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CROSS REFERENCE TO RELATED UNITED STATES APPLICATIONS
This application claims the benefit of “SYSTEM AND METHOD FOR ENERGY CONSERVING ROOFING”, U.S. Provisional Patent Application No. 60/324,409, filed on Sep. 24, 2001 by Azari and Bierman, the contents of which are incorporated herein by reference.
FIELD OF THE INVENTION
This invention is directed to a roofing system that can change its energy reflectance based upon the outside temperature, or a manual control.
BACKGROUND OF THE INVENTION
White pigment on roof surfaces has been shown to generate interior temperatures that are as low as fourteen degrees (Fahrenheit) below temperatures sampled in buildings with dark roofs; it also has been shown to lower roof temperatures by up to seventy degrees (Fahrenheit), thereby extending the surface's useful life. Such white roofs are called “cool roofs”. While having a cool roof is beneficial to buildings during warm weather, it has obvious repercussions during cooler weather.
In a 1998 study, scientists at Lawrence Berkeley Laboratory in Berkeley, Calif., concluded that residents and businesses in the New York City area could cut their summertime air-conditioning costs by $22 million by swapping dark roofs with more reflective ones. Outdoor summer temperatures could also drop a couple of degrees. See, e.g., “Cooling Energy Savings Potential of Light-Colored Roofs for Residential and Commercial Buildings in 11 U.S. Metropolitan Areas”, S. Konopacki, H. Akbari, M. Pommerantz, S. Gabersek, and L. Gartland, Laurence Berkeley Laboratory, Environmental Energy Technologies Division Report, May. 1997; “Simulated Impact of Roof Surface Solar Absorptance, Attic, and Duct Insulation on Cooling and Heating Energy Use in Single-Family New Residential Buildings”, S. Konopacki and H. Akbari, Laurence Berkeley Laboratory, Environmental Energy Technologies Division Report, October 1998. On the other hand, the reflective roofs would raise heating bills by $6 million in winter. Hot roofs are preferable in wintertime. See “Scientists Watch Cities Make Their Own Weather”, Kenneth Chang, New York Times, Aug. 15 th , 2000. As an example, FIG. 1 depicts an infra-red (IR) photo of a roof, of which the top part is coated and the bottom part is not. The coloration of the photo indicate that white coating reduced the roof temperature by about 40° C. (70° F.). See “Projects of the Heat Island Group: Demonstration of Energy Savings of Cool Roofs”, http://eetd.lbl.gov/HeatIsland/PROJECTS/DEMO/.
While the notion of enjoying the benefits of a white roof (or “cool roof”) has been accepted and applied for many years, there is no technology in the market that allows buildings to capture the value of cool roofs during warm weather without losing value during colder weather. Thus, within the American market, cool roofs are widely used throughout regions that do not experience dramatic variances in temperature, such as the extreme southern regions of the United States. However, most areas of the country cannot afford to take advantage of cool roofs because of the consequences that would be incurred during colder months. Consequently, there is a need for a roofing system that can change its energy reflectance based on the outdoor temperature. For example, FIG. 2 depicts a graph showing the potential net energy savings from changing roof reflectivity. Savings are measured in dollars. Note that the net savings are the savings of cooling energy use less the penalties of heating energy use.
SUMMARY OF THE INVENTION
The answer to this problem is to have a roof that changes color to complement the outdoor temperature. A roof with this property shall be referred to herein as a thermochromic roof, or more generally, as a thermomorphic roof, as there are several mechanisms that can cause a material to change color or reflectance based on temperature. A thermomorphic roofing material would do away with heat loss in the winter, making a reflective roof a more economically feasible option throughout the United States.
In one embodiment, a thermomorphic coating can be applied to existing roofing surfaces. The coating can have a white or light color during warm weather and a black or dark color in cooler weather.
Thermnomorphic materials have been used for quite some time. They are relatively cheap, and manufacturing facilities are abundant. They are processed to alternate between virtually any (two) colors, and can be triggered at almost any “target” temperature. The transition is achieved by changing the exact chemical make up of the thermomorphic portion of the pigment. The pigment can be manufactured in microencapsulated form.
The material being encapsulated dictates the exact method of microencapsulation because microencapsulation serves as a barrier between the thermomorphic system and any chemicals around it, such as the paint base. If the thermomorphic system is intrinsically thermochromic or photochromic, as explained below, all it needs to be encapsulated with is a buffer. However, if the encapsulated material is ionochromic, that is, a material that changes color upon interaction with an ionic species, as explained herein below, then it needs to be mixed in the microcapsule with a color developer, such as a phenolic material, and a non-polar co-solvent medium in addition to the color former. The co-solvent medium is typically a low melting point, long chain alkyl compound. The microencapsulated pigment is then added to a chosen medium—such as a coating—and a thermomorphic product is born.
A thermomorphic coating can be calibrated at the site of manufacture for each target climate. Each calibration would change color according at a predetermined optimal temperature. The fine-tuning of such a calibration is done through the choice of color developer and co-solvent used in microencapsulation. The temperature at which the material will change color is largely set by the melting point of the co-solvent. This is recognized and trusted process that is adopted by a number of existing manufacturers in different industries with different applications.
The thermomorphic material can be added, in microencapsulated form, to spray on roofing. In this manner the entire roof, in one application, with no extra work, can become thermomorphic.
Alternatively, shingles can be factory coated with a thermomorphic coating for use on new residential, steep slope roofs, or anywhere a shingle is required. The thermomorphic shingle can be an asphalt shingle, a plastic shingle, or just about any kind of shingle that can be painted. The shingle can be coated at the factory with thermochromic paint, and can be applied at the construction site exactly like a regular shingle. There are a whole host of materials that can be coated in the factory with thermomorphic paint for use in building construction. Shingles are merely the first.
A third embodiment of the present invention involves an electrophoretic panel. Electrophoretic panels can provide a roofing material that has the same energy saving effects as the thermomorphic coated materials, but without the added cost of an overlay (coating). Electrophoretic sheets can be laid down as the top layer of the roofing system. The electrophoretic sheets are comprised of two pieces of electrically conductive plastic with a clear colloid between them. Those plastic sheets make electrophoretic sheets very durable and water resistant. The sheets can be cut to any size, including the size of a shingle.
Electrophoretic panels can facilitate manual control of a roof's color transition from dark to light or vice-versa. Alternatively, if connected to a thermostat, the panels can become part of a building's existing heating/air-conditioning scheme. This can translate into even more substantial savings in energy costs. Electrophoretic sheets require very little power to prompt the transition, and do not demand any power to maintain it. Electrophoretic sheets can be as automatic as thermochromic coating, but retain the ability to be overridden manually.
Unlike thermomorphically coated materials, electrophoretic sheets do not need a specific pre-determined temperature at which the color change is set to occur. Thus, there is no need to tailor the product to different climates at the time of manufacture.
Each embodiment of the invention will yield lower energy expenditure in both cold and hot weather. In addition to saving energy, the roofing system of the present invention will provide improved comfort, will lower costs, and will reduce air pollution.
Comparison studies have shown that cool roofs are an effective means of lowering roof maintenance costs. See a “Cool Coatings Heat Up Savings”, Lisa M. Gartland, Maintenance Solutions, January 1999. These findings provide evidence that cool roofs extend the usable life of a roof surface. For example, after ten years, a conventional roof typically requires a new layer of roofing while a thermochromically coated roof will likely require only a new application of coating. Moreover, like prevailing cool coating alternatives, thermochromic paint can be expected to slow the aging process of underlying roofing materials.
Similarly, by increasing the useful life of roofing materials, thermochromic roofs can reduce the amount of roofing waste generated. See id. Currently, there are approximately 11 million tons of asphalt roofing waste going into landfills every year. Id.
Finally, the thermomorphic products can reduce air pollution. First, because less cooling/heating will be needed for a given structure, fewer emissions will be produced in energy generation. Second, cooler surfaces transfer less heat to the air, keeping urban temperatures lower, in turn reducing smog formation. (S. Konopacki et. al., Laurence Berkeley Laboratory, Environmental Energy Technologies Division Report, May 1997 and October 1998)
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows an infra-red photo of a roof.
FIG. 2 depicts a graph showing the potential net energy savings from changing roof reflectivity.
FIG. 3 depicts the structure of a spirooxazine.
FIG. 4 depicts the structure of a typical stereoisomer.
FIG. 5 depicts the structure of a polythiophene.
FIG. 6 depicts the structure of a spironaphthoxazine.
FIG. 7 depicts the structure of a benzopyran.
FIG. 8 depicts the structure of a naphthopyran.
FIG. 9 depicts the structure of a fulgide.
FIG. 10 depicts the structure of a diarylethene.
FIG. 11 depicts the structure of a diheteroarylethene.
FIG. 12A shows a synthetic route to symmetrical and non-symmetrical dithiophenylperflurorocyclopentenes; FIGS. 12B and 12C depict the structure of respective dithiophenylperfluorocyclopentenes.
FIG. 13 depicts the structure of a crystal violet lactone.
FIG. 14 depicts the structure of an azo dye.
FIG. 15 depicts a microencapsulated thermochromic system.
FIG. 16 depicts the structure of a phthalein
FIGS. 17 and 18 depict variations in the structure of a flourene.
FIGS. 19 and 20 depict variations in the structure of a flouran.
FIGS. 21 and 22 depict structural variations of a diarylphthalide.
FIGS. 23 and 24 depict structural variations of a lactam.
FIG. 25 depicts the general structure of a sulfone.
FIG. 26 depicts an electric field between two charged plates
FIG. 27 depicts an example of an electrophoretic cell.
DETAILED DESCRIPTION OF THE INVENTION
1. Thermochromic Coatings
A thermochromic coating is a coating that changes color in response to heat. At a specific temperature point a thermochromic material will change its color, that is, the wavelengths of light that it absorbs and reflects. The actual mechanism used to change color varies depending upon the material in question. There are several different methods for achieving the desired thermochromic effect. Each method has specific environmental and application specifications and involves different materials.
Intrinsically Thermochromic Materials
Some materials are intrinsically thermochromic and are therefore very easy to use in a coating. Cholesteric liquid crystals, a supra-molecular system, are among the most commonly used intrinsically thermochromic materials because of their ability to change color at low temperatures.
All that would be required is to add such materials to a carrier that does not chemically interact with them, thus preserving their thermochromic properties. Any colorless paint or coating suitable for application to buildings or roofs can serve as such a carrier. Alternatively, they can be microencapsulated so that there is a buffer between the thermochromic material and the paint/coating. The transition temperature at which an intrinsically thermochromic material changes state from reflecting to absorbing is an intrinsic property of the compound, and is not altered by mixing with the carrier material. A short list of some intrinsically thermochromic material families and some specific materials, listed below family names, is as follows:
a. Spirooxazines (see FIG. 3 ) b. Compounds exhibiting stereoisomerism (see FIG. 4 )
i. Biathrylidenes
1. Bianthrones
ii. Bithioanthylidene iii. Mixed Bianthrylidenes
1. xanthylideneanthrone
iv. dixanthylidenes
c. Polythiophenes (see FIG. 5 ) d. Polysilanes e. Polydiacetylene f. Macromolecular Systems
i. Polythiophenes ii. Polysilanes iii. polydiacetylene
Photochromic Materials
Photochromism is a chemical process in which a compound undergoes a reversible change between two states having separate absorption spectra, i.e. different colors. The change in one direction occurs under the influence of electromagnetic radiation, usually ultraviolet (UV) radiation, and in the other direction by altering or removing the light source or alternatively by thermal means. Photochromic materials can be used for creating a coating that will change color in the desired thermochromic fashion, but some small technical work-a-rounds must be used. One type of workaround involves using a heat sensitive UV blocker. Such a blocker loses its effectiveness as becomes hotter, thus blocking less UV radiation. A second mechanism involves a material that darkens upon exposure to UV radiation. After this material heats up, it lightens in color. When the temperature drops again, the UV blocker becomes active and the ensuing lack of UV radiation causes the photochromic material to return to a dark colored state so that it begins absorbing heat. There are many photochromic materials, almost all of which can be modified in one way or another to exhibit the properties needed for this application. For instance, one group of chemicals known as spiroindolinonaphthoxazines change color upon exposure to UV light, which happens each and every time the sun rises. This group of chemicals changes back on either the removal of the UV light source (sundown) or heating to change point (hot summer day) and in that manner can be used as an additive to paint or coatings for use as a thermochromic coating on a roof. A short sampling of photochromic material families, along with a few example materials, is as follows:
a) Spironaphthoxazines (see FIG. 6 )
a. Spiroindolinonaphthoxazines b. Spiroindolinopyridobenzoxazines
b) Benzopyrans (see FIG. 7 ) c) Naphthopyrans (see FIG. 8 )
a. Diarylnaphthopyrans
d) Fulgides (see FIG. 9 ) e) Diarylethenes (see FIG. 10 )
a. Diheteroarylethenes (see FIG. 11 )
f) Dihydroindolizines g) Dithiophenylperfluorocyclopentenes (see FIG. 12 ) h) Spirobenzopyrans
Ioniochromic Materials
Ionochromism is the name applied to the phenomenon of a color change associated with the interaction of compounds or materials with an ionic species. Usually that species is a solvated hydrogen ion. Other commonly used ions are metal ions and omnium cations such as tertiary ammonium and phosphonium.
Ionochromic materials are very important for the purpose of creating thermochromic coatings. This is because the color change is controlled by the presence or absence of ions that can be provided by raising or lowering the pH of the environment. Control of the local pH can be obtained through the use of any number of materials that melt at the required temperature, releasing ions into the local environment. A good example of this is crystal violet lactone.
Obtaining thermochromic properties from crystal violet lactone requires the combined use of three components: (1) a color former, (2) an acidic color developer, such as a phenolic material, and (3) a non-polar co-solvent medium, such as a long-chain alkyl compound, that will control the interaction between the first two ingredients of the formulation. When the components are heated and mixed together in the correct proportions so that the color former and developer are dissolved in the co-solvent and the solution is then cooled, the solid composite formed is intensely colored. When that material is heated past the melting point of the co-solvent the pH level is changed and the crystal violet lactone goes to a ring closed position. This makes the material colorless. FIG. 13 depicts the structure of crystal violet lactone, and shows that acid is used to change the pH, and cause the change in color.
This formula will be added, in microencapsulated form, to off-the-shelf paint and coating products, rendering them “thermochromic”. The material will be calibrated at the site of manufacture for each climate individually and, for each calibration, will change color according to a predetermined temperature. The transition temperature at which the ionochromic material changes from absorbing to reflecting is determined by the melting point of the co-solvent. FIG. 14 shows an example of a microencapsulated thermochromic system.
There are a large number of ionochromic materials and material families from which to choose appropriate chemicals. Almost all of them can be used, depending on climate and color needs. The following is a list of representative ionochromic material families and a few example materials:
a) Phthalides
a. Phthaleins (see FIG. 16 )
i. Phenolphthalein ii. Crystal Violet Lactone (see FIG. 13 ) iii. Pyridyl Blue
b. Sulfophthaleins
b) Leucotriarylmethanes c) Azo Dyes (see FIG. 14 ) d) Styryl Dyes e) Chelates
a. Dimethylglyoxime b. 1,2-Dihydoxybenzenes c. 1-hydroxyanthraquinones
f) Crown Ethers g) Mono- and di-vinylphthalides
a. Diarylphthalides
i. general structure of a monovinylphthalide (see FIG. 21 ) ii. divinylphthalide which is green but strongly absorbs in near IR (see FIG. 22 ) iii. Fluorene
1. Green, IR-absorbing; versions of diarylphthalides with direct bonding between aryl rings (see FIG. 17 ) 2. green with absorbance tailing into IR when ring-opened (see FIG. 18 )
iv. Fluorans
1. Yellow, orange, pink/violet through to green oxygen bridged versions of diarylphthatides can be designed to give neutral colors, e.g. black. (see FIG. 19 ), e.g. fluoran which is almost a neutral black when ring-opened (see FIG. 20 )
h) Lactams
a. contains lactam (cyclic amide) ring used instead of lactone (cyclic ester).
i. general analogues of diarylphthalide (see FIG. 23 ) ii. xanthene-derived lactam, which is magenta when ring opened is (see FIG. 24 )
i) Sulfones
a. a sulphur analogue of the lactone-type.
i. General structure: (see FIG. 25 )
All three of the aforementioned materials can be generally referred to as thermomorphic materials. The microencapsulated thermomorphic material can be used to create a paint/coating that goes from one color to another (white to black, yellow to blue, dark purple to light pink, etc.) or from colored to colorless (blue to clear, black to clear, green to clear, etc.) which would then be painted over a reflective coating that would become visible at high temperatures when the thermomorphic material has gone colorless, thereby reflecting heat. The technology for microencapsulation is well known as are materials utilized in their manufacture.
Thermomorphic-microencapsulated materials can be used in coatings geared towards roof construction. These coatings can be used both in the factory and on the construction site. In the factory the materials can be sprayed on or used directly in the creation of roofing shingles, tiles, and mats. In this manner the roofing materials will gain the thermochromic properties of the coating with fewer impurities and less man-hours of work. On the construction site the thermomorphic coating can be applied, like a normal paint to existing roofing surfaces.
Many of the thermomorphic materials described above are sensitive to UV radiation and can loose their effectiveness upon sustained exposure to UV radiation. Thus, even though some of these materials need UV sensitivity to trigger the transition from absorbing to reflecting and vice-versa, some measure of UV protection is useful in extending the lifetime of these materials. Compounds that can absorb UV radiation are well known in the art. See, for example, the compounds disclosed in U.S. Pat. Nos. 5,705,146 and 6,084,118, and in the references cited therein.
2. Electrophoretic Panels
Electrophoresis is the migration of charged molecules, such as proteins or dye chemicals, within an electrical field. The separation of proteins in an electric field is based on the size, shape, and charge.
Electrophoresis originates as a laboratory method for obtaining information about proteins and other molecules. To obtain a uniform electric field with a constant magnitude and direction over a specified volume of space, two flat metal plates are set up parallel to each other as shown in the figure below. When the terminals of a power source with voltage V are connected to these plates, a uniform electric field E is produced between the plates, as indicated in the FIG. 26 .
Most electrophoretic methods use a supporting media, such as starch, paper, polycrylamide, or Agarose. The term “zone electrophoresis” refers to electrophoresis that is carried out in a supporting medium, whereas “moving-boundary electrophoresis” is carried out entirely in a liquid phase.
The roofing system of the present invention can be based on moving-boundary electrophoresis. As opposed to using proteins or other heterogeneous particles, homogenous particles that uniformly move at the same rate and distance under a given charge can be used. In so doing, light-colored, negatively charged particles can be encapsulated in a dark opaque medium. When combined with colorless/clear electrodes replacing the metal plates, a shift in color is achieved.
More specifically, when the particles are at the bottom of the medium, the dark medium occludes them, and results in the appearance of a uniform dark surface. When the charge is reversed, the particles collectively rise to the top, allowing them to reflect light before it is absorbed by the dark medium. This results in the appearance of a uniform light or white colored surface.
Alternatively, similar results can be achieved by using two groups of oppositely charged particles in a clear medium. If the negatively charged particles are dark in color and the positively charged particles are light in color, the positively charged particles will climb to the top and the negatively charged ones will fall to the bottom when a negative charge is applied to the top of the encapsulation. The result will be a light-colored surface. If the charge were reversed, the negatively charged particles will climb to the top, resulting in a uniformly dark surface, as shown in FIG. 27 .
Electrophoretic mats can be applied to roofing materials to produce panels. This can be done by directly bonding the electrophoretic material to backing paper through the use of an adhesive. These panels will only change color in response to a small electric charge or pulse. The pulse will be delivered via a single wire connected to each mat, and run underneath the mat to a central point. The panels will be connected to an electric thermostat, via the central wiring point, which will deliver a charge whenever the temperature exceeds a predetermined threshold. This will in turn alter the color from absorbent (dark) to reflective (white) or vice-versa. This threshold temperature can be set independently of the installation or manufacture of the panels. It is also worthy to note that the roof can be easily separated into zones that can change at different “trigger” temperatures; similarly, the roof's color can be changed manually at the owner's discretion.
3. Electrochromic Materials
When an electroactive species undergoes a change in color upon electron transfer or oxidation/reduction, the process is known as electrochromism. This process normally involves the passage of an electric current or potential and is reversible. During the process of coloration in electrochromic cells by passing a charge in one direction, a color can form in one or both of the electrodes or in the electrolyte adjacent to the electrodes. When the color is formed by reduction at a negative electrode it is called cathodic coloration and, conversely, at the anode it is anodic coloration.
The most common is the colored electrode type, in which the transparent electrodes are coated with an organic or inorganic polymer, which becomes colored on passing a charge through the cell. If both electrodes change color they must display complementary electrochromism: the color change that occurs by oxidation at the first electrode must be the same as that occurring by reduction at the second electrode. The degree of coloration can be controlled by the amount of charge passing through the cell. The cell is bi-stable; i.e. it remains colored, even in the absence of applied voltage, until an equal charge is passed in the opposite direction through the cell. In other words the coloration of the electrochromic cell is controllable and switchable on demand.
In the case of the colored electrolyte type, the two complementary electrochromes are dissolved in the electrolyte between the transparent electrodes. One becomes colored by oxidation and the other by reduction and consequently the electrolyte becomes colored. The electrolyte remains colored only while a current is being passed, becoming colorless once the charge is removed.
Electrochromes can be classified into three groups. In the first type the coloring species remain in solution; in the second type the reactants are in solution but the colored product is a solid; the third type are those where all the materials are solids. In solution electrochrome systems, as opposed to solution-solid or solid systems, the soluble electrochrome undergoes an electron transfer interaction on the surface of the appropriate electrode, involving either anodic oxidation or cathodic reduction, where it changes color and then returns back to the solution phase, i.e. a colored electrolyte is produced. A solution-solid electrochromes in its pale or colorless state is soluble in the electrolyte. However, on electron transfer, the colored form of the electrochrome that is produced is insoluble and is deposited onto the surface of an electrode. All inorganic electrochromes exist in the solid state in both the colorless and colored states, e.g. Prussian Blue and tungsten trioxide. Conducting polymers such as polyanilines, polypyrroles and polythiophenes also fall into this class of electrochromes.
Electrochromic materials pose a special opportunity. Their properties make them perfect as a possible replacement for the electrophoretic materials. Like the electrophoretic materials, these materials do not require a constant charge to maintain the color change. The same basic setup, that of clear plastic electrodes sandwiching the electrochromic materials, with the electrodes connected to a thermostat, could be used. Depending on cost this could be a better choice. As with electrophoretic panels, a thermostat threshold temperature can be set independently of the installation or manufacture of the electrochromic panels.
Although the thermomorphic materials described herein have been described in the context of roofing materials, it will be apparent to those skilled in the art that these same materials can also be adapted for use as wall coverings or building siding materials. The invention is defined by the appended claims.
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An energy-conserving building covering material includes a building panel, such as a roofing panel or siding panel, coated with a thermomorphic material that can change its energy reflectance. The thermomorphic coating material can be combined with a carrier material., or it can be encapsulated with a solvent and optionally a color former in a microcapsule suspended in the carrier material. Alternatively, the building panel can include an electrophoretic material sandwiched between two transparent panels acting as electrodes. The building panel, when covered with said coating material and carrier material combination, can reflect radiant energy during warmer temperatures and can absorb radiant energy during cooler temperatures and re-radiate said absorbed energy into an interior of a building.
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BACKGROUND
[0001] The subject matter disclosed herein relates to power generation systems. Specifically, the embodiments described herein relate to controlling a turbine system in low ambient temperatures.
[0002] In a power generation system, such as a gas turbine system, a compressor may be used to compress a fluid (e.g., air) prior to mixing the fluid with fuel for combustion. In low ambient temperatures, the power generation system may be configured to observe and maintain the operating limit of the compressor, particularly when the power generation system uses a low British Thermal Unit (BTU) fuel. Low BTU fuels include fuels that may have large concentrations of inert gases, synthetic gases, waste gases, and biomass gases.
[0003] To maintain the operating limits of the compressor in low ambient temperature conditions, the power generation system may be configured to intentionally under-fire. That is, the fuel flow is often reduced to account for reduced compression due to the design limits of the compressor in low ambient temperatures. Reducing the fuel flow may in turn lead to lower firing temperatures for the power generation system. However, intentionally under-firing the power generation system may also result in output loss, in terms of the power generated by the power generation system as well as a loss of exhaust energy which may be captured and used by other components, such as a heat steam recovery generator (HSRG). It would be beneficial to operate power generation systems in low ambient temperatures, particularly when utilizing low BTU fuels, such that the system maintains the compressor limits while minimizing intentional under-fire.
BRIEF DESCRIPTION
[0004] Certain embodiments commensurate in scope with the originally claimed invention are summarized below. These embodiments are not intended to limit the scope of the claimed invention, but rather these embodiments are intended only to provide a brief summary of possible forms of the invention. Indeed, the invention may encompass a variety of forms that may be similar to or different from the embodiments set forth below.
[0005] In a first embodiment, a system includes a fluid intake system configured to intake a fluid and a compressor system fluidly coupled to the fluid intake system and configured to compress the fluid. The system also includes a combustor system fluidly coupled to the compressor and configured to combust a fuel mixed with the fluid, as wells as a turbine system fluidly coupled to the combustor and configured to rotate a shaft mechanically coupled to a load. Further, the system includes an inlet bleed heat system fluidly coupled to the compressor and to the fluid intake system and configured to direct a compressor fluid from the compressor into the fluid intake system. The system also includes a controller operatively coupled to the inlet bleed heat system and configured to sense an exhaust temperature of the turbine system. The controller is configured to adjust the compressor fluid flow via the inlet bleed heat system based on the exhaust temperature.
[0006] In a second embodiment, a system includes a controller communicatively coupled to a compressor. The controller is configured to sense the exhaust temperature of a gas turbine system, wherein the gas turbine system is fluidly coupled to the compressor. The controller is also configured to derive a setpoint based on the sensed exhaust temperature. Further, the controller is configured to actuate an inlet bleed heat valve based on the derived setpoint and an ambient temperature. The inlet bleed heat valve directs a compressor fluid from the compressor into a fluid intake system which is fluidly coupled to the compressor upstream of the compressor and configured to intake a fluid.
[0007] In a third embodiment, a non-transitory, computer-readable medium includes executable code having instructions. The instructions are configured to receive an input corresponding to an exhaust temperature of a turbine system and retrieve a baseload control function for a compressor system coupled to the turbine system. The instructions are also configured to retrieve data corresponding to a design limit of the compressor system and determine the difference between the operating level of the compressor system and the design limit of the compressor system. Further, the instructions are configured to calculate an exhaust temperature bias based on the baseload control function and the exhaust temperature. The instructions are configured to actuate an inlet bleed heat valve based on the exhaust temperature bias and the difference between the operating level of the compressor system and the design limit of the compressor system. The inlet bleed heat valve directs a compressor fluid from the compressor system into a fluid intake system fluidly which is coupled to the compressor system upstream of the compressor system and configured to intake a fluid.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] These and other features, aspects, and advantages of the present invention will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein:
[0009] FIG. 1 is a schematic view of a power generation system, in accordance with an embodiment of the present approach;
[0010] FIG. 2 is a block diagram of a control system within the power generation system of FIG. 1 , in accordance with an embodiment of the present approach;
[0011] FIG. 3 is a cross-sectional view of a compressor within the power generation system of FIG. 1 , in accordance with an embodiment of the present approach;
[0012] FIG. 4 is a schematic view of a cold day system included in the power generation system of FIG. 1 , in accordance with an embodiment of the present approach; and
[0013] FIG. 5 is a flow chart illustrating a process for operating the cold day system of FIG. 4 , in accordance with an embodiment of the present approach.
DETAILED DESCRIPTION
[0014] One or more specific embodiments of the present invention will be described below. In an effort to provide a concise description of these embodiments, all features of an actual implementation may not be described in the specification. It should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation-specific decisions must be made to achieve the developers' specific goals, such as compliance with system-related and business-related constraints, which may vary from one implementation to another. Moreover, it should be appreciated that such a development effort might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure.
[0015] When introducing elements of various embodiments of the present invention, 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. When a set of guide vanes is described as “closed,” it is intended to mean that the blades of the guide vanes are positioned at a relatively small angle. When a set of guide vanes are described as “open,” it is intended to mean that the blades of the guide vanes are positioned at a relatively large angle.
[0016] Present embodiments relate to systems and methods for maintaining compressor operating limits and system output in power generation systems, such as gas turbine systems. Specifically, the techniques described herein use inlet bleed heat to maintain compressor operating limits in low ambient temperatures. More specifically, the techniques described herein relate to using inlet bleed heat to operate a compressor in low ambient temperatures, as well as adjusting the fuel schedule of the power generation system containing the compressor based on, for example, the inlet bleed heat adjustments. By utilizing inlet bleed heat to operate the compressor and adjusting the fuel schedule accordingly, the compressor may operate at the design limits during low ambient temperatures without a reduction in compression. As such, the power generation system may operate without intentionally under-firing (e.g., reducing the fuel flow) to account for reduced compression due to low ambient temperatures. As a result, the power generation system may remain at the desired firing temperature levels, increasing the output and exhaust energy of the power generation system in low ambient temperatures.
[0017] With the foregoing in mind, FIG. 1 illustrates a power generation system 10 that may be used to provide power to a load, such as an electric generator, a mechanical load, and so on. The power generation system 10 includes a fuel supply system 12 , which includes a fuel repository 14 and a fuel control valve 16 that controls the amount of fuel supplied to the power generation system 10 . The power generation system 10 further includes a fluid intake system 18 coupled to a fluid source 20 and a fluid control valve 22 that controls the amount of fluid supplied to the power generation system 10 . The power generation system 10 also includes a turbine system 24 which in turn includes a compressor 26 , a combustion system 28 containing one or more fuel nozzles 30 , a turbine 32 , and an exhaust section 34 . As shown in FIG. 1 , the exhaust section 34 may include a heat recovery steam generator (HRSG) 36 . Further, a control system 38 oversees certain aspects of the power generation system 10 . In particular, the control system 36 may work in conjunction with sensors 40 and actuators 42 to monitor and adjust the operation of the power generation system 10 . For instance, the sensors 40 may include temperature sensors, oxygen sensor, pressure sensors, speed sensors, fuel flow sensors, fuel type sensors, and the like, while the fuel control valve 16 and the fluid control valve 22 are examples of actuators 42 . The control system 38 may also include a cold day system 44 to monitor and adjust the performance of the power generation system 10 based on the design limits of the compressor 26 and which is described in further detail below.
[0018] During operation of the power generation system 10 , the fuel supply system 12 may provide fuel to the turbine system 24 via the fuel control valve 16 . Similarly, the fluid intake system 18 may provide oxidant fluid (e.g., air) to the compressor 26 via the fluid control valve 22 . The fluid is then compressed before being sent to the combustion system 28 . Within the combustion system 28 , the fuel nozzle(s) 30 inject fuel that mixes with the compressed fluid to create a fluid-fuel mixture that combusts before flowing into the turbine 32 . The combusted fluid-fuel mixture drives one or more stages of the turbine 32 , which may in turn drive a shaft connected to a load 46 . For example, the load 46 may be a generator to produce electricity. The combusted gases exit the turbine 32 and vent as exhaust gases through the exhaust section 34 . In the depicted embodiment, the exhaust gases pass through the HRSG 36 , which recovers the heat from the exhaust gases to produce steam. That is, the depicted power generation system 10 may be a combined cycle or co-generation system, such that the steam is used to drive a downstream steam turbine (i.e., a combined cycle system) or for a co-generation process. Additionally or alternatively, the exhaust gases may pass through other components within the exhaust section 34 , such as catalytic converter systems.
[0019] As mentioned above, the control system 38 may control certain aspects of the operation of the power generation system 10 . The control system 38 includes memory 48 , a processor 50 , and a hardware interface 52 for interacting with the sensors 40 and the actuators 42 , as depicted in FIG. 2 . As depicted, the processor 50 and/or other data processing circuitry may be operably coupled to memory 48 to retrieve and execute instructions for managing the power generation system 10 . For example, these instructions may be encoded in programs or software that are stored in memory 48 , which may be an example of a tangible, non-transitory computer-readable medium, and may be accessed and executed by the processor 50 to allow for the presently disclosed techniques to be performed. The memory 48 may be a mass storage device, a FLASH memory device, removable memory, or any other non-transitory computer-readable medium. Additionally and/or alternatively, the instructions may be stored in an additional suitable article of manufacture that includes at least one tangible, non-transitory computer-readable medium that at least collectively stores these instructions or routines in a manner similar to the memory 48 as described above. The control system 38 may also communicate with the sensors 40 and the actuators 42 via the hardware interface 52 , as stated above, including through wired and wireless conduits.
