Each constituent element of the shield assembly 500 may be mounted or embedded in the shield housing 510 .
The shield housing 510 may be fixed to the reflector 200 . For example, the shield housing 510 may be fixed to the second flange portion 233 of the reflector 200 . The shield housing 510 is also connected to the lens holder 400 and the first frame 600 through a third flange portion 511 , and a description thereof will be described below.
The shield rotation shaft 520 is formed in a bar shape, and both ends thereof are rotatably connected to the shield housing 510 .
The shield 530 is provided on the shield rotation shaft 520 . The shield 530 may have a stepped portion that is formed at an edge of the shield 530 so as to partially block light emitted from the light source 100 . Meanwhile, the shield 530 may be formed integrally with the shield rotation shaft 520 .
The shield actuator 540 is a device that rotates the shield rotation shaft 520 . The shield actuator 540 includes an output shaft 541 , and an electric motor 543 . The output shaft 541 transmits rotational force to the shield rotation shaft 520 , and the electric motor 543 rotates the output shaft 541 . For example, the output shaft 541 may be parallel with the shield rotation shaft 520 . The shield actuator 540 may be controlled by an electronic control unit (not illustrated) of a vehicle.
Meanwhile, a power transmission device 545 is provided between the shield rotation shaft 520 and the output shaft 541 . The power transmission device 545 includes a first gear 546 , and a second gear 547 , which are engaged with each other. The first gear 546 is engaged with the output shaft 541 , and the second gear 547 is formed on the shield rotation shaft 520 . Therefore, the rotational force of the output shaft 541 is transmitted to the shield rotation shaft 520 through the first gear 546 and the second gear 547 so as to rotate the shield rotation shaft 520 . However, the present invention is not limited thereto, and the shield rotation shaft 520 and the output shaft 541 may be directly engaged with each other.
The first frame 600 includes a first main body 605 , a first connecting portion 610 , a second connecting portion 615 , and a third connecting portion 620 .
The first main body 605 may be formed in a hollow shape so as to accommodate the reflector 200 .
The first connecting portion 610 extends from the first main body 605 , and is connected to the shield assembly 500 and the lens holder 400 . A coupling projection 611 may be provided on the first connecting portion 610 .
Meanwhile, the shield assembly 500 includes the third flange portion 511 that extends from the shield housing 510 , and a through hole 513 is formed in the third flange portion 511 . On the other, hand, an insertion groove 411 is formed in a fourth flange portion 410 that extends from the lens holder 400 .
Therefore, the coupling projection 611 of the first connecting portion 610 penetrates the through hole 513 of the third flange portion 511 , and is inserted into the insertion groove 411 of the fourth flange portion 410 , such that the first frame 600 , the shield assembly 500 , and the lens holder 400 may be connected.
On the other hand, the first connecting portion 610 is rotatably connected to the second frame 700 . A description thereof will be described below.
Meanwhile, the second connecting portion 615 is a portion to which the first flange portion 231 of the reflector 200 is fixed. That is, the first flange portion 231 is fixed to the second connecting portion 615 while the reflector 200 is accommodated in, the first main body 605 , such that the reflector 200 may be fixed to the first frame 600 .
The third connecting portion 620 extends from the first main body 605 at a position opposite to the first connecting portion 610 . The first frame 600 is rotatably connected to the second frame 700 through the third connecting portion 620 . A description thereof will be described below.
The second frame 700 includes a second main body 705 , a fourth connecting portion 710 , and a fifth connecting portion 715 .
The second main body 705 may be formed in a hollow shape so as to accommodate the first frame 600 .
The fourth connecting portion 710 and the fifth connecting portion 715 extend from the second main body 705 at positions opposite to each other. The first frame 600 is rotatably connected to the second frame 700 through the fourth connecting portion 710 and the fifth connecting portion 715 . Specifically, the fourth connecting portion 710 is connected to the first connecting portion 610 of the first frame 600 , and the fifth connecting portion 715 is connected to the third connecting portion 620 .
The relative rotation of the first frame 600 with respect to the second frame 700 refers to swiveling, and this may be performed by the swivel assembly 800 . The swivel assembly 800 includes a swivel shaft 810 , and a swivel actuator 820 . The swivel shaft 810 is a rotatable power transmission shaft, and the swivel actuator 820 rotates the swivel shaft 810 . The swivel actuator 820 may include an electric motor (not illustrated).
A swivel shaft through hole 711 is provided in the fourth connecting portion 710 , and a swivel shaft connecting portion 613 is provided on the first connecting portion 610 of the first frame 600 . The swivel shaft 810 may penetrate the swivel shaft through hole 711 , and be connected to the swivel shaft connecting portion 613 . When the swivel actuator 820 is driven and the swivel shaft 810 is rotated, rotational force is transmitted to the swivel shaft connecting portion 613 . Since the swivel shaft connecting portion 613 may be rotated in the swivel shaft through hole 711 , the first frame 600 may be relatively rotated with respect to the second frame 700 .
A first pin insertion hole 716 is provided in the fifth connecting portion 715 , and a second pin insertion hole 621 is provided in the third connecting portion 620 of the first frame 600 . The fifth connecting portion 715 and the third connecting portion 620 may be rotatably connected by a connecting pin 623 that simultaneously penetrates the first pin insertion hole 716 and the second pin insertion hole 621 .
As described above, the first frame 600 and the second frame 700 are rotatably connected at two positions. That is, the swivel shaft connecting portion 613 of the first frame 600 is inserted into the swivel shaft through hole 711 of the second frame 700 , and the third connecting portion 620 of the first frame 600 is connected to the fifth connecting portion 715 of the second frame 700 .
However, if rotation axes do not coincide with each other at the two positions, the relative rotation of the first frame 600 and the second frame 700 is not smoothly performed, and related constituent components may be damaged. Therefore, the rotation axes need to coincide with each other at the two positions. That is, the first pin insertion hole 716 , the second pin insertion hole 621 , the swivel shaft through hole 711 , the swivel shaft connecting portion 613 , and the swivel shaft 810 are present on a straight line.
Meanwhile, the second frame 700 may be fixed to a housing (not illustrated). The housing is connected to a vehicle body, and therefore, the second frame 700 is fixed unlike the first frame 600 that is rotatable.
As described above, according to the embodiment of the present invention, the shield assembly 500 is provided between the reflector 200 and the lens holder 400 , that, is, inside the reflector 200 . In other words, the shield 530 and the shield actuator 540 are provided together inside the reflector 200 . As such, since the shield actuator 540 is provided inside the reflector 200 , a space may be saved, and an overall size of the headlamp may be reduced.
According to the present embodiment, since the shield rotation shaft 520 and the shield actuator 540 are provided together inside the reflector 200 , shaft connection is accurately performed, such that power transmission may be smoothly performed. According to the present embodiment, since the shield rotation shaft 520 and the shield actuator 540 are simultaneously assembled to form the shield assembly 500 , an error may be reduced during an assembly process, and optical tolerance may also be reduced.
As described above, the embodiments have been described and illustrated in the drawings and the specification. The embodiments were chosen and described in order to explain certain principles of the invention and their practical application, to thereby enable others skilled in the art to make and utilize various embodiments of the present invention, as well as various alternatives and modifications thereof. As is evident from the foregoing description, certain aspects of the present invention are not limited by the particular details of the examples illustrated herein, and it is therefore contemplated that other modifications and applications, or equivalents thereof, will occur to those skilled in the art. Many changes, modifications, variations and other uses and applications of the present construction will, however, become apparent to those skilled in the art after considering the specification and the accompanying drawings. All such, changes, modifications, variations and other uses and applications which do not depart from the spirit and scope of the invention are deemed to be covered by the invention which is limited only by the claims which follow. | A headlamp for a vehicle is provided. The headlamp includes: a reflector which reflects light emitted from a light source; a lens which the light emitted from the light source penetrates; a lens holder which supports the lens; and a shield assembly which is provided between the reflector and the lens holder. | 5 |
CROSS-REFERENCE TO RELATED APPLICATION
None.
BACKGROUND OF THE INVENTION
1. Technical Field
The present invention relates to the technology of electrical connection design and in particular, to the technology of fuse box design and power distribution circuits. More specifically, the present Invention relates to the design of a fuse box kit of the type that would be commonly used in an automobile, boat, plane, RV, or other vehicle, where it would be desirable to variably multiply the available fuse protection for applications involving equipment having high power load requirements.
2. Description of Related Art
Most vehicles have a number of electrical components such as lights, horns, stereo radios, televisions, DVD players, amplifiers, and the like. To protect the electrical circuits of the vehicles, fuses are located in the circuit for each electrical accessory. The fuses are typically positioned in a central fuse box between the electrical supply and the accessory. The main function of the fuse is to protect the wiring circuit. The fuse contains an internal conductor which provides the electrical connection between the ends of the fuse. The conductor inside the fuse is a metallic strip that has a lower melting temperature than the wiring of the circuit. The size of the conductor is calibrated so that when the failure rating of the fuse is reached, sufficient heat will be generated to melt the conductor and break the circuit (burn the fuse). In use, if an accessory fails, the increased power demand in the circuit will exceed the failure rating of the fuse, causing the fuse to bum and separate, breaking the electrical connection. If a fuse is not used, overcurrent conditions could damage circuit elements or the electric accessory, overheat the wiring and perhaps cause a fire. The condition presents a danger to both life and property.
Most automobiles have two fuse panels. The engine compartment fuse panel typically contains the fuses for protection of the electrical circuits associated with the primary vehicle functions such as cooling fans, anti-lock brake pumps, and the engine control units. An interior fuse panel is usually located under the dash on the driver's side of the vehicle, and protects the electrical circuits associated with the electrical devices inside the passenger compartment.
Different fuse designs have different rating ranges. For example, AGU fuses (glass cylinder type) are commercially available with ratings between 5 and 60 amps. MAXI fuses (blade type) are commercially available with ratings between 20 and 80 amps. The more expensive ANL fuses (wafer type) are commercially available with ratings between 60 and 300 amps. For larger loads, circuit breakers are generally required.
Improvements in electronics and microchip technology have led to an enormous increase in the development and availability of high technology accessories for use in vehicles. These devices include CD players, DVD players, televisions, computers, telephones, fax machines, custom lighting, special effects devices, high powered amplifiers, other stereo system components, and other appliances configured to operate at low voltages. The number of options far exceeds the availability, capacity, and design of factory supplied electric circuits.
Frequently, the load requirement of a desired accessory exceeds the highest rated fuse that can fit in a factory supplied fuse panel. For example, many stereo amplifiers are rated at 2,000 or even 3,000 watts. 150 amp fuses are required for these units. As a result, the consumer must either purchase a separate fuse panel for the accessory that accommodates ANL fuses, or install a circuit breaker.
In addition to a lack of space of the factory supplied fuse panels, a variety of electric devices available on the market have significantly different load requirements. As a result, some accessories may require higher current circuits with higher fuse ratings, and other accessories may require lower current circuits with lower fuse ratings. Due to the difference in fuse design capacity, the consumer is required to purchase more than one additional fuse panel.
As a result of the above described issues, retailers will normally stock two or three different power distribution panels to accommodate the different fuse designs, as well as the different sizes of AWG gage input wires.
The large custom automobile market has created a special demand for additional power distribution and high current load capable circuits. These applications require solutions that not only satisfy the electric system functionality requirements, but solutions that are cosmetically enhancing. It is common in the custom automobile industry to use gold plated fuses, and fuse panels with highly decorative architecture.
Numerous devices have been developed for the purpose of providing additional power distribution that are cosmetically attractive. Other devices have been developed which permit fuse stacking to provide a higher fuse rating by using multiple fuses on a circuit.
One such device is disclosed in U.S. Pat. No. 6,457,995 B1 issued to Brooks. The device is a distributor having a positive input terminal block separated by a riser from a negative current input terminal block.
Another device is disclosed in U.S. Pat. No. 5,628,654 issued to Lineberry, Jr., for an accessory connector adapted for insertion Into a vehicle fuse box. The connector has a pair of fuse blade receptacles for inserting additional fuse blades, such that after removing a fuse from the fuse box, the accessory connector replaces the fuse and is then located between the fuse and the fuse box.
Another device is disclosed in U.S. Pat. No. 3,744,03 issued to Dipace (3 B&D Products, Inc.), comprising a fuse block adapter, where a fuse is removed from a fuse clip and the fuse block adapter is inserted to allow for the fusing of an additional circuit.
Another device is disclosed in U.S. Pat. No. 6,457,995 B1 issued to Brooks, comprising a fuse block extender consisting of a male bus electrode and a circuit electrode positioned side by side and adapted to fit into the female electrodes of a vehicle fuse block, and of one or more accessory electrodes that connect to the bus electrode and to one or more accessories.
One disadvantage of these devices is that most are complex and expensive. Another disadvantage of these devices is that they are esthetically displacing, and thus unsuitable for customized vehicle applications. Another disadvantage of these devices is that they are limited by their principal configuration. Another disadvantage of these devices is that they are electrically unique, and require special knowledge to install and use. Another disadvantage of these devices is that they take up additional space to install. Another disadvantage of these devices is that they do not provide for use with higher load electrical appliances.
It can thus be seen that there is a need for a design of a power distribution panel that can be adapted to the various load requirements of different electrical accessories for vehicles. There is also a need for a design of a power distribution panel that can accomplish this objective while providing an esthetically enhancing architecture.
The fuse ratings and circuit descriptions are used for general Identification purposes only. The forgoing description is not intended to be instructive as to the use or safety of any particular fuse, circuit, or electrical accessory. Numerous variables, including the length and weight of the wiring are not considered here. The manufacturers recommendations for the individual electrical accessory should be consulted and followed.
BRIEF SUMMARY OF THE INVENTION
A primary advantage of the present invention is that it provides a power distribution panel kit that can be adapted to the various load requirements of different electrical accessories for vehicles. Another advantage of the present invention is that it allows for the use of less expensive fuses in higher load circuit designs. Another advantage of the present invention is that it accommodates an easily changeable configuration without any change to its esthetically enhancing architecture. Another advantage of the present invention is that it permits the addition of high load electric accessories, while eliminating the need to install additional power distribution blocks for higher fuse ratings. Another advantage of the present invention is that it provides for a broader range of circuit protection with a single fuse style.
Other advantages of the present invention will become apparent from the following descriptions, taken In connection with the accompanying drawings, wherein, by way of illustration and example, an embodiment of the present invention is disclosed.
In the preferred embodiment of the present invention, a fuse block system kit is disclosed having a nonconductive base. An electrically conductive input block is attached to the base, and a plurality of fuse clips are electrically connected to the input block. Opposite the input block, a plurality of single output blocks made of conductive material are removably attached to the base. A fuse clip is electrically connected to each single output block. Fuses are locatable in the fuse clips between the input block and the output blocks. A dual output block made of conductive material is attachable to the base in substitution of two single output blocks. In this manner, two single output blocks can be removed, and the dual output block substituted in their place. A pair of fuse clips is electrically connected to the dual output block. The resulting configuration doubles the fuse rating of the circuit without changing the size or appearance of the distribution block, and without changing the style of the fuse required.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)
The drawings constitute a part of this specification and include exemplary embodiments to the invention, which may be embodied in various forms. It is to be understood that in some instances various aspects of the Invention may be shown exaggerated or enlarged to facilitate an understanding of the invention.
FIG. 1 is an isometric view of a preferred embodiment of the present invention, disclosing a Variably Fusable Power Distribution Block kit adaptable for use in vehicles and particularty configured to receive fuses of the AGU type.
FIG. 2 is an exploded isometric view of the embodiment disclosed in FIG. 1 .
FIG. 3 is a top view of the embodiment of the invention disclosed in FIG. 1 and FIG. 2 .
FIG. 4 is a side view of the embodiment of the invention disclosed in FIGS. 1, 2 , and 3 .
FIG. 5 is an end view of the embodiment of the invention as disclosed In FIGS. 1 through 4, showing the receptacles ends of single output blocks.
FIG. 6 is a sectional side view of the embodiment of the invention as disclosed in FIG. 4, showing the members of the base connecting to input and output blocks.
FIG. 7 is an isometric view of a preferred embodiment of the present invention, disclosing the Variably Fusable Power Distribution Block of FIG. 1, whereas dual output blocks have been substituted for the single output blocks.
FIG. 8 is a top view of the embodiment of the invention disclosed in FIG. 7 .
FIG. 9 is an end view of the embodiment of the invention as disclosed in FIGS. 7 and 8, showing the receptacles ends of the dual output blocks.
FIG. 10 is an isometric view of a preferred embodiment of the present invention, disclosing a Variably Fusable Power Distribution Block kit configured to receive fuses of the MAXI type.
FIG. 11 is a top view of the embodiment of the invention disclosed in FIG. 10 .
FIG. 12 is a side view of the embodiment of the invention disclosed in FIGS. 10 and 11.
FIG. 13 is a top view of the basic embodiment of the present disclosure as disclosed in FIG. 1, showing a schematic of a circuit in which power from a power source is directed through an input connector on the input block, and being distributed to four fuses attached to single output blocks, defining four separate circuits.
FIG. 14 is a top view of the basic embodiment of the present disclosure as disclosed in FIG. 7, showing a schematic of a circuit in which power from a power source is directed through an input connector on the input block, and being distributed to four fuses attached to dual output blocks, defining two separate circuits.
DETAILED DESCRIPTION OF THE INVENTION
The following description is presented to enable any person skilled in the art to make and use the invention, and is provided in the context of a particular application and its requirements. Various modifications to the disclosed embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments and applications without departing from the spirit and scope of the present invention. Thus, the present invention is not intended to be limited to the embodiments shown, nor to a single collection of all of the elements disclosed, but is to be accorded the widest scope consistent with the principles and features disclosed herein.
FIG. 1 is an isometric view of a preferred embodiment of the present invention, disclosing a variably fusable power distribution block kit adaptable for use in vehicles, and particularly configured to receive fuses of the AGU type. In this figure, it is seen that power distribution block assembly 10 generally comprises a base 20 , an input block assembly 40 , and a plurality of single output assemblies 60 . A cover 90 encloses input block assembly 40 and single output assemblies 60 .
FIG. 2 is an exploded view of the power distribution block assembly 10 disclosed in FIG. 1 . In this view, base 20 is shown. Base 20 is preferable made of a non-conductive material, such as plastic. Base 20 has a base front 22 and an opposite base back 24 (not visible). Base 20 has a base top 26 . In the preferred embodiment, base top 26 extends outwardly, such as in the convex configuration shown in FIG. 2 . Also in the preferred embodiment, base 20 has a raised perimeter edge 28 extending upward from base front 22 . Also in a preferred embodiment, base 20 has a plurality of slots 30 located along, or near to, raised perimeter edge 28 . One or more base mounting holes 32 pass through base 20 and provide a means for attaching base 20 to the vehicle. Another feature of the preferred embodiment is the presence of locating pegs 34 formed on, and raising upward from base front 22 . A plurality of block mounting holes 36 are located on base 20 .
Still referring to FIG. 2, an input block 42 made of electrically conductive material is shown located on base 20 . In the preferred embodiment, input block 42 has an outwardly extending top 44 , such as in the convex configuration shown in FIG. 2. A terminal connector 46 is threadedly connected to input block 42 . In the preferred embodiment, one or more secondary terminal connectors 48 are threadedly connected to input block 42 . In a preferred embodiment, input block 42 has an input platform 50 with a plurality of threaded platform holes 52 .
Still referring to FIG. 2, a plurality of single output blocks 62 made of electrically conductive material are located on base 20 opposite input block 42 . Single output blocks 62 have a threaded mounting hole 64 (not visible) located on their bottom side for attachment to base 20 . In a preferred embodiment, single output blocks 62 have an output platform 66 . Also in a preferred embodiment, single output blocks 62 have a threaded platform hole 68 on output platform 64 . An output receptacle 70 is located on the side of single output block 62 opposite platform portion 64 . A terminal connector 72 is threadedly attached on top of single output block 62 . Terminal connector 72 intersects output receptacle 70 .
In a preferred embodiment, threaded connectors 80 attach a plurality of electrically conductive fuse clips 82 to input platform 50 through threaded platform holes 52 . Likewise, a threaded connector 80 attaches a fuse clip 82 to each output platform 66 through threaded platform hole 68 .
A preferred embodiment of cover 90 is further disclosed as having a face 92 and side portions 94 extending downward from face 92 . Tabs 96 extend outward from side portions 94 for engagement with slots 30 of base 20 . In a preferred embodiment, cover 90 has an outwardly extending top 98 , such as in the convex configuration shown in FIG. 2 .
FIG. 3 is top view of distribution block assembly 10 in the embodiment disclosed in FIGS. 1 and 2, with a section of cover 90 shown broken away, with tabs 96 engaging slots 30 . In FIG. 3, four ( 4 ) AGU fuses 100 are shown installed between fuse clips 82 on input block assembly 40 and fuse dips 82 on single output assemblies 60 , establishing electrical connectivity between input block assembly 40 and single output assemblies 60 .
FIG. 4 is side view of distribution block assembly 10 in the embodiment disclosed in FIGS. 1, 2 , and 3 . In FIG. 4, it can be seen that the opening beneath outwardly extending top 98 of cover 90 provides access for variable positioning of an electrical connection from a power source to terminal connector 46 , or for connection to secondary terminal connector 48 .
FIG. 5 is an end view of distribution block assembly 10 in the embodiment disclosed in FIGS. 1 through 4, showing output receptacles 70 of single output blocks 62 . In this view, it is seen that the opening formed between face 92 and side portions 94 of cover 90 provides access for locating wiring electrically connected to each output receptacle 70 of each single output block 62 , thereby defining as many as four separate fuse protected circuits in the embodiment shown.
FIG. 6 is a sectional side view of distribution block assembly 10 in the embodiment disclosed in FIG. 4 . In this view, it can be seen that terminal connector 72 intersects output receptacle 70 providing electrical and physical connectivity to circuit wiring installed in receptacle 70 . In a preferred embodiment, threaded connector 80 attaches electrically conductive fuse clip 82 to Input platform 50 through threaded platform hole 52 . In this embodiment, threaded connector 80 passes through threaded platform hole 52 so as to attach input block 42 to base 20 through threaded block mounting holes 36 . Similarly, another threaded connector 80 attaches another fuse clip 82 to output platform 66 through threaded platform hole 68 . Also in this embodiment, threaded connector 80 passes through threaded platform hole 68 so as to attach output block 62 to base 20 through threaded block mounting holes 36 .
Still referring to FIG. 6, it can be seen that locating pegs 34 of base 20 can be used to locate and secure input block 42 on base 20 . Likewise, locating pegs 34 of base 20 can be used to locate and secure output block 62 on base 20 .
FIG. 7 is an isometric view of the preferred embodiment of distribution block assembly 10 . In this view of distribution block assembly 10 , single output assemblies 60 have been removed and replaced with dual output assemblies 110 . It is seen from FIG. 7 that the overall appearance of distribution block assembly 10 remains otherwise unchanged in appearance as compared to FIG. 1 .
Each dual output assembly 110 has a dual output block 112 having a single receptacle 114 which is comparatively larger than receptacle 70 in single output block 62 , and is thus capable of accommodating a larger wire size. In the preferred embodiment, fuse clip 82 is connectable to dual output block 112 with threaded connector 80 . In the preferred embodiment for use with AGU fuses, dual output block 112 also has a platform portion 116 with a pair of platform holes 118 (not visible) in spaced apart alignment with base mounting holes 32 . Each dual output assembly 110 is substituted into the position of two single output assemblies 60 , and secured to base 20 with the same threaded connectors 80 . In this configuration distribution block assembly provides two separate fuse protected circuits, each circuit having a circuit rating of approximately twice that of the individual circuits disclosed in FIG. 1 .
In another preferred embodiment, not shown, distribution block assembly 10 comprises a combination of two single output assemblies 60 and one dual output assembly 110 , thus providing three separate fuse protected circuits.
FIG. 8 is top view of distribution block assembly 10 in the embodiment disclosed in FIG. 7, with a section of cover 90 shown broken away, with tabs 96 engaging slots 30 . In FIG. 8, two (2) AGU fuses 100 are shown installed between fuse clips 82 on input block assembly 40 and fuse clips 82 on each dual output assembly 110 , establishing electrical connectivity protected by two fuses between input block assembly 40 and output block assembly 110 . By dividing the current between the two fuses 100 , the fuse rating of the circuit is essentially doubled, without using larger fuses.
FIG. 9 is an end view of distribution block assembly 10 In the embodiment disclosed in FIG. 7, showing output receptacles 114 of dual output assemblies 110 . In this view, it is seen that the larger opening of receptacles 114 are provided to receive the larger gage wiring associated with the higher rated circuit.
FIG. 10 is an isometric view of another preferred embodiment of distribution block assembly 10 . In this embodiment, power distribution block assembly 10 is configured to receive fuses 100 of the MAXI type.
OPERATION OF THE INVENTION
In the preferred embodiment of the present invention a power distribution block assembly 10 is generally comprised of a base 20 , an input block assembly 40 , and a plurality of single output assemblies 60 . A cover 90 encloses input block assembly 40 and single output assemblies 60 . Fuses 100 are removably installed between fuse clips 82 on the input block assembly 40 and fuse clips 82 on single output assemblies 60 . Single output assemblies 60 are removably attached to non-conductive base 20 by threaded connectors 80 . In the preferred embodiment, a threaded connector 80 connects a fuse clip 82 to a single output block 62 through a threaded platform hole 68 . In the more preferred embodiment, threaded connector 80 also connects single output block 62 to base 20 through one of the threaded block mounting holes 36 .
When the vehicle owner elects to connect an electrical accessory that requires more electrical power to operate than can be provided by the largest available fuse 100 that fits in power distribution block assembly 10 , the operator can remove two single input block assemblies 40 that are adjacently located, and replace them with one dual output assembly 110 . In the preferred embodiment, the same fuse dips 82 , and threaded connectors that are used for single output assembly 40 can be used to assemble and attach dual output assembly 110 . Theoretically, even fuses 100 can be used, if properly sized to accommodate the current rating requirement of the new electrical accessory.
FIG. 11 is a top view of the basic embodiment of the present disclosure showing a schematic for a circuit in which power from a power source 120 is directed through a circuit 122 , which is connected at a wire end to terminal connector 46 on input block assembly 40 . In this configuration, four single output assemblies 60 define four separate circuits through which electrical power from power source 120 is distributed. Each of circuits 124 , 126 , 128 , and 130 have a wire end located in a receptacle 70 of a single output block 60 . The current capacity of each circuit is defined by their respective fuse 100 rating for the circuit For example, the rating of circuit 124 is the amp rating of fuse 100 a , the rating of circuit 126 is the amp rating of fuse 100 b , the rating of circuit 128 is the amp rating of fuse 100 c , and rating of circuit 130 is the amp rating of fuse 100 d.
FIG. 12 is a top view of the embodiment disclosed in FIG. 11, whereas the vehicle owner has removed all four single output assemblies 60 , and replaced them on the same base with two dual output assemblies 110 . In this configuration, dual output assemblies 110 define two separate circuits through which electrical power from power source 120 is distributed. Each of circuits 132 and 134 have a wire end located in a receptacle 70 of a single output block 60 . The current capacity of each circuit is defined as the combined rating of the respective fuses 100 connected to dual output assembly 110 . The fuses attached to a dual block assembly should have the same amp rating. Thus, the rating of circuit 132 is the sum of the amp rating of fuses 100 a and 100 b , and the rating of circuit 134 is the sum of the amp rating of fuses 100 c and 100 d.
While this invention has been described in connection with a preferred embodiment it is not intended to limit the scope of the invention to the particular form set forth, but on the contrary, it is intended to cover such altematives, modifications, and equivalents as may be included within the spirit and scope of the invention as defined by the appended claims.
The result from the use of the disclosed invention is that the vehicle owner can configure a circuit for amperage rating higher than the highest fuse rating otherwise available for a given fuse style. In addition, the present invention permits various such configurations, including the use of a dual output assembly in the center, or on either side of the power distribution block 10 . It is also seen from the foregoing that the present invention permits the user to avoid the cost, expense and trouble of purchasing additional power distribution blocks in many applications. It is also seen that the present invention preserves the aesthetic appeal of the device, even when reconfigured. It is also seen that the present invention allows for use of many of the same component parts in either configuration.
It will be appreciated by one of ordinary skill in the art that other configurations of the output blocks are possible based on this disclosure. For example, a triple output block assembly can be provided in the manner disclosed for a dual output assembly, and thus substitute in the place of three single output block assemblies. It is also recognized that numerous methods for connection and attachment of the essential elements are possible, but that the choice of such connection and attachment does not depart from the spirit and scope of the present invention. | A novel power block distribution block kit is disclosed. The blocks may use MAXI or AUG, or other types of commercially available type fuses. The present invention discloses a variably fusable power distribution block kit that permits custom configuration of the fuse to circuit relationships on a common base, and with a common cover to achieve higher circuit ratings with the same device, fuses, and component parts. | 7 |
BACKGROUND OF THE INVENTION
The present invention comprises certain hydroxamic acids as inhibitors of metalloproteases, methods for their preparation, pharmaceutical compositions containing them and intermediates used in their preparation.
Selected hydroxamic acids have been suggested as collagenase inhibitors as in U.S. Pat. No. 4,599,361 to Dickens et al. Other hydroxamic acids have been suggested as angiotensin converting enzyme (ACE) inhibitors as may be seen, for example, in U.S. Pat. Nos. 4,105,789 to Ondetti et al. and 4,154,937 to Cushman et al. Still other uses for hydroxamic acids have included the inhibition of enkephalinase as may be seen in U.S. Pat. No. 4,496,540 to Kim and EPO application No. 82402314.7 (Publication No. 0 082 088).
SUMMARY OF THE INVENTION
The compounds of this invention are selected peptide-containing hydroxamic acids which are useful as inhibitors of the activity of metalloproteases, and in particular, endopeptidases such as proteoglycan degrading enzymes and collagenase. Such inhibitory activity may be useful whenever it is desired to achieve such an effect and may also be useful in various diseases in which the activity of such enzymes has been implicated, e.g., osteoarthritis. See Woessner, et al., J. Biological Chem., Vol. 259, No. 6, pages 3633-3638 (1984); and Phadke, J. Rheumatol., Vol. 10, pages 852-860 (1983) for a discussion of the activity of these enzymes in osteoarthritis.
DETAILED DESCRIPTION OF THE INVENTION
The invention relates to hydroxamic acids of formula I:
(Formula set out on pages following Examples) I
wherein
R 1 is a hydrophobic group such as a straight or branched chain (2-7C)alkyl:
R 2 and R 3 are each an amino acid residue:
n is 1 or 2; and
A is hydrogen or a group of the formula IA: ##STR1## wherein R 4 is an amino acid residue, and the pharmaceutically acceptable acid or base salts thereof, and other suitable derivatives, for example, maleate esters.
Particular values for the compounds of formula I include those in which
R 1 is selected from a group consisting of isobutyl and n-pentyl;
R 2 and R 3 are each independently selected and are each derived from a group of amino acid residues consisting of those derived from glycine, alanine, valine, leucine, isoleucine, phenylalanine, tyrosine, tryptophan, serine, threonine, cysteine, methionine, asparagine, glutamine, lysine, arginine, glutamic acid and aspartic acid. These residues do not have an acidic terminus, but may have an acidic side chain.
R 4 is selected from a group of particular values defined for R 2 and R 3 ;
n=1; and
A is as defined above.
More particular values for R 2 and R 3 include glycine, tyrosine, tryptophan, serine, threonine, cysteine, methionine, asparagine, glutamine, lysine, arginine, glutamic acid and aspartic acid.
Preferred values include those compounds in which
R 1 is isobutyl or n-pentyl;
R 2 is leucine or valine;
R 3 is alanine or phenylalanine;
n=1;
A is hydrogen.
Particularly preferred compounds are the following: (a) (R,S)-N-[2-[2-hydroxyamino)-2-oxoethyl]-1-oxoheptyl]-L-leucyl-L-phenylalaninamide (Example 1a); (b) (R,S)-N-[2-[2-(hydroxyamino)2-oxoethyl)-1-oxoheptyl]-L-leucyl-L-alaninamide (Example 3a); (c) N-[2-[2-(hydroxyamino-2-oxoethyl]-1-oxoheptyl]-L-valyl-L-alaninamide (Example 4a): and (d) (R,S)-N-[2-[2-(hydroxyamino)-2-oxoethyl]-4-methyl-1-oxopentyl1-L-leucyl-L-phenylalaninamide (Example 5a). It is also preferred that R 2 and R 3 be of the L configuration.
It will be appreciated by those skilled in the art that certain of the compounds of formula I contain three or more asymmetrically substituted carbon atoms, for example, chiral centers exist at the carbon atoms marked with an asterisk in formula I. Such compounds may exist in and be isolated in optically active and racemic forms. It has been found that the activity of the individual isomers is not the same, it is therefore preferred to utilize the more active isomer. It has also been found that mixtures of isomers, e.g., 50/50, exhibit activity and such active mixtures are also included within the scope of the invention. It will be further appreciated by those skilled in the art that optically active forms may be prepared by resolution of the racemic form or by synthesis from optically active starting materials and that active compounds and mixtures may be determined by tests hereinafter described.
The compounds of the invention may be made by hydrogenation of a compound of formula II:
(Formula set out on pages following Examples) II
The compounds of formula II may be made by making a diacid of formula III:
(Formula set out on pages following Examples) III
such as by alkylating a trialkyl tricarboxylate of formula IIIa:
(Formula set out on pages following Examples) IIIa
where R 5 is methyl or ethyl, with subsequent hydrolysis and decarboxylation to give
a compound of formula III. Alternatively, and more preferably, a Stobbe condensation may be performed with diethylsuccinate and an aldehyde of formula R 6 CHO in strong base, where R 6 is straight or branched chain (1-6C)alkyl or phenyl, followed by hydrogenation and saponification to yield compounds of formula III.
The compound of formula III is then cyclized to obtain a compound of formula IV:
(Formula set out on pages following Examples) IV
The ring is then opened with O-benzyl hydroxylamine to form an O-protected hydroxamic acid of formula V:
(Formula set out on pages following Examples) V
The compound of formula V is then coupled with a dior tripeptide of formula VI:
(Formula set out on page following Examples) VI
(which, in turn, may be made by conventional peptide synthesis techniques) to give a compound of formula II.
The potency of compounds of the present invention to act as inhibitors of metalloproteases was determined by use of one or more of the following tests.
Chondrocyte Proteoglycanase Inhibition--For this test proteoglycan-degrading enzyme activity was measured by using the proteoglycan-polyacrylamide bead assay described by Nagase et al in Anal. Biochem., 107: 385-392 (1980). The proteoglycan subunits were prepared as follows: Frozen bovine nasal septum used in the preparation of the subunits was obtained from Pel-Freez Biologicals, Rogers, Arizona. Guanidine hydrochloride (grade 1) was obtained from Sigma Chemical Co., St. Louis, Missouri. Celite® acid-washed diatomite filter aid was supplied by Johns-Manville, Denver, Colorado. All other chemicals were of reagent or the best grade available.
The proteoglycan subunit was prepared from bovine nasal cartilage according to the procedure of Hascall et al, J. Biol. Chem., 244: 2384-2396(1969), as modified by Roughly et al, J. Biol. Chem., 255: 217-224(1981). Briefly, the cartilage was extracted with 4M guanidine hydrochloride containing 100 mM sodium acetate, 1 mM EDTA, 5 μg pepstatin/ml, 5 mM phenanthroline, and 0.02% sodium azide and adjusted to pH 6. The extraction mixture was stirred at 4° C. for 72 hr. The extraction mixture, with 5% diatomaceous earth (Hy-Flo Celite®), was filtered through a coarse sintered-glass funnel. Cesium chloride was added to produce a specific gravity of 1.50. This extract was then centrifuged for 16 hr at 129,000×gravity and 8° C. in a DuPont OTD 65 ultracentrifuge according to the procedure of Radhakrishnamurthy et al. Prep. Biochem., 10(2): 151-159 (1980). Gradient material with a specific gravity of 1.53 and greater, containing proteoglycan subunits, was retained and recentrifuged as above. Again, the gradient material with a specific gravity of 1.53 and greater was saved. The isolated proteoglycan subunits were dialized exhaustively against deionized water containing 0.02% sodium azide for 24 to 36 hr and then lyophilized.
The proteoglycan-polyacrylamide beads were prepared as described in Nagase et al., supra. The bead assay of enzyme activity was modified as follows. The assay solutions in the tubes contained 100 μl enzyme preparation and 100 μl buffer (Tris HCl, pH 7.4) or inhibitor in the buffer. Incubation with the beads was carried out at 37° C. for 6 or 20 hr. The degraded proteoglycan released from the polyacrylamide beads was determined assaying 100 μl spectrophotometrically at 535 nm with dimethylmethylene blue dye as described in Farndale et al, Conn. Tissue Res., 9: 247-248 (1982). Chondroitin sulfate was used as a standard. One unit of proteoglycan-degrading activity is defined as the amount of enzyme required to release 1 μg chondroitin sulfate/ml-hr at 37° C.
Chondrocyte Collagenase Inhibition--Acid-soluble collagen was extracted from rat tail tendon by the method of Birkedal-Hansen et al, Anal. Biochem., 115: 18-26 (1981) Rats were killed using CO 2 asphyxiation; tails were removed and stripped of skin. The tendons were removed and washed several times in cold distilled water. The salt-soluble collagen was removed by extracting the tendons twice (24 hr/extraction) in 1M NaCl, 50 mM Tris, and 5 mM CaCl 2 , pH 7.4, at 4° C. The residue was washed twice in cold distilled water and extracted with 0.5M acetic acid for 24 hr. at 4° C. Insoluble material was removed by centrifugation (48,000×gravity for 1 hr), and NaCl (5% final concentration w/v) was added to the supernatant to precipitate the solubilized collagen. Following centrifugation (10,000×gravity for 30 min), the precipitate was redissolved in 0.5M acetic acid and dialyzed against 0.02M Na 2 HPO 4 . The precipitated type I collagen was centrifuged, redissolved in 0.5M acetic acid, and lyophilized. A portion of the collagen was 14 C-acetylated using the method of Cawston et al, Anal. Biochem., 99: 340-345 (1979) to give a specific activity of 1 μCi/mg. Unlabeled and labeled collagen were mixed in a ratio of 4:1 (unlabeled: labeled) and solubilized in 5 mM acetic acid at 4° C. The collagen solution was brought to neutral pH and a final concentration of 2 mg/ml by the addition of an equal volume of 0.2M Tris base. One hundred microliters of neutralized collagen solution was dispensed into 500 -μl microfuge tubes and incubated at 35° C. overnight to allow fibril formation.
Enzyme samples were prepared as follows:
Chonodrocyte cultures. Cartilage slices were removed from the articular sufaces of 2-3 kg New Zealand white rabbits. Chondrocytes were liberated from the cartilage by sequential treatment with hyaluronidase, trypsin, and collagenase as described by Benya et al, Biochem., 16: 865-872 (1977). The cells were seeded into culture flasks at a density of 3×10 4 cells/cm 2 in Ham's Nutrient Mixture F12 (Gibco, Grand Island, NY) supplemented with 10% fetal calf serum plus 25 μg/ml gentamicin and grown to confluency (7-10 days). The monolayers were changed to serum-free Dulbecco's Modified Eagle Medium (DMEM) with 25 μg/ml gentamicin plus 30-50 units/ml human interleukin-1 (IL-1), clarified Lipolysaccharide (LPS)-stimulated P388D 1 (obtained from American Type Culture Collection, Rockville, Md.) cell supernatant, or ammonium sulfate concentrated P388D 1 cell supernatant for 3 days. The stimulated chondrocyte supernatants were dialyzed against 50 mM Tris, 5 mM CaCl 2 , 200 mM NaCl, 0.02% NaN 3 pH 7.4 (subsequently referred to as assay buffer) and stored at -20° C.
Enzyme samples to be assayed were dialyzed against an assay buffer consisting of 50 mM Tris, 200 mM NaCl, 5 mM CaCl 2 , and 0.02% NaN 3 , pH 7.4, at 35° C. Since collagenase is usally found in latent form, all samples were activated with 0.34 mM aminophenylmercuric acetate (APMA) for a minimum of 15 min at room temperature. Another dialysis was performed to remove APMA. A 100-μl aliquot of sample plus 100 μl assay buffer were added to the collagen fibrils and incubated for 18 to 24 hr at 35° C. The assays were terminated by centrifuging at 10,000×gravity for 10 min to precipitate the undigested collagen. The amount of solubilized collagen was determined by scintillation counting a 100-μl aliquot of the supernatant.
Compounds of the invention which were tested showed activity in one or both of these tests.
The following non-limiting examples are illustrative of the invention. Unless otherwise indicated:
(i) temperatures are in degrees Centigrade and procedures were carried out at room temperature, about 18°-26° C., unless otherwise indicated:
(ii) NMR spectra were determined at 250 MHz in DMSO-d 6 using tetramethylsilane (TMS) as an internal standard, and expressed as chemical shifts (delta values) in parts per million relative to TMS using the following abbreviations for designation of major peaks: s (singlet), m (multiplet), t (triplet). br (broad), d (doublet);
(iii) mass spectra data was obtained as described by the method explained in McLafferty, F. W., Interpretation of Mass Spectra (3rd ed. University Science Books, Mill Valley, California 1980) at pages 91-92.
(iv) where indicated the progress of reactions was monitored by thin layer chromatography (tlc);
(v) the following abbreviations have been used: g (gram), mg (milligram), l (liter), ml (milliliter), mmol (millimole), N (normal), M (molar), mM (millimolar), m.p. (melting point), min (minute), hr (hour), w (weight), v (volume), tlc (thin layer chromatography), R f (relative mobility in tlc), EtOAc (ethyl acetate), THF (tetrahydrofruan), MeOH (methyl alcohol), DMSO (dimethyl sulfoxide), Et 2 O (diethyl ether), EDTA (ethylenediaminetetraacetic acid), Pd/C (palladium on charcoal catalyst), CI (continuous ionization), Ci (Curie).
In addition, chemical symbols have their usual meanings unless otherwise indicated. As a conversion factor 133.3 Pascals=1 Torr. Atmospheric pressue=104,308 Pascals. Conventional abbreviations for amino acids are also used (e.g., Leu (leucine), etc.).
EXAMPLE 1
a. (R,S)-N-[2-[2-(Hydroxyamino)-2-oxoethyl]-1-oxoheptyl]-L-leucyl-L-phenylalaninamide (Formula I, R 1 =n-pentyl, R 2 =--CH 2 CH(CH 3 ) 2 , R 3 =--CH 2 φ, A=H)
A portion of the material synthesized in Example 1e (0.52 g, 0.95 mmol) was dissolved in MeOH (60 ml), and 10% Pd/C (0.18 g) was added to the solution. The stirred mixture was subjected to hydrogen at atmospheric pressure until the starting material was absent by tlc. The catalyst was removed by passing the reaction mixture through a column of diatomaceous earth (Celite®) and concentration of the filtrate gave the crude product as a solid. Recrystallization from hot MeOH/Et 2 O gave 0.18 g (39% yield) of the title compound with a m.p. of 184°-186° C.
Analysis calculated for:
C 24 H 38 N 4 O 5 .0.6H 2 O: C, 60.86; H, 8.34; N, 11.83, Found: C, 60.95; H, 8.21; N, 11.55, C, 60.85; H, 8.21; N, 11.52.
Pentylbutanedioic acid (Formula III, R 1 =n-pentyl)
A method similar to that described by Devlin, et al, J. Chem. Soc., Perkin Transactions I, page 830 (1975) was used. Sodium ethoxide was formed by the addition of sodium metal (2.25 g, 91.59 mmol) to anhydrous EtOH (150 ml) under an N 2 atmosphere. To the resultant solution was added triethyl-1,1,2-ethanetricaboxylate (obtained from Aldrich; 21 ml, 91.59 mmol) followed by dropwise addition of n-pentyl bromide (11.4 ml, 91.59 mmol). The mixture was brought to reflux and stirred overnight (19 hr). After the reaction had cooled, it was filtered and concentrated. The residue was treated with H 2 O and extracted with Et 2 O (three times). The combined organic extracts were dried (MgSO 4 ), concentrated and purified by vacuum distillation (85° C./22.66 Pascals) to yield a colorless liquid (26.37 g, 91% yield).
Analysis calculated for:
C 16 H 28 O 6 : C, 60.78; H, 8.86, Found: C, 60.80; H, 8.45, C, 60.82; H, 8.72.
All of the tricarboxylate was added to concentrated HCl (318 ml) and the resultant mixture was brought to reflux. Starting material was no longer visible by tlc after the reaction had proceeded for 44 hours. The reaction was extracted several times with a CHCl 3 / THF (7:3) mixture. Product was removed from the combined organics by extracting with 2N NaOH. The aqueous extracts were acidified (concentrated HCl) to a pH of about 3 and were extracted with CHC1 3 /THF (7:3), After the combined organic layers were dried (MgSO 4 ). removal of the solvent gave an off-white solid. Purification via gradient flash chromatography (SiO 2 , 9:1 hexane/EtOAc to 10:1 CHCl 3 /MeOH) gave 13.34 g (85%) of clean product: R f =0.62 (SiO 2 , 10:1 CHCl 3 /MeOH).
Analysis calculated for:
C 9 H 16 O 4 .0.05H 2 O: C, 57.13; H, 9.05, Found: C, 57.19; H, 9.08, C, 57.29; H, 9.26.
c. Dihydro-3-pentyl-2,5-furandione (Formula IV, R 1 =n-pentyl)
Most of the diacid synthesized in Example 1b (13.11 g, 69.69 mmol) was added to acetyl chloride (31.5 ml, 443 mmol) and the resultant mixture was brought to reflux. The starting material was consumed after 3 hours as evidenced by tlc. Removal of the volatile reaction components gave the desired product as a colorless liquid (12.40 g, 105% yield). Mass Spectrum (CI, isobutane): (M+1)=171. NMR (DMSO-d 6 ) 0.90 (3H;t, J=7), 1.29-1.40 (6H;m), 1.55-1.70 (1H;m), 1.80-2.00 (1H;m), 2.66 (1H;dt, J=10, 12.5), 3.00-3.14 (2H;m).
d. 2-[2-Oxo-2-(phenylmethoxyamino)ethyl]-heptanoic acid (Formula V, R 1 =n-pentyl)
The O-benzylhydroxylamine for this experiment was produced via the following typical procedure: O-benzylhydroxylamine hydrochloride (100 mmol, obtained from Sigma) was dissolved in H 2 O and treated with K 2 CO 3 (105 mmol). The aqueous mixture was extracted with Et 2 O, dried (MgSO 4 ) and concentrated to provide near quantitative yields of the free base.