[0020] In some embodiments, the control system 38 may be a distributed control system (DCS), such that each component or a group of components may include or be associated with a controller for controlling the specific component(s). In these embodiments, each controller may contain memory, a processor, and a hardware interface similar to that of the control system 38 as described above. Further, in such embodiments, the controllers may include a communicative link to other controllers to coordinate decision-making.
[0021] Turning now to FIG. 3 , the compressor 26 may include several sets of blades 54 that are arranged in stages or rows around a rotor or shaft 56 . The compressor 20 is coupled to the fluid intake system 18 via an intake shaft 58 , and to the combustion system via an output shaft 60 . A set of inlet guide vanes 62 controls the amount of fluid (e.g., air) that enters the compressor 26 at any given time, in contrast to the fluid control valve 22 , which controls the amount of fluid delivered from the fluid intake system 18 to the compressor 26 . In particular, the angles of the blades of the inlet guide vanes 62 may determine the amount of fluid that enters the compressor 26 . When the angles of the blades are relatively small (i.e., “substantially closed”) less fluid is received, but when the angles of the blades are relatively large (i.e., “substantially open”) more fluid is received. The angles of the inlet guide vanes 62 may be controlled by the control system 38 , or, as described in further detail below, by the cold day system 44 .
[0022] During operation, the fluid travels through the compressor 26 and becomes compressed. That is, each set of blades 54 rotatively moves the fluid through the compressor 26 while reducing the volume of the fluid, thereby compressing the fluid. Compressing the fluid generates heat and pressure. In the present embodiments, the compressor 26 may be configured to re-circulate the compressor discharge (e.g., discharge fluid) back into the intake shaft 58 via an inlet manifold 64 . The re-circulated compressor discharge fluid is commonly referred to as “inlet bleed heat,” and may be used for a variety of functions, such as reducing icing on various inlets on the compressor 26 due to low ambient temperatures and protecting the compressor 26 when the inlet guide vanes 62 are closed. Accordingly, there are several commercially available inlet bleed heat systems that can be added to compressors such as the compressor 26 and incorporated into the operating software (e.g., control system 38 ) of the power generation system 10 . Advantageously, the techniques described herein apply the inlet bleed's temperature and pressure characteristics to more efficiently operate in certain environments, such as low ambient temperatures, for example, without a substantial reduction in compression.
[0023] As mentioned above, the control system 38 oversees the operation of the power generation system 10 , and ensures that each component operates within its design limits. To do so, the control system 38 may have different components and processes for monitoring each component, similar to the scheme for a distributed control system as described above. One such aspect of the control system 38 may be the cold day system 44 . The cold day system 44 may monitor the operation of the compressor 38 and, in some embodiments, the fuel system 12 , when the power generation system 10 operates during low ambient temperatures, and may control certain aspects of the system 10 based on the monitoring. In particular, the cold day system 44 may redirect a portion of the inlet bleed heat generated by the compressor 26 to be added to the intake fluid for the compressor 26 , and may control the fuel scheduling based on the amount of inlet bleed heat fed into the compressor 26 .
[0024] As will be described in further detail below, utilizing the inlet bleed heat as part of the intake fluid and adjusting the fuel scheduling may enable the compressor 26 to operate at desired margins (e.g., safety margins) of the design limits during low ambient temperatures. This, in turn, may reduce the amount of intentional under-firing of the power generation system 10 to account for compressor safety margins during low ambient temperatures, which subsequently improves the output of the power generation system 10 during low ambient temperatures. Particularly, the embodiments described herein may also improve the output of power generation systems 10 that utilize low BTU fuels during low ambient temperatures. Further, as noted above, because there are several commercially available inlet bleed heat systems, the embodiments described herein may be applied retroactively to power generation system 10 by utilizing a commercially available inlet bleed heat system and making modifications to the control system 38 as necessary. In some power plants having the system 10 , the modifications may be software only, while in other power plants, the modifications may include hardware and software modifications.
[0025] In present embodiments, the cold day system 44 is part of the control system 38 , and thus uses the sensors 40 , actuators 42 , memory 48 , and processor 50 , as described above. In other embodiments, the cold day system 44 may be configured on a controller as part of a distributed control system. In still other embodiments, the cold day system 44 may be separate from the control system 38 , and may communicate and work in conjunction with the control system 38 as necessary.
[0026] Turning now to FIG. 4 , the figure illustrates a schematic diagram of embodiments of the cold day system 44 communicatively coupled to the compressor 26 and combustor 28 . As stated above, the cold day system 44 oversees the operation of the compressor 26 , as well as other components of the system 10 . The cold day system 44 may utilize a baseload control curve 66 (or similar derivation) that represents normal operating procedures for the compressor 26 (i.e., no inlet bleed heat addition at low ambient temperatures). In present embodiments, the baseload control curve 66 corresponds to a compressor pressure ratio function, which compares the pressure of the fluid exiting the compressor 26 to that of the fluid entering the compressor 26 . Alternately or additionally, other baseload control curves 66 that quantify the operation of the compressor 26 may be used. The baseload control curve 66 may be stored or generated during operation by either the cold day system 44 or the control system 38 . In other embodiments, the baseload control curve 66 may be calculated offline and uploaded to the cold day system 44 or the control system 38 .
[0027] The cold day system 44 then determines an operating difference 68 between the design limits 70 of the compressor 26 and the current operating level 72 of the compressor 26 . The data representing the design limits 70 (e.g., pressures, flows, temperatures, speeds, compression ratios) may be stored on the memory 48 in embodiments in which the cold day system 44 is part of the control system 38 . Alternately, in embodiments in which the cold day system 44 is a controller within a distributed control system or separate from the control system 38 , the cold day system 44 may be configured to retrieve the design limits 70 from the control system 38 , or from memory in the cold day system 44 . In still further embodiments, either the cold day system 44 or the control system 38 may be configured to retrieve the design limits 70 from another component or system, such as a data repository containing information about the various components of the power generation system 10 . The current operating level 72 may be determined based on data received from the sensors 40 disposed in or around the compressor 26 , such as the temperature or pressure of the fluid exiting the compressor 26 . In some embodiments, the cold day system 44 may determine the operating difference 68 only when activated by a control signal. For instance, the cold day system 44 may only determine the operating difference 68 if the cold day system 44 or the control system 38 has determined that the ambient temperature is below a pre-set threshold.
[0028] Based on the operating difference, the cold day system 44 may control an inlet bleed heat valve 74 to add inlet bleed heat to the intake fluid of the compressor 20 . By adding the inlet bleed heat, which, as mentioned above, is included in a portion of the fluid generated by compressing fluid, the temperature of the intake fluid increases as a whole. This temperature increase, in turn, increases the amount of compression of the fluid, regardless of the operating level of the compressor 26 . That is, if the compressor 26 receives a fluid at a first temperature and then a second fluid at a second higher temperature, the compression at the lower temperature will be less than the compression the higher temperature, regardless of any change in the operation of the compressor 20 .
[0029] Adding inlet bleed heat enables the compressor 26 to more closely adhere to the desired compressor pressure ratio function, even when the compressor 26 operates at a reduced rate due to low ambient temperatures. Further, because the compressor 26 still may adhere to the desired compressor pressure ratio, the control system 38 does not need to reduce fuel flow in order to account for a decrease in compression. Accordingly, the power generation system 10 can then maintain the desired firing temperatures during low ambient temperatures. As such, the power generation system 10 may have increased output compared to other power generation systems in which firing temperature suppression is used to maintain compressor operating limits during low ambient temperatures. The power generation system 10 may also have increased exhaust energy, which may be used by downstream components, such as the HRSG 30 .
[0030] Once inlet bleed heat is added to the fluid intake, the temperature of the compressed fluid rises, as mentioned above. Subsequently, the compressor pressure ratio function, and other types of baseload control curves 66 , shift based on the inlet bleed heat addition. Additionally, the exhaust gas temperature of the turbine system 24 changes relative to the exhaust gas temperature of the turbine system 24 when no inlet bleed heat is added. Based on the shifted baseload control curves 66 , the cold day system 44 then calculates an exhaust temperature bias 76 that represents the change in the exhaust gas temperature due to the inlet bleed heat addition. The cold day system 44 then adjusts the inlet bleed heat addition or the fuel schedule for the turbine system 24 to maintain the desired firing temperature of the turbine system 24 while observing the design limits 70 of the compressor 26 .
[0031] Turning now to FIG. 5 , the figure depicts a flow chart of an embodiment of a process 80 suitable for adding inlet bleed heat during low ambient temperature conditions. The process 80 may be implemented as computer instructions stored in memory and executable by the cold day system 44 . The cold day system 44 may execute for the instructions to better maintain the design limits 70 of the compressor 26 during operation. Although the process 80 is described below in detail, the process 80 may include other steps not shown in FIG. 5 . Additionally, the steps illustrated may be performed concurrently or in a different order. The process 80 may be stored in the memory 40 and executed by the processor 42 , as described above.
[0032] Beginning at block 82 , the cold day system 44 may retrieve the baseload control curve 66 , which may correspond to the compressor pressure ratio function, or any other control function that quantifies the operation of the compressor 26 . As mentioned above, the cold day system 44 may retrieve the baseload control curve 66 from the memory 40 , the control system 38 , or an external system such as a data repository. Further, in other embodiments, the cold day system 44 may be configured to generate the baseload control curve 66 when the power generation system 10 is offline or during operation, or the curve 66 may be generated by the manufacturer and stored for use during system 10 operations.
[0033] At block 84 , the cold day system 44 compares the design limits 70 of the compressor 26 to the current operating level 72 of the compressor 26 to generate the operating difference 68 . Again, as mentioned above, the cold day system 44 may retrieve the design limits 70 from the memory 40 , the control system 38 , or an external system such as a data repository. The current operating level 72 (e.g., pressure, temperature, flow, speed, compression ratio) may be determined based on the data from the sensors 40 . In some embodiments, the current operating level 72 may be determined by the control system 38 , and the data passed to the cold day system 44 . Further, as mentioned above, the cold day system 44 may be configured to determine the operating difference 68 only upon receipt of an activation signal.
[0034] Next, at block 86 , the cold day system 44 determines whether to adjust the amount of inlet bleed heat addition to the fluid intake of the compressor 26 or adjust the fuel schedule of the turbine system 24 based on the baseload control curve 66 , the operating difference 68 , and the exhaust temperature bias 76 , if available. Further, in some embodiments, the cold day system 44 may also determine whether to adjust the inlet guide vanes 62 instead. If the cold day system 44 decides to adjust one of the three parameters, then it may proceed to block 88 , which is described in detail further below. If not, then the cold day system 44 returns to generating the operating difference 68 at block 84 .
[0035] At block 88 , the cold day system 44 adjusts the inlet bleed heat addition, the fuel schedule, and/or the inlet guide vanes 62 as determined in block 86 . To do so, the cold day system 44 actuates the inlet bleed heat valve 74 , the fuel control valve 16 , or the inlet guide vanes 62 . In some embodiments (e.g., in a distributed control system), the cold day system 44 may send a control signal to the control system 38 to actuate any of the inlet bleed heat valve 74 , the fuel control valve 16 , or the inlet guide vanes 62 .
[0036] Once the cold day system 44 adjusts the inlet bleed heat addition, the fuel schedule, or the inlet guide vanes 62 , the cold day system 44 then determines any changes to the control functions or parameters. That is, at block 90 , the cold day system 44 may determine any shifts in the baseload control curve 66 , the new operating level 72 of the compressor 26 and, subsequently, the operating difference 68 , or the exhaust temperature bias 76 . The cold day system 44 may then return to determining adjustments for the inlet bleed heat addition, the fuel schedule, or the inlet guide vanes at block 86 .
[0037] Technical effects of the invention include systems and methods for operating a power generation system during low ambient temperatures. Certain embodiments may enable components of the power generation system to operate at design limits during low ambient temperatures without reducing the output of the power generation system. For example, the present cold day system may add inlet bleed heat from the compressor to the fluid intake of the compressor, which may allow the compressor to operate at design limits during low ambient temperatures while producing the desired amount of compression. Accordingly, the present power generation system does not have to intentionally under-fire to account for reduced compression, which subsequently increases the output of the power generation system during low ambient temperatures. Further, in certain embodiments, the present cold day system may be applied retroactively to power generation systems by utilizing commercially available inlet bleed heat systems and modifications to the control system of the power generation system. The technical effects and technical problems in the specification are exemplary and not limiting. It should be noted that the embodiments described in the specification may have other technical effects and can solve other technical problems.
[0038] This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal language of the claims.
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A system includes a controller communicatively coupled to a compressor. The controller is configured to sense an exhaust temperature of a gas turbine system fluidly coupled to the compressor and derive a setpoint based on the sensed exhaust temperature. The controller is also configured to actuate an inlet bleed heat valve based on the derived setpoint and an ambient temperature. The inlet bleed heat valve directs a compressor fluid from the compressor into a fluid intake system fluidly coupled to the compressor upstream of the compressor and configured to intake a fluid.
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BACKGROUND OF THE INVENTION
Table saws are valuable tools used for a variety of tasks, such as cross-cutting wood and plastic, and ripping long boards into narrow strips. While there are a variety of table saw designs, most table saws include a circular saw blade mounted on an arbor that is turned by one or more belts that are driven by a motor. The saw blade extends through an opening in the surface of a saw table, on which surface the workpiece rests and is supported. The depth of cut is varied by adjusting the amount of the blade that extends above the table surface such that the higher the blade extends above the table, the deeper the cut that is made in the material. Angle of the cut with respect to the table surface is typically controlled by adjusting the angle of the arbor to which the blade is affixed.
Additionally, table saws nearly always include a fence or guide that extends from a side of the table nearest the operator to a side furthest from the operator, and is oriented to be generally parallel to a cutting plane of the blade. The rip fence is used to guide the workpiece during the process of making a “rip cut,” which is a cut made parallel to a grain of the wood, and guides the workpiece as the workpiece is fed onto the saw blade. A distance of the fence from the blade may be adjusted, thereby determining a location of the cutting surface on the workpiece. Accurate and precise positioning of the workpiece is important to accurate and precision cutting tasks.
However, while conventional rip fences provide some adjustability with respect to a distance at which it is disposed from a cutting plane of the saw blade, the parallelism of the rip fence with the cutting plane of the saw blade can sometimes be compromised depending upon the particular design of the rip fence mechanism. Unfortunately, lack of parallelism or “trueness” not only accounts for inaccurate and imprecise cutting, it may result in a flawed workpiece that exhibits “burning” as the saw blade cuts at an unintended angle. Moreover, lack of parallelism may also result in a dangerous condition wherein the workpiece is kicked back toward the tool operator.
Accordingly, precision alignment of the fence and its parallelism with the cutting plane of the saw blade are of critical importance in making precise and accurate cuts in the workpiece.
SUMMARY OF THE INVENTION
The instant invention includes various embodiments of a device and method for promoting parallelism, or “trueness,” between a plane of a rotary cutting blade that is at a right angle to a surface of a table and a rip fence of a table saw assembly. Specifically, embodiments of the invention include a rip fence that may be zeroed at a predetermined location, such as when near or in abutment with the rotary cutting blade, and then moved away from the rotary cutting blade for a predetermined distance such that the distance from a cuffing surface of the rotary cutting blade as well as its orientation with respect to the rotary cutting blade may be determined. Preferably, a front and a rear end of the rip fence include a mechanism whereby the respective distances from the rotary cutting blade may be determined, and that even minute differences in the respective distances may be reconciled to promote trueness between the rip fence and the cutting surface of the rotary cutting blade.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front perspective view of a table saw, rip fence, and front and rear sensor assemblies according to a preferred embodiment of the invention;
FIG. 2 is a front perspective view of a table saw and rip fence according to another embodiment of the invention;
FIG. 3 is a side perspective view of a front sensor assembly illustrated in FIG. 2 ;
FIG. 4 is a rear perspective view of a table saw, rip fence and rear sensor assembly according to the embodiment illustrated in FIG. 2 ;
FIG. 5 is a side perspective view of the table saw, rip fence and rear sensor assembly illustrated in FIG. 2 ;
FIG. 6 is a front perspective view of the rear sensor assembly according to FIG. 2 ;
FIG. 7 is a front perspective view of a table saw, rip fence, and front and rear sensor assemblies according to an alternate embodiment of the invention;
FIG. 8 is a front perspective view of a table saw and rip fence according to another embodiment of the invention;
FIG. 9 is a side perspective view of the front sensor assembly of the embodiment illustrated in FIG. 8 ; and
FIG. 10 is a side sectional view of the table saw and rip fence illustrated in FIG. 8 .
DETAILED DESCRIPTION OF THE INVENTION
While it is contemplated that the invention may be used with a variety of conventional table saw assemblies, such as those manufactured under the SKIL and BOSCH brands by the S-B Power Tool Corporation of Chicago, Ill., one exemplary table saw assembly, indicated generally at 10 , is illustrated in FIG. 1 in connection with a first embodiment of the invention. According to the embodiment illustrated in FIG. 1 , a rotary cutting blade 12 extends upwardly through a blade bracket 14 , which is an elongated slot disposed in a generally middle portion of a table 16 . A pair of miter gauge slots 18 (best shown in FIG. 2 ) are also preferably provided, one on each side of the blade bracket 14 , and extending from a front end 20 of the table 16 to a rear end 22 of the table. While the rotary cutting blade 12 may be tiltable for miter cutting, a radial plane 24 of the rotary cutting blade 12 generally extends perpendicularly with respect to a plane of the table.
An elongated, generally rectangular rip fence, indicated generally at 26 , is also provided with the exemplary table saw assembly 10 , wherein the rip fence has a length corresponding generally to a length of the table 16 , which is defined as a depth of the table as measured from the front end 20 to the rear end 22 of the table. The rip fence 26 is configured to be slidable with respect to a top surface of the table 16 . Thus, the rip fence 26 has a front end 28 that engages the front end 20 of the table 16 and a rear end 30 that engages a rear end 22 of the table and has an elongated rectangular body 32 . The rip fence 26 can move along a width of the table between the rotary cutting blade 12 and a predetermined location on the table, where the width of the table is defined as extending between side ends 33 . A guide plane 34 of the rip fence 26 is configured and arranged to face the blade bracket 14 .
This embodiment contemplates that the table 16 and the rip fence 26 include complementary measurement mechanisms whereby a distance from the radial plane 24 of the rotary cutting blade 12 to a predetermined location on the table may be accurately and precisely measured, and whereby parallelism between the radial plane and the rip fence 26 may be accurately and precisely ascertained to promote accurate and precise cutting. Specifically, it is contemplated that the rip fence 26 may include one or more of a plurality of positional sensing mechanisms for sensing and/or displaying a location of the rip fence 26 relative to a predetermined reference point, such as the rotary cutting blade 12 . The sensing mechanisms may include, but should not be construed as being limited to, electronic sensors, digital readouts, pointers, or measurement indicia such as scoring or other markings disposed on the rip fence 26 , preferably at the front and rear ends 28 , 30 . Similarly, it is contemplated that the table 16 includes corresponding positional sensing indicators for detecting a position of the rip fence 26 , such as electronic indicators, digital readouts, pointers or measurement indicia to reference or communicate with the rip fence to give visual or other indication to an operator as to the position of the rip fence relative to the blade.
For example, turning again to FIG. 1 , the rip fence 26 according to the preferred embodiment includes a front sensor assembly, indicated generally at 36 , and a rear sensor assembly, indicated generally at 38 , each of which preferably includes a positional sensor 40 . At least one LCD screen 44 is preferably provided to indicate a variety of parameters, such as displacement of the rip fence 26 from the rotary cutting blade 12 and the parallelism of the rip fence to the rotary cutting blade. The positional sensors 40 may be one of a plurality of mechanisms, such as an optical reflective reader, a capacitor, a magnet, or a pointing device, to name a few.
FIG. 1 illustrates the front and rear positional sensors 40 to be optical reflective readers. The table 16 correspondingly includes positional indicators, such as a plurality of sensor reference points 46 , which may be sensed by the respective positional sensors 40 . Sensor reference points 46 may include one of a plurality of mechanisms, such as a strip of electrical contacts to be read by the positional sensors 40 , magnets, a series of bar codes disposed at predetermined increments (e.g., 1/64″), or contrasting stripes to be read by an optical reflective reader, to name a few.
As illustrated in FIG. 1 , the sensor reference points 46 include a strip having a plurality of contrasting stripes, wherein the stripes have a predetermined width, preferably 1/16″. A predetermined number of sensors disposed within each of the contrasting stripes, preferably four, electronically divide the contrasting stripes, thereby rendering an enhanced resolution. For example, where four sensors are included in each of the contrasting stripes gives a resolution of 1/64″.
In contrast, FIG. 2 illustrates another embodiment according to the invention whereby the positional sensors include positional transducer sensing head 47 a and interacting strip 47 b , which may be optical, mechanical magnetic or capacitive, to name a few. Alternatively, a string driven positional transducer (not shown) may also be used. For example, a capacitive-based interacting strip would have a series of copper pads at equal intervals such as ⅛″ shown as item 46 on item 47 b.
The table 16 also preferably includes structural features that promote sliding of the rip fence 26 along the surface of the table 16 . These features are commonly known in the art, and include rails on which the fence can slide. Depending on the particular embodiment, additional structural features may be provided to promote sliding of the positional sensors 40 with the rip fence 26 .
For example, turning again to the embodiment illustrated in FIGS. 2-5 , the table 16 may also include front and rear sliding brackets 48 , 50 , one at each of the respective front and rear ends 20 , 22 along the width of the table as measured from between the sides 33 of the table, for purposes of convention. Depending on the particular sensor assembly used with the table, the sliding brackets 48 , 50 may assume a variety of configurations. The front and rear sensor assemblies 36 , 38 are operatively coupled to the rip fence 26 , and reciprocate along the respective front and rear sliding brackets 48 , 50 when the rip fence is moved.
Turning to the front sliding bracket 48 of the embodiment illustrated in FIGS. 2 and 3 , the front sliding bracket is generally rectangular in shape, having a length extending between sides 33 of the table 16 , with an outside surface 56 including a longitudinal slot 58 therein. A lower portion 60 of the front sliding bracket 48 depends downwardly from a top surface of the table 16 , and the front sensor assembly 36 is coupled to the lower portion of the front sliding bracket 48 such that the front sensor assembly is lower than the top surface of the table 16 , while the rip fence 26 is coupled to an upper portion of the front sliding bracket, thereby operatively coupling the rip fence and the front sensor assembly. Thus, the front sensor assembly 36 moves along the longitudinal slot 58 as the rip fence 26 moves along a surface of the table 16 .
A front mounting bracket, designated generally at 61 , is preferably provided to couple the rip fence 26 to the front sliding bracket 48 . The front mounting bracket 61 includes a generally horizontal portion 61 a and a generally vertical portion 61 b disposed at right angles to one another to receive the generally rectangular sliding bracket 48 therein. The front mounting bracket 61 is thereby operably coupled to both the rip fence 26 and the sliding bracket 48 , and may slidably engage the sliding bracket to promote movement of the rip fence along the width of the table 16 .
Similarly, the rear sensor assembly 38 , which is best illustrated in FIGS. 4 and 5 , is also operatively coupled to the rip fence 26 such that as the rip fence moves, the rear sensor assembly moves. Specifically, the rear sliding bracket 50 (best shown in FIGS. 4 and 5 ) includes a sliding rail 62 that is coupled to an extreme rear end 22 of the table 16 and is vertically displaced from the top surface of the table to be elevationally lower than the top surface of the table. A mounting bracket 64 is mounted to the sliding rail 62 and configured to be slidingly engaged thereto.
The mounting bracket 64 is preferably generally rectangular in shape, with a longitudinal groove 66 extending along a top portion thereof. The rip fence 26 is mounted to the mounting bracket 64 , preferably via a mounting extension 68 having a downwardly depending fastening element 70 , such as a pin, configured to lockingly engage the longitudinal groove 66 . Similarly, the rear sensor assembly 38 is coupled to the mounting extension 68 on a mounting side 72 thereof, and a lower rear end portion 74 is lockingly engaged to the mounting bracket 64 .
Thus, the rear sensor assembly 38 is operably coupled to both the rip fence 26 and the mounting bracket 64 such that the rear sensor assembly moves with the rip fence as it moves. The positional sensor 40 is disposed at a right hand side of the rear sensor assembly 38 as viewed in FIG. 4 .
In the preferred embodiment illustrated in FIG. 1 , a single LCD screen 44 is configured and arranged on a top surface of the rip fence 26 , whereas in alternative embodiments, LCD screens 44 may be disposed at each of the front and rear sensor assemblies 36 , 38 . As illustrated in FIGS. 2 and 3 , where LCD screens are provided on each of the front and rear sensor assemblies 36 , 38 , the LCD screens preferably face the front end of the table for easy reading by the operator.
Thus, in operation of any of the embodiments, the rip fence 26 is brought into abutment with the radial plane 24 or other predetermined position, at which point the sensors are zeroed by activating a zeroing mechanism 76 disposed on the rip fence. The operator may then move the rip fence 26 to a predetermined location at a desired distance from the rotary cutting blade 12 , and may determine the distance from the blade by reading the one or more LCD screens 44 disposed within the front and rear sensor assemblies 36 , 38 , or within the rip fence 26 itself. The distance of the rip fence 26 from the rotary cutting blade 12 is an average of the respective distances of each of the positional sensors 40 , which may be expressed as follows: (x 1 +x 2 )/2, where x 1 is a displacement of a first positional sensor and x 2 is a displacement of a second positional sensor.
Parallelism, on the other hand, may be determined by the absolute value of the difference between x 1 and x 2 as follows: |x 1 −x 2 |. Once the operator knows the parallelism, the operator may readjust the fence to resolve any discrepancy such that the absolute value of the difference between x 1 and x 2 approaches zero, indicating parallelism of the rip fence 26 with the rotary cutting blade 12 . A locking mechanism, such as a clamping lever 79 disposed at the front end 28 of the rip fence 26 , may then be pivoted into a locking position to lock the rip fence into position.
FIG. 7 illustrates yet another embodiment of the invention that includes a rip fence 26 wherein the positional sensors 40 consist of physical indicators, such as pointers 80 disposed at each end of a mounting bracket 82 coupled to the rip fence. Correspondingly, top surfaces of the sliding brackets 48 , 50 include measurement indicia 84 at predetermined increments. The measurement indicia 84 on each of the respective sliding brackets 48 , 50 are calibrated with one another such that corresponding measurements oppose one another across the table from a front end 20 to a rear end 22 . Thus, as the rip fence 26 is moved away from the rotary cutting blade 12 , the pointers 80 will point to a specific measurement such that the operator can readjust and reposition the rip fence until each respective pointer is pointing at the same measurement, indicating a common distance from the radial plane 24 by front and rear ends 28 , 30 of the rip fence, thereby indicating parallelism.
Turning now to FIGS. 9-10 , to promote a greater range of motion for the rip fence 26 , some table saws also include a side extension 86 that is configured to be extendable in a direction of the right side 54 of the table 16 . More specifically, the side extension 86 is typically a slideable panel that is coupled to the table 16 via one or more rails 87 . While it is possible to have the side extension 86 slide relative to the rails (not shown) via a coupling mechanism disposed on an underside of the slide extension, it is also plausible that the rails themselves slideably and telescopically extend from the table 16 to thereby move the side extension. Irrespective of the manner in which it extends, the side extension 86 provides for a predetermined length of extra movement of the rip fence 26 .
For example, typically the distance from the radial plane 24 and the guide plane 34 of the rip fence 26 reaches a maximum at a predetermined location toward the right end 54 of the table 16 , such as between approximately 13 and 18 inches, with restriction placed on further movement by a hard stop (not shown) disposed at the right end 33 of the table, which abuts a right end of the sliding brackets 48 , 50 , as well as by a partial length of the sliding brackets themselves, wherein a right side of each abuts the hard stop. Accordingly, the side extension 86 provides for a predetermined increment of extra movement, such as between approximately 11 and 20 inches.
In operation, the operator would slide the rip fence 26 to an extreme rightward position, at which point the operator would extend the slide extension 86 away from the table 16 to provide for an additional length of movement. However, because the rip fence 26 is no longer moving relative to the table 16 as the slide extension 86 is moved, additional provision is optionally contemplated by the invention to promote continued measurement of both the displacement and parallelism of the rip fence.
Any one of a plurality of mechanisms is contemplated by the invention to address parallelism and distance in table saw assemblies 10 that include the slide extension 86 . For example, spooled measuring devices 88 , such as tape measures, may be provided, with a spindle thereof coupled to the table 16 at a the front and rear ends 20 , 22 , and a leading end of a tape coupled to the side extension 86 at front and rear ends such that as the side extension is moved, the tape would uncoil to indicate the additional displacement on either side. A disparity in the displacement would indicate a lack of parallelism, which may then be corrected by the operator.
As illustrated in FIG. 9 for example, the spooled measuring device 88 is preferably coupled to the table 16 such that it spools out the measuring tape as the sliding rail 87 moves relative to the table. More particularly, the spooled measuring device 88 is preferably coupled to the table 16 via fasteners, preferably bolts 92 , where the bolts extend through a length of the mounting block and into the table 16 to secure the mounting block and spooled measuring device to the table. A slot 94 is provided in the sliding rail 87 such that sliding rail may move relative to the stationary mounting block 90 for a predetermined distance, as a corresponding amount of measuring tape is spooled out from the spooled measuring device 88 .
While various embodiments of the present invention have been shown and described, it should be understood that other modifications, substitutions and alternatives are apparent to one of ordinary skill in the art. Such modifications, substitutions and alternatives can be made without departing from the spirit and scope of the invention, which should be determined from the appended claims.
Various features of the invention are set forth in the following claims.
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A power table saw of the type which has a generally rectangular table with front and rear end portions, a motor operatively coupled to drive a rotary cutting blade extending upwardly through a top of the table, the table saw including an elongated fence having front and rear end portions, and being configured to be laterally movable along the width of the table and be secured to the front and rear end portions of the table, front and rear releasable locking mechanisms operatively associated with the front and rear end portions of the fence for locking each end portion to the end portions of the table, and at least one positional sensor provided with each of the front and rear end portions of the fence for determining the lateral position of each end portion of the fence along the width of the table.
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FIELD OF THE INVENTION
The invention relates to steam irons, and more in particular to the control of steaming functions of such irons.
BACKGROUND
A domestic steam iron has the capability to generate steam and to subsequently release this steam through outlet openings provided in the soleplate of the iron. The steam, which is applied directly to a garment being ironed, helps to diminish the ironing effort and to improve the ironing result.
Modern steam irons may come equipped with a steam rate control, for example in the form of a turnable knob or a slider provided on the iron housing. While a low steam rate setting may suffice for efficiently ironing moderately creased clothes (or patches thereof), a high steam rate setting may be selected to aid in the removal of tough wrinkles. The control allows the user at any time to select the steam rate setting that is appropriate for the (patch of) garment at hand. Practice shows, however, that some if not most users do not bother to adjust the steam rate once they have started an ironing session. Accordingly, when the maximum steam rate has been selected initially, the iron may remain set to produce larger amounts of steam than necessary for achieving a proper ironing result. Moreover, many users tend to park an iron horizontally between different ironing strokes, e.g. during garment changing or rearrangement, which results in continuation of maximum steam production during idle time.
In an attempt to put a curb on the energy wastage that is associated with such use of a steam iron, it has been suggested to fit the iron with an intuitively operated handle that controls the steam rate. See for an example of such an iron FR602293. The working of an intuitive handle may rely on the downward force that is exerted by a user's hand as he steers the iron across a garment. In general, a user will intuitively apply a larger downward force on the handle as the degree of wrinkling in a garment increases. The applied force may thus be taken as a measure of the desired steam rate. When no force is applied, for example when the iron is parked on an iron rest, the production and/or release of steam may be halted.
Although the intuitive handle seems to provide a solution to the problem of energy wastage due to unnecessary steam production, research has shown that the range of forces exerted on a handle by an ironing user varies per individual. This means, inter alia, that the minimum force that is applied during an ironing session is individual-dependent. In addition, individual users do not display consistent force-exertion behaviour across different ironing sessions either. As an intuitive handle has a minimum force threshold that must be exceeded in order to activate it, users of an iron with such a handle may not, or not at all times, automatically apply sufficient force on the handle to bring about the release of steam. Furthermore, even though the handle may thus work unsatisfactorily, it may not be possible to put the handle out of action or to override it, and to specify the desired steam rate in a different manner.
SUMMARY
It is an object of the present invention to provide for a steam iron that overcomes or mitigates one or more of the above-described problems.
To this end, a steam iron is provided that includes a handle, moveable between a first handle position and a second handle position, whereby a biasing mechanism is provided to bias the handle into the first handle position. The steam iron also includes a user-control, adjustable between a first state and a second state, and a steam rate control assembly, operatively connected to the handle and the user-control, and configured to set a steam rate of the steam iron. The steam rate control assembly is configured such that the steam rate is set based on the user-control, irrespective of the position of the handle, when the user-control is in the first state; and such that the steam rate is set based on at least a position of the handle when the user-control is in the second state.
A steam iron according to the present invention provides a bipartite steam rate control, based on the synergetic combination of the two controls discussed above: a user-control, which allows a user to consciously set a desired steam rate, and an intuitively operated handle, which may conditionally provide the steam rate control assembly with corrective, energy saving input. Advantageously, the user-control enables the user to put the intuitive handle out of action in case it does not function satisfactorily, e.g. when ironing only mildly creased clothes, or in case its operation is not required, e.g. when no steaming is desired at all. Depending on the desired functionality, the first state of the user-control may comprise two or more selectable user-control positions, each of which may be associated with its own steam rate. The more first-state user-control positions, the wider the choice available to the user to unambiguously select the desired steam rate, independent of the handle position.
In an advantageous embodiment, the steam rate control assembly is configured such that a steam rate that is set when the user-control is in its first state is smaller than a steam rate that is set when the user-control is in its second state.
That is to say, the first state of the user-control corresponds to one or more relatively low steam rates, while the second state of the user-control corresponds to one or more medium or high steam rates. Since the user-control is operated consciously, a user may determine whether he desires a low or a high steam rate. When a low steam rate is selected, the iron's energy consumption is moderate, and there is little need for corrective, energy saving input from the intuitive handle. Besides, the selection of a low steam rate indicates that only mildly creased garments are being ironed, such that the force that is intuitively exerted on the handle might easily be too small to activate it anyway. When the need for energy saving action arises, however, i.e. when a medium or high steam rate is selected, the steam rate control assembly will automatically involve input from the intuitive handle in setting the steam rate. As the conscious selection of a high steam rate indicates that more heavily wrinkled garments are being ironed, the force exerted on the intuitive handle will typically suffice to activate it.
The arrangement may be such that the user-control is primarily concerned with the selection a desired base steam rate. When the steam rate set by the user-control exceeds a certain threshold, whereby the user-control passes into its second state, the base steam rate may be fixed at the threshold value and the intuitive handle may be put in action to provide an extra dosage of steam in dependence of the force exerted thereon. Release of the handle will then ensure a return to the base steam rate to save energy.
These and other features and advantages of the invention will be more fully understood from the following detailed description of certain embodiments of the invention, taken together with the accompanying drawings, which are meant to illustrate and not to limit the invention.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 is a schematic side view of an exemplary steam iron according to the present invention;
FIG. 2 is a schematic side view of a steam rate control assembly as shown in FIG. 1 ;
FIGS. 3 and 4 illustrate the operation of the exemplary mechanical steam rate control assembly shown in FIG. 2 when the user-control is in its first state; and
FIGS. 5 and 6 illustrate the operation of the exemplary mechanical steam rate control assembly shown in FIG. 2 when the user-control is in its second state.
DETAILED DESCRIPTION
FIG. 1 schematically shows an exemplary embodiment of a steam iron 1 according to the present invention. It will be appreciated that several components of the iron which are well known and have no particular relevance to the present invention are omitted for reasons of clarity.
Steam iron 1 comprises a housing 2 that is fitted with an intuitively operated handle 4 . Handle 4 is pivotable between a first, elevated position and a second, lower position around a hinge 6 that connects the handle 4 to the housing 2 . In FIG. 1 , the handle 4 is hinged near its front end, though in other embodiments it may be hinged at other points, such as its middle or its back end. Due to the action of a biasing mechanism 8 , handle 4 resides in its first position when no external, downward force is applied thereto. The biasing mechanism may, for example, be integrated in hinge 6 in the form of a spring hinge, as shown in FIG. 1 . Alternatively, it may be provided in a fulcrum 38 of a lever 34 (to be discussed hereafter) that is connected to the handle. Handle 4 is operably connected to a steam rate control assembly 30 . The steam rate control assembly 30 includes a valve 32 , that is disposed in a water channel 10 that leads from a refillable water reservoir 12 to outlet openings 14 in the heated soleplate 16 . When valve 32 is in an open position, water is allowed to flow from reservoir 12 , through valve 32 , to a heated steam chamber 18 . In steam chamber 18 , the water is converted from its liquid form into steam, after which it is released through outlet openings 14 in soleplate 16 . Naturally, when the valve 32 is in a closed position, no water flows from the water reservoir to steam chamber 18 , and no steam is produced or released.
Although FIG. 1 depicts a steam iron 1 with an integrated water reservoir 12 , i.e. a water reservoir integrated into the housing 2 that is purposefully moveable by the user during ironing, it is noted that in another embodiment of the steam iron the water reservoir may be arranged external to said housing 2 in a stationary body. This arrangement is common in so called system iron, which, as a rule, feature a relatively large water reservoir and a pressurized steam chamber upstream of the handle-operated valve 32 . In contrast to the embodiment of FIG. 1 , in which the valve 32 controls a flow of liquid water, the valve in these steam iron systems may control a flow of steam. This is a result of the fact that heating of the water in the former embodiment tends to be taken care of downstream of the valve 32 , in steam chamber 18 near the soleplate 16 of the iron 1 , while in the latter embodiment heating is provided for in the aforementioned external, pressurized steam chamber.
Attention is now invited to the construction and operation of the steam rate control assembly 30 . The construction of the steam rate control assembly 30 will be described first with reference to FIG. 2 . Subsequently its operation will be clarified with reference to FIGS. 3-6 .
Referring primarily to FIG. 2 , the exemplary steam rate control assembly 30 comprises a support structure 31 to which a steam shaft 58 , a switch 42 and a lever 34 are moveably connected. A lower end of the steam shaft 58 coincides with the aforementioned valve 32 . Said lower end normally extends through a valve opening 33 (see FIG. 1 ) and tapers off to a point. When the steam shaft 58 is in its lowest position, its lower end may block the valve opening 33 completely. However, when the steam shaft 58 is raised, the valve opening 33 is gradually freed as the tapered end 32 retreats therefrom. This allows for an increasing flow of water from the water reservoir 12 to the steam chamber 18 . The higher end of the steam shaft 58 is formed by a steam shaft bracket 56 , which is slideably moveable in a generally vertical direction within the support structure 31 . The steam shaft bracket 56 is spring-loaded by a spring 60 that forces the steam shaft bracket 56 , and hence the steam shaft 58 as a whole, upwards. The highest position that may be occupied by the steam shaft bracket 56 at any time is restricted by one of the switch 42 and the lever 34 .
The switch 42 comprises a selector pin 44 , a guide slit 46 and a spring-loaded switch body 48 . The selector pin 44 may be operatively connected to a user-control that is accessible from the outside of the housing 2 of the steam iron 1 . Said user-control may take any suitable form, and for example be a turnable knob, a dial, a slider, etc. Alternatively, when the selector pin 44 is itself suitably shaped and positioned, the selector pin 44 may be identified with a user-control. The selector pin 44 is slideably moveable within the guide slit 46 that is provided in the support structure 31 . The guide slit 46 extends slantingly upwards, as can be best seen in FIG. 3 . The switch body 48 is also slideably moveable within the support structure 31 , in a generally vertical direction. It deserves notice that this direction has a component that is perpendicular to the direction in which the guide slit 46 extends. The switch body 48 is spring-loaded by a spring 54 and serves, inter alia, to define a number of selectable selector pin positions, each of which is associated with its own steam rate. To this end, a top surface of the switch body 48 is provided with serrations 50 between any two of which the selector pin 44 is partly receivable. The spring action of spring 54 forces the switch body 48 upwards to lock the selector pin 44 in place between a selected pair of serrations 50 and an upper edge of the guide slit 46 . The selected position of the selector pin 44 determines the vertical position of the switch body 48 . Depending on its vertical position, an arm 49 of the switch body 48 may contact a top end of the spring-loaded steam shaft bracket 56 to restrict the upward movement thereof. Typically, such restricting contact occurs only when the selector pin 44 occupies one of the more left selector pin positions, which correspond to a relatively low vertical position of the switch body 48 . When the upward movement of the spring-loaded steam shaft bracket 56 is not restricted by the arm 49 of the switch body 48 , it may be restricted by contact with the lever 34 instead.
The lever 34 comprises a lever effect end 36 , a lever load end 40 and a lever fulcrum 38 . The lever effect end 36 is operably connected to the intuitive handle 4 , either directly or through the intermediation of an optional link mechanism. The connection is such that a downward movement of the handle 4 towards its second, lower position corresponds to a clockwise rotation of the lever 34 around the fulcrum 38 . It is understood that the clockwise rotation of the lever 34 involves the lifting of the lever load end 40 . When no downward force is exerted on the handle 4 , the biasing mechanism 8 will force the handle 4 into its first, elevated position such that the lever 34 is rotated in a counter-clockwise direction and the lever load end 40 is lowered. The counter-clockwise rotation of the lever 34 may be halted when the handle 4 reaches its first position or when the lever effect end 36 contacts a stop 62 provided by the support structure 31 . The lever load end 40 may interact with the steam shaft bracket 56 at the stop 57 provided thereon. Contact with the stop 57 , however, will not halt a counter-clockwise rotation of the lever as the biasing mechanism 8 is configured to overcome the spring action of spring 60 .
With regard to the terminology, it is noted that the positions of the selector pin 44 that effect a situation wherein the upward motion of the steam shaft bracket 56 is restricted by the switch body 48 , and not by the lever load end 36 in its lowest position, may define the first state of the user-control. Any position of the selector pin 44 that effects a situation wherein the lever load end 36 in its lowest position restricts the upward motion of the steam shaft bracket 56 , on the other hand, corresponds to a user-control in its second state.
FIGS. 3-6 illustrate the operation of the steam rate control assembly 30 shown in FIG. 2 . FIGS. 3 and 5 show the steam rate control assembly 30 with the lever 34 in its rest position, while FIGS. 4 and 6 show the assembly 30 with the lever 34 in a rotated position that corresponds to a pressed-down intuitive handle 4 .
In FIGS. 3 and 4 , the steam rate control assembly 30 is shown at a low steam rate setting. The selector pin 44 occupies a position between the two leftmost serrations 50 of the switch body 48 , which position corresponds to a user-control in its first state. As can be seen, the lever load end 40 does not contact the stop 57 , and the upward movement of the steam shaft bracket 56 is restricted by the contact between its upper end and the arm 49 of the switch body 48 . As shown in FIG. 4 , a clockwise rotation of the lever 34 merely increases the gap between the lever load end 40 and the stop 57 . The rotation does not influence the position of the steam shaft 58 . Accordingly, the steam rate of the iron is determined only by the position of the selector pin 44 . In an embodiment of the steam iron, the handle 4 may be locked in place when the user-control is in the first state. This would prevent the handle 4 from pivoting idly, i.e. without controlling the position of the steam shaft 58 , which might lead a user to think that the user-control is actually in the second state and not functioning. The locking of the handle may be effected in numerous ways, as will be apparent to one skilled in the art.
Departing from the situation shown in FIGS. 3 and 4 , the steam rate of the iron may be increased by sliding the selector pin 44 in an oblique, upward right direction through the guide slit 46 . The selector pin 44 will consecutively lock in place between different serrations 50 of the switch body 48 , which at the same time causes the spring-loaded switch body 48 to be moved upward. The upward motion of the switch body 48 , and in particular its arm 49 , allows the spring-loaded steam shaft 58 to rise as well. Since elevation of the steam shaft 58 lifts the tapered end 32 thereof from the valve opening 33 , an upward right movement of the selector pin 44 leads to an increased valve opening, and hence an increased steam rate of the iron 1 .
At some point, the sliding selector pin 44 will effect a situation wherein the steam shaft bracket 56 touches the lever load end 40 at stop 57 , and loses contact with the arm 49 at its top end. From that point on, the upward movement of the steam shaft 58 is no longer restricted by the switch body 48 , but by the lever 34 . Accordingly, it is the position of the intuitive handle 4 , which is operably connected to the lever 34 , that determines whether the steam rate is increased any further or not. This situation, which is depicted in FIGS. 5 and 6 , corresponds to a user control is in its second state.
The steam rate control assembly 30 shown in FIGS. 1-3 is entirely mechanical, i.e. does not comprise any electric or electrically controlled components. Although a (partly) electric steam rate control assembly may be used in alternative embodiments, a mechanical construction is generally preferable as it is more economical in terms of manufacturing costs.
By way of example a number of embodiments of a steam rate control assembly featuring electric components will be described briefly. In one embodiment the steam rate control assembly may comprise an electric pump by means of which a water flow rate in the water channel 10 (see FIG. 1 ) can be controlled. An advantage of an electric pump is that it allows for configurations wherein the flow of water from the water reservoir 12 to the outlet openings 14 in the soleplate 16 of the iron is not gravity-driven. In addition, a pump may allow for much higher steam rates than can be obtained using a merely mechanical steam rate control assembly. Compared to the mechanical embodiments discussed above, the electric pump may effectively replace the valve 32 . Other than that, the described steam rate control assembly 30 may be used without modifications when the flow rate of the pump can be adjusted mechanically, keeping in mind that the steam shaft 58 now adjusts the flow rate setting of the electric pump instead of the position of a valve.
Alternatively, the flow rate setting of the electric pump may be controlled electronically, for example by means of a certain electric signal having a variable voltage or frequency. In that case, the steam rate control assembly may comprise an electronic control unit, e.g. a processor. In addition, the user-control may be an electric control, e.g. an electronic switch, and the handle 4 may be fitted with a displacement sensor or a force sensor to register the displacement of or the force exerted on the handle. In an advantageous embodiment, the electronic control unit may be programmable by the user, such that the user may for example set the steam rates associated with different positions of the user-control precisely as desired. —It is noted that the electric pump, like the water reservoir 12 , need not to be integrated into the housing 2 of the iron, but may be disposed external thereto instead.
Although illustrative embodiments of the present invention have been described with reference to the accompanying drawings, it is to be understood that the invention is not limited to these embodiments. Variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a study of the drawings, the disclosure, and the appended claims. Reference throughout this specification to “one embodiment” or “an embodiment” 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, the appearances of the phrases “in one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, it is noted that the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.
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A steam iron having a bipartite steam rate control, based on a combination of a user-control, which allows a user to consciously set a desired steam rate, and an intuitively operated handle, which may conditionally provide the steam rate control assembly with corrective, energy saving input.
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BACKGROUND OF THE INVENTION
The accelerated non-enzymatic modifications of amino groups of proteins (short- and long-lived), lipids, and nucleic acids by reducing sugars, such as glucose and fructose, play a critical role in the pathogenesis of multiple diseases. These include diabetes mellitus, atherosclerosis Alzheimer's diseases, inflammatory arthritis, osteoarthritis, vascular stiffening, and cataract (Ishibashi Y, et al., 2013; Kroner Z, 2009; Reddy V P, et al., 2006).
The non-enzymatic glycation reaction is also called the Maillard reaction, characterized by a French scientist, Louis Camille Maillard; in 1912 (Reddy V P, et al., 2006). The Maillard reaction is comprised of multiple series of non-enzymatic reactions. In its initial phase, sugars react non-enzymatically with amino groups forming Schiff bases, which subsequently rearrange to form ketoamine or Amadori products. The Amadori product may undergo glycoxidation reaction in the presences of reactive oxygen species (ROS) and reactive nitrogen species (RNS) to form highly reactive dicarbonyl compounds. These include 3-deoxyglucosone, glyoxal, and methylglyoxal. These dicarbonyl compounds react relatively faster with amino groups of proteins, phospholipids, and nucleic acids, and hence result in the formation of a multitude of heterogonous end products, known as advanced glycation end products (AGEs) (Reddy V P, et al., 2002).
Advanced glycation end products (AGEs) formation is a slow process; therefore, AGEs accumulation is predominant on long-lived proteins, including collagens and lens crystallins under physiological milieu (Reddy V P, et al., 2006). This leads to the alteration of biological proteins functions by intra- and inter-molecular cross-links. In addition to this, AGEs form complexes with metal ions, such as Cu+ and Fe++, and hence further accelerate the formation of reactive oxygen and nitrogen species. It has been recognized that diabetes mellitus, which is characterized by hyperglycemia, is a pivotal source of AGEs in human body (Wu C H, et al., 2011; Reddy V P, et al., 2006). It has been stated that hyperglycemic environment increases the formation of AGEs, therefore, AGEs accumulation is several fold higher in diabetic individuals than normal individuals (Ahmed K A, et al., 2009). In addition to their endogenous formation, other sources of these heterogonous moieties in the human body are AGEs-enriched diet, and smoking (Wu C H, et al., 2011; Reddy V P, et al., 2006).
Several AGEs receptors, referred to as receptors for advanced glycation end products (RAGE), involve in signal transduction mechanisms. RAGE a remembers of cell surface immunoglobulin superfamily and are expressed by multiple cell types, including endothelial cells, smooth muscle cells, macrophages, and platelets. They perturb cellular functions, such as formation of intracellular generation of reactive oxygen species, followed by their recognition and interaction with AGEs. In diabetic patients, accumulation of AGEs ligands causes enhanced expressions of RAGE in vasculatures (Goldin A, et al., 2006). The AGE-RAGE interaction plays a pivotal role in the development of chronic complications, such as cardiovascular complications, nephropathy, neuropathy, and retinopathy (Reddy V P, et al., 2006).
Early attention was focused on aminoguanidine, an inhibitor of AGEs formation which sequesters reactive dicarbonyl compounds formed during the Maillard reaction. It also attenuates the oxidative stress, such as trapping of reactive nitrogen species and chelation of transition metal-ions. Although it involves in suppression of AGEs formation through combination of all these mechanisms, the drug was withdrawn from phase III clinical trials because of undesirable side effects (Adisakwattana S, et al., 2012; Reddy V P, et al., 2006). These involve flu-like symptoms, gastrointestinal disorders, deficiency of Vit-B6, and elevated levels of homocysteine (Adisakwattana S, et al., 2012; Gutierrez R M P, et al., 2010; Reddy V P, et al., 2006).
BRIEF SUMMARY OF THE INVENTION
In view of AGEs-mediated extra- and intra-cellular derangements and the associated oxidative stress, much attention has been focused to develop and identify safe and effective advanced glycation end products (AGEs) inhibitors for the treatment of diabetes-associated complications, end-stage renal diseases. This therapeutic approach would be beneficial in preventing and delaying the AGEs-associated late complications of diabetes.
We identified the anti-glycation potential of 6-nitrobenzimidazole derivatives (1-10). Nitrobenzimidazole important pharmacophore in the field of drug discovery. Various benzimidazoles are in clinical use. These include flubendazole and thiabendazole, lansoprezole and omeprazole, and astemizole for the treatment of anthelmintic, antiulcerative, and antihistaminic, respectively (Gurvinder S, et al., 2013). The anti-glycation activity of these derivatives was explored by high-throughput screening method, using fluorescence-based anti-glycation assay (see Table-1). Cytotoxicity evaluation was also carried out against mouse fibroblast (3T3) cell-line by employing MTT-assay. The in-vitro cellular-based mechanistic approaches were also employed to study the effectsof 6-nitrobenzimidazole derivativeson fructose-derived AGE-induced intracellular reactive oxygen species (ROS) production, and associated diminished growth of the hepatocytes (rat hepatocytes, CC1-cell line) via dichlorofluorescin diacetate (DCFH-DA) technique and MTT assay, respectively. Besides their anti-glycation activity, these derivatives were found to be nontoxic and reduced the fructose-derived AGE-mediated intracellular ROS production and impaired proliferation of the hepatocytes.
TABLE 1
In Vitro Anti-glycation Activity and Cytotoxicity of
6-Nitrobenzimidazoles (1-10).
Anti-glycation Activity
Cytotoxicity
%
IC 50 ± SEM
%
Compound
Inhibition
[μM]
Inhibition
3-(6-Nitro-1H-benzimidazol-2-
88.8%
17.7 ± 0.001
35.9%
yl)-1,2-benzenediol (1)
2-(6-Nitro-1H-benzimidazol-2-
88.2%
48.7 ± 0.006
21.1%
yl)-1,4-benzenediol (2)
6-Nitro-2-(3-thienyl)-1H-
81.9%
142 ± 0.014
19.7%
benzimidazole (3)
4-(6-Nitro-1H-benzimidazol-2-
91.2%
71.7 ± 0.008
9.8%
yl)-1,2,3-benzenetriol (4)
2-(6-Nitro-1H-benzimidazol-2-
yl)-1,3,5-benzenetriol (5)
89.2%
109 ± 0.02
4.0%
4-(6-Nitro-1H-benzimidazol-2-
86.0%
25.5 ± 0.000
3.4%
yl)-1,2-benzenediol (6)
4-(6-Nitro-1H-benzimidazol-2-
87.8%
52.4 ± 0.001
37.4%
yl)-1,3-benzenediol (7)
2-(4-Methylphenyl)-6-nitro-
70.8%
192 ± 0.017
59.2%
1H-benzimidazole (8)
6-Nitro-2-(4-nitrophenyl)-1H-
61.7%
114 ± 0.005
45.2%
benzimidazole (9)
4-(6-Nitro-1H-benzimidazol-2-
76.9%
194 ± 0.039
3.6%
yl) phenol (10)
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 depicts the structures of 6-nitrobenzimidazole derivatives, novel identified anti-glycation agents.
FIG. 2A depicts the AGE induced ROS generation in the hepatocytes (CC1-Cell line). The cells were first treated with DCFH-DA and then incubated with 200 μg/mL of AGEs at 37° C. for 24 hours. The specified ROS values are the mean of two independently performed experiments.
FIG. 2B depicts the effect of compound 4, novel identified anti-glycation agent of 6-nitrobenzimidazole derivatives, on fructose-derived AGEs induced ROS formation in the hepatocytes. The cells were initially treated with DCFH-DA at 37° C. for 45 mins and then with the compound 4 at various concentrations, and co-incubated with 200 μg/mL of AGEs at 37° C. for 24 hours. The specified ROS values are the mean of two independently performed experiments.
FIG. 3 depicts the effect of compound 4, novel identified anti-glycation agent of 6-nitrobenzimidazole derivatives, on the hepatocytes growth and proliferation, co-incubated with the 200 μg/mL AGEs. The cells were treated with various concentrations of compound 4 at 37° C. for 24 hours. The specified absorbance is the mean of two independently performed experiments.
DETAILED DESCRIPTION OF THE INVENTION
The current invention is related to the discovery of novel compounds which can inhibit protein glycation process and the associated AGEs formation in hyperglycemia.
Example 1
Glycation of Human Serum Albumin (HSA)
Chemicals: Rutin monohydrate and human serum albumin (HSA, Essential fatty acids free) were purchased from Sigma Aldrich, St. Louis, Mo., USA. Sodium azide (NaN3), dimethyl sulfoxide (DMSO), and D-fructose were obtained from Merck, Darmstadt, Germany. The solutions were prepared under sterile conditions using deionized water at 25° C.
Procedure of the Assay: The glycated HSA was prepared in accordance with a minor modification of the Sattarahmady method (Sattarahmady N., et al., 2007). In brief, HSA (10 mg/mL) was incubated with a supra-physiological concentration (500 mM) of D-fructose to foster the reaction in a 100 mM sodium phosphate buffer (NaHPO4/NaH2PO4), containing 0.1 mM sodium azide (NaN 3 ) under dark and, sterile environment at 37° C. for seven days. Prior to incubation, rutin (reference compound) and 6-nitrobenzimidazole derivatives were added to a reaction mixture to a final concentration of 1 mM. DMSO was used as a solvent (final concentration: 10%) in this assay.
Glycated HSA Detection by Fluorescence Intensity: The glycated HSA formation was measured by AGE-specific fluorescence intensity at 340 nm (an excitation wavelength) and 440 nm (an emission wavelength) using Spectra Max Spectrophotometer (Applied Biosystems, CA, USA).
Estimation of Glycated HSA Percentage Inhibition: The following formula was employed to estimate the percent fluorescence inhibition of glycated HSA.
Percentage Inhibition=(1−Fluorescence of test compounds/Fluorescence of glycated-HSA)×100
Where,
Test compounds=6-Nitrobenzimidazole derivatives
IC50 Value Determination: 6-Nitrobenzimidazole derivatives, which showed moderate to excellent anti-glycation activity, were further tested for their IC50 values by EZ-Fit software.
Results: 6-Nitrobenzimidazole derivatives 1, 2, 4, 6, and 7 exhibited significant anti-glycation activity, with lower IC 50 values as compared to the reference compound, rutin (IC50=70±0.5 μM). Compounds 3, 5, and 8-10 showed a moderate anti-glycation activity, as presented in Table-1.
Discussion: The preliminary findings from the structure-activity relationship (SAR) studies established that the presence of hydroxyl moieties, either away or vicinal to each other on phenyl rings of 6-nitrobenzimidazole derivatives is essential for the anti-glycation activity.
Example 2
6-Nitrobenzimidazole Derivatives Inhibitors of Fructose-Derived AGE-Mediated Intracellular Generation of Reactive Oxygen Species (ROS)
Chemicals: Dichlorofluorescindiacetate (DCFH-DA) probe, hydrogen peroxide (H 2 O 2 ), dimethyl sulfoxide (DMSO; tissue culture grade) and phosphate buffer saline (PBS) were acquired from Sigma, St. Louis, Mo., USA. Black fluorescence 96-well plates (Tissue culture treated) were obtained from Thermo Fisher Scientific, Waltham, Mass., USA.
Procedure of the Assay: Briefly, 6×104 cells/mL cells (normal rat hepatocytes: CC1-Cell line) were seeded on a 96-well plate and kept for 24 hours in an incubator, containing 5% CO 2 at 37° C. Before treating with fructose-derived AGEs, the cells were exposed to serum free MEM (minimum essential medium) for next 24 hours. Initially the cells were incubated with 10 μM DCFH-DA non fluorescent probe, for 45 mins in the dark environment. At the end of the incubation, the cells were washed with 1×PBS twice and were incubated with varying concentrations of the fructose-derived AGE, such as 0, 50, 100, and 200 μg/mL, to investigate the AGEs effect on the production of intracellular ROS in a dose dependent manner. In the next step, the cells were incubated with the different concentrations (24, 33, and 49 μM) of 6-nitrobenzimidazole derivatives, in the presence of AGEs (200 μg/mL) at 37° C. for 24 hours. The control was treated with 0.5% H 2 O2 just before 1 hour prior to halt the incubation period.
Detection of Fluorescence Intensity: The intensity of fluorescence was measured at an excitation 490 nm and an emission 520 nm, using Spectra Max Spectrophotometer (Applied Biosystems, CA, USA).
Estimation of Percentage Inhibition: The inhibition of AGEs-induced intracellular production of ROS in rat hepatocytes incubated with novel anti-glycation agents, 6-nitrobenzimidazole derivatives, was measured by the following formula:
Percentage Inhibition=100−[(Fluorescence of test compound−Fluorescence of blank)/(Fluorescence of control−Fluorescence of blank)×100]
Where,
Blank=Normal rat hepatocytes
Control=Rat hepatocytes treated with 0.5% 11202
Test compound=6-Nitrobenzimidazole derivative
Results: The effect of fructose-derived AGEs on ROS formation was initially determined at different concentrations, such as 50, 100 and 200 μg/mL, using cell permeable non-fluorescent probe, DCFHDA. The probe becomes impermeable following the cleavage by estrases and emits green fluorescence upon oxidation in the presence of intracellular ROS. The increased green fluorescence intensity was observed as the concentration of the AGEs increases, which is associated with the increased production of ROS, as depicted in Table-2.
TABLE 2
Effect of Fructose-derived AGEs on the
Intracellular ROS Production.
Fluorescence
AGEs Concentration
(Average)
200 μg/mL
201.9
100 μg/mL
135.3
50 μg/mL
114.4
HSA
92.3
200 μg/mL
To investigate the anti-glycation effect of 6-nitrobenzimidazole derivatives at the cellular level, the derivatives were selected on the basis of their anti-glycation activity and low cytotoxicity.
Effect of 6-nitrobenzimidazole derivative (24 μM) on the hepatocytes ROS production, co-incubated with fructose-derived AGEs. Initially, the anti-glycation effect of compound 4, belonging to 6-nitrobenzimidazoles, was determined at 24 μM concentration. Compound 4 exhibited moderate activity against ROS production, particularly peroxynitrite (NOO • ) and hydrogen peroxide (H 2 O 2 ), co-incubated with AGE (200 μg/mL), as shown in Table-3.
TABLE 3
Effect of 6-Nitrobenzimidazole Derivative on
AGE-mediated Intracellular ROS Production.
Compound 4
Fluorescence
Percentage
Conc. μM
(Average)
Inhibition
24 μM
138.8
63.6%
33 μM
97.5
89.2%
49 μM
90.7
93.4%
Effect of 6-nitrobenzimidazole derivative (33 μM) on the hepatocytes ROS production, co-incubated with fructose-derived AGEs. The effect of compound 4 on ROS production at 33 JAM concentration, co-incubated with fructose-derived AGE (200 μg/mL), was evaluated. Compound 4 significantly impaired the ROS production in response to AGEs in rat hepatocytes, as shown in Table-3.
Effect of 6-nitrobenzimidazole derivative (49 μM) on the hepatocytes ROS production, co-incubated with fructose-derived AGEs. The effect of compound 4 at 49 μM concentration against the ROS production, co-incubated with fructose-derived AGE (200 μg/mL), was also evaluated. Compound 4 inhibited the AGE-induced ROS production in rat hepatocytes in a remarkably significant manner, as shown in Table-3.
Discussion: The current study revealed the anti-glycation effect of 6-nitrobenzimidazole derivatives at the post-receptor level. The derivative exhibited the anti-glycation effect in a concentration dependant manner. Compound 4 inhibited the interaction of AGEs with RAGE (receptors for advanced glycation end products), and hence impaired the production of the intracellular ROS. RAGE expressions are up-regulated in hyperglycemic environment and play a critical role in the pathogenesis of late complications of diabetes (Barlovic D P, et al., 2011). Therefore, AGE-RAGE nexus is a novel therapeutic approach for preventing and delaying the diabetes associated chronic complications. Newly identified novel compound 4 was found significantly effective in this regard, and hence provide novel therapeutic modality for the prevention of chronic diabetic complications.
Example 3
6-Nitrobenzimidazole Derivatives Inhibitors of Fructose-Derived AGE-Mediated Diminished Growth of the Hepatocytes
Chemicals: Minimum Essential Medium (MEM) with L-glutamine, sodium bicarbonate, trypsin-EDTA, and penicillin-streptomycin were purchased from Sigma, St. Louis, Mo., USA. Sterile, tissue culture treated, round bottom 96-well plates were obtained from Thermo Fisher Scientific, Waltham, Mass., USA. CC1— Cell line (Normal, rat hepatocytes) was obtained from ATCC, Manassas, Va., USA.
Procedure of the Assay: Briefly, 5×10 4 cells/mL (CC1-Cell line: rat hepatocytes) were seeded on a 96-well plate and were initially co-incubated with various concentrations of the AGEs (such as 0, 50, 100, and 200 μg/mL). Fructose-derived AGEs were prepared by mixing 20 mg/mL HSA (Human serum albumin) with 500 mM fructose solution, containing 200 U/mL penicillin, 200 μg/mL streptomycin and 80 μg/mL gentamycin in a 100 mM sodium phosphate buffer. The mixture was incubated at 37° C. for 12 weeks under dark sterile environment. The cells were then incubated with the test compound at different concentrations, such as 24, 33, and 49 μM, co-incubated with 200 μg/mL fructose-derived AGEs in an incubator containing 5% CO 2 at 37° C. for 24 hours. The cells treated with Triton X-100 were used as a blank, while normal cells remain untreated were used as a control. All the treatment with the test compound and the AGEs were completed in serum free medium (SFM).