A dry round-bottom flask under an N 2 atmosphere was charged with a solution of the anhydride from Example 1c (12.40 g, 78.76 mmol) dissolved in dry THF (150 ml). The stirred solution was then cooled with a -20° C. bath. O-Benzylhydroxylamine (9.69 g, 78.76 mmol) was added slowly dropwise via syringe pump. After addition was completed, stirring was continued for 1 hr at -20° C. Volatiles were removed by rotary evaporation and the residue was taken up in EtOAc. The organic solution was washed with 10% HCl (three times), dried (MgSO 4 ) and concentrated to give a white solid. A non-polar impurity was removed by a gradient flash column (9:1 hexane/EtOAc to 24:1 CHCl 3 /MeOH). Two recrystallizations from Et 2 O/hexane gave 6.85 g (32%) of the desired product; R f =0.58 (SiO 2 , 20:1 CHCl 3 /MeOH).
Analysis calculated for: C 15 H 21 NO 4 C, 64.54; H, 7.52; N, 5.02, Found: C, 64.74; H, 7.56; N, 5.11, C, 64.76; H, 7.66; N, 5.16.
e. (R,S)-N-[2-[2-Oxo-2-(phenylmethoxyamino)ethyl]-1-oxoheptyl]-L-leucyl-L-phenylalaninamide (Formula II R 1 =n-pentyl, R 2 =--CH 2 CH(CH 3 ) 2 , R 3 =--CH 2 φ, A=H)
A portion of the material synthesized in Example 1d (1.05 g, 3.59 mmol) was dissolved in dry THF (50 ml) under N 2 . The solution was treated with N-methyl morpholine (0.42 ml, 3.77 mmol) and the reaction mixture was then cooled with a bath at -15° C. Ethylchloroformate (0.34 ml, 3.59 mmol) was added and the reaction was allowed to stir for 1 hr at -15° C. A DMSO (15 ml) solution of LeuPheNH 2 (0.95 g. 3.43 mmol; synthesized via conventional peptide methodology) was then added dropwise. Once the addition was complete, the cooling bath was removed and the reaction was allowed to stir while warming to room temperature overnight. The mixture was diluted with Et 2 O and washed successively with H 2 O, 10% HCl (3 times), saturated NaHCO 3 , and brine. Drying and concentration gave the crude product which was purified by flash chromatography (20:1 CHCl 3 /MeOH) to provide 0.69 g (35% yield) of clean material having a m.p. of 194°-196° C.
Analysis calculated for: C 31 H 44 N 4 O 5 .0.4H 2 O: C, 66.58; H, 8.06; N, 10.01, Found C, 66.60; H, 7.92; N, 9.92, C, 66.66; H, 7.95; N, 10.01,
EXAMPLE 2
Pentylbutanedioic acid (Formula III, R=n-pentyl)
An alternative method for synthesizing the compound of Example 1b is the following multistep procedure, the first part of which may be found in Johnson et al., J. Amer. Chem. Soc., 67: 1357 (1945).
A 3-neck flask equipped with a condenser, addition funnel and an N 2 inlet was charged with potassium tert-butoxide (134.44 g, 1.10 mole; obtained from Aldrich) in dry tert-butanol (700 ml). After the solution was brought to reflux, dropwise addition of a mixture containing diethyl succinate (250 ml, 1.50 mole) and n-pentanal (106 ml, 1.00 mole) was begun. The reaction turned a deep orange. Reflux was continued for 1 hr. The reaction was cooled to room temperature and a solution of 200 ml concentrated HCl in 800 ml H 2 O was added. The organic layer was separated and the aqueous layer discarded. Concentration of the organic layer gave the crude product mixture. This was diluted with EtOAc and extracted with saturated NaHCO 3 until acid product was absent from the organic layer. The aqueous extracts were acidified to a pH of about 3 with 10% HCl and extracted with Et 2 O. The combined organic layers were dried (MgSO 4 ), rotary evaporated and vacuum distilled (101° C./33.3 Pascals) to yield unsaturated half-acid ester as a colorless oil (62.56 g, 30%). A solution of the unsaturated half-acid ester (62.14 g, 0.29 mole) in MeOH (500 ml) was added to a round-bottom flask containing 3.43 g of 10% Pd/C under N 2 . The stirred mixture was then subjected to hydrogen at atmospheric pressure until uptake was no longer observed (about 13 hr). The catalyst was removed by filtration through diatomaceous earth (Celite®) and the filtrate was concentrated by rotary evaporation. Vacuum distillation of the residue (100° C./58.65 Pascals) gave the saturated half-acid ester as a colorless oil (50.63 g, 81%). The saturated half-acid ester (50.63 g, 0.23 mole) was dissolved in EtOH (500 ml) and treated dropwise with 2N NaOH (586 ml). After standing at room temperature for 3 hr, the dark red reaction mixture was acidified to a pH of about 3 with 6N HCl and extracted with Et 2 O. The combined organic extracts were washed first with H 2 O, then with brine. Removal of volatiles followed by repeated concentration from hexane gave the crude product as a solid. Recrystallization from room temperature Et 2 O/hexane gave 33.76 g (77% yield) of white solid which had the same properties as the compound of Example 1b.
EXAMPLE 3
a. (R,S)-N-[2-[2-(Hydroxyamino)2-oxoethyl]-1-oxoheptyl]-L-leucyl-L-alaninamide (Formula I, R 1 =n-pentyl, R 2 =--CH 2 CH(CH 3 ) hd 2, R 3 =--CH 3 A=H)
Using the procedure described in Example 1a, hydrogenation of the compound synthesized in Example 3b gave 0.26 g (96% yield) of the title compound with a m.p. of 134°-136° C.
Analysis calculated for: C 18 H 34 N 4 O 5 .0.50H 2 O: C, 54.66; H, 8.91; N, 14.17, Found: C, 54.95; H, 8.77; N, 13.59, C, 54.95; H, 8.82; N, 13.62.
b. (R,S)-N-[2-[2-oxo-2-(phenylmethoxyamino)ethyl]-1-oxoheptyl]-L-leucyl-L-alaninamide (Formula II, R 1 =n-pentyl, R 2 =--CH 2 CH(CH 3 ) 2 , R 3 =--CH 3 , A=H)
Following the procedure outlined in Example 1e, a portion of the material synthesized in Example 1d (1.03 g, 3.50 mmol) was coupled with LeuAlaNH 2 (0.67 g, 3.34 mmol; LeuAlaNH 2 was synthesized via conventional peptide methodology). Workup followed by flash chromatography (15:1 CHCl 3 /MeOH) gave 0.36 g (22% yield) of the title compound; Rf=0.26 (SiO 2 , 15:1 CHCl 3 /MeOH).
Analysis calculated for: C 25 H 40 N 4 O 5 : C, 63.04; H, 8.40; N, 11.76, Found: C, 63.18; H, 8.52; N, 11.10, C, 63.31; H, 8.47; N, 11.03.
EXAMPLE 4
a. N-[2-[2-(Hydroxyamino-2-oxoethyl]-1-oxoheptyl]-L-valyl-L-alaninamide (Formula I, R 1 =n-pentyl, R 2 =--CH(CH 3 ) 2 , R 3 =--CH 3 , A=H)
Using the procedure described in Example 1a, hydrogenation of the compound produced in Example 4b gave 0.35 g (0.77 mmol) of the title compound with a m.p. of 218°-220° C.
Analysis calculated for: C 17 H 32 N 4 O 5 : C, 53.93; H, 8.70; N, 14.79, Found: C, 54.04; H, 8.59; N, 14.49, C, 53.89; H, 8.56; N, 14.34.
b. N-[2-[2-oxo-2-(phenylmethoxyamino)ethyl]-1-oxoheptyl]-L-valyl-L-alaninamide (Formula II, R 1 =pentyl, R 2 =--CH(CH 3 ) 2 . R 3 =--CH 3 , A=H)
Using the procedure described in Example 1e, a portion of the material synthesized in Example 1d (0.96 g, 3.27 mmol) was coupled with ValAlaNH 2 (0.58 g, 3.13 mmol; ValAlaNH 2 was synthesized via conventional peptide methodology). Workup followed by flash chromatography (14:1 CHCl 3 /MeOH) gave 0.42 g (27% yield) of the title compound, R f =0.34 (SiO 2 , 14:1 CHCl 3 /MeOH).
Analysis calculated for: C 24 H 38 N 4 O 5 : C, 62.36; H, 8.22; N, 12.11, Found: C, 62.32; H, 7.97; N, 12.03, C, 62.23; H, 8.17; N, 11.97.
EXAMPLE 5
a. (R,S)-N-2-[2-(hydroxyamino)-2-oxoethyl]-4-methyl-1-oxopentyl]-L-leucyl-L-phenylalaninamide (Formula I, R 1 =--CH 2 CH(CH 3 ) 2 , R 2 =--CH 2 CH(CH 3 ) 2 , R 3 =--CH 2 φ, A=H
Using the procedure of Example 1a, hydrogenation of the compound from Example 5e (0.53 g, 0.99 mmol) with subsequent recrystallization from hot MeOH/Et 2 O gave 0.24 g (54% yield) of the title compound with a m.p. of 193°-195° C.
Analysis calculated for: C 23 H 36 N 4 O 5 .0.06H 2 O: C, 60.20; H, 8.15; N, 12.21, Found: C, 60.05; H, 7.73; N, 11.97, C, 60.44; H, 7.99; N, 12.08
b. 2-(2-Methylpropyl)butanedioic acid (Formula III, R 1 =--CH 2 CH(CH 3 ) 2 )
The procedures used in this example were the same as those described in Example 1b, except isobutyl bromide was used instead of n-pentyl bromide in the alkylation step. Thus, 22.6 g (91.6 mmol) of triethyl-1,1,2-ethanetricarboxylate were alkylated with 12.6 g (91.6 mmol) of isobutyl bromide. Subsequent distillation at 80° C. and 26.66 Pascals gave 23.7 g (86% yield) of an intermediate alkylated tricarboxylate.
Analysis calculated for: C 15 H 26 O 6 .0.4H 2 O: C, 58.09; H, 8.72, Found: C, 58.30; H, 8.22, C, 58.00; H, 8.37.
Hydrolysis of the tricaboxylate by refluxing it with concentrated HCl gave 10.1 g (74% yield) of purified title compound; R f =0.38 (SiO 2 , 9:1 hexane/EtOAc).
Analysis calculated for: C 8 H 14 O 4 : C, 55.19; H, 8.04, Found: C, 55.03; H, 8.45, C, 55.27; H, 8.49.
c. Dihydro-3-(2-methylpropyl)-2,5-furandione (Formula IV, R 1 =--CH 2 CH(CH 3 ) 2 )
A major portion of the diacid synthesized in Example 5b (9.92 g, 57.00 mmol) was added to acetyl chloride (26 ml, 362.5 mmol) and the resultant mixture was brought to reflux. After 3 hr, the reaction was allowed to cool and the volatiles were removed to give the desired product as a colorless liquid (8.74 g, 98% yield); R f =0.63 (7:3 hexane/EtOAc). Mass spectrum (CI, isobutane)-(M+1)=157. NMR (DMSO-d 6 ): 0.85 (3H; d, J=6), 0.89 (3H; d, J=6), 1.53-1.65 (3H; m), 2.73 (1H; dd, J=6.8, 18), 3.05 (1H; dd, J=9, 18), 3.20-3.40 (1H; m).
d. 4-Methyl-2-[2-oxo-2-(phenylmethoxyamino)ethyl]-2-pentanoic acid (Formula V, R 1 =--CH 2 --CH(CH 3 ) 2 )
The anhydride (8.66 g, 55.47 mmol) formed in Example 5c was reacted with O-benzylhydroxylamine (6.83 g, 55.47 mmol) using the procedure described in Example 1d. A non-polar impurity was removed by gradient flash chromatography (9:1 hexane/EtOAc to 24:1 CHCl 3 /MeOH). Recrystallization of the resultant off-white solid using Et 2 O/hexane gave 6.30 g (41% yield) of a white solid; R f =0.43 (SiO 2 , 24:1 CHCl 3 /MeOH). Mass spectrum (CI, isobutane) - (M+1)=280.
Analysis calculated for C 15 H 21 NO 4 : C, 64.54; H, 7.52; N, 5.02, Found: C, 64.43; H, 7.29; N, 5.09, C, 64.74; H, 7.46; N, 5.12.
e. N-[4-Methyl-2-[2-oxo-2-(phenylmethoxyamino)ethyl]-1-oxopentyl]-L-leucyl-L-phenylalaninamide (Formula II, R 1 =--CH 2 CH(CH 3 ) 2 , R 2 =--CH 2 CH(CH 3 ) 2 , R 3 --CH 2 φ, A=H)
Using the procedure described in Example 1e, a portion of the material synthesized in Example 5d (1.25 g, 4.49 mmol) was coupled with LeuPheNH 2 (1.19 g, 4.28 mmol; LeuPheNH was synthesized via conventional peptide methodology). Workup followed by flash chromatography (14:1 CHCl 3 /MeOH) gave material that was recrystallized from MeOH/H 2 O to yield 0.53 g (22% yield) of the title compound with a m.p. of 208°-210° C.
Analysis calculated for: C 30 H 42 N 4 O 5 .0.3O: C, 66.27; H, 7.89; N, 10.30, Found: C, 66.30; H, 7.88; N, 10.29, C, 66.32; H, 7.86; N, 10.43.
EXAMPLE 6
a. 2-(2-Methylpropyl)butanedioic acid (Formula III, R 1 =--CH 2 CH(CH 3 ) 2 )
An alternative method of making the title compound previously made in Example 5b is as follows. A procedure analogous to that described in Example 2 was followed using isobutyraldehyde instead of n-pentanal. Isobutyraldehyde (45 ml, 0.5 mole) was condensed with diethyl succinate (125 ml, 0.75 mole) employing potassium t-butoxide (67.22 g, 0.55 mole) as base in tert-butanol (500 ml) solution. After distillation at 105°-107° C. and 133.3 Pascals, workup gave 81.71 g of an intermediate unsaturated half-acid ester.
Analysis calculated for: C 10 H 16 O 4 : C, 60.02; H, 8.00; Found: C, 60.00; H, 8.10; C, 60.14; H, 8.08.
A portion of this intermediate compound (21.10 g, 0.11 mole) was hydrogenated (1.25 g 10% Pd/C in 250 ml MeOH) at atmospheric pressure. Workup gave a saturated half-acid ester as a second intermediate as a colorless oil in quantitative yield (21.69 g).
Analysis calculated for: C 10 H 18 O 4 : C, 59.43; H, 8.91, Found: C, 59.10; H, 8.71, C, 58.86; H, 8.71.
Saponification of this colorless oil (20.37 g, 0.10 mole) with 2N NaOH and recrystallization from Et 2 O/hexane at room temperature gave 13.55 g (77% yield) of the title product as a white solid having the same properties as the compound of Example 5b.
Example 7
a. N-[2-[2-(Hydroxyamino)-2-oxoethyl]-4-methyl-1-oxopentyl]-L-valyl-L-alaninamide (Formula I, R 1 =--CH 2 CH(CH 3 ) 2 , R 2 =--CH(CH 3 ) 2 , R 3 =--CH 3 , A=H)
Following the procedure described in Example 1a, the material from Example 7b (0.14 g, 0.31 mmol) was hydrogenated and purified by flash chromatography (10:1 CHCl 3 /MeOH) to give 83 mg (74% yield) of the title compound.
Analysis calculated for: C 16 H 30 N 4 O 5 .0.5H 2 O: 52.30; H, 8.50; N, 15.25, Found: C, 52.00; H, 8.03; N, 15.22, C, 51.97; H, 8.11; N, 14.90.
b. N-[4-Methyl-2-[2-oxo-2-(phenylmethoxyamino)ethyl]-1-oxopentyl]-L-alaninamide (Formula II, R 1 =--CH 2 CH(CH 3 ) 2 , R 2 =--CH(CH 3 ) 2 , R 3 =--CH 3 , A=H)
Using the procedure described in Example 1e, a portion of the material synthesized in Example 5d (1.0 g, 3.58 mmol) was coupled with ValAlaNH 2 (0.67 g, 3.58 mmol; ValAlaNH 2 was made using conventional peptide synthesis techniques). Workup followed by flash chromatography (10:1 CHCl 3 /MeOH) gave 0.14 g (9% yield) of the title compound; R f =0.29 and 0.33 (SiO 2 10:1 CHCl 3 /MeOH).
EXAMPLE 8
a. N-[2-[2-(Hydroxyamino)-2-oxoethyl]-4-methyl-1-oxopentyl]-L-leucyl-L-phenylalanyl-L-leucinamide (Formula I with A=Formula IA, R 1 =--CH 2 CH(CH 3 ) 2 , R 2 =--CH 2 CH(CH 3 ) 2 , R 3 =--CH 2 φ, R 4 =--CH 2 CH(CH 3 ) 2 )
Employing the procedure described in Example 1a, the compound obtained in Example 8b (0.53 g, 0.81 mmol) was subjected to deprotection and flash chromatographed to give 85.2 mg (19% yield) of the title compound with a m.p. of 227°-229° C.
Analysis calculated for: C 29 H 47 N 5 O 6 .0.02H 2 O: C, 61.61; H, 8.45; N, 12.38, Found: C, 61.77; H, 8.17; N, 12.14, C, 61.54; H, 8.02: N, 12.06.
N-[4-Methyl-2-[2-oxo-2-(phenylmethoxyamino)ethyl]-1-oxopentyl]-L-phenylalanyl-L-leucinamide (Formula II with A=Formula IA, R 1 =--CH 2 CH(CH 3 ) , R 2 =--CH 2 CH(CH 3 ) 2 , R 3 =--CH 2 φ, R 4 =--CH 2 CH(CH 3 ) 2 )
Using the procedure described in Example 1e, a portion of the compound produced in Example 1d (1.03 g, 3.68 mmol) was coupled with LeuPheLeuNH 2 (1.37 g, 3.51 mmol; LeuPheLeuNH 2 was made using conventional peptide synthesis techniques). Workup followed by repeated flash chromatography yielded 0.53 gm (22% yield) of the title compound with a m.p. of 213°-215° C.
Analysis calculated for: C 36 H 53 N 5 O 6 .0.6H 2 O: C, 65.23; H, 8.24; N, 10.56, Found: C, 65.34; H, 8.19; N, 11.0, C, 65.21: H, 8.45; N, 11.08. ##STR2## | This invention provides a series of novel hydroxamic acids of formula I which are useful as inhibitors of metalloproteases such as endopeptidases. | 2 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates generally to mobile telecommunications networks. More specifically, the present invention relates to transmitting signals between end-user clients and application servers for troubleshooting and other useful purposes.
[0003] 2. Background of the Invention
[0004] As the integration between mobile services and internet services develops, mobile operators are providing more internet-like services. Since customers are downloading increasingly large amounts of data from mobile networks, there is a need for more sophisticated error reporting and customer services.
[0005] Internet usage is becoming more widespread and computers are becoming increasingly smaller and portable. Thus, there exists a growing vacuum for wireless handheld devices that can access multimedia and online resources. This vacuum is being filled from various directions in the form of faster data-transfer protocols, stronger standardization between technologies, increasingly powerful wireless devices, and large amounts of investment by cellular operators in ensuring that their networks can implement these technologies. What opportunities were once solely in the realm of the internet are now opening up in the cellular or mobile world. Already, media file downloading has become a lucrative business model. With the increasing availability of MP3 files, JPG images, and other resources for download, more cellular telephones are being used as portable music players, photo albums, video cameras, game consoles, etc. As the internet and cellular worlds merge, there is a growing need for smoother communication between devices and networks, and for cellular operators to be on top of things in terms of understanding common problems and providing better customer service.
[0006] In response to this growing integration, mobile telephone technology has come a long way from the 1st generation of analog cellular phones, known as 1G. The second generation, 2G, was based on 100% digital transmissions. This allowed for the transfer of both voice and data, including SMS and email. The most enduring standard of 2G has been the Global System for Mobile Communications, or GSM. GPRS technology was added to the GSM framework in 2.5G (en route to today's 3G). This paved the road for increasing use of the Internet over cellular phones. GPRS allowed packet-switching, allowing more efficient data transfer than 2G's circuit switching. Alongside 3G came increased bandwidth/frequencies for data-only, with lower incremental cost.
[0007] In defining the 3G standard, The 3rd Generation Partnership Project (3GPP) has standardized several network, signaling, and transport protocols. A good example of one such standardization is the network architecture of the IP Multimedia system (IMS). IMS basically describes a system by which mobile operators can offer and charge for discrete services that are usually available on the internet, alongside current services being offered. This architecture works with any packet-switching network, is IP-based, and therefore has tremendous potential for services like VoIP, push-to-talk, videoconferencing, IM, presence information, etc. An example of a standardized signaling protocol is the Session Initiation Protocol (SIP). SIP allows two elements in a network to find each other and open lines of communication easily, and is a significant part of IMS.
[0008] Currently the system is not as robust as a proper IP-based system such as the internet. If for any reason a customer is dissatisfied with a mobile internet service, it is not an easy task to report the problem. There has been a boom in the “push” part of the content delivery business, but two-way transfer between the customer and the mobile operator is still underdeveloped.
[0009] When dealing with media resources, the mobile operator should ideally be aware of any problems in their resource database. Typical examples of these problems include, but are not limited to, poor quality media, faulty/corrupted files, packet losses in transmission, mislabeled or non-existent media resources, offensive media resources and bottlenecks in the system.
[0010] Unfortunately, the symptoms of these problems are most often experienced on the customer's end. At this point, the mobile operator will benefit if the customer can report these symptoms to the operator. However, at present, this process is laborious and is cost and time-inefficient in many ways. This is because there are additional costs to the customer; the customer usually has to call the mobile operator, and wait to be routed to the correct person; the customer cannot provide all precise relevant information required, such as media type, exact time, error details, etc.; and Interactive Voice Response (IVR) systems are frustrating to use for most customers. There are additional costs to the operator as well, including: special equipment to monitor media resources 24/7; increased staff to handle customer complaints; and overall lower level of customer satisfaction.
[0011] In summary, telephone or communications companies cannot provide high quality service when they cannot fix small problems quickly. Thus, there is a need for a simple and efficient method to inform mobile operators about potential problems with their media resources; a method that requires almost no work at all on the customer's part, and that could actually incentivize the customer to report the problem.
SUMMARY OF THE INVENTION
[0012] The present invention addresses the need to detect bad media resources by providing a system for customers to “tag” the bad media in real-time. Depending on the transmission protocol being used, this tag can be received and analyzed by the mobile operator within a short amount of time (e.g., seconds) after the customer initiates the process. Upon receiving a bad media file or hearing poor voice quality, the customer can initiate a tagging process. The customer's mobile device will send a preliminary tag via the cellular network to the Application Server (AS). The AS will retrieve any additional related information from a resource database, and will store this report in an event log or trouble log. The data in this log can be analyzed and a troubleshooting sequence can be initiated.
[0013] The customer owns a mobile device that is equipped with error-reporting. When the customer detects a bad resource, such as a defective or missing media file, or poor voice quality, they may initiate a tagging process by typing in a predefined code. This tag can be initiated immediately or within a certain window of time after the customer detects the bad resource. Depending on the signaling protocol being used, the tag will traverse various elements in the cellular network before reaching its destination. One exemplary embodiment uses a Session Initiation Protocol (SIP) tag that will traverse various proxy servers before reaching a SIP-enabled AS. The AS then pulls up the related resource from a database, possibly invoking a Media Resource Function (MRF). The AS then compiles an error report with all relevant information, and stores this report in a trouble log for further analysis. The receipt of a tag could also be trigger an automated diagnostic routine. At this point, the customer is informed via the network that the problem is being solved.
[0014] Real-time tagging eliminates the need for any further research into when or where the problem occurred. Tagging these resources happens in real-time so all relevant data regarding the incident is available. Tagging can create a useful database of events with accurate data for improved troubleshooting of bad media, thereby saving the operator endless time and resources in diagnosing the problem.
[0015] In one exemplary embodiment, the present invention is a network system for communicating error details to a telecommunications operator. The network system includes a wireless device capable of transmitting a message over a cellular network; a unit that is capable of receiving the message; and a unit that is configured to combine the message with additional information and compile a report.
[0016] In another exemplary embodiment, the present invention is a network system for communicating error details regarding voice and multimedia resources to a telecommunications operator. The network system includes a wireless device capable of transmitting a message over a cellular network; one or more proxy servers to route the message; a unit that is capable of receiving the message; a database containing information related to the voice or media resource; a unit that is capable of retrieving information from said database; and a unit that is configured to combine the resource details with an error message to compile an error report.
[0017] In yet another exemplary embodiment, the present invention is a method for identifying problematic media resources in real time on a wireless communication network. The method includes recognizing problematic resources on the client side; assembling a preliminary report containing error details; sending preliminary report over the network to an application server; collecting related information from a media resource database; combining related information with a preliminary report to compile an error report; and using said error report to diagnose the problem.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] FIG. 1 shows a high-level schematic of a cellular device communicating an error with the cellular network, according to an exemplary embodiment of the invention.
[0019] FIG. 2 shows a flowchart outlining the tagging process according to an exemplary embodiment of the invention.
[0020] FIG. 3 shows a schematic of a process using SIP messaging to report a bad resource, according to an exemplary embodiment of the present invention.
[0021] FIG. 4 shows a schematic of a process using USSD messaging to report poor voice quality, according to an exemplary embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0022] The present invention addresses the need to increase awareness of faulty media resources by allowing the recipient of the resource to “tag” the media instantly. As shown in the system architecture of FIG. 1 and flowchart of FIG. 2 , once the Client 110 recognizes a bad resource 100 from the cellular network, the Client 110 may initiate the tagging process. Depending on the signaling and transport protocol being used, the tag makes its way 120 through the cellular network before reaching the respective Application Server (AS) 130 that controls the resource. The AS 130 may then retrieve any associated information about the resource from a resource database 135 , possibly invoking the Media Resource Function (MRF) in the process. The AS 130 will then compile a tag consisting of the initial tag and the additional information, and may store the tag in a trouble log 140 for further analysis.
[0023] The client may be any cellular telephone, wireline telephone, PDA, smartphone, PC-Card, or any other device that can receive data from a cellular network. The resource itself may have been transmitted via any current or future data-transfer protocol used in cellular networks, e.g., GPRS, CDMA, EDGE, 1xEVDO, etc. The resource may be streamed over the network or downloaded directly to the client. The data may be free or the client may have been billed for access to the resource. Alternatively, the resource could simply be voice audio from another client, or voicemail, or audio from a VoIP session.
[0024] Whatever form it may take, the resource may be “bad” for a number of reasons. For instance, the client may have received the wrong media resource, which could mean that a resource file is mislabeled on the server. Even if the correct clip is loaded, the file itself could be damaged or corrupted. Alternatively, there could also be problems in the transmission of the file for a variety of reasons such as packet losses, delay, jitter, or some other technical problem. Perhaps the media resource is incompatible with the client device or model. Also, with telecom companies offering such services as personalized greetings, ringing tones, or playback tones that are configured by another party, there is a risk that the client may find the clip offensive. For improved customer satisfaction, it would be vital to be able to tag these bad or offensive resources for further troubleshooting or investigation.
[0025] In any case, a bad resource has to be recognized as such before it can be tagged. In one exemplary embodiment, the customers themselves recognize a bad resource and can tag it immediately or within a preset window of time after the resource has been identified. The customer would download, view, or listen to the clip, decide that there is a problem with the clip, and then initiate the tagging procedure. This could likely be the case for mislabeled or potentially offensive resources. Alternatively, the bad resource could be recognized by an automated detection system that is part of the client. The detection system could be software or hardware based, and may detect errors in the data stream, or inconsistencies between the resource data and what the client requested. This program could inform the client user that the media resource is faulty or mislabeled, and could also initiate the tagging process on behalf of the user.
[0026] Once the resource has been identified, the next step is to create a preliminary “tag” to transmit to the cellular operator. This preliminary tag will contain all relevant information that is available at the time including, but not limited to: date and time; client phone number; client hardware or cell phone model; information on the media resource being tagged; and error code or details if available (missing data, corrupted stream, packet loss, bad filename, etc.).
[0027] The actual content of the tag will depend on the signaling protocol that will be used to transmit the tag. In one exemplary embodiment, as shown in FIG. 3 , the client uses the Session Initiation Protocol (SIP) to transmit the tag. SIP is in increasing use today for a number of processes, especially in the VoIP realm. In this exemplary embodiment, the user could initiate the tagging process by typing in a predefined command, or the automated system could initiate the tagging process by assembling and transmitting the tag. In either case, the SIP-enabled client composes a SIP message with encoded details listed above and transmits the tag to the Media Resource Function (MRF) 333 or the Application Server (AS). An added extension to the protocol, SIP Instant Messaging and Presence Leveraging Extensions (SIMPLE), contains a MESSAGE function that can transmit instant messages with any text or binary content. Alternatively, the SIP-enabled client will initiate a session with the MRF/AS via SIP, and then use RTP or any equivalent protocol having similar functions to transmit the body of the tag to the MRF/AS. The benefits of using SIP are that it is flexible, there is no need for any intelligence (apart from routing) between the client and the server, and the technology is scaleable, in that any upgraded applications (including JAVA apps) on either end will be supported in the future.
[0028] In another exemplary embodiment shown in FIG. 4 , the client may use an Unstructured Supplementary Service Data (USSD) code to report a bad resource. The client is either informed of or programmed with a predefined code for reporting an error. USSD codes may be appropriate for reporting a poor quality voice call. In such a case, the user would punch in the USSD code and the phone number dialed, or the client's own phone number. The code could look like this: *123*cell# where *123 is the predefined error code and cell# is the client's cellular number or the dialed party's number. Alternatively, a USSD command could be used as a front-end for launching a text-based menu application that allows the client user to interactively select more details about the bad media. Advantages of using USSD include the fact that USSD capability is built into most GSM networks and is available to almost all existing GSM handsets, with no handset or SIM card upgrade necessary.
[0029] However, this invention is not restricted to currently existing protocols. One skilled in the art should be able to apply this concept to numerous existing and future protocols ranging from the PSTN SS7 protocols to SIP-like protocols involving instant messaging over IP networks.
[0030] The client 110 then sends the tag out 120 to the application server 130 . On its way to the application server, the tag is routed through relevant network elements depending on the protocol being used. In the embodiment shown in FIG. 3 , solid arrows 321 show a data transfer, dashed lines 322 show a SIP message. The SIP tag 320 will traverse multiple proxy servers 325 before it reaches the AS 331 and/or MRF 333 . Once the tag reaches its SIP-enabled destination, there will be direct communication between the Client 310 and the MRF/AS 333 / 331 , at which point more data can be transferred between the two using an appropriate transport protocol. Alternatively, the SIP message itself may contain the relevant information which is then processed by the MRF/AS 130 .
[0031] In the USSD exemplary embodiment shown in FIG. 4 , the message will reach a USSD server 425 via one or more Mobile Switching Centers (MSCs) and a Home Location Register (HLR) 424 . The HLR routes the message to the Application Server or the Service Control Point 430 that manages the resource, thus opening a session 450 between the Client 410 and the AS/SCP 430 . Alternatively, the HLR can route the message to the AS/SCP via a USSD Server 425 .
[0032] The AS 331 is programmed to recognize the tag, combine it with additional data, and create a trouble log for all bad media events. Within the AS/MRF package 331 / 333 , media resources are handled by the MRF 333 which consists of a Media Resource Function Controller (MRFC) and a Media Resource Function Processor (MRFP). The MRFC acts as a control layer which co-ordinates operations between the AS and the MRFP. When the application server requires media processing it sends a request to the MRFC which in turn manages the MRFP to invoke the media processing required for media transcoding, anchoring and streaming. The media resources are stored on a database 135 , 335 , e.g., a song or ring tone database.
[0033] In the exemplary embodiment shown in FIG. 3 , the AS 331 instructs 336 the MRF 333 to retrieve specific information on the problem resource from the resource database 335 . This could include the file type, size, version, attributes, DRM info, etc. The AS 331 then combines this information along with the information from the Client's tag to compile an error report. This report is stored in an event log, or trouble log 140 , 340 . The advent of software-based standalone IMS-compliant MRF servers adds to the flexibility of the system since the MRF can logically be placed at any point in the network chain. For instance, the client 310 can interact 334 with the MRF 333 to bolster its tag before submitting the tag 350 to the AS 331 . Alternatively, the Client 310 can submit the tag to the MRF 333 , which will add additional information before submitting the tag to the AS 331 . The AS 331 will finally compile the report, adding any additional information, and store it in the trouble log 340 .
[0034] At this point the bad media is properly tagged, and all tags are stored in a trouble log 140 , 340 . The trouble log 130 , 340 provides a number of uses. The stored tag can be analyzed by a human who can review patterns of errors and troubleshoot them with accurate information. For instance, a certain model of mobile telephone may have trouble loading JPG images from the MRF. Perhaps members of area code 571 may be unable to receive personalized ring-back tones. These problems can be detected quickly with real-time tagging. Apart from a human review, the creation of a tag could initiate an automated quality check routine for the tagged resource. This automated routine, for example, could compare the tag with existing tags in the trouble log, and notify the administrator if the number of events for a certain resource reaches a pre-designated number x, or if pre-designated n number of subscribers encounter bad calls during peak hours. Many such scenarios are evident to one skilled in the art after consideration of the present disclosure and are thus within the scope of the present invention.
[0035] Meanwhile, the AS 130 can send a message 150 to the client 110 , confirming receipt of the tag and that troubleshooting has begun. This message could be sent via SMS, voicemail, SIP email, or any equally user-friendly method. Also, since consumers are typically billed for certain media resources (e.g., MP3, JPEG, etc.), the AS/MRF could also refund money to users based on the problem with the media, or send them a message to please try again.
[0036] One of the many advantages of the present invention is that it enables media tagging to occur in real time. Faulty media can be tagged as soon as it is detected by the client (human or electronic). The client, AS, and MRF work together to get as much information as is relevant at the time the tagging is initiated. Mobile operators will also benefit from giving their subscribers access to these user-friendly customer services. Real-time tagging of bad media is an ideal way for operators to gain operational efficiency in their contact centers, with subscribers able to resolve day-to-day requests themselves. It also improves levels of customer service as IVR systems are sometimes an impersonal method of interacting with customers and indeed can result in poor customer service with subscribers being kept on hold for a lengthy period of time.
[0037] The foregoing disclosure of the exemplary embodiments of the present 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. Many variations and modifications of the embodiments described herein will be apparent to one of ordinary skill in the art in light of the above disclosure. For example, the above configuration as shown and described may be used on WiFi and WIMAX networks as well as cellular using the above, similar or equivalent configuration. The scope of the invention is to be defined only by the claims appended hereto, and by their equivalents.
[0038] Further, in describing representative embodiments of the present invention, the specification may have presented the method and/or process of the present invention as a particular sequence of steps. However, to the extent that the method or process does not rely on the particular order of steps set forth herein, the method or process should not be limited to the particular sequence of steps described. As one of ordinary skill in the art would appreciate, other sequences of steps may be possible. Therefore, the particular order of the steps set forth in the specification should not be construed as limitations on the claims. In addition, the claims directed to the method and/or process of the present invention should not be limited to the performance of their steps in the order written, and one skilled in the art can readily appreciate that the sequences may be varied and still remain within the spirit and scope of the present invention. | The present disclosure provides systems and methods for tagging or identifying bad, faulty or objectionable media resource files in real time, as the media is playing, by users who are exposed to the media. The tagging is simple to use and easy to remember, allowing for increased use of the tagging process to identify, correct and replace bad, faulty or objectionable media. | 7 |
DESCRIPTION
BACKGROUND OF THE INVENTION
This invention relates to a method of sewing a buttonhole, more particularly, to an improved method in which the final stitching is made in the forward direction and in which buttonholes which are perpendicular to the edge of a garment may be initiated on the end of the buttonhole nearest the edge of the garment.
The buttonhole produced on presently known electronically controlled sewing machines utilizes a travelling buttonhole foot in which a button determines the location of stops which actuate, through a paddle arrangement, switches in the sewing machine to initiate the next series of stitches for the buttonhole. In these prior art sewing machines the buttonhole sequence includes (1) making a first bar (2) implementing narrow bight cording stitches on the left side in the forward feed direction, (3) completing the second bar, (4) finishing the left side with wide bight covering stitches in the reverse direction, (5) implementing the narrow bight cording stitches on the right side in the forward direction, and (6) making wide bight covering stitches in the reverse feed direction over the right side cording stitches. This system was developed and is successful in eliminating the need for adjusting balance, i.e., having the stitches on one side of the buttonhole have the same appearance as the stitches on the other side thereof. However, since the final stitches are accomplished in the reverse direction, they do not have the same appearance as stitching in the forward direction. Since most of the stitching of sewing machines is accomplished in the forward direction, considerable care and attention is devoted to insure that the forward stitch presents a good appearance. For example, in some machines there is a greater tendency to "halo" in the reverse direction, that is to have an extra amount of top thread between stitches, which condition is not evident in the forward direction.
Simply reversing the sequence for making the buttonhole so that the cording stitches are accomplished in the reverse direction and the final covering stitches in the forward direction is not a solution in as much as a problem could occur in the making of a buttonhole which is perpendicular to the edge of a garment. In such a buttonhole, it is desirable that the initial bar tack begin adjacent the edge of the garment since any variation which may take place in the length of a buttonhole will not be as noticeable on the side away from the edge of the garment as it would be next to the edge. Thus, to position the work material adjacent an operator as is usual, and to reverse the above sequence would initiate the buttonhole on its inner side and not adjacent the edge.
What is required is a method for making a buttonhole having the seemingly adverse requirements for accomplishing the final stitches in the forward direction and at the same time having the initial bar tack in a forward direction with respect to the final bar tack.
SUMMARY OF THE INVENTION
The above desired requirement is achieved in a buttonhole method in which the initial bar tack of a buttonhole disposed perendicular to the edge of a garment may be initiated adjacent to the garment edge, and followed immediately by a first row of straight stitches in the forward feed direction down the middle of the buttonhole. Alternatively, the needle bar latching mechanism may be activated during this first row of sraight stitches so as to make them long basting stitches which may be easily removed. Thereafter, the second bar tack may be completed and the cording stitches may be effected in the reverse direction thereby to complete the covering stitches in the forward direction.
BRIEF DESCRIPTION OF THE DRAWING
The foregoing will be more readily apparent upon reading the following description in conjunction with the drawings in which:
FIG. 1 is a perspective view of the sewing machine in which the method according to this invention may be practiced;
FIG. 2 is an elevation of a garment utilizing buttonholes perendicular to an edge thereof;
FIG. 3 is a closer view of one of the buttonholes shown in FIG. 2;
FIG. 4 is a table of encoded data for producing a buttonhole pattern in accordance with the method of this invention; and
FIG. 5 is a representation of the buttonhole pattern formed from the data illustrated in FIG. 4.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the drawings, FIG. 1 illustrates a sewing machine indicated generally at 10 having a control panel 12 illustratively of the type utilizing a continuous planar element such as a glass panel to which circuitry is applied as by deposition or the like to provide controls sensitive to the touch of an operator's finger. Indicated on the control panel 12 are touch sensitives areas having respective representations of various stitch patterns which may be automatically sewn by the sewing machine 10.
The sewing machine 10 is provided with the capability of sewing either a large buttonhole, indicated by the large buttonhole representation 14 on the control panel 12, or a small buttonhole, indicated by the small buttonhole representation 16 on the control panel 12. When a buttonhole pattern is to be sewn, a buttonhole presser foot 18 is installed on a sewing machine 10. The buttonhole presser foot 18 includes a fixed rear stop member 20 and an adjustable front stop member 22, the distance therebetween defining the length of the buttonhole pattern being sewn, as determined by the size of button inserted between an anchor element 24 and a buttonhole gauging element 26. The sewing machine 10 further includes a switch mechanism including a lever arm 28 terminating in a paddle 30 at its lower end. The other end of the lever arm 28 is received by openings in a pair of spaced lugs 32 formed on one end of a lever 34. The lever arm 28 may therefore be selectively raised and lowered by an operator, the operator lowering the lever arm 28 so that the paddle 30 is intermediate the stops 20 and 22 during the formation of a buttonhole pattern.
The lever 34 is pivoted at 36; and at the end opposite the lugs 32 has a pin 38 mounted thereon for cooperation with an electrical switch member 40. Manipulation of the paddle 30 on both ends of the buttonhole causes actuation of the electrical switch member 40, which actuation is fed to the electronic control unit for the sewing machine in order to initiate the next of a sequence of steps in the formation of a buttonhole. For further information with respect to the operation of the electrical switch member 40 and the electronic package of the sewing machine, the reader is referred to the U.S. Patent Appl. Ser. No. 928,939, filed on July 28, 1978, now U.S. Pat. No. 4,159,688 and assigned to the assignee of the present invention, the disclosure of which application is hereby incorporated by reference herein.
As mentioned above, in the background comments, the method of the present invention is concerned with the manufacture of a buttonhole which does not require any balance adjustment and in which the final covering stitches are effected in the forward direction. It was further indicated that this method should be effected in all cases, including those cases where the buttonholes are formed perpendicular to the edge of a garment. In such a situation, it is desirable that the initial stitches for the buttonhole should be formed adjacent the edge of the garment so that any variation in the length of the buttonhole would be spaced from the edge of the garment and thereby rendered less noticeable. Referring to FIG. 2, there is shown such a garment 44 in which buttonholes 46 are spaced on the front thereof along an edge 48. A single buttonhole 46 is shown in greater detail in FIG. 3. The buttonhole slit 50 is arranged perpendicular to the edge 48 of the garment 44. With any arrangement of this fashion, it is preferable that the initial stitching be a bar tack closest to the edge 48 of the garment so as to be able to provide close operator control over the spacing "A" of the buttonhole from the edge of the garment. Thus, as has been repeated above, any variation in the length of the buttonhole 46 will take place inwardly of the garment and away from the edge 48 thereof so as to make any error less perceptible by reason of spacing from the edge 48.
Referring now to FIG. 4, there is shown encoded data for the formation of a large buttonhole pattern, such encoded data being stored in a memory as is explained in the above referenced application. FIG. 5 is a representation of the large buttonhole pattern formed from the data illustrated in FIG. 3. The encoded data stored in the memory comprises a twelve bit digital word for each stitch as is shown under the code column of FIG. 4. In each of these digital words, the five left most bits corresponds to the feed increment for the immediately following stitch, the next five bits corresonds to the bight position for the present stitch, the eleventh bit is a control bit which may be utilized to decrement the address counter so as to address the previous word again, and the twelfth bit is a control bit which may be used to initiate basting. For an explanation of a basting stitch mechanism which may be implemented by the twelfth control bit the reader is referred to the U.S. Pat. No. 3,872,809 of Adams et al which is hereby incorporated by reference herein. By use of the eleventh bit, a side bar of infinite length may be sewn from two code words which form a "loop", the exit from which is controlled by operation of the switch member 40 at both ends of the buttonhole pattern.
Referring to FIG. 5, each lateral bight actuator position and corresponding incremental feed displacement which resulted in a stitch in the large buttonhole pattern coded as shown in FIG. 4 is represented by a small open circle, with the stitch number closely adjacent thereto. The first ten stitches form the upper bar with the tenth stitch in center needle position. Stitches eleven and twelve are straight, or basting, stitches in center needle position having a small feed increment, with the twelfth stitch having the eleventh control bit of one to indicate that the previous stitch should be return to until the paddle 30 is actuated by the front stop member 22 to initiate the second bar tack, stitches 13 through 21. The encoded data of FIG. 4 shows a high ("1") for the twelfth bit of stitches eleven and twelve, indicating that these are skipped stitches where the work material is advanced without stitch formation. The lack of stitching is indicated in FIG. 5 by an X. The line or stitching would be terminated by actuation of the electrical switch member 40. Stitches 22, 23 and 24 initiate the first layer of cording stitches in the reverse direction on the left side of the buttonhole, the stitch 24 having a control bit value of one to indicate that the previous stitch should be return to until the paddle 30 is actuated by the rear stop member 20. Thereupon, the cording stitch is overlaid by stitches 25 and 26 effected in the forward direction, stitch 26 having a control bit indicating a return to the previous stitch coordinates until the paddle 30 is actuated by the front stop member 22. The right side cording stitches and overlying stitches are effected in the same manner as the left side stitches, the last actuation of the paddle 30 by front stop member 22 causing the sewing machine to cease further stitching and feeding operations. Thus, the final overlay stitches for the left and right side bars are sewn in the same forward direction, control of feed balance is not necessary to provide for the formation of uniform and consistent buttonhole, and the buttonhole is initiated with a bar tack lying adjacent the edge 48 of a garment 44 to be stitched.
Accordingly, there has been disclosed an improved method of sewing a buttonhole pattern. It is understood that the above-described method is merely illustrative of the application of the principles of this invention, and it is only intended that this invention be limited by the scope of the appended claims. | A method of forming a buttonhole including two spaced apart rows of zig zag stitches so that each row is formed in a like manner with the final overlaying stitches accomplished in the forward direction and which may be initiated by a barring stitch adjacent the edge of the garment followed by a straight stitch down the cutting space to the opposite end of the garment. | 3 |
The invention concerns a spinning machine with at least one spinning station, which station possesses a feed drum driven by a single drive, a disintegrating roll, a rotor, a withdrawal roll and a spool roll.
EP 0 385 530 discloses such a spinning machine, in which the feed drum of each spinning position of an open-end spinning machine is driven by means of a stepping motor. A control system with an associated computer regulates the corresponding stepping motor in each spinning machine in accord with its direction of rotation, its speed of rotation and the angular position of the drive, and thereby also the feed drum. A control system for each of the stepping motors is advantageous, so that the necessary precision in regard to the feed of the fiber band is assured.
In the conventional spinning machines, normally, the rotating elements which follow the feed drum in the direction of the band movement, for example, the rotor, are centrally driven by means of motors provided on an end of the spinning machine. In order to achieve the necessary correlation of the speed of rotation, for instance, of the feed roll, the withdrawal roll, and the spool roll, electrically controlled, mechanical gear drives are provided. By this means, each spinning station can produce constant yarn quality where yarn diameter and strength are concerned. Such gear drives possess, however, a great number of points of abrasion, which give rise to a relatively substantial demand of expense and maintenance time. Additionally, a relatively large startup momentum can be attributed to these gear drives. Where the necessary electrical control is concerned, considerable costs are involved in its wiring and installation.
OBJECTS AND SUMMARY OF THE INVENTION
Thus, it is a principal object of the present invention to make available a spinning machine in which is made possible a simple, and therefore precise, drive of the individual rotational elements of a spinning station. Additional objects and advantages of the invention will be set forth in part in the following description or may be obvious from the description, or may be learned through practice of the invention.
This purpose is achieved by the spinning station exhibiting additional single drives, respectively for the withdrawal roll, and/or the spool roll, and/or the waxing roll, and the rotational ratios of the single drives being set to specification.