MTT Assay: Following 24 hours of incubation, the plate was decanted to remove the medium and the cells were washed with 1×PBS. The MTT-dye (50 μL: 2 mg/mL) was then loaded to each well. 200 μL (final reaction volume) was reconstituted by serum free-MEM (Minimum essential media) in a dark environment. The plate was incubated in 5% CO 2 containing incubator at 37° C. for the next 4 hours. At the end of the incubation, the medium was removed and the crystals were dissolved by adding 100 μL DMSO into each well.
Measurement of Absorbance: The intensity of purple colored solution was measured at the wavelength of 540 nm, using Spectra Max Spectrophotometer (Applied Biosystems, CA, USA).
Percentage Inhibition: The inhibition of fructose-derived AGEs-induced impaired growth of the hepatocytes, co-incubated with the test compound, was determined by the following formula:
Percentage inhibition=100−[(Test compound absorbance−BlankAbsorbance)/(Control absorbance−Blank Absorbance)×100]
Where,
Blank=Triton X-100 treated rat hepatocytes
Control=Normal rat hepatocytes
Test Compound=6-nitrobenzimidazole derivatives
Results: The effect of fructose-derived AGEs using various concentrations, such as 50, 100 and 200 μg/mL, was investigated on hepatocytes growth and proliferation, as presented in Table-4. The 200 μg/mL concentration of fructose-derived AGEs had completely impaired the growth and proliferation (62% inhibition) of rat hepatocytes. AGEs at 100 μg/mL and 50 μg/mL inhibited the growth 48% and 28.8%, respectively, in a concentration dependent manner. While the cells co-incubated with HSA (200 μg/mL) were found normal and proliferated at a significant rate, as they were observed in normal untreated cells (see Table-4).
TABLE 4
Effect of Fructose-derived AGEs on the
Proliferation of Rat Hepatocytes.
AGEs
Absorbance
Percentage
Concentration
(Average)
Inhibition
200 μg/mL
0.65
62.4%
100 μg/mL
0.78
48.6%
50 μg/mL
0.98
28.8%
HSA
1.11
15.6%
200 μg/mL
Effect of 6-nitrobenzimidazole derivative (24 μM) on the hepatocytes proliferation, co-incubated with fructose-derived AGEs. Anti-glycation compound 4, belonging to 6-nitrobenzimidazoles class, co-incubated with fructose-derived AGEs (200 μg/mL) at 24 concentration, had showed significant effect on the growth and proliferation of rat hepatocytes (see Table-5).
TABLE 5
Effect of 6-Nitrobenzimidazole Derivative on
AGE-mediated-Diminished Growth of the Hepatocytes.
Compound 4
Absorbance
Percentage
Conc.
(Average)
Inhibition
24 μM
0.91
35.8%
33 μM
0.93
34.3%
49 μM
1.05
22.2%
Effect of 6-nitrobenzimidazole derivative (33 μM) on the hepatocytes proliferation, co-incubated with fructose-derived AGEs. Compound 4 was also evaluated at 33 μM for its anti-AGE effect on the hepatocytes proliferation. Compound 4 significantly restored the growth and proliferation of the cells, co-incubated with fructose-derived AGEs (200 μg/mL) for 24 hours, in a dose dependent manner (see Table-5).
Effect of 6-nitrobenzimidazole derivative (49 μM) on the hepatocytes proliferation, co-incubated with fructose-derived AGEs. The effect of anti-glycation compound 4 of 6-Nitrobenzimidazole at relatively higher concentration (49 μM) was also studied. Compound 4 was found as effective as 33 μM concentration in reducing the toxicity of AGEs (see Table-5).
Discussion: Compound 4 belongs to 6-nitrobenzimidazole class, was found significantly effective at different concentrations (such as 24, 33 and 49 μM) in ameliorating the AGEs-mediated diminished growth of rat hepatocytes. Our recognized anti-glycation agent, compound 4 inhibits the AGE-induced toxicity at the cellular levels, and hence prevents the tissues from prematureaging.
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The invention relates to methods of inhibiting the protein glycation process and the associated formation of Advanced Glycation End products (AGEs) in hyperglycemia by administering 6-Nitrobenzimidazole derivatives. These derivatives were found to be effective not merely against the formation of AGE, but they can inhibit the action of AGEs at post-receptor levels.
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CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present Utility patent application claims priority benefit of the U.S. provisional application for patent Ser. No. 61436187 entitled “MULTI-USE DISASTER RELIEF FAMILY TENT (MDRFT)”, filed on 25-Jan.-2011, under 35 U.S.C. 119(e). The contents of this related provisional application are incorporated herein by reference for all purposes to the extent that such subject matter is not inconsistent herewith or limiting hereof.
FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not applicable.
REFERENCE TO SEQUENCE LISTING, A TABLE, OR A COMPUTER LISTING APPENDIX
[0003] Not applicable.
COPYRIGHT NOTICE
[0004] A portion of the disclosure of this patent document contains material that is subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by anyone of the patent document or patent disclosure as it appears in the Patent and Trademark Office, patent file or records, but otherwise reserves all copyright rights whatsoever.
FIELD OF THE INVENTION
[0005] One or more embodiments of the invention generally relate to tents. More particularly, the invention relates to a tent that may be used in disaster relief situations.
BACKGROUND OF THE INVENTION
[0006] Standard lightweight tents are not suitable for disaster relief due to many factors such as, but not limited to, their thin material, inappropriate size, short life, weak structure, lack of airflow, lack of flexibility, lack of space, etc. Lightweight tents are mostly used for camping and recreational activities. Relief tents are typically made out of heavy material, which increases the heat inside the tent and makes transportation costly and difficult. These tents usually house many people and offer no privacy for families. They are also costly and must be collected after the disaster situation is resolved.
[0007] In view of the foregoing, there is a need for improved techniques for providing a high quality, low cost, lightweight tent made of durable and treated materials with features suitable to provide dignified provisional shelter to families in a disaster or humanitarian aid situation.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] The present invention is illustrated by way of example, and not by way of limitation, in the figures of the accompanying drawings and in which like reference numerals refer to similar elements and in which:
[0009] FIGS. 1A through 1I illustrate an exemplary disaster relief tent, in accordance with an embodiment of the present invention. FIG. 1A is a front perspective view. FIG. 1B is a front view. FIG. 1C is a rear view. FIG. 1D is a rear perspective view. FIGS. 1E , 1 G and 1 H are top plan views, FIG. 1F is a cross sectional side view, and FIG. 1I is a view of an exemplary additional beam;
[0010] FIG. 2 illustrates exemplary openings on sleeves that hold poles, in accordance with an embodiment of the present invention;
[0011] FIG. 3 illustrates exemplary flaps used to attach poles to the tent, in accordance with an embodiment of the present invention;
[0012] FIG. 4 illustrates an exemplary disaster relief tent, in accordance with an embodiment of the present invention;
[0013] FIGS. 5A and 5B are side perspective views of two tents connected at the front walls, in accordance with an embodiment of the present invention. FIG. 5A shows the tents without flaps, and FIG. 5B shows the tents with flaps;
[0014] FIG. 6 is an interior view of exemplary tents connected with flaps on canopies under a large canopy, in accordance with an embodiment of the present invention;
[0015] FIG. 7 illustrates an exemplary large canopy for use over a multiplicity of connected tents, in accordance with an embodiment of the present invention;
[0016] FIG. 8 is a side perspective view of an exemplary disaster relief tent for use as a first aid tent, in accordance with an embodiment of the present invention; and
[0017] FIG. 9 is a side perspective view of an exemplary disaster relief tent for use as a first aid tent, in accordance with an embodiment of the present invention.
[0018] Unless otherwise indicated illustrations in the figures are not necessarily drawn to scale.
SUMMARY OF THE INVENTION
[0019] To achieve the forgoing and other objects and in accordance with the purpose of the invention, a multi-use disaster relief tent is presented.
[0020] In one embodiment a multi-use disaster relief tent includes an outer tent for enclosing a shelter area. The outer tent comprises a roof, a front wall, a rear wall, side walls, and a floor. The roof comprises exterior sleeves extending from the front wall to the rear wall and between the side walls. The front wall comprises two windows and means for detaching at least a portion of the front wall to form a canopy. The rear wall comprises a rear window. At least one of the side walls comprises a side door adjacent the front wall and a side window between the side door and the rear wall. The side door comprises a generally rectangular shape and is operable for opening into a canopy. The floor is removably joined to the outer tent. A plurality of upright poles supports the outer tent in an upright position. The plurality of upright poles is joined to an exterior of the outer tent. A plurality roof poles supports the roof. The plurality of roof poles is encased within the exterior sleeves and each end of the plurality of roof poles is joined to a top end of a one of the upright poles where the roof poles elevate a middle of the roof to mitigate pooling of water.
[0021] In another embodiment a multi-use disaster relief tent includes means for enclosing a shelter area, means for dividing the shelter area into private areas, means for supporting the enclosing means in an upright position and means for supporting a roof of the enclosing means where a middle of the roof is elevated to mitigate pooling of water.
[0022] In another embodiment a multi-use disaster relief tent includes an outer tent for enclosing a shelter area. The outer tent comprises a roof, a front wall, a rear wall, side walls, two air vents each disposed proximate a top corner of the front wall, two air vents each disposed proximate a top corner of the rear wall, and a floor. The roof comprises two exterior sleeves extending from the front wall to the rear wall and three exterior sleeves extending between the side walls. The front wall comprises two plastic windows to provide light and further comprises means for detaching at least a portion of the front wall to form a canopy to provide additional shade and airflow. The rear wall comprises a rear window comprising mosquito netting. The side walls each comprise a side door adjacent to the front wall and a side window between the side door and the rear wall. Each side window comprises mosquito netting. Each of the side doors comprises a generally rectangular shape and is operable for opening into a canopy to provide additional shade and airflow. The floor is removably joined to the outer tent and comprises a bucket style for mitigating entry of water. An inner tent divides the shelter area into private areas. The inner tent is removably joined to the interior of the outer tent. The inner tent comprises three rooms separated by dividers. Each of the three rooms comprises a door comprising mosquito netting and opening into the outer tent. Ten upright poles support the outer tent in an upright position. The ten upright poles each are joined to an exterior of the outer tent. Five roof poles support the roof. The five roof poles are encased within the five exterior sleeves. Each end of the five roof poles is joined to a top end of a one of the upright poles where the five roof poles elevate a middle of the roof to mitigate pooling of water.
[0023] Other features, advantages, and objects of the present invention will become more apparent and be more readily understood from the following detailed description, which should be read in conjunction with the accompanying drawings.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0024] The present invention is best understood by reference to the detailed figures and description set forth herein.
[0025] Embodiments of the invention are discussed below with reference to the Figures. However, those skilled in the art will readily appreciate that the detailed description given herein with respect to these figures is for explanatory purposes as the invention extends beyond these limited embodiments. For example, it should be appreciated that those skilled in the art will, in light of the teachings of the present invention, recognize a multiplicity of alternate and suitable approaches, depending upon the needs of the particular application, to implement the functionality of any given detail described herein, beyond the particular implementation choices in the following embodiments described and shown. That is, there are numerous modifications and variations of the invention that are too numerous to be listed but that all fit within the scope of the invention. Also, singular words should be read as plural and vice versa and masculine as feminine and vice versa, where appropriate, and alternative embodiments do not necessarily imply that the two are mutually exclusive.
[0026] It is to be further understood that the present invention is not limited to the particular methodology, compounds, materials, manufacturing techniques, uses, and applications, described herein, as these may vary. It is also to be understood that the terminology used herein is used for the purpose of describing particular embodiments only, and is not intended to limit the scope of the present invention. It must be noted that as used herein and in the appended claims, the singular forms “a,” “an,” and “the” include the plural reference unless the context clearly dictates otherwise. Thus, for example, a reference to “an element” is a reference to one or more elements and includes equivalents thereof known to those skilled in the art. Similarly, for another example, a reference to “a step” or “a means” is a reference to one or more steps or means and may include sub-steps and subservient means. All conjunctions used are to be understood in the most inclusive sense possible. Thus, the word “or” should be understood as having the definition of a logical “or” rather than that of a logical “exclusive or” unless the context clearly necessitates otherwise. Structures described herein are to be understood also to refer to functional equivalents of such structures. Language that may be construed to express approximation should be so understood unless the context clearly dictates otherwise.
[0027] Unless defined otherwise, all technical and scientific terms used herein have the same meanings as commonly understood by one of ordinary skill in the art to which this invention belongs. Preferred methods, techniques, devices, and materials are described, although any methods, techniques, devices, or materials similar or equivalent to those described herein may be used in the practice or testing of the present invention. Structures described herein are to be understood also to refer to functional equivalents of such structures. The present invention will now be described in detail with reference to embodiments thereof as illustrated in the accompanying drawings.
[0028] From reading the present disclosure, other variations and modifications will be apparent to persons skilled in the art. Such variations and modifications may involve equivalent and other features which are already known in the art, and which may be used instead of or in addition to features already described herein.
[0029] Although Claims have been formulated in this Application to particular combinations of features, it should be understood that the scope of the disclosure of the present invention also includes any novel feature or any novel combination of features disclosed herein either explicitly or implicitly or any generalization thereof, whether or not it relates to the same invention as presently claimed in any Claim and whether or not it mitigates any or all of the same technical problems as does the present invention.
[0030] Features which are described in the context of separate embodiments may also be provided in combination in a single embodiment. Conversely, various features which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable subcombination. The Applicants hereby give notice that new Claims may be formulated to such features and/or combinations of such features during the prosecution of the present Application or of any further Application derived therefrom.
[0031] As is well known to those skilled in the art many careful considerations and compromises typically must be made when designing for the optimal manufacture of a commercial implementation any system, and in particular, the embodiments of the present invention. A commercial implementation in accordance with the spirit and teachings of the present invention may configured according to the needs of the particular application, whereby any aspect(s), feature(s), function(s), result(s), component(s), approach(es), or step(s) of the teachings related to any described embodiment of the present invention may be suitably omitted, included, adapted, mixed and matched, or improved and/or optimized by those skilled in the art, using their average skills and known techniques, to achieve the desired implementation that addresses the needs of the particular application.
[0032] It is to be understood that any exact measurements/dimensions or particular construction materials indicated herein are solely provided as examples of suitable configurations and are not intended to be limiting in any way. Depending on the needs of the particular application, those skilled in the art will readily recognize, in light of the following teachings, a multiplicity of suitable alternative implementation details.
[0033] A preferred embodiment of the present invention and at least one variation thereof provides a multi-use disaster relief family tent (MDRFT) that is a lightweight dome style tent for disaster and humanitarian relief. Many preferred embodiments provide low cost, high quality and dignified provisional shelter to families in disasters and humanitarian situations.
[0034] FIGS. 1A through 1I illustrate an exemplary disaster relief tent, in accordance with an embodiment of the present invention. FIG. 1A is a front perspective view. FIG. 1B is a front view. FIG. 1C is a rear view. FIG. 1D is a rear perspective view. FIGS. 1E , 1 G and 1 H are top plan views, FIG. 1F is a cross sectional side view, and FIG. 1I is a view of an exemplary additional beam. In the present embodiment, the tent comprises improvements and features that may be applied to improve existing tent frames to enable the tent to be more suitable for use in disaster relief and humanitarian aid situations. For example, without limitation, the size, quality, and strength of steel and fiberglass poles are increased, special lightweight materials are used, and various features are added. In order to provide shelter with dignity, the tent is designed to offer as much shade and airflow as possible, protection from mosquitoes, and enough space for a family of ten people. Those skilled in the art, in light of the present teachings, will readily recognize that a multiplicity of other suitable and desirable features may be implemented in alternate embodiments such as, but not limited to, storage compartments, privacy screens, locking capabilities, ventilation systems, windows, etc. The preferred materials used are high quality, resistant to the elements, and are treated to be more resistant to the sun and fire. The tent can be connected to other tents, which offers the flexibility for the tent to be used in different applications such as, but not limited to, as a first aid tent, a school, a community center, a command center, etc.
[0035] Referring to FIGS. 1A and 1B , the tent comprises an outer tent 101 and a detachable inner tent 103 offering three rooms 105 separated by dividers 107 , as depicted in FIGS. 1E , 1 G, and 1 H, and a living area 109 , which can also be used as sleeping space if necessary. Each room has an individual door to satisfy different cultural needs where males and females sleep in separate rooms. In alternate embodiments the tent may comprise multiple inner tents. In the present embodiment, the material of inner tent 103 is preferably breathable polyester; however, alternate materials may be used such as, but not limited to, nylon, cotton etc. Rooms 105 of inner tent 103 comprise individual doors with mosquito netting that may be closed by various means including, but not limited to, zippers, hook and loop material, snaps, buttons, ties, etc. Referring to FIGS. 1A , 1 C and 1 D, back corners 111 of the tent are stretched to allow more sleeping space in rooms 105 located at the sides of the tent. In alternate embodiments of the present invention, the front corners can be stretched and enlarged as well to provide more space. In other alternate embodiments only the front corners may be stretched, and in yet other alternate embodiments none of the corners may be stretched.
[0036] Referring to FIGS. 1A through 1D , the structure of the tent in the present embodiment comprises ten straight steel poles 113 around the tent. Steel poles 113 may be replaced, in alternate embodiments, with rods made out of almost any material found in the disaster area such as, but not limited to, wood or iron or may be made out of any other suitable material such as, but not limited to, fiberglass, aluminum, plastic, etc. Steel poles 113 are connected to five fiberglass poles 115 on the roof of the tent by fittings 117 . Fittings 117 can be made of various different materials such as, but not limited to, plastic, aluminum, other metals, fiberglass, etc. Furthermore, the roof poles in alternate embodiments may be made of various different materials including, but not limited to, aluminum or plastic. In the present embodiment, poles 115 are encased in sleeves to connect poles 115 to the tent material, as shown by way of example in FIG. 2 . The roof is elevated in the middle to generally prevent water from pooling on the roof. There is preferably an additional fiberglass beam 119 , shown in FIG. 1I on the ceiling of the tent for extra support in heavy rain. Additional beam 119 on the ceiling can also be used to position an extra pole using means 118 , for example, without limitation, a wood pole or any other material found in the disaster area, to provide extra support in case of snow accumulation on the roof of the tent. This additional beam may not be included in some alternate embodiments. In the present embodiment, steel poles 113 are attached to the tent with plastic grips 121 and two flaps 123 with eyelets that may be used to attach guy lines to the tent, shown by way of example in FIG. 3 . The tent is secured to the ground with steel pegs on the end of each steel pole 113 . Loops are included in the present embodiment at the bottom of the tent between steel poles 113 to secure the tent to the ground with extra steel pegs; however, these loops may not be included in some alternate embodiments. The tent is also preferably secured with two guy lines (not shown) per steel pole 113 that attach to flaps 123 and are secured to the ground with steel pegs.
[0037] In the present embodiment, the design allows for airflow through the tent, a fast exit in case of emergency, and protection from mosquitoes. A front wall 125 of the tent can be unzipped into a canopy 127 that can be opened for extra shade and airflow. The tent also comprises two side doors 129 , one on each side, which are rectangular for fast evacuation in case of emergency. Side doors 129 provide more airflow throughout the tent and may also open up to into canopies to provide extra shade. The tent comprises three small windows 131 with mosquito netting for more ventilation, one on the rear wall, one on the left side and one on the right side. Additionally the tent has two small windows 133 in the front sealed with plastic to allow light into the tent when the tent is completely sealed due to rain or cold weather. The tent also comprises four air inlet vents 135 in the corners for ventilation. The tent is totally sealable with mosquito netting allowing continuous airflow and can also be sealed completely when canopies and windows are closed. All doors and windows have extra buttons and loops to enable them to be closed in case the zippers fail. Additionally, all zippers have pullers to allow for faster opening in case of emergency. Those skilled in the art, in light of the present teachings, will readily recognize that a multiplicity of alternate and suitable configurations of doors and windows may be implemented in alternate embodiments of the present invention. For example without limitation, the tent may comprise more or fewer windows or more or fewer doors, doors may not be opened into canopies, etc. In one alternate embodiment, rather than having sealed plastic windows to provide light a plastic skylight may be provided or the windows with mosquito netting may also comprise clear plastic flaps that may be closed to seal these windows. In other alternate embodiments, only the front wall of the tent has a door or only the front wall and the back wall have doors. In yet another alternate embodiment, the tent comprises a door on the front wall and one side door. In the present embodiment, the door canopies have attachable flaps, as shown by way of example in FIG. 4 ; however, alternate embodiments of the present invention may not include flaps for the canopies of the doors.
[0038] Referring to FIG. 1B , in the present embodiment, the floor of living area 109 is a bucket style floor 137 to generally prevent water from entering the tent. Floor 137 is detachable and comprises loops in order to enable floor 137 to be used as a tarp, if necessary, for more shade. Flaps 139 are provided around the tent to enable rainwater to slide away from the tent, generally preventing rainwater from entering the tent. Alternate embodiments may be implemented without a bucket style floor or with no flaps around the tent.
[0039] In the present embodiment, the preferred dimensions for the tent to shelter a family of ten people are 520 cm in length by 272 cm in height by 520 cm in width, without including the size of the canopies of front wall 125 and side doors 129 . However, in alternate embodiments, the tent can be built in smaller or larger sizes. In the present embodiment over 80% of the ceiling of outer tent 101 is more than 2 m in height to enable most people to comfortably stand in the tent; however, the height of the ceiling may vary in alternate embodiments of different sizes. In the present embodiment, the outer tent is preferably made of a resistant Polyester Oxford 210D with Rip-stop fabric 300D and water protection.The preferred water protection is PU4000MM. The material is also preferably treated with a fire retardant treatment according to CPAI-84. The material resists temperatures from −15 degrees centigrade to 45 degrees centigrade. In alternate embodiments of the present invention, the fabric of the tent may be various different fabrics including, but not limited to, any Oxford fabric denier with or without Rip-Stop, cotton, canvas, polyester, etc. In the present embodiment, the material of the tent may be made in one of two colors, white or light blue. These colors keep the tent cooler and clearly distinguish the tent as a humanitarian tent in a disaster or humanitarian situation. In alternative embodiments of the present invention any other color can be used depending on the situation. The material of outer tent 101 is preferably silver coated and has a UV 50 for extra protection against the sun; however, this coating may not be included in some alternate embodiments.
[0040] FIG. 2 illustrates exemplary openings 201 on sleeves 203 that hold poles 115 , in accordance with an embodiment of the present invention. In the present embodiment, openings 201 , which are located at the points where poles 115 cross, facilitate water drainage from the roof of the tent. Since the roof is higher in the middle the rain water flows downwards through the openings preventing water pooling on the roof.
[0041] FIG. 3 illustrates exemplary flaps 123 used to attach poles 113 to the tent, in accordance with an embodiment of the present invention. In the present embodiment, eyelets 301 in flaps 123 enable guy lines to be attached to flaps 123 and secured to the ground with steel pegs. These guy lines add stability to the tent; however, the guy lines may be omitted in some embodiments.
[0042] FIG. 4 illustrates an exemplary disaster relief tent, in accordance with an embodiment of the present invention. In the present embodiment, the tent comprises two doors 401 on one side and a door 403 on the front wall. Door 403 is shown opened into a canopy 405 with flaps 407 to protect against rain and wind. When two tents are connected to each other flaps 407 are able to form a tunnel, as shown by way of example in FIG. 5B .
[0043] FIGS. 5A and 5B are side perspective views of two tents connected at the front walls, in accordance with an embodiment of the present invention. FIG. 5A shows the tents without flaps 501 , and FIG. 5B shows the tents with flaps 501 . In the present embodiment, the tents are connected at the ends of canopies 503 formed from doors 505 at the fronts of the tents. The connecting mechanism in this embodiment is with loops and bottons in the middle and on each corner of the canopies but other connecting means can be used such as zippers, Velcro, etc. A rectangular side door 507 of one tent is shown sealed with mosquito netting, and a rectangular side door 509 of the other tent is shown closed. The tents may also be connected to other tents with the canopies formed by side doors 507 and 509 . Referring to FIG. 5B , flaps 501 protect against rain and wind and make a tunnel between the two tents.
[0044] A preferred use for many preferred embodiments of the present invention is as disaster and humanitarian family relief tents. However, due to the flexible design of many preferred embodiments those skilled in the art, in light of the present teachings, will readily recognize that a multiplicity of alternate and suitable uses for preferred embodiments of the present invention exist including, but not limited to, first aid tents, school modules, community centers, command centers, offices, etc.
[0045] FIG. 6 is an interior view of exemplary tents connected with flaps 601 on canopies 603 under a large canopy 605 , in accordance with an embodiment of the present invention. In the present embodiment, this configuration of the tents may be used for different uses such as, but not limited to, as a school or as a community center. Large canopy 605 enables the tents to feel more connected and provide added protection from the elements.
[0046] FIG. 7 illustrates an exemplary large canopy 605 for use over a multiplicity of connected tents, in accordance with an embodiment of the present invention. In the present embodiment, a large steel pole 701 is located in the center of canopy 605 to hold up canopy 605 .
[0047] In an exemplary application as a school module, four tents are connected to each other without divisions making a total of four classrooms. This configuration preferably comprises one bucket style floor for each tent, which may or may not comprise flaps on the doors to protect from rain. This configuration also may or may not have a large canopy added to cover the four tents for extra protection. The school can be made smaller or larger by removing or adding connected tents. A community center may also be formed with a same or similar configuration.
[0048] FIG. 8 is a side perspective view an exemplary disaster relief tent for use as a first aid tent, in accordance with an embodiment of the present invention. In the present embodiment, the tent comprises an inner tent without dividers to form one large room 801 that can hold multiple patients. A front wall 803 in the present embodiment does not comprise a door.
[0049] FIG. 9 is a side perspective view an exemplary disaster relief tent for use as a first aid tent, in accordance with an embodiment of the present invention. In the present embodiment, the tent comprises an inner tent with a divider 901 to separate a patient room 903 for one or more patients from an office 905 for first aid personnel such as, but not limited to, doctors, paramedics, nurses, etc. Multiple tent of this configuration may be connected to each other at a canopy 907 to make any number of rooms for patients, with or without flaps 909 on canopies 907 .
[0050] In an alternative embodiment of the present invention the structure of the tent may be made of a minimum of four large poles made of a flexible material such as, but not limited to, fiberglass arcing over the tent from one side to the other and crossing each other on the roof rather than the steel poles and five roof poles.
[0051] Those skilled in the art, in light of the present teaching will readily recognize that a multiplicity of suitable features may be included in some alternate embodiments of the present invention. For example, without limitation, in one alternative embodiment of the present invention, solar panels can be positioned on the roof to provide electrical power to the tent. Some alternate embodiments may use this electrical power for conveniences such as, but not limited to, lighting, fans, heat, air conditioning, etc. Some alternate embodiments may comprise kitchen areas. Other alternate embodiments may comprise pouches, storage compartments or shelves built into the walls for storing items such as, but not limited to, personal items, medical supplies, food, etc. Yet other alternate embodiments comprise loops or hooks for hanging items such as, but not limited to, lanterns, fans, IV bags, etc.
[0052] Having fully described at least one embodiment of the present invention, other equivalent or alternative methods of providing multi-use tents according to the present invention will be apparent to those skilled in the art. The invention has been described above by way of illustration, and the specific embodiments disclosed are not intended to limit the invention to the particular forms disclosed. For example, the particular implementation of the tents may vary depending upon the particular type of application for which they are to be used. The tents described in the foregoing were directed to humanitarian aid implementations; however, similar techniques are to provide tents for non-humanitarian purposes such as, but not limited to, base camps for mountain climbing or military applications. Non-humanitarian implementations of the present invention are contemplated as within the scope of the present invention. The invention is thus to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the following claims.
[0053] Claim elements and steps herein may have been numbered and/or lettered solely as an aid in readability and understanding. Any such numbering and lettering in itself is not intended to and should not be taken to indicate the ordering of elements and/or steps in the claims.
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A multi-use disaster relief tent includes an outer tent for enclosing a shelter area. The outer tent comprises a roof, a front wall, a rear wall, side walls, and a floor. The roof comprises exterior sleeves. The front wall comprises two windows and means for detaching at least a portion of the front wall to form a canopy. At least one of the side walls comprises a side door adjacent the front wall and a side window. The side door is operable for opening into a canopy. A plurality of upright poles supports the outer tent. The plurality of upright poles is joined to an exterior of the outer tent. A plurality roof poles supports the roof. The plurality of roof poles is encased within the exterior sleeves and each end of the plurality of roof poles is joined to a top end of a one of the upright poles.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a gas-powered auxiliary engine and universal mount assembly for a multi-wheeled vehicle, e.g., a bicycle. More particularly, the invention relates to an engine assembly which selectively, drivingly engages the rear wheel of a bicycle, is readily attached to and detached from almost any size and/or style of bicycle, and includes uncomplicated safety features.
2. Description of the Prior Art
The present invention provides an extremely light weight and uncomplicated auxiliary engine and universal mounting assembly therefor, so that the engine may be readily attached to most any type of bicycle or other multiwheel manually powered vehicle, with minimum difficulty. Furthermore, the instant invention provides: brake actuated kill switches for the engine, an important safety feature; a mounting assembly which spring urges the engine into a non-driving, fail safe configuration, another important safety feature; and a cable operated clutch arrangement which provides engagement of the engine drive wheel with the rear tire of the bicycle, unlike prior art auxiliary engine assemblies. A further safety feature may be a key operated engine kill switch associated with the bicycle seat, for example. The Dead Man switch assures that the engine is disabled automatically should the rider become separated from the bicycle. Additionally, the present invention provides a unique drive wheel made of polyurethane material or the like, the drive wheel providing a vibration reducing, cushioned mount for the engine when the drive wheel is engaged with the bicycle driven wheel, the assembly also serving as a vibration dampener to greatly reduce the effects of vibration not only from the engine but also from the terrain over which the bicycle is ridden; furthermore, the assembly has been found quite effective in maintaining a secure engagement of drive wheel and driven wheel even when the terrain over which the bicycle is ridden is very rough, or even of washboard configuration.
It is well known in the prior art to equip an existing pedal powered bicycle with an auxiliary engine. However, a number of distinct disadvantages are encountered with prior art motorized bicycles. Some examples are: mounting of the engine requires substantial modification to the conventional bicycle; the installation of prior art auxiliary engines is time-consuming and expensive for the average novice mechanic; and such assemblies often require an engine of special design, an unnecessary additional expense.
The prior art of motorized bicycles discloses the practice of having a drive arrangement that includes a motor driven friction pulley, such as a friction wheel, or the like, which drive arrangement contacts the surface of a rear tire of a bicycle. Further, such prior art discloses the practice of a spring biasing the auxiliary engine so as to maintain driving contact between the friction device and the bicycle tire. Further, prior art motorized bicycle assemblies generate considerable difficulties in their installation onto existing bicycles, especially in view of their complicated driving arrangements. These installations necessitate extensive modification to the bicycles onto which they are to be mounted.
Examples of prior art auxiliary engine assemblies for conventional, pedal driven bicycles will now be discussed in some detail.
U.S. Pat. No. 1,158,311, issued Oct. 26, 1915 to George S. Schunk, shows an auxiliary engine for bicycles, pivotally mounted behind the bicycle seat, but requiring a spring arrangement to force the engine drive wheel onto the rear tire of the bicycle. No provision whatsoever is made to readily and easily remove the engine drive wheel from the bicycle rear tire.
U.S. Pat. No. 2,491,076, issued Dec. 13, 1949 to Mario Benazzoli, discloses an auxiliary engine for a bicycle including an engine spring slung mounted beneath the pedal cranks and no provision is made for displacing the drive roller or wheel of the engine from the bicycle rear tire.
Schunk and Benazzoli exemplify prior art attempts which fail to keep an auxiliary engine drive wheel off of the rear tire.
U.S. Pat. No. 2,586,082, issued Feb. 19, 1952 to Sanzio P. V. Piatti, discloses an auxiliary engine with a drive wheel, spring urged into engagement with a bicycle wheel, rather than away from the bicycle wheel. A cable and hand control are employed to move the engine and roller away from the driven bicycle wheel, not toward it as in the instant invention. Thus, there is no shock absorbing action for the engine when disengaged, since there is no spring support for the engine in this attitude, again unlike the present invention. Furthermore, should the cable support system of Piatti fail, then the engine and drive wheel will fall onto the bicycle wheel, thus creating a potentially very unsafe situation. Additionally, Piatti addresses the problem of heat transfer and admits the problem of the tire becoming overheated. However, the solution taught in Piatti is to provide an engine drive wheel with an internal cooling fan, which is completely inapposite to the instant invention, where an engine carriage also functioning as a heat sink reduces heat transfer to the drive wheel to an acceptable minimum.
U.S. Pat. No. 3,339,659, issued Sep. 5, 1967 to Walter A. Wolf, discloses two auxiliary engine powered cones which are frictionally engaged with a bicycle tire 80, by reason of both the weight of the power unit plus the forces exerted by a pair of tension springs, urging the cones into firm engagement with the bicycle rear tire 122. As pointed out in this patent (column 1, lines 16 to 29) considerable difficulty has been encountered in the prior art in maintaining a uniform and efficient driving engagement of the auxiliary engine drive wheel to the bicycle tire; the problem is solved by use of the present invention, without need of complex drive wheels and spring assemblies, as will be detailed below.
U.S. Pat. No. 3,966,007, issued Jun. 29, 1976 to Ralph L. Havener, et al., discloses an auxiliary electric motor for a bicycle with a battery and battery casing disposed between the rider's legs. Both weight and location of components proposed by Havener, et al., generate obvious problems.
U.S. Pat. No. 4,200,164, issued Apr. 29, 1980 to Frank S. Pearne, represents an improvement over the art as just discussed, disclosing an auxiliary engine for a bicycle which is readily mounted onto and detached from the bicycle. However, the Pearne arrangement requires an extra handle for operating the engine and, similarly to the art set forth above, requires a tension spring arrangement to urge the engine drive wheel onto the bicycle rear tire, in direct contradistinction to the present invention, which utilizes spring force to urge the drive wheel away from the tire. Again, and as is the case with other prior art discussed above, the proposed arrangement likely will not keep the drive wheel in engagement when the bicycle is ridden over rough terrain of any kind, and Pearne completely fails to address the matter of heat transfer problems.
In summary, the art exemplifies prior attempts to provide an adequate auxiliary engine for a bicycle, all of which fail to force an auxiliary engine drive wheel off of the rear tire, rather than onto it, and provide selective engagement of the engine drive wheel with a bicycle tire, without need of utilizing anything other than a cable tension assembly and the force of gravity.
None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed.
SUMMARY OF THE INVENTION
The present invention relates to an auxiliary, gas-powered engine assembly for use on a bicycle. The assembly has a small internal combustion engine mounted on a carriage assembly which is supported from one side of the rear axle of the bicycle, and a driven polyurethane friction wheel for propelling the rear bicycle tire. The assembly includes a compression spring mechanism within the carriage which is arranged, dimensioned and configured to force the engine drive wheel off of the bicycle rear tire, rather than onto it. A two legged (one short, one long), horizontally moved, adjustable strut associated with the carriage is selectively manipulated by a manually operated clutch control, against the force of the spring, whereby the drive wheel is moved from a non-operative, fail safe attitude under urging of the compression device mechanism, to an operative position, against the urging of the spring, with a polyurethane or like material drive wheel in engagement with the bicycle rear tire. The output engine drive arrangement includes a multiple tooth cog or sprocket, interfit within the drive wheel; it has been found that a non-rigid fit provides a self adjusting, flexible drive mechanism for overcoming imperfectly formed tires, wheels or both. This improves efficiency and reduces wear and tear on the entire drive train. It is believed that these real and annoying imperfections, resulting from the ordinary course of manufacture, generate the drive wheel to bicycle tire engagement problems which were attempted to be addressed by prior art proposals.
Additionally, the present invention provides auxiliary engine controls (clutch and throttle) which are bicycle handle mounted for ready access, and a pair of momentary engine kill switch arrangements which kill the auxiliary engine as soon as either or both of the bicycle hand brakes are touched for braking. Additionally, a dead man switch arrangement may be provided, associated with the bicycle operator, for example, which serves to turn off the engine anytime the rider becomes separated from the bicycle.
As for the clutch assembly for engaging the engine drive wheel with the bicycle rear tire, it has been found that a conventional, pivoted or rachet derailleur control system may be employed to move the engine drive wheel into engagement with the bicycle rear wheel in a controlled manner, against the urging of a compression spring arranged to force the drive wheel off of the bicycle rear tire.
Accordingly, it is a principal object of the invention to provide an auxiliary, gas powered engine assembly for use on a bicycle, having a mounting carriage in which the engine drive wheel is spring urged away from the driven tire, and employing a Bowden cable assembly or the like for forcing the drive wheel into engagement with the driven wheel, against the urging of the spring.
It is another object of the invention to provide an auxiliary gas powered engine assembly which can be installed quickly and easily on a conventional bicycle.
It is a further object of the invention to provide an auxiliary gas powered engine assembly for propelling a conventional bicycle which may be installed without modifying the bicycle in any manner.
It is an object of the invention to provide an auxiliary engine assembly for a bicycle or the like having the engine drive wheel assembled in a fail safe configuration, there further being engine momentary kill switch mechanisms associated with the bicycle conventional hand brakes for disabling the engine when braking is initiated.
It is a further object of the invention to provide an auxiliary engine assembly for a bicycle or the like including a drive wheel having a somewhat self adjusting interfit with the engine output shaft, thus to accommodate irregularities in the driven wheel and/or tire and yet provide a firm, non-slip interengagement of drive wheel to driven wheel.
It is another object of the invention to provide an auxiliary gas powered engine assembly for propelling a bicycle including brake operated, momentary kill switches which disable the engine's power as soon as either or both brakes are actuated, but permits the engine to reignite by a compression start as soon as both brakes are released. So long as the engine drive wheel and the bicycle driven, or rear, wheel are engaged, the engine may be repeatedly stopped and started while the bicycle is moving, simply by compressing and releasing the brake controls of the bicycle.
It is a further object of the invention to provide a bicycle having an auxiliary gas powered engine assembly which is portable and very easily installed on and removable from a bicycle without need of any special parts or tools.
It is yet another object of the invention to provide a bicycle having an auxiliary gas powered engine and mounting assembly which is constructed with inexpensive parts.
Still another object of the invention is to provide a bicycle having a gas powered engine assembly that is completely safe and reliable in operation, there being fail safe mounting and braking components integral with the assembly.
It is an object of the invention to provide a bicycle with an auxiliary gas powered engine and mounting assembly having uncomplicated adjusting mechanisms allowing for universal assembly of the engine onto most any type, style and size of bicycle, tricycle or the like.
Yet a further object of the invention is to provide an auxiliary gas powered engine and carriage assembly which may be employed as a power take off subassembly, and including inherent, integral fail safe mechanisms.
It is an object of the invention to provide improved elements and arrangements thereof in an apparatus for the purposes described which is inexpensive, dependable and fully effective in accomplishing its intended purposes.
These and other objects of the present invention will become readily apparent upon further review of the following specification and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an elevational, somewhat diagrammatic, side view of a bicycle having a gas-powered engine assembly mounted on the rear bicycle frame in accordance with the preferred embodiment of the present invention;
FIG. 2 is an enlarged scale, fragmentary, partially exploded perspective view of the essential engine mounting components;
FIG. 3 is an enlarged scale, diagrammatic, perspective view of an aluminum extrusion carriage for mounting the engine;
FIG. 4 is an enlarged scale, partially fragmentary elevational side view showing the arrangement of parts with the engine drive wheel disengaged from the bicycle rear wheel;
FIG. 5 is a view similar to FIG. 4, but showing the engine drive wheel engaged with the bicycle rear wheel;
FIG. 6 is a rear, elevational view showing the mounting of the engine and carriage assembly of the rear drive wheel of the bicycle;
FIG. 7 is an exploded, perspective view showing a drive cog, drive wheel and weight carriage bearing; and
FIG. 8 is a mechanical and electric wiring diagram showing areas for hand controlled and safety/convenience devices for the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Before explaining in detail the present invention, it is to be understood that the invention is not limited in its application to the details of construction and arrangement of parts illustrated in the accompanying drawings, since the invention is capable of other embodiments and of being practiced or carried out in various ways. By way of example only, it should be understood that the present invention, while specifically disclosed as being used with a conventional bicycle, could also be used with any one of a wide variety of other wheeled vehicles, ranging from tricycles to wheelchairs. Also it is to be understood that the phraseology and terminology employed herein is for the purpose of description and not limitation.
FIG. 1 shows a conventional bicycle 10 equipped with a gas powered engine assembly 12 according to an embodiment of the present invention. The bicycle 10 includes a frame 14, a front wheel 16, a rear driving wheel 18, handlebars 20, a seat 22, a control handle cable assembly 24 (see FIGS. 4 and 5), and pedals 26. The bicycle 10 may be of the usual lightweight, multispeed type, or a dirt bike, BMX bike, or any one of the wide variety of bicycles currently marketed and used, and is entirely of conventional construction, apart from the gas powered engine assembly 12 discussed herein.
As illustrated in FIG. 1, the gas powered assembly 12 of the bicycle 10 includes an inverted, U-shaped carriage or rack 28, preferably an aluminum extrusion, and a gas powered, small, lightweight engine 30. Aluminum is the preferred material making up the carriage 28, because the material is lightweight and acts as an excellent heat sink for engine cooling. The engine 30 may be a readily available, very small and lightweight, 2 cycle engine; a 49 cc displacement engine is quite suitable, both from weight and cost considerations. The construction and arrangement of the carriage 28 provides sufficient space for auxiliary components, such as fuel cells, luggage, lights, spare parts, etc. (not shown).
With further reference to FIGS. 1 and 2, carriage 28 is secured to seat post 32 of bicycle frame 14 by a U-shaped mounting clamp 34 secured to the seat post 32 by a U-bolt and bracket assembly 36 and a pair of nuts 38, 38 (these may be lock nuts, if desired) threaded onto the ends of the U-bolt, as indicated by the exploded view, FIG. 2. In turn, the forward end of carriage 28 is pivotally mounted on or attached to clamp 34 by a nut and bolt assembly (not shown) inserted through holes 40, 40 of clamp 34, and a selected pair of opposed holes 42 formed through the forward end of carriage 28. Four sets of holes 42, for example, may be provided, one series of the set of four being shown in FIG. 2. A number of such mounting holes are provided so that the invention may fit a wide variety of bicycles. The attachment of carriage 28 to seat post 32 is clearly seen in FIG. 1.
Turning now to FIGS. 1, 6 and 7, it is seen that the small, 2 cycle, 49 cc (for example) engine is mounted on the rear of carriage 28 as by one or more nut and bolt assemblies 44. Engine 30 includes an output shaft 46, having a multitoothed cog wheel 48 at the outer end thereof, which is interfit within a polyurethane drive wheel 50. Conveniently, drive wheel 50 is hollowed out to comfortably receive the cog wheel 48. On the opposite side, wheel 50 is bored to receive a weight carriage bearing 52 and the assembly is held in place by an adjustable nut and bolt assembly 54. In turn, the assembly 54 is mounted through a bracket 56, which is securely bolted to carriage 28 as is shown at 58. Adjustability of the just described assembly is provided by a lock nut 60, which may be adjusted inwardly or outwardly as needed to allow drive wheel 50 a bit of play so as to accommodate any irregularities in the bicycle rear tire and wheel 18. With such flexibility, it has been found that the tire 18 and polyurethane wheel 50 combine to provide a shock absorbing motor mount. Heat transfer and/or abrasive wear patterns and/or unproductive friction are minimized and even eliminated, yet drive wheel 50 is maintained in firm engagement with rear wheel 18, even when the bicycle is ridden over rough, washboard type terrain. Thus, the present invention is completely unlike prior art devices, where the drive wheel often becomes readily and annoyingly separated from the bicycle driven wheel when an auxiliary engine is employed.
The operation and engagement of drive wheel 50 with rear wheel 18 of the bicycle 10 will become readily apparent from the following discussion and reference to FIGS. 1, 4 and 5. In FIG. 4, drive wheel is seen disengaged from rear wheel 18 of the bicycle, and in FIG. 5, the drive wheel 50 is engaged with the bicycle rear wheel 18. The carriage 28 is supported from a rear axle bracket 62 by a somewhat Y shaped strut assembly 64; conveniently, the lower end of the Y strut may be mounted to an axle bracket hole normally provided for mounting a child's seat behind the bicycle rider. Alternatively, a small bracket secured to the bicycle frame could be employed to mount the lower end of Y strut 64 (not shown). Y strut 64 includes a major arm 66 and a short pivot arm 68, which is pivotally mounted to both the carriage 28 and the major arm 66, as is indicated at 70, 72, respectively. Major arm 66 is universal, as it may be adjusted in length, by being constructed in two sections, for example Major Arm 66, adjusted and then is bolted together as is generally indicated in FIG. 1, at 74.
Mounted within carriage 28 is an axial compression device comprising a compression spring 76 with front and rear seats 78 and 80, respectively, all contained within a tube 82, conveniently fabricated from a length of PVC pipe. Alternatively, compression spring 76 could be an otherwise conventional gas strut. The upper end 84 of major arm 66 is urged against seat 80 by the control handle cable assembly 24, an otherwise conventional derailleur assembly, in a preferred embodiment. The handlebar clutch control of derailleur 24 is shown at 86, in FIG. 8. The conventional adjusting tension mount for cable 24 is seen at 88, FIGS. 4 and 5, and the tension mount may be mounted in any one of three holes 90, provided along carriage 28, as may be required for proper operation of derailleur 24, which is used to raise and lower carriage 28 so that drive wheel 50 is out of engagement with rear wheel 18 of bicycle 10 (FIG. 4) or in driving engagement with rear wheel 18 (FIG. 5). The clutching of derailleur 24 causes end 84 of arm 66 to move to the right, in the sense of FIGS. 4 and 5, thus pivoting arm 66 counterclockwise, and reducing the effective length distance of the carriage 28 with respect to the bicycle axle of the rear wheel, from the distance A, seen in FIG. 4, to the distance B, as seen in FIG. 5. Furthermore, the compression strength of spring 76 may be adjusted by a cam 88 having opposed flats. Rotation of the cam 88, 180 degrees from the position shown in FIGS. 4 and 5 will reduce the compression strength of the spring 76 somewhat. Adjustment of the compression strength of spring 76 also may be desirable when drive wheel 50 is replaced with a different diameter wheel, as will be explained below.
As can be appreciated from FIG. 1, the entire carriage may be raised about its forward pivot at 40 (FIG. 2) by simply disconnecting the lower end of major arm 66 from the bicycle rear axle and raising the arm 66. Conveniently, the arm may be propped upon the rear tire 18, so as to access parts beneath carriage 28. This is desirable when one wishes to change the drive wheel to a different size, for example. Since the drive wheel 50 is only held in place by compression between the cog 48 and bearing 52, unthreading of bolt 54 allows an easy change of a drive wheel 50. Drive wheel 50 may be sized from one and one-half inches, for high torque capability, up to three inches in diameter or more, for higher cruising speed, allowing for a variety of applications.
An inspection and comparison of FIGS. 3 and 6 reveals that removal and replacement of the drive wheel 50 is accomplished very easily. With the engine and drive wheel in the disengaged configuration shown in FIG. 4, the nut and bolt assemblies indicated at 58 may be removed. As can be appreciated from FIG. 6, sufficient clearance is provided such that drive wheel bracket 56 is moved to clear the depending skirt portion of carriage 28, whereupon the entire assembly is removed from drive cog wheel 48; the parts 48 and 50 are merely slidably interfitted together, as was explained above. One may then very easily inspect parts for wear or damage, replace the carriage bearing 52 if needed, change the drive wheel 50 if worn or if another sized wheel is desired, for reasons explained above, or perform any needed adjustments. Replacement of the subassembly including wheel 50, bearing 52, assembly 54 and bracket 56, is also very easily done, simply by fitting drive wheel 50 over cog 48, aligning bracket 56, and reattaching the nut and bolt assemblies 58.
Referring now to FIG. 8, additional safety features of the invention will be discussed. By now, it can be readily appreciated that any failure in derailleur 24 would only cause the engine and carriage to raise upwardly to a non-driving wheel engaged attitude, or a fail safe position, unlike prior art assemblies. The invention is extremely lightweight, incidentally; in a preferred embodiment, a 49 cc engine with carriage 28 and all associated hardware weighs only about eleven and one-half pounds. The engine weighs six and one-half pounds and all the other components combined weigh but five pounds. Also, since the invention is connected to the bicycle at just two points, rear axle bracket and seat post, it may be readily attached and removed from the bicycle 10 in short order. In FIG. 8, momentary kill switches are indicated, one at 90 for the front brake, and one at 92 for the rear brake. These switches are wired to ground the ignition of the engine to the bicycle frame immediately upon an associated brake lever being depressed or just touched. Conversely, when both brakes are released and assuming the bicycle is underway, the engine 30 will be restarted by a compression start, due to the action of bicycle wheel against the engine drive wheel 50. This invention thus provides for virtually instantaneous engine on-off-on operation, with minimal effort on the part of the operator.
As an option for even further safety, a key switch 94, operable by a key 93, could be provided, beneath seat 22 as is indicated in FIG. 8, for example. Key 93 is connected by a belt loop, partially indicated at 95, to the operator. Thus, should the rider fall off of the bicycle 10 or even try to stand on the pedals 26, the key 93 readily separates from switch 94, permitting switch 94 to close and thus disable the engine 30.
Finally, an engine throttle control 96 is shown. This is conveniently mounted on the right handlebar, near the grip, as is indicated in FIG. 8.
It has been determined after extensive experimentation that the engine drive wheel 34 should preferably be fabricated of a polyurethane material. However, it is to be understood that different material types and sizes of friction wheels may be used in practicing the instant invention.
The assembly 12 operates in various modes, such as at an idle speed while the bicycle 10 is traveling on a level surface, or at a higher throttle setting as when climbing a hill. It is to be understood that the starting of the engine 30 is a compression start situation where the engine 30 is started by the forward movement of the bicycle 10 on a level or downhill situation. When the operator desires to terminate a power assisted operation, the brakes are actuated, which effectively kills the engine 30 to terminate its power assisted operation. This termination of power also produces compression braking. The clutch may then be disengaged and the entire carriage assembly will have no interaction with normal pedal operation of the bicycle.
It is to be understood that the present invention is not limited to the embodiments described above, but encompasses any and all embodiments within the scope of the following claims. For example, the instant invention discloses a single strut assembly 64 associated with the rear wheel 18, but it is obvious that an additional strut member could be added on the opposite side of strut 64 to reinforce the support of the assembly 12 on the bicycle 10.
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A gas-powered engine assembly is mounted on a carriage supported over the rear tire of a conventional bicycle. The assembly includes a small internal combustion engine supported on the carriage and a driven polyurethane friction wheel for propelling the rear bicycle tire. The assembly includes a compression spring within the carriage tending to move the carriage and engine drive wheel out of engagement with the bicycle rear tire, and a cable and clutch arrangement for lowering the drive wheel into engagement with the bicycle rear tire. A horizontally moveable strut associated with the carriage is selectively manipulated by a manually operated clutch control, whereby the engine drive wheel is moved from an operative to a non-operative position. The output engine drive arrangement includes a multiple tooth cog located within a pocket formed in the drive wheel, for providing a flexible drive mechanism for accommodating possible defects such as a slightly out of round and/or unbalanced tire and the like. The polyurethane drive wheel is adjustably mounted over the tire to accommodate irregularities in the driven bicycle tire, and thus assure constant engagement with the bicycle tire. Brake and operator associated momentary switches for the engine are provided for safety.
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[0001] Subject of the present invention is a new process for the preparation of nitroorotic acid (II), which is obtained by nitration of orotic acid (I) according to the following reaction scheme:
[0000]
[0002] Reaction Scheme 1
[0003] Nitroorotic acid is a key intermediate in the synthesis of dipyridamole, which is an active ingredient in Persantin® (sole active ingredient) and Aggrenox® (in combination with acetylsalicylic acid). Persantin® is a medicament used for preventing thrombosis and embolic events, Aggrenox® is a medicament used for the prevention of stroke.
[0004] Several other processes for preparing nitroorotic acid are known from the prior art.
[0005] A synthesis of the potassium salt of nitroorotic acid starting from orotic acid is described by M. Bachstez in Ber.dtsch.chem.Ges. 63 (1930) 1000. The synthesis was done only in a small laboratory scale, using a mixture of nitric and sulphuric acid as reagent. Most of the educt did either not react or decomposed, so that as a consequence, the yield of the product was very low.
[0006] In Ann. 456 (1924) 165, H. Biltz and E. Kramer describe the preparation of nitroorotic acid in form of yellow needles decomposing at 236° C. by reacting orotic acid with fuming nitric acid, without giving any details about the reaction conditions or the yield.
[0007] F. G. Fischer and J. Roch (Ann. 572 (1951) 217) describe a laboratory scale process for preparing the potassium salt of nitroorotic acid using 4-methyl-2-thiouracil as starting material. They obtained the product in a yield of 50-55%.
[0008] Both R. Behrend and O. Roosen (Ann. 251 (1889) 238) and H. Biltz and M. Heyn (Ann. 413 (1916) 110) describe the synthesis of the potassium salt of nitroorotic acid starting from methyluracil in laboratory scale.
[0009] Presently, the nitroorotic acid needed for the manufacture of Persantin is produced by a large scale process based on nitration and oxidation of 6-methyluracil using fuming nitric acid. For the nitration step, the reaction temperature has to be maintained in a range of between 20° C. and 30° C. The oxidation step requires a temperature of up to 100° C.
[0010] Due to the high reaction temperature during the oxidation step, the whole reaction system may become instable, if the temperature is not controlled properly. The technical measurements, which are needed to regulate the system and to control the temperature in order to avoid e.g. decomposition, are highly expensive. The maximum yield of the current process is about 80% of the theory. A byproduct of this process is nitrogen dioxide, a toxic gas. For each mole of the starting material 6-methyluracil, 6 moles of nitrogen dioxide are set free, which have to be disposed of properly.
AIM OF THE INVENTION
[0011] The aim of the present invention is to overcome the problems linked to the present process for producing nitroorotic acid, to improve the known process for preparing nitroorotic acid, particularly with respect to both economic (yield, costs and availability of starting material) and ecologic (protection of the environment) aspects of a large scale process, and to enhance the safety (protection of employees) of the process.
SUBJECT OF THE INVENTION
[0012] Subject of the present invention is a new improved process for the preparation of nitroorotic acid via nitration of orotic acid according to reaction scheme
[0013] Surprisingly, it has been found that the process according to the invention solves the problems related to the present synthetic route.
[0014] Most importantly, the development of toxic nitrous fumes such as nitrogen dioxide can completely be avoided by using the process according to the invention, because instead of fumed nitric acid as according to the prior art, 65% nitric acid is used. This reduces pollution as well as risks, and is an advantage with respect to safety and environment protection.
[0015] Furthermore, the educt is readily available in good quality and at a reasonable price, because it is widely used (several 100 tons per year) as an ingredient for animal food. The reagents are very common and in expensive chemicals, too, so that the costs of goods are low.
[0016] Energy costs are reduced, since the reaction temperature is significantly lower than in the process known from the prior art. Furthermore, due to the lower reaction temperature particularly during the oxidation step, no expensive technical measurements for system regulation and temperature control are needed.
[0017] Bothe, the yield of the product (about 90%) and its purity are high resp. very high. This enhances the profitability of the process, and simultaneously reduces the efforts needed for purification.
[0018] Contrary to the known process, even at production scale, the process of invention does not require any special equipment for controlling the reaction due to safety issues.
[0019] Another advantage of the process according to the invention is that it can be conducted as a semi-batch process, i.e. that the educt (orotid acid) does not need to be added all at once, but may be added portionwise to the mixture of sulphuric and nitric acid. The next portion of orotic is added to the reaction mixture only after the previous portion was transformed into the product. This procedure, which was not possible according to the old method, helps to control the reaction in a simple, but effective way. Energy (and temperature) peaks can thus be avoided.
[0020] Additionally, after quenching the reaction mixture in water, the nitroorotic acid can be isolated as free acid, and thus, does not need to be set free from its salt prior to the next reaction step in the synthesis of dipyridamole, thereby avoiding additional working steps and saving time.
[0021] Furthermore, after quenching the reaction mixture in water, the water-containing product thus obtained may be used directly in the next step without that it is necessary to dry it previously, thereby saving time and costs. Due to the very high purity, the product of the subsequent step in the synthesis of dipyridamole does not need to be isolated.
[0022] Finally, the sulphuric acid used in the reaction can be recycled directly, after concentration. This is both reducing costs and protecting the environment.
DETAILED DESCRIPTION OF THE INVENTION
[0023] Nitroorotic acid (II) is produced by nitration of orotic acid (I) according to reaction scheme 1.
[0024] As the reagent, a mixture of concentrated sulphuric acid and concentrated (but not fuming) nitric acid is used. Preferably, the concentration of the sulphuric acid is 98% and the concentration of the nitric acid is 65%. Usually, sulphuric acid and nitric acid are mixed in a molar ratio of between 1:1 and 6:1. Preferably, the ratio of sulfuric acid to nitric acid is about 3:1 (in mole).
[0025] The nitration is carried out at a temperature of about 40-80° C. The preferred reaction temperature is about 40-60° C.; even more preferred is a reaction temperature of about 50-60° C.
[0026] No ethanol is added to the reaction mixture.
[0027] The nitroorotic acid such produced is susceptible to form hydrates.
EXAMPLE
[0028] Nitroorotic acid (obtained via nitration of orotic acid) With cooling below 50° C., 420 ml (7.68 mol) concentrated sulphuric acid (H 2 SO 4 , approx. 98%) were added to 169 ml (2.56 mol) 65% nitric acid (HNO 3 ). Then, 200 g orotic acid (1.28 mol; purity 99.64%) were added portionwise. The reaction mixture was heated to 50-55 ° C. under stirring for 3 hours.
[0029] After completion of the nitration, the reaction mixture was allowed to cool down to ambient temperature (about 10-15 ° C.), and was then poured into 800 ml of water under cooling below 30° C. While the resulting mixture was cooled to about 0-10 ° C., it was stirred slowly. The precipitated product was filtered off and washed with a small amount of cold water, and then dried at about 50-60 ° C.
[0030] Yield: 230 g (90%) based on waterfree material
[0031] Purity: 98.89% (HPLC)
[0032] Decomposition above 230° C.
[0033] MS (ESI): 202 (MH + )
[0034] 13 C-NMR (500 MHz, D 2 O, ppm): 122.6, 150.1, 151.7, 158.3, 162.7
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Subject of the present invention is a new improved process for the preparation of nitroorotic acid via nitration of orotic acid.
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CROSS-REFERENCE TO RELATED APPLICATION
[0001] This is a non-provisional application which claims priority to the provisional application Ser. No. 60/741,980 filed Dec. 2, 2005 and commonly owned by the same inventor. The above noted application is incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] This warning tube relates to traffic control devices and more specifically to temporary and portable roadway markers. A unique aspect of the present invention is a semi-rigid collapsible tube that accepts a variety of traffic controls.
[0003] Transitioning from horse drawn equipment where drivers had longer time to react to traffic and road conditions to engine powered vehicles where drivers have less time for judging traffic and road conditions, traffic control devices have increased in use and drivers have become dependent upon them. Traffic control devices operate at fixed locations, primarily intersections as in stop lights, at changes in a road as in grade signs, and at temporary locations as in construction sites.
[0004] Construction sites arise when a portion of a road gets repaired due to age, damage, or other causes. Construction often disturbs the road surface and traffic must be detoured around the construction site. Markers are installed at the entrance to a construction site and along the site. The markers inform traffic of the site and guide the traffic around the site. The markers are generally high enough for an automobile driver to see them and they have reflective or even illuminated portions for use at night or during inclement weather. The markers are spaced around and along a site to create an apparent line to guide drivers along the site.
[0005] Eventually, construction projects finish along a road. Part of closing a construction site involves removing the markers. As the markers are made to withstand the elements and minor brushes by vehicles, the markers are generally collected for reuse. Recovered markers are then stacked or collapsed for storage until used again. Though a construction site has been described, markers also see use for guiding traffic around accidents and for closing a road due to weather. Markers are used by construction companies, police and fire departments, highway departments, and related entities.
DESCRIPTION OF THE PRIOR ART
[0006] As engine powered vehicles have traveled roads for some decades, various markers and traffic control devices have been developed. The devices position a light, sign, or reflector for a driver to see while the devices themselves are constructed to allow for storage and reuse. For example, there is a form of contractible traffic guide, as shown in the Whims U.S. Pat. No. 1,250,064. This particular device is used on a road, and is held by a chain, through a spring, into its erected condition. Presumably, the spring holds the guide erect, but when the guide bends, the spring contracts, the chain becomes more flexible, and the guide collapses.
[0007] The patent to Shoemaker, Jr., U.S. Pat. No. 3,132,624, is upon a collapsible signal device. The sleeve assembly can be collapsed, as when not in use. While this is a collapsible signal device, its flexible sheet turned into a cone is a different structure from the present invention.
[0008] The patent to Andrew God, U.S. Pat. No. 3,847,784, shows a metal pipe with spaced flexible portions. This is one of those metal pipes, with flexible corrugated portions that allow for bending the pipe, when applied by a plumber. Thus, the pipe can be fitted to the condition of usage.
[0009] The patent to Glitz, et al, U.S. Pat. No. 5,230,296, is upon a retractable parking aid. This is an expandable device, made of polypropylene, likely of similar material as used in constructing the present invention, but it is used primarily as a parking aid. Apparently, when one parks into a garage, and encounters this device, one ceases further movement into the garage. Though not like the present invention, it does utilize a corrugated tube.
[0010] The patent to Bent, et al., U.S. Pat. No. 6,014,941, shows a traffic delineator. This device is used upon the highway to help direct and channel traffic, around construction sites, and the like. This particular device defines the use of a handle at the center of the cylinder which is not the present invention. The handle is further defined as sized so as to pass through a circular opening in the base of the device.
[0011] The patent to Kramer, Jr., U.S. Pat. No. 6,102,078, shows rubber tubing with axially spaced annularly corrugated flexible segments. This device includes rubber tubing of a specified length. The device then has included in its structure the positioning of an end length of a sleeve of uncured rubber over an end portion of a forming mandrel. The end sleeve is not the structure of the present invention.
[0012] The patent to Brown, et al., U.S. Pat. No. 6,182,600, defines a traffic channeling device. This device is a cone-shaped channeling member that can be expanded, or contracted, so as to reduce its size. In its expanded stage, it is vertically erect. But, it can be contracted into the lowest portion, for storage. The present invention is not structured as telescoping or nesting portions as in this particular patent.
[0013] Finally, the published application to Kuo, No. US2002/0073912A1, is also upon a traffic delineator. This device is a cylinder, which has reflective sheets provided at the upper end, grip holes proximate to its bottom end, and a series of holes for flags.
[0014] The present art overcomes the limitations of the prior art. That is, in the art of the present invention, a warning tube accepts a variety of signals upon the upper end and has corrugations that permit bending of the tube. Existing devices collapse in various ways but do not retain a bent shape and carry a traffic signal or fitting. However, using a corrugated tube in the present invention provides a new means to display traffic signs and markers along a road to drivers.
[0015] The present invention overcomes the difficulties of the prior art. The warning tube has components that collapse and disassemble for storage and for transport. The warning tube also bends to withstand brushes with vehicles and to retain the shape of the road ahead of the warning tube. For instance, a construction site that forces drivers to bear right may have the warning tube bent to the right for a visual cue to the turn ahead. Combined with other devices, the warning tube readily integrates into existing traffic control programs.
SUMMARY OF THE INVENTION
[0016] The warning tube is a device that guides drivers around an obstacle such as a construction site. The warning tube has a base with a neck, a tube having corrugations and a sleeve at the lower end and an opposite neck at the upper end, and a variety of signals or fittings temporarily placed into the neck of the tube. The fittings include a cap over the neck, a reflector, a light, and a traffic sign like a yield sign, among other things. The upper neck has a reflective band so the tube can be used without any fitting in the neck. The tube is stored and transported collapsed as it occupies the least volume. After the sleeve is placed upon the neck of the base, the tube is expanded upward to position a fitting at a height visible to drivers. If desired, the tube is bent at an angle to indicate the anticipated direction of the road ahead of the warning tube. The corrugations attain the bend and retain the warning tube in the bent shape.
[0017] Preferably, the neck of the tube has a round cross section that accepts round fittings. Alternatively the neck of the tube has a polygonal section that receives complementarily shaped fittings. The polygonal section prevents inadvertent turning of a fitting. In an alternate embodiment, the warning tube has a corrugated cone shape with a light upon the base. In another alternate embodiment, the warning tube has its sleeve fit upon a flashlight which transmits light through the tube. The present invention has usage at construction sites, accidents, and like places where traffic must rerouted differently from the normal flow and direction.