The advantage of the invention can be particularly seen in that—besides each feed drum—an individual drive has been assigned to each withdrawal roll, and/or to each spool roll, and/or to each waxing roll. Since the rotational ratios of the individual drives of each spinning station can be specified, an optimized correlation in regard to synchronization, operational life, and rotational speed is assured. Furthermore, by means of the installation of the single drives, expensive and damage-prone gear drive construction is avoided, which otherwise would extend itself over the entire length of the spinning machine. Another advantage is that a very low degree of nominal torque is present with this single drive because of the small friction to which the individual drives are exposed. Especially, no torsional delays occur upon the startup of the respective rotational elements of the spinning stations, which are situated remotely from the central motor. A single drive, for example, is also advantageous for the withdrawal roll so that the spinning startup process is made substantially easier, since this roll upon spinning startup is driven in reverse direction.
Advantageously, one of the individual drives serves as a lead motor. This lead motor has a specified guiding rotational speed or a specified guide frequency, which is related to the rotational speed of at least one single drive, and preferably, where multiple drives are concerned, the rotational speeds of all other single drives. In this manner, the RPM of all other single drives refers back to the lead drive and the rotational speeds of the other drives can thus be preset.
Advantageously, the feed motor of the feed drum is designated to be the guide motor, since, first, it rotates at a relatively low rotational speed (1-150 RPM) and, second, it must hold to the currently set rotational speed with great precision. Even small deviations lead to an undesirable variation of the set values of the thread to be spun. Although the single drive of the feed drum is chosen as the lead motor, this is not dependent upon the guidelines of other drives. Much more, the rotational speed of the lead motor can be directly and precisely adjusted. Because of the mentioned achievable exactness of its rotational speed, with an appropriate ratio control, a uniform torque for the other single drives is possible in all RPM ranges.
In an advantageous manner, for each spinning station, only one power control center for the regulation and the supply of electrical current to the individual drives need be provided. This design has the advantage of having the electronic circuitry only installed once, since this serves all individual drives per spinning station. On this account, long cable hook-ups from a central network, which then must run along the entire spinning machine, are no longer necessary.
In order to further reduce extensive constructional work and wiring, the power control center is placed on or near one of the individual drives. For instance, the power control center is screwed within or onto the housing of the feed drum. For the wiring thereof, corresponding borings are made through the housing. From the power control center, the additional control and power lines run to the other individual drives. The power control center can be provided at any of the other individual drives. For the eventual placement, the spatial conditions in the spinning station must be taken into consideration, so that, besides space saving, maintenance and cleaning services can be carried out with good accessibility.
The rotational speed of the other single drives in relation to the lead motor is advantageously effected by a frequency generator. For instance, there is respectively one frequency generator between the power control center to which the lead motor is connected and each of the single drives which is to be controlled. Alternatively, a single frequency generator can be furnished which transmits the rotational speed commands based on those of the lead motor to the individual drives by means of a frequency divider.
The invention allows a very fine subdividing of the motor rotation speed for the lead motor and/or the individual drives to be undertaken in micro-stepping, so that practically feedback-free operation of this motor is possible.
It is particularly advantageous to design at least one of the single drives as a stepping motor. Stepping motors have the advantage that they possess only very few parts and certainly no gear drives which are susceptible to wear and tear. Further, stepping motors possess the advantage that, while maintaining high efficiency, a relatively small inertial moment is in effect. Their shafts start to rotate without inrush current to the motor, that is, the motor can be quickly accelerated. In addition, stepping motors can be simply and precisely controlled and react very quickly to control commands. Further, stepping motors can be brought up to top speed on a continuous basis and in addition can be driven in the reverse direction. In regard to the economics, the stepping motor has no decisive disadvantage as compared to the synchronous motor. By the use of a stepping motor for the feed drum, this motor is preferable in a range of 1 to 150 RPM and can be run at a nearly constant torque.
Especially at a paraffin roll, which serves for the waxing of the yarn before the windup on the spool, the installation of a stepping motor is advantageous. Conventionally, for the drive of a paraffin roll, a synchronous motor is selected. Because of the mechanical gear drive in such a motor, relatively great frictional forces must be overcome during startup of the roll. To this purpose, the motor customarily calls for excess current. This characteristic increases the complexity of the control, i.e., the constant monitoring. Alternatively, a larger motor could be selected, which, however, would have an even greater demand for current at startup. By means of the selection of a stepping motor, all these problems are prevented.
For the feed drum of each spinning station, the use of a stepping motor is likewise advantageous, as has already been made clear by the above description of the state of the technology. In particular, the doing away with extensive and failure-prone gear drives as well as acquiring precision of the RPM even in the lower rotational speed ranges are advantages to be valued.
This precision permits running the spinning station as a “stand alone machine” with the corresponding demands for a high degree of precision. The installation of stepping motors for the individual drive of the withdrawal roll and/or the spool roll—if such individual drives are provided—is, because of the above mentioned grounds, also advantageous.
In a particularly preferred embodiment of the invention, the stepping motor for the paraffin roll is regulated by the lead stepping motor of the feed drum. A power control center delivers a signal through the frequency generator and over a line to the stepping motor for the paraffin roll. Should the feed drum, for instance, be turning at 10 RPM and if the frequency generator is set at a rotational speed ratio of 5:1, then the paraffin roll rotates at 2 RPM. Advantageously, in such an operation, small micro-step subdivisions per motor revolution are not necessary.
Advantageous developments of the invention are characterized by the features of the subordinate claims.
BRIEF DESCRIPTION OF THE DRAWING
In the following, an embodiment of the invention will be more closely described with the aid of the drawing.
FIG. 1 shows a spinning station 1 of a spinning machine schematically presented.
DETAILED DESCRIPTION
Reference will now be made in detail to the presently preferred embodiments of the invention, one or more examples of which are shown in the figures. Each example is provided to explain the invention, and not as a limitation of the invention. In fact, features illustrated or described as part of one embodiment can be used with another embodiment to yield still a further embodiment. It is intended that the present invention cover such modifications and variations.
A plurality of similar spinning stations 1 are customarily placed beside one another, which, in composite, form the spinning machine. In FIG. 1, the spinning station 1 possesses—in the direction of travel of the fiber band or sliver—in sequential array:
a feed drum 2 ;
a disintegrator 3 ;
a rotor 4 ;
a withdrawal roll 5 ;
a paraffin roll 6 ;
an auxiliary paraffining block 8 ; and
a spool roll 7 .
Emerging from a (not shown) draw frame, the fiber band or sliver B makes its way to the feed drum 2 , which is circumferentially and axially corrugated and which conveys the fiber band B to the disintegrator roll or combing roll 3 .
Equipped with circumferential comblike teeth 13 , the disintegrator 3 separates the band B into individual fibers. By means of a funnel shaped conduit 14 , and under a suction, the stream of individual fibers enters the rotor 4 . The rotor 4 rotates, by means of a central drive for all rotors of the spinning machine, at speeds of rotation exceeding 100,000 RPM and spins the fibers into a yarn F. This yarn F is subsequently removed from the rotor by the withdrawal roll 5 together with roll 11 which exerts a rolling pressure on the withdrawal roll 5 . After this removal, the yarn F is guided to frictional contact with the paraffin block 8 and then is transported by the paraffin roll 6 , which turns at a low rate of speed. Continuing in motion, the yarn F is finally wound onto a spool 10 which is axially supported by a rotating core 9 . The spool 10 lies with its own weight against the spool roll 7 and obtains its rotational energy therefrom.
The feed drum 2 is connected to an individual drive 12 designed as a stepping motor. In the embodiment presented in the figure, the withdrawal roll 5 is connected with a single drive 15 , the paraffin roll 6 with a single drive 16 and the spool roll 7 with its own drive 17 . The stepping motor for the feed drum 2 in the depicted embodiment is designed as a lead motor with a specifically set lead RPM or with a given lead frequency. This lead RPM determines the RPM of the remaining drives 15 , 16 and 17 . The speed of rotation of the motor 12 is controlled by a power control center 20 , which with the input of either the specified lead frequency or the lead speed of rotation of the motor 12 , transmits the respective frequencies (or RPM's) to the individual motors 15 , 16 , 17 by means of electrical lines 23 , 25 , 27 . Between the power control center 20 and the individual drives 15 , 16 , 17 , respectively, a frequency generator 22 , 24 , 26 is inserted into the circuit for the purpose of presetting to specific values the speeds of rotation of the single drives 15 , 16 , 17 .
The individual drives 15 , 16 , 17 can be designed as stepping motors, in like manner to the individual drive 12 of the feed drum 2 . Stepping motors have, in such an application, among other preferable features, the advantage that they possess no gear drives subject to wear and tear. The supposed disadvantage that stepping motors must be directly controlled is countered by the invention by simply providing a single power control center by means of which the rotational ratios derived from either the frequency or the RPM of a lead motor can be preset to specified values.
The single power control center 20 serves likewise for the power distribution to the individual drives 12 , 15 , 16 , 17 . Not only does this allow space to be saved within the spinning station, but also the expenditure in wiring and attendant labor within a spinning station can be held at a low level. The power control center 20 is, for instance, placed directly on the stepping motor 12 of the feed drum 2 , possibly screwed onto the housing thereof. From this point, the electrical control lines 23 , 25 , 27 run respectively to the other individual drives associated with the given spinning station. The frequency generators 22 , 24 , 26 can likewise by incorporated into the power control center.
In an embodiment which is not illustrated, another motor is proposed as lead motor instead of the individual motor 12 of the feed drum 2 . In the case of additional, not shown, embodiments, besides the individual motor 12 for the feed drum 2 , simply one or two of the individual drives 15 , 16 , 17 are foreseen as the drive of one or two of the rolls 5 , 6 , 7 . The possibility exists of using an individual drive 16 designed as a stepping motor for the paraffin roll 6 and controlling this drive by the individual drive 12 for the feed roll 2 by means of the power control center 20 as well as with the frequency generator 24 . In this manner, no problems will arise upon startup of the paraffin roll 6 , since lesser frictional force is to be overcome than is the case with the conventionally employed synchronous motor. Thus, an otherwise necessary, heavy inrush current at startup for the paraffin roll can be avoided. Moreover, a single drive 16 for the paraffin roll 6 shows little wear, so the maintenance and cleaning expenses are kept at a low level.
It will be appreciated by those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope of the invention. It is intended that the present invention include such modifications and variations as come within the scope of the appended claims and their equivalents. | In a spinning machine with at least one spinning station possessing a feed drum, driven by a single drive, a disintegrator, a rotor, a withdrawal roll and a spool roll, provisions have been made that the spinning station has an additional single drive respectively for the withdrawal roll and/or the spool roll and/or a paraffin roll. The speed of rotation ratio of the single drives can be preset to specified values. | 3 |
FIELD OF THE INVENTION
[0001] The field of this invention relates to suspending one tubular in another, especially hanging liners which are to be cemented.
BACKGROUND OF THE INVENTION
[0002] In completing wellbores, frequently a liner is inserted into casing and suspended from the casing by a liner hanger. Various designs of liner hangers are known and generally involve a gripping mechanism, such as slips, and a sealing mechanism, such as a packer which can be of a variety of designs. The objective is to suspend the liner during a cementing procedure and set the packer for sealing between the liner and the casing. Liner hanger assemblies are expensive and provide some uncertainty as to their operation downhole.
[0003] Some of the objects of the present invention are to accomplish the functions of the known liner hangers by alternative means, thus eliminating the traditionally known liner hanger altogether while accomplishing its functional purposes at the same time in a single trip into the well. Another objective of the present invention is to provide alternate techniques which can be used to suspend one tubular in another while facilitating a cementing operation and still providing a technique for sealing the tubulars together. Various fishing tools are known which can be used to support a liner being inserted into a larger tubular. One such device is made by Baker Oil Tools and known as a “Tri-State Type B Casing and Tubing Spear,” Product No. 126-09. In addition to known spears which can support a tubing string for lowering into a wellbore, techniques have been developed for expansion of tubulars downhole. Some of the techniques known in the prior art for expansion of tubulars downhole are illustrated in U.S. Pat. Nos. 4,976,322; 5,083,608; 5,119,661; 5,348,095; 5,366,012; and 5,667,011.
SUMMARY OF THE INVENTION
[0004] A method for securing and sealing one tubular to another downhole facilitates cementing prior to sealing and allows for suspension of one tubular in the other by virtue of pipe expansion techniques.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] FIGS. 1 - 4 are a sectional elevation, showing a first embodiment of the method to suspend, cement and seal one tubular to another downhole, using pipe expansion techniques.
[0006] FIGS. 5 - 11 a are another embodiment creating longitudinal passages for passage of the cementing material prior to sealing the tubulars together.
[0007] FIGS. 12 - 15 illustrate yet another embodiment incorporating a sliding sleeve valve for facilitating the cementing step.
[0008] FIGS. 16 - 19 illustrate the use of a grapple technique to suspend the tubular inside a bigger tubular, leaving spaces between the grappling members for passage of cement prior to sealing between the tubulars.
[0009] FIGS. 20 - 26 illustrate an alternative embodiment involving a sequential flaring of the inner tubular from the bottom up.
[0010] FIGS. 28 - 30 illustrate an alternative embodiment involving fabrication of the tubular to be inserted to its finished dimension, followed by collapsing it for insertion followed by sequential expansion of it for completion of the operation.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0011] Referring to FIG. 1, a tubular 10 is supported in casing 12 , using known techniques such as a spear made by Baker Oil Tools, as previously described. That spear or other gripping device is attached to a running string 14 . Also located on the running string 14 above the spear is a hydraulic or other type of stroking mechanism which will allow relative movement of a swage assembly 16 which moves in tandem with a portion of the running string 14 when the piston/cylinder combination (not shown) is actuated, bringing the swage 16 down toward the upper end 18 of the tubular 10 . As shown in FIG. 1 during run-in, the tubular 10 easily fits through the casing 12 . The tubular 10 also comprises one or more openings 20 to allow the cement to pass through, as will be explained below. Comparing FIG. 2 to FIG. 1, the tubular 10 has been expanded radially at its upper end 18 so that a segment 22 is in contact with the casing 12 . Segment 22 does not include the openings 20 ; thus, an annular space 24 exists around the outside of the tubular 10 and inside of the casing 12 . While in the position shown in FIG. 2, cementing can occur. This procedure involves pumping cement through the tubular 10 down to its lower end where it can come up and around into the annulus 24 through the openings 20 so that the exterior of the tubular 10 can be fully surrounded with cement up to and including a portion of the casing 12 . Before the cement sets, the piston/cylinder mechanism (not shown) is further actuated so that the swage assembly 16 moves further downwardly, as shown in FIG. 3. Segment 22 has now grown in FIG. 3 so that it encompasses the openings 20 . In essence, segment 22 which is now against the casing 12 also includes the openings 20 , thereby sealing them off. The seal can be accomplished by the mere physical expansion of segment 22 against the casing 12 . Alteratively, a ring seal 26 can be placed below the openings 20 so as to seal the cemented annulus 24 away from the openings 20 . Optionally, the ring seal 26 can be a rounded ring that circumscribes each of the openings 20 . Additionally, a secondary ring seal similar to 26 can be placed around the segment 22 above the openings 20 . As shown in FIG. 3, the assembly is now fully set against the casing 12 . The openings 20 are sealed and the tubular 10 is fully supported in the casing 12 by the extended segment 22 . Referring to FIG. 4, the swage assembly 16 , as well as the piston/cylinder assembly (not shown) and the spear which was used to support the tubular 10 , are removed with the running string 14 so that what remains is the tubular 10 fully cemented and supported in the casing 12 . The entire operation has been accomplished in a single trip. Further completion operations in the wellbore are now possible. Currently, this embodiment is preferred.
[0012] FIGS. 5 - 12 illustrate an alternative embodiment. Here again, the tubular 28 is supported in a like manner as shown in FIGS. 1 - 4 , except that the swage assembly 30 has a different configuration. The swage assembly 30 has a lower end 32 which is best seen in cross-section in FIG. 8. Lower end 32 has a square or rectangular shape which, when forced against the tubular 28 , leaves certain passages 34 between itself and the casing 36 . Now referring to FIG. 7, it can be seen that when the lower end 32 is brought inside the upper end 38 of the tubular 28 , the passages 34 allow communication to annulus 40 so that cementing can take place with the pumped cement going back up the annulus 40 through the passages 34 . Referring to FIG. 8, it can be seen that the tubular 28 has four locations 42 which are in contact with the casing 36 . This longitudinal surface location in contact with the casing 36 provides full support for the tubular 28 during the cementing step. Thus, while the locations 42 press against the inside wall of the casing 36 to support the tubular 28 , the cementing procedure can be undertaken in a known manner. At the conclusion of the cementing operation, an upper end 44 of the swage assembly 30 is brought down into the upper end 38 of the tubular 28 . The profile of the upper end 44 is seen in FIG. 10. It has four locations 46 which protrude outwardly. Each of the locations 46 encounters a mid-point 48 (see FIG. 8) of the upper end 38 of the tubular 28 . Thus, when the upper end 44 of the swage assembly 30 is brought down into the tubular 28 , it reconfigures the shape of the upper end 38 of the tubular 28 from the square pattern shown in FIG. 8 to the round pattern shown in FIG. 12. FIG. 11 shows the running assembly and the swage assembly 30 removed, and the well now ready for the balance of the completion operations. The operation has been accomplished in a single trip into the wellbore.
[0013] Accordingly, the principal difference in the embodiment shown in FIGS. 1 - 4 and that shown in FIGS. 5 - 12 is that the first embodiment employed holes or openings to facilitate the flow of cement, while the second embodiment provides passages for the cement with a two-step expansion of the upper end 38 of the tubular 28 . The first step creates the passages 34 using the lower end 32 of the swage assembly 30 . It also secures the tubular 28 to the casing 36 at locations 42 . After cementing, the upper end 44 of the swage assembly 30 basically finishes the expansion of the upper end 38 of the tubular 28 into a round shape shown in FIG. 12. At that point, the tubular 28 is fully supported in the casing 36 . Seals, as previously described, can optionally be placed between the tubular 28 and the casing 36 without departing from the spirit of the invention.
[0014] Another embodiment is illustrated in FIGS. 12 - 15 . This embodiment has similarities to the embodiment shown in FIGS. 1 - 4 . One difference is that there is now a sliding sleeve valve 48 which is shown in the open position exposing openings 50 . As shown in FIG. 12, a swage assembly 52 fully expands the upper end 54 of the tubular 56 against the casing 58 , just short of openings 50 . This is seen in FIG. 13. At this point, the tubular 56 is fully supported in the casing 58 . Since the openings 50 are exposed with the sliding sleeve valve 48 , cementing can now take place. At the conclusion of the cementing step, the sliding sleeve valve 48 is actuated in a known manner to close it off, as shown in FIG. 14. Optionally, seals can be used between tubular 56 and casing 58 . The running assembly, including the swage assembly 52 , is then removed from the tubular 56 and the casing 58 , as shown in FIG. 15. Again, the procedure is accomplished in a single trip. Completion operations can now continue in the wellbore.
[0015] FIGS. 16 - 19 illustrate another technique. The initial support of the tubular 60 to the casing 62 is accomplished by forcing a grapple member 64 down into an annular space 66 such that its teeth 68 ratchet down over teeth 70 , thus forcing teeth 72 , which are on the opposite side of the grappling member 64 from teeth 68 , to fully engage the inner wall 74 of the casing 62 . This position is shown in FIG. 17, where the teeth 68 and 70 have engaged, thus supporting the tubular 60 in the casing 62 by forcing the teeth 72 to dig into the inner wall 74 of the casing 62 . The grapple members 64 are elongated structures that are placed in a spaced relationship as shown in FIG. 17A. The spaces 76 are shown between the grapple members 64 . Thus, passages 76 provide the avenue for cement to come up around annulus 78 toward the upper end 80 of the tubular 60 . At the conclusion of the cementing, the swage assembly 82 is brought down into the upper end 80 of the tubular 60 to flare it outwardly into sealing contact with the inside wall 74 of the casing 62 , as shown in FIG. 18. Again, a seal can be used optionally between the upper end 80 and the casing 62 to seal in addition to the forcing of the upper end 80 against the inner wall 74 , shown in FIG. 18. The running assembly as well as the swage assembly 82 is shown fully removed in FIG. 19 and further downhole completion operations can be concluded. All the steps are accomplished in a single trip.
[0016] FIGS. 20 - 25 illustrate yet another alternative of the present invention.
[0017] In this situation, the swage assembly 84 has an upper end 86 and a lower end 88 . In the run-in position shown in FIG. 20, the upper end 86 is located below a flared out portion 90 of the tubular 92 . Located above the upper end 86 is a sleeve 94 which is preferably made of a softer material than the tubular 92 , such as aluminum, for example. The outside diameter of the flared out segment 90 is still less than the inside diameter 96 of the casing 98 . Ultimately, the flared out portion 90 is to be expanded, as shown in FIG. 21, into contact with the inside wall of the casing 98 . Since that distance representing that expansion cannot physically be accomplished by the upper end 96 because of its placement below the flared out portion 90 , the sleeve 94 is employed to transfer the radially expanding force to make initial contact with the inner wall of casing 98 . The upper end 86 of the swage assembly 84 has the shape shown in FIG. 22 so that several sections 100 of the tubular 92 will be forced against the casing 98 , leaving longitudinal gaps 102 for passage of cement. In the position shown in FIGS. 21 and 22, the passages 102 are in position and the sections 100 which have been forced against the casing 98 fully support the tubular 92 . At the conclusion of the cementing operation, the lower segment 88 comes into contact with sleeve 94 . The shape of lower end 88 is such so as to fully round out the flared out portion 90 by engaging mid-points 104 of the flared out portion 90 (see FIG. 22) such that the passages 102 are eliminated as the sleeve 94 and the flared out portion 90 are in tandem pressed in a manner to fully round them, leaving the flared out portion 90 rigidly against the inside wall of the casing 98 . This is shown in FIG. 23. FIG. 25 illustrates the removal of the swage assembly 84 and the tubular 92 fully engaged and cemented to the casing 98 so that further completion operations can take place. FIGS. 24 and 26 fully illustrate the flared out portion 90 pushed hard against the casing 98 . Again, in this embodiment as in all the others, auxiliary sealing devices can be used between the tubular 92 and the casing 98 and the process is done in a single trip.
[0018] Referring now to FIGS. 27 - 30 , yet another embodiment is illustrated. Again, the similarities in the running in procedure will not be repeated because they are identical to the previously described embodiments. In this situation, the tubular 106 is initially formed with a flared out section 108 . The diameter of the outer surface 110 is initially produced to be the finished diameter desired for support of the tubular 106 in a casing 112 (see FIG. 28) in which it is to be inserted. However, prior to the insertion into the casing 112 and as shown in FIG. 28, the flared out section 108 is corrugated to reduce its outside diameter so that it can run through the inside diameter of the casing 112 . The manner of corrugation or other diameter-reducing technique can be any one of a variety of different ways so long as the overall profile is such that it will pass through the casing 112 . Using a swage assembly of the type previously described, which is in a shape conforming to the corrugations illustrated in FIG. 28 but tapered to a somewhat larger dimension, the shape shown in FIG. 29 is attained. The shape in FIG. 29 is similar to that in FIG. 28 except that the overall dimensions have been increased to the point that there are locations 114 in contact with the casing 112 . These longitudinal contacts in several locations, as shown in FIG. 29, fully support the tubular 106 in the casing 112 and leave passages 116 for the flow of cement. The swage assembly can be akin to that used in FIGS. 5 - 11 in the sense that the corrugated shape now in contact with the casing 112 shown in FIGS. 29 at locations 114 can be made into a round shape at the conclusion of the cementing operation. Thus, a second portion of the swage assembly as previously described is used to contact the flared out portion 108 in the areas where it is still bent, defining passages 116 , to push those radially outwardly until a perfect full 360° contact is achieved between the flared out section 108 and the casing 112 , as shown in FIG. 30. This is all done in a single trip.
[0019] Those skilled in the art can readily appreciate that various embodiments have been disclosed which allow a tubular, such as 10 , to be suspended in a running assembly. The running assembly is of a known design and has the capability not only of supporting the tubular for run-in but also to actuate a swage assembly of the type shown, for example, in FIG. 1 as item 16 . What is common to all these techniques is that the tubular is first made to be supported by the casing due to a physical expansion technique. The cementing takes place next and the cementing passages are then closed off. Since it is important to allow passages for the flow of cement, the apparatus of the present invention, in its various embodiments, provides a technique which allows this to happen with the tubular supported while subsequently closing them off. The technique can work with a swage assembly which is moved downwardly into the top end of the tubular or in another embodiment, such as shown in FIGS. 20 - 26 , the swage assembly is moved upwardly, out of the top end of the tubular. The creation of passages for the cement, such as 34 in FIG. 8, 76 in FIG. 17A, or 102 in FIG. 22, can be accomplished in a variety of ways. The nature of the initial contact used to support the tubular in the casing can vary without departing from the spirit of the invention. Thus, although four locations are illustrated for the initial support contact in FIG. 8, a different number of such locations can be used without departing from the spirit of the invention. Different materials can be used to encase the liner up and into the casing from which it is suspended, including cement, blast furnace slag, or other materials, all without departing from the spirit of the invention. Known techniques are used for operating the sliding sleeve valve shown in FIGS. 12 - 15 , which selectively exposes the openings 50 . Other types of known valve assemblies are also within the spirit of the invention. Despite the variations, the technique winds up being a one-trip operation.
[0020] Those skilled in the art will now appreciate that what has been disclosed is a method which can completely replace known liner hangers and allows for sealing and suspension of tubulars in larger tubulars, with the flexibility of cementing or otherwise encasing the inserted tubular into the larger tubular.
[0021] The foregoing disclosure and description of the invention are illustrative and explanatory thereof, and various changes in the size, shape and materials, as well as in the details of the illustrated construction, may be made without departing from the spirit of the invention. | A method for securing and sealing one tubular to another downhole facilitates cementing prior to sealing and allows for suspension of one tubular in the other by virtue of pipe expansion techniques. | 4 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims priority to U.S. Provisional Application No. 61/835,871 filed Jun. 17, 2013.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] This invention was made with government support under Contract No. N00019-02-C-3003, awarded by the United States Navy. The Government has certain rights in this invention.
BACKGROUND
[0003] This disclosure is related to a hub for a gas turbine engine, particularly a one-piece cast or forged hub.
[0004] A gas turbine engine typically includes a fan section, a compressor section, a combustor section and a turbine section. Air entering the compressor section is compressed and delivered into the combustion section where it is mixed with fuel and ignited to generate a high-speed exhaust gas flow. The high-speed exhaust gas flow expands through the turbine section to drive the compressor and the fan section.
[0005] Gas turbine engines may include various hubs such as turbine exhaust cases, mid-turbine frames, transition or intermediate ducts, stator sections, or engine mounts. Hub assemblies may include inner and outer portions with airfoils or struts arranged in between the two portions. Current hubs are typically cast or forged in multiple pieces which then must be assembled, increasing cost and processing time.
[0006] Engine manufacturers continue to develop methods to ease engine manufacture and assembly, and improve engine efficiency.
SUMMARY
[0007] A unitary one-piece hub according to an exemplary embodiment of this disclosure, among other possible things includes first and second rings and a midsection arranged between the first and second rings. The midsection includes a plurality of windows configured to receive a plurality of cross members, and the windows each include a lip configured to surround the cross members.
[0008] In a further embodiment of the foregoing hub, at least one the first and second rings include a stiffening element.
[0009] In a further embodiment of any of the foregoing hubs, the stiffening element is located on one of a radially inner surface and a radially outward surface of the first ring.
[0010] In a further embodiment of any of the foregoing hubs, the stiffening element is a third ring.
[0011] In a further embodiment of any of the foregoing hubs, the plurality of cross members are airfoils.
[0012] In a further embodiment of any of the foregoing hubs, the plurality of cross members are struts.
[0013] In a further embodiment of any of the foregoing hubs, the plurality of cross members are welded to the lips.
[0014] In a further embodiment of any of the foregoing hubs, the lips are disposed on one of a radially inward side and a radially outward side of the midsection.
[0015] In a further embodiment of any of the foregoing hubs, the first and second rings and the midsection are cylindrical or conical in shape.
[0016] In a further embodiment of any of the foregoing hubs, the hub is formed by a casting process.
[0017] In a further embodiment of any of the foregoing hubs, the hub is formed by a forging process.
[0018] A gas turbine engine according to an exemplary embodiment of this disclosure, among other possible things includes a turbine, an exhaust arranged downstream from the turbine, and a case surrounding the turbine and exhaust. The case includes an inner case and an outer case wherein at least one of the inner and outer cases includes first and second rings and a midsection arranged between the first and second rings. The midsection includes a plurality of windows configured to receive a plurality of cross members, and the windows each include a lip configured to surround the cross members.
[0019] In a further embodiment of the foregoing gas turbine engine, the inner case includes the includes first and second rings and the midsection arranged between the first and second rings, the midsection including the plurality of windows configured to receive the plurality of cross members, and the windows each include a lip configured to surround the cross members.
[0020] In a further embodiment of any of the foregoing gas turbine engines, at least one of the first and second rings include a stiffening element.
[0021] In a further embodiment of any of the foregoing gas turbine engines, the plurality of cross members are airfoils.
[0022] In a further embodiment of any of the foregoing gas turbine engines, the plurality of cross members are welded to the lips.
[0023] A method of providing a hub for a gas turbine engine according to an exemplary embodiment of this disclosure, among other possible things includes the step of casting a first hub as one piece, the hub including first and second rings and a midsection arranged between the first and second rings. The midsection includes a plurality of windows configured to receive a plurality of cross members, and the windows each include a plurality of lips, respectively, configured to surround the cross members.
[0024] In a further embodiment of the foregoing method of providing a hub for a gas turbine engine, the method further includes the step of attaching the plurality of cross members to the plurality of lips.
[0025] In a further embodiment of any of the foregoing methods of providing a hub for a gas turbine engine, the attaching step comprises welding the plurality of cross members to the plurality of lips.
[0026] In a further embodiment of any of the foregoing methods of providing a hub for a gas turbine engine, the method further includes the steps of providing a second hub and installing the first hub into the second hub.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] The disclosure can be further understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein:
[0028] FIG. 1 schematically illustrates a gas turbine engine.
[0029] FIG. 2 schematically illustrates one-piece cast hub.
[0030] FIG. 3 schematically illustrates a cutaway view of the hub of FIG. 2 .
[0031] FIG. 4 schematically illustrates an alternate cutaway view of the hub of FIG. 2 .
[0032] FIG. 5 schematically illustrates a detail cutaway view of the hub of FIGS. 2-4 .
[0033] FIG. 6 schematically illustrates a hub assembly.
DETAILED DESCRIPTION
[0034] FIG. 1 schematically illustrates a gas turbine engine 20 . The gas turbine engine 20 is disclosed herein as a two-spool turbofan that generally incorporates a fan section 22 , a compressor section 24 , a combustor section 26 and a turbine section 28 . Alternative engines might include an augmenter section (not shown) among other systems or features. The fan section 22 drives air along a bypass flowpath B while the compressor section 24 drives air along a core flowpath C for compression and communication into the combustor section 26 then expansion through the turbine section 28 . Although depicted as a turbofan gas turbine engine in the disclosed non-limiting embodiment, it should be understood that the concepts described herein are not limited to use with turbofans as the teachings may be applied to other types of turbine engines including three-spool architectures.
[0035] The engine 20 generally includes a low speed spool 30 and a high speed spool 32 mounted for rotation about an engine central longitudinal axis A relative to an engine static structure 36 via several bearing systems 38 . It should be understood that various bearing systems 38 at various locations may alternatively or additionally be provided.
[0036] The low speed spool 30 generally includes an inner shaft 40 that interconnects a fan 42 , a low pressure compressor 44 and a low pressure turbine 46 . The inner shaft 40 is connected to the fan 42 through a geared architecture 48 (shown schematically) to drive the fan 42 at a lower speed than the low speed spool 30 . The high speed spool 32 includes an outer shaft 50 that interconnects a high pressure compressor 52 and high pressure turbine 54 . A combustor 56 is arranged between the high pressure compressor 52 and the high pressure turbine 54 . A mid-turbine frame 57 of the engine static structure 36 is arranged generally between the high pressure turbine 54 and the low pressure turbine 46 . The mid-turbine frame 57 further supports bearing systems 38 in the turbine section 28 . The inner shaft 40 and the outer shaft 50 are concentric and rotate via bearing systems 38 about the engine central longitudinal axis A which is collinear with their longitudinal axes.
[0037] Airflow through the core airflow path C is compressed by the low pressure compressor 44 then the high pressure compressor 52 , mixed and burned with fuel in the combustor 56 , then expanded over the high pressure turbine 54 and low pressure turbine 46 . The mid-turbine frame 57 includes airfoils 59 which are in the core airflow path. The turbines 46 , 54 rotationally drive the respective low speed spool 30 and high speed spool 32 in response to the previously mentioned expansion.
[0038] The engine 20 in one example is a high-bypass geared aircraft engine. In a further example, the engine 20 bypass ratio is greater than about six (6), with an example embodiment being greater than ten (10), the geared architecture 48 is an epicyclic gear train, such as a planetary gear system or other gear system, with a gear reduction ratio of greater than about 2.3 and the low pressure turbine 46 has a pressure ratio that is greater than about 5. In one disclosed embodiment, the engine 20 bypass ratio is greater than about ten (10:1), the fan diameter is significantly larger than that of the low pressure compressor 44 , and the low pressure turbine 46 has a pressure ratio that is greater than about 5:1. Low pressure turbine 46 pressure ratio is pressure measured prior to inlet of low pressure turbine 46 as related to the pressure at the outlet of the low pressure turbine 46 prior to an exhaust nozzle. The geared architecture 48 may be an epicycle gear train, such as a planetary gear system or other gear system, with a gear reduction ratio of greater than about 2.5:1. It should be understood, however, that the above parameters are only exemplary of one embodiment of a geared architecture engine and that the present invention is applicable to other gas turbine engines including direct drive turbofans.
[0039] A significant amount of thrust is provided by the airflow through the bypass flow path B due to the high bypass ratio. The fan section 22 of the engine 20 is designed for a particular flight condition—typically cruise at about 0.8 Mach and about 35,000 feet. The flight condition of 0.8 Mach and 35,000 ft, with the engine at its best fuel consumption—also known as bucket cruise Thrust Specific Fuel Consumption (“TSFC”). TSFC is the industry standard parameter of lbm of fuel being burned divided by lbf of thrust the engine produces at that minimum point. “Low fan pressure ratio” is the pressure ratio across the fan blade alone, without a Fan Exit Guide Vane (“FEGV”) system. The low fan pressure ratio as disclosed herein according to one non-limiting embodiment is less than about 1.45. “Low corrected fan tip speed” is the actual fan tip speed in ft/sec divided by an industry standard temperature correction of [(Tambient deg R)/518.7]̂0.5. The “Low corrected fan tip speed” as disclosed herein according to one non-limiting embodiment is less than about 1150 ft/second.
[0040] Referring to FIG. 2 , an example hub 70 is schematically shown. The example hub 70 may be axially aligned on an engine axis A. The hub 70 in this example is an inner hub for a turbine 46 , 54 , however, in another example the hub 70 may be an outer hub for a turbine 46 , 54 , a mid-turbine frame 57 , a transition or intermediate duct 71 within the engine 20 , a stator section for the compressor 44 , 52 or turbine 46 , 54 , or an engine 20 mount. In another example, the hub 70 may be incorporated into any static component in the engine 20 .
[0041] The hub 70 is a one-piece cast or forged structure. The hub 70 includes a forward ring 72 (a first ring), a midsection 74 , and an aft ring 76 (a second ring). The forward ring 72 may be cylindrical or conical in shape. One of the radially inner and the radially outer surfaces 78 , 80 of the forward ring 72 provides a flowpath for upstream air entering the hub 70 . The other of the radially inner and outer surfaces 78 , 80 of the forward ring 72 may include structural supports or stiffening elements. In another example, the forward ring 72 may be cantilevered off of the hub 70 .
[0042] The aft ring 76 is similar to the forward ring 72 . One of the radially inner and outer surfaces 84 , 86 of the aft ring 76 may include stiffening elements. For example, the stiffening element may be a cast or forged ring 87 on the radially inner side 86 of the aft ring 76 . The aft ring 76 may also be cantilevered off of the hub 70 . The other of the radially inner and outer surfaces 84 , 86 may provide a flowpath for downstream air exiting the hub 70 . The aft ring 76 may include one or more flanges 82 for connecting to other parts of the engine 20 . The aft ring 76 may also include flanges (not shown) and openings 89 . The midsection 74 includes windows 88 to accommodate cross members 106 .
[0043] Referring to FIGS. 3-4 , a schematic cutaway view along the line 3 - 3 ( FIG. 2 ) of the hub 70 is shown. In the example shown in FIG. 3 , the windows 88 are configured to receive cross members 106 such as airfoils (not shown). In the example shown in FIG. 4 , the windows are configured to receive cross members 106 such as struts (not shown).
[0044] As is shown in FIG. 5 , the windows 88 may include a lip 90 extending radially inward from the window 88 . The lip 90 allows for attachment of the cross members 106 to the hub 70 by conventional fastening or bonding means. In one example, the cross members 106 may be welded to the lip 90 . In another example, the lip 90 may extend radially outward from the hub 70 .
[0045] FIG. 6 shows a hub assembly 100 . The hub assembly 100 may include an outer member 102 and an inner member 104 with the cross members 106 arranged therebetween. One of the inner and outer members 102 , 104 may be a hub 70 as described above. That is, if the hub 70 is the inner member 102 , the cross members 106 extend radially outward from the hub 70 . If the hub 70 is the outer member 104 , the cross member 106 extend radially inward from the hub 70 .
[0046] Accordingly, casting or forging the hub 70 as one piece may provide a hub 70 with enhanced properties, such as improved directional uniformity. Additionally, the potential to employ a near-net casting process allows for limited machining after casting as one piece. A one-piece casting process may provide significant cost saving by eliminating the need for many complex fabrications and assemblies.
[0047] Although an example embodiment has been disclosed, a worker of ordinary skill in this art would recognize that certain modifications would come within the scope of this disclosure. For that reason, the following claims should be studied to determine the scope and content of this disclosure. | A unitary one-piece hub has first and second rings and a midsection arranged between the first and second rings. The midsection includes a plurality of windows configured to receive a plurality of cross members. The windows include a lip configured to surround the cross members. A gas turbine engine and a method of providing a hub for a gas turbine engine are also disclosed. | 5 |
PRIORITY INFORMATION
[0001] This application claims the benefit of U.S. Provisional Application No. 60/384,604 filed on Aug. 26, 2002.
BACKGROUND AND SUMMARY
[0002] The Internet is a loosely coupled network of distributed computing systems. The network interface permits most any person to connect to the Internet, and to communicate with most any other person in the Internet. The connections require only common telephone cabling, and as such most any person from any continent or legal jurisdiction may connect to the Internet.
[0003] Various protocols exist for communication via the Internet, such as e-mail messages and web pages. E-mail messages are may be generated automatically by mechanized electronic machines such as computers, and so are a popular way of distributing messages.
[0004] However, in many cases, the sender of an e-mail message has only a casual or no relationship to the recipient of the e-mail message. As such, often times the sender of an e-mail message will send undesirable or even offensive or illegal material to the recipient of an e-mail message. Such undesirable or even offensive material may take the form of pornographic or other adult material or nudity. In many government jurisdictions, certain types of pornographic material are banned, while in other jurisdictions, they are permitted. Also, some recipients of e-mail messages may prefer to receive pornographic materiel, while others may not. As a user of the Internet, there is no way to determine if an incoming e-mail message is pornographic or not unless opening the message. But opening the message in itself may result in display of offensive material, and so the problem remains. The sender of a pornographic e-mail may not be breaking any laws locally, but the e-mail may contain material which is objectionable or even illegal for the recipient in another jurisdiction to posses. Further, pornographic pictures are also easily posted and sent through the Internet.
[0005] One method of dealing with this problem is by using spam blockers and filters. Such filters attempt to remove objectionable material in e-mails while the e-mail is in transit and before the e-mail reaches the user's computer. Such filters however are only partially effective in detecting and eliminating offensive e-mails, partly because the sender of the e-mail may change the format slightly so that blocking software no longer recognizes and blocks the e-mail. Thus there is a lot of time and money spent and wasted in trying to block undesired and/or pornographic e-mails and web pages. Thus it is desirable to more effectively prevent e-mails and Internet data with undesirable or offensive material.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] [0006]FIG. 1 is an Internet address according to the prior art.
[0007] [0007]FIG. 2 is Internet address according to an embodiment of the invention.
[0008] [0008]FIG. 3 is a diagram showing Internet address processing events according to an embodiment of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0009] [0009]FIG. 1 shows a conventional Internet address. The specific domain name is “school”, and identifies the holder of the address with a name. The top level domain suffix is “le”, which may indicate that the name is used by a government entity.
[0010] More generally, a conventional Internet address typically contains a specific domain name indicating the holder of the specific domain, and one or more suffixes indicating classifications of the domain
[0011] [0011]FIG. 2 shows Internet addresses according to an embodiment of the invention. The unique name “school” is still in the address. The .gov suffix is still present. Added to the address is an additional portion. The additional portion contains an identifier “.18”. In 201 the .18 identifier is placed in the url (uniform resource locator) of an Internet address. 202 is an e-mail address which makes use of a domain with a .18 indicator.
[0012] The .18 indicator is promoted as being a novel indicator of protected legal status of a minor. When a .18 indicator is found as a portion of a web or e-mail address, the sender of an e-mail is put on notice ahead of time that the recipient is in a protected group.
[0013] In another embodiment, the .18 (pronounced “dot eighteen”) extension may be used as a prefix, suffix or add-on to a regular traditional e-mail address or domain name. For example, a user may have the e-mail address sue@hotmail.com and also use or have an e-mail address sue@hotmail.com.18. The .18 extension is publicly promoted as being reserved for minors and others who do not wish to receive pornographic material. The .18 suffix may be a specially designated nomenclature that enjoys government protected status. Any party may be free to use the .18 extension with their own Internet address. When a person uses the .18 extension as part of their e-mail or web address, it signals anyone that wishes to send an e-mail or a web page with adult content to that address that the holder of that address is or may be a minor, and does not wish to receive such material.
[0014] The .18 extension may be legislated by various government authorities in different jurisdictions such that any person or entity sending certain definable material to any e-mail address that contains a .18 extension is a guilty of a punishable act.
[0015] In an embodiment, the Internet backbone and domain name servers may be configured to recognize the specially designated .18 extension, and pass the e-mail through to the base address. Thus in this embodiment, there is no daily administration required to maintain the system, and any person is free to use the .18 extension any time they wish to do so.
[0016] In a preferred embodiment, shown in FIG. 3, an Internet service provider (ISP) is registered to use a .18 or “minor” extension. In this case, the domain name of the service provider includes the “minor.” name. For example, the name “ISP.com” becomes “minor.ISP.com” or “school.gov” becomes “minor.school.gov” or “school.gov.18”. Adding the “minor.” prefix in front of the domain name is an example of a novel use of a third level domain name. Such third level domain addressing schemes are already provided for in the Internet system. The Internet routes the message as if the “minor.” prefix were not even present. Only when the message arrives at the recipient's ISP is the minor. prefix recognized and acted upon. Thus in one embodiment the system may be implemented with no change in current Internet standards.
[0017] The “minor.” enabled ISP may provide additional novel actions that further protect any person with a “minor.” name. The “minor.” enabled Internet service provider may operate computing equipment 303 that performs additional processing functions on a portion or all e-mail or web traffic that flows from an Internet data sender 301 through the Internet 302 to the ISP with content authorization processor 303 to an Internet data recipient 305 . Internet data recipient 305 uses a “minor.” or .18 type designation. These additional processing functions may perform the function of content authorization processing. The content authorization processor 303 checks the web or Internet protocol (IP) address of the sender of any e-mail or web pages that pass through its servers. For example, if unknown Internet data sender bill@spam.com 301 with IP address 216.115.224.88, an Internet user, sends an e-mail addressed to st@minor.ISP.com. The ISP.com content authorization server 303 server checks a database 304 to see if bill@spam.com or IP address 216.115.224.88 has ever sent any e-mail or web pages to ISP.18.com before. If the message sender from IP 216.15.224.88 has never sent an message to ISP.18.com before, the ISP.18.com will then first send a warning notice 306 back to unknown Internet data sender with IP address 216.115.224.88 advising Internet user 216.115.224.88 that minor.ISP.com is a protected server and/or gateway, that the addressee is a minor or does not wish to receive such certain types of material, these certain types of material are not permitted, sending certain material to the server may be illegal, and the sender may be prosecuted. Such a message may be as shown below:
[0018] “Warning—The recipient specified in your e-mail is a minor under the age of 18 years old or has requested no pornographic material be sent to them. If your e-mail or web data contains pornographic material, you may be violating applicable laws. Do you wish to proceed?” (yes/no) “By checking yes you certify that this e-mail or web transmission contains no such objectionable material.”
[0019] The notice 306 may be in the form of an e-mail, a web page, or other Internet format. The .18 enabled ISP need only add a small amount of software to fully implement the system.
[0020] Internet data sender 301 will receive the warning message 306 and then be required to acknowledge that it received the notice and that Internet data sender 301 agrees to the terms of the .18 service. He does this preferably by manually entering a yes response on the keyboard. The yes acceptance response is then sent back to the content authorization processor 303 , and is noted and/or recorded in the database 304 . After receiving a yes response to the warning the ISP.18.com server will then pass the message or web page from the Internet data sender 301 to the Internet data recipient 305 (st@minor.ISP.com for example). Once the Internet data sender 301 has agreed to the terms of use of ISP.18.com, ISP.18.com may pass further messages from the Internet data sender 301 without further warning messages, or further warning messages may be occasionally sent to insure continuing compliance. The content authorization processor 303 may temporarily hold the message or data from data sender 301 while the content authorization processor 303 awaits a positive response 307 from Internet data sender 301 to the warning notice 306 . If the Internet data sender does not agree or certify the material to not contain nudity or adult content, the e-mail or other web content from data sender 301 is deleted and not forwarded to data recipient 305 .
[0021] In an alternative embodiment, the content authorization processor 303 is bi-directional. That is, after sender of Internet data 301 successfully sends a message 302 to Internet data recipient 305 , Internet data recipient 305 then replies to the message, thereby becoming an Internet data sender. The content authorization processor 303 processes the reply is a similar manner as to the Internet message 302 .
[0022] The domain name system (DNS) is a system using a database to link the numeric Internet protocol (IP) address of an Internet user with a text based name. Thus for example, Internet address 206.115.224.58 may be linked to business.com. The numeric (IP) portion of the name makes the system easier for computers to identify the user, and the text name portion makes it easier for humans to identify the user. A known computer called a domain name server allows someone with either just the text portion or just the numeric portion of a web or other IP address to look up and find the other corresponding portion. Thus when a sender of Internet traffic is identified only by their IP address, the content authorization processor 303 may do a lookup in the DNS server database, and determine the corresponding text value of the identity of the sender of an Internet message. The content authorization processor 303 then checks the text value for the .18 indicator, and makes a determination about forwarding the message. In one embodiment, a certain block of IP numbers, such as for example addresses ranging 206.115.221.1 to 206.115.221.255 are set aside and designated for reserved use just with .18 text names. Any IP address in this range automatically is associated with the .18 indicator, and the text portion of any Internet address within one of the designated ranges of IP numbers will automatically have the .18 designator in the text portion. Then, when content authorization processor 303 receives an Internet message 302 from any sender 301 destined for a recipient 305 within .18 designated IP ranges, the content authorization processor automatically handles the message as a .18 message, and no lookup to the domain name server is required.
[0023] Further information may be made available to recipients of the warning message 306 , such as statues and/or definitions, to help them make the correct yes/no choice. The ISP may also operate a reporting service where users of the system may report violations of the agreement. Thus no person will accidentally send pornographic material to a person who does not wish to receive it. Further, a record is able to be maintained in database 304 whereby evidence may be made available for example to law enforcement authorities. The ISP is generally a third party, unrelated to either Internet user.
[0024] The system may be used along with known country code designators. For example, child23@minor.school.gov.us is an e-mail address for a minor in the Unites States territory.
[0025] Furthermore, operators of pornographic web sites may either voluntarily or by mandate configure their web servers so that they will automatically reject any inquiry or request from any person or computer address with a .18 code in their e-mail address or domain name. In this example, parents and other guardians may set up “.18” accounts for the minors, and the accounts are protected, for example by password, against bypassing by the minor. If the minor should send a request such as an e-mail or inquiry to a web site with pornographic materials, the web site will see the .18 designation in the url of the minor, and refuse to send the requested materials. Thus the system described herein provides a way for the sender of an e-mail or operator of a web site to know ahead of time that the requestor does not wish to receive material such as is being sent, before it is even sent, and that the sending of such material may even in fact be illegal. This then reduces the amount network clutter, and provides much easier administration for the e-mail user and more protected use by minors. The sender may cancel the transmission, or send a warning notice to the requester that the requester is not permitted access to that material.
[0026] In another embodiment, the content authorization processor 303 and the database 304 are located on the Internet data recipient computer 305 .
[0027] In another embodiment, the warning message is a part of the Internet data sender software.
[0028] Businesses may also use the content authorization processor 303 to reduce undesired Internet traffic such as bulk, automated e-mails, and other network traffic. Bulk automated e-mail, often called spam, are generated by automatic addressing schemes, where multiple repeating messages are sent consecutively to different recipients in a fully automatic machine generated manner without human intervention or human generated individual addressing. The process is the same as when used by a minor to prevent pornographic material. Any time an Internet user sends traffic to an Internet recipient protected with the content authorization processor, the sender is sent a warning message with terms of use. The Internet data sender must then accept the terms of use before the Internet traffic is permitted to pass through. A record of the acceptance of the terms of use is then kept on file in a database accessible by the authorization processor, and checked each time new Internet traffic is sent.
[0029] The warning message preferably requires a manual yes/no type input on the keyboard or mouse of the sending computer, thus requiring human intervention before passing the message through. Alternative techniques may be used to help insure a manual yes/no input is provided in response to the warning message, thus reducing the chance for abuse by bulk e-mails senders. These techniques for instance require the user to manually type in a number in a picture before accepting the warning message reply. The particular techniques used are design choices for those skilled in the art.
[0030] Thus by perceiving a specific domain name, such as .18, in the domain name of an Internet data recipient, in advance, the sender of a pornographic e-mail or other material is put on prior notice that transmission of such pornographic material is illegal to send to the domain.
[0031] When a user signs up for an Internet account, they may either sign up for a conventional Internet account, or they may sign up for a .18 account. Both accounts are similar, except the .18 account has the .18 identifier tag in the name. Once a user signs up for a .18 account, all e-mail addresses and all web pages and other web traffic from and for that user automatically includes the .18 designation. The user of the account is thus protected against undesired material.
[0032] When a sender of spam material obtains a list of e-mail address to which to address their spam, there will be many names on the list. Some of the e-mail address may contain the .18 designator in the e-mail address. Software of the spam sender then sorts through the list of e-mail addresses, and if any pornographic material is being sent in the current spam, then addresses with the .18 designation are removed from the list by the software, such that the sending of the spam is blocked. Once the software is configured using known techniques to recognize the .18 designation, minimal or no further human intervention is required by the e-mail sender to prevent improper sending of undesired e-mails. Specifically, filter lists, blocking software, manual monitoring and other updates are not required.
[0033] The sender then has the option to cancel the message if the message is not appropriate. This may be done with a yes/no check box or other input means. Further, a copy of the authorization to send (the yes box checked by the sender) may be sent along with the e-mail.
[0034] The .18 designator in the url or e-mail address may be parsed and routed according to known techniques, allowing the message to be delivered as intended.
[0035] While an exemplary embodiment is described, numerous various substitutions and changes may be made, and still fall within the spirit and scope of the invention. For example, the .18 indicator is chosen by way of example only, and not limitation. Numerous other indicators, for example minor and child may also be used.
[0036] For additional example, other types of material other than pornographic material may be restricted to .18 addresses, such as cigarette advertising.
[0037] Additionally, with the domain name system used by the Internet, each domain name has a corresponding number associated with it. For example, business.com may have an IP address of 216.115.224.77. For example, sue@ISP.com is a text name, but the domain name system (DNS) also provides a numeric number for the name, for computer use. For example sue@ISP.com may be the domain name for Internet protocol (IP) number 206.115.224.3, or any such similar number. While the .18 designator is used with the text version of the name, a designator may likewise or alternately be used with the numeric version of the name. For example 216.115.224.77.18 or 206.115.224.3.18 Alternately, a specific group of numbers may be set aside and assigned to be used as .18 or “minor” numbers. For example, the range of numbers of 216.115.224.1-216.115.224.255 may be designated as reserved for use by minors. In this case, anyone sending a pornographic e-mail to any of the designated addresses would be in violation of the standards. In this case, the domain name system (DNS) may automatically append the .18 or minor name to any number within the designated range. The sender of an Internet message, having only either the IP address or the domain name, can determine the associated corresponding IP address or domain name by doing a lookup on a domain name server or other database.
[0038] Because the .18 designator is in the address of the recipient of the e-mail or web page, the sender is able to know ahead of time that the recipient is a minor, and may be more subject to and prosecutable for various local pornography laws than would otherwise be the case. Further, specific legal content standards may be developed for use in .18 name extensions. Thus the system provides a viable and effective of reducing or eliminating undesirable Internet content, and provides for a safer computing environment for minors.
[0039] The system may be used equally effectively on e-mails, web pages, or other Internet traffic, and is meant for all types of Internet traffic using both current and future communication protocols. | A system for reducing or eliminating objectionable e-mails and other Internet content, including pornography. The system helps prevent undesired pornographic solicitations, thus helping free the personal computer user from the task of sorting and disposing of undesirable content. The system also provides increased protection against undesired pornographic Internet content for minors, and reduces unneeded Internet traffic. The system may include a content authorization processing device, a database, and an Internet data sender agreement. The system employs a unique domain name addressing system whereby senders of objectionable material may be put on notice prior to sending such material. | 7 |
CLAIM OF PRIORITY
[0001] This application claims priority from ENHANCED PORTALS [FLAGSTAFF RELEASE], U.S. Provisional Application No. 60/386,487, Inventors: Phil Griffin, et al., filed on Oct. 24, 2001, and which is incorporated herein by reference.
CROSS REFERENCE TO RELATED APPLICATIONS
[0002] This application is related to the following co-pending applications which are each hereby incorporated by reference in their entirety: SYSTEM AND METHOD FOR DELEGATED SYSTEM ADMINISTRATION, U.S. Application Ser. No. ______, Inventors: Phil Griffin, et al., filed on ______; SYSTEM AND METHOD FOR RULE-BASED ENTITLEMENTS, U.S. Application Ser. No. ______, Inventors: Phil Griffin, et al., filed on ______; and SYSTEM AND METHOD FOR PORTAL PAGE LAYOUT, U.S. Application Ser. No. ______, Inventors: John Haut, et al., filed on ______.
FIELD OF THE DISCLOSURE
[0003] The present invention disclosure relates to interactive tools for portal management.
BACKGROUND
[0004] A portal is a point of access to data and applications that provides a unified and personalized view of information and resources. Portals are typically implemented as websites on the World Wide Web and are accessible via web browser applications. Portals have evolved from simple one page content sites to multi-page aggregations of content and applications with integration to back-office systems. Portal complexity has also increased due to the growth in the number of portal users. However, tools for administering portals have not kept pace with these trends.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] [0005]FIG. 1 is an illustration of an exemplary portal administration graphical user interface (GUI) in one embodiment of the invention.
[0006] [0006]FIG. 2 is an illustration of an exemplary group hierarchy GUI in one embodiment of the invention.
[0007] [0007]FIG. 3 is an illustration of an exemplary portal management GUI in one embodiment of the invention.
[0008] [0008]FIG. 4 is an illustration of an exemplary delegated administration GUI in one embodiment of the invention.
[0009] [0009]FIG. 5 is an illustration of an exemplary group portal home GUI in one embodiment of the invention.
[0010] [0010]FIG. 6 is an illustration of an exemplary user management GUI in one embodiment of the invention.
[0011] [0011]FIG. 7 is an illustration of an exemplary portal page selection GUI in one embodiment of the invention.
[0012] [0012]FIG. 8 is an illustration of an exemplary page attribute GUI in one embodiment of the invention.
[0013] [0013]FIG. 9 is an illustration of an exemplary page entitlements GUI in one embodiment of the invention.
[0014] [0014]FIG. 10 is an illustration of an exemplary portlet attributes GUI in one embodiment of the invention.
[0015] [0015]FIG. 11 is an illustration of an exemplary portlet entitlements GUI in one embodiment of the invention.
DETAILED DESCRIPTION
[0016] The invention is illustrated by way of example and not by way of limitation in the figures of the accompanying drawings in which like references indicate similar elements. It should be noted that references to “an” or “one” embodiment in this disclosure are not necessarily to the same embodiment, and such references mean at least one.
[0017] In one embodiment of the invention, resources for portal applications deployed on a web server (hereinafter referred to as a “server”) are managed with a portal administration tool (hereinafter referred to as a “tool”). Servers are available from a variety of venders, such as the BEA WebLogic Server™ offered by BEA Systems, Inc. of San Jose, Calif. Aspects of one embodiment are realized in the BEA WebLogic Portal Administration Tools, available from BEA Systems, Inc. In one embodiment, by way of example, a tool can be implemented as one or more Java Server Pages™ (JSP's). JSP's are part of the Java™ programming environment which is available from Sun Microsystems, Inc. of Santa Clara, Calif. JSP technology separates presentation of a GUI from application logic so that one can be changed independent of the other.
[0018] Portal applications deployed on a server can present a GUI which, in one embodiment, can be rendered by a web browser, such as the Microsoft Internet Explorer, available from Microsoft Corp. of Redmond, Wash. By way of a non-limiting example, a portal application could present to a user a list of real-time stock quotes. A portal application could also work behind-the-scenes, providing data and services in support of the portal. A portal and its applications can be developed using commercially available development tools such as BEA WebLogic Portal™, available from BEA Systems, Inc.
[0019] [0019]FIG. 1 is an illustration of an exemplary portal administration GUI in one embodiment. The GUI enables an individual to create or register a number of portal users, each having the same or different administration capabilities. By assigning a portal user to a role-based administrator group, the portal user can acquire the administrative authority that is assigned to that group. In one embodiment, the following types of portal users can be created:
User Type Description Users Users are individuals that exist in the system with user names and passwords. Only System Administrators can create users. Users are not part of a particular group. System SA's are the superusers and can manage any aspect of Administrators any portal. They can only be created by other SA's. (SA's) AdminEligible AdminEligible group members are eligible for Users administrative abilities. Users can be added to the AdminEligible group by SA's. Portal PA's are AdminEligible users that have been assigned Administrators administrative authority for a particular portal (PA's) application. PA's can be created by SA's and other PA's. Group GA's are AdminEligible users who are given limited Administrators administrative authority for specific group portals. A (GA's) group portal is a portal that is associated with a user group. A user group can be any arbitrary collection of users that is determined statically, or dynamically by evaluating rules that take into account information about a user and other information. GA's can be created by SA's, PA's, and other GA's.
[0020] In one embodiment, a portal user can be a registered user or an anonymous visitor. In order to assign a user administrative abilities of any kind however, they must be registered. Registering a portal user provides them with a user name and a password, and enables them to be selected for addition to role-based user groups. In one embodiment, by way of illustration, the following procedure can be used to register a portal user:
[0021] 1. Select User Management icon 100 as illustrated in FIG. 1. A User Management home page then appears (not shown). By way of a non-limiting example, selection or interaction with the tool can be accomplished using an input device such as a mouse, trackball, or similar device, a keyboard, a gesture recognition system, a speech recognition system, etc.
[0022] 2. Select a Create icon in the Users bar (not shown). The Create New Users page then appears.
[0023] 3. In a Create New User page (not shown), enter the user Name, Password, and User Type.
[0024] In one embodiment, a registered user can be associated with a property set. A property set is a convenient way to give a name to a group of properties for a specific purpose. Generally speaking, a property can be considered a name/value pair. Property sets serve as namespaces for properties so that properties can be conveniently grouped and multiple properties with the same name can be defined. Properties can include the following information:
Name Value Property The name of the property, such as Gender. name Data type Specifies the data type of the property value. For example, possible data types are Text, Numeric, Floating-Point number (equivalent to Double in Java), Boolean, and Date/Time. Selection Specifies whether a property is single-valued (has a single mode default value) or multi-valued (has a collection of default values). Value range Specifies whether the defaults are restricted to one specific value, one or more specific values, or any value. Description A textual description of the property, perhaps describing the purpose of the property. Values A list of values from which the user will pick, and you can designate which of the values is the default.
[0025] By way of a non limiting example, a property set called Demographics can describe portal user properties such as Age, Gender, Income, and so forth. Because property sets create unique namespaces for properties, another property set can also have a property called Gender, and the two values will be kept separate. Property sets and other user attributes can be edited using a GUI.
[0026] By way of a non limiting example, a registered user can have property set named Customer Properties which defines properties for an e-commerce customer, for example, such as First Name, Last Name, Home Phone, Email, and Customer Type. In one embodiment, the following procedure can be used to assign property sets to the new user:
[0027] 1. In a Create New Users page (not shown), Select the name of the new user. A user management page for your new user appears (not shown).
[0028] 2. Use a drop-down menu to select a property set for the user (not shown).
[0029] A portal user can be promoted to an SA by adding them to the System Administrator group. In one embodiment, in order to assign a portal user to the System Administrator Group, they must have already been registered as an SA. In one embodiment, the following procedure can be followed:
[0030] 1. Select the User Management icon 100 in the Administration Tools Home page (FIG. 1). A User Management page appears.
[0031] 2. Select a Groups icon in the User Management page (not shown). The Group Hierarchy page appears (FIG. 2).
[0032] 3. In the Group Hierarchy page, Select “SystemAdministrator” 200 .
[0033] 4. An Edit Groups page (not shown) displays information for the SystemAdministrator group and allows a registered portal user to be added to the group.
[0034] In one embodiment, before a user can be given PA or GA authority, they must first be added to the AdminEligible group. AdminEligible members are registered users that are added to the AdminEligible group by an SA. In another embodiment, registered users can be added to the AdminEligible group by a PA or a GA. In one embodiment, the following procedure can be followed to add an SA:
[0035] 1. Select the User Management icon 100 in the home page (FIG. 1). A User Management page appears (not shown).
[0036] 2. Select a Groups icon in the User Management page. The Group Hierarchy page appears (FIG. 2).
[0037] 3. In the Group Hierarchy page, Select the AdminEligible link 210 .
[0038] 4. Select an add/remove icon (+/−) in an AdminEligible page (not shown).
[0039] 5. Search a for user to add to the AdminEligible group (not shown).
[0040] 6. Highlight the desired user and Select a right arrow to add them to the Group Search Results list (not shown).
[0041] [0041]FIG. 4 is an illustration of an exemplary delegated administration GUI in one embodiment. In one embodiment, PA's have authority to manage aspects of their associated portal. A PA is created by adding a member of the AdminEligible group to the Portal Administrator group and specifying their privileges. SA's and PA's can create a new PA from an existing AdminEligible user. A PA may have authority in multiple portals. In one embodiment, the following procedure can be used to create a new PA:
[0042] 1. Select the Portal Management icon 102 in the home page (FIG. 1). The Portal Management home page appears (FIG. 3), listing all group portals within the portal application. Group portals provide a means for organizing users with common characteristics into a single category. Portal groups also allow for the definition of different views of a portal for different user groups, making it seem as if users in each group are looking at completely different web sites.
[0043] 2. Select the Edit Portal Administrators link 300 . An Edit Portal Administrators page appears (not shown).
[0044] 3. In the Edit Portal Administrator page, Select Create New Administrator. An Add New Portal Administrator page appears (not shown).
[0045] 4. Select a user to add to the Portal Administrator group (not shown). Any user in the AdminEligible group or existing GA is eligible.
[0046] 5. The Delegate Administration page appears (FIG. 4).
[0047] [0047]FIG. 4 is an illustration of an exemplary delegated administration GUI in one embodiment. Checking each box allows the new PA to perform that function on any group portal within the associated portal application. In the User Management row 400 , if “Grant” is checked, the PA can create, add, remove, delete, and edit properties of users. In one embodiment, delegated system administration involves the conveying of a capability (e.g., the ability to perform a system administration task) from one user to another. If “Can Delegate” is checked, the PA can choose to assign or remove the user management authority of other PA's or GA's associated with this portal application.
[0048] In Portal Page Management row 402 , if “Grant” is selected, the PA can perform portal page administration. In one embodiment, portal page administration entails controlling behavioral aspects that a visitor experiences when accessing a portal, such as whether a portlet is viewed as a popup window or a smaller window within the page of origin. A portlet is an application that manages its own GUI. In one embodiment, a portlet is implemented as a JSP. If “Can Delegate” is checked, the PA can choose to give or remove portal page management authority of other PA's or GA's associated with this portal application. If “Can Set Entitlements” is selected, the PA can control visitor portal page capabilities by associating entitlement segments with portal pages. In one embodiment, an entitlement segment is a dynamic visitor group based on common characteristics that allows a member of the group to view certain aspects of a portal. For example, if a portal provides information about upcoming city council elections in Los Angeles, an entitlement group for that portlet could consists of visitors who live in Los Angeles county and are of voting age. Meeting an entitlement segment's criteria may also give the user certain privileges in a portal. In the above example, any visitor that lives in Los Angeles county and is of voting age might be given the ability to edit the presentation or color scheme of their portal.
[0049] Portlet Management row 404 controls a PA's authority of the management of portlets. In one embodiment, if an administrator has the capability of managing portlets, the administrator can define and modify the resources that are available to a portlet. The administrator can also set portlet defaults, such as whether the portlet will be available to users, whether the portlet can be minimized, whether the portlet can be maximized, etc. If “Grant” is selected, a PA can perform portlet administration. If “Can Delegate” is selected, a PA can choose to give or remove portal management authority of other PA's or GA's associated with this portal application. If “Can Set Entitlements” is selected, a PA can control visitor group capabilities by associating entitlement segments with portlets.
[0050] In one embodiment, a skin can be a collection of files that includes a cascading style sheet and a directory of images that define the look and feel of a portal. Every button, banner, portlet header, background color, and font characteristic can be determined by the skin. Skins management entails selecting the default skin for a group portal and determining what skins are available to users for customization of their view of a portal. In the Skins Management row 406 , if “Grant” is selected, a PA can perform skins management. If “Can Delegate” is checked, a PA can choose to give or remove skins management authority of other PA's or GA's associated with this portal application.
[0051] [0051]FIG. 5 is an illustration of an exemplary group portal home GUI in one embodiment. In one embodiment, GA's are users in the AdminEligible group who are given limited administrative authority for specific group portals. For a user to be a GA, they must first be placed in the AdminEligible group by an SA. In one embodiment, the following procedure can be used to create a GA:
[0052] 1. Select the Portal Management icon 102 in the Portal Administrator Home page (FIG. 1). The Portal Management Home page appears (FIG. 3).
[0053] 2. Select the group portal for which you wish to add a GA. The Group Portal Management Home page appears (FIG. 5).
[0054] 3. Select “Edit Delegated Administration Settings for Group Administrators” 500 . An Edit Group Administrators page appears (not shown).
[0055] 4. Select Create New Administrator. A Choose Administrator page appears (not shown).
[0056] 5. Select a user to add to the Group Administrator group (not shown).
[0057] 6. The Delegate Administration page appears (FIG. 4).
[0058] 7. In the Delegate Administration page, determine what authority the GA will have. Checking each button allows the new GA to perform that function for this group portal only. In one embodiment, these functions are a subset of the functions available to PA's.
[0059] [0059]FIG. 6 is an illustration of an exemplary user management GUI in one embodiment. In another embodiment, once a GA or PA exists, their administration authority can be modified using the above procedures. Likewise, once a portal user is registered, the user can be added to a user group and associated with a group portal. In one embodiment, the following procedure could be used to manage existing users and groups associated with a portal:
[0060] 1. Select the Portal Management icon 102 in the home page (FIG. 1). The Portal Management home page appears (FIG. 3).
[0061] 2. Select the Group Portal you wish to edit in the Portal Management Home page, the Group Portal Management home page appears (FIG. 5).
[0062] 3. In the User and Group Management section, select User Management 502 . The Edit Users in Group page displays a list of users for the selected group (FIG. 6).
[0063] 4. To remove a user from the group, select the desired user and Select the Remove User From Group button 600 . The user will be removed from the group and will no longer be displayed in the list.
[0064] 5. To delete the user from the system, select the desired user and Select the Delete button 602 . The user is deleted from the system and is removed from the display list.
[0065] 6. To create new users, Select Create New Users 604 .
[0066] 7. To add users to the group, Select Add Users to the Group 606 ; The Add users to Group page displays a list of available users (not shown).
[0067] 8. Select the user you want to add to the group and Select the Add User to Group button (not shown).
[0068] In one embodiment, SA's and PA's can create a new group portal within a portal application. Portals are designed either for single users or for groups. A group portal can restrict portal access to specific visitors and set up delegated administration for portals. There can be multiple group portals within a portal. Group portals can share portal resources, such as layouts and portlets, but can be configured differently to satisfy the needs of each group separately. Because users are designated individually as members of a group, a group portal provides a form of personalization. In one embodiment, the a group portal could be established with the following procedure:
[0069] 1. Select the Portal Management icon 102 in the home page (FIG. 1). The Portal Management Home page appears (FIG. 3).
[0070] 2. Select “Create a New Group Portal” 302 in the Portal Management Home page. A New Group Portal page appears (not shown).
[0071] 3. Enter a display name for the group portal (not shown).
[0072] 4. Select a user group to associate with this group portal (not shown).
[0073] 5. Select a template for the new group portal by selecting a group portal to use as a template (not shown). In one embodiment, templates can specify the layout or location of elements on a portal page.
[0074] 6. In a Create New Group Portal page (not shown), determine the following information:
[0075] a) Whether to Copy Entitlements: You can copy existing entitlements from the template group portal and keep them as is and/or edit them later. You can also choose not to copy the existing entitlements and create new entitlements.
[0076] b) Whether to Copy Group Administrators: When you copy GA's, the same GA's will have the same authority in this group portal as those in the template group portal you have selected. If you choose not to copy the GA's you can assign your own. If you choose to copy the existing GA's you can add to or remove them later.
[0077] In one embodiment, an administrator can select which skin is associated with a group portal. A skin can be a collection of files that includes a cascading style sheet and a directory of images that define the look and feel of a portal. Every button, banner, portlet header, background color, and font characteristic can be determined by the skin. Skins management entails selecting the default skin for a group portal and determining what skins are available to users for customization of their view of a portal. In one embodiment, the following procedure can be followed to specify this information:
[0078] 1. Select the Portal Management icon 102 in the home page (FIG. 1). The Group Portal page appears (FIG. 3).
[0079] 2. Select the Group Portal you wish to edit in the Portal Management Home page, the Group Portal Management Home page appears (FIG. 5). Under Appearance and Content section, Select “Select Skins” 506 . A Select Skins page displays a list of unused and available skins (not shown). The default skin is indicated by an asterisk (*) (not shown).
[0080] 3. To view a thumbnail of a skin, highlight the desired skin. A thumbnail of that skin will appear under the Preview Skin heading (not shown).
[0081] 4. To set a new default, highlight the desired skin and Select Set as Default; the new default skin is marked with an asterisk (*) (not shown).
[0082] 5. You can move skins between the Available and Unused lists by selecting the skin and Selecting the left and right arrows. Making a skin available means that visitors can select that skin when personalizing their portal (not shown).
[0083] [0083]FIG. 7 is an illustration of an exemplary portal page selection GUI in one embodiment. The portal page selection GUI allows an administrator to determine the order in which the page tabs will be displayed. Portal page tabs appear as buttons or tabs on a portal page and act like bookmarks when selected, each able to render a different page within the portal. Portal pages can be thought of as panels or panes that are swapped into and out of a display region of the available portal real estate. In one embodiment, an administrator can select and order pages in a group portal using the following procedure:
[0084] 1. Select the Portal Management icon 102 in the home page (FIG. 1). The Portal Management Home page appears (FIG. 3).
[0085] 2. Select the Group Portal you wish to edit. The Group Portal Management home page appears (FIG. 5).
[0086] 3. In the Group Portal Management Home page, Select “Manage Portlets” 508 , A Pages, Layouts, and Portlets page appears (not shown).
[0087] 4. Select the “Select and Order Pages” link. The Select and Order Pages page displays a list of available and unused pages (FIG. 7). The Home (default) page 700 is indicated by an asterisk (*).
[0088] 5. To reset the Home page, highlight the desired page and Select Set as Home 704 ; the new default page is indicated by an asterisk (*)
[0089] 6. You can move pages between the Available Pages and Unused Pages lists by selecting the page name and selecting the left 708 and right 706 arrows. Making a page available means that visitors may choose to display the page as a tab when personalizing their portal.
[0090] 7. You can reorder pages by selecting the desired page in the Available Pages list and using the Up 710 and Down 712 arrows. This determines the order in which the page tabs will be displayed.
[0091] [0091]FIG. 8 is an illustration of an exemplary portal page attribute GUI in one embodiment. In one embodiment, an administrator can modify the following page attributes:
[0092] a) Available 802 : The page will be available to visitors and can be customized by a user.
[0093] b) Visible 804 : The page will be visible to a visitor default (e.g., the page will have a page tab which, when selected, will render the page).
[0094] c) Mandatory 806 : A visitor will always see this page. That is, they cannot remove it from their personalized portal.
[0095] d) Display Name 808 : The display name for the page, this is the name that visitors will see.
[0096] [0096]FIG. 9 is an illustration of an exemplary page entitlements GUI in one embodiment of the invention. In one embodiment, an entitlement segment is a visitor group based on common characteristics that allows a member of the group to view certain aspects of a portal. An administrator can specify the permissions granted to each entitlement segment as follows:
[0097] a) Can See 906 : Select the radio buttons to grant or deny availability of this page to the entitlement segment members. For example, in FIG. 9 the entitlement segments “Developer” 900 and “Experienced Java Developer” 902 have been granted the ability to see the selected page, whereas the default segment “EVERYONE” 904 , representing users not belonging to the above-mentioned entitlement segments, is denied the ability to see the page.
[0098] b) Can Remove 908 : Select the radio buttons to grant or deny the entitlement segment members the ability to remove the portal page from their view.
[0099] [0099]FIG. 10 is an illustration of an exemplary portlet attributes GUI in one embodiment of the invention. In one embodiment, an administrator can set the following attributes using the GUI:
[0100] a) Available 1000 : The portlet will be available to the visitor.
[0101] b) Visible 1002 : The portlet should be visible to the visitor default.
[0102] c) Minimizable 1004 : The portlet can be minimized by the visitor.
[0103] d) Maximizable 1006 : The portlet can be maximized by the visitor.
[0104] e) Default Minimized 1008 : The portlet is minimized in the visitor default.
[0105] f) Floatable 1010 : The portlet can be opened in a new browser.
[0106] g) Mandatory 1012 : The visitor will always see this page. That is, they cannot remove it from their personalized portal.
[0107] h) Display Name 1014 : The display name for the page, this is the name that site visitors will see.
[0108] [0108]FIG. 11 is an illustration of an exemplary portlet entitlements GUI in one embodiment of the invention. In one embodiment, an entitlement segment is a dynamic user group based on common characteristics that allows a member of the group to view certain aspects of a portal. An administrator can set the following attributes:
[0109] a) Can See 1100 : Check the radio buttons to grant or deny availability of the portlet to the entitlement segment member.
[0110] b) Can Edit 1102 : Check the radio buttons to grant or deny the entitlement segment members the ability to edit the portlet.
[0111] c) Can Remove 1104 : Check the radio buttons to grant or deny the entitlement segment members the ability to remove the portlet from their view. The entitlement segment “Everyone” represents every user in the system and is the default if a user does not fall into an entitlement segment.
[0112] One embodiment may be implemented using a conventional general purpose or a specialized digital computer or microprocessor programmed according to the teachings of the present disclosure, as will be apparent to those skilled in the computer art. Appropriate software coding can readily be prepared by skilled programmers based on the teachings of the present disclosure, as will be apparent to those skilled in the software art. The invention may also be implemented by the preparation of integrated circuits or by interconnecting an appropriate network of conventional component circuits, as will be readily apparent to those skilled in the art.
[0113] One embodiment includes a computer program product which is a storage medium (media) having instructions stored thereon/in which can be used to program a computer to perform any of the features presented herein. The storage medium can include, but is not limited to, any type of disk including floppy disks, optical discs, DVD, CD-ROMs, microdrive, and magneto-optical disks, ROMs, RAMs, EPROMs, EEPROMs, DRAMs, VRAMs, flash memory devices, magnetic or optical cards, nanosystems (including molecular memory ICs), or any type of media or device suitable for storing instructions and/or data.
[0114] Stored on any one of the computer readable medium (media), the present invention includes software for controlling both the hardware of the general purpose/specialized computer or microprocessor, and for enabling the computer or microprocessor to interact with a human user or other mechanism utilizing the results of the present invention. Such software may include, but is not limited to, device drivers, operating systems, and user applications.
[0115] The foregoing description of the preferred embodiments of the present invention has been provided for the purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise forms disclosed. Many modifications and variations will be apparent to the practitioner skilled in the art. Embodiments were chosen and described in order to best describe the principles of the invention and its practical application, thereby enabling others skilled in the art to understand the invention, the various embodiments and with various modifications that are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the following claims and their equivalents. | An interactive tool adapted for administering a portal including user information, comprising providing a graphical user interface (GUI) adapted for managing at least one of the portal and the user information and wherein the GUI can be used to delegate at least one administration task to a user represented by the user information. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application relates to and claims the benefit of prior U.S. Provisional Patent Application No. 60/518,051 entitled Pulse Oximetry Trend Data Storage System, filed Nov. 7, 2003 and incorporated by reference herein.
BACKGROUND OF THE INVENTION
Pulse oximeters have gained rapid acceptance in a wide variety of medical applications, including surgical wards, intensive care units, general wards and home care by providing early detection of decreases in the arterial oxygen supply, reducing the risk of accidental death and injury. FIG. 1 illustrates a pulse oximetry system 100 having a sensor 110 applied to a patient, a monitor 120 , and a patient cable 130 connecting the sensor 110 and the monitor 120 . The sensor 110 has emitters (not shown) and a detector (not shown) and is attached to a patient at a selected fleshy medium site, such as a fingertip 10 as shown or an ear lobe. The emitters are positioned to project light of at least two wavelengths through the blood vessels and capillaries of the fleshy medium. The detector is positioned so as to detect the emitted light after absorption by the fleshy medium, including hemoglobin and other constituents of pulsatile blood flowing within the fleshy medium, generating at least first and second intensity signals in response. A pulse oximetry sensor is described in U.S. Pat. No. 6,256,523 entitled Low Noise Optical Probes, and a pulse oximetry monitor is described in U.S. Pat. No. 6,745,060 entitled Signal Processing Apparatus, both assigned to Masimo Corporation, Irvine, Calif. and both incorporated by reference herein.
The monitor 120 , which may be a standalone device or may be incorporated as a module or built-in portion of a multiparameter patient monitoring system, computes at least one physiological parameter responsive to magnitudes of the intensity signals. A monitor 120 typically provides a numerical readout of the patient's oxygen saturation 122 , a numerical readout of pulse rate 124 , and a display of the patient's plethysmograph 126 , which provides a visual display of the patient's pulse contour and pulse rate.
In one embodiment, the pulse oximetry system 100 has a portable instrument 210 and a docking station 220 , such as described in U.S. Pat. No. 6,584,336 entitled Universal/Upgrading Pulse Oximeter, assigned to Masimo Corporation, Irvine, Calif. and incorporated by reference herein. The portable 210 is a battery operated, fully functional, stand-alone pulse oximeter monitor, as described above, which can be installed into the docking station 220 to expand its functionality.
FIG. 2 illustrates data communications for the portable 210 and docking station 220 . The portable 210 has bi-directional serial data communications with the docking station 220 using universal asynchronous receive, Rx 0 , and transmit, Tx 0 , (UART) signals, and the docking station 220 has bi-directional serial data communications with an external device 230 using Tx 1 and Rx 1 UART signals.
SUMMARY OF THE INVENTION
A conventional pulse oximeter may store trend data that consists of, for example, oxygen saturation and pulse rate. This data is recorded at a low rate, such as 1 Hz. Although the resolution afforded by a low data rate is fine for many patient diagnostic purposes, it is desirable to store the plethysmograph waveform, other pulse oximeter parameters and various internal data at a high rate, such as the sensor signal sampling rate. The resulting high resolution data advantageously assists and/or improves patient condition evaluation, pulse oximetry exception diagnosis and algorithm development. Further, pulse oximetry data is conventionally stored using an external computer or a laptop, which may not always be available or is otherwise cumbersome.
A pulse oximetry data capture system advantageously replaces an external computer with a small data storage device that utilizes removable storage media to hold many hours of high resolution data. In one embodiment, the data storage device is integrated into a docking station for a portable instrument. The removable storage media, having been written with data, can be easily shipped off-site from where the data is collected for later analysis.
One aspect of a pulse oximetry data capture system is a sensor having emitters adapted to transmit light of at least first and second wavelengths into a fleshy medium. A detector is adapted to generate at least first and second intensity signals in response to receiving light after absorption by constituents of pulsatile blood flowing within the fleshy medium. A monitor is configured to input the intensity signals, generate digitized signals from the intensity signals at a sampling rate and compute at least one physiological parameter responsive to magnitudes of the digitized signals. A data storage device is integrated with the monitor and is adapted to record data derived from the digitized signals on a removable storage media at the sampling rate.
Another aspect of a pulse oximetry data capture system is a method having the steps of emitting light of at least first and second wavelengths and detecting the light after absorption by a fleshy tissue site so as to generate a corresponding sensor signal. Additional steps are digitizing at a sampling rate, demodulating the sensor signal so as to generate a plethysmograph, and calculating at least oxygen saturation and pulse rate from the plethysmograph. A further step is writing data to the removable media. The data comprises the plethysmograph at the sampling frequency along with the oxygen saturation and the pulse rate at a sub-sampling frequency.
A further aspect of a data capture system has a sensor adapted to generate an intensity signal responsive to light absorption by constituents of pulsatile blood flowing within a fleshy medium. A digitizer inputs the intensity signal and generates a digital plethysmograph signal at a sampling rate. A signal processor inputs the plethysmograph and calculates an oxygen saturation and pulse rate. A storage media is configured to removably load into a data storage device. The data storage device inputs the plethysmograph, oxygen saturation and pulse rate and writes the plethymograph to the storage media at the sampling rate, along with the oxygen saturation and the pulse rate at a sub-sampling rate.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a prior art pulse oximetry system having a portable pulse oximeter and a docking station;
FIG. 2 is a block diagram of portable and docking station data communications;
FIG. 3 is a general block diagram of a pulse oximetry data capture system;
FIG. 4 is a block diagram of a pulse oximetry docking station incorporating a data capture system;
FIGS. 5A-E are front, front perspective, back, side and internal top views, respectively, of a pulse oximetry docking station incorporating a data capture system;
FIG. 6 is a program flow diagram for a pulse oximetry data capture system; and
FIG. 7 is a table illustrating a multiple byte message package.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 3 illustrates a pulse oximetry data capture system 300 having a digitizer 310 , signal processor 320 , a data storage device 330 , a removable media 340 and a data port interface 350 . The digitizer 310 samples the sensor signal 301 based upon a predetermined sampling frequency 302 and performs an analog-to-digital conversion of the sampled signal to generate a digitized sensor signal 312 . The signal processor 320 demodulates the red (RD) and IR components of the digitized sensor signal 312 into RD and IR plethysmograph signals and operates on those plethysmograph signals so as to calculate oxygen saturation and pulse rate. A pulse oximetry demodulator is described in U.S. Pat. No. 6,643,530 entitled Method and Apparatus for Demodulating Signals in a Pulse Oximetry System, assigned to Masimo Corporation, Irvine, Calif. and incorporated by reference herein. As a result, the signal processor 320 generates a data stream 322 comprising plethysmograph, oxygen saturation and pulse rate values among other data. The data storage device 330 inputs the data stream 322 , which is recorded on the removable media 340 . The data stream 322 may also be provided to an external device via the data port interface 350 . In various embodiments, the data storage device 330 may transparently “pass-through” the data stream 322 to other system components, such as the data port interface 350 , or it may otherwise tap the data stream 322 as it is utilized elsewhere in the system 300 . Alternatively, the signal processor 320 or other system components may provide the data storage device 330 with a dedicated data stream used solely for data recording purposes.
In one embodiment, the data stream 322 comprises raw, filtered and/or scaled plethysmograph waveform data; computed output data such as oxygen saturation, pulse rate, signal strength and signal quality; and other system data such as sensor status, monitor status, monitor settings, alarms, and internal algorithm parameters and variables. Pulse oximetry signal strength and signal quality or confidence data are described in U.S. Pat. No. 6,463,311 entitled Plethysmograph Pulse Recognition Processor and U.S. Pat. No. 6,684,090 entitled Pulse Oximetry Data Confidence Indicator, both assigned to Masimo Corporation, Irvine, Calif. and both incorporated by reference herein. Sensor status, monitor status and settings and alarms are described in U.S. Pat. No. 6,658,276 entitled Pulse Oximeter User Interface, also assigned to Masimo Corporation and incorporated by reference herein.
FIG. 4 illustrates a docking station embodiment 400 of a data capture system 300 ( FIG. 3 ). A docking station 401 has a CPU 410 , a data storage device 420 and an associated removable storage media 430 . The docking station communicates with a portable pulse oximeter via input UART signals 402 and with an external device via output UART signals 403 . The docking station CPU 410 communicates with the data storage device 420 using internal UART signals 412 . The CPU 410 receives pulse oximetry and related data from the portable via the input UART signals 402 and may generate additional data in response. The received portable data and/or the CPU generated data is transmitted to the data storage device 420 via the internal UART signals 412 and recorded on the removable media 430 accordingly, as described in further detail below.
FIGS. 5A-E illustrate a particular docking station embodiment 500 of a pulse oximetry data capture system 400 ( FIG. 4 ). The data storage device 520 ( FIG. 5E ) is a Flashcore-B available from TERN, Inc., Davis, Calif., and the removable storage media 530 ( FIG. 5E ) is a 256 MB Compact Flash card. The data storage device 520 is installed internally to the docking station 510 adjacent a circuit board 540 ( FIG. 5E ) and proximate the docking station bottom 501 . The docking station 510 supplies power to the data storage device 520 . The data storage device 520 transparently passes-through the internal UART signals 412 ( FIG. 4 ) to the output UART signals 403 ( FIG. 4 ). A slot 550 is created in the bottom of the docking station 510 , which allows insertion and removal of the storage media 530 into and out of the storage device 520 . One of ordinary skill will recognize that the data storage device 520 and associated removable media 530 can utilize various data storage technologies other than Compact Flash, such as Memory Stick, SmartMedia, Secure Digital Card, USB Flash Disk and MicroDrive to name just a few.
FIG. 6 illustrates program flow 600 for the docking station CPU to control and write data to the data storage device 520 ( FIG. 5E ). To start, a flash card 530 ( FIG. 5E ) is validated and initialized 610 . If a valid flash card is in the data storage device, then the card capacity is checked 620 . If the card capacity is sufficient, then a file is opened 630 and data writing begins 640 . Data is advantageously written to the data storage device in multiple byte message packets at up to the IR and red signal sampling rate, as described with respect to FIG. 7 , below. The writing time is checked 650 . After one hour of data is recorded, the card capacity is rechecked 620 and, if sufficient, another file is opened 630 and recording continues. If an error occurs in opening a file, an LED indicator is flashed 660 . If no valid flash card is detected, data is passed through to the external device signal lines and the LED indicator is turned on 670 . If there is insufficient flash card capacity, the oldest file is deleted 680 .
FIG. 7 illustrates a multiple byte message packet having start of message (SOM) 710 , end of message (EOM) 720 , sequence (seq) 730 and check sum (CSUM) 770 bytes and one or more data segments d 1 -d 2 740 , w 0 -w 7 750 and x 0 -xm 760 . The SOM 710 and EOM 720 are fixed-value bytes that delineate each message packet. The seq 730 byte identifies specific message packets in a cyclical group of message packets, as described below. The data segments 740 - 760 are formatted so as to allow storage of the data stream 322 ( FIG. 3 ) described above. The check sum 770 is for communications error detection and is the sum of the data bytes 740 - 760 modulo 256 . The message packets 700 are transmitted to the data storage device 420 ( FIG. 4 ) and stored on the removable storage media 430 ( FIG. 4 ) at about the IR and red (RD) signal sampling rate. In this manner, sufficient information with sufficient resolution is stored on the removable storage media for a thorough external data analysis.
In one embodiment, 32-bit IR waveform data can be stored in w 0 -w 3 750 , 32 -bit RD waveform data can be stored in w 4 -w 7 750 , and various 16-bit output data, such as oxygen saturation and pulse rate can be stored in d 1 -d 2 740 as identified by the sequence byte 730 . In a particular embodiment, the sampling rate is 62.5 Hz, and 62 messages packets are stored in a specific sequence per second. The sequence byte (seq) 730 increments from 1 to 62 with each successive message packet 700 and then resets to 1, repeating so as to identify the specific data in, say, d 1 -d 2 740 . For example, plethysmograph waveform data is stored in w 0 -w 7 750 at a 62 Hz rate and oxygen saturation, corresponding to seq=1 and pulse rate, corresponding to seq=2, are stored in d 1 -d 2 740 at a sub-sampling rate of 1 Hz.
A pulse oximetry data capture system 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 the art will appreciate many variations and modifications. | A data capture system utilizes a sensor with emitters adapted to transmit light into a fleshy medium and a detector adapted to generate intensity signals in response to receiving light after absorption by the fleshy medium. A monitor is configured to input the intensity signals, generate digitized signals from the intensity signals at a sampling rate and compute at least one physiological parameter responsive to magnitudes of the digitized signals. A data storage device is integrated with the monitor and is adapted to record data derived from the digitized signals on a removable storage media at the sampling rate. | 0 |
BACKGROUND
The present application is a continuation-in-part of co-pending U.S. application Ser. No. 11/264,940, filed Nov. 2, 2005 and entitled “SYSTEM FOR FILTERING STORMWATER-CARRIED DEBRIS FLOWING THROUGH A GUTTER INLET INTO A CATCH BASIN,” which is incorporated herein by reference in its entirety.
The present invention relates generally to stormwater drainage systems and, more particularly, to a novel system for filtering sediment and debris from stormwater flowing through a gutter inlet and gravitationally therefrom into a catch basin therebelow.
Stormwater drainage systems are commonplace and, indeed, are mandated for virtually all new building construction subject to the regulations of municipal and county building codes throughout the United States. Essentially, a stormwater drainage system comprises a series of catch basins strategically located according to the topography of a given region under development, with the catch basins emptying into drainage pipes leading to existing streams, creeks, lakes or rivers. In the construction of streets in new building developments, catch basins are required to be constructed below grade alongside the streets to receive stormwater runoff via basin inlets formed in roadside storm gutters.
The growing awareness of environmental conservation issues over recent decades has raised awareness of the significant erosion of bare land which can occur during the course of building construction as a result of stormwater drainage over the bare land. Eroded soil in the form of silt and sediment along with other debris can be carried in significant quantities by stormwater runoff along street gutters and into stormwater drainage systems, sometimes to such a significant extent to clog stormwater catch basins and drainage pipes, and in any event taxing the capacities of and polluting existing streams, creeks, lakes and rivers. As a result, most building codes regulated by municipalities and county building offices have implemented regulations requiring various steps to be taken to prevent or at least mitigate stormwater erosion of soil during building construction, including steps such as the erection of silt fences.
Despite these measures, stormwater runoff still carries a not insignificant amount of silt, sediment and other debris into storm drainage systems. As a result, some form of filtering device is now generally required to be installed in gutter inlets into stormwater catch basins during the course of construction projects to attempt to prevent such debris from entering stormwater drainage systems. Various such filtration devices have been proposed, including for example devices described in U.S. Pat. Nos. 5,403,474; 5,632,888; 5,954,952; 6,709,579; and 6,824,677 and published U.S. Patent Application No. 2004/0112811. While many of these devices may be generally effective for their intended purpose and function, the devices which have achieved commercial use tend to be disadvantageously heavy, bulky and unwieldy. Furthermore, in order to brace against the force generated by stormwater runoff, which can be significant during periods of heavy rain, the filtering medium commonly used in these devices tends to be heavy to assist in holding the devices in place. In turn, the filtration medium also tends to impede the free flow of the stormwater runoff which can result in flooding of the adjacent gutters and streets as water is restricted from entering the catch basins.
SUMMARY OF THE INVENTION
It is accordingly an object of the present invention to provide a system for filtering debris carried by stormwater flowing through a gutter inlet into an associated catch basin which addresses the disadvantages of the known prior art. A more particular object of the present invention is to provide a stormwater debris-filtering system which enables the use of low density, lightweight filtration media. Another object of the present invention is to provide a stormwater debris-filtering system which is relatively easy to install at a gutter inlet and will resist the forces of water flowing through the filtering media so as to remain securely in place. Still another object of the present invention is to provide a stormwater debris-filtering system which permits excess stormwater runoff to enter the gutter inlet as the level of water runoff rises above the height of the filtering system.