[0018] The principle object of this invention is to provide a warning tube made as a corrugated or bellows like structure, capable of flexibly being bent or curved to different angles in order to furnish more observable display of a cautioning or other warning.
[0019] A further object of this invention is to provide a staple base, with a corrugated means extending upwardly therefrom, which may be painted a caution orange, or be illuminated, in order to furnish a warning to nearby observers.
[0020] Still another object of this invention is to provide a warning device with inherent flexibility that allows for it usage for thoroughly cautioning any nearby drivers, workers, walkers, or other personnel, of the existence of an emergency condition.
[0021] These and other objects may occur to those skilled in the art upon review of the summary of the invention as provided herein, and upon undertaking a study of the description of its preferred embodiment, in view of the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] FIG. 1 shows the present invention when collapsed;
[0023] FIG. 2 shows the present invention when extended;
[0024] FIG. 3 shows an exploded view of the present invention;
[0025] FIG. 3A has a view of the cap;
[0026] FIG. 3B has a view of the light feature;
[0027] FIG. 3C has a view of the sign feature;
[0028] FIG. 3D has a view of the reflector feature;
[0029] FIG. 3E has a top view of the neck in a hexagonal shape;
[0030] FIG. 3F has a top view of the neck in a rounded corner rectangular shape;
[0031] FIG. 3G has a top view of the neck in an oval shape;
[0032] FIG. 4 describes the present invention extended and bent into a non-linear shape;
[0033] FIG. 5 describes an alternate embodiment of the tube of the present invention;
[0034] FIG. 6 illustrates a conically shaped alternate embodiment of the present invention; and,
[0035] FIG. 7 shows the tube of the present invention in cooperation with a flashlight.
[0036] The same reference numerals refer to the same parts throughout the various figures.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0037] The present invention overcomes the prior art limitations by providing an extensible tube that bends into and retains a shape while carrying a traffic sign or directional indicator. Turning to FIG. 1 , the warning tube of the present invention 1 begins with a base 2 , here shown round. The base has a planar flat shape to reduce the incidence of tipping the present invention when in place to direct traffic. Generally centered upon the base, a neck 3 , here shown in phantom, extends upwards from the base. The neck has a smaller width than the base and hollow cylindrical construction. Coaxial with the neck, a tube 4 extends upwards from the base. The tube has a sleeve 5 at one end and its own neck 6 at the opposite end. The sleeve has a diameter slightly larger than the neck 6 of the base but does fit snugly upon that neck. Above the sleeve, the tube has a series of mutually parallel and coaxial corrugations 7 . The corrugations are accordion like and generally extend outside of the perimeter of the sleeve and the neck of the tube. The corrugations generally expand and extend the tube longitudinally. The tube has a plurality of corrugations provided so the tube reaches a certain height when extended, as later shown in FIG. 2 . Above the corrugations, the tube has its own neck 6 . This neck has the same diameter as the sleeve 5 . This neck is generally hollow and admits the cap 8 . The cap has a round lid 9 of greater diameter than this neck which allows the cap to rest upon the top of this neck. Upon the exterior surface of the lid, the cap has a handle 10 used to remove the cap for insertion of a traffic signal or fitting later described. Opposite the handle, the cap has a shank 11 depending beneath the lid. The shank has a diameter slightly less than this neck which allows for a snug fit of the cap into this neck. FIG. 1 shows the present invention in a collapsed state for storage and transport.
[0038] When the present invention is used, the tube is extended upwards or generally away from the base as shown in FIG. 2 . As described previously, the present invention has a base with an upstanding neck. A sleeve fits the tube upon the neck and thus orients the tube upright. The tube is then pulled which opens the corrugations 7 and lengthens the tube 4 . Within the neck of this tube, a cap 8 closes the tube.
[0039] The present invention has additional features shown in FIG. 3 . As a user desires a semi-permanent installation of the invention, the neck 3 of the base 2 , the sleeve 5 , the neck 6 of the tube 4 , and the shank 11 of the cap 8 have cooperating threaded holes for a bolted connection. Using the holes, a user connects the tube 4 to the base 2 , and the cap 8 or other traffic signal or fitting control to the neck 6 of the tube 4 . The cap 8 has a generally cylindrical form with a hollow shank 11 , a lid 9 upon one end of the shank, and a handle 10 upon a diameter of the lid opposite the shank as shown in FIG. 3A . Along with the cap, the present invention has additional traffic signals or fittings that fit within the neck 6 of the tube 4 . A lighted traffic fitting 12 appears in FIG. 3B where a dome light is connected to the lid upon a shank. The light may illuminate constantly or intermittently as needed by the user. Besides the light fitting 12 , a sign 13 to direct or to inform traffic can be placed upon the neck of the tube. The sign has an approved traffic control shape, color, and indicia generally perpendicular to the lid with a shank beneath shown in FIG. 3C . The sign here shown is the attention sign common in continental Europe but other traffic indicators are possible. Opposite the light, a reflector 14 can be placed upon the neck 6 of the tube 4 , shown in FIG. 3D . Unlike the lighted traffic control which emits light, the reflector returns the light from vehicle headlights that falls upon the reflector in the direction of the vehicle. The reflector allows for illumination of a traffic control in the absence of battery or utility service to the present invention. The reflector attaches perpendicular to the lid and opposite the shank. The aforementioned traffic fittings generally have a threaded hole through the shank that allows bolting of the traffic fitting against inadvertent rotation in this neck 6 .
[0040] Alternatively, the traffic controls may not rotate because of the shape of the neck. FIGS. 3E, 3F , and 3 G show polygonal, rounded corner rectangular, and oval cross sections of the neck of this tube, respectively. These cross sections permit insertion of a complementarily shaped shank from a traffic control. As these cross sections have corners or asymmetric dimensions, a traffic fitting may not turn when placed into the neck of this tube.
[0041] Returning to the assembled present invention, FIG. 4 shows how the tube 4 bends into a desired shape. The corrugations expand upon one side and compress upon the opposite side to make a generally right angle bend. Generally the tube 4 bends in the direction of the compressed corrugations. The bends can mimic the shape of the road ahead of the warning tube. For example, FIG. 4 shows two bends in the tube which indicate the road ahead makes a right turn and then a left turn. As described previously, the present invention has a base with an upstanding neck over which a sleeve connects. The sleeve is the lower end of a tube having coaxial corrugations. The corrugations 7 are accordion like in that pulling the corrugations away from the base lengthen the tube as needed and permits the tube to bend. Opposite the sleeve, the tube has its own neck 6 into which a cap 8 or traffic fitting 12 , 13 , 14 inserts its shank 11 .
[0042] Similar to FIG. 4 , the tube of the present invention may have a straight portion 4 a without corrugations as shown in FIG. 5 . The straight portion adds to the length and rigidity of the tube. FIG. 5 shows a flat base with a sleeve 5 connected to the neck 3 of the base 2 . The tube 4 then has a first portion 7 a of corrugations coaxial with the tube generally near the sleeve and a then a straight section 4 a midway up the tube. The straight section has no corrugations and does not bend. The straight section has a generally round shape with a diameter that of the inside diameter of a fold. The straight section generally has a length of at least one diameter. The tube continues with a second portion 7 b of corrugations, opposite the first portion 7 a , and ending in the neck 6 of the tube 4 . Various traffic fittings and the cap can be placed in the neck as previously described.
[0043] The present invention may see use in many places and for many purposes. FIG. 6 shows an alternate embodiment of primarily the tube 4 b . In this alternate embodiment, the warning tube has a conical shape 15 where the corrugations progressively decrease in diameter away from the base 2 . The narrowest diameter 6 a of the warning tube is opposite the base and has a ring shaped cap 8 a . The base has a light 16 centered within the neck in this alternate embodiment. The light is generally battery powered however, solar power and utility power are alternate energy sources for the light. The tube 4 a is generally translucent to make this alternate embodiment visible to drivers. The neck has a generally round shape of a diameter slightly less than the largest diameter of the conical warning tube.
[0044] The tube of the present invention may also cooperate with other devices. FIG. 7 shows an alternate embodiment of the present invention in cooperation with a flashlight 16 . In this alternate embodiment, the tube 4 begins with a sleeve 5 . The sleeve is a hollow cylinder having a diameter compatible with a flashlight. The flashlight is generally handheld and powered by two D size batteries or equivalent. Above the sleeve, the tube has a plurality of coaxial corrugations 7 as previously described. The corrugations are also made of an opaque material however some light may leak at the outermost edge or ring where a corrugation flexes. Above the corrugations, the tube has a neck 6 of hollow cylindrical construction. Opposite the corrugations, the neck 6 has an opening 17 that emits light generated by the flashlight and transmitted through the tube. The opening may have a lens 17 a as desired. The material for the sleeve and the neck has an opaque outer surface to prevent leakage of light from the tube and a reflective inner surface to direct light out of the tube. In this alternate embodiment, the sleeve connects to the rim of the flashlight sized to match the diameter of the sleeve. In a further alternate embodiment, the sleeve connects to one end 18 a of an adapter 18 . The opposite end 18 b of the adapter has an aperture that fits the rim of a flashlight. Adapters are provided having one end sized for the sleeve and a plurality of opposite ends sized for different size and shape flashlight rims.
[0045] It should be understood that in the various corrugated or bellows like structures as provided herein, where they have a hollow segment interiorly, it is more than likely that any type of illuminating device, such as a light, may be included therein, with battery or other electrical connection, in order to furnish illumination either throughout the tube, at its upper end, as previously described, or at other locations where it may be desirable. For example, in the sleeve portion 5 of the tube, there may be a lamp and batteries provided therein, to illuminate that location, which may be either transparent, or tinted with an orange or florescent orange, or any other material that may transmit light. The light may extend upwardly and show through the coaxial corrugations 7 , as can be understood. Or, such lighting may be included in the shank or neck portion 11 , or at the neck 6 , in order to furnish illumination therethrough. Or, as described in the application, the illumination may be at the upper signs 13 , or reflectors 14 , to furnish greater lighting and cautionary illumination therethrough. This is similar to what has been described in FIG. 3B .
[0046] From the aforementioned description, a warning tube has been described. The warning tube is uniquely capable of collapsing for storage and attaining a bent shape to indicate the road ahead of the present invention. The warning tube and its various components may be manufactured from many materials, including, but not limited to singly or in combination, polymers, polyester, polyethylene, polypropylene, polyvinyl chloride, nylon, ferrous and non-ferrous metals and their alloys, and composites.
[0047] Variations or modifications to the subject matter of this invention may occur to those skilled in the art upon review of the invention as described herein. Such variations if within the spirit of this development, is intended to be encompassed within the scope of the invention as described. The depiction of the invention in the drawings, and its description in the preferred embodiment, are set forth for illustrative purposes only.
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The warning tube guides drivers around an obstacle such as a construction site. Beginning with a base that has a neck, the warning tube has corrugations like an accordion, a sleeve at the lower end, its own neck at the upper end, and a variety of fittings temporarily placed into the neck. The fittings include a cap, a reflector, a light, and a traffic sign like a yield sign, among other things. After the sleeve is placed upon the neck of the base, the tube is expanded upward to position a fitting visible to drivers. The corrugations of the tube are bent at an angle to indicate the direction of the road ahead of the warning tube.
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CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation-in-part of application Ser. No. 07/595,625 filed on Oct. 5, 1990, abandoned, which is a continuation of application Ser. No. 07/444,917 filed on Dec. 4, 1989.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to polyesters useful for facilitating the separation of blood serum or plasma from the cellular portion of blood.
2. Description of the Related Art
The polyesters of the invention are conveniently formulated into a partitioning composition for use in a blood collection vessel in which the blood sample is subjected to centrifugation until the cellular portion and serum or plasma are completely separated. The physical and chemical properties of the partitioning composition are such that a continuous, integral seal is provided between the separated blood phases, thereby maintaining separation of the phases after centrifugation and simplifying removal of the serum or plasma from the blood collection vessel. The high volume testing of blood components in hospitals and clinics has led to the development of various devices to simplify the collection of blood samples and preparation of the samples for analysis. Typically, whole blood is collected in an evacuated, elongated glass tube that is permanently closed at one end and sealed at the other end by a rubber stopper having a diaphragm which is penetrated by the double-tipped cannula used to draw the patient's blood. After the desired quantity of blood is collected, the collection vessel is subjected to centrifugation to yield two distinct phases comprising the cellular portion of the blood (heavy phase) and the blood serum or plasma (light phase). The light phase is typically removed from the collection vessel, e.g., via pipette or decantation, for testing.
It has been proposed heretofore to provide manufactured, seal-forming members, e.g., resilient pistons, spools, discs and the like, in blood collection vessels to serve as mechanical barriers between the two separated phases. Because of the high cost of manufacturing such devices to the close tolerances required to provide a functional seal, they have been supplanted by fluid sealant compositions. Fluid sealant compositions are formulated to have a specific gravity intermediate the two blood phases sought to be separated, so as to provide a partition at the interface between the cellular and serum phases. Such compositions typically include a polymer base material, one or more additives for adjusting the specific gravity and viscosity of the resultant composition, and optionally, a network former. Representative prior art fluid sealant compositions include: styrene beads coated with an anti-coagulant (U.S. Pat. No. 3,464,890); silicone fluid having silica dispersed therein (U.S. Pat. No. 3,780,935); a homogenous, hydrophobic copolyester including a suitable filler, e.g., silica (U.S. Pat. Nos. 4,101,422 and 4,148,764); a liquid α-olefin-dialkylmaleate, together with an aliphatic amine derivative of smectite clay or powdered silica (U.S. Pat. No. 4,310,430); the reaction product of a silicone fluid with a silica filler and a network former (U.S. Pat. No. 4,386,003); and a mixture of compatible viscous liquids, e.g., epoxidized vegetable oil and chlorinated polybutene, and a thixotropy-imparting agent, e.g., powdered silica (U.S. Pat. No. 4,534,798).
Ideally, a commercially useful blood partitioning composition should maintain uniform physical and chemical properties for extended time periods prior to use, as well as during transportation and processing of blood samples, readily form a stable partition under normal centrifugation conditions and be relatively inert or unreactive toward the substance(s)in the blood whose presence or concentration is to be determined.
Inertness to substances sought to be determined is a particular concern when blood collection vessels are used for therapeutic drug monitoring (TDM), which is assuming an increasingly important role in drug treatment strategies. TDM enables the administration of drugs in the appropriate therapeutic ranges, established through the accumulated experience of clinicians, and consequently reduces the number of patients receiving dosage levels that are either below detection limits or toxic. Administration of drugs under TDM allows one to take into account such factors as drug tolerance developed with passage of time, presence of multiple physical disorders and synergistic or antagonistic interactions with other therapeutic agents. Among the drugs recommended for administration under TDM are those having dangerous toxicity with poorly defined clinical endpoint, steep dose-response curve, narrow therapeutic range, considerable inter-individual pharmacokinetic variability or non-linear pharmacokinetics, as well as those used in long term therapy or in the treatment of life-threatening diseases. By way of example, the evaluation of blood levels of a number of tricyclic antidepressant compounds, such as imipramine or desipramine, in relation to an empirically established therapeutic range is reported to be particularly useful in the treatment of seemingly drug-refractive depression. TDM is likewise used to monitor the dosage of anticonvulsant drugs, such as phenytoin and phenobarbital which are administered in the treatment of epilepsy, antitumor drugs, such as methotrexate, and other more commonly prescribed drugs, including, but not limited to digoxin, lidocaine, pentobarbital and theophylline.
Reports of recent studies on the effect of blood partitioning compositions on drug concentrations in serum and plasma indicate that care must be taken in the selection of polymeric materials which come into contact with the blood samples obtained for drug assay. See, for example, P. Orsulak et al., Therapeutic Drug Monitoring, 6:444-48 (1984) and Y. Bergqvist et al. Clin. Chem., 30:465-66 (1984). The results of these studies show that the blood partitioning compositions provided in blood collection vessels may account for reduced serum or plasma values, as a result of drug absorption by one or more components of the composition. The reported decreases in measured drug concentrations appears to be time-dependent. One report concludes that the observed decreases in drug concentrations may effectively be reduced by minimizing the interval between collection and processing. Another report recommends that blood samples be transported to the laboratory as soon as possible, with processing occurring within 4 hours. A commercially useful blood collection vessel, however, must produce accurate test results, taking into account routine clinical practices in large institutions, where collection, transportation and processing of blood samples may realistically take anywhere from about 1-72 hours.
British patent 685,649 teaches a process for the preparation of polyesters made by reacting succinic acid having an open chain hydrocarbon radical containing from 18 to 26 carbon atoms directly joined to at least one of the methylene groups and an organic compound having two esterifiable hydroxyl groups. There is no teaching of polyesters made by reacting other dicarboxylic acid components such as a second dicarboxylic acid having from 4 to about 12 carbon atoms and/or a third dicarboxylic acid component having from about 5 to about 25 mole percent of an aliphatic dicarboxylic acid having about 36 carbon atoms or that such polyesters are useful as functional blood partitioning compositions having reduced affinitity for therapeutic agents present in blood such as phenobarbital and imipramine.
U.S. Pat. No. 4,148,764 teaches polyesters useful as a barrier material in blood separation assemblies. The polyesters are comprised of the reaction products of essentially stoichiometric quantities of: (1) a dicarboxylic acid component which is comprised of: (a) aliphatic dicarboxylic acid having from 4 to about 12 carbon atoms, (b) a polymeric fatty acid containing 75% by weight or more of a C 36 dibasic acid; (2) a diol component which includes a branched-chain aliphatic dihydric alcohol having 3 to 8 carbon atoms, a mixture of these dihydric alcohols, or a mixture containing at least 50% by weight of the branched-chain aliphatic dihydric alcohols and a straight-chain aliphatic dihydric alcohol having 2 to 8 carbon atoms. The equivalents ratio of (a) to (b) ranges from 0.80:0.20 to 0.97:0.03. The polyesters have an average molecular weight of 2,000-8,000, a kinematic viscosity at 210° F. of 2,000-8,000 centistokes, and a density in the range of from 1.015 to 1.060 g/cm 3 . U.S. Pat. No. 4,148,764 does not teach that the dicarboxylic acid component contains a third dicarboxylic acid having from 13 to about 22 carbon atoms. The presence of the third dicarboxylic acid having from 13 to about 22 carbon atoms according to the invention produces a product which, when formulated together with other ingredients such as a suitable filler and compatible surfactant, is a functional blood partitioning composition which has reduced affinitity for therapeutic agents present in blood such as phenobarbital and imipramine. U.S. Pat. No. 4,480,087 teaches polyester waxes which contain as the acid member at least 75 mole percent of alkylsuccinic anhydride or alkenylsuccinic anhydride and the acid functional derivatives thereof, and linear aliphatic and cycloaliphatic glycols having from 2 to 12 carbon atoms as the diol member. The remaining acid member may be a C 4 to C 10 dibasic aliphatic acid such as succinic or adipic acid. The patent does not teach polyester compositions having less than 75 mole percent of alkylsuccinic anhydride which is an aliphatic dicarboxylic acid having from 13 to about 22 carbon atoms nor does it contain any suggestion that such polyester compositions are useful as functional blood partitioning compositions having reduced affinitity for therapeutic agents present in blood such as phenobarbital and imipramine.
SUMMARY OF THE INVENTION
In accordance with the present invention, it has been discovered that certain highly hydrophobic polyesters satisfy the above-noted criteria for incorporation in a clinically useful blood partitioning composition. The polyesters according to the invention comprise a dicarboxylic acid member and a diol member. The dicarboxylic acid member is comprised of three separate dicarboxylic acid components. The first acid component includes from about 5 to about 60 mole percent of an aliphatic dicarboxylic acid having from 13 to about 22 carbon atoms. The second contains from about 35 to about 90 mole percent of an aliphatic dicarboxylic acid having from 4 to about 12 carbon atoms. The third is comprised of from about 5 to about 25 mole percent of an aliphatic dicarboxylic acid having about 36 carbon atoms. The molar ratio of acid member to diol member is about 1:1. The polyester is in the form of a viscous liquid and having a density at room temperature in the range of 1.01-1.09.
The polyesters of the invention are readily formulated together with other ingredients, typically a suitable filler and compatible surfactant, into functional blood partitioning compositions. The density of the finished blood partitioning composition is controlled within prescribed limits, so that during centrifugation the composition becomes stably positioned at the interface between the serum or plasma phase and heavier cellular phase and, when centrifugation is terminated, forms a continuous integral barrier within the blood collection vessel to prevent the two phases from recombining or mixing, especially when decanting or pipetting the serum or plasma. The blood partitioning compositions of the invention are advantageously employed in small amounts, on the order of 1-5 gm., in a 10 ml blood collection vessel of the type previously described which are then ready for use in blood sampling and analysis in the usual way. The polyester-based blood partitioning compositions of the invention are especially suited for use in TDM procedures, displaying negligible interaction with commonly monitored therapeutic agents.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The polyesters according to the invention have molecular weights from about 3,000 to about 12,000 (number average, as determined by gel permeation chromatography). The polyesters of the invention are produced in the form of viscous liquids, having a density at room temperature in the range of 1.01-1.09. Particularly notable among the properties of these polyesters is their inertness, making them especially useful in TDM programs. The polyesters of the invention are also highly hydrophobic, exhibiting negligible water solubility. The physical and chemical properties of these polyesters are uniformly maintained over extended periods prior to use, as well as during transportation and processing of blood samples. Among the other notable characteristics of these polyesters is the ability to undergo ultracentrifugation for up to 1 hour at up to 1500G (G being the ratio of centrifugal acceleration to acceleration of gravity), without any detectable adverse effect.
The polyesters of the invention are further characterized by having an acid value of 2 or less, an hydroxyl value of 25 or less and a 210° F. kinematic viscosity of about 1700-4000 centistokes.
Polyesters having the above-described properties are especially useful as blood partitioning agents in blood collection vessels where they provide a continuous integral barrier or seal between the serum and clot portions of blood. In other words, the polyester completely partitions the separated phases so that the serum and cellular or clot portions are no longer in contact at any point, forming a unitary seal which firmly adheres to the inner surface of the blood collection vessel. By forming a continuous, integral barrier in this way, it is possible to easily remove the serum or plasma portion by decanting or pipetting, with the clot portion remaining undisturbed in the collection vessel.
The dicarboxylic acid member of the polyesters of the invention is comprised of three dicarboxylic acids, the first of which includes aliphatic dicarboxylic acids having from 13 to about 22 carbon atoms. The first dicarboxylic acid is preferably selected from the group of polyalkenylsuccinic acids such dodecenylsuccinic acid or dodecenylsuccinic anhydride, adducts of unsaturated monocarboxylic acids such as a linoleic acid-acrylic acid adduct, or a mixture thereof.
The second group of dicarboxylic acids includes saturated aliphatic acids having 4-12 carbon atoms. More preferably, these acids have from 4-9 carbon atoms and are essentially straight-chain acids. Representative short chain dicarboxylic acids include succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedoic acid and dodecanedoic acid. Mixtures of two or more of such short-chain dicarboxylic acids may be used, if desired.
The third group of dicarboxylic acids includes aliphatic dicarboxylic acids having from about 32-40 carbon atoms obtained by the polymerization of olefinically unsaturated monocarboxylic acids having from 16-20 carbon atoms, such as palmitoleic acid, oleic acid, linoleic acid, linolenic acid and the like. Polymeric fatty acids and processes for their production are well known. See, for example, U.S. Pat. Nos. 2,793,219 and 2,955,121. Polymeric fatty acids particularly useful in the practice of this invention preferably will have as their principal component C-36 dimer acid. Such C-36 dicarboxylic acids are obtained by the dimerization of two moles of a C-18 unsaturated monocarboxylic acid, such as oleic acid or linoleic acid, or mixtures thereof, e.g., tall oil fatty acids. These products typically contain 75% by weight or more of C-36 dimer acid and have an acid value in the range of 180-215, saponification value in the range of 190-215 and neutral equivalent from 265-310. The dimer acids may be hydrogenated prior to use. To increase the C-36 dimer content and reduce the amount of by-product acids, including unreacted monobasic acid, trimer and higher polymer acids, the polymeric fatty acid may be molecularly distilled or otherwise fractionated.
The first group of dicarboxylic acid comprises from about 5 to about 60 mole percent of the total acid component of the polyester. The second dicarboxylic acid group comprises from about 35 to about 90 mole percent of the total acid component of the polyester. The third group comprises from about 5 to about 25 mole percent of the total acid component of the polyester.
It will be apparent to those skilled in the art that the various art-recognized equivalents of the aforementioned dicarboxylic acids, including anhydrides and lower alkyl esters thereof, may be employed in preparing the polyesters of the invention. Accordingly, as used herein, the term "acid" is intended to encompass such acid derivatives. Methyl esters are particularly advantageous for the preparation of the polyesters described herein. Mixtures of acids, anhydrides and esters may also be reacted to obtain the desired product.
Suitable diols which may be reacted with the above described dicarboxylic acid(s) to yield the polyesters of the invention include diols of the formula: ##STR1## in which R 1 , R 2 , R 3 and R 4 are independently selected from the group consisting of hydrogen and an alkyl group having 1-4 carbon atoms, n=1-4 and x=0-4. Representative diols falling within the foregoing formula include neopentyl glycol, propylene glycol, diethylene glycol, triethylene glycol, 3-methyl-1,5- pentane diol, 1,2 propane diol, 1,3-butane diol, 1,2-butane diol, 1,2-pentane diol, 1,3-pentane diol, 1,4-pentane diol and the like. The preferred diols contain from 3-5 carbon atoms, with particularly useful polyesters products being obtained using neopentyl glycol, propylene glycol, triethylene glycol, or mixtures thereof. In a particularly preferred embodiment of the invention, in which a mixture of neopentyl glycol and propylene glycol is used, the amount of neopentyl glycol comprises about 70 to about 95 equivalent percent, and the amount of propylene glycol comprises about 5 to about 30 equivalent percent of the total diol component equivalents.
Conventional esterification procedures and equipment are used to obtain the polyester of the invention. The reactive components are normally added to the reaction vessel as a unit charge and the reaction mixture is then heated with agitation at a temperature from about 150°-250° C. for a period of time sufficient to substantially complete the esterification reaction. The reaction may be driven to completion by application of vacuum (typically 1-5 mm Hg absolute at 200°-250° C.) until the desired properties are obtained. Vacuum distillation removes the final traces of water, any excess reactants and small amounts of other volatile materials present in the reaction mixture.
If an improvement in color is desired, the polyester may be bleached by any of the well known and acceptable bleaching methods, e.g., using hydrogen peroxide or chlorite. Alternatively, the polyester may be decolorized by filtering through a filter aid, charcoal or bleaching clay.
The rate of esterification may be enhanced by the use of known esterification catalysts. Suitable esterification catalysts for enhancing the rate of esterification of free carboxyl groups include phosphoric acid, sulfuric acid, toluenesulfonic acid, methane sulfonic acid, and the like. The amount of such catalyst may vary widely, but most often will be in an amount from about 0.1% to about 0.5% by weight, based on the total reactant charge. Catalysts useful for effecting ester interchange include dibutyltin diacetate, stannous oxalate, dibutyltin oxide, tetrabutyl titanate, zinc acetate and the like. These catalysts are generally employed in an amount ranging from about 0.01% to 0.05% by weight, based on the total resistant charge. When such catalysts are used, it is not necessary that it be present throughout the entire reaction. It is sometimes advantageous in order to obtain products having good color and relatively low acid value, on the order of 2 mg KOH/gm, or less, to add the catalyst during the final stages of the reaction. Upon completion of the reaction, the catalyst may be deactivated and removed by filtering or other conventional means.
Inert diluents, such as benzene, toluene, xylene and the like may be employed for the reaction, however, the use of diluents is not necessary. It is generally considered desirable to conduct the reaction without diluents since the resultant polyester can be directly used as it is obtained from the reaction vessel. A small excess (based on the equivalents of acid present) of the diol component may be used if desired. The excess diol serves as the reaction medium and reduces the viscosity of the reaction mixture. The excess diol is distilled off as the esterification is carried to completion and may be recycled to the reactor if desired. Generally, about 20% by weight excess diol, based on the total weight of the diol component, will suffice. The more volatile glycols are commonly used for this purpose.
A particularly useful blood partitioning agent is obtained by reacting a total of 1.0 mole of acid member which comprised of: (i) about 10 mole percent of linoleic acid-acrylic acid adduct having 21 carbon atoms as the first acid component, (ii) about 75 mole percent of a mixture of dimethyl succinate, dimethyl glutarate, and dimethyl adipate as the second acid component, and (iii) about 15 mole percent of oleic dimer acid as the third acid component with about 1.0 moles of diol member comprising neopentyl glycol and propylene glycol. The relative approximate weight percentages of the esters in the ester mixture being 1% dimethyl succinate, 75% dimethyl glutarate and 24% dimethyl adipate. The equivalents ratio of neopentyl glycol to propylene glycol ranges from about 0.75:0.25 to about 0.90:0.10.
The source of the acids or acid derivatives and the manner by which the dicarboxylic acid blends are prepared, in those embodiments where such blends are used, is of no consequence so long as the resulting blend contains the specified acids or acid derivatives in the required ratios. Thus, dicarboxylic acid or acid derivative blends may be obtained by mixing the individual acid components. On the other hand, mixtures of acid obtained as by-products from various manufacturing operations and which contain one or more of the necessary acid components may be advantageously utilized. For example, mixed dimethyl esters of succinic, glutaric and adipic acids may be obtained as a co-product from the manufacture of adipic acid and may be conveniently blended with any other acid, e.g., oleic dimer acid selected for inclusion in the polyester of the invention.
Preparation of blood partitioning compositions using the polyesters of the invention may be carried out in the manner described in commonly owned U.S. Pat. Nos. 4,101,422 and 4,148,764, the entire disclosures of which are incorporated by reference in the present specification, as if set forth herein in full.
Determination of the extent of interaction between the polyesters of the invention and commonly monitored drugs may be carried out using well known recovery experiments and drug measurement techniques, such as, gas chromatography, gas-liquid chromatography, high-performance liquid chromatography, thin layer chromatography or immunoassay techniques, including radioimmunoassay, enzyme immunoassay, fluorescence polarization immunoassay, nephelometric assay, and the like. A variety of suitable procedures are reported in the literature. See, for example, Bergqvist et al., supra. Such determinations may be carried out using human serum, or commercially available bovine serum, if desired.
The following examples are presented to illustrate the invention more fully, and are not intended, nor are they to be construed, as a limitation of the scope of the invention. In the examples, all percentages are on a weight basis unless otherwise indicated.
EXAMPLE 1
A reactant charge was prepared, including 558 gm. of dodecenylsuccinic anhydride and 192 gm. of propylene glycol (which includes a 20% excess over the stoichiometric requirement for the reaction, to serve as the reaction medium), placed in a one liter reaction vessel equipped with a stirrer, fused and heated gradually to a final temperature of 225°-230° C. Water of reaction was collected from a temperature of approximately 190° C. The diol component was retained in the reaction mixture by the action of a Vigreaux fractionating column. The rate of temperature increase was regulated so that the still head temperature did not exceed 110° C. during the initial condensation. When the rate of water evolution diminished sharply, i.e., when about 85% of the expected distillate had been collected, a partial vacuum was applied to complete the conversion of acid groups present to esters (about 28 inches vacuum at 225° C.). The vacuum esterification stage required about 3-4 hours. At this point, an interchange catalyst was introduced (0.02% dibutyltin diacetate (DBTDA) based on the total reactant charge), the fractionating column was removed, and relatively high vacuum applied (approximately 1-2 mm Hg). Distillation of volatile diol proceeded slowly until the target viscosity was achieved, which required approximately 6 hours. The product was filtered through a coarse screen. The polyester recovered had an acid value of 3.0, an hydroxyl value of 22.4, 210° F. kinematic viscosity of 1978.
EXAMPLE 2
The same general procedure described in Example 1 was followed in preparing a polyester from a reactant charge comprising 314 gm. of dodecenylsuccinic anhydride, 221 gm. of azelaic acid and 215 gm. of propylene glycol, except that one half the amount of the DBTDA catalyst was used and vacuum distillation proceeded for an additional 2 hours. The resultant product had an acid value of 1.8, a hydroxyl value of 9.5, 210° F. kinematic viscosity of 2554.