Briefly summarized, the stormwater debris-filtering system of the present invention utilizes a filter device configured in conformity to the gutter inlet to substantially cover the gutter inlet exteriorly of the catch basin without passing through the gutter inlet into the catch basin. The filter device is comprised of filtration media selected to prevent passage through the filter device of soil, silt, leaves, sticks and other stormwater-carried debris, while permitting substantially free passage through the filter device of stormwater. A retainer device is provided for maintaining the filter device in covering relation to the gutter inlet. More specifically, the retainer device is attached to the filter device and configured to extend through the gutter inlet and to depend gravitationally downwardly therefrom within the catch basin. The retainer device is weighted sufficiently to gravitationally pull the filter device securely against the gutter inlet to resist dislodgement under the forces of stormwater flowing therethrough.
It is contemplated that any of various types of filtration media may be utilized in the present invention, and selected according to the particular filtration needs of a given application or environment. It is contemplated that, in various embodiments, it will be desirable for the filtration media to be of a lightweight material having a lesser density than water, such as a filtration media made of a polymeric material, e.g., an expanded polymeric bead material such as expanded polystyrene.
Preferably, the filter device comprises a flexible tubular fabric sock, e.g., of an elongate cylindrical shape, for containing the filtration media. The tubular fabric sock together with the filtration media is preferably deformable into conformity to the gutter inlet. In this manner, the filter device is enabled to conform to the gutter inlet so as to prevent debris-laden stormwater from entering the gutter inlet without flowing through the filter device.
The retainer device may be of various shapes and forms. In one contemplated embodiment, the retainer device comprises a sleeve portion configured to receive the filter device extended longitudinally therethrough and a sack portion for containing a weighting material, such as sand, gravel or soil.
In one contemplated embodiment, the stormwater debris-filtering system of the present invention may further comprise an overflow device for positioning at least a portion of the filter device a distance from the upper exterior periphery of the gutter inlet. The overflow device is arranged adjacent the filter device to facilitate passage of excess stormwater over the filter device and through the gutter inlet. In accordance with one preferred aspect, the overflow device comprises a cushion filled with the filtration media. In accordance with another preferred aspect, the overflow device comprises a sleeve portion configured to receive the filter device extended longitudinally therethrough.
Other various embodiments of the stormwater debris-filtering system of the present invention will be recognizable and understood to persons knowledgeable and skilled in the relevant industry and are intended to be within the scope of the present invention. Without limiting the scope and substance of the invention, further details, features and advantages of the invention will be described and understood from a description of a preferred embodiment as presently contemplated, set forth in the following specification with reference to, the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the stormwater debris-filtering system of the present invention, with the filter device exploded from the retainer device;
FIG. 2 is a perspective view depicting the stormwater debris-filtering system of FIG. 1 in assembled condition and in the process of being installed into operational disposition in a representative gutter inlet and associated catch basin;
FIG. 3 is a perspective view similar to FIG. 2 , depicting the stormwater debris-filtering system of the present invention as fully installed in the gutter inlet and associated catch basin;
FIG. 4 is a vertical cross-sectional view of the installed stormwater debris-filtering system of FIG. 3 , taken along line 4 - 4 thereof vertically through the gutter inlet, the filtering system, and the catch basin;
FIG. 5 is a perspective view of the stormwater debris-filtering system of FIG. 1 with an overflow device positioning the filter device a distance from the upper periphery of the gutter inlet;
FIG. 6 is a perspective view depicting the stormwater debris-filtering system of FIG. 5 in assembled condition and in the process of being installed into operational disposition in a representative gutter inlet and associated catch basin;
FIG. 7 is a perspective view of the stormwater debris-filtering system of FIG. 5 as fully installed in the gutter inlet and associated catch basin; and
FIG. 8 is a vertical cross-sectional view of the installed stormwater debris-filtering system of FIG. 7 , taken along line 8 - 8 thereof vertically through the gutter inlet, the filtering system, the overflow device, and the catch basin.
DETAILED DESCRIPTION
Referring now to the accompanying drawings and initially to FIG. 1 , the system of the present invention for filtering stormwater-carried debris is indicated overall in FIG. 1 by reference numeral 10 and basically comprises a conformable filter device 12 attachable to a weighted retainer device 14 .
The filter device 12 may be of any of various constructions and configurations so as to be conformable to the shape and size of a gutter inlet of a conventional form of stormwater catch basin. In a presently contemplated embodiment, the filter device 12 may be of an elongate cylindrical shape and sufficiently flexible and deformable to generally mold into conformity to the gutter inlet. In the embodiment as illustrated in FIG. 1 , the filter device 12 comprises an elongate flexible tubular fabric sock 16 of an open mesh geotextile fabric structure so as to readily permit stormwater to flow therethrough. A quantity of filter media 18 is contained within and fully occupies the filter sock 16 . The filter media 18 may be of any of various types, selected to permit substantially free flow of stormwater through the filter media while separating from the stormwater any debris, such as soil, silt, leaves, sticks, and the like carried by the stormwater. While various filter media will provide satisfactory results, one type of filter media which is believed to be quite advantageous is an expanded polymeric bead material, such as expanded polystyrene beads, which offer the advantage of being light weight, while performing efficient filtration of all types of debris with minimal inhibition of water flow through the media.
The retainer device 14 may be of any suitable construction adapted to attach to the filter device and to have sufficient weight to hang gravitationally downwardly from the filter device through a gutter inlet into a catch basin, as described more fully hereinafter. In the embodiment illustrated, the retainer device 14 includes an attachment portion 20 in the form of an open-ended tubular mesh fabric sleeve sized to allow the filter device 12 to be snugly inserted longitudinally through the attachment portion 20 . The illustrated embodiment of the retainer device 14 further includes a weighted portion 22 fixed to the attachment portion 20 and configured to pass through a gutter inlet and to depend gravitationally downwardly from the gutter inlet into an associated catch basin. The weighted portion 22 in the illustrated embodiment is preferably in the form of a sack fabricated of a high strength flexible fabric material, such as a tightly woven geotextile material, which can contain a quantity of a weighting material such as sand, gravel or a similar material representatively indicated at 24 .
The installation and use of the stormwater debris-filtering system 10 of the present invention may best be understood with reference to FIGS. 2-4 of the drawings. In each drawing, a representative form of a conventional stormwater drainage system is schematically depicted wherein a roadside stormwater drainage gutter 26 is formed with a gutter inlet 28 to drain stormwater runoff gravitationally into a catch basin 30 situated immediately beneath the inlet 28 and communicating with a stormwater drainage pipe 32 to transport the runoff stormwater into a natural water collection area, such as a nearby creek, stream, pond, river, etc. The filtering system 10 is assembled with at least one retainer device 14 attached to the filter device 12 and with a sufficient quantity of the weighting material 24 contained within the weighted portion 22 of the retainer device 14 . Multiple retainer devices 14 may be utilized in the case of a gutter inlet of significant length requiring a correspondingly long filter device 12 . The weighted sack portion 22 of the retainer device 14 is then inserted through the gutter inlet 28 so as to hang therefrom gravitationally downwardly into the catch basin 30 . Before releasing the retainer device 14 , the elongate filter device 12 is positioned to extend fully along the entire length of the gutter inlet 28 . The retainer device 14 is then released, whereby its weight pulls the filter device 12 gravitationally against the gutter inlet. The flexibility of the outer fabric sock 16 together with the deformability of the filter media 18 within the filter sock 16 enables the filter device 12 to mold conformingly to the shape and configuration of the opening of the gutter inlet 28 , thereby essentially closing the inlet 28 against entry of stormwater runoff except by flow through the filter sock 16 and filter media 18 .
In another contemplated embodiment of the present invention, shown in FIGS. 5-8 , the stormwater debris-filtering system may include an overflow device 34 adapted to be attached adjacent to the filter device 12 . With respect to some particularly heavy storms, the volume of stormwater may be sufficiently high so as to exceed the height of the filter device 12 . In such instances, the overflow device 34 is positioned with respect to the gutter inlet to separate at least a portion of the filter device 12 from the upper periphery of the gutter inlet 28 , thus permitting excess stormwater runoff arising from particularly high stormwater volume to pass over the filter device 12 and through the gutter inlet 28 to the catch basin 30 .
The overflow device 34 may be of any various size and configuration so as to sufficiently separate at least a portion of the filter device 12 from the upper periphery of the gutter inlet 28 by some selected distance. In accordance with one embodiment, shown in FIG. 5 , the overflow device 34 is a pillow-like cushion composed of a geotextile fabric structure that permits stormwater to flow therethrough. The fabric structure of the overflow device 34 preferably has a durable quality to withstand abrasion and repeated use during heavy storm activity or other instances of high stormwater volume. Moreover, the fabric structure of the overflow device 34 may be sufficiently flexible and deformable so as to generally conform with various shapes and sizes of gutter inlets, and particularly at the upper periphery thereof. Advantageously, as shown in FIG. 5 , the overflow device 34 may be filled with the same or similar filter media 18 as is contained within the filter sock 16 so as to provide additional filtration for excess stormwater runoff exceeding the height of the filter device 12 that enters into contact with the overflow device 34 .
The size of the overflow device 34 may be selected to reflect the size of the gutter inlet 28 and the amount of excess stormwater runoff that might be expected at or near the drainage gutter 26 . In some areas where a stormwater debris-filtering system may be necessary or helpful, the size of the overflow device 34 may be relatively small in relation to the size of the gutter inlet 28 . In such instances, a small gap between the filter device 12 and the upper periphery of the gutter inlet 28 may be sufficient to provide the necessary relief in the event that some excess stormwater accumulates. However, in some areas where the amount of excess stormwater volume is expected to be particularly heavy, features of the overflow device 34 , such as the depth, may be adjusted so as to permit a greater volume of excess stormwater to pass unimpeded over the filter device 12 , through the gutter inlet 28 , and into the catch basin 30 . For instance, the depth of the overflow device 34 may be increased so as to position the filter device 12 at a greater distance from the inlet 28 , thus facilitating the passage of a greater volume of excess stormwater runoff over the filter device 12 , through the inlet 28 , and into the catch basin 30 . Additionally, a plurality of overflow devices may be used in association with a filtering system 10 .
The overflow device 34 may be affixed to an attachment portion 20 in the form of an open-ended tubular mesh fabric sleeve sized to allow the filter device 12 to be snugly inserted longitudinally through the attachment portion. In accordance with a preferred construction of this embodiment, shown in FIG. 5 , the overflow device 34 may be attached to the attachment portion 20 of the retainer device 14 such that each of the overflow device 34 and the weighted sack portion 22 of the retainer device 14 are attached to the attachment portion 20 at the same location so as to facilitate joint attachment of each of the retainer device 14 and the overflow device 34 to the filter device 12 . It is also within the scope of the present invention that the overflow device 34 may be attached to the filter device 12 by a separate attachment portion or may be attached to the filter device 12 directly.
With reference to FIGS. 6-8 , installation and use of the stormwater debris-filtering system 10 with an overflow device 34 may thus be understood. The filtering system 10 is assembled with at least one retainer device 14 attached to the filter device 12 and with a sufficient quantity of the weighting material 24 contained within the weighted portion 22 of the retainer device 14 . Multiple retainer devices 14 may be utilized in the case of a gutter inlet of significant length requiring a correspondingly long filter device 12 . The weighted sack portion 22 of the retainer device 14 is then inserted through the gutter inlet 28 so as to hang therefrom gravitationally downwardly into the catch basin 30 . Before releasing the retainer device 14 , the elongate filter device 12 is positioned to extend fully along the entire length of the gutter inlet 28 . The overflow device 34 is positioned to extend away from the filter device 12 such that the overflow device 34 is nestled between the filter device 12 and the gutter inlet 28 and rests against the upper exterior periphery of the gutter inlet 28 . The retainer device 14 is then released, whereby its weight pulls the filter device 12 gravitationally against the gutter inlet 28 . The flexibility of the outer fabric sock 16 together with the deformability of the filter media 18 within the filter sock 16 enables the filter device 12 to mold conformingly to the shape and configuration of the opening of the gutter inlet 28 . The overflow device 34 pushes at least a portion of the upwardly facing extent of the filter device 12 away from the length of the gutter inlet 28 so as to create a gap between the upwardly facing extent of the filter device 12 and the upper extent of the inlet 28 , while maintaining the downwardly facing extent of the filter device 12 in contact with the gutter 26 . The filtering system 10 thereby substantially closes the gutter inlet 28 against entry of stormwater runoff except by flow through the filter sock 16 , the overflow device 34 , and filter media 18 contained in each of the filter sock 16 and overflow device 34 , and by entry of excess stormwater through the gap between the filter device 12 and the upper periphery of the gutter inlet 28 and into the catch basin 30 .
Advantageously, the filtering system of the present invention enables substantially greater flexibility in the selection of varying types of filtering media without concern for the media having sufficient mass and weight to withstand undesired movement under the force of flowing stormwater runoff and, in turn, the filter media may be selected according to the criteria of optimizing the balance between the promotion of substantially free water flow through the device and filtration efficiency in removing silt and other debris. Thus, the present invention enables the use of lightweight, low density polymeric filter material which has not been possible with known filtration devices. In turn, the filtering system of the present invention is easier to handle and to install than known devices while still providing improved results.
It will therefore be readily understood by those persons skilled in the art that the present invention is susceptible of 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 embodiments, adaptations, variations, modifications and equivalent arrangements, the present invention being limited only by the claims appended hereto and the equivalents thereof. | A system for filtering debris carried by stormwater flowing through a gutter inlet into a catch basin utilizes a filter device configured to conform to and to substantially cover the gutter inlet and a retainer device for maintaining the filter device in place covering the gutter inlet. The retainer device is attached to the filter device and configured to extend through the gutter inlet to hang gravitationally downwardly into the catch basin. The retainer device is weighted to gravitationally pull and hold the filter device securely against the gutter inlet against dislodgement under the forces of flowing stormwater. | 4 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention relates generally to surgical clamps, and more specifically to blood vessel occlusion clamps.
[0003] 2. Discussion of the Prior Art
[0004] Surgical occlusion clamps are commonly used to close off or occlude body conduits, such as blood vessels. A common variety of vessel occlusion clamp is that referred to as a “Bahnson” clamp, which has small metal handles that operate a pair of opposing jaws. When the jaws are brought into close proximity on either side of a vessel, the vessel is squeezed against itself to achieve at least partial occlusion. It is of particular importance that the jaws of the clamp be stable, and sufficiently inflexible that the jaws do not cross over or scissor, but rather press directly against each other along their length to occlude any conduit disposed between the jaws.
[0005] It is also desirable to have a thin, low-profile jaw design that can access narrow areas. In the past, this desire for a low-profile design has worked against the need for stability in the jaws. Jaw inserts have been provided, but typically have had exposed edges, ends, and corners, which tend to entrap or entangle surgical sutures.
SUMMARY OF THE INVENTION
[0006] In accordance with the present invention, a vessel occlusion clamp of the Bahnson type is provided with improved stability and reduced flexibility, while maintaining a low-profile jaw design. In a preferred embodiment of the clamp, the jaws are provided with a receding or tapered T-beam cross section, which greatly reduces the bendibility or flexibility of the jaws. Other dimensional-shaped cross sections of interest include a U-beam cross section, an I-beam cross section, a trapezoidal I-beam cross section, a continuous or whole-length T-beam cross section, a B-channel cross section, and an L-beam cross section. With the dimensional-shaped, cross section design, beam stiffness is substantially increased, while transverse deflection is greatly reduced. In addition, the transverse members forming the beam cross sections can be relied on to provide shielding of the jaw insert edges. This shielding prevents entrapment or entanglement of surgical sutures. Scallops or hollowed recesses can be provided in the jaws to facilitate installation and removal of the inserts without degrading structural jaw stability.
[0007] In one aspect of the invention a surgical clamp is adapted for use in occluding a body conduit. The clamp includes a first jaw, and a second jaw movable relative to the first jaw in a generally parallel relationship. A handle assembly is operable to move the first and second jaws relative to each other between a spaced position and a proximate position. The first jaw has an elongate configuration characterized by a length and a width. First portions of the first jaw have in radial cross section a first shape which remains generally constant in area along the length of the first jaw. Second portions of the first jaw have in cross section a second shape which changes in area along the length of the first jaw. The first portions will typically have a first width while the second portions will have a second width greater than the first width. An insert is adapted to be removably mounted on the first portions with the second portions extending laterally of the insert.
[0008] In a further aspect of the invention, the surgical clamp includes a handle assembly and a pair of opposing jaws movable by the handle assembly in a plane of operation between a spaced orientation, wherein the jaws are spread to recede the body conduit, and a proximal orientation wherein the jaws are substantially closed to occlude the body conduit. At least one of the jaws has in cross section a non-rectangular configuration. An insert having a first width is carried by first portions of the jaw which have a second width. Second portions of the jaw have a third width which defines with the first portions the thickness of the jaw. The first width of the insert is less than the third width of the second portions and greater than the second width of the first portions.
[0009] These and other features and advantageous of the invention will be better understood with a description of preferred embodiments and reference to the associated drawings.
DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 is a front side perspective view of a vessel occlusion clamp of the Bahnson type, illustrating disposable inserts mounted on parallel jaws having a dimensional-shaped, cross section design;
[0011] FIG. 2 is a perspective view similar to FIG. 1 , showing the jaws with the disposable inserts removed;
[0012] FIG. 3 is a side-elevation view of a clamp jaw illustrating a tapered, T-beam cross section;
[0013] FIG. 4 is a cross section view taken along lines A-A of FIG. 3 ;
[0014] FIG. 5 is a cross section view taken along lines B-B of FIG. 3 ;
[0015] FIG. 6 is a cross section view similar to FIG. 5 and illustrating a trapezoidal I-beam cross section;
[0016] FIG. 7 is a cross section view similar to FIG. 5 and illustrating a U-channel cross section;
[0017] FIG. 8 is a cross section view similar to FIG. 5 and illustrating a V-beam cross section;
[0018] FIG. 9 is a cross section view similar to FIG. 5 and illustrating an I-beam cross section; and
[0019] FIG. 10 is a cross section view similar to FIG. 5 and illustrating an L-beam cross section.
DESCRIPTION OF PREFERRED EMBODIMENT
[0020] A vascular occlusion clamp of the Bahnson type is illustrated in FIG. 1 and designated generally by the referenced numeral 10 . The clamp 10 includes a pair of handles 12 and 14 with a ratchet lock 16 , which pivot on a fulcrum 18 to move jaws 21 and 23 in a generally parallel relationship. Disposable inserts 25 and 27 are removably mounted on the associated jaws 21 , 23 . In FIG. 2 , the inserts 25 and 27 have been removed in order to illustrate the dimensional-shaped design of the jaws 21 and 23 . From this view it can be seen that the jaws 21 and 23 extend along a Z axis but move generally along an X axis. The width of the jaws is measured along a Y axis. Thus the jaws having a length along the Z axis, a width along the Y axis, and a thickness along the X axis.
[0021] This dimensional-shaped design is further illustrated in the side-elevation view of FIG. 3 and the associated cross sectional views of FIGS. 4 and 5 . The side elevation view of FIG. 3 is drawn in the YZ plane while the cross sectional views of FIGS. 4 and 5 are drawn in the XY plane. In all of the cross sectional views of FIGS. 4-10 , a preferred disposition of the associated insert 25 is illustrated in dotted lines.
[0022] In this embodiment, the jaw 21 has an engagement section 29 with a generally constant profile along its length. This engagement section 29 is intended to occupy a channel within the associated insert 25 . The jaw 21 also includes a support section 31 which, in cross section forms a T with the elongate section 29 . It is this support section 31 that provides this embodiment with its dimensional-shaped structure. In this case, the support section 31 tapers from a narrow width at the distal end of the jaw 21 to a maximum width near the proximal end of the jaw 21 . With this dimensional-shaped configuration, the cross section of the jaw 21 is provided with substantially increased beam stiffness along the X axis and reduced transverse deflection along the Y axis.
[0023] The support section 31 can also be relied on to shield the edges, ends, and corners of the insert 25 that can entrap or entangle surgical sutures. With the shielding provided by these transverse elements, the edges, ends, and corners are not as prominent. While this prevents entrapment of surgical sutures, it can also make it more difficult to remove the inserts 25 and 27 for disposal. It is for this reason that the embodiment of FIG. 3 is provided with scallops or hollow recesses 33 and 35 , which provide shallow access to a proximal edge of each insert. With these recesses 33 and 35 provided in proximity to counterbored pin recesses 37 , 39 ( FIG. 2 ), the inserts 25 and 27 can be easily engaged and removed.
[0024] Other dimensional-shaped cross sectional designs providing these advantages are illustrated in FIGS. 6-10 . Each of these non-rectangular shaped cross sections provide increased beam stiffness and reduce transverse deflection, compared to the rectangular cross sections of prior designs.
[0025] In the embodiment of FIG. 6 , the jaw 21 has a trapezoidal I-beam shape characterized by an inner flange 41 joined to an outer flange 43 by a center flange 45 . In this case, the inner flange 41 and the center flange 45 formed the engagement section 29 which is disposed in the channel of the insert 25 . The outer flange 43 forms the support section 31 and maintains an abutting relationship with the insert 25 . This I-beam shape has a trapezoidal configuration in that the inner flange 41 has a width less than the outer flange 43 .
[0026] In the embodiment of FIG. 7 , the jaw 21 in cross section has a generally U-shaped configuration. A center flange 50 is supported by two side flanges 52 and 54 which extend to outwardly directed flanges 56 and 58 respectively. In this embodiment, the center flange 50 and side flanges 52 and 54 form the engagement section 29 while the outwardly directed flanges 56 and 58 form the support section 31 . As in previously embodiments, the engagement section 29 is received within a center channel of the insert 25 while the support section 31 is disposed in an abutting relationship with the insert 25 .
[0027] The embodiment of FIG. 8 includes a jaw 21 having in cross section a V-shaped configuration. This embodiment includes a top flange 61 supported by side flanges 63 and 65 which extend to outwardly directed flanges 67 and 69 , respectively. In this embodiment, the side flanges 63 and 65 are disposed at an acute angle with respect to the top flange 61 and are also disposed at an angle with respect to each other. The top flange 61 and side flanges 63 and 65 form the engagement section 29 and are adapted to be disposed within a channel of the insert 25 . The outwardly directed flanges 67 and 69 form the support section 31 and are disposed in an abutting relationship with the insert 25 .
[0028] The embodiment of FIG. 9 includes a jaw 21 , having in cross section an I-Beam shape similar to that of FIG. 6 . Thus, the jaw 21 has a top flange 72 , joined to a bottom flange 74 by a center flange 76 . In this embodiment, the top flange 72 has the same width as the bottom flange 74 , but a greater thickness than the bottom flange 74 . Also, the flanges 72 , 74 and 76 are all disposed within the channel of the insert 25 . Accordingly, these three flanges in the illustrated embodiment form the engagement section 29 of the jaw 21 .
[0029] In the embodiment of FIG. 10 , the jaw 21 in cross section has a U-shaped configuration. This embodiment is characterized by a bottom flange 81 , side flanges 83 and 85 , and a center flange 87 . The side flanges 83 and 85 are equally spaced from the bottom flange 87 and extend from a side of the bottom flange 81 , opposite to that of the center flange 87 . Outwardly directed flanges 89 and 91 extend from the bottom flange 81 outwardly of the side flanges 83 and 85 . In this embodiment, portions of the bottom flange 81 together with the side flanges 83 and 85 form the engagement section 29 . The remaining portions of the bottom flange 81 together with the outwardly directed flanges 89 and 91 and the bottom flange 87 form the support section 31 .
[0030] The resulting clamp 10 maintains the desired low profile jaw design, while the dimensional-shaped cross sections provide increased stiffness and reduced flexibility. As a result, transverse deflection is substantially avoided. The dimensional-shaped cross section also provides shielding to prevent entanglement of surgical sutures, while the scalloped and hollowed recessed 33 and 35 facilitate removal of the inserts 25 and 27 .
[0031] Many alterations and modifications can be made to the foregoing preferred embodiments without departing from the spirit and scope of the invention. Therefore it must be understood that the illustrated embodiments have been set forth only by way of example, and should not be taken as limiting the invention. For example, notwithstanding the fact that the claims set forth below recite certain elements and combinations, it must be expressly understood that the invention includes other combinations of fewer, more or different elements, which are not disclosed above even when not initially claimed in such combinations.
[0032] In addition, the words used in this specification to describe the invention and its various embodiments are to be understood not only in the sense of their commonly defined meanings, but also in the sense of any special definitions used in this specification, which may extend beyond the scope of the commonly defined meanings. Thus if an element can be understood in the context of this specification as including more than one meaning, than its use in the claims must be understood as being generic to all possible meanings supported by the specification and by the word itself.
[0033] The definitions of the words or elements of the following claims are, therefore, defined in the specification to include not only the combination of the elements which are literally set forth, but all equivalent structure, material or method steps for performing substantially the same function, in substantially the same way, to obtain substantially the same way to obtain substantially the same result. In this sense it is therefore contemplated that an equivalent substitution of two or more elements may be made for any one of the elements in the claims below or that a single element may be substituted for two or more elements in a claim.
[0034] Insubstantial changes from the claimed subject matter, now known or later devised, are expressly contemplated as being equivalently within the scope of the claims. Therefore, obvious substitutions now or later known to one with ordinary skill in the art are deemed to be within the scope of the defined elements.
[0035] 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 essentially incorporates the idea of the invention. Many alterations and modifications can be made to the foregoing preferred embodiments without departing from the spirit and scope of the invention. Therefore it must be understood that the illustrated embodiments have been set forth only by way of example, and should not be taken as limiting the invention. For example, notwithstanding the fact that the claims set forth below recite certain elements and combinations, it must be expressly understood that the invention includes other combinations of fewer, more or different elements, which are not disclosed above even when not initially claimed in such combinations.
[0036] In addition, the words used in this specification to describe the invention and its various embodiments are to be understood not only in the sense of their commonly defined meanings, but also in the sense of any special definitions used in this specification, which may extend beyond the scope of the commonly defined meanings. Thus if an element can be understood in the context of this specification as including more than one meaning, than its use in the claims must be understood as being generic to all possible meanings supported by the specification and by the word itself.
[0037] The definitions of the words or elements of the following claims are, therefore, defined in the specification to include not only the combination of the elements which are literally set forth, but all equivalent structure, material or method steps for performing substantially the same function, in substantially the same way, to obtain substantially the same way to obtain substantially the same result. In this sense it is therefore contemplated that an equivalent substitution of two or more elements may be made for any one of the elements in the claims below or that a single element may be substituted for two or more elements in a claim.
[0038] Insubstantial changes from the claimed subject matter, now known or later devised, are expressly contemplated as being equivalently within the scope of the claims. Therefore, obvious substitutions now or later known to one with ordinary skill in the art are deemed to be within the scope of the defined elements.
[0039] 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 essentially incorporates the idea of the invention. | A surgical clamp for occluding a body conduit includes first and second jaws moveable relative to each other in a generally parallel relationship. A handle assembly is operable to move the jaws relative to each other between a space position and proximate position. The first jaw has an elongate configuration characterized by a length and a width. First portions of the first jaw have in cross section a first shape which remains generally constant in area along the first jaw, while second portions have in cross section a second shape which varies in area along the length of the first jaw. The resulting clamp has a low profile jaw design which dimensional-shaped cross section which provide increased stiffness and reduced flexibility. | 0 |
CROSS REFERENCE TO RELATED APPLICATION
The subject matter of this application is related to and comprises an improvement upon my invention as disclosed in the U.S Pat. No. 3,878,648, which issued on Apr. 22, 1975, for a Frame Concealed Operating Sash.
BACKGROUND OF THE INVENTION
The invention relates generally to window construction, but more particularly pertains to an exteriorly opening operating sash that is mounted in a manner that provides for uniformity of appearance and concealment of structure therebehind as when viewed from either the interior, and preferably, the exterior of the building in which it mounts.
In my previously identified United States patent therein is defined a window structure of the type that includes operating and fixing sashes that are mounted with a perimeter frame surrounding the opening in a building so as to form its window construction. The essence of that invention is to provide both a narrow line of sight for the combined sash and perimeter frame structure for the window when viewed either exteriorly or interiorly, and at the same time, furnish a zero line of sight due to the concealment of the narrow frame operating structure behind face flanges forming part of the fixed perimeter frame construction. The windows as shown and defined within this earlier patent were designed and constructed for use principally as interiorly opening windows that could be prefabricated and assembled for installation at a building site.
The present invention, recognizing some of the advantages of my earlier teachings with respect to the formation of window constructions from narrow frame structure that also maintain uniformity of appearance and the preferred zero line of sight, is herein concerned with the design of similar structure for use in perfecting an exteriorly opening window, or one which operates directly opposite from that which is set forth in my earlier patent. Obviously, structure must be redesigned from that which is shown in this prior art, since in the said art the various face flanges were formed integrally as part of the fixed structure of the stationary perimeter frame member of the composite sashes, and it was behind these face flanges that the operating components and the tubular like frame members forming the operating and fixed sash structures were concealed. To allow such window construction to be pivoted outwardly obviously entails a redesign of my earlier invention and that is what is to be defined hereinafter.
It is the principal object of this invention to provide a window structure for a building in which either a plurality of operating and/or fixed sashes may be confined within a window framework and in which the facade of the face flanges forming the exterior of the window structure completely conceals any of the operating structure arranged therebehind, even though the operating sashes of this invention are the type that open exteriorly of the building.
It is another object of this invention to provide operating sash window structure that includes narrow face flanges which conceal the operating hardware for the window in addition to the structural means forming the sash structure.
Another object of this invention is to provide an exteriorly opening operating sash that may be used in conjunction with a fixed sash but which provides means for furnishing a very narrow structural appearance to the entire window structure while at the same time insuring the desired zero line of sight of any of the components of the window structure maintained behind the window facade.
An additional object of this invention is to provide structure for a window construction that has a uniform appearance in width dimensions throughout its extent when viewed exteriorly of the building.
Another object of this invention is to provide structure for a window that has uniform width in its composite structure throughout its extent when viewed interiorly of the building structure.
Another object of this invention is to provide a structure for a window of the herein design that maintains sealed contact during closure.
These and other objects will become more apparent to those skilled in the art upon reviewing the summary of this invention, in addition to studying the description of its preferred embodiment in view of its drawings.
SUMMARY OF THE INVENTION
This invention contemplates the structure for a window assembly that may be prefabricated from various metals, usually extruded, then assembled and shipped, or either assembled at the job site, and then installed into the building structure as it is being erected. Particularly, and as previously emphasized, the invention is intended to provide structure for a window that maintains both the narrow profile for the structural components that are of uniform dimension throughout their extent, and yet maintains the preferred zero line of sight behind the structural facade of the window when viewed exteriorly, all of these advantages being attained from window structure incorporating exteriorly opening operating sash, or sashes, or combinations of operating and fixed sashes.
The window structure includes a perimeter frame, made up of mitered and joined frame members, which essentially form the jamb, sill and head portions for the stationary part of the window structure, and which surround the various operating and fixed sashes that are built into the design. Where a pair of operating and/or fixed sashes are incorporated into the window design, an intermediate frame of tubular like structure is designed for spanning the distance between fixed sides of the perimeter frame, whether it be between the sill and head portion, or the two side jamb portions, with the intermediate frame providing support for the overall window structure, in addition to cooperating with the various framing mechanisms that either secure the fixed sash in place, or provide a surface for maintaining sealing closure with a part of the operating sash when said sash is maintained in a closed position.
Essentially, the perimeter frame that forms the jamb, sill and head portions surrounding the operating sash, and thereby forming the operating sash opening therethrough, includes an integral projecting shoulder that cooperates with a face flange integrally formed with the tubular like structure and reglets forming the operating sash, with the cooperation between said shoulder structure and the face flanges of the operating sash providing sealing closure to the sash when maintained in its closed position, while additionally furnishing the desired zero line of sight of any of the structural components of the entire window structure that are maintained rearwardly thereof. In addition, the face flanges that are formed either in the window structure making up the fixed sash opening, or formed as the face flanges that extend outwardly in their integral connection to the structure of the operating sash, are designed having uniformity of width, and at a narrow profile, so that the entire window structure when viewed exteriorly presents uniformity of dimension and streamlined appearance to the overall window structure. The operating sashes formed into the window construction may be hingedly mounted to the perimeter frame so as to provide any variety of directional outward opening, such as either a bottom opening window, top opening window, or even a laterally opening window construction when opened. Such is preferable particularly in those jurisdications that for fire code purposes require that apertures in the building must be both quickly and conveniently opened outwardly, even against one onrush of occupants, such as may occur in an emergency situation as when a fire is encountered.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings, FIG. 1 provides an isometric view of an example of the window structure of this invention incorporating operating and fixed sashes;
FIG. 2 provides a front view of the window structure of this invention as shown in FIG. 1;
FIG. 3 provides a horizontal sectional view through a jamb portion of an operating sash as taken along the line 3--3 of FIG. 2;
FIG. 4 provides a vertical sectional view through the window structure taken along the line 4--4 of FIG. 2;
FIG. 5 provides an isometric view of an example of the window structure of this invention incorporating a pair of operating sashes;
FIG. 6 provides a front view of the window structure of this invention as shown in FIG. 5;
FIG. 7 provides a transverse sectional view of the window structure taken along the line 7--7 of FIG. 6; and,
FIG. 8 provides a vertical sectional view of the window structure taken along the line 8--8 of FIG. 6.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In the drawings, and in referring particularly to FIGS. 1 and 2, there is shown one aspect of the window structure 1 of this invention, which in this particular instance contains an operating sash 2 provided in its upward portion, with a fixed sash 3 being secured into the window structure therebelow. The window structure comprises a perimeter frame 4 that surrounds the periphery of the window, and which frame is comprises of jamb portions 5 and 6, a head portion 7, and a sill portion 8.
These portions are conveniently mitered and joined together at their ends by a series of corner blocks (not shown) as customarily used in the fabrication of structures of this type. Approximately at the midpoint of the perimeter frame is an intermediate frame 9 which spans the distance between the side jambs, being rigidly fastened thereto, so as to provide separation between the operating sash and fixed sash openings and to conveniently provide peripheral frame structure for mounting of these particular sashes.
As shown in FIG. 3, the construction of the various frame members making up the perimeter frame and operating sash frame, and the hardware structure pivotally mounting these two members together, are shown. As can be seen, the jamb member 5 is formed of a semi-tubular like structure, which includes a projecting shoulder portion 10 that has a slight rearward extension 11, while the backside of the member 5 includes a forward extension 12, which extensions cooperate to form the semi-tubular or channel like member that provide rigidity to the jamb portion of this perimeter frame, and into which the corner block, as aforesaid may be inserted to hold same frame together.
Obviously this member 5 could be constructed into the tubular shape to add rigidity to this jamb. The frontal portion of the shoulder 10 provides a surface formed so that it may mount a gasket 13, such as one made of neoprene, that may insert so as to provide a sealing surface for cooperating with the operating sash and maintain the same in sealed closure as desired.
The back of said jamb member 5 includes an inwardly extending member 14, in the nature of a rear flange, that is designed to align with the back side of the structure of the operating sash 2 to also maintain the same in sealed contact, as when the window is pivoted closed. Standard hinge structure, as at 15, is provided between the jamb portion 5 and the operating sash 2 so as to provide the focal point for pivoting of the window during its manipulation.
The operating sash 2 is formed of tubular like frame members 16 around its perimeter and includes forwardly thereof an integral reglet 17 for securing the window glaze 18 firmly in place, and a gasket 19 is arranged therein so as to provide sealed retention of the glaze firmly within the frame of the operating sash. Provided integrally across the front of the reglet, and extending outwardly therefrom, is a face flange 20 which is provided with sealing means, such as a contact surface or point 21, at its outer periphery and which can contact into closure with the gasket 13 of the fixed perimeter frame.
The backside of the tubular like member 16 of the operating sash frame 2 is provided with a slot 22 into which another gasket 23 may be inserted and maintained for sealed closure with the contact point or surface 2 provided at the outer edge of the rear flange 14.
As can be seen from the foregoing disclosure, and upon reviewing FIG. 3, the structural components and the hinge hardware of the operating sash are substantially concealed behind the face flange 20 of the window structure as said structure is viewed from the exterior of the building in which it is installed. The face flanges and rear flanges are of substantially narrow width, being somewhat less in width than the entire width from rear to front of the perimeter frame 4, as seen in its jamb portion 5, and thereby provide both a narrow profile and uniformity of appearance in the entire window structure as when viewed, as aforesaid. It may herein be stated that the jamb portion 6 of this perimeter frame, in addition to the proximate tubular like frame of the operating sash contiguous thereto, are a mirror image of the same components as are previously defined in the make up of the jamb portion 5 and the sash structure as just defined.
FIG. 4 discloses that the structure of the head portion 7 and sill portion 8 are substantially identical in construction to the structure of the jamb portions 5 and 6 as just previously described. The only exception is that where the perimeter frame, and in particular where its sill and jamb portions form the frame for the fixed sash 3 of the window structure, then a face flange, as at 25, extends inwardly from the extension 26 provided integrally projecting from the semi-tubular structure of the perimeter frame, as represented by its sill portion 8. For the purpose of maintaining uniformity of appearance of the entire window structure, regardless whether the sashes may both be of the operating type, or of the combined operating and fixed type sashes, the width of the face flanges 25 are substantially identical to the width of the face flanges 20 previously described as extending integrally around the front of the operating sash 2. Hence, uniformity of width and appearance is provided throughout the window structure as when viewed exteriorly, and since a similar type of rear flange 27 is provided to the backside of the sill portion 8, and which flange is rather identical in construction to the rear flange 14 as previously described, uniformity of appearance to the entire window structure is equally maintained upon the backside of the window structure when viewed from within. The head portion 7 is also provided with the shoulder portion 28, which mounts its gasket 29, so as to furnish a sealed closure when encountering the contact edge 30 formed outwardly of the face flange 31 of the operating sash 2. The operating sash 2, at these upper and lower locations within the window structure are also formed of tubular like members 32, which are equivalent to the tubular like member 16 previously described, and each includes the integral reglets 33 forwardly thereof which secure the gasket 19 for holding the glaze 18 in place. The face flange 31 extends along the top portion of the operating sash structure, and is identical in construction to the face flange 34 maintained along the bottom of the operating sash structure, with both of said face flanges being identical to the vertical face flanges 20 integrally formed to the side of the operating sash structure. The backside of the tubular like frames 32, of the operating sash 2, contain a retained gasket, as at 35, for cooperating with the rear flanges 36 and 37 for providing sealed contact for the operating sash at this location when it is maintained in closure and contacts the flange ends.
Provided spinning the distance across the perimeter frame 4 is the intermediate frame member 9, which also is constructed as a tubular like structure, or any form of reinforced structure, and which disposes a surface 38 to which a gasket 39 may be secured, and which may cooperate with a flange edge 40 of the face flange 34 for likewise maintaining sealed closure at this location for the operating sash. Since this intermediate frame 9 provides a seat for both the operating sash 2, as just previously defined, and the fixed sash 3, obviously it does not possess an upper integral face flange, bur rather, in its place is the surface 38 that cooperates with the face flange 34 provided upon the said operating sash. On the other hand, the intermediate frame 9 also includes the integral and inwardly extending face flange 41 which cooperates with the retainer 42, and the gasket 43, for securing the fixed glaze 44 in place. A similar type of retainer 45 cooperates with the gasket 46 and that face flange 25 for securing the lower edge of the glaze 44 rigidly and permanently in place. This particular style of structure has already been somewhat described in my said previous patent wherein a fixed sash, and its method of mounting, was detailed.
The window structure disclosed in FIGS. 5 and 6 comprises a perimeter frame 47 that mounts a pair of operating sashes 48 and 49, which in this particular design, are of the horizontal pivoting window design that open outwardly from their center. This perimeter frame is composed of similar style jamb portions 50 and 51, head portion 52, sill portion 53, and an intermediate vertically extending frame member 54. Obviously, while the intermediate frame 54 is herein shown and described as being vertically arranged within the perimeter frame structure, it could just as likely mount horizontally or transversely within the same so as to separate a pair of upper and lower operating sashes, or even operating and fixed sashes as previously defined with respect to the window structure of FIG. 1.
The detailed structure of the various components that make up the perimeter frame and the operating sashes of this invention are very similar in construction to the structure that has already been described with respect to the window of FIG. 1, wherein and as can be seen in FIG. 7, the jamb portions 50 and 51 are secured to the wall structure 55 of the building structure, while the head portion 52 and the sill portion 53 are likewise secured to similar contiguous wall structure. Each of the structures 50 through 53 are formed of semi-tubular like structure, or even tubular structure, usually of extruded metal stock, and include an inward extending shoulder 56 and 56a, each which supports a respective gasket 57 and 57a that cooperate with a contact edge 58 and 58c of the face flanges 59 and 59a of the various operating sashes. The back end of each of the portions 50 through 53 include an inwardly extending rear flange 60 through 60c that include a contact edge or surface 61 through 61c for cooperating with their respective gaskets 62, 62c, 62 d, and 62e provided at the backside of the structure of the operating sashes.
The intermediate frame member 54 is formed of tubular like material, which includes a pair of rear flanges 63 and 64, that extend inwardly of their sash openings, and are aligned for contacting with the gaskets 62a and 62b which are likewise secured to the rear edge of the frames of their respective operating sashes. Said intermediate frame 54 includes a forwardly disposed surface as at 65 that mounts a gasket 66, that is aligned for being contacted by the contact members 58a and 58b of the various face flanges 67 and 67a of the pair of operating sashes.
Each of the operating sashes 48 and 49 are formed of tubular like material, as at 68 through 68e, around their perimeter, having the gaskets 62 through 62e provided at their rearward edges, while the forward edges are integrally formed having reglets, as at 69 through 69e, formed around their circumference, with each window formed reglet cooperating with a gasket as at 70 and 70a, for supporting their respective glazes 71 and 72. The forward edges of the aforesaid reglets are formed having the face flanges 59 through 59c, and 67 and 67a, arranged around their perimeter, extending slightly outwardly thereof, with their contact points 58 through 58e being aligned for encountering the gaskets 57 through 57c, as when these operating sashes are secured into closure. Obviously, since the operating sashes described forming the window structure disclosed in FIGS. 5 and 6 are of the horizontally opening type, conventional hinge means may be provided at the upper and lower lateral positions between the head 52 and sill 53 and their proximate tubular like frames 68d and 68e forming the framework for the various operating sashes as defined.
In addition to the foregoing, convention latching means may be utilized for securing these windows firmly in place as when they are locked into closure.
Various modifications to the window structure shown herein and described may be considered by those skilled in the art upon reviewing this disclosure. The description herein provided is of the preferred embodiment, and is set forth for illustration purposes only. Any modifications made to these exteriorly opening sashes for a window structure having the defined uniform appearance and narrow profile, and which may occur to those skilled in the art upon reviewing the disclosure, such modifications as may fall within the spirit and scope of this invention as defined in the appended claims, are intended to be protected by any patent issuing hereon. | In a window construction of the type incorporating particularly operating sash or sashes, and in certain embodiments an operating sash in conjunction with a fixed sash, a perimeter frame surrounds the composite of sashes, and supports an intermediate frame that is arranged between each pair of adjacent sashes. The perimeter frame is constructed of semi-tubular like structure, and that portion of the perimeter frame surrounding the exteriorly opening operating sash includes a formed shoulder that cooperates to form a sealing contact with face flanges integrally connecting to the framework of the operating sash. Where a pair of operating sashes are arranged adjacently within the perimeter frame and intermediate frame, the formed shoulders contact the sash flanges when said sashes are closed, while the back of the sashes exposes a surface that retains a sealing contact with the proximate rear flanges of the perimeter frame when said sashes are maintained in closed position. | 4 |
BACKGROUND OF THE INVENTION
(a) Field of the Invention
The present invention relates to a fuel feeding apparatus for internal combustion engines which comprises an area type air flow rate measuring section in which the air flow is dependent on the displacement of an air flow rate detecting valve, and a fuel flow rate measuring and distributing section in which a variable orifice defined by a rotor and a stator determines the fuel flow rate proportional to the air flow rate, said apparatus being characterized in that the air-fuel ratio is compensated by the output signal from an exhaust gas sensor disposed in the exhaust pipe.
(b) Description of the Prior Art
Various types of such fuel feeding apparatus have already been invented. An example thereof is shown in FIG. 1. In FIG. 1, the numeral 1 designates a fuel flow rate measuring and distributing section and 2 designates an area type air flow rate measuring section. The measuring and distributing section 1 comprises a stator 3 and a rotor 4. The stator 3 has a fuel inlet 5 and fuel outlets 6. The inlet 5 is formed with an annular groove 7, while each outlet is formed with an orifice 8. The rotor 4 has a fuel inlet 9 which is in constant communication with said inlet 5 through said annular groove 7, and a triangular window 10 which opens to an outlet 8. The rotor 4 is rotated in synchronism with an engine 12 through a shaft 11 and is axially slid as the flow rate detecting valve 15 of the area type air flow rate measuring section 2 is moved, as will be later described in more detail, thereby changing the time during which the triangular window 10 opens to the orifice 8. (See FIG. 2)
The area type air flow rate measuring section 2 comprises a servo-valve mechanism 16 adapted to sense the pressure difference (P1-P2) across a flow rate detecting valve 15 disposed upstream of a throttle valve 14 placed in a suction pipe 13 and maintain said pressure difference at a fixed value and amplify the same, and a valve opening mechanism 17 adapted to control the pressure difference (P1-P2) across the flow rate detecting valve 15 by using a pressure Pn amplified by the servo-valve mechanism 16. The servo-valve mechanism 16 comprises a chamber a subjected to a pressure P1, a chamber b subjected to a pressure P2, said chambers a and b being separated from each other by a diaphragm 18, a chamber c maintained at the same pressure as the pressure P1 in the chamber a, a variable orifice 20 whose area of opening is varied by a ball valve 19 fixed to the diaphragm 18, and a chamber d at a pressure Pn which is varied by the orifice 20 within the range of the pressure difference (P1-P2) between the chamber c and an intermediate chamber 21 (which is disposed between the flow rate detecting valve 15 and the throttle valve 14). The numeral 22 designates a bimetal disposed in the chamber a for controlling the diaphragm 18 so that the air-fuel ratio will be reduced, i.e., the amount of fuel in the mixed gas will be increased during the warm-up of the engine, the arrangement being such that when a heater 24 is energized through a switch 23, the bimetal 22 will be bent upward to release the diaphragm. The numeral 25 designates a pressure difference setting spring disposed in the chamber c, and 26 designates a bellows containing a gas at a reference temperature and a reference pressure, the effective area of said bellows 26 being determined so that (the effective area of the bellows 26)×(the pressure of the reference gas)=(the effective area of the pressure difference setting diaphragm 18 of the servo-valve mechanism 16)×(the difference pressure at the reference temperature and pressure). In addition, the bellows 26 is used to ensure that the area of opening of the flow rate detecting valve 16 will be proportional to the weight flow rate of air, and it is unnecessary if said area of opening is to be proportional to the volume flow rate of air.