EXAMPLE 3
A polyester was prepared from a reactant charge comprising 335 gm. linoleic acid-acrylic acid adduct, 661 gm. azelaic acid, 405 gm. neopentyl glycol and 99 gm. propylene glycol. The reaction was carried out in a 2 liter reaction vessel equipped with a stirrer and a Vigreaux fractionating column, following the same general reaction conditions set forth in Example 1, above, except that vacuum distillation was performed for approximately 10 hrs. overall. The polyester obtained from this reaction had an acid value of 0.73, an hydroxyl value of 18.6, 210° F. kinematic viscosity of 1912 and density at room temperature of 1.0348.
EXAMPLE 4
A polyester was prepared from a reactant charge including 229 gm. linoleic acid-acrylic acid adduct, 393 gm. of a mixture of dicarboxylic acid dimethyl esters, including 75% dimethyl glutarate, 24% dimethyl adipate and 1% dimethyl succinate, 390 gm. oleic dimer acid, 352 gm. neopentyl glycol and 86 gm. propylene glycol. The reaction was run in a 2 liter reaction vessel equipped as described in Example 3. The reaction conditions described in Example 1 were followed for the most part with certain variations. Specifically, the catalyst (DBTDA) was introduced at the outset of the reaction, and in an amount of 0.02%, based on the total weight of the reactant charge. In addition, the heating rate was adjusted so that the head temperature did not exceed 90° C. until an amount of distillate corresponding approximately to the predicted weight of methanol was collected. The upper limit of the reaction temperature was approximately 225° C. Stripping of the reaction medium to the desired viscosity was carried out essentially as described in Example 1, above. The polyester obtained from the reaction had an acid value of 1.1, an hydroxyl value of 14.1, 210° F. kinematic viscosity of 1972 and density at room temperature of 1.0202.
EXAMPLE 5
A reactant charge was prepared including 508 gm. dodecenylsuccinic anhydride 1116 gm. oleic acid dimer, 1123 gm. of the ester mixture described in Example 4, 1008 gm. neopentyl glycol and 245 gm. propylene glycol. This charge, together with 0.02% of DBTDA, was placed in a 5 liter reaction vessel equipped as described in Example 3, and reacted following the general procedure of Example 4. The reaction yielded a polyester having an acid value of 0.3, an hydroxyl value of 14.1, 210° F. kinematic viscosity of 2510 and density at room temperature of 1.0226.
EXAMPLE 6
A polyester was prepared from a reactant charge, including 196 gm. linoleic acid-acrylic acid adduct, 193 gm. dimethyl azelate, 558 gm. of the ester mixture described in Example 4, 445 gm. neopentyl glycol and 108 gm. propylene glycol, together with 0.02% DBTDA, following the general procedure of Example 4, with the exception that the usual vacuum esterification stage to reduce free acidity proved unnecessary in this case. The product of the reaction had an acid value of 0.4, an hydroxyl value of 8.3, 210° F. kinematic viscosity of 2256 and density at room temperature of 1.082.
EXAMPLE 7
To a 2 liter vessel was charged 735 grams of Emerox™ 1110 azelaic acid, 259 grams of Empol™ 1016 dimer acid, 101 grams of 1,2-propylene glycol, and 405 grams of neopentyl glycol. The reaction was carried out in the same manner as described in Example 1 including the addition of 0.02% di-n-butyltin diacetate when the evolution of water was complete. The resulting polyester exhibited an acid value of 1.1, a hydroxyl value of 14.8, a kinematic viscosity of 3370 cst @210° F., and a density of 1.0232@25° C.
EXAMPLE 8
To a 2 liter vessel was charged 585 grams of Emerox™ 1110 azelaic acid, 238 grams of Empol™ 1016 dimer acid, 174 grams of dodecenylsuccinic anhydride, 96 grams of 1,2-propylene glycol, and 394 grams of neopentyl glycol. The reaction was carried out in the same manner as described in Example 1 including the addition of 0.02% di-n-butyltin diacetate when the evolution of water was complete. The resulting polyester exhibited an acid value of 0.80, a hydroxyl value of 24.5, a kinematic viscosity of 2132 cst @210° F., and a density of 1.0196@25° C.
Polyesters prepared as described in the foregoing examples were evaluated for interaction with the antidepressant, imipramine (IM) and the anticonvulsant, phenobarbital (PB), two drugs which are commonly administered under TDM. A recovery of 90% was established as a benchmark for utilization of the polyesters of the invention in TDM programs. The results of these evaluations are set forth below in Table I. The entries under the headings IM and PB are the percent recoveries of imipramine and phenobarbital respectively.
TABLE I______________________________________C.sub.4-12 C.sub.13-22 C.sub.36 DIOL IM PB______________________________________Ex 1 -- 1.0 -- 1.0 93 97Ex 2 0.5 0.5 -- 1.0 89 96Ex 3 0.812 0.188 -- 1.0 88 95Ex 4 0.90 0.10 -- 1.0 97 99Ex 5 0.64 0.18 0.18 1.0 86 100Ex 6 0.90 0.10 -- 1.0 89 92Ex 7.sup.1 0.884 -- 0.116 1.0 77 95Ex 8 0.748 0.098 0.154 1.0 87 97______________________________________
1-a polyester according to U.S. Pat. No. 4,148,764 All of the recovery values reported above were obtained using commercially available bovine serum. Experience has shown that higher recovery values (up to about 2% higher) are obtainable with human serum.
The data in Table I show that a substantial improvement in the ability to determine the level of imipramine in bovine sera by recovery of radioactive content, expressed as a percentage of the dose introduced, was achieved when at least half of the C 36 dimer acid content of the polyesters taught in U.S. Pat. No. 4,184,764 was replaced by acid, ester, or anhydride having from 13 to 22 carbon atoms with a relatively large pendant alkyl group having from about 9 to about 13 carbon atoms.
While the present invention has been described and exemplified above in terms of certain preferred embodiments, various other embodiments may be apparent to those skilled in the art. Accordingly, the invention is not limited to the embodiments specifically described and exemplified, but variations and modifications may be made therein and thereto without departing from the spirit of the invention, the full scope of which is delineated by the following claims.
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A polyester is provided which facilitates the separation of blood into light and heavy phases via centrifugation in a blood collection vessel. The polyester is useful as a component of a partitioning composition formulated to have appropriate specific gravity to be positioned intermediate the light and heavy blood phases during centrifugation. A partitioning composition including a polyester of the invention provides a particular advantage in blood collection vessels used in therapeutic drug monitoring, due to the relatively low affinity between the polyester component of the composition and commonly monitored classes of drugs.
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CROSS-REFERENCE TO RELATED APPLICATION
This application claims the benefit of U.S. Provisional Application No. 60/275,565, filed Mar. 14, 2001.
FIELD OF THE INVENTION
This invention is directed to improving the adhesion of nylon coatings on substrates of nylon and polyester. More specifically this invention is directed to the use of select formaldehyde resins with high imino content or partially alkylated or non-alkylated derivatives thereof to improve the adhesion of mixed nylon polymers to filaments, films, parts and the like made from nylons and polyesters.
BACKGROUND OF THE INVENTION
Nylon “multi-polymers” are nylons made from a mixture of nylon forming monomers such that the nylon polymer contains a mixture of at least two types of nylon structural units. These types of nylons are sold commercially for a variety of coatings and adhesive applications. Generally these nylons are readily soluble in organic solvents and are generally applied as solutions. See for example brochures entitled “Elvamide® Nylon Multipolymer Resins, Properties and Uses” (September 1977) and “Elvamide® Nylon Multipolymer Resins for Thread Bonding” (October 1977), both published by E.I. DuPont de Nemours and Company, Inc.
Typically, sewing threads are coated with polymeric materials (and with lubricants added in most cases) to protect them from abrasion during the sewing operation. Furthermore, with twisted multi-filament sewing threads the polymeric coatings (also referred to as thread bonding) also prevent fraying and unraveling (untwisting) of the individual filaments. See generally, the December 1990 DuPont brochure and Kohan, M. I., “Nylon Plastics Handbook” Hansen/Gardner Publications, Inc. (1995) pages 283-290.
Nylon multi-polymers have been used for thread bonding applications for several decades. However, there is increasing demand for improved adhesion of the coating to the thread, as for example in highly demanding modern applications. This is also of paramount importance for applications relying upon tightly woven fabric, for example in luggage and automotive air bags, leather, and the like. In such applications abrasion of the thread is high and the operating needle temperature is much higher compared to more loosely woven fabric applications such as those used in apparel. The poor adhesion of coatings results in a ‘snake skin” effect where the coating comes off the surface of the thread. This results in loose coating material that jams the needle requiring stoppage of the operation. Further, poor aesthetics are associated with loose coating material as can be seen on inspection of the surface of the thread.
In the case of sewing threads and fabrics, nylon copolymers, terpolymers, and higher multi-polymers are used for coatings applications. These polymers are usually soluble in organic solvents, especially alcohols. The nylon coating is typically applied by dipping the thread in a solution of the nylon multi-polymer and then subsequently passing the thread through a drying chamber and then to a fusing chamber generally at a temperature above the melting point of the nylon mixed polymer. Melting of the nylon multi-polymer coating on the thread promotes adhesion. Nylon mixed polymers are generally favored for this use because of their toughness, good abrasion resistance, and ready solubility in solvents. For more information on these procedures and the benefits associated with nylon mixed polymers, see the Elvamide® (October 1977) brochure and the “Nylon Plastics Handbook” mentioned above.
The brochures mentioned above describe the ability of thermosetting resins such as epoxy, phenol-formaldehyde, and melamine-formaldehyde to cross-link nylon multi-polymers and improve the adhesion of the coating. The nylon multi-polymer reacts with these thermosetting resins to form thermoset-thermoplastic compositions.
U.S. Pat. No. 4,992,515 describes the use of Cymel® 1135 available from Cytek Industries, Inc., a fully alkylated melamine-formaldehyde resin, and strong acid catalyst to cross-link nylon 6/66/69, nylon 6/66/610, and nylon 6/66/612 terpolymers. The extent of cross-linking achieved was measured by the insolubility in the original solvent of the coating material after cross-linking. The cross-linked nylon coating becomes insoluble in the solvent. However, no data was provided as to how much improvement in adhesion and resistance to unraveling were achieved.
Various types and re-activities of formaldehyde derived cross-linking agents are disclosed in a brochure entitled “High Solids Amino Crosslinking Agents” (September 1994) available from Cytec. For example, Cymel® 325 used in several examples described below has free formaldehyde of 1.0 weight percent. Other grades of Cymel® can contain up to 3.5 weight percent free formaldehyde and are useful in the practice of the instant invention. These and other cross-linking agents are prepared by the reaction of amine functionalities with formaldehyde resulting in the replacement of the hydrogen on the amine functionality by a hydroxymethyl group. The hydroxymethy function is reacted with an alcohol to convert the hydroxy function to an alkoxy. Many classes of these crosslinking agents are possible depending on the extent of reaction. For example, there are commercially available types in melamine-formaldehyde cross-linking resins. Partial reaction of the amino functionalities in melamine (Structure 1 below)
results in Structure 2
where only some of the hydrogens have been replaced by the hydroxymethyl groups. Alkylation reaction of Structure 2 with an alcohol results in the conversion of the hydroxy group to alkoxy group as shown in Structure 3.
Melamine-formaldehyde resins containing the type of functionality as in Structure 3 are classified as high imino-type resins. Complete replacement reaction of melamine with formaldehyde and subsequent partial alkylation results in Structure 4.
Again resins containing this type of functionality are classified as partially alkylated. If the reaction with alcohol is allowed to reach completion the fully alkylated derivative (Structure 5)
is obtained. Those having skill in the art will readily appreciate that different classes of functionalities (eg, amino or alkoxy groups) may be designed into the molecule. Each class is chemically distinct and has different characteristics and re-activities. The fully alkylated resins such as Cymel® 1135 require catalysis by strong acids to initiate their reaction.
There is a longstanding need for a technique to improve the overall adhesion of nylon coatings to substrates of nylon and polyester. Improvements in such adhesion will promote better aesthetic qualities to the article formed, and also provide an economic benefit in that less material is rejected as nonconforming for the intended final product.
An object of the instant invention is to develop a processing technique and coating solutions to improve the adhesion of nylon coatings to nylons, polyesters, and mixtures thereof. This development applies not only to threads but in general to any substrates where such adhesion is desirable. A further object of the instant invention is to provide such techniques and solutions that are readily adaptable and useful for a variety of applications including monofilaments, multifilaments, films, tubings, shaped parts and the like. A feature of the present invention is the durability of the adhesive bond itself making it suitable for rigorous applications in which the material is extensively handled and manipulated. An advantage of the present invention is that the procedure may utilize any of a variety of solvents. These and other objects, features and advantages of the invention will become better understood upon having reference to the following descriptions of the invention.
SUMMARY OF THE INVENTION
Coating solutions to promote the adhesion of polyamides to substrates of polyamides, polyesters or mixtures thereof are disclosed herein. These solutions comprise:
(a) polyamide having a solubility of at least 0.5 weight percent in select organic solvents, and
(b) 1 to 100 weight percent based on the weight of the polyamide of high imino, partially alkylated or non-alkylated formaldehyde resins selected from the group consisting of melamine-formaldehyde, glycoluril-formaldehyde, benzoguanamine-formaldehyde, and mixtures thereof.
Optionally, 0-20 weight percent based on the weight of the formaldehyde resin of a catalyst may be added. Additionally, fully alkylated melamine-formaldehyde, glycoluril-formaldehyde, or benzoguanamine-formaldehyde resins may be added. The resins (b) function as adhesion promoters. The resins (b) are preferably incorporated in the range of 1-40 weight percent (most preferably 1-20 weight percent) based on the weight of the polyamide.
There are also disclosed herein processes for the coating of these substrates with the coating solutions of the invention. Such processes are readily appreciated by those having skill in the art. See for example the thread coating procedures described herein.
DETAILED DESCRIPTION OF THE INVENTION
Nylons suitable as coating materials for purposes of the instant invention are polyamides derived from a lactam containing 6-12 carbon atoms, polyamides derived from 2-12 carbon diamines and 6-12 carbon diacids, polyamides derived from polypropylene glycol diamine or polyethylene glycol diamine and 6-12 carbon atom diacids and mixed polymers of the aforementioned polyamides with the proviso that these polyamides must have a solubility of at least 0.5 weight percent in alcohols, phenols, cresols, or mixtures of these solvents. Preferably the polyamide suitable as coating material is a multi-polymer such as 6/66 copolymer or 6/66/X where X is a polyamide derived from lactam containing 7-12 carbon atoms or polyamide derived from 2-12 carbon diamines and 6-12 carbon diacids.
Suitable solvents of the instant invention are methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, furfuryl alcohol, benzyl alcohol, phenols, and m-cresols or combinations of these solvents. The selected solvent or combination of solvents may also contain water. Additionally, chlorinated solvents may be added as diluent. The selection of suitable solvent will also depend on several factors as is appreciated by those of skill in the art, such as geometry of the substrate, thickness of the article, and the like.
Examples of polyamides suitable as substrates herein for mono-filaments, multi-filaments, films, or tubings are those derived from 4-12 carbon diamines and 6-12 carbon diacids, lactams with 6-12 carbon atoms and mixed polymers of the aforementioned monomers. Examples of polyesters suitable for mono-filaments, multi-filaments, films, or tubings are polyethylene terephthalate, polypropylene terephthalate, or polybutyleneterephthalate, and their copolymers. It is recognized by those familiar with the art that adhesion and compatibility between polymers are favorable when the two polymers are of the same class or type ie polar polymers will tend to have better adhesion with other polar polymers. Thus, nylon is inherently more adherent to other nylons than to polyesters.
The melamine-formaldehyde resins suitable for these inventions are those that contain imino and hydroxymethyl moieties such as Cymel® 325, 1158, 385, 1172 and 1123. These are commercial grades of materials available from Cytek Industries, Inc. The melamine-formaldehyde resins, with or without the catalyst, preferably is added to the nylon multi-polymer solution and applied to the substrate as a single solution. However, with comparable effectiveness, the melamine-formaldehyde resins, with or without the catalyst, can be pre-coated to the substrate.
Suitable catalysts are inorganic acids such as phosphoric acid, organic acids such as p-toluenesulfonic acid, acetic acid, oxalic acid, and phthalic acid.
Materials other than threads such as mono-filaments, tubings, fabrics, films and other extruded or molded parts, in many cases, also could be coated with nylon polymer to enhance surface properties. These properties include for example abrasion resistance, barrier properties or the modification of the surface of a polymer such as polyester to make the surface more polar for a subsequent operations where the modified surface may be more amenable.
Articles to which the instant coating solutions have been applied are also disclosed and claimed herein. A coated article comprising a substrate of polyamides, polyesters, or mixtures thereof is first provided. Then a coating solution is applied thereto to form a precoated substrate. The coating solution comprises at least 0.5 weight percent of high imino, partially alkylated, or non-alkylated formaldehyde resins selected from the group consisting of melamine-formaldehyde, glycoluril-formaldehyde, benzoguanamine-formaldehyde and mixtures thereof. Finally a polyamide with a solubility of at least 0.5 weight percent in select organic solvents is applied to the precoated substrate.
The invention will become better understood and appreciated upon having reference to the following examples.
EXAMPLES
Thread Coating Procedure
The thread coating was conducted in a laboratory coating unit similar to the one described in the DuPont brochure relating to Elvamide® (October 1977) and the “Nylon Plastics Handbook”, both referenced earlier. The drying and fusing sections are heated with hot nitrogen passed through electrical tube heaters provided with controllers to allow independent temperature control of the two sections. In a typical coating experiment the thread is passed between cheesecloth saturated with the coating solution by continuously dripping the coating solution onto the cloth from a dropping funnel. The residence time of the thread in the drying section is six seconds and also six seconds in the fusing section. The residence time is controlled by the take up speed of the spool motor. To provide a basis for accurate comparisons, the specified threads were always selected from the same spool.
Abrasion Resistance & Interply Adhesion
After coating the thread is conditioned in a 50% Relative Humidity (RH) chamber for six days before testing. One end of the thread is attached to a reciprocating arm driven by an electric motor (at a rate of 44 cycles/minute) and the other end to a 230.0 g weight (such that the thread abraids against the nylon 66 mono-filament). The thread hangs over a nylon 66 mono-filament with a diameter of 0.025-inch to 0.030-inch. There is provided a counter that records the number of cycles. During the test, the appearance of the thread is observed visually through a 50× magnifying lens. The point where the coating has abraded is observed as the number of cycles. Increased number of cycles reflects increased abrasion resistance.
The interply adhesion of the samples is compared qualitatively by twisting the coated thread opposite the original twist direction. A qualitative grading system from 0 to 3 was used. Zero is when the plies completely separate from each other; 1 is when the plies separate but some portion of the plies are still attached to each other; 2 is when only a small portion of the plies separate from each other; and 3 is when there is no visible separation of the plies. In close cases, gradations in units of 0.5 were used (for example, “1.5” and “2.5”).
Examples 1 & 2
An 11.0 percent by weight solution of Elvamide® 8061 was made by heating Elvamide® 8061 and methanol in a flask fitted with a magnetic stirrer and a condenser. The amount of solution required depends on the amount of thread to be coated. In a typical experiment a 100-gram solution is made by heating 11.0 grams of Elvamide® 8061 and 89.0 grams of methanol.
A 210-denier, 3-ply nylon thread was coated as described above using 6 seconds residence time in the drying section and 6 seconds in the fusing section. Results are shown in the table below.
DRY-
ING
WT. %
CYCLES
EXAM-
TEMP.,
FUSION
COAT-
TO
INTERPLY
PLE
C.
TEMP. C.
ING
ABRASION
ADHESION
Comp. 1
80
120
4.5
24
3
Comp. 2
120
170
4.7
53
3
Examples 3 & 4
A methanol solution containing 11.0 weight percent Elvamide® 8061, 2.0 weight percent Cymel® 1135 and 0.2 weight percent p-toluenesulfonic acid was prepared as in Example 1. This solution was used to coat a 210-denier, 3-ply nylon thread as in Example 1. This example is in accordance with U.S. Pat. No. 4,992,515 using a fully alkylated melamine-formaldehyde cross-linking agent and a strong acid catalyst.
WT. % p-
TOLUENE-
SULFONIC
DRYING
FUSION
WT. %
CYCLES TO
INTERPLY
EXAMPLE
WT. % CYMEL ®
ACID
TEMP., C.
TEMP. C.
COATING
ABRASION
ADHESION
Comp. 3
2% Cymel(R)
0.2
80
120
3.7
32
2
1135
Comp. 4
2% Cymel(R)
0.2
120
170
4.1
>200
1
1135
The results show that at the lower fusion temperature (Example 3) the abrasion resistance is not significantly different than Elvamide® 8061 by itself (Example 1). The abrasion resistance at the higher fusion temperature (Example 4) was significantly improved but the interply adhesion was very poor.
Examples 5 to 16
Solutions for coating were prepared as in the previous examples using a ration of 11.0 weight percent Elvamide® 8061 in combination with various Cymel® cross-linking agents. These solutions were used to coat 210-denier, 3-ply nylon thread as in Example 1.
WT. % p-
TOLUENE-
SULFONIC
DRYING
FUSION
WT. %
CYCLES TO
INTERPLY
EXAMPLE
WT. % CYMEL ®
ACID
TEMP., C.
TEMP. C.
COATING
ABRASION
ADHESION
Comp. 5
2% Cymel(R) 303
0.2
80
120
3.4
53
2.5
Comp. 6
2% Cymel(R) 303
0.2
120
170
4.4
>200
0.5
7
2% Cymel(R) 325
0.2
80
120
4.1
20
3
8
2% Cymel(R) 325
0.2
120
170
5.6
>200
2
9
2% Cymel(R) 325
0
80
120
2.9
148
3
10
2% Cymel(R) 325
0
120
170
4.9
75
3
11
2% Cymel(R) 385
0.2
80
120
3.4
28
3
12
2% Cymel(R) 385
0.2
120
170
4.4
>200
1.5
13
2% Cymel(R) 385
0
80
120
4.4
42
3
14
2% Cymel(R) 385
0
120
170
4.7
45
3
15
2% of 1/1 Cymel(R)
0
80
120
4
74
3
303/325
16
2% of 1/1 Cymel(R)
0
120
170
1.2
150
3
303/325
Comparative Examples 5 and 6 illustrate the use of another fully alkylated melamine-formaldehyde resin in accordance with U.S. Pat. No. 4,992,515. At the lower fusion temperature (Comp. Example 5) the abrasion resistance was slightly better than with Elvamide® 8061 alone (Comp. Example 1) and with good interply adhesion. However, at the higher fusion temperature although the abrasion resistance was improved, the interply adhesion was poor (Comp. Example 6). On the other hand, the use of both Cymel® 325 a high imino cross-linking agent (Examples 7 to 10) and 385 a partially alkylated cross-linking agent (Examples 11 to 14) and mixtures with fully alkylated Cymel® 303 (Examples 15 and 16) afforded both good abrasion resistance and interply adhesion.
Examples 17 to 36
Solutions for coating were prepared as in the previous examples using a concentration of 11.0 weight percent Elvamide® 8061 in combination with various Cymel® cross-linking agents. These solutions were then used to coat 220-denier, 3-ply polyethyleneterephthalate thread as in Comp. Example 1.
WT. %
WT. %
DRYING
FUSION
WT. %
CYCLES TO
INTERPLY
EXAMPLE
CYMEL ®
CATALYST
TEMP., C
TEMP. C
COATING
ABRASION
ADHESION
Comp. 17
0
0
80
120
3.2
14
2
Comp. 18
0
0
120
170
0.6
14
2
Comp. 19
1.1%
0.11%
80
120
3.2
23
2
Cymel(R) 1135
PTSA
Comp. 20
1.1%
0.11%
120
170
1.9
9
2
Cymel(R) 1135
PTSA
Comp. 21
1.1%
0.11%
80
120
1.9
25
1.5
Cymel(R) 303
PTSA
Comp. 22
1.1%
0.11%
120
170
2.9
8
2
Cymel(R) 303
PTSA
23
1.1%
0.11%
80
120
2.8
40
2
Cymel(R) 325
PTSA
24
1.1%
0.11%
120
170
0.4
14
2.5
Cymel(R) 325
PTSA
25
1.1%
0.11% Ac
80
120
4.6
55
2
Cymel(R) 325
ACID
26
1.1%
0.11% Ac
120
170
2.5
46
2
Cymel(R) 325
ACID
27
0.5%
0
80
120
4.6
37
2.5
Cymel(R) 325
28
0.5%
0
120
170
0.2
48
2.5
Cymel(R) 325
29
1.0%
0
80
120
2.2
47
2.5
Cymel(R) 325
30
1.0%
0
120
170
0.9
57
2
Cymel(R) 325
31
4.0%
0
80
120
6.4
>200
2
Cymel(R) 325
32
4.0%
0
120
170
2.9
109
2.5
Cymel(R) 325
33
2.2%
0
80
120
5
44
2.5
Cymel(R) 1158
34
2.2%
0
120
170
2.23
44
2.5
Cymel(R) 1158
35
2.2%
0.022%
80
120
4.6
66
2.5
Cymel(R) 1158
PTSA
36
2.2%
0.022%
120
170
1.9
39
2
Cymel(R) 1158
PTSA
PTSA = p-Toluenesulfonic acid
Ac ACID = Acetic acid
Comp. Examples 17 and 18 using Elvamide® 8061 alone showed abrasion resistance of only 14 which is much lower than those obtained with nylon thread Comp. Examples 1 and 2. This difference in abrasion resistance exemplifies the inherently low adhesion between dissimilar polymers such as nylon and polyester. The interply adhesion is still fairly good. The use of a fully alkylated melamine-formaldehyde cross-linking agent such as Cymel® 1135 or 303 and p-toluene sulfonic acid catalyst as described in U.S. Pat. No. 4,992,515 did not result in significant improvement in abrasion resistance (Comp. Examples 19 to 22). On the other hand, the use of high imino melamine-formaldehyde cross-linking agents such as Cymel® 325 and 1158 resulted in significant improvement in both abrasion resistance and interply adhesion.
Examples 37 to 40
A 220-denier, 3-ply polyethyleneterephthalate thread was pre-coated with a 6.0 weight percent Cymel® 350 and 1.0 weight percent p-toluenesulfonic acid catalyst in methanol using 6 seconds residence time at 80 C in the drying section and 6 seconds at 170 C in the fusion section. The pre-coated thread is then coated as in Example 1 with an 11.0 weight percent solution of Elvamide® 8061 in methanol without additional catalyst (Examples 37 & 38) and with an 11.0 weight percent Elvamide® 8061 and 1.0 weight percent p-toluenesulfonic acid solution in methanol (Examples 39 & 40).
WT. % p-
TOLUENE-
DRYING
FUSION
WT. %
CYCLES TO
INTERPLY
EXAMPLE
SULFONIC ACID
TEMP., C
TEMP., C
COATING
ABRASION
ADHESION
37
0
80
120
5.5
41
2.5
38
0
120
170
4.3
Over 80
2.5
39
1.0
80
120
6.9
54
2
40
1.0
120
170
3.4
Over 100
2.5
The results show that pre-coating the polyester thread with the Cymel® 350, a fully alkylated resin, afforded very good abrasion resistance and interply adhesion in contrast to Comparative Examples 19 to 22. The presence of catalyst in the subsequent coating with the Elvamide® 8061 was found not to have significant adverse or beneficial effects.
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Novel coating solutions are disclosed that promote desirable adhesion to substrates formed from nylon, polyester, or a combination thereof. These coating solutions include nylons having specific solubility together with select formaldehyde resins and resin mixtures. The solutions provide superior adhesion and are therefore attractive to thread applications as well as formed structures.
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CROSS-REFERENCE TO RELATED APPLICATIONS
This is a divisional application of U.S. patent application Ser. No. 09/200,014, filed Nov. 25, 1998 now U.S. Pat. 6,417,748 which is expressly incorporated herein by reference. The invention relates to a filling level measuring device operating with microwaves, having a metallic housing portion through which microwaves are transmitted and/or received and in which an insert composed of a dielectric is arranged. Furthermore, the invention relates to a process for producing the dielectric.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not Applicable.
INCORPORATION-BY-REFERENCE OF MATERIAL SUBMITTED ON A COMPACT DISC
Not Applicable.
BACKGROUND OF THE INVENTION
In filling level measurement, microwaves are sent by means of an antenna to the surface of a filled substance and the echo waves reflected at the surface are received. An echo function representing the echo amplitudes as a function of the distance is formed and used to determine the probable useful echo and its delay time. The delay time is used to determine the distance between the surface of the filled substance and the antenna.
All known methods which make it possible to measure relatively short distances by means of reflected microwaves can be used. The most well-known examples are pulsed radar and frequency-modulation continuous-wave radar (FMCW radar).
In the case of pulsed radar, short microwave transmission pulses referred to in the following as wave packets, are transmitted periodically, reflected by the surface of the filled substance and received again after a distance-dependent delay time. The received signal amplitude as a function of time represents the echo function. Each value of this echo function corresponds to the amplitude of an echo reflected at a particular distance from the antenna.
In the case of the FMCW method, a continuous microwave which is periodically frequency-modulated linearly, for example on the basis of a sawtooth function, is transmitted. The frequency of the received echo signal therefore has with respect to the instantaneous frequency which the transmitted signal has at the instant of reception a frequency difference which depends on the delay time of the echo signal. The frequency difference between transmitted signal and received signal, which can be obtained by mixing the two signals and evaluation of the Fourier spectrum of the mixed signal, consequently corresponds to the distance of the reflecting surface from the antenna. Furthermore, the amplitudes of the spectral lines of the frequency spectrum obtained by Fourier transformation correspond to the echo amplitudes. Therefore, in this case, this Fourier spectrum represents the echo function.
Filling level measuring devices operating with microwaves are used in very many branches of industry, for example in chemistry or in the food industry. Typically, the filling level in a container is to be measured. These containers generally have an opening, at which a connection piece or a flange is provided for the fastening of measuring devices.
In industrial measuring technology, dielectric rod antennas and horn antennas are regularly used for transmitting and/or receiving. Typically, a pot-like housing which has the geometry of a short-circuited waveguide is used. An exciter pin, via which microwaves are transmitted and/or received through the housing, is inserted into said housing. In the case of a horn antenna, the housing is adjoined by a funnel-shaped portion which opens out in the direction facing the container and forms the horn. In the case of the rod antenna, a rod composed of a dielectric and pointing into the container is provided. The interior space of the housing is usually filled virtually completely by an insert composed of a dielectric. In the case of the horn antenna, the insert has a conical end, pointing into the container. In the case of rod antennas, the insert is adjoined by the rod-shaped antenna.
On account of the dimensioning of the waveguide and the dielectric constant of the insert, only certain modes can be propagated. For filling level measurements, modes having a radiation characteristic with a pronounced forward lobe are preferred, in the case of circular waveguides, for example, the transverse electric (TE-11) mode. The transmission frequency is also prescribed in most countries.
In order that the dimensions of the housing are nevertheless variable within certain limits, for example to perform adaptations to dimensions of containers, a dielectric with a substantially continuously adjustable dielectric constant is advantageous. In the following text, dielectric constant always refers to the dielectric constant which is based on the vacuum dielectric constant and the value of which is equal to the quotient of the dielectric constant divided by the vacuum dielectric constant.
In DE-A 44 05 855 there is described a filling level measuring device operating with microwaves
having a metallic housing portion,
through which microwaves are transmitted and/or received and
in which an insert composed of a dielectric is arranged.
It has a rod antenna and the insert and rod antenna are composed of a dielectric. It is specified to use plastic, glass or ceramic or a mixture of said materials for this purpose.
Insert can come into contact with a medium located in the container. Depending on the application, this may well be an aggressive medium. Consequently, the insert should have in addition to the mechanical resistance required for industrial applications also a high chemical resistance.
In the case of commercially available filling level measuring devices operating with microwaves, polytetrafluoroethylene (PTFE), which has a high chemical resistance, is often used for this reason. The dielectric constant of polytetrafluoroethylene (PTFE) is not variable, however.
In U.S. Pat. No. 5,227,749 microwave circuits and components are described, for example microwave striplines, in which desired electrical and mechanical properties are achieved simultaneously by using an enclosure filled with a dielectric. The enclosure offers adequate mechanical stability, so that the dielectric can be selected purely on the basis of its dielectric properties.
Although such a construction represents a feasible approach in the case of microwave striplines and microwave circuits, it is unsuitable however for use in an antenna. The housing and insert act as a waveguide in which the microwaves form. An enclosure would have different dielectric properties than the dielectric embedded in it and, owing to its nonisotropic electrical properties, would consequently lead to considerable disturbances in the desired modes during transmitting and/or receiving.