The valve opening mechanism 17 causes the pressure Pn in the servo-valve mechanism 16 to act on a bellows 31 to control the axial position of the shaft 32 of the flow rate detecting valve so that the pressure difference P1-P2 across the flow rate detecting valve 15 will have a certain fixed value. The shaft 32 of the flow rate detecting valve controls the axial position of the rotor 4 of the fuel flow rate measuring and distributing section 1 so that the time of communication of a fuel metering port defined by the orifice 8 and triangular window 10 will be proportional to the weight flow rate of air. The numeral 33 designates a fuel tank; 34 designates a fuel pump; and 35 designates a pressure regulator. The pressure regulator 35 is divided into chambers e and f. The chamber e has installed therein a difference pressure setting spring 37 and an adjusting screw 38 and is subjected to a negative pressure P4 existing in the vicinity of an injector 39 at the suction pipe 13, while the chamber f has installed therein a valve seat 40 fixed to the diaphragm 36 and a valve 41, said valve seat 40 and valve 41 constituting a variable valve. The chamber f communicates with the fuel pump 34 and with the inlet 5 of the fuel flow rate measuring and distributing section 1, while the valve 41 communicates with the fuel tank 33. Therefore, the diaphragm 36 is subjected to the suction pipe negative pressure P4 in the vicinity of the injector 39 and to the feed pressure P3 at which the fuel is fed to the measuring and distributing section 1, so that it detects the pressure difference P3-P4. If the pressure P4 changes, the diaphragm 36 will be bent upward to increase the area of opening between the valve seat 40 and the valve 41, thus increasing the amount of fuel flowing from the valve 41 back to the fuel tank 33. As a result, the feed pressure P3 is reduced, and when a predetermined pressure difference is reached, the diaphragm 36 will be balanced and come to rest. In brief, the pressure regulator 35 maintains the pressure difference P3-P4 across the fuel metering and distributing section 1 at a fixed value irrespective of variations in the suction pipe negative pressure P4, thereby ensuring that the time of communication between the orifice 8 and the triangular window 10 will be uniquely proportional to the flow rate of fuel.
Because of the arrangement described above, the time of communication of the orifice is proportional to the area of opening of the flow rate detecting valve 15, as described above. As a result, the fuel flow rate is proportional to the weight flow rate of air, so that the air-fuel ratio is maintained at a constant value.
SUMMARY OF THE INVENTION
The present invention realtes to a fuel feeding apparatus of the type in which the pressure difference across a throttle valve disposed in a suction pipe is maintained at a constant value by a servo-mechanism utilizing fluid pressure and the amount of air being sucked into an internal combustion engine is measured by the degree of opening of the throttle valve while the degree of opening of the throttle valve is caused to be uniquely associated with the amount of communication of a fuel metering gate disposed in a fuel feed passage, said apparatus being characterized by the provision of a control mechanism wherein a set value for a pressure regulating valve or pressure difference regulating valve which is adapted to maintain the pressure difference across said fuel metering gate is controlled by an on-off action brought about by a signal from an exhaust gas sensor disposed in an exhaust pipe, while the on-off signal is rectified and the basic servo-set value for said servo-mechanism is controlled so that the value of said on-off signal will attain a predetermined value, the time ratio of the on-off action provided by the signal from the exhaust gas sensor being maintained at a predetermined value, thereby making it possible to improve the responsivity and obtain a constant on/off time ratio, which improves the control accuracy. Further, since any desired air-fuel ratio can be obtained by changing the set value associated with the heater side, it is possible to meet cayalyst requirements.
According to the invention, a solenoid valve adapted to be actuated by an output from the exhaust gas sensor, and a hydraulic pressure regulator having a hydraulic cylinder disposed in parallel with a pressure-sensitive diaphragm and with a pressure difference setting spring for said solenoid valve, are disposed in the feed line of the fuel flow rate measuring and distributing section. The hydraulic pressure acting on the hydraulic cylinder is controlled by said solenoid valve to correct the set pressure for the hydraulic regulator and control the fuel flow rate. Therefore, the responsivity of the control action is improved and hence the exhaust gas control in the period of engine transition is improved.
According to the invention, the spring force acting on the pressure difference setting diaphragm of the servo-mechanism is controlled by changing the gas pressure in the cavity of the bellows or second diaphragm engaged with the pressure difference setting diaphragm. Further, said gas pressure is controlled by a signal from a combustion gas sensor, thus making it possible to achieve complete combustion in the internal combustion engine.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an explanatory view of a known fuel feeding apparatus for internal combustion engines;
FIGS. 2a and 2b are views showing the constructions of a rotor and a stator, respectively, in the fuel flow rate measuring and distributing section of the apparatus shown in FIG. 1;
FIG. 3 is an explanatory view of a fuel feeding apparatus according to the present invention;
FIG. 4 is an explanatory view of a control unit;
FIG. 5 is a graph showing the output characteristic of a sensor which detects the oxygen concentration in the exhaust gas;
FIG. 6 is a graph showing the relationship between the oxygen gas concentration in the exhaust gas and the set point for a switching unit;
FIG. 7 is a view showing a modification of the device for controlling the spring force on the pressure difference setting diaphragm of a servo-mechanism by a signal from a combustion gas sensor;
FIG. 8 is a view showing another modification of the device shown in FIG. 7;
FIG. 9 is a graph showing the relationship between the excess air factor λ after control and the force of the adjusting spring of a pressure regulator;
FIG. 10 is a graph showing the relationship between the fuel pressure Pf, excess air factor λ and the set spring pressure for the adjusting spring; and
FIG. 11 is an explanatory view of another embodiment of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In FIG. 3, the parts which are the same as those of the conventional apparatus shown in FIG. 1 are indicated by like reference numerals.
According to the present invention, an exhaust gas sensor 51 is provided in the exhaust manifold 50 of an engine 12 in order to detect the burning condition of the mixed gas. The output from the exhaust gas sensor 51 is processed by a control unit 52 to actuate a solenoid valve 53 disposed in a fuel feed line La and control the set pressure for a pressure regulator 54 while actuating a compensating element 55 which compensates the spring force acting on the diaphragm 18 of a servo-mechanism 16, thereby compensating the air-fuel ratio.
As shown in FIG. 4, the control unit 52 comprises a first input terminal 56 which receives an output from the exhaust gas sensor 51, a second terminal 57 which receives an input of predetermined value which is separately set, a first deviation detecting circuit 58 which compares the signals at the terminals 56 and 57, a switching circuit 59 which on-off-controls said solenoid valve 53 in fuel feed line La by a signal from said first deviation detecting circuit 58, a rectifiying circuit 60 which receives and rectifies a signal from said switching circuit 59, a second deviation detecting circuit 62 which makes a comparison between a signal rectified by the rectifying circuit 60 and a set value from a third terminal 61, and a control circuit 63 which controls the voltage to be applied to the compensating element 55 installed in the servo-mechanism 16 by a signal from the second deviation detecting circuit 62.
The solenoid valve 53 comprises a solenoid 64, a spool 65 adapted to be advanced and retracted within the solenoid 64, and communication ports 66, 67 and 68. The solenoid 64 is controlled by the output from the switching circuit 59 of the control curcuit 52. The communication port 66 has an orifice 82 connected to the feed lin La, the communication port 67 communicates with the communication port 70 of the pressure regulator 54 through an orifice 69, and the communication port 68 communicates with a fuel tank 33 through a drain pump 71.
On the side of the chamber g of the pressure regulator 54 divided by a pressure-sensitive diaphragm 72, a hydraulic cylinder 74 with a diaphragm 73 disposed in the middle is fixed to the pressure regulator 54, the chamber 75 above the diaphragm 73 being formed with said communication port 70. Further, the diaphragm 73 is connected to the pressure-sensitive diaphragm 72 through a connecting rod 76. The numeral 77 designates a pressure difference setting spring for the pressure-sensitive diaphragm 72. A chamber h below the pressure-sensitive diaphragm 72 is provided with a communication port 78 connected to the feed line La and a communication port 79 communicating with the fuel tank 33 through the drain pump 71. The communication port 79 cooperates with a valve 80 fixed to the pressure-sensitive diaphram 72 to define a clearance 81 to control the flow rate of fuel flowing back to the fuel tank 33.
When the air-fuel ratio changes with the change of the operating condition, it is detected by the exhaust gas sensor 51 disposed in the exhaust manifold 50. For example, when the air-fuel ratio is smaller than the theoretical air-fuel ratio, i.e., when the mixed gas is fuel-rich, the control unit 52 produces an output with the theorectical air-fuel ratio as the reference. This output signal actuates the solenoid valve 53. Thus, the solenoid 64 retracts the spool 65, i.e., it actuates the spool in the direction in which the spool is thereby opened. As a result, fuel is introduced from the feed line La into the communication port 66, with an increased amount of fuel flowing back to the fuel tank 33 from the orifice 82 via the communication port 68 and drain pump 71, while fuel is introduced from the orifice 69 into the communication port 67 and then into the communication port 70 of the pressure regulator 54, so that the liquid pressure acting on the diaphragm 73 of the pressure regulator 54 is reduced. This reduction of liquid pressure upwardly displaces the diaphragm 73, upwardly moving the pressure-sensitive diaphragm 72 through the connecting rod 76 against the setting force of the pressure difference setting spring 77. The upward movement of the pressure-sensitive diaphragm 72 increases the area of opening of the clearance 81 defined by the valve 80 and communication port 79. Ultimately, this reduces the resistance to the flow of fuel flowing from the feed line La successively through the communication port 78, the chamber h of the pressure regulator 54, the clearance 81, the communication port 79 and the drain pump 71 and back to the fuel tank 33. Therefore, the feed pressure P3 in the feed line La is reduced by an amount corresponding to the resistance to the return fuel flow and becomes P3'. In addition, the fuel flowing from the solenoid valve 53 back to the fuel tank 33 is constricted by the orifice 82 and is so small in amount that it has no effect on the feed pressure P3 in the feed line La. Consequently, the flow rate of fuel measured by the orifice 8 and triangular window 10 of the fuel flow rate measuring and distributing section 1 is reduced by an amount corresponding to P3-P3', so that the air-fuel ratio is increased to be corrected approximately to the theoretical air-fuel ratio.
The foregoing refers to the compensating operation where the air-fuel ratio is smaller than the theoretical air-fuel ratio, i.e., where the mixed gas is fuel-rich. However, when the air-fuel ratio is greater than the theoretical air-fuel ratio, i.e., when the mixed gas is fuel-lean, it will be corrected to the theortical air-fuel ratio in the reverse action by increasing the feed pressure P3 to reduce the air-fuel ratio.
Usually, when the exhaust gas is purified with a three-element catalyst 83, it is desirable to control the air-fuel ratio so that it is equal to the theoretical air-fuel ratio. That is, it is desirable that the excess air factor λ, defined as the ratio of the air-fuel ratio to the theoretical air-fuel ratio, be equal to 1. In this case, an oxygen gas sensor is suitable as the exhaust gas sensor. Further, it is known that the output from the oxygen gas sensor 51 for detecting the oxygen concentration in the exhaust gas will exhibit a characteristic which changes at the theoretical air-fuel ratio, or λ=1, like a step function, as shown in FIG. 5. The output from the exhaust gas sensor 51 is fed to the control unit 52 so that the latter may actuate the compensating element 55 which compensates the spring force acting on the pressure difference setting diaphragm 18 of the servo-mechanism 16.
FIG. 3 shows the use of a heater 84 as said compensating element 55, said heater 84 being installed in the bellows 26. If the basic setting level for the servo-mechanism 16 is set, for example, at λ=0.9 on the fuel-rich side, as shown in FIG. 6, then since the oxygen concentration in the exhaust gas is low, the control circuit 63 shown in FIG. 4 is turned on to energize the heater 84, so that the gas enclosed in the bellows 26 and its pressure are increased and hence the upward force acting on the diaphragm 18 is increased, upsetting the balance of the forces on said diaphragm 18, and the variable orifice 20 is thereby opened. Thereupon, the pressure Pn in the chamber D is increased, displacing the bellows 31 of the valve opening mechanism 17, so that the flow rate detecting valve 15 is displaced in the closing direction. The rotor 4 is then moved to the right as viewed in the figure. Therefore, the amount of fuel relative to the amount of suction air is reduced to shift the air-fuel ratio to the fuel-lean side. As a result, the oxygen concentration in the exhaust gas and hence λ are increased to the extent that the output from the exhaust gas sensor disappears, deenergizing the heater 84 at point a. Thereupon, the gas enclosed in the difference pressure setting bellows 26 contracts and the variable orifice 20 returns to the basic set level side, thereby increasing the amount of fuel relative to the amount of suction air. When the air-fuel ratio is reduced and the mixed gas is shifted to the fuel-rich side, the heater 84 is energized again at point b, shifting the mixed gas to the fuel-lean side by increasing the air-fuel ratio. Such on-off control of the heater by the control unit makes it possible to control the air-fuel ratio so that it is nearly equal to the theoretical air-fuel ratio, i.e., λ≈1.
In the system described above, if the relation Pdo·Sd =Pd·Sb is established where Sb is the area of the bellows, Pb is the absolute pressure of the gas enclosed in the bellows in the reference condition, and the Pd is the reference value of the pressure difference across the flow rate detecting valve 15, and Sd is the effective area of the pressure difference setting diaphragm 18 of the servo-valve mechanism 16 then with no current flowing through the heater in the bellows it follows that γ×(P1-P2)=constant where γ is the density of the suction air, and hence the degree of opening of the flow rate detecting valve is proportional to the weight flow rate. Therefore, it follows that the basic set level of the air-fuel ratio is maintained constant irrespective of atmospheric pressure (altitude) and the temperature of the suction air.
FIG. 7 shows another embodiment of a servo-mechanism 16, wherein two bellows 85 and 86 are provided. A gas in the reference condition is enclosed in a space between the outer and inner bellows 86 and 86 so as to compensate for variations in the density of the suction air, and the pressure of the gas in the inner bellows 86 is made variable by means of a piston 87, cylinder 88 and solenoid 89 for the purpose of compensation. Thus, when the control unit 52 produces an on-signal, the solenoid 89 is energized to attract a magnetic plate 90 provided on the lower end of the piston 87 against the force of a spring 91. Therefore, the gas in the cylinder is forced out into the pressure difference setting bellows 18 to increase the pressure in said bellows. This results in opening the variable orifice 20, increasing the air-fuel ratio, i.e., shifting the mixed gas to the fuel-lean side. In addition, the numeral 92 designates a choke disposed at the open end of the cylinder 88 and serves to prevent the gas in the bellows 86 from being forced out suddenly. When the signal from the control unit 52 is cut off, the piston 87 is returned to its original position by the force of a spring 91 and the pressure in the bellows 86 resumes its original value, reducing the air-fuel ratio, i.e., shifting the mixed gas to the fuel-rich side.
FIG. 8 shows another modification of the servo-mechanism, wherein a second diaphragm 93 and a return spring 94 are provided above the diaphragm of the servo-mechanism, the inner side of said diaphragm 93 being connected to a vacuum tank 97 through a line 95 and a choke 96. The vacuum tank 97 communicates with the downstream side of the throttle valve 14 of the suction pipe of the engine through a check valve 98. The line 95 is open to atmospheric pressure P1 through a variable choke or a valve 99. The negative pressure in the suction pipe is collected in the vacuum tank 97 and is on-off controlled by an exhaust gas sensor attached to the exhaust pipe, as in the embodiment described above, to change the pressure in the bellows 93, thereby compensating the air-fuel ratio.
The foregoing description refers to a method of controlling the pressure in the bellows provided in the servo-mechanism by a signal from the exhaust gas sensor. However, by making said pressure variable according to the degree of opening of the throttle valve, variations in the negative pressure in the suction pipe, the temperature at the start of the engine, etc., it is possible to compensate the amount of fuel to increase the same at the time of idling, at the time of running at full throttle, at the start of the engine, etc. Further, it goes without saying that the present invention is not limited to the embodiments described above but is applicable to a case where a mixed gas of fuel and air is fed to a furnace.
Even if the set pressure of the pressure difference setting spring 77 of the pressure regulator 54 is within the range of control, there is the possibility of the mixed gas being deviated to the fuel-rich or fuel-lean side depending upon the running conditions of the engine. It has been ascertained that if the force of the spring 77 is set at the fuel-rich side, the air-fuel ratio after control is deviated to the reduced side, as shown in FIG. 9.
FIG. 10 is a graph showing the relationship between fuel pressure Pf, the excess air factor λ (where λ=air-fuel ratio/theoretical air-fuel ratio), and the set pressure of the pressure difference setting spring. In the graph, τ 1 is the time during which the solenoid valve 53 is on and τ 2 is the time during which it is off. In order to control the excess air factor λ so that it is equal to 1, it is most preferable to maintain the ratio of τ 1 to τ 2 constant throughout the operating range.
The output from the exhaust gas sensor 51 is delivered as an on-off signal by the switching circuit 59, as described above. This on-off signal is fed to the rectifying circuit 60 in such a manner that when the switching circuit 59 is on, it is 1 and when said circuit is off, it is 0, said signal being rectified therein and then fed to the second deviation detecting circuit 62. For example, in the case of FIG. 10a, and therefore the output from the rectifiying circuit 60 is less than 0.5. At the same time, a set value such that τ 1 =τ 2 , i.e., 0.5, is fed from the terminal 61, and a signal will be kept delivered until the result of comparison between the two values becomes zero. In this case, the voltage applied to the heater 84 of the servo-mechanism 16 is controlled by the control circuit 63 in a direction in which it is thereby reduced so as to lower the temperature in the bellows, thereby controlling the basic set value for the servo-mechanism 16 in a direction to reduce the air-fuel ratio. In the case of FIG. 10b also, the output from the rectifiying circuit is between 0.5 and 1, and the air-fuel ratio is controlled to be shifted toward the increasing side until the difference between the output and the comparison set value 0.5 is zero, thereby achieving τ 1 =τ 2 .
FIG. 11 shows another embodiment of the invention, wherein a fuel metering and distributing mechanism 100 is designed to continuously meter fuel in connection with the amount of suction air. More particularly, a fuel metering gate is constituted by an annular slit 102 formed in a spool 101 and substantially triangular windows 104 formed in a sleeve 103. The numeral 105 designates a pressure difference control unit whereby the pressure drop at the fuel metering gate 102, 104 is maintained constant. A servo-mechanism 106 uses the fuel pressure as the control pressure and the output acts on the upper surface of the spool 101. A pipe 108 which connects the higher pressure chamber 107 of the pressure difference control unit 105 to the fuel source pressure is provided with a solenoid valve 109 and a choke 110, and a pipe 111 which bypasses the solenoid valve is provided with a choke 112. The numeral 113 designates a choke provided in a return pipe 114.
The output from an exhaust gas sensor 115 actuates a control unit 116 to on-off control the solenoid valve 109 to control the pressure difference between the higher pressure chamber 107 and a lower chamber 117 below the spool 101, thereby controlling the flow rate of fuel flowing through the fuel metering gate 102, 104. A heater 118 is also controlled so that τ 1 =τ 2 . In addition, in the figure, the numeral 119 designates a suction pipe; 120 designates an air flow rate detecting valve; 121 designates a connecting rod; 122 designates a pressure difference setting diaphragm; 123 designates a variable orifice interlocked to the pressure difference setting diaphragm; 124 designates a spring for setting a servo basic set value; 125 designates a bellows; 126 designates a pressure regulator whereby the difference (P1-Pi) between the negative suction pressure and the supply source pressure is maintained at a predetermined value; and 127 designates a fuel pump.
While specific embodiments of the invention have been described in detail with reference to the accompanying drawings, it is to be understood that the invention is not limited thereto and that various changes and modifications may be made by those skilled in the art without departing from the spirit and scope of the invention. | A fuel feeding apparatus for internal combustion engines comprises an area type air flow rate measuring section in which the air flow rate is dependent on the displacement of an air flow rate detecting valve, and a fuel flow rate measuring and distributing section in which a variable orifice defined by a rotor and a stator determines the fuel flow rate proportional to the air flow rate. This apparatus is characterized by the provision of an exhaust gas sensor disposed in the exhaust pipe for the detection of the oxygen concentration of the exhaust gas in order to achieve the complete combustion of fuel in the internal combustion engine, the output signal from the exhaust gas sensor being used to compensate the fuel feeding pressure and a spring force which acts on the pressure difference setting diaphragm of a servo-mechanism. | 5 |
This application is a continuation-in-part of U.S. Ser. No. 07/315,501, filed March 1, 1989, the disclosure of which is incorporated by reference herein.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention pertains to improved extruded and molded articles, to films, bottles, and the like with improved impact strength and reduced oxygen permeability as a result of the incorporation of a compatibilized barrier resin into such articles, and to methods of preparing such articles.
2. Description of Related Art
The polyolefins combine advantageous properties both technically and commercially. Polypropylene, for example, exhibits greater hardness and stiffness than polyethylene, lower brittleness than standard polystyrene, outstanding resistance to hot water and to chemicals, and very good electrical properties. Thus, the polyolefins and their copolymers have a wide range of applications in the form of containers, moldings, profiles, tubes, films, fibrillated filaments and textile fibers.
Formed polyolefin articles may be prepared by injection or blow-molding. In particular, stretch blowmolding is a mass production process for plastic bottles replacing the glass variety. These are used for oil, wine, spirits, milk, still and CO 2 -containing mineral water, soft drinks and beer. Although the polyolefins possess many desirable properties, as enumerated above, in the particular applications of containers and packaging films, it is desirable to reduce the gas permeability below that normally exhibited by polyolefin films and bottles.
Typically, an extruded film or blown bottle will be comprised of several layers of different polymers, arranged to exploit desirable properties and compensate for detrimental properties. For example, polypropylene offers structural integrity, but is permeable to many gases. A layer of a gas barrier resin, such as a nitrile barrier resin, will reduce the permeability to acceptable levels, even though the barrier resin itself may have undesirable properties, such as sensitivity to liquids. The barrier resin may be sandwiched between layers of the structural polyolefin to isolate the resin, while obtaining the advantages offered by the barrier. In particular, copolymers of ethylene with vinyl alcohol (EVOH) are used in the co-extrusion of packaging materials on account of the outstanding barrier properties against oxygen, nitrogen, carbon dioxide and fragrances imparted by the EVOH. Other polymers, such as poly(vinylidene chloride) (PVDC) may be used as the barrier resin. The selection of barrier resin is well within the purview of the skilled artisan and is not limited to EVOH and PVDC.
One means for the preparation of such desirable packaging materials, such as films and bottles, is the co-extrusion of an outer layer of polyolefin, a layer of barrier resin, and an inner layer of polyolefin.
However, the adhesion between the polyolefin and barrier layers is generally considered to be inadequate for most uses. Therefore, it is necessary to use an adhesive or tie layer between the polyolefin and the barrier layers in order to ensure sufficient mechanical strength to prevent delamination. Typical adhesive materials are copolymers of ethylene, such as Plexar (Quantum Chemical, USI Division).
A representative five-layer bottle may then have an outer polypropylene layer, an adhesive layer, an EVOH barrier layer, a second adhesive layer, and an internal polypropylene layer. Typically, the percentage of adhesive will be about 10% by thickness. A representative construction is approximately 14 mil polypropylene, 1.5 mil adhesive, 4 mil EVOH, 1.5 mil adhesive, and 14 mil polypropylene.
In extrusion blow-molding of bottles of this type, excess material must usually be removed from the finished product. This "scrap" will contain polypropylene, EVOH, and adhesive. For practical purposes, it is desirable to co-extrude this scrap layer with virgin polypropylene, adhesive, and barrier resin forming a six-layer container in which the scrap layer is sandwiched between the outer polypropylene layer and the first tie layer. In this way, the losses attributable to scrap are significantly reduced. This co-extrusion, however, often leads to significant problems with delamination and product quality.
Since it is a critical element of these constructions to have the barrier layer, it is also important that the barrier layer be one which is state-of-the-art in terms of its properties. Although EVOH is a widely used and highly regarded material, it suffers from the deficiency of being susceptible to water. The presence of the polypropylene protects it from water. However, in the construction of these bottles and films, it is still necessary to use the adhesive. The adhesive material adds increased cost and raises significant questions of processibility. It, therefore, is desirable to identify additional adhesive materials which will provide a better balance of properties than that currently available at improved processing efficiencies.
SUMMARY OF THE INVENTION
This invention provides an improved adhesive layer for multi-layer films and bottles, the adhesive layer being a graft copolymer of a polyolefin backbone with a methyl methacrylate graft. In addition, it has been discovered that the graft copolymer sufficiently improves the compatibility between barrier resins and polyolefins to permit the production of monolithic or single layer bottles comprised of a blend of those three components. The resultant products have improved physical properties while retaining acceptable permeability to gases.
DETAILED DESCRIPTION OF THE INVENTION
The graft copolymer which serves as the adhesive or compatibilizing resin for this invention is disclosed in U.S. Ser. No. 07/315,501, filed Mar. 1, 1989, now U.S. Pat. No. 4,957,974, of common ownership with this application. The disclosure of the aforementioned application is incorporated by reference herein.
The graft polymer is derived from at least about 80% of a monomer of a methacrylic ester of the formula CH 2 ═C(CH 3 )COOR, where R may be alkyl, aryl, substituted or unsubstituted, and less than 20% based on the total monomer weight, of an acrylic or styrenic monomer copolymerizable with the methacrylic ester. This is accomplished by adding the methacrylate monomers to a solution of the polyolefin together with an initiator which generates a constant, low radical concentration, or radical "flux", at the solution temperature. These radicals initiate polymerization of the monomer and cause formation of a covalent bond with the trunk.
The molecular weight of the polyolefin polymer which forms the trunk of the graft copolymer should be high enough to give a large amount of nonpolar polymer when grafted, but low enough so that most of the graft copolymer has one acrylic polymer chain grafted to each polyolefin trunk chain. The trunk may have a molecular weight between about 50,000 and 1,000,000. The trunk may also have a molecular weight of about 100,000 to 400,000. A polyolefin trunk having a molecular weight of about 200,000-800,000 Mw is especially preferred, but polyolefins having a molecular weight of about 50,000-200,000 can be used with some beneficial effect.
The preferred monomer is methyl methacrylate. As much as 100% of this, or of the other 2 to 4 carbon alkyl methacrylates, can be used. Up to 20% of high alkyl, such as dodecyl and the like, aryl, such as phenyl and the like, alkaryl, and such as benzyl and the like, and/or cycloalkyl, such as cyclohexyl and the like, methacrylates can be used. In addition, up to 20% (preferably less than 10%) of the following monomers can be incorporated with the methacrylate esters which form the major portion of the monomer: methacrylic acid, methacrylamide, hydroxyethyl methacrylate, hydroxypropyl methacrylate, alkoxyalkyl methacrylates, such as ethoxyethyl methacrylate and the like, alkylthioalkyl methacrylates, such as ethylthioethyl methacrylate and the like, methacrylamide, t-butylaminoethyl methacrylate, dimethylaminoethyl methacrylate, dimethylaminopropyl methacrylamide, glycidyl methacrylate, methyacryloxy propyltriethoxysilane, acrylate monomers (such as ethyl acrylate, butyl acrylate and the like), styrene, acrylonitrile, acrylamide, acrylic acid, acryloxypropionic acid, vinyl pyridine, and N-vinylpyrrolidone. In addition, as much as 5% of maleic anhydride or itaconic acid may be used. It is important that the chain transfer of the polymerizing chains to its own polymer is minimal relative to transfer with the polyolefin chains for the efficient production of homogenous non-gelled graft polymer in good yield.
The molecular weight of the acrylic graft was measured by the weight average molecular weight of the ungrafted co-prepared acrylic polymer may be about 20,000 to 200,000. The preferred range is 30,000 to 150,000.
The process of graft polymerizing the monomer leads to the production of ungrafted and grafted material. The amount of grafted material is in the range of 5% to 50% of the total acrylic polymer of copolymer produced. The graft copolymer is prepared in a process that polymerizes the monomer in the presence of the non-polar polyolefin. The process is conducted in a solvent which swells or dissolves the non-polar polymer. The solvent is also one that has no or low chain transfer ability. Examples include non-branched and branched aliphatic hydrocarbons, chlorobenzene, benzene, t-butylbenzene, anisole, cyclohexane, naphthas, and dibutyl ether. Preferably, the solvent is easy to remove by extrusion devolatilization, and therefore has a boiling point below 200° C., preferably below about 150° C. To avoid excessive pressure, a boiling point above about 100° C. is also preferred.
The final solids content (which includes polyolefin and acrylic polymer) depends on the viscosity and the ability to mix well. The practical limits are 20% to 70% but the solids content can be as high as is consistent with good mixing for economy. Preferably, the solids content falls in the range of about 35% to about 60%.
A gradual addition or multicharge addition of the monomer is preferred. Optionally, the monomer charge need not be the same throughout, for example, the last 0-20% may contain all of the monomer used in minor amount to concentrate that monomer in one portion of the polymer.
The temperature during the polymerization can be in the range 110° to 200° C., but the preferred range is 130° to 175° C. Especially preferred is 145° C. to 160° C. The pressure can be atmospheric to superatmospheric, or as high as 2100 kPa or whatever is necessary to keep the reaction mixture in the liquid phase at the polymerization temperature.
The unreacted monomer concentration should be kept low during the reaction. This is controlled by balancing the radical flux and the monomer feed conditions.
This application teaches the preparation of a variety of graft copolymers of polyolefins, in particular polypropylene, with methacrylate side chains. The use of this copolymer in a variety of resin systems has been seen to provide vastly improved compatibility, as evidenced by reduced domain sizes in polymeric blends. This application discloses and claims a significant advance in the film- and bottle-making art based upon the use of this novel copolymer as a compatibilizer for known resins.
EXAMPLE 1
Preparation of Acrylic/Polypropylene Graft Copolymer Compatibilizer
A polypropylene-acrylic graft copolymer was made by polymerizing a 5% ethyl acrylate-95% methyl methacrylate monomer mixture in the presence of polypropylene (weight ratio of polypropylene:monomer =0.67:1). Radicals were generated from di-t-butyl peroxide at the rate of 0.000070 moles/liter/minute (radical flux). Monomer and initiator were fed over 120 minutes and the theoretical (100% conversion) solids at the end of the reaction is 50%.
A 100-gallon reactor equipped with a pitched blade turbine agitator was charged with 190 lb. of Isopar E (a mixed aliphatic hydrocarbon solvent) and 76 lb. of polypropylene (Himont 6523, Himont, Inc., Wilmington, Del.). This mix was deoxygenated by applying vacuum to degas, followed by pressurizing with nitrogen to atmospheric pressure for three cycles. Finally, the mix was pressured to 15 psig with nitrogen and heated to 150° C. over 2 hours. A pressure of 35 psig was maintained while the batch was held at 150° C. for 3 hours. Two solutions were added over a 15-minute period. The first consisted of 59 g of di-t-butyl peroxide in 841 g of Isopar E. The second consisted of 0.32 kg of ethyl acrylate and 6.14 kg of methyl methacrylate. An additional 103 g of di-t-butyl peroxide and 1479 g of Isopar E were added over 105 minutes. At the same time, 2.26 kg of ethyl acrylate and 43.0 kg of methyl methacrylate were added over 105 minutes. The reaction exotherm increased the temperature to about 160° C. After the feed was complete, 11 lb. of Isopar E was fed into the reaction mixture.
The reaction mixture was held in the reaction kettle for an additional 30 minutes. It was then transferred to a second kettle, which was also under pressure at 150° C. During the transfer, a solution of 80 g of di-t-dodecyl disulfide in 320 g of Isopar E was added to the second kettle. Also during this transfer, three 10 lb. batches of Isopar E were fed into the reaction kettle. The material in this second kettle was fed to a 0.8 inch twin screw extruder, where devolatilization occurred.
During the devolatilization, the next batch was prepared in a reaction kettle. It was transferred to the extruder feed kettle while extrusion continued. In this way, several batches were made in a "semi-batch" matter, batch-wise in the reactor with continuous feed to the extruder.
Three samples of this material isolated at different times during the extrusion were blended with Himont 6523 polypropylene in a ratio of 4:96, pressed and tested for sag as described in U.S. Ser. No. 07/315,501. All three gave properties within the range of that expected for acceptable material.
A second batch of graft copolymer was prepared in a similar manner, except that the radical flux was 0.000050 (42 g of di-t-butyl peroxide plus 858 g of Isopar E in first feed; 73 g of di-t-butyl peroxide and 1502 g of Isopar E in second feed). Measurements of properties on this batch were also within the expected ranges.
The graft copolymer (GCP) used for the experiments described in the following examples was prepared by blending pellets from thirteen batches prepared in the first run and one batch of material prepared in the second run.
EXAMPLE 2
Preparation of Melt Blends of Polypropylene, EVOH, and Graft Copolymer(GCP)
Polypropylene, EVOH and the graft copolymer of Example 1 were compounded in an intermeshing, co-rotating twin screw extruder (Baker-Perkins, MPC/V 30) with an L/D of 10:1. The compounder was run at 200 rpm with a melt temperature of 205°-225° C. The melt was fed directly to a 38 mm single screw pelletizing extruder with an L/D of 8:1. The melt temperature in the transition zone between the compounding and the pelletizing extruder was 200°-215° C. The melt was stranded through a die, cooled in a water bath, and chopped into pellets. Visual observation indicated that the materials containing graft copolymer were fully compatible. These pellets were then dried and injection molded on a reciprocating screw injection molding machine (New Britain Model 75) into test specimens.
ASTM test methods were used to test the impact strength and tensile properties of the injection-molded parts. The results are summarized in Table 1.
EXAMPLE 3
Preparation of Films from Polypropylene/EVOH/GCP Blends
Five mil (0.13 mm) films were pressed for determination of permeability. The pellets that had been compounded as described in Example 2 were milled on a 3 inch by 7 inch electric mill at 205° C. for 3 minutes. The hot stock was then placed between preheated plates and pressed at 205° C. in a 100-ton Farrel press for 3 minutes at 2 tons followed by 2 minutes at 20 tons. The plates were transferred to a cool press for 1 minute of cooling at 2 tons pressure.
Oxygen permeation values were determined using a Mocon Ox-Tran 1000 tester (Modern Controls, Inc., Brooklyn Center, Minn.). The films for testing were prepared as 110 mm squares sealed into the unit and swept with nitrogen on both sides to determine a sample baseline and allow the film to equilibrate with nitrogen.
Pure oxygen at 1 atmosphere pressure was then swept over one face of the film for the duration of the test. The nitrogen swept over the opposite face of the film contained 1-2% hydrogen; this gas mixture was conducted from the test chamber through a Coulox nickel cadmium fuel cell detector, where any oxygen present burnt an equivalent amount of the excess hydrogen to generate an electric current proportionate to the amount of oxygen. This current, automatically corrected for the sample baseline, was continuously recorded and used to calculate the oxygen permeability value of the sample.
Test conditions during both equilibration and oxygen testing were 23° C. and 0% relative humidity.
The permeability data are reported in Table 1 in cc.cm/(sq.cm.cm.Hg.sec)xE(*12), where cc is cubic centimeters of oxygen, cm is film thickness in centimeters, sq cm is area of film in square centimeters, cm Hg is pressure in cm of Hg, sec is time in seconds, and E(*12) is 10 to the 12th power. The addition of 5-15% of the graft copolymer compatibilizer to binary compositions of EVOH and polypropylene improves the compatibility of the polar EVOH and the non-polar olefinic polypropylene.
The first three entries in Table 1 indicate that the compatibilizing copolymer does not negatively affect the permeability of EVOH films. Comparison of tests 4 and 5 indicates that the addition of approximately 5% of the GCP compatibilizer almost doubles the unnotched Izod impact strength, without affecting the permeability, and further increases the maximum stress, break strain, and tensile modulus.
When polypropylene is the majority component, it can be seen from test 7 that the oxygen permeability is rather high. The addition of the GCP at approximately in test 8 reduces the permeability by 33% while enhancing the physical properties. Even with the very high percentages of polypropylene in tests 10, 11 and 12, it can be seen that the presence of the compatibilizing additive improves the physical properties.
EXAMPLE 4
Preparation of a Co-extruded Five-layer Bottle Using the Compatibilizing Additive
A five-layer bottle was extruded through five separate Battenfeld Fischer extruders. Each extruder is independently controlled. Two molds for continuous extrusion of the parison were present. The materials used were polypropylene (Fortilene 41X11, Soltex), a layer of Plexar 460 adhesive (Quantum Chemical, USI Division), a barrier layer of EVOH (EVAL SC-F101, Eval Corporation of America), a second Plexar adhesive layer, and a final inner polypropylene (Fortilene 41X11) layer.
The polypropylene was extruded at a temperature between 190° and 200° C. The EVOH was extruded at a temperature between 205° and 210° C. In the first trials, Plexar 460 was used as the adhesive and was maintained at a temperature between 200° and 220° C.
An acceptable five-layer bottle was produced in these experiments.
The graft copolymeric compatibilizer(GCP) of Example 1 was substituted for both layers of Plexar 460 and it was determined that a GCP melt temperature of only 172° C. was needed to extrude coherent bottles which would withstand delamination using this new combination.
EXAMPLE 5
Preparation of a Monolithic Bottle from a Blend of Polypropylene, EVOH, and GCP Compatibilizer
A monolithic, single-layer bottle was prepared by extrusion blow-molding at about 200° C. of a blend of polypropylene, EVOH, and the compatibilizing additive of Example 1. The actual material used for this experiment was reground scrap from Example 4. Although this bottle was hazier than the traditional layered construction described previously, it was uniform in appearance and also did not have delamination problems. It is expected that this monolithic bottle should be useful in many applications in which permeability, strength, and optical clarity are desired to be between those of polypropylene and a multi-layered barrier construction.
TABLE 1__________________________________________________________________________PHYSICAL PROPERTIES OF EVOH/POLYPROPYLENE/GRAFT COPOLYMER BLENDS Maximum Tensile Break Unnotched EVOH/PP/GCP Stress Modulus Strain Izod OxygenNO. (%) (Kpsi) (Kpsi) (%) (ft-lb) Permeability__________________________________________________________________________1 100/0/0 8.6 479 114 -- 0.052 95/0/5 8.5 466 99 -- 0.083 87/0/13 8.1 454 11 -- 0.054 70/30/0 5.9 380 6 6.9 0.095 67/29/5 6.8 394 16 13.0 0.106 61/26/13 6.8 387 8 6.7 0.127 45/55/0 4.9 324 4 4.8 17.508 43/52/5 5.8 334 7 6.5 11.709 39/48/13 5.9 337 8 5.7 --10 20/80/0 4.8 279 10 4.8 14.9111 19/76/5 5.2 296 29 7.4 14.9712 17/70/13 5.4 306 12 8.5 13.8413 0/100/0 4.6 224 100 20.0 97.5014 0/95/5 4.8 248 100 20.0 --15 0/87/13 4.9 262 100 21.0 --__________________________________________________________________________
While the invention has been described with reference to specific examples and applications, other modifications and used for the invention will be apparent to those skilled in the art without departing from the spirit and scope of the invention defined in the following claims. | This invention provides an improved adhesive layer for multi-layer films and bottles, the adhesive layer being a graft copolymer of a polyolefin backbone with a methyl methacrylate graft. The graft copolymer sufficiently improves the compatibility between barrier resins and polyolefins to permit the production of monolithic or single layer bottles comprised of a blend of those three components. The resultant products have improved physical properties while retaining acceptable permeability to gases. | 8 |
FIELD OF THE INVENTION
The present invention relates to a method for the interconversion of enantiomers of acyclic 1,2-dihydroxy-3-alkenes. In addition, this methodology can convert acyclic 1,2-di-hydroxy-3-alkenes to the antipodal 1-hydroxy-2-alkoxy-3-alkenes. The resulting products are useful chemical intermediates that may be employed in the synthesis of many enantiomerically enriched compounds including pharmaceuticals and agricultural chemicals.
BACKGROUND OF THE INVENTION
There are many different methods that may be used to resolve racemic compounds. The use of enzymes derived from biological systems (for example, from a microorganism or an animal organ) have been particularly useful in the resolution of racemic compounds to form substantially optically pure (enantiomerically enriched) compounds.
In biocatalytic resolution systems, a chiral compound composed of two enantiomers is used as the substrate for the enzyme. The enzyme recognizes and favors only one of the enantiomers as the substrate for the enzymatic reaction. The stereoselectivity of the enzyme optimally affords a product mixture having 50% conversion to a single enantiomer product and 50% recovered substrate of opposite configuration (commonly referred to as an "antipode"). The success of a resolution procedure is determined by the optical purities obtained.
For an enzymatic kinetic resolution, the optical purities of the product and recovered substrate define the degree of enantioselectivity of the reaction and can be expressed as the "E" value. The "E" value is a directly proportional measurement of the R to S reactivity rate ratio, with higher optical purities for product and recovered substrate affording higher "E" values. Because the "E" value is independent of conversion, it is particularly useful in evaluating kinetic resolutions where optical purities can change depending on the extent of reaction. (Chen, C. S., et al., J. Am. Chem. Soc., 1982, 104, p. 7249.)
For present purposes, "substantially optically pure compounds" are enantiomerically enriched compounds defined as having an enantiomeric excess ("ee") value of greater than about 80%±2%. Enantiomeric excess ("ee") is the absolute value of % R minus % S and is used interchangeably with optical purity.
One typical consequence of a biocatalytic resolution process is the 50% maximum yield of each enantiomer. This limitation is particularly problematic if one enantiomer is more useful than its antipode. Frequently, an unwanted antipode is considered a "waste" material.
As with any product mixture resulting from a biocatalytic resolution system, interconversion of the unwanted enantiomer from the product mixture to the desired enantiomer (or at the very least racemization for recycling purposes) would be highly desirable to maximize yield and minimize cost of a useful product. It would be especially useful to develop a method of interconversion having high stereoselectivity to convert one enantiomer to the substantially optically pure antipodal product.
An example of a biocatalytic resolution process in which the interconversion process would be useful, for example, is with preparations involving 3-butene-1,2-diol (shown as structures 1 and 2 below, hereinafter referred to as "BDO"). ##STR1## As BDO is an especially useful chiral synthon, interconversion of the R- and S- BDO enantiomers, shown above as structures 1 and 2, would greatly enhance the versatility and utility of the biocatalytic preparation. The interconversion of BDO must rely in some manner on an inversion of configuration at the allylic carbon of a BDO derivative, most efficiently the corresponding epoxide, epoxybutadiene ("EpB" which may be readily prepared from BDO, or various derivatives, without loss of optical purity). Typically, inversion of configuration is approached using a concerted S N 2 (nucleophilic) process rather than an S N 1 process since S N 1 (ionizing) conditions normally lead to racemization, especially with allylic electrophiles (such as EpB) which afford stabilized carbocations. The allylic nature of EpB, however, presents complications for the inversion processes because three of the four carbons of EpB have significant electrophilic reactivity. Thus, a useful S N 2 interconversion process for EpB must be both highly stereoselective for inversion and yet regioselective for the chiral (allylic) center.
It is well known that more basic reaction conditions favor S N 2 processes while S N 1 reactions are favored at lower pH. (Lowry, T. H. and Richardson, K. S., "Mechanism and Theory in Organic Chemistry," Harper and Row Publishers, New York; 1981, pp.323-330.) The simplest S N 2 method with a potential for stereoselective inversion of EpB to form BDO is reacting the epoxide with hydroxide ion. However, it has been found that a similar nucleophilic opening of the epoxide of EpB with methoxide under basic conditions proceeds with high regioselectivity for the undesired primary epoxide terminus, thus encouraging retention of configuration. (Parker, R. E.; Isaacs, N. S., Chem. Rev. 1975, p. 737 and Smith, J. G., Synthesis, 1984, p. 629.) Indeed, reaction of S-EpB with sodium hydroxide affords BDO of only 30% ee, indicating significant reactivity at both epoxide carbons.
Although EpB can be opened under neutral or acidic conditions, it is known that as the reaction media becomes more acidic and ionizing, S N 1 processes (initial ionization) are favored. An S N 1 reaction would be expected to result in poor stereoselectivity, because once the epoxide opens to the corresponding stabilized allylic carbocation, the epoxide would be expected to rapidly and largely racemize. (Lowry, T. H. and Richardson, K. S. "Mechanism and Theory in Organic Chemistry", Harper and Row Publishers, New York; 1981, pp. 315-320; and Ross, A. M.; Pohl, T. M.; Piazza, K.; Thomas, M.; Fox, B.; Whalen, D. L., J. Am. Chem. Soc., 1982, 104, p. 1658.) Stereochemical scrambling due to the intermediacy of the allylic carbocation in systems closely related to EpB [such as cyclopentadiene monoepoxide (3)] has been observed. As shown below, hydrolysis of cyclopentadiene monoepoxide (3) under acidic conditions affords all four possible products, cis-4, trans-4, cis-5, trans-5 in a ratio of 25:16:16:43, respectively. (Ross, A. M.; Pohl, T. M.1 Piazza, K.; Thomas, M.; Fox, B.; Whalen, D. L. J. Am. Chem. Soc. 1982, 104, p. 1658.) Thus, literature precedent indicates that the hydrolytic opening of vinyl epoxides under S N 1 conditions is largely stereorandom. ##STR2##
It has also been reported that the product distribution for the opening of EpB under neutral or acidic conditions differs from the product distribution under basic conditions. Acidic conditions result in high regioselectivity for the secondary allylic position, with a small amount of primary allylic product (2-butene-1,4-diol) (Petrov, V. A., et al., Zh. Organ. Khim., 1984, 20, 993.) The presence of only minor amounts of primary allylic products has been suggested as indicative of an A-2-like (bimolecular) transition state. (Ross et al., J. Am. Chem Soc., 1982, 104, 1658.) This, however, may just reflect the relative thermodynamic stabilities of the secondary versus the primary positions and therefore the amount of cationic character at each position. Notwithstanding, the presence of the two allylic products indicates that the transition state involves allylic C-O bond cleavage with a significant amount of carbocation character. Accordingly, an even more thoroughly racemized product than that obtained using basic conditions would be expected when opening acyclic vinyl epoxides using acidic conditions.
Discovering a method for the interconversion of these enantiomeric species while substantially maintaining the optical integrity of the products is needed.
SUMMARY OF THE INVENTION
In accordance with the present invention, a method for the interconversion of enantiomers of an acyclic 1,2-dihydroxy-3-alkene or converting either enantiomer of an acylic 1,2-dihydroxy-3-alkene to a corresponding antipodal 1-hydroxy-2-alkoxy-3-alkene compound has been discovered comprising reacting in an acidic reaction media either enantiomer of an acylic vinyl epoxide (which can be derived from the corresponding acyclic 1,2-dihydroxy-3-alkene) with water, an alcohol, or a mixture thereof to form a product comprising an inverted acyclic 1,2-dihydroxy-3-alkene or an inverted 1-hydroxy-2-alkoxy-3-alkene compound.
In the first embodiment of this invention, the discovered method for the interconversion of enantiomers of an acyclic 1,2-dihydroxy-3-alkene compound comprises reacting in an acidic reaction media either enantiomer of an acylic vinyl epoxide with water to form a product comprising an inverted 1,2-dihydroxy-3-alkene compound.
In the second embodiment of this invention, a method for converting an enantiomer of an acylic 1,2-dihydroxy-3-alkenes to corresponding antipodal 1-hydroxy-2-alkoxy-3-alkene compounds has been discovered, the method comprising reacting in an acidic reaction media either enantiomer of an acylic vinyl epoxide with an alcohol to form an inverted acyclic 1-hydroxy-2-alkoxy-3-alkene compound.
When substantially optically pure acyclic vinyl epoxide compounds are employed in the inventive method, the interconverted acyclic 1,2-dihydroxy-3-alkene or 1-hydroxy-2-alkoxy-3-alkene compound products are also substantially optically pure.
Unexpectedly, a method for the inversion of configuration of enantiomers of acyclic vinyl epoxides has been discovered. At contrast with results at high pH, at low pH (where a thoroughly racemized product was expected) rapid formation of a product displaying highly selective inversion of configuration at the allylic carbon has been discovered. Indeed, the stereoselectivity was higher at low pH than at neutral pH. Thus, this method results in a high yield of substantially optically pure product (when a substantially optically pure acylic vinyl epoxide is employed), with an acceptable reaction rate.
DETAILED DESCRIPTION OF THE INVENTION
The optical purity of the interconverted product produced by this invention is dependent upon the optical purity of the acyclic vinyl epoxide enantiomer reacted with the water or alcohol (or mixture thereof) and to a lesser extent on the alcohol or water selected as a reactant. Preferably, to form a substantially optically pure inverted product, substantially optically pure acyclic vinyl epoxide enantiomers are used.
Acyclic vinyl epoxides that may be interconverted using this method include either enantiomer of the acyclic vinyl epoxides of the following Formula I: ##STR3## wherein R independently represents a straight or branched, substituted or unsubstituted, C 1 -C 20 alkyl, C 2 -C 20 alkenyl, or a C 2 -C 20 alkynyl group, or a substituted or unsubstituted C 4 -C 10 aromatic or heteroaromatic group (with the hetero atom selected from nitrogen, sulfur, or oxygen), with said substituents designated above selected from one or more of the following: halogen, a cyano, a C 1 -C 5 alkoxy, a C 1 -C 5 alkylthio, a C 1 -C 5 ether group, a C 1 -C 5 ester group, a nitro group, a C 1 -C 5 ketone group, or a C 1 -C 5 thioether group.
More preferably, the epoxide is substantially pure and represented by either enantiomer of Formula II as follows: ##STR4## wherein R is as defined previously.
Most preferably, the epoxide is substantially optically pure and represented by either enantiomer of Formula III below: ##STR5## wherein R is as defined previously.
Substantially optically pure acyclic vinyl epoxides or other precursors may be prepared by various known methods, including, for example, chemoenzymatic preparation (as described, for example, in U.S. Ser. No. 854,944, filed Mar. 20, 1992, by N. Boaz); classical chemical resolution; and (as described in Marshall, J. A. et al., Tetrahedron Lett., 1988, 29, 913) Sharpless asymmetric epoxidation of an allylic alcohol, followed by the oxidation of the alcohol to an aldehyde and olefination (simplified for purposes of illustration by Reaction Scheme 1, as follows). ##STR6##
Although the method of preparation of the epoxide is largely immaterial to the present invention, the invention is particularly useful in a biocatalytic resolution process, involving for example, BDO, as depicted by Reaction Schemes 2 and 3 below.
Reaction Scheme 2 shows the process by which a substantially optically pure hydroxy-tosylate (6) may be prepared from BDO. ##STR7## As shown above, in step 1 of Reaction Scheme 2, BDO is converted to (±)-hydroxy-tosylate [(±)-6] using with methods well-known to those skilled in the art. In step 2, (±)-6 is then enzymatically resolved to S-hydroxy-tosylate (S-6) and R-acetoxy-tosylate (R-7) by any number of methods, such as that described in pending U.S. application Ser. No. 854,944. In Step 3, S-6 is separated from R-7 by the recrystallization of the mixture twice to afford substantially optically pure (S)-hydroxy-tosylate S-6 (ppt) and the impure enantiomerically enriched (R)-acetoxy-tosylate R-7(filtrate). In step 4, the substantially optically pure (R)-hydroxy-tosylate R-6 may be obtained from the (R)-acetoxy-tosylate R-7 by chemical removal of contaminants, acid hydrolysis of the acetate, and recrystallization as described, for example, in U.S. Pat. No. 5,126,268.
Reaction Scheme 3 illustrates how hydroxytosylate 6 (either enantiomer) may be further converted to BDO. ##STR8## As shown, Reaction Scheme 3 describes how hydroxytosylate 6 (either enantiomer) may be converted to BDO (same configuration) by a two step sequence: (1) KHCO 3 , DMSO, 60° C.; and (2) aq. NaOH. Also shown by Reaction Scheme 3, the substantially optically pure hydroxy-tosylate 6 may be converted to the antipodal BDO by conversion to epoxide (K 2 CO 3 ) followed by acid-catalyzed water addition (inversion of configuration) according to this invention.
An illustration of the usefulness of the invention is shown by Reaction Scheme 4, immediately hereafter. This reaction scheme is just one of many that may employ the present invention. The inventive step is shown as Steps 2 and 5. As used in the diagram: R-6 represents R-1-tosyloxy-2-hydroxy-3-butene; R-BDO and S-BDO represent the R and S entantiomers of 3-butene-1,2-diol; R-EpB and S-EpB represent the R and S entantiomers of epoxybutene; S-6 represents S-1-tosyloxy-2-hydroxy-3-butene; TsCl represents toluenesulfonyl chloride; and rxtl indicates a recrystallization occurred. ##STR9## As shown in Reaction Scheme 4, steps 4, 5, and 6 are the same as steps 3, 2, and 1, respectively. The scheme demonstrates how any one of the six compounds can be converted into any of the others. Steps 1 and 4 show the formation of an epoxide. Steps 2 and 5 show an embodiment of the invention, where an inversion of configuration occurs during hydrolysis. In the forward direction of steps 3 and 6, the preparation of a tosylate is shown. In the reverse direction of step 3 and 6 conversion of tosylate to diol is shown.
According to the invention, the reaction media is acidic. Preferably, the reaction media is prepared to have a pH level within the range of -5 to 7, more preferably within the range of 0 to 7, and most preferably from 0 to 3. Any Bronsted acid or Lewis acid and mixtures thereof (also referred to herein as "acid catalyst") may be used to make the reaction media acidic. More preferably used as an acid catalyst are mineral acids, sulfuric acid, nitric acid, organic sulfonic acids, sulfonic acid resins, carboxylic acids (such as trifluoroacetic acid, trichloroacetic acid, benzoic acid, and so on), and mixtures thereof. Most preferably, the acid is selected from sulfuric acid, organic sulfonic acids, sulfonic acid resins, and strong carboxylic acids with a pKa of <3. Although not essential, preferably the reaction media is made acidic prior to the contacting of the acyclic vinyl epoxide.
As previously defined, the acyclic vinyl epoxide is reacted with water, an alcohol, or a mixture of both. Preferably the alcohol is defined by the formula R'OH wherein R' represents an unsubstituted or substituted, straight or branched C 1 -C 20 alkyl, C 2 -C 20 alkenyl, or C 2 -C 20 alkynyl group or an unsubstituted or substituted C 4 -C 20 aromatic group (with said substituents designated above selected from one or more of the following: a halogen, a cyano, a C 1 -C 5 alkoxy, a C 1 -C 5 alkylthio, a C 1 -C 5 ether group, a C 1 -C 5 ester group, a nitro group, a C 1 -C 5 ketone group, or a C 1 -C 5 thioether group. More preferably reacted with the epoxide is either water or an alcohol wherein R' represents a C 1 -C 6 straight or branched alcohols (such as methanol, ethanol, n-propanol, i-propanol, n-butanol, s-butanol, i-butanol). A mixture of of water and alcohols may be used in the reaction media, however a mixture of products may result.
The ratio of the alcohol, water, or mixture thereof to acyclic vinyl epoxide substrate effective in this invention is highly variable. Preferably, the amount of water and/or alcohol is from 1 equivalent to a large excess. Preferably, the epoxide and water and/or alcohol are reacted in an appropriate solvent, as known to those skilled in the art. The water and/or alcohol component selected as a reactant may also be used as a solvent.
Preferably, the reaction media is maintained at a low temperature. This low temperature facilitates the selectivity of the inversion reaction. Preferably the reaction media is at a temperature as low as possible while maintaining the reaction media as a liquid and affording an acceptable reaction rate. As used herein an acceptable reaction rate is defined as a reaction having at least 80% (more preferably 90% and most preferably 95%) of the acyclic vinyl epoxide substrate consumed within about 48 hours (more preferably 24 hours and most preferably 12 hours), as detectable by methods known to those skilled in the art including for example vpc (vapor phase chromatography), tlc (thin layer chromatography), 1 H nmr (nuclear magnetic resonance), and so on. The reaction media temperature preferably ranges from about -100° C. to about +100° C. More preferably, the temperature falls within the range from about -20° C. to about 50° C. Most preferably, the temperature of the reaction media is maintained within a range of about 0° C. to about 25° C.
Although not essential, preferably the reaction media is neutralized prior to the recovery of the inverted product. Neutralization may be accomplished, if desired, by any known technique, such as, for example, the addition of aqueous or solid sodium bicarbonate (preferably to a pH of 7 to 9 for soluble acid catalysts). When employed, sulfonic acid resins may be removed by filtration.
The recovery of the inverted product of this invention may be accomplished by any appropriate method known to those skilled in the art. Preferably, the solvent is removed at reduced pressure. The residue may then be dissolved in a suitable organic solvent (such as, for example, dichloromethane, ethyl acetate, or an ether); dried; and concentrated to afford crude product. The crude product may be purified, if desired, by appropriate methods (such as, for example, distillation, crystallization, chromotography, and so on).
The inverted product of this invention may be represented by either enantiomer of Formula IV or Formula V, as shown below. ##STR10## Formula IV results when water is reacted with the epoxide. Formula V results when an alcohol is reacted with the epoxide. As represented in both Formula IV and Formula V, the designations R and R' have the latitude previously defined.
The product produced by this invention may be recovered and used as a commodity chemical as an intermediate for various pharmaceutical or agricultural chemicals. The product may also be manipulated in various chemical reactions for purposes of preparing desired C 4 synthons. This invention is particularly useful when a substantially optically pure acyclic vinyl epoxide is the substrate since the optical integrity of the product is maintained during the interconversion process.
The present invention is now further illustrated by, but is by no means limited to, the following examples.
EXAMPLES
Preparation of S-EpB from S-Hydroxy-tosylate S-6
Ethylene glycol (35 mL) was placed in vacuo for 30 minutes to remove any residual water. S-Hydroxy-tosylate S-6 (99% ee; 8.88 g; 36.7 mmol) was added, and the mixture was stirred and sonicated until most had dissolved. Potassium carbonate (6.58 g; 47.6 mmol; 1.3 equiv) was added, and the reaction mixture was stirred for 1 h at room temperature to afford a homogeneous solution with no residual S-6 as determined by tlc (thin layer chromotography) analysis. The product S-EpB was distilled directly from the reaction flask (over 1 h) at ca. 5 mm Hg and collected in a flask cooled to -78° C. The codistilled water was physically removed to afford 2.1423 g (78%) of S-EpB as a clear, colorless liquid. Properties of the EpB are as follows: EpB:
1 H nmr (300 MHz, CDCl 3 ): 5.522 (2H, m); 5.298 (2H, m); 3.345 (1H, quintet, J=3.15 Hz); 2.967 (1H, t, J=4.43 Hz); 2.657 (1H, dd, J=2.31, 5.17 Hz).
[α]D 20 +20.2° (c. 0.872, pentane).
Determination of Optical Purity of BDO
In the examples where BDO was the product (water addition), the optical purity was determined by conversion to 1-tosyloxy-2-hydroxy-3-butene (6), followed by derivatization of the secondary alcohol as its S-α-methoxy-α-trifluoromethylphenylacetate and 1 H nmr analysis, as described below. Optically active R-BDO (40 mg; 0.45 mmol) was dissolved in pyridine (1 mL) and cooled to 0°. p-Toluenesulfonyl chloride (p-TsCl; 82 mg; 0.43 mmol; 0.95 equiv) was added, and the reaction mixture was thoroughly stirred. The reaction was placed at 4° C. overnight and then diluted with ether (25 mL), washed with H 2 O (10 mL), 3 N HCl (3×10 mL), and NaHCO 3 (10 mL). The etheral solution was dried (with MgSO 4 ) and concentrated to afford 50 mg (46%) of R-hydroxy-tosylate R-6. A portion of R-hydroxytosylate R-6 (16 mg; 0.066 mmol) was dissolved in methylene chloride (1 mL). 4-Dimethylaminopyridine (DMAP; 24 mg; 0.20 mmol; 3 equiv) was added, followed by S-MTPA-Cl (S-α-methoxy-α-trifluoromethylphenylacetyl chloride)(24 μL; 0.13 mmol; 2 equiv). The reaction mixture was stirred at room temperature for 2 h to consume the R-hydroxy-tosylate R-6 by tlc analysis. The mixture was diluted with ether (20 mL), washed with 1N HCl (2×10 mL) and saturated NaHCO 3 (10 mL), dried (MgSO 4 ), and concentrated to afford crude 1-tosyloxy-2-R-(α-methoxy-α-trifluoromethylphenylacetoxy)-3-butene(R,R-8), which was analyzed by 1 H nmr without further purification.
1 H nmr (300 MHz, CDCl 3 ): 7.800 (2H, d, J=8.25 Hz); 7.356 (2H, d, J=8.19 Hz); 5.751 (1H, ddd, J=5.38, 10.46, 16.55 Hz); 5.378 (1H, br d, J=17.05 Hz); 5.247 (1H, br d, J=10.48 Hz); 4.396 (1H, m); 4.066 (1H, dd, J=3.39, 10.20 Hz); 3.906 (1H, dd, J=7.41, 10.22 Hz); 2.451 (3H, s); 2.276 (1H, d, J=4.50 Hz). IR (KBr, cm -1 ): 3520 (s, b); 1650 (w); 1600 (s); 1350 (s); 1170 (s). Anal. Calcd for C 11 H 14 O 4 S: C, 54.53; H, 5.82; N, O. Found: C, 54.84; H, 5.86; N, <0.3.
R,R-8;
1 H nmr (300 MHz, CDCl 3 ): 7.746 * , 7.672 * (2H, 2xd, J=8.26 Hz); 7.5-7.2 (7H, m); 5.5-5.25 (2H, m); 4.2-4.0 (2H, m); 3.539 * , 3.475 * (3H, 2xs); 2.445 (3H, s). IR (neat film, cm -1 ): 1750 (s); 1600 (m); 1370 (s); 1175 (s). FDMS (m/z): 458 (M + ). * Integration of either of these pairs of peaks gave the diastereomeric excess of 9.
Examples I-IV demonstrate the inventive method where an acyclic vinyl epoxide is reacted with water, with the reaction conditions varied. Reaction Scheme 5 is a representation of the reactions of Examples I-IV. ##STR11##
EXAMPLE I
To 5 mL of distilled water was added 17 μL of 3M aqueous H 2 SO 4 (0.05 mmol; 0.01 molar equiv). To this solution was added dropwise 400 μL (5.0 mmol) of optically pure S-EpB (>98% ee)([α]D 20 +8.3° (c. 6.959, i-PrOH), literature for S-EpB, [α]D 25 +8.306 (c. 6.959, i-PrOH), Crawford et al., Can. J. Chem, 1976, 54, 3364. The resulting homogeneous solution was stirred at room temperature for 15 min. No residual EpB was observed by capillary vpc (vapor phase chromatography) analysis. The reaction mixture was then neutralized to pH 7-9 by the addition of several drops of saturated aqueous NaHCO 3 The water was then removed at reduced pressure, and the residue was triturated with dichloromethane (20 mL), dried (Na 2 SO 4 ), and concentrated to afford 82% of a 90:10 mixture of R-(+)-BDO and the isomeric product 2-butene-1,4-diol(9), respectively. The detection of 9 (and any other impurities) was carried out by 1 H nmr (nuclear magnetic resonance) analysis. The optical purity of the R-BDO thus produced was determined to be 92% ee by the analysis described above. Results of all Examples are summarized in TABLE I (following the Comparative Examples). The achiral properties of BDO are as described below.
BDO:
1 H nmr (300 MHz, CDCl 3 ): 5.842 (1H, ddd, J=5.52, 10.51, 16.89 Hz); 5.350 (1H, dd, J=1.67, 17.08 Hz); 5.222 (1H, dd, J=1.07, 10.38 Hz); 4.25 (1H, m); 3.670 (1H, dd, J=3.34, 11.26 Hz); 3.493 (1H, dd, J=7.42, 11.26 Hz); 2.572 (2H, br s). EIMS (m/z): 70 (M + -H 2 O); 57 (M + -CH 2 OH). IR (neat film, cm -1 ): 3340 (s, b); 2920 (m); 2870 (m); 1640 (w).
9:
1 H nmr (300 MHz, CDCl 3 ); 5.765 (2H, t, J=4.18 Hz); 4.203 (4H, d, J=4.20 Hz); 2.781 (2H, br s).
EXAMPLE II
The procedure of Example I was followed in an identical manner except that the solution of water and H 2 SO 4 was cooled to 5° C. in an ice-water bath prior to the addition of the S-EpB. The resulting homogeneous solution was stirred at 5° for 45 min., at which time substantially all EpB had been consumed according to vpc analysis (after 15 min residual EpB was observed). The acid was neutralized to pH 7-9 by the addition of several drops of saturated aqueous NaHCO 3 , and the solvent was removed at reduced pressure. The residue was triturated with dichloromethane (20 mL), dried (Na 2 SO 4 ), and concentrated to afford 330 mg (75%) of a 95:5 mixture of R-(+)-BDO and 9, respectively, by 1 H nmr analysis. The optical purity of the R-BDO thus produced was determined to be 94% ee. Results are summarized in TABLE I. All achiral properties of BDO are as described previously.
[α]D 20 +44.1° (c. 2.86, i-PrOH) (rotation corrected for the presence of achiral 9).
EXAMPLE III
The procedure was similar to that described in Example 1 except that S-EpB was added to a 1M sulfuric acid solution (1.67 mL of 3.0M H 2 SO 4 and 3.33 mL H 2 O; pH 0) at room temperature. The mixture was stirred at room temperature for 1 h to afford 339 mg (77% total) of an 89:11 mixture of R-(+)BDO and 9, respectively (1H nmr analysis). In the manner described previously, the optical purity of the BDO was determined to be 82% ee.
[α]D 20 +37.6° (c. 2.804, i-PrOH)(rotation corrected for the presence of achiral 9).
EXAMPLE IV
The procedure was similar to that described in Example 1 except that S-EpB (5 mmol) was added to p-toluene sulfonic acid hydrate (p-TSA, 48 mg; 0.25 mmol; 0.05 equiv) in 5 mL of water at room temperature. EpB was substantially consumed after 1 h (vpc analysis) and workup afforded 365 mg (83% total) of R-(+)-BDO contaminated with 12% of 9 and a small amount of p-TSA. In the manner described previously, the optical purity of R-BDO was determined to be 84% ee. Results are summarized in TABLE I. [α]D 20 +39.7° (c. 2.662, i-PrOH) (rotation corrected for the presence of achiral 9).
Examples V-VII demonstrate the inventive method where an acylic vinyl epoxide is reacted with different alcohols. Reaction Scheme 6 is a representation of the reactions of Examples V-VII where R' is defined individually for each example. ##STR12##
EXAMPLE V
The procedure was similar to that described in Example 1 except that CH 3 OH was substituted for the water component (R' is --CH 3 ), thus forming R-2-methoxy-3-butene-1-ol (R-10a), in the following manner. Substantially optically pure S-EpB (350 mg; 5.0 mmol) was dissolved in methanol (5 mL) and cooled to 0° C. A catalytic amount of sulfuric acid (3M; 17 μL; 0.05 mmol; 0.01 equiv) was added and the reaction mixture was stirred at 0° C. for 1 h and then warmed to room temperature for 1 h. Solid sodium bicarbonate (10 mg) was added, and the solvent was removed at reduced pressure. The residue was triturated with dichloromethane, diluted with ether, dried (MgSO 4 ), and concentrated to afford 379 mg (74%) of the mixture of 2-methoxy-3-butene-1-ol (R-10a) and the isomeric product 4-methoxy-2-butene-1-ol (11a). 1 H nmr analysis indicated a ratio of 10a:11a of 95:5, while capillary vpc (vapor phase chromatography) using a chiral Cyclodex-B column indicated >98% ee for R-10a. Results are summarized in TABLE I.
R-10a:
1 H nmr (300 MHz' CDCl 3 ): 5.658 (1H, ddd, J=7.35, 9.94, 17.52 Hz); 5.313 (1H, d, J=19.08 Hz); 5.297 (1H, d, J=9.71 Hz); 3.698 (1H, m); 3.55 (2H, m); 3.332 (3H, s); 2.217 (1H, br s ). IR (neat film, cm -1 ): 3400 (s, b); 1640 (w). EIMS (m/z): 101 (M + -H), 85 (M + -OH), 71 (M + -CH 2 OH). [α]D 20 -44.8° (c. 0.995, methanol)
EXAMPLE VI
Example I was followed with the exception that CH 3 CH 2 OH was substituted for the water component (R' is --CH 2 CH 3 ), thus forming R-2-ethoxy-3-butene-1-ol (R-10b), in the following manner. Sulfuric acid (3M; 17 μL; 0.05 mmol; 0.01 equiv) was dissolved in 5 mL of ethanol and cooled to 0° C. Optically pure S-EpB (350 mg; 5.0 mmol) was added dropwise and the reaction mixture was allowed to warm to room temperature. After 1.5 h at room temperature EpB had been substantially consumed according to vpc analysis. Excess solid sodium bicarbonate was added, and the solvent was removed at reduced pressure. The residue was triturated with dichloromethane (10 mL) and ether (10 mL), dried (Na2SO 4 ), and concentrated to afford 454 mg (78%) of a 92:8 mixture of R-10b:11b (4-ethoxy-2-butene-1-ol) according to 1 H nmr analysis. Capillary vpc analysis using a chiral Cyclodex-B column indicated 95.6% ee for R-10b. Results are summarized in TABLE I.
R-10b:
1 H nmr (300 MHz, CDCl 3 ): 5.692 (1H, ddd, J=7.17, 10.34, 17.4 Hz); 5.308 (1H, d, J=16.86 Hz); 5.264 (1H, d, J=9.58 Hz); 3.82 (1H, m); 3.7-3.45 (3H, m); 3.394 (1H, dd, J=7.00, 9.34 Hz); 2.065 (1H, br s); 1.208 (3H, t, J=7.01 Hz). IR (neat film, cm -1 ): 3420 (s, b); 1640 (w).
EXAMPLE VII
Example I was followed with the exception that (CH 3 ) 2 CHOH was substituted for the water component [R' is --CH(CH 3 )2], thus forming R-2-(2-Methylethoxy)-3-butene-1-ol (R-10c), in the following manner. Sulfuric acid (3M; 17 μL; 0.05 mmol; 0.01 equiv) was dissolved in 5 mL of isopropanol and cooled to 0° C. Substantially optically pure S-EpB (350 mg; 5.0 mmol) was added dropwise and the reaction mixture was allowed to warm to room temperature and stirred overnight (20 h) to completely consume EpB by vpc analysis. Excess solid sodium bicarbonate was added, and the solvent was removed at reduced pressure. The residue was triturated with dichloromethane (10 mL) and ether (10 mL), dried (Na2SO 4 ), and concentrated to afford 455 mg (70%) of a 84:16 mixture of R-10c:11c [4-(2-methylethoxy)-2-butene-1-ol]by 1 H nmr analysis. Capillary vpc analysis using a chiral Cyclodex-B column indicated 88.4% ee for R-10c. Results are summarized in TABLE I.
R-10c:
1 H nmr (300 MHz, CDCl 3 ): 5.705 (1H, ddd, J=6.95, 10.40, 17.32 Hz); 5.300 (1H, d, J=17.53 Hz); 5.231 (1H, d, J=10.49 Hz); 3.95 (1H, m); 3.700 (1H, m(7), J=6.11 Hz); 3.539 (1H, dd, J=3.65, 10.93 Hz); 3.474 (1H, dd, J=7.64, 11.22 Hz); 2.085 (1H, br s); 1.169 (3H, d, J=6.17 Hz); 1.148 (3H, d, J=5.98 Hz). IR (neat film, cm -1 ): 3430 (s, b); 1640 (w).
Comparative Examples I-IX illustrate the reaction of acylic vinyl expoxides with water in non-acidic media.
COMPARATIVE EXAMPLE I
The procedure was similar to that described in Example I except that S-EpB (5 mmol) was stirred with 1N NaOH (5 mL) and afforded R-(+)-BDO contaminated with various other materials (352 mg crude). As analyzed by the techniques previously described, the R-BDO was found to possess 30% ee, as shown in TABLE I.
COMPARATIVE EXAMPLE II
The procedure was similar to that described in Example I except that S-EpB (5 mmol) was stirred with potassium carbonate (1.04 g; 7.5 mmol; 1.5 equiv) at room temperature for 10 days to consume EpB. Workup afforded R-(+)-BDO free of 9 (343 mg, 78%) as determined by 1 H nmr analysis. As analyzed by the techniques previously described, the R-BDO was found to possess 46% ee, as shown in TABLE I.
[α]D 20 +23.5° (c. 3.130, i-PrOH).
COMPARATIVE EXAMPLE III
The procedure was similar to that described in Example I except that S-EpB (5mmol) was stirred for 14 days in 5 mL of aqueous pH 7 phosphate buffer (VWR scientific). Workup afforded R-(+)BDO (72%) contaminated with 1% 9 as determined by 1 H nmr analysis. As analyzed by the techniques previously described, the R-BDO was found to possess 85% ee, as shown in TABLE I.
[α]D 20 +38.6° (c. 3.025, i-PrOH).
COMPARATIVE EXAMPLE IV
The procedure was similar to that described in Example I except that S-EpB (5 mmol) was stirred in water (5 mL) at room temperature for 2.5 days to afford 122 mg (28%) of R-(+)-BDO free of 9 as determined by 1 H nmr analysis. As analyzed by the techniques previously described, the R-BDO was found to possess 87% ee, as shown in TABLE I.
[α]D 20 +41.1° (c. 1.080, i-PrOH).
COMPARATIVE EXAMPLE V
The procedure was similar to that described in Example I except that S-EpB (5 mmol) was stirred in water (5 mL) at room temperature for 10 days to afford R-(+)-BDO (65%) free 9 as determined by 1 H nmr analysis. As analyzed by the techniques previously described, the R-BDO was found to possess 84% ee, as shown in TABLE I.
[αD 20 +39.5° (c. 2.990, i-PrOH).
COMPARATIVE EXAMPLE VI
The procedure was similar to that described in Example I except that S-EpB (5mmol) was stirred in water (5 mL) at 45° C. for 50 h. The reaction did not completely consume the EpB, and workup at this point afforded R-(+)-BDO (189 mg; 43%) free of 9 as determined by 1 H nmr analysis. As analyzed by the techniques previously described, the R-BDO was found to possess 80% ee, as shown in TABLE I.
[α]D 20 +37.4° (c. 2.970, i-PrOH).
COMPARATIVE EXAMPLE VII
The procedure was similar to that described in Example 1 except that S-EpB (5 mmol) was stirred in water (5 mL) at 65° C. and allowed to react for 30 h to afford 246 mg (56%) of R-(+)-BDO free of 9 as determined by 1 H nmr analysis. As analyzed by the techniques previously described, the R-BDO was found to possess 80% ee, as shown in TABLE I.
[α]D 20 +37.8° (c. 3.020, i-PrOH).
COMPARATIVE EXAMPLE VIII
The procedure was similar to that described in Example 1 except that S-EpB (5 mmol) was added to water at 65° C., and the mixture was then heated to 100° C. for 3 hours to afford 128 mg (29%) of R-(+)-BDO contaminated with 1% of 9 as determined by 1 H nmr analysis. As analyzed by the techniques previously described, the R-BDO was found to possess 72% ee, as shown in TABLE I.
[α]D 20 +33.3° (c. 1.245, i-PrOH).
COMPARATIVE EXAMPLE IX
The procedure was similar to that described in Example 1 except that S-EpB (5 mmol) was added to water (5 mL) containing Amberlyst 15™ (17,5 mg; 5 wt. %) (obtained from Aldrich Chemical Co.). The reaction mixture was stirred at room temperature overnight at which time the EpB was consumed as indicated by vpc analysis. The catalyst was removed by filtration and isolation as above afforded R-(+)-BDO contaminated with 10% 9 by 1 H nmr analysis (242 mg; 55% total). As analyzed by the techniques previously described, the R-BDO was found to possess 86% ee, as shown in TABLE I.
[α]D 20 +40.6° (c. 2.77, i-PrOH) (rotation corrected for the presence of achiral 9).
TABLE I__________________________________________________________________________ Relative Amounts TotalExample # R'OH Catalyst R-BDO.sup.1 S-BDO.sup.2 BDO:9.sup.3 % ee Yield__________________________________________________________________________I H.sub.2 O H.sub.2 SO.sub.4 96.sup.b 4.sup.b 90:10 92% 82% (1 mole %)II H.sub.2 O H.sub.2 SO.sub.4 97.sup.b 3.sup.b 95:5 94% 75% (1 mole % 5° C.)III H.sub.2 O H.sub.2 SO.sub.4 91.sup.b 9.sup.b 89:11 82% 77% (100 mole %)IV H.sub.2 O p-TSA 92.sup.c 8.sup.c 88:12 84% 83%V CH.sub.3 OH H.sub.2 SO.sub.4 99.2.sup.d 0.8.sup.d 95:5 98.4% 79%VI CH.sub.3 CH.sub.2 OH H.sub.2 SO.sub.4 97.8.sup.d 2.2.sup.d 92:8 95.6% 78%VII (CH.sub.3).sub.2 -- H.sub.2 SO.sub.4 94.2.sup.d 5.8.sup.d 84:16 88.4% 70% CHOHC.E.I.sup.a H.sub.2 O NaOH 47.5.sup.e 52.5.sup.e >99:1 30% 80%C.E.II.sup.a H.sub.2 O K.sub.2 CO.sub.3 73.sup.b 27.sup.b >99:1 46% 78%C.E.III.sup.a H.sub.2 O phosphate buffer 92.5.sup.e 7.5.sup.e 99:1 -- 72%C.E.IV.sup.a H.sub.2 O -- 93.5.sup.b 6.5.sup.b >99:1 87% 28% (25 days)C.E.V.sup.a H.sub.2 O -- 92.sup.b 8.sup.b >99:1 84% 65% (10 days)C.E.VI.sup.a H.sub.2 O -- 90.sup.e 10.sup.e -- 80% 43% (45° C., 50 hours)C.E.VII.sup.a H.sub.2 O -- 90.sup.e 10.sup.c -- 80% 56% (65° C., 30 hours)C.E.VIII.sup.a H.sub.2 O -- 86.sup.b 14.sup.b 99:1 72% 29% (100° C., 3 h)C.E.IX.sup.a H.sub.2 O Amberlyst 15 ™ 93.sup.c 7.sup.c 90:10 86% 55%__________________________________________________________________________ .sup.1 or R10 where applicable .sup.2 or S10 where applicable .sup.3 or 10:11 where applicable .sup.a Comparative Examples .sup.b Enantiomeric ratio determined by comparison of optical rotation of the BDO produced with the maximum value of +47.0° calculated from the optical rotation ([α].sub.D.sup.20 +41.1°) and known optical purity (87% ee) from Example IV. .sup.c Enantiomeric ratio determined by conversion of the BDO to 1tosyloxy-3-buten-2-yl Rmethoxy-trifluoromethylphenylacetate and integration of the diastereomeric signals by .sup.1 H nmr as previously described. .sup.d Determined by capillary vpc on a chiral CyclodexB column (J&W Scientific). .sup.e Enantiomeric ratio determined by taking into account the presence of 2butene-1,4 diol.
The following preparations detail the determination of the absolute configuration of 2-methoxy-3-butene-1-ol by independent synthesis, proving that methanolysis occurred with inversion of configuration. Thus, the negative rotation of R-1-benzyloxy-2-methoxy-3-butene (shown below as R-12) prepared below compares with S-(+)-1-benzyloxy-2-methoxy-3-butene) obtained by independent synthesis from S-BDO. Inversion of configuration was implicated for R-10b (Example VI) and R-10c (Example VII) by comparison with R-10a (Example V). ##STR13##
R-1-Benzyloxy-2-methoxy-3-butene R-12
Methyl ether R-10a (103 mg; 1.0 mmol) was dissolved in dichloromethane (1 mL). Triethylamine (0.21 mL; 1.5 mmol; 1.5 equiv) was added followed by benzoyl chloride (128 μL; 1.1 mmol; 1.1 equiv). The reaction mixture was stirred at room temperature for 2.5 days to completely consume R-10 by tlc analysis. The reaction mixture was diluted with ether (20 mL), washed with 1N HCl (2×10 mL) and saturated aqueous sodium bicarbonate (10 mL), dried (MgSO 4 ), and concentrated to afford 213 mg (>99%) of R-12.
R-12:
1 H nmr (300 MHz, CDCl 3 ): 8.058 (2H, d, J=7.32 Hz); 7.562 (1H, t, J=7.46 Hz); 7.439 (2H, t, J=7.41 Hz); 5.794 (1H, ddd, J=7.24, 10.32, 17.40 Hz); 5.398 (1H, d, J=18.43 Hz); 5.349 (1H, d, J=11.12 Hz); 4.385 (1H, dd, J=4.50, 11.48 Hz); 4.321 (1H, dd, J=6.51, 11.52 Hz); 3.984 (1H, q, J=6.50 Hz); 3.383 (3H, s). IR (neat film, cm -1 ): 1720 (s); 1600 (m). EIMS (m/z): 176 (M + -CH 2 O); 84 (M + -PhCOOH). [α]D 20-21 .5 ° (c. 1.020, methanol).
Configuration Determination: S-1-Benzoyloxy-2-hydroxy-3-butene (S-13)
S-BDO (125 mg; 1.42 mmol) was dissolved in dichloromethane and cooled to 0° C. Triethylamine (0.24 mL; 1.70 mmol; 1,2 equiv) was added followed by benzoyl chloride (148 μL; 1.28 mmol; 0.9 equiv). The reaction mixture was allowed to warm to room temperature overnight to completely consume benzoyl chloride by tlc analysis. The reaction mixture was diluted with ether (50 mL), washed with 1N HCl (2×15 mL) and saturated aqueous sodium bicarbonate (15 mL), dried (MgSO 4 ), and concentrated. The crude product was flash chromatographed and eluted with 30% ether in pentane to afford 171 mg (70%) of S-13.
S-13:
1 H nmr (300 MHz, CDCl 3 ): 8.057 (2H, d, J=7.41 Hz); 7.579 (1H, t, J=7.47 Hz); 7.450 (2H, t, J=7.72 Hz); 5.950 (1H, ddd, J=5.47, 10.50, 16.36 Hz); 5.453 (1H, d, J=17.29 Hz); 5.289 (1H, d, J=10.45 Hz); 4.53 (1H, m); 4.432 (1H, dd, J=3.53, 11.47 Hz); 4.298 (1H, dd, J=7.14, 11.43 Hz); 2.27 (1H, br s). IR (neat film, cm -1 ): 1400 (s, b); 1715 (s); 1600 (w); 1580 (w). FDMS (m/z): 192 (M + ).
[α]D 20 -6.0° (c. 1.066, methanol).
S-1-Benzoyloxy-2-methoxy-3-butene (S-12)
Powdered potassium hydroxide (83 mg; 1.48 mmol; 2.5 equiv) was slurried in DMSO (2.5 mL) and stirred for five min. Benzoate S-13 (114 mg; 0.593 mmol) was added in 2 mL of DMSO followed by iodomethane (74 μL; 1.2 mmol; 2 equiv). The reaction mixture was stirred for 45 min at room temperature to completely consume S-13 (tlc analysis) and then poured into 1:1 ether:pentane (50 mL). The organic solution was washed with water (5×20 mL), dried (MgSO 4 ), and concentrated. The crude product was flash-chromatographed and eluted with 1:9 ether:pentane to afford 33 mg (27%) of S-12. All achiral physical properties are as reported above.
[α]D 20 +18.0 (c. 0.662, methanol).
The invention has been described in detail with particular reference to preferred embodiments thereof, but it will be understood that variations and modifications can be effected within the spirit and scope of the invention. All patents, patent applications (published or unpublished, domestic or foreign), scientific literature, books and other prior art cited herein are each incorporated herein by reference for the teaching therein pertinent to this invention. | In accordance with the present invention, a method for the interconvertion of the enantiomers of acyclic 1,2-dihydroxy-3-alkenes or for converting either enantiomer of acylic 1,2-dihydroxy-3-alkenes to the corresponding antipodal 1-hydroxy-2-alkoxy-3-alkene compounds has been discovered, comprising reacting in an acidic reaction media either enantiomer of an acylic vinyl epoxide (which can be derived from the corresponding acyclic 1,2-dihydroxy-3-alkene) with water, alcohol, or a mixture thereof. When substantially optically pure acyclic vinyl epoxide compounds are employed in the inventive method, the interconverted acyclic 1,2-dihydroxy-3-alkene or 1-hydroxy-2-alkoxy-3-alkene compound products are also substantially optically pure. | 2 |
BACKGROUND OF THE INVENTION
This application is an improvement in the novel flavoring composition set forth in U.S. Pat. No. 4,571,342 to DiCicca et al. Issued Feb. 18, 1986 for charcoal broiled flavor composition.
The enhancement of foods products with meat-like flavors of the type set forth in the aforesaid DiCicca patent has enjoyed considerable commercial success. The demand for meat flavored products continues and the preparation of sausage and purees or meat analogs, pet foods and meat extended products are all benefitted by a meat flavor characterized as having a charcoal broiled nature.
The DiCicca et al. process involves, as is stated in the patent, subjecting a film of fat or oil to temperatures within the range of 302° F.-855° F. in the presence of oxygen for a period of time effective to develop charcoal or charred meaty flavor notes, and collecting the treated fat or oil. Unfortunately, when one scales such a process to a significant degree there is an ineffective use of the equipment and the reaction is inconsistent. The flavors that are produced can generate harsh notes which tend to detract from the overall flavorful impact of the composition.
SUMMARY OF THE INVENTION
Basically, the present invention carries forward the teachings of DiCicca et al. in a controllable manner whereby the flavor development is enhanced by a continuous exothermic reaction, which is thereafter quenched to a temperature whereat the exothermic reaction is eventually terminated. The exothermic reaction is carried out in the presence of air ideally, although pure oxygen may also be employed; stated as a level the oxygen present, 1 to 11/2 parts oxygen to 1 part fat or oil will be employed, it being understood that the fat or oil will contain the notes responsible for the charcoal broiled taste development of the flavor process. Exothermy is carried out in a thin film heat exchanger wherein the hot fat or oil is distributed as a thin film and undergoes a phase change into smoke, the exothermy continuing throughout the process balance, whereby the smoke is heated exothermically and leaves the heat exchanger at a temperature of at least 650° F., typically 670°-700° F., the heat exchanger per se being at a temperature of at least 600° F. Upon exiting the heat exchanger, the smoke is rapidly quenched say in less than 20 seconds and commonly in about 10 seconds, by means which will become apparent in the accompanying description, until the smoke flavor is recovered as a flavored oil; the oil phase will be at a temperature within the range of from 210° F. to 230° F. at this point. Incident to this process there will be a 10-20% dissipation of the smokey constituents containing tarry and acrid notes which will eventually be spent as vapor to the atmosphere.
Through this medium of thin film exothermy, smoke that is generated and eventually recovered as a flavoring oil will be generally free of a harsh flavor notes. It is found that such notes are removed as the typically 10-20% separated phase created incident to cooling.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a diagram of the processing steps utilized in producing a charcoal broiled flavor while simultaneously removing tarry and acrid notes to yield an improved flavor.
DETAILED DESCRIPTION OF THE INVENTION
The invention will now be described by reference to the accompanying drawing wherein FIG. 1 displays the general overall pattern for a flavor and aroma collection process. The tallow which may be beef, kosher beef, chicken, lard, turkey and like flavoring fats and oils is heated in an open kettle to a temperature exceeding 160° F. and generally at such temperature that it becomes fluid. Referring to the accompanying drawing, the kettle 10 is charged through line 12 to a filter 14 whereat undesired materials are removed and whereafter the filtrate passes line 16 to a positive displacement feed pump 18 and enters through line 20 into a rototherm 22. The temperature in the lines 12, 16 and 20 is generally heated to the neighborhood of 200° F. prior to entry into the rototherm 22.
At the same time air is metered by means not shown through line 24 also entering rototherm 22. The air is compressed and then filtered to keep it clean; in this way a good quality of oxygen in particular and air preferably is charged to the rototherm. The rototherm is maintained under a slight positive pressure not exceeding 15-20 pounds per square inch guage.
The heated fluid in the rototherm is distributed as a thin film being generally of a thickness no greater than 1/16th of an inch and typically somewhere between 1/32nd and 1/16th of an inch. The fat phase will transfer to an exothermic gaseous phase. Considered in combination, these phases (liquid and gaseous fat), will be treated for a period not exceeding 2 minutes, normally in the neighborhood of 90 seconds or less. During this retention time, the fat phase will be elevated in temperature by the heat exchanger in the presence of air, the fat being charged in such manner that the initial liquid phase exists a very minor percent of the total time in the rototherm, typically less than 20 seconds. Under ideal conditions the hot film will be rapidly vaporized, vaporization commencing at above 600° F. generally.
The flavor developed upon exiting the rototherm is thereupon fed through line 26 to a cooler which in the drawing is a heat exchanger 28, cold water issuing at 32 from the cooler and the product issuing at line 34 therefrom at a temperature as indicated generally within the range of from 210° F. to 230° F. At this point the flavor process has been essentially terminated and the flavorant per se will exist in the form of a liquid, a minor portion by weight of the reacted gaseous constituents being spent through vapor line 36, typically 10-20% of the reaction product. The vapor phase in line 36 passes a suitable vacuum pump 38, fresh air being drawn in at 40 and the air-smoke mixture containing harsh tarry and acrid notes passing line 42 to a thermal incinerator 44, the combustion products exiting at 46. The cooling temperature of from 210° F. to 230° F. is critical to the invention because it will determine the percentage yield and the amount of spent vapor. The higher the cooling temperature at 36 the greater then amount of spent vapor and consequently the lower percentage yield. At the aforesaid temperature range, an acceptable yield is obtained but yet a majority of off flavor notes are removed in the spent vapor.
The flavorant of use in line 52 is filtered in a liquid state to remove carbonaceous particles at either 48 or 50 which are operated independently and alternately. The thus filtered fluid passing line 54 enters a positive displacement pump 56 from which it is displaced at 58 to a collection vessel 60 and thereafter is filtered again by passing line 64 and filtration device 62. The material is eventually exposed to an antioxidant which is admixed therewith in pump 66 and then discharges from pump 66 to line 68 to a votator which cools and mixes the flavorants and the antioxidants at 70. The product produced is recovered at 72. The votator 70 is operated so as to admit cold water to the jacket thereof, thus further cooling the flavoring liquid, the material collected at 72 being 100° F. or less.
It should be noted that the rototherm 22 is specially modified by closing off the vapor vent that would normally remove vapors while concentrating; secondly, the heat exchange medium which is normally a heat transfer fluid has been replaced by an electric resistance heater; e.g. a standard thin film processor such as is manufactured by Artison Industries, Inc. and is described in their bulletin No. 4027-I as an Artison Rototherm E will be the desired processor, the processor being a 1 square foot heat centrifugally-wiped exchanger; it will be noted that the 1 square foot refers to the heating surface per se of the process.
Basically, the flavor process is critical to the present invention. The flavors that are generated and that are common to this invention occur during the exothermic heating. The temperature of the fat will eventually be at a point where it exceeds the surface temperature of the heat exchanger itself. Thus, as indicated previously the minimum heat exchange surface temperature will be in excess of 600° F. measured at the heat exchanger surface and, in a relevantly brief period of time, exothermy will be experienced resulting in a temperature increase of the fat generally of 50° F. with regard to the temperature of the heating surface itself, a range of 40° F. to 75° F. being the terminal temperature of the controlled exothermy above the temperature of the heat exchange surface.
It will be understood that this process therefore involves a very careful control of heat temperatures by the processes set forth herein. There is greater control of the reaction and particularly the heat temperature process thereof which results in a more uniform end product and avoid the formation of off flavor notes. In addition, the process desirably involves subsequently cooling in a relatively rapid fashion and the spending of a minor weight percent of the vapors as at line 36 so as to further separate undesired flavor notes.
The invention will now be described by reference to operative examples.
EXAMPLE 1
Beef tallow derived by taking fresh meat scraps from a meat processing operation is treated. The tallow will contain the desired flavor precursors. The following physical and chemical properties and limits are achieved in the final product.
______________________________________Property Limits______________________________________Moisture 1.0%(Max.)Free Fatty Acid 1.0-4.0%Peroxide Value 5-36%Iodine Value 36-45Unsaponifiables 1.25%(Max.)Antioxidant BHA 50-60 ppm(From Tenox 7) (On Fat Basis)______________________________________
The foregoing process is practiced and the physical and chemical properties are realized in a process having the following characteristics.
______________________________________NATURAL GRILL FLAVORS Preferred OptimalProperty Target Range______________________________________Finished Product Flow Rate (lbs./hr.) 33 31-36Air Flow Rate (cubic ft./hr.) 150 140-160Product Reaction Temp. (°F.) at the 675 670-680exit of the RotothermVapor Sep. Temp. (°F.) at point 34 on 220 210-230flow chartVacuum (in. Hg) at point 36 on flow chart 0.40 0.20-1.0Heat Temp (°F.) measured at the inside 620-640 610-670surface of reactor 22 of the inside cavityof wall reactor______________________________________
The finished product flow rate will generally be 85% of the entering flow rate to the rototherm. The product reaction temperature at the exit and of the rototherm will be the gas temperature, that is, the vapor temperature leaving the rototherm. The vapor separation temperature will be the temperature at point 34 on the flow chart.
It should be noted, that in line 36 there is a slight vacuum to facilitate the removal of the vapors that are unwanted and to be discarded. The heater temperature will be as stated, that which is measured at the inside surface of the reactor 22 at the inside cavity wall of the reactor.
The foregoing conditions represent those which may be practiced in treating beef fat, kosher beef, chicken, port or turkey. It is contemplated that the foregoing conditions generally apply to the treatment of all foodstuffs.
The product produced by this process can be used as a liquid as such and can be sprayed or otherwise applied, all of which is within the skill of the calling. On the other hand, the product itself may be spray-dried or otherwise reduced to a free-flowing powder, all of which similarly will occur to those skilled in the art. The product aromas will generally have an improved charcoal type overall flavor, as indicated previously relative to that of DiCicca et al. | A process of producing a charcoal broiled flavor is provided by distributing a heated fat or oil as a thin film which is exposed to a temperature of at least 600° F. for a period of time less than 2 minutes to exothermically heat the fat to at least 650° F. and thereafter rapidly cooling the flavor product to a temperature less than 220° F., a minor fraction of the exothermically heated oil being spent as waste vapor. | 0 |
BACKGROUND
[0001] The invention enables size and cost reductions for low-cost electronic devices based on embedded microprocessors with memory requirements for fixed data such as look-up tables or programs.
[0002] Electronic devices often use microprocessors to perform a variety of tasks ranging from the very simple to the very complicated. When a device, such as a remote control device, a mobile device, etc., is designed for a specific function or functions, the programs corresponding to those functions are usually, once development is complete, stored in a Read Only Memory (ROM). Other fixed data may also be stored in ROM, such as a look-up table for values of some function required for computation, such as an exponential or logarithm function, or trigonometric functions.
[0003] A low cost and compact form of ROM is Mask Programmed ROM. In a Mask-Programmed ROM, the address is decoded to provide a logic level on one of a number of signal lines corresponding to the address. The address lines cross the bit lines corresponding to the desired output word, and a transistor is placed at the crossing of every address line and bit line where a binary “1” is the desired bit output for that address. Such a ROM is in fact equivalent to a gigantic OR-gate for each output bit, determining it to be a “1” if address A1.OR.A2.0R.A3 . . . is active, else determining it to be a “0”.
[0004] The transistors used to indicate a stored ‘1’ provide the inputs to each multi-input OR gate. FIG. 1 shows such a ROM, wherein a word of length 32 bits is stored against each of 1024 addresses. Where a larger memory is desired, the pattern of FIG. 1 may be repeated to form successive rows of 1024 words, and row-select lines are provided to enable output from a selected row, which, together with activation of a particular column address line, selects a particular word.
[0005] The transistors are placed by means of a custom-designed diffusion and/or contact and/or metallization mask used during the fabrication process, adapted for the desired bit pattern. Since mask-making is expensive, this is used only when the ROM contents are expected to be fixed for high volumes of production units. Other forms of memory, such as Electronically or UV-erasable and Reprogrammable Read Only Memory (EAROM, EEROM, EPROM, “FLASH” memory, etc.) and other more recent non-volatile memory developments such as ferroelectric memory are therefore more usually selected in preference to Masked ROM because of the convenience that the memory may be manufactured before the desired contents are known and filled later, as well as modified in-service. It might be said that the silicon area and consequent cost advantage of Mask Programmed ROM have to date not been sufficient to outweigh the convenience of in-situ programming.
[0006] Some solutions that could give the advantages of Masked ROM while preserving some flexibility comprise storing mature sections of program, i.e., subroutines, or fixed tables for mathematical functions or character set displays in Masked ROM, but linking and invoking them by a smaller program in reprogrammable memory. That way, if a Masked-ROM routine needs to be replaced, the replacement routine only need be placed in reprogrammable memory and the Masked-ROM version bypassed, a process known as “patching”. However, the area advantages of Masked ROM have still not been sufficient to encourage widespread use of this technique. Thus, there is a need for fixed-content memory that is significantly more compact and economic than Masked ROM has been hitherto.
SUMMARY
[0007] Exemplary embodiments of the present invention comprise a method for compressing data for storage in a memory. According to one embodiment, the method comprises forming a set of values based on a monotonically ordered series of look-up table values. For one or more paired values in the set, the exemplary method generates a difference of the values in the pair. After replacing one of the values in the pair with a value based on the differences to modify the set, the exemplary method stores final values based on the modified set in memory.
[0008] According to one embodiment, the remaining values in the modified pairs remain unaltered. After this first iteration, final values based on the modified set are stored in memory. Alternatively, additional iterations may be performed to further compress the data storage. For example, in a second iteration, the exemplary method forms pairs between the unmodified values and forms pairs between the modified values, and generates new differences of the values in the new pairs. Subsequently, the exemplary method modifies the current set by replacing one of the values in the pairs with a value based on the differences. This process repeats until the predetermined number of iterations has been completed. After completing the final iteration, final values based on the modified set of values produced by the final iteration are stored in memory.
[0009] According to another embodiment, the remaining values in the modified pairs are replaced with values generated based on the sum of the values in the pair. After this first iteration, concatenating the sum and difference of each pair generates the final values. Alternatively, additional iterations may be performed to further compress the data storage. For example, in a second iteration, the exemplary method forms pairs between the sum values and forms pairs between the difference values, and generates new sums differences of the values in each of the new pairs. This process repeats until the predetermined number of iterations has been completed. After completing the final iteration, concatenating the sums and differences corresponding to the pairings of the final iteration generates the final values.
[0010] In one embodiment, a ROM for storing a number 2 N1 quantities of word length L1 is compressed from a total size of L1×2 N1 bits to a ROM that stores 2 N2 words of L2 bits, a total of L2×2 N2 bits, where L2>L1 and N2<N1, by use of an inventive algorithm.
[0011] One application is for providing a look-up table for a regular function F(x) where the table is addressed by a binary bit pattern corresponding to x and outputs the value F pre-stored at that location. In this case, a first order compression replaces alternate values of the function with their delta values from the preceding address. Alternatively, each pair of adjacent values may be replaced by their sum, with the least significant bit (LSB) discarded, and their difference. When the function is regular, the difference between successive values is much smaller than the function value itself and therefore can be stored in fewer bits.
[0012] A 2 nd order algorithm can comprise repeating the compression procedure, taking as input the array of even-address values from the first stage, and separately the odd-address delta-value array, thereby obtaining a function value, two first order differences and a second order difference in replacement for four function values. The second order differences are usually even smaller than the first order differences, and therefore can be stored using even fewer bits than the first order differences, achieving further compression. A systematic procedure is disclosed for constructing compression algorithms of higher order using a Fast Walsh Transform based on a modified Butterfly operation in which the LSB of the sum term is discarded. Values are reconstructed using the inverse transform upon reading the ROM.
[0013] A second implementation stores blocks of numerically adjacent values by storing a common or nearly common most significant bit (MSB) pattern and different LSB patterns, thus reducing the average number of bits per value stored. It can allow more convenient block sizes, i.e., regular block sizes, if the common most significant bit patterns in a block are allowed to differ by up to + or −1. Extra bits associated with the least significant parts then determine if the common most significant part must be incremented or decremented for a particular retrieved value, or not. The second implementation allows simpler reconstruction than the first implementation.
[0014] The present invention also comprises memory for storing a plurality of look-up table values, where each look-up table value is associated with an address comprising a plurality of address symbols. One exemplary memory comprises a decoder, an encoder, and one or more patterns of crisscrossed interconnect lines. The decoder generates an enable signal for one of the decoder outputs by decoding one or more of the plurality of address symbols, while the encoder generates an output word based on the enable signal. The patterns of crisscrossed interconnect lines connect each of the decoder outputs to an encoder input. To reduce the size of the memory, some aspects of the present invention form the patterns of crisscrossed interconnection lines using one or more planar layers of conductor tracks vertically interleaved with isolating material to utilize the vertical dimension of the memory.
[0015] One exemplary use for this memory allows compressing memory size for storing values of an irregular function, or even storing random values, such as computer program instructions. In this case, the inventive algorithm operates on the function or data values in a sorted numerical order, which can be achieved by permuting address lines on the chip in a fixed pattern. The compression procedures described for regular functions can then be used to replace certain absolute data values with their deltas relative to the closest absolute data value stored anywhere, using fewer bits to store the deltas than to store absolute data values. Where two or more adjacent values are identical, they may be compressed to one, and the corresponding address lines merged using an OR gate input. Each OR gate input requires one transistor, and is thus equivalent to a memory bit in terms of silicon area occupied.
[0016] Reconstruction of an addressed value that has been compressed using an algorithm of order M comprises reading a word of length L2 bits whenever one of M adjacent address lines is activated. Then, its constituent parts comprising a base value, first order and higher differences are combined according to which of the address lines is active. Each group of M address lines may be combined using an M-line to log 2 (M)-line priority encoder to obtain log 2 (M) bits for systematically enabling reconstructive combinatory logic.
[0017] Using the invention, ROM silicon area can be reduced typically by a factor between 2 and 5 depending on the order of the algorithm and the amount of reconstructive combinatorial logic used. Bit-exact reconstruction always occurs, as is of course required when the compressed data is a computer program.
[0018] In a second aspect of an exemplary memory implementation, compression of random ROM contents is achieved by sorting the data into numerical order by permuting address lines. Storing the same number of bits of information with fewer actual bit elements in the ROM than information bits is possible because information is effectively stored within the permutation pattern. Because it is possible to accommodate on a chip very many layers of interconnection patterns separated by insulating layers, a large number of different permutation patterns of address lines may be fabricated, each containing information, thereby utilizing the vertical dimension to store an increased amount of information.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] FIG. 1 illustrates a mask programmed Read Only Memory (ROM).
[0020] FIG. 2 illustrates a plot of one exemplary regular function.
[0021] FIG. 3 illustrates one exemplary compression algorithm.
[0022] FIG. 4 illustrates exemplary reconstruction logic.
[0023] FIG. 5 illustrates a plot comparison between a true monotonic function and an exponential approximation.
[0024] FIGS. 6A-6D illustrate one exemplary process for eliminating a first layer of a Butterfly circuit for reconstructing stored data.
[0025] FIG. 7 illustrates a conventional MOS transistor.
[0026] FIG. 8 illustrates the construction of one exemplary memory circuit.
[0027] FIGS. 9A and 9B illustrate one exemplary row address decoder.
[0028] FIG. 10 illustrates one exemplary process for arranging stored data in a sorted order.
[0029] FIG. 11 illustrates one exemplary implementation for a memory using first-order compression of random data.
[0030] FIGS. 12 a - 12 C illustrate one exemplary implementation for address decoding.
[0031] FIG. 13 illustrates one exemplary priority encoder.
[0032] FIGS. 14A and 14B compare exemplary encoder and decoder combinations.
DETAILED DESCRIPTION
[0033] Firstly, an exemplary application of the invention will be described in which a look-up table is required for values of a regular function, e.g., a monotonically increasing function, desired for a particular computation. Equation (1) represents the exemplary function as:
F a ( x )=log a (1 +a −x ), (1)
where “a” is the base of the logarithms. This function is encountered in logarithmic arithmetic as described in U.S. patent applications Ser. No. ______ (Attorney Docket Numbers 4015-5281 and 4015-5287), which are incorporated herein by reference.
[0034] A plot of this function for base-2 is shown in FIG. 2 , for values of x between 0 and 16383 divided by 512, i.e., values of x with nine bits to the right of the binary point and 5 bits to the left of the point. The function is plotted versus the complement of 512×, denoted by {overscore (X)} M , which ranges from 0 to 32 and gives a monotonically increasing function value as the argument {overscore (X)} M is increased. The desire is to provide fast access to the function value with an accuracy of 23 binary places, for any of given x value from the 16384 possible discrete tabular points. Alternatively base-e may be used, in which case similar accuracy is achieved with 24 binary places.
[0035] The uncompressed look-up table for the latter would comprise 16384, 24-bit words, a total of 393216 bits. The values of the words should be rounded to the nearest LSB, a fact which will have a significance described later. However, whatever those values are, any compression and decompression algorithms applied to these look-up table values are required to reproduce the desired rounded values in a bit-exact manner.
[0036] For values of x greater than 17.32, the function is zero to 24-bit accuracy in the base-e case, and is zero in the base-2 case when x>24. This may be taken as F(x)=0, for x>24, i.e., x>11xxx.xxxxxxxxx or {overscore (X)} M <00xxxxxxxxxxxx; therefore values are only needed for {overscore (X)} M >00111111111=4095. This is particular to the exemplary function however, so will not be dwelt on here; rather, the provision of all 16384 values will be considered.
[0037] The difference between successive values for only 1 least significant bit difference in the argument {overscore (X)} M is obviously much smaller than the function itself, and so can be represented by fewer bits. This observation is true for any smooth function. Therefore, a first order compression algorithm comprises storing 24-bit values only for even address values of {overscore (X)} M , and in an odd address, storing the delta-value from the previous even value.
[0038] Direct computation for the exemplary function shows that the highest delta encountered is 16376 (times 2 −24 ), which can be accommodated within a 14-bit word. Therefore, the ROM can be reconfigured as 8192 words of 24 bits and 8192 words of 14 bits. Only the 24-bit value is required for an even address {overscore (X)} M , and both the 24-bit and the 14-bit value are required to be read and added for an odd address {overscore (X)} M . The ROM has thus been compressed from 16384×24=393216 bits to 8192×(24+14)=311296 bits, a saving of 21%, or a compression to 79% of the original size.
[0039] A second order algorithm can be derived by applying the process of replacing pairs of adjacent values by a value and a delta-value to the first array of 8192 24-bit values and separately to the second array of 8192 14-bit delta-values. The first application yields delta-values two apart in the original function, which are roughly double the single-spaced deltas, so requiring 15-bits of storage; the second application of the algorithm to the array of 14-bit first-order deltas yields second-order deltas, which theoretically should be in the range 0 to 31, requiring 5 bits. Due to the above mentioned rounding of the function to the nearest 24-bit word however, the range of the second-order deltas increases to −1 minimum to 33 maximum, requiring 6 bits of storage. This arises because one value may be rounded down while the adjacent word is rounded up, so increasing (or decreasing) the delta by 1 or 2.
[0040] The ROM size has now been reduced to 4096 each of 24, 15, 14 and 6-bit values, a total of 4096×59=241664 bits, a saving of 39%, or a compression to 61% of the original size. Reconstruction of a desired value comprises addressing the 4096×59-bit ROM with the most significant 12 bits of {overscore (X)} M to obtain the four sub-words of length 24, 15, 14, and 6-bits respectively; then the least significant 2 bits of {overscore (X)} M are used to control reconstruction of the desired value from the four sub-words as follows:
[0041] Denoting the 24, 15, 14, and 6-bit values by F, D2, D1, and DD respectively, for {overscore (X)} M LSBs=00, the desired value is F
01 F + D1 10 F + D2 11 F + D1 + D2 + DD
Forming F+D1 requires a 14-bit adder; forming F+D2 requires a 15-bit adder, and forming D2+DD requires a 6-bit adder. Therefore, 35 bits of full adder cells are needed to reconstruct the desired value. In the case of the exemplary function, the DD range of −1 to +33 can be shifted to 0 to 34 by reducing the stored 15-bit D2 value by 1, and using the rule:
[0042] for {overscore (X)} M LSBs=00, the desired value is F
01 F + D1 10 F + D2 + 1 11 F + D1 + D2 + DD
Thus, the 6-bit adder adds either 1 or DD to D2 according to the LSB of {overscore (X)} M , and in general could add a value DD0 or DD1, to allow any range of DD from negative to positive to be accommodated.
[0043] FIG. 3 depicts this algorithm for compression by iterating the process of taking differences between adjacent values. The desired values to be stored are initially the 16384 24-bit values denoted by f0, f1, f2 . . . , f6 . . . and so on to f(16384). A first application of the process of taking differences leaves the even values unchanged but each odd value is replaced with the difference from the preceding even value. For example, f5 is replaced by d4=f5−f4. For the exemplary smooth function, the differences are computed to be at maximum 14-bit long values, which is 1024 times smaller than the original 24-bit values. With even smoother functions that are almost a straight line, one might expect the difference between two values separated by only 1/16384th of the range to be 1/16384 times smaller than the maximum original value and thus 14 bits shorted. In general, this shortening of the word length is bound to occur for any smooth function. Thus, in the second row the function values are represented by 8192 pairs of values, one being of 24-bits length and the other being of 14 bits length.
[0044] In the third row of FIG. 3 , the even values denoted by f0, f2, f4 . . . and the difference values denoted by d0, d2, d4 . . . are shown separated to illustrate applying the difference algorithm to the remaining f-values and separately to the d-values. The result shown in the 4 th row is that every 2 nd even value, i.e., every 4 th one of the original values, now remains unchanged as a 24-bit value, but the even values in between such as f2-f0 have become 15-bit differences. Every alternate d-value likewise remains an unchanged 14-bit value while those in between such as d6-d4 have been reduced to 6-bit second-order differences. Now the original 16384 24-bit values have been compressed to 4096 sets of values comprising a 24-bit, a 15-bit, a 14-bit and a 6-bit value.
[0045] The process may be iterated until the majority of the values are high order differences of only 2 or so bits length. These ultimate high order differences form a rather random pattern, due to the original 24-bit values having been rounded either up or down to the nearest 24 binary places. The total size of the memory reduces according to how many times the difference algorithm is iteratively applied.
[0046] FIG. 4 shows the reconstruction logic for a second-order difference compression algorithm. The original method of storing 16384, 24-bit words shown in the upper picture comprises a look up table to which a 14-bit address is applied. The lower picture depicts the second-order difference compression technique in which the look-up table has been reduced to 4096, 59-bit values. These are addressed using only the most significant 12 bits of the original 14-bit address, which effectively define a group of four values within which the target value lies. The 59 bits comprising a 24-bit absolute value, a 15-bit double-spaced difference, a 14-bit single-spaced difference and a 6-bit 2 nd order difference are applied to respective adders as shown. The first column of adders is enabled by the bit of second least significance to add the 15-bit difference to the 24-bit value and to add the 6-bit second order difference to the 14-bit difference if the bit is a ‘1’, else, if the enabling bit is a ‘0’, the 24 bit value is passed without adding the 15-bit value and the 14-bit value is passed without adding the 6-bit value. The adder of the second column adds the output of the first two adders if the least significant bit of the original 14-bit address is ‘1’, else it passes the 24-bit value unchanged. In this way, the two least significant bits of the original 14-bit address control which of the group of 4 values is generated.
[0047] Further savings may be made by noting that D2 is almost twice D1, therefore only the 15-bit D2 need be stored plus a correction to be applied to the 14-bit value INT(D2/2)=RightShift(D2) in order to obtain the bit exact value of D1. The correction is a second order difference represented by D1−(D2/2), which, by direct calculation is found to occupy the range −1 to 8, requiring 4 bits of storage. Then it may be further realized that this 2nd order difference is nearly equal to ¼ of the value DD. Therefore it may be replaced by the difference from DD/4, which by direct calculation has the range −1 to +1, requiring 2 bits of storage, and is effectively a 3 rd -order difference, which may be denoted DDD.
[0048] Thus to reproduce each of the 16384 24-bit function values bit-exact, the stored values comprise 4096 sets of four values as follows:
A 24-bit value: F(4i) A 15-bit value: D2(4i)=F(4i+2)−F(4i) A 6-bit value: DD(4i)=(F(4i+3)−F(4i+2))−(F(4i+1)−F(4i)) A 2-bit value: DDD(4i)=(INT(D2(4i)/2))−(F(4i+1)−F(4i))−INT(DD(4i)/4)
The four function values F(4i), F(4i+1), F(4i+2), F(4i+3) are then reconstructable bit-exactly from:
F(4i+1)=F(4i)+INT(D2(4i)/2)+INT(DD(4i)/4)−DDD(4i) F(4i+2)=F(4i)+D2(4i) F(4i+3)=F(4i)+INT(D2(4i)/2)+DD(4i)+INT(DD(4i)/4)−DDD(4i)
Groups of 4 originally 24-bit values have been replaced by a total of 47 bits instead of 96, a compression factor of slightly better than 2:1.
[0056] Vice versa alternatively, the 14-bit D1 only may be stored plus a correction to be applied to 2D1 to obtain D2. Thus, other arrangements are possible, such as storing
the 24-bit value F(4i) the 14-bit value D1=F(4i+1)−F(4i) the 6-bit value DD=(F(4i+3)−F(4i+2))−D1 the 3-bit value DDD=(F(4i+2)−F(4i))−(2D1+INT(DD/4))
which may lead to slightly simpler reconstruction. It will be appreciated that operations such as INT(DD/4) represent the trivial logical function of omitting to use two LSBs of DD.
[0061] Before computing a table showing compression achieved using algorithms of different order, a more systematic version of higher order compression will be developed based on a modified Walsh Transform. The Walsh Transform approach forms the sum and difference of pairs of adjacent values and replaces the original values with the sums and differences. For example, in a first iteration to compress data comprising f0, f1, f2, and f3, f0 is replaced with s0=f0+f1, f1 is replaced with f1−f0, f2 is replaced with s2=f2+f3, and f3 is replaced with d2=f3-f2. A circuit that computes the sum and difference of a pair of values is called a butterfly circuit.
[0062] All of the sums are arranged adjacently followed by all the differences. The differences as already seen will be shorter words than the sums. The process is then repeated on the block of sum values, and then separately on the block of difference values, each half the length of the original, to obtain a second order algorithm and so on for higher order algorithms. The highest order algorithm for 16384 values is 14. At that point the blocks have only one value each and thus cannot be compressed further. The 14th order algorithm is in fact a 16384-point Walsh Transform, and lower order algorithms stop at the intermediate stages of the full Walsh Transform. The sum and difference values associated with the final iteration are concatenated to form the final compressed values stored in memory. It will be appreciated that the final iteration may be any selected iteration, and therefore, is not required to be the 14 th iteration.
[0063] When forming the sum of two 24-bit values, the word length can increase by one bit. However, the sum and the difference always have the same least significant bit, which can therefore be discarded on one of them without losing information. By discarding it from the sum and using
INT ( f0 + f1 2 ) = RightShift ( f0 + f1 ) ( 2 )
instead, the sum is prevented from growing in length. Upon reconstruction, the difference is added to or subtracted from the sum and its LSB is used twice by feeding it into the carry/borrow input of the first adder/subtractor stage to replace the missing sum LSB. Mathematically, the modified transform butterfly can be written:
SUM( i )= INT (( F (2 i+ 1)+ F (2 i ))/2)
DIFF( i )= F (2 i+ 1)− F (2 i )
and reconstruction can be written as:
F (2 i+ 1)=SUM( i )+ INT (DIFF( i )/2)+AND(1,DIFF( i ))
F (2 i )=SUM( i )− INT (DIFF( i )/2)−AND(1,DIFF( i ))
The above is a modified version of the well-known “Butterfly” operations used in Walsh-Fourier transforms:
SUM( i )= F (2 i+ 1)+ F (2 i )
DIFF( i )= F (2 i+ 1)− F (2 i )
and its inverse:
F (2 i+ 1)=(SUM( i )+DIFF( i ))/2
F (2 i )=(SUM( i )−DIFF( i ))/2
[0064] A Fast, base-2, Pseudo-Walsh Transform (pseudo-FWT) may be constructed using the modified Butterfly described above to transform groups of two adjacent values to a value and a delta-value, or groups of 4 adjacent values to a value, two delta-values a 2nd-order delta-value, and so forth. This makes it a systematic process to explore the characteristics of and implement higher order algorithms. The FORTRAN code for an in-place Pseudo-Walsh transform is given below:
C F IS THE GROUP OF M VALUES TO BE PSEUDO-WALSH TRANSFORMED C AND N=LOG2(M) IS THE ORDER OF THE ALGORITHM
SUBROUTINE PSWLSH(F,M,N) INTEGER*4 F(*),SUM,DIFF N1=M/2 N2=1 DO 1 I=1,N L0=1 DO 2 J=1,N1 L=L0 DO 3 K=1,N2 SUM=(F(L+N2)+F(L))/2 DIFF=F(L+N2)−F(L) F(L+N2)=DIFF F(L)=SU M L=L+1 3 CONTINUE L0=L+N2 2 CONTINUE N1=N1/2 N2=2*N2 1 CONTINUE RETURN END
[0089] The following table shows the amount of data compression of the exemplary function achieved using different order pseudo-Walsh algorithms:
Order of Number of Total Total Number of Bits Algorithm Words Wordlength Base-e Base-2 0 16384 24 393216 376832 1 8192 38 311296 (319488) 294912 2 4096 59 241664 (258048) 221184 3 2048 93 190464 (215040) 169984 4 1024 147 150528 (182272) 135168 5 512 238 121856 (161792) 106496 6 256 381 97536 (142848) 89088 7 128 624 79072 (135424) 71680 8 64 1084 69376 59968 9 32 1947 62304 51136 10 16 3507 56112 45072 11 8 5738 45904 37096 12 4 10020 40080 30492 13 2 17782 35564 26296 14 1 32085 32085 23188
The bit count in parentheses is that obtained when a Walsh Transform using the standard Butterfly operation is used. The inferior compression of the standard Walsh Transform is partly due to growth of the word lengths of sum terms, and partly due to an amplification of the rounding errors in the original table values when higher-order differences are formed, which is less noticeable when the modified Butterfly is used and the LSBs of the sum terms are discarded. In both cases, bit-exact reconstruction of the original values is achieved when the appropriate inverse algorithm is applied. In the base-2 case, the function F a (x)=Log 2 (1+2 −x ) is computed to 23 binary places, and 24 places in the base-e case, which represent similar accuracies.
[0090] Thus, with the ultimate transform order of 14 operating on the whole array, the look-up table reduces to a single word 32085 (23188) bits wide, which is less than 2 bits per table value on average; yet each value can be reconstructed to 24-bit (23-bit) accuracy. A single word is no longer a table, and needs no address, since it will always be “read”, the values can just be hard-wired into the inputs of the reconstruction adders. However, 14 levels of reconstruction adders are required and the number of single-bit adder cells required is around 65000. Because an adder cell is larger than a memory bit, this does not represent the minimum silicon area. The minimum area is achieved at some compromise between the number of bits stored and the number of adder cells required for value reconstruction. Nevertheless it appears that a silicon area reduction factor of around 4 or 5 is entirely feasible.
[0091] It may also be concluded that there is shown above a method to build a machine that will compute any discrete value of a smooth function. The memory table has disappeared in the limit, being replaced with hard-wired inputs to the adder tree. This can lead to a further stage of simplification in which adder stages that add zero may be simplified to handle only carry propagation from the preceding stage, and likewise adders that always have a “1” on one of their inputs can be similarly simplified.
[0092] The pseudo-FWT table compression algorithm may also be applied to the 512-word table needed to store the value 2 −0.X 2 log e (2) when base-2 logs are used, and X 2 is 9 bits long. This function is an approximation to the above exemplary function which can suffice over a portion of the argument range. It is useful to use this approximation over the whole range and to store only corrections needed, which have a shorter word length.
[0093] Using base-2; the bit patterns for this base-2 exponential function repeat with a shift when the argument changes from 0.X 2 to 1.X 2 , 2.X 2 , etc., so only the bit patterns for the principal range denoted by 0.X 2 , where X 2 is a 9-bit value, need be synthesized. The following table gives the total number of bits required to be stored to synthesize the function, rounded to the nearest 23 bits after the binary point, for values of the argument X 2 from 0 to 511.
Total No. Order of Algorithm Number of Words Total Wordlength of Bits 0 512 23 11776 1 256 37 9472 2 128 57 7296 3 64 89 5696 4 32 139 4448 5 16 219 3504 6 8 358 2864 7 4 585 2340 8 2 974 1948 9 1 1608 1608
The final row constitutes a machine for computing the function without a memory, using only controlled adders with fixed, hardwired inputs.
[0094] In addition to the above bits, corrections to this exponential function are needed to obtain the values of F a (x)=Log 2 (1+2 −x ) or F s (x)=−Log 2 (1−2 −x ), which are used in logarithmic arithmetic for addition and subtraction in the log-domain.
[0095] The differences between the desired values of F a and F s and the exponential function are plotted for the base-2 case in FIG. 5 . These differences can be stored in a look-up table that occupies less space than the original functions, the chip area being indicated approximately by the triangular area under the curve to the bottom right. Furthermore, since the corrections also form a regular function, that table also can be compressed by the techniques described herein.
[0096] In a variation of the compression algorithm, the reconstruction adders may be largely eliminated. This is based on the realization that the sum of a given 24-bit value and a given 14-bit delta value always leads to the same 14 LSBs as a result. Therefore it is just as efficient to store the 14 LSBs of the pre-computed sum of the 24-bit and the 14-bit value, i.e., c0=f0+d0, in place of the 14-bit delta, i.e., d0. It is also necessary however to store an extra bit indicating whether the sum of the 14-bit delta to the 24-bit value caused a carry from the 14th bit to the 15 th bit. Thus by storing 15 bits instead of 14, the first 14 bits of the reconstruction adder can be eliminated. The 15 th bit is applied to a carry propagation circuit for the most significant 10 bits. A carry propagation circuit is simpler than full adder, and may be eliminated if there is a later stage of addition in the application into which the 15th bit could be inserted. This is explained with the aid of FIG. 6 . In effect, the least significant bits of a pair of original adjacent values are retained, but associated to a common most significant part. In addition, an extra bit indicates whether the most significant part has to be incremented when reconstructing the second value of the pair.
[0097] FIG. 6A shows a conventional butterfly circuit for adding or subtracting the same 14-bit value to/from the 24-bit value to produce one of two alternative values according to the SELECT control line. FIG. 6B shows that the butterfly circuit can be simplified into a 14-bit adder for adding or subtracting the 14-bit value to/from the 14 LSBs of the 24-bit value to produce one of two alternative 14 LSBs of the result, plus a carry or borrow bit from the add or subtract operation which is combined with the 10 MSBs of the 24 bit value to produce one of two alternative 10-bit MSB patterns. The MSB patterns may be the same if no borrow or carry is generated by the 14-bit add/subtractor. In FIG. 6C , the two alternative 14-bit results are simply pre-stored, that corresponding to the difference (subtract) operation is stored along with the 10 MSBs in place of the 24-bit value, while that corresponding to the sum result is stored in place of the 14-bit value. However, a 15 th bit is needed to indicate whether the 10 MSBs are the same or incremented by 1 for the sum case. The 15 th bit is always a zero in the difference case and is shown as an input to the selector alongside the 14 LSBs from the 24-bit word. If zeros are implemented in memory as the absence of a transistor, the column of zeros takes up no silicon area. The carry propagator is still needed in FIG. 6C to increment the 10 MSBs if necessary.
[0098] The selector in FIG. 6C does not need to be explicitly provided. It is inherent in memories that the address bits select one or other of a number of stored values. Therefore the two alternative 14 (or 15) bit patterns are simply selected by the select line, which is the least significant bit of the 14-bit address. The 10 MSBs are addressed by the 13 MSBs of the address. Thus, the memory comprises 8192 10-bit words and 16384 14/15-bit words, a total of 319488 bits, which is 8192 bits more for the benefit of eliminating a 14-bit adder. Finally, FIG. 6D shows the omission of the carry propagator by delaying incrementing the 10 MSBs with the carry bit and simply feeding forward the carry bit to be used at a convenient opportunity in a subsequent adder.
[0099] The division of the 24-bit word into a 10-bit part and a 14-bit part in FIG. 6 arises from the exemplary function exhibiting a delta between even and odd addressed values that is never more than a 14-bit value. The 10 MSBs are always the same or differing only by 1 between an even and adjacent odd-addressed value. Similarly, the difference between values 2 apart is never more than a 15-bit value, and the difference between values 4 apart is never more than a 16-bit value. Therefore, a group of 4 (or even 5) adjacent values have the same most significant 8 bits except for a possible increment of 1, while having different least significant 16-bit parts. Therefore, an alternative realization is to arrange the memory as 4096 8-bit values and 16384 17-bit values, the 17th bit indicating whether the 8 MSBs have to be incremented by 1 or not. This reduces the number of bits to 311296. A table showing the number of bits of memory for different splits is shown below.
Group Size No. of MSBs No. of LSBs (+1) Memory Bits 2 10 15 319488 4 8 17 311296 8 7 18 309248 16 6 19 317440 32 5 20 330240 64 4 21 345088
The table indicates there is an optimum split which minimizes the number of bits.
[0100] This process can now be iterated by recognizing that the LSB patterns within each group are monotonically increasing values. For example, in each group of 64 values in the last case, no two adjacent values can differ by more than a 14-bit value. Therefore these values can be divided into 32 groups of 2, storing for each pair 7 MSBs (which may have to be incremented by 1) and two alternative 14 or bit LSB patterns, the 15th bit indicating if the 7 MSBs should be incremented by 1.
[0101] The different ways to represent groups of 64 21-bit values is shown below, with the overall number of memory bits implied.
No. of Bits for Group Size No. of MSBs LSBs (+1) 64-group Total Memory 2 7 15 1184 304128 4 5 17 1168 300032 8 4 18 1184 304128
[0102] Repeating the procedure for the case of groups of 32 yields:
No. of Bits for Group Size No. of MSBs LSBs (+1) 32-group Total Memory 2 6 15 576 297472 4 4 17 576 297472 8 3 18 588 303616
[0103] For groups of 16, obtain:
No. of Bits for Group Size No. of MSBs LSBs (+1) 16-group Total Memory 2 5 15 280 292864 4 3 17 284 296960
For any given table of a regular function, it is possible to carry out the above trials and determine the method that will result in the minimum number of stored bits.
[0104] The above methods can be used not only for smooth functions, but also for piecewise smooth functions. For example, if groups of 32 values at a time are compressed using any of the above techniques, it is only necessary for the values within each group of 32 to represent a smooth function, i.e., a continuous function. Discontinuities between different groups are then of no significance.
[0105] To explain how the technique can be applied to more random data, the construction of a typical MOS ROM is first described. FIG. 7 shows the construction of a MOS transistor. A conducting gate electrode is made of a conducting material with a high melting point so as to withstand processing temperatures, and is separated from the silicon substrate by a thin insulating layer, generally of silicon dioxide. The gate and its underlying oxide insulation are generally produced by covering the whole substrate with gate structure first and then etching away except where gates are desired. Then drain and source electrodes are formed by implanting impurities on either side of the gate, the gate acting as its own mask to ensure that drain and source adjoin the gate exactly. The implanted impurities have to be allowed to integrate with the silicon substrate crystal structure by raising the temperature to just under the melting point of silicon. Having formed MOS transistors in this way, they may be interconnected by depositing aluminum interconnecting tracks.
[0106] FIG. 8 shows a ROM constructed in this way. Alternating stripes of source and drain diffusion form a multitude of transistors with their sources and drains paralleled. The transistors are located where the gate structures have not been etched away. A transistor is placed where a binary 1 is desired to be stored, and no transistor is placed where a binary 0 is to be stored. Actually in FIG. 8 , a transistor is shown as comprising a gate from the source line above the drain line and a gate from the source line below the drain line. Both are enabled by the same gate signal and thus are in effect two transistors in parallel. The number of separate drain lines corresponds to the number of bits in a word. All of the source lines for the same word are connected at the left hand side to a word row enable signal, which is pulled to ground to read a word in that row.
[0107] Different columns of transistors correspond to different words in the row. An address decoder accepts a binary address input and puts an enable signal on all the gates in one column, thus enabling all the bits of a particular word to the drain lines. The drain line is pulled down by a turned on transistor if the word contains a zero in that position, or else is not pulled down if a transistor is absent, corresponding to a 0 in the word.
[0108] Multiple rows of words can be constructed and the address lines run top to bottom through all rows. The source enable lines for each word-row are connected to a second row-address decoder and the whole address is then a combination of the column address and the row address. A suitable row-address decoder that pulls down the source lines of the enable word-row is shown in FIGS. 9A and 9B .
[0109] As shown in FIG. 9A , a cascadable building block comprises two MOS transistors with their sources commoned to the “cascoding input” C. An address line is connected to the gate of one transistor and its drain develops a complementary address signal, which is connected to the gate of the other transistor. The result is that either one transistor or the other conducts between source and drain depending on whether the address line is high or low. A cascade of this building block is shown in FIG. 9B , in which the drain connections DR 1 and DR 2 of a first device controlled by address bit A 1 are connected to the source connections of two identical building blocks higher in the chain which are both controlled by address bit A 2 . Their drain connections are in turn connected to pairs of building blocks that are all controlled by address bit A 3 to present 8 drain connections, and so forth. In this way, an N-bit address bit pattern is decoded by the binary tree of building blocks to produce a conducting path from one of 2 N final drain connections to the first source connection annotated “Chip Enable”.
[0110] Pulling down the chip enable line then pulls down one of the drain connections corresponding to the enabled conducting path, which in turn pulls down one of the word-row source lines, which in turn pulls down drain lines for that word row corresponding to which word transistors have been turned on by the column address. A sensing amplifier (not shown) detects which bit lines are being allowed to pull current from the supply and creates the output bit pattern corresponding to the addressed word. The sensing amplifier compensates for the loss through the long chain of transistors and provides a buffered logic level output to the processor external to the memory.
[0111] FIG. 10 shows how a memory containing random values can be arranged in order of numerical value. The words are simply sorted and arranged in numerical order, while remaining connected to the same output line of the address decoder. This requires that the decoded address lines be crisscrossed as shown, which can be accomplished with a suitable multi-layer interconnection pattern. The address lines can be re-arranged in a different crisscross pattern for connection to the next row of words, which will likely be sorted in a totally different order. This in itself does not achieve compression, but is merely illustrative of the possibility to arrange even random data on a chip in a monotonically increasing order of numerical value while still reading out the correct value associated to each address.
[0112] FIG. 11 illustrates the implementation of a memory for first-order compression of random data using a decoder, crisscross line pattern, and an encoder. Every alternate full word, in value-sorted order, has been removed compared with FIG. 10 . The preceding word to the removed word is now addressed by its own address as well as the address of the omitted word that was adjacent to it by including an OR gate to OR the two addresses. The address line of the omitted word now enables a shortened delta-word, which is to be added to the preceding word by the reconstruction logic in order to recreate the omitted word. The number of bits of memory has been reduced to a full word and a delta word for every pair of original full words at the cost of a two input OR gate per pair. A two-input OR-gate is at maximum 4 transistors, which can be counted as four bits. This should be added to the delta-word length in estimating the amount of silicon area saved.
[0113] The address-line crisscross pattern also requires chip area. By relocating the OR gates below the full words, the crisscross connection pattern may run over the top of the area occupied by the full-words using a suitable number of metallization layers insulated or mutually isolated from each other. Such layers may be fabricated using photo-lithographic techniques. For the purposes of this invention it is assumed that an essentially unlimited number of metallization layers can be used, and that insulative layers isolate the crisscrossed interconnection lines and/or patterns of crisscrossed interconnection lines from unwanted contact. Indeed, using layer upon layer of interconnect patterns, in order to store more data using the same chip area, exploits the vertical dimension.
[0114] One has to be careful in extending the concept of higher order difference algorithms to random data, as differences of greater than first order may show no meaningful regularity. Instead, choosing one full word as a base value for a group of words, and replacing the other words in the group by their deltas from the base value can improve the efficiency of compression. For example, a group of four values f0, f1, f2, and f3 can be replaced by f0, d1=f1−f0, d2=f2−f0, and d3=f3−f0. The logical OR of 4 addresses must then address the value of f0. A four input gate is a maximum of 8 transistors. The silicon area occupied by this 4-input OR gate is the cost for the savings of reducing 3 full-words f1, f2, and f3 to three delta-words d1, d2, and d3. The 4-input OR gate is only twice as complex as the 2-input OR-gate but the memory reduction is now approximately 3 times greater. Therefore the overhead of the OR-gate has reduced in comparison to the savings achieved. Wherever two data values to be stored are identical and thus appear next to one another in value sorted order, they are replaced by a single value and no delta need be stored. Then the address line corresponding to the zero delta is not needed, and the OR of the two address lines to the single stored value may be absorbed into the last stage of address decoding by using an AND-OR gate as shown in FIG. 12 .
[0115] FIG. 12A shows two decoders of the FIG. 9 type for decoding, for example, 8 address bits to one 256 address lines. Because FIG. 9 has open-drain outputs, pull-up transistors (or resistors) have to be added to reset the outputs to a known state between memory reads. The 256-lines of one decoder (A 0 . . . . A 255 ) are then crossed over the 256 lines (B 0 -B 255 ) of the other to give 65536 crossing points. When an individual one of the 65536 lines must be decoded, a 2-input AND gate is placed at that junction, as shown in FIG. 12B , giving an address decoder complexity of 4 transistors per output line, as the number of transistors in the 8*256 line decoders is negligible in comparison. When however only the OR of two addresses is needed, FIG. 12C shows how the 8 transistors of two AND gates can be reconnected to form an AND-OR using no extra transistors.
[0116] Analyzing some typical DSP programs used in mobile devices made an estimate of the savings possible using the above technique. A first program comprising 8464 16-bit instructions was determined to comprise only 911 different 16-bit values. Clearly many values are repeated multiple times and the above technique of storing these only once and using AND-OR address decoding can save a factor of 9 approximately in chip area without needing to use any delta values. A second program of 2296 words was found to comprise only 567 different 16-bit values, also allowing a significant compression factor. The combined programs compress from 10760 words to 1397 words. The 4-transistors per address used in AND-OR address decoding were required in the conventional memory's address decoder, and therefore do not add complexity. A more accurate estimate of the size reduction is to add the 4-transistors per address of the address decoder to the 16 transistors per word of the memory array to obtain 20 transistors per word total for the conventional memory, which reduces to 4+16/9 transistors, which represents approximately a factor of 3 reduction.
[0117] When the number of words to be stored exceeds the number of possible values, for example storing 1 megaword of 16-bit values, it is evident that it is never necessary to store move than 65536 values, using AND-OR address decoding to combine all addresses at which the same word is to be stored to enable that particular 16-bit word. A memory of this type benefits from the use of more overlapping interconnecting layers to handle the complex interconnection pattern of AND-OR addressing. The technique is thus a method of using the vertical dimension on chips (more interconnecting layers) to realize more efficient memories.
[0118] In the latter case, the 65536 possible words do not even need to be stored. Having AND-ORed the appropriate address lines into one of 65336 lines that are required to cause an output of values from 0 to 65535 to be generated, a device called a priority encoder can be used as a 65536:16 line encoder, which is the inverse function of a 16:65536 line address decoder. A priority encoder can be constructed with at most 6 transistors per input, which is less than the 16-bits per word otherwise needed. A priority encoder is shown in FIG. 13 .
[0119] A set of N inputs numbered 0 to N−1 is divided into a first half 0 to N/2−1 and a second half N/2 to N−1. Pairs of corresponding lines are selected from the first and second halves, for example lines 0 and N/2 as shown, to be ORed together. The NOR gate gives a logic ‘0’ out if either of the inputs are a 1. The N-type transistor conducts if the lower input was a 1 and connects the upper input, which must be a 0, to output B. The P-type transistor conducts if either input was a 1, and connects the upper input to the output B if the upper input was a 1. Therefore, output B has the polarity of the upper input if either of the inputs was a 1, else output B is open circuit. All output B's are paralleled forming a wired OR, giving a 1 out if the active input line lay in the upper half of the inputs, else a ‘0’ is output. This is the most significant bit of the desired encoding. The process is then repeated for the N/2 outputs A 0 to A(N/2-1) to produce the second most significant output bit of the desired encoding, and so forth. The number of stages required to fully encode the input lines is thus N/2+N/4+N/8 . . . =N−1, and each stage comprises 6 transistors (the 4-Transistor NOR gate plus a P and an N type transistor).
[0120] The combination of an address decoder and its inverse, a priority encoder, just reproduces the input, as shown in FIG. 14 . If the lines are crossed however, any 1:1 mapping (also known as a Substitution box or S-box, or an information lossless coding) is produced. If some addresses are AND-ORed, implying that some output values are missing, a many:one mapping or information lossy coding is produced. Thus any read only memory having an output word length equal to the address word length can be produced in this way. The information is evidently stored in the address line crisscross or permutation pattern, as that is the only difference between FIGS. 14A and 14B . Using an estimated 4 transistors per line in the address decoder and 6 in the priority encoder shows a saving for memory sizes above 1024 10-bit words. However, using multiple interconnecting layers, several different interconnecting patterns can be produced, all sharing the same priority encoder and address decoder, providing a method of selecting the desired interconnecting pattern. A series pass switch per line, comprised of a P and an N type transistor in parallel as shown in FIG. 13 may be used for this. Thus a number M of interconnecting patterns may be selected and a memory of size M.2 N N-bit words may be created using 2+10/M transistors per word, showing an increasing efficiency as the number of layers is increased. It is possible that single-transistor pass switches could be used, for example by creating a power supply of −V t (for a P-type switch) or V cc +V t (for an N-type switch) to ensure that the switch conducts for both a logic 1 and logic 0 level.
[0121] To recap, it has been shown that tables of stored data that represent monotonic functions can be compressed by storing only one base value per group of numerically adjacent values, plus the deltas from the base value for the other values in the group. Alternatively, groups of values may be transformed using a Walsh Transform using a modified Butterfly operation. The limiting case of the latter results in the ability to synthesize any monotonic function with an array of adders with fixed inputs because the memory table has disappeared. An alternative to storing deltas was disclosed to comprise storing the LSB part of the pre-computed result of adding the delta, plus an extra bit to indicate if a carry to the MS part is required, thus eliminating the majority of the reconstruction adders. The technique was extended to piecewise monotonic functions, where the function is monotonic for each compression group. The technique was then extended to random data such as a computer program, by imagining the data to be first sorted in numerical order by permuting the address lines.
[0122] When any Delta is zero, it need not be stored, nor an address line generated to address it, thus allowing simplification of the OR-ing of addresses needed for the base word. Analysis of a typical DSP program showed that the majority of the compression could be achieved using this technique alone. Moreover, all possible output values can be produced by a priority encoder using 6 transistors per address line, instead of storing them, which is more efficient when the number of possible output values is greater than 64. Information then resides in the interconnect pattern that connects the address decoder to the priority encoder. Finally, it is shown that a memory can store several random sets of data by employing the vertical dimension to construct several such interconnect patterns, and selecting the desired pattern using pass switches for a reduction in the number of transistors used per word, ultimately to 1 or 2 transistors per word.
[0123] The present invention may, of course, be carried out in other ways than those specifically set forth herein without departing from essential characteristics of the invention. The present embodiments are to be considered in all respects as illustrative and not restrictive, and all changes coming within the meaning and equivalency range of the appended claims are intended to be embraced therein. | Exemplary embodiments of the present invention comprise a method for compressing data for storage in memory. According to one embodiment, the method forms a set of values based on a monotonically ordered series of look-up table values. For one or more paired values in the set, the exemplary method generates a difference of the values in the pair. After replacing one of the values in the pair with a value based on the differences to modify the set, the exemplary method stores final values based on the modified set in memory. The present invention also comprises memory for storing the look-up table values. One exemplary memory comprises a decoder, an encoder, and one or more patterns of crisscrossed interconnect lines that interconnect the encoder with the decoder. The patterns of crisscrossed interconnection lines may be implemented on one or more planar layers of conductor tracks vertically interleaved with isolating material. | 7 |
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