In U.S. Pat. No. 4,335,180 there is described a dielectric for microwave circuit boards and a method of making it.
The dielectric consists of polytetrafluoroethylene (PTFE), a filler material and a fibrous material. The proportion of filler material is specified as 10 to 75 percent by weight. Among the materials specified as the filler material is aluminum oxide. The proportion of fibers is between 2.5 and 7 percent by weight of the dielectric and ensures its mechanical stability. The dielectric constant of the material is specified as 10 to 11.
This dielectric is made by blending the filler material and fibrous material into a polymer dispersion. A flocculant is added to the slurry thus formed until a dough-like material is produced, which is then shaped and dried.
In a circuit board, the fibers can be aligned in a plane by appropriate processing, for example pressing or rolling, so that a substantially homogeneous thin sheet, that is a substantially two-dimensional formation, is produced. A three-dimensional body cannot be readily produced in this way, however. In a three-dimensional body, fibers cannot be aligned in one plane by pressing or rolling. Raised fibers behave like small quills and the body remains correspondingly porous and inhomogeneous in spite of pressing. It would consequently have less mechanical strength and inhomogeneties would lead to reflections of the microwaves. There is also the risk of the porous material being saturated with moisture. Moisture in the material leads to a high loss factor tan δ.
BRIEF SUMMARY OF THE INVENTION
It is an object of the invention to specify a filling level measuring device operating with microwaves, having a housing and an insert composed of a dielectric, and a process for producing the dielectric, in which the dielectric constant of the insert is adjustable and in which the insert has a high chemical resistance and a mechanical strength adequate for industrial applications.
For this purpose, the invention comprises a filling level measuring device operating with microwaves
having a metallic housing portion,
through which microwaves are transmitted and/or received and
in which there is arranged an insert composed of a dielectric, which consists of a composite material composed of a fluoroplastic, in particular polytetrafluoroethylene (PTFE), and ceramic.
According to an advantageous refinement, the composite material has a proportion of ceramic which is below the percolation limit.
According to a further refinement, the composite material has a dielectric constant ε and the quotient of the dielectric constant ε and the vacuum dielectric constant ε 0 has a value between 2 and 10. Furthermore, the composite material preferably has a loss factor tan δ which is less than one fiftieth.
According to an advantageous development, the insert has in a portion of the housing arranged in the direction of transmission a lower proportion of ceramic than in a portion facing away from the direction of transmission.
Furthermore, the invention includes a process for producing a composite material from fluoroplastic, in particular polytetrafluoroethylene (PTFE), and ceramic, which comprises the following steps:
a) producing a mixture of powdered ceramic and powdered fluoroplastic,
b) drying the mixture,
c) pressing the mixture and
d) sintering the pressed mixture.
According to an advantageous refinement of the process, the proportion of ceramic in the mixture is below the percolation limit.
According to a further refinement of the process, the quotient of the dielectric constant ε of the composite material and the vacuum dielectric constant ε 0 has a value between 2 and 10 and the composite material has a loss factor of tan δ which is less than one fiftieth.
According to a further refinement of the process, two or more mixtures with different proportions of ceramic are produced, and the mixtures are layered one on top of the other before pressing in such a way that the proportion of ceramic in the composite material decreases from layer to layer.
The invention and further advantages are now explained in more detail with reference to the figures of the drawing, in which two exemplary embodiments of a filling level measuring device operating with microwaves are represented; identical parts are provided in the figures with identical reference numbers.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
FIG. 1 shows a longitudinal section through a first exemplary embodiment of a filling level measuring device operating with microwaves; and
FIG. 2 shows a longitudinal section through a second exemplary embodiment of a filling level measuring device operating with microwaves.
DETAILED DESCRIPTION OF THE INVENTION
In FIGS. 1 and 2 , a longitudinal section through a filling level measuring device 1 operating with microwaves and to be fastened on a container is diagrammatically represented in each case. In the container, not represented in the figures, there is a medium and the filling level measuring device 1 serves the purpose of determining the filling level of this medium in the container. To this end, in the case of the exemplary embodiment of FIG. 1 , microwaves are transmitted into the container via a rod-shaped antenna 2 a , pointing into the container, and the echo waves reflected at the surface of the filled substance are received.
In the case of the exemplary embodiment represented in FIG. 2, a horn antenna is provided. The latter has a funnel-shaped horn 2 b made of a metal, in particular a high-grade steel, which opens out in the direction facing the container.
In both exemplary embodiments, the measuring device has in each case a cylindrical housing 1 . In the case of the exemplary embodiment of FIG. 1, the housing 1 is provided with an external thread 11 , by means of which it is screwed into a flange 3 . The latter is mounted on the container on a corresponding counter-flange 4 . In the case of the exemplary embodiment of FIG. 2, the housing 1 is likewise screwed into the flange 3 . The horn 2 b is screwed onto the flange 3 at a later time.
The housing 1 has the shape of a pot or of a tube closed off on one side at the end. The microwaves are generated by a microwave generator (not represented) and are fed via a coaxial line 5 to an exciter element 6 , introduced laterally into the housing 1 . It goes without saying that it is also possible to introduce the exciter element into the housing from one of the end faces. The microwave generator is, for example, a pulsed-radar device, an FMCW device or a continuously oscillating microwave oscillator.
The housing 1 consists of an electrically conductive material, for example aluminum or high-grade steel. The microwaves are transmitted and/or received through the housing 1 via the antenna 2 a or 2 b.
In the case of both exemplary embodiments, in the housing 1 there is arranged an end element 7 , which completely fills an interior space of the housing 1 facing away from the container, apart from a recess which serves for receiving the exciter element 6 . On the side facing the container, a cone is formed onto the end element 7 . An interior space of the housing 1 adjoining said cone is filled by a substantially cylindrical insert 8 . The insert has on its side facing the end element a recess which is identical in shaped to the cone. The insert 8 is screwed into the housing 1 by means of a thread 81 .
In the direction facing the container, there is formed onto the insert 8 a portion 82 of smaller external diameter. this portion has an external thread 83 . In the case of the exemplary embodiment of FIG. 1, the rod-shaped antenna 2 a is screwed onto this external thread 83 . For this purpose, the antenna 2 a has a correspondingly shaped recess, provided with an internal thread. In the case of the exemplary embodiment represented in FIG. 2, a conical end piece 9 , pointing in the direction of the container, is screwed onto the portion 82 .
The sealing of the container takes place in the case of the exemplary embodiment of FIG. 1 by means of an annular disk 2 a 1 , which extends radially outward, is formed onto the rod-shaped antenna 2 a and is clamped between the flange 3 and the counter-flange 4 . In the case of the exemplary embodiment of FIG. 2, an annular disk-shaped seal 10 is provided, which is likewise clamped between the flange 3 and the counter-flange 4 .
The insert 8 consists of a dielectric, which is a composite material composed of a fluoroplastic and ceramic. A fluoroplastic is understood to mean a fluorine-containing polymer, i.e. a polymer with a high proportion of fluorine. The fluoroplastic is preferably polytetrafluoroethylene (PTFE). Likewise very well-suited are modifications of polytetrafluoroethylene (PTFE) in which polytetrafluoroethylene (PTFE) serves as the basic substance.
Examples of this are tetrafluoroethylene-hexafluoroproplyene copolymer (FEP) and perfluoroalkoxy copolymer (PFA). The following description takes polytetrafluoroethylene (PTFE) as an example. This is not to be regarded as a restriction, however.
The end piece 7 likewise preferably consists of this material. In the case of a horn antenna as is represented in FIG. 2, the conical end piece 9 also preferably consists of this composite material.
The proportion of ceramic is preferably below the percolation limit. Below the percolation limit there is no continuous link between the particles of ceramic in the three spatial directions. Depending on the particle size, proportions of ceramic of up to 35 percent by volume are possible as a result.
This achieves the effect that the particles of ceramic are firmly embedded in the polytetrafluoroethylene (PTFE). The composite material consequently has a mechanical strength which substantially corresponds to the strength of polytetrafluoroethylene (PTFE). The material is homogeneous and has a low porosity.
The percolation limit depends on the size of the particles of the two components and can be determined experimentally by determining the dielectric constant or the resistivity of the material as a function of the proportion of ceramic. At the percolation limit, a distinct nonlinear increase in these parameters can be noted.
The ceramic is preferably an aluminum oxide (Al 2 O 3 ), for example corundum. However, barium titanate (BaTi 4 O 9 ), calcium titanate (CaTiO 3 ) or aluminosilicates can also be used.
The dielectric constant of aluminum oxide (Al 2 O 3 ) has a value of approximately ε/ε 0 ≅7; in the case of barium titanate (BaTi 4 O 9 ), this value is ε/ε 0 ≅50 and in the case of calcium titanate (CaTiO3) a value of ε/ε 0 ≅40 to 60 can be obtained. Polytetrafluoroethylene (PTFE) has a dielectric constant of ε/ε 0 ≅2.
The percolation limit for composite material composed of polytetrafluoroethylene and ceramic is at a proportion by volume of about 33% ceramic if the size of the particles of the two components, ceramic and polytetrafluoroethylene (PTFE), is approximately the same.
The dielectric constant of the composite material can be determined to an approximation by linear interpolation. The dielectric constant of the composite material is consequently approximately equal to the weighted sum of the dielectric constants of polytetrafluoroethylene (PTFE) and ceramic, the weighting factors being equal to the proportions by volume V in percent by volume of the components
ε/ε 0 (composite material)≅ε/ε 0 (ceramic)*V(ceramic)+ε/ε 0 (PTFE)*V(PTFE)
The actual values of the dielectric constant ε/ε 0 of the composite material with a proportion of ceramic below the percolation limit are slightly below the values determined by linear interpolation.
If aluminum oxide (Al 2 O 3 ) is used, dielectric constants with values of ε/ε 0 ≅2 to ε/ε 0 ≅5 can be adjusted; if barium titanate (BaTi 4 O 9 ) is used, the adjustable values lie between ε/ε 0 ≅2 and ε/ε 0 ≅33 and, if calcium titanate (CaTiO 3 ) is used, they lie between ε/ε 0 ≅2 and ε/ε 0 ≅30.
Preferably, the value for the dielectric constant ε/ε 0 lies between 2 and 10. As a result of the low dielectric constant, housings 1 with a relatively large internal diameter can be used.
In the case of a dielectric constant of ε/ε 0 ≅4, an internal diameter of about 2 centimeters can be used for transmitting and/or receiving microwaves at a frequency of about 6 GH z . This offers the advantage that inevitable production-related tolerances of the components have minor effects.
A further great advantage of the composite material is that, although it has approximately the mechanical strength of polytetrafluoroethylene (PTFE), the composite material nevertheless has a very much lower coefficient of thermal expansion than polytetrafluoroethylene (PTFE).
The coefficient of thermal expansion of polytetrafluoroethylene is about 150* 10 −6 . The housings 1 typically consist of a high-grade steel. High-grade steel has a coefficient of thermal expansion of 17*10 −6 . The coefficient of thermal expansion of ceramic is of the same order of magnitude as the coefficient of thermal expansion of metal. The coefficient of thermal expansion of a composite material consequently will be much less than the coefficient of thermal expansion of polytetrafluoroethylene (PTFE), according to its proportion of ceramic.
It is ensured by the proportion of ceramic that the insert 8 and housing 1 experience a comparable thermal expansion, so that very much lower temperature-dependant mechanical stresses occur in the housing 1 . The composite material also has a lower pressure- and temperature-dependent tendency to flow than is the case with polytetrafluoroethylene (PTFE). The measuring device can be correspondingly used at higher temperatures and pressures. In comparison with the use of pure ceramic, the composite material additionally offers the advantage that, on account of the polytetrafluoroethylene (PTFE), it is not brittle. There is consequently the possibility of also using relatively large components, such as the rod-shaped antenna 2 a , composed of this material. The use of a hard brittle antenna, for example of pure ceramic, would be problematical, since the antenna could break off under mechanical loading.
The composite material has a loss factor tan δ which is less than one fiftieth. It is ensured by the low loss factor that the microwave power loss is low.
In the case of a rod-shaped antenna 2 a , as is represented in FIG. 1, it may be desired that the rod-shaped antenna 2 a consists of polytetrafluoroethylene (PTFE). This is the case, for example, whenever a measuring device is to be equipped at a later time with an insert 8 composed of the composite material, for example, because the composite material has a more favorable dielectric constant or because the customer would like to use polytetrafluoroethylene (PTFE) exclusively in the container on account of the chemical properties of its filled substance.
To avoid mechanical stresses on account of the different coefficients of thermal expansion of the materials and deformations caused as a result, the insert 8 preferably has in a portion of the housing 1 arranged in the direction of transmission, here in the direction facing away from the antenna, a higher proportion of ceramic than in a portion arranged in the direction of transmission, here facing the antenna. There is consequently a virtually continuous transition, by means of which the advantages of the composite material can be utilized without sudden changes in impedance occurring, which would lead to reflections of microwaves and/or a greater loss factor tan δ.
A composite material composed of ceramic and fluoroplastic, preferably polytetrafluoroethylene (PTFE), is produced by annealing the powdered ceramic, for example aluminum oxide, for example corundum, or some other ceramic, at 800° C. This ensures the detachment of any attached hydroxyl groups.
Here too, the description takes polytetrafluoroethylene as an example. This is not to be regarded as a restriction to this material. The statements made above with respect to fluoroplastics apply correspondingly.
In a next step, polytetrafluoroethylene powder and powdered ceramic are mixed at room temperature. The next process step comprises drying the mixture at 100° C. to 150° C. and pressing the dried mixture into the desired shape under pressure of 500 kg/cm 2 to 1000 kg/cm 2 at room temperature. The pressed blank is sintered for at least five to six hours at 375° C. to 400° C.
If Al 2 O 3 is used, the powdered material should initially be annealed at about 1250° C., subsequently ground for 12 hours, with the addition of water, at room temperature and then dried for 12 hours at 100° C. to 150° C., before the procedure specified above is commenced.
A composite material in which the proportion of ceramic has a gradient can be produced by means of the described process by producing two or more mixtures with different proportions of ceramic, and layering the mixtures one on top of the other before pressing in such a way that the proportion of ceramic in the composite material decreases from layer to layer.
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A description is given of a filling level measuring device operating with microwaves, having a housing and an insert composed of a dielectric, and of a process for producing the dielectric, in which the dielectric constant of the insert is adjustable and in which the insert has a high chemical resistance and a mechanical strength adequate for industrial applications. The dielectric is a composite material composed of a fluoroplastic, in particular polytetrafluoroethylene, and ceramic and is produced by mixing powdered ceramic and powdered fluoroplastic, drying the mixture, pressing the mixture and sintering the pressed mixture.
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CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional Application No. 61/706,690, filed Sep. 27, 2012, the contents of which are expressly incorporated herein by reference.
STATEMENT RE: FEDERALLY SPONSORED RESEARCH/DEVELOPMENT
[0002] Not Applicable
BACKGROUND
[0003] 1. Technical Field
[0004] The present disclosure generally relates to an inlet adapter for use with a fluid testing device, and more specifically, to an inflatable universal inlet adapter configured to form a fluid tight seal with the fluid system under test when the inlet adapter is inflated.
[0005] 2. Related Art
[0006] There are many useful systems which contain and/or operate using a fluid (gas, liquid or combination of both). For example, automobiles have several systems which contain and utilize a fluid in their operation including the fuel system, the exhaust system, the heating, cooling and ventilation (HVAC) system, and the hydraulic power steering and brake systems, to name a few. Moreover, numerous industrial machines, household HVAC systems, and other devices utilize a fluid to operate. Such fluids include, for example, gases such as air or evaporated system liquid, fuel, hydraulic fluids, manufactured gases and liquids, and many other fluids.
[0007] In almost all circumstances, it is important, and in many cases crucial, that these fluid systems be properly sealed to prevent leakage of the system fluid. As an example, in an automobile fuel system, the gas tank and gas lines must be thoroughly sealed to prevent gasoline fumes from polluting the air and also to prevent leaking fuel from creating a fire hazard, not to mention the obvious benefit of conserving gasoline. In HVAC systems, it is important to seal the ducting which transports the conditioned air in order to maintain the efficiency of the systems. Air leaks tend to do nothing but heat or cool an attic, wall interior or other undesired space.
[0008] In many cases, leaks in fluid systems are very difficult to detect and/or locate because the leak is small or in a location not easily accessible. Accordingly, a variety of methods and devices have been devised to detect leaks in fluid systems. The most common leak detectors utilize a visual indicator to locate a leak so that the leak may be repaired. Some of the visual indicators include liquid dyes. The visual indicator is dispensed into the fluid system and leaks are detected by locating places on the system where the visual indicator has escaped the system. For instance, a liquid dye will leave a trace of dye at the leak and smoke will billow out through the leak. Liquid dyes tend to be most useful for detecting leaks in fluid systems which utilize a liquid and are not so useful for gas systems or systems which must seal vapors created by the system fluid. Nevertheless, liquid leaks are typically easier to detect than gas and vapor leaks because the liquid itself is usually visible.
[0009] Vaporized dyes and smoke are generally most useful for detecting leaks in gas systems and systems which have vapors. In some cases, vaporized dye may be added to the smoke such that a trace of dye is left at the leak as the smoke flows through the leak. In general, devices for producing smoke for leak detection comprise a sealed chamber in which smoke is generated by vaporizing a smoke-producing fluid using a heating element. The smoke within the sealed chamber is forced out of the chamber through an outlet port by air pressure from a source of compressed air pumped into the sealed chamber.
[0010] Critical to most any fluid detection system is an inlet adapter which is able to contain the test fluid/vapor at the inlet end. Historically, intake systems and exhaust systems could be effectively tested using EVAP smoke machines that produce smoke at relatively small pressures. Because of the low pressure, smoke could be inserted into the intake/exhaust system via an adapter cone inserted by hand. Leaks in naturally aspirated engines were routinely detected via this method very effectively.
[0011] However, boosted engines (with turbochargers or supercharges) have leaks that are typically present under load where the boost can be 10 PSI to 15 PSI, or in some cases over 20 PSI. These types of tiny leaks only make themselves known at high pressures (e.g., 10-20 PSI or higher).
[0012] In view of these high pressure requirements, high pressure diagnostic leak detectors have been developed which produce smoke at elevated pressures for testing the fluid integrity of the fluid system. Inlet adapters are typically used with these high pressure diagnostic leak detectors; however, the inlet adapters are typically customized for use with a fluid system having conduits which are of a specific size and configuration.
[0013] Accordingly, there is a need in the art for a universal inlet adapter configured to deliver pressurized smoke into most all fluid systems. The present invention addresses this need, as will be discussed in more detail below.
BRIEF SUMMARY
[0014] According to an aspect of the invention, there is provided a balloon-type catheter apparatus which is conformable to fit most all intake and exhaust systems to deliver pressure (with or without smoke) to test the fluid integrity of the fluid system. The device is configured to be inserted into the canal of the intake or exhaust system and inflated to seal off the fluid system. The pressurized smoke is passed through the inflated inlet adapter to test for leaks.
[0015] One embodiment of the present invention includes a universal inlet adapter for a leak detection device using a pressurized detection media for detecting a leak in a fluid system having a fluid duct. The universal inlet adapter comprises an inflatable bladder selectively transitional between an inflated configuration and a deflated configuration. The inflatable bladder is configured to be engagable with the fluid duct to form a fluid tight seal therebetween as the inflatable bladder transitions from the deflated configuration to the inflated configuration. The universal inlet adapter further includes a test fluid delivery tube extending through the inflatable bladder such that the inflatable bladder is disposed radially outward from the test fluid delivery tube. The test fluid delivery tube is fluidly connectable with the leak detection device for delivering the pressurized detection media into the fluid duct for testing.
[0016] The inflatable bladder may define an internal bladder reservoir, and the test fluid delivery tube may traverse through the internal bladder reservoir. The inflatable bladder may be conformable to the shape of the fluid duct as the inflatable bladder transitions from the deflated configuration to the inflated configuration. The inflatable bladder may define a tubular configuration.
[0017] The test fluid delivery tube may be co-axially aligned with the bladder. The test fluid delivery tube is an elongate rigid tube. The test fluid delivery tube may define an internal passageway fluidly isolated from the internal bladder reservoir.
[0018] The universal inlet adapter may additionally include an inflation conduit fluidly connected to the inflatable bladder and fluidly connectable to a pressurized fluid source for selectively transitioning the inflatable bladder from the deflated configuration to the inflated configuration. A hand pump may be fluidly coupled or connectable to the inflation conduit for delivering fluid into the inflatable bladder for causing the inflatable bladder to transition from the deflated configuration to the inflated configuration.
[0019] The universal inlet adapter may additionally include a pair of rigid end caps connected to the inflatable bladder at opposed end portions of the inflatable bladder. A pair of locking rings may cooperate with respective ones of the pair of rigid end caps to secure the bladder therebetween. The pair of rigid end caps may include a first rigid end cap and a second rigid end cap, wherein the first rigid end cap is connected to the test fluid delivery tube and the inflation conduit, and the second rigid end cap is connected to the test fluid delivery tube. The pair of rigid end caps and the test fluid delivery tube may be threadedly engageable.
[0020] According to another embodiment, there is provided a method of testing the fluid integrity of a fluid system having a fluid duct. The method includes providing a leak detection device including an inflatable bladder selectively transitional between an inflated configuration and a deflated configuration, wherein the inflatable bladder is configured to be engagable with the fluid duct to form a fluid tight seal therebetween as the inflatable bladder transitions from the deflated configuration to the inflated configuration, and a test fluid delivery tube extending through the inflatable bladder such that the inflatable bladder is disposed radially outward from the test fluid delivery tube. The method additionally includes inserting the leak detection device into the fluid duct and inflating the inflatable bladder to create a fluid tight seal between the inflatable bladder and the fluid duct. The method further includes directing a test media into the fluid system via the test fluid delivery tube.
[0021] The inserting step may include inserting the leak detection device into the fluid duct such that a majority of the bladder is inserted into the fluid duct.
[0022] The inflating step may include using a hand pump to inflate the inflatable bladder. The inflating step may include inflating the bladder to a pressure greater than the pressure of the test media. The inflating step and the directing steps may result in the creation of a pressure differential within the fluid duct on opposed sides of the bladder.
[0023] The method may additionally include the step of fluidly connecting the test fluid delivery tube to the test media. The method may further comprise the steps of deflating the bladder from the inflated position to the deflated position to break the fluid-tight seal between the bladder, and removing the leak detection device from the fluid duct.
[0024] The presently contemplated embodiments will be best understood by reference to the following detailed description when read in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] These and other features and advantages of the various embodiments disclosed herein will be better understood with respect to the following description and drawings, in which:
[0026] FIG. 1 is an upper perspective view of a universal inlet adapter configured for use with a pressurized test media for testing the fluid integrity of a fluid system;
[0027] FIG. 2 is a side sectional view of the universal inlet adapter in a deflated configuration and inserted within a fluid duct of the fluid system; and
[0028] FIG. 3 is a side sectional view of the universal inlet adapter depicted in FIG. 2 , with the universal inlet adapter depicted in the inflated configuration.
[0029] Common reference numerals are used throughout the drawings and the detailed description to indicate the same elements.
DETAILED DESCRIPTION
[0030] The detailed description set forth below in connection with the appended drawings is intended as a description of the presently preferred embodiments of the invention, and is not intended to represent the only form in which the present devices may be developed or utilized. It is to be understood, however, that the same or equivalent functions may be accomplished by different embodiments that are also intended to be encompassed within the spirit and scope of the invention. It is further understood that the use of relational terms such as first, second, and the like are used solely to distinguish one from another entity without necessarily requiring or implying any actual such relationship or order between such entities.
[0031] Referring now to the drawings, wherein the showings are for purposes of illustrating a preferred embodiment of the present invention only, and are not for purposes of limiting the same, there is depicted a universal and inflatable inlet adapter 10 for use with a fluid leak detector. The inlet adapter 10 is configured to assume a deflated configuration to define a small profile to facilitate insertion of the inlet adapter 10 into a fluid system 12 for testing. Once inserted, the inlet adapter 10 is selectively transitional from the deflated configuration to an inflated configuration, wherein the inlet adapter 10 expands so as to create a fluid-tight seal between the inlet adapter 10 and the fluid system 12 . The inlet adapter 10 is further configured to deliver test media 14 (e.g., smoke) into the fluid system 12 for identifying potential leaks within the system 12 .
[0032] The inflatable inlet adapter 10 is configured to be conformable to the unique size and configuration of a fluid duct 16 (e.g., intake or exhaust) of the fluid system 12 being tested. In this regard, the degree to which the inlet adapter 10 is inflated typically depends directly on the size of the opening 18 defined by the fluid duct 16 . The inlet adapter 10 will generally be inflated to a lesser degree for smaller fluid ducts 16 , and to a greater degree for larger fluid ducts 16 . Furthermore, the inflatable portion of the inlet adapter 10 will generally conform to the specific shape of the duct opening 18 to create a strong, fluid-tight seal between the fluid duct 18 and the inlet adapter 10 .
[0033] The inlet adapter 10 includes an inflatable bladder 20 selectively transitional between the inflated configuration and the deflated configuration. The inflatable bladder 20 defines an internal bladder reservoir 22 which expands as the bladder 20 transitions from the deflated configuration toward the inflated configuration. The inflatable bladder 20 is preferably formed from an expandable, resilient and durable material capable of being inserted within fluid systems for testing. Along these lines, the material used to form the bladder 20 should have a sufficient thickness which provides strength and durability to the bladder 20 so as to mitigate inadvertent rupturing of the bladder 20 , while at the same time allowing the bladder 20 to be flexible enough so as to generally conform to the unique shape of the fluid duct 16 as the bladder 20 transitions to the inflated configuration.
[0034] The exemplary bladder 20 depicted in the Figures is formed from a generally cylindrical sleeve having an opening extending through the sleeve. The bladder 20 preferably engages with a pair of rigid end caps 32 , 34 at opposed ends of the bladder 20 , as will be described in more detail below.
[0035] The universal inlet adapter 10 further includes a test fluid delivery tube 24 extending through the inflatable bladder 20 for delivering the pressurized detection media 14 (e.g., smoke) into the fluid duct 16 for testing. The test fluid delivery tube 24 includes a first end portion 26 connectable to the leak detection device to receive a pressurized testing media 14 therefrom, and an opposing second end portion 28 configured to deliver the pressurized test media 14 into the fluid duct 16 for testing. The test fluid delivery tube 24 defines an internal passageway fluidly 30 isolated from the internal bladder reservoir 22 and extending between the first and second end portions 26 , 28 .
[0036] According to one embodiment the test fluid delivery tube 24 is an elongate rigid tube extending through the bladder reservoir 24 , and co-axially aligned with the bladder 20 such that the inflatable bladder 20 is disposed radially outward from the test fluid delivery tube 24 . The test fluid delivery tube 24 may include a nipple or fluid connector 25 disposed adjacent the first end portion 26 and being fluidly connectable with the testing device for receiving the testing media 14 therefrom.
[0037] The universal inlet adapter 10 may additionally include a pair of rigid end caps 32 , 34 connected to the inflatable bladder 20 at opposed end portions of the inflatable bladder 20 . A first rigid end cap 32 is connected to the test fluid delivery tube 24 adjacent the first end portion 26 thereof and a second rigid end cap 34 is connected to the test fluid delivery tube 24 adjacent the second end portion 28 thereof. The end caps 32 , 34 include respective insertion portions 31 , 33 insertable into the bladder opening at respective ends of the bladder 20 . Flange portions 35 , 37 extend radially outward from respective insertion portions 31 , 33 and preferably define a perimeter or diameter that is larger than the perimeter/diameter of the bladder 20 at the end portions.
[0038] In the exemplary embodiment, the test fluid delivery tube 24 is externally threaded at the first and second end portions 26 , 28 , while the first and second end caps 32 , 34 include apertures which are internally threaded. The external threads on the test fluid delivery tube 24 engage with the internal threads formed on the rigid end caps 32 , 34 to connect the end caps 32 , 34 to the test fluid delivery tube 24 . The threaded engagement between the test fluid delivery tube 24 and the rigid end caps 32 , 34 preferably forms a fluid-tight seal between the test fluid delivery tube 24 and the rigid end caps 32 , 24 to allow the bladder 20 to be inflated without fluid leaking through the interface between the delivery tube 24 and the end caps 32 , 34 . It is contemplated that a sealant may be used to strengthen the fluid-tight engagement between the delivery tube 24 and the end caps 32 , 34 .
[0039] A pair of locking rings 36 , 38 may be used to connect the inflatable bladder 20 to the end caps 32 , 34 . Each locking ring 36 , 38 cooperates with one of the pair of rigid end caps 32 , 34 to secure the inflatable bladder 20 between the locking rings 32 , 34 and the end caps 36 , 38 . The locking rings 36 , 38 fit over respective insertion portions 31 , 33 of the end caps 32 , 34 and may be positioned adjacent to or in abutting relation with the respective flange portion 35 , 37 of the end caps 32 , 34 . The locking rings 36 , 38 may define an outer diameter that is flush with the outer diameter of the corresponding flange portion 35 , 37 . Furthermore, the locking rings 36 , 38 may include smooth inner diameters which force contact at the tips of the barbs formed on the outer diameter of insertion portions 31 , 33 to create an air tight seal. As the bladder 20 inflates, the expanding bladder 20 forces and holds the rings 36 , 38 in place
[0040] The engagement of the end caps 32 , 34 to the delivery tube 24 preferably fixes the axial length of the inlet adapter 10 , such that when the bladder 20 is inflated, the bladder 20 expands radially outward, rather than expanding in an axial dimension.
[0041] The universal inlet adapter 10 may additionally include an inflation conduit 40 fluidly connected to the inflatable bladder 20 and fluidly connectable to a pressurized fluid source for selectively transitioning the inflatable bladder 20 from the deflated configuration to the inflated configuration. The inflation conduit 40 extends through the first end cap 32 to deliver pressurized fluid from the fluid source into the bladder 20 .
[0042] A hand pump 42 may be fluidly coupled or connectable to the inflation conduit 40 for inflating the bladder 20 . In the exemplary embodiment, the hand pump 42 includes a pumping mechanism 44 and a pump conduit 46 for delivering pressurized fluid (e.g., air) into the bladder reservoir 22 . The hand pump 42 may also include a release valve 45 for releasing fluid from the bladder 20 during deflation thereof. Although the exemplary embodiment includes a hand pump 42 for inflating the bladder 20 , those skilled in the art will appreciate that an electrical pump may also be used for inflating the bladder 20 .
[0043] Although the exemplary embodiment includes rigid end caps 32 , 34 , it is contemplated that other embodiments of the inlet adapter 10 may not include rigid end caps 32 , 34 . In this regard, the bladder 20 may be coupled directly to the delivery tube 24 , and may include an inflation port integrated into the bladder 20 for inflation. Furthermore, it is also contemplated that other embodiments may include a hybrid design wherein a single rigid end cap is used at one end of the bladder 20 , while the opposing end of the bladder 20 is formed without an end cap.
[0044] With the basic structural features of the inlet adapter 10 described above, the following discussion focuses on use of the inlet adapter 10 for testing the fluid integrity of the fluid system 12 . With the bladder 20 in the deflated configuration, the inlet adapter 10 is inserted into the duct opening 18 such that a majority of the bladder 20 is inserted into the fluid duct 16 . In this regard, a sufficient amount of the bladder 20 is inserted into the duct 16 so as to allow the bladder 20 to create a fluid tight seal between the bladder 20 and the inner surface 48 of the duct 16 .
[0045] The inflatable bladder 20 is then inflated to create a fluid tight seal between the inflatable bladder 20 and the inner surface 48 of the fluid duct 16 . As can be seen in FIG. 3 , when the inflatable bladder 20 is inflated and begins to interface with the inner surface 48 of the fluid duct 16 , the bladder 20 begins to conform to, or assume the shape of the inner surface 48 of the bladder 20 . In particular, the pressure within the bladder 20 shown in FIG. 3 has caused the bladder 20 to engage with the inner surface 48 and to define a flattened region 50 that has assumed the shape of the inner surface 48 .
[0046] As noted above, inflation of the bladder 20 may be achieved through the use of a hand pump 42 , or an electrical pump, or via other inflation means known by those skilled in the art. Preferably, the bladder 20 is inflated to an internal pressure which is greater than the testing pressure so as to anchor the bladder 20 firmly within the fluid duct 16 during testing.
[0047] The method further includes directing the pressurized test media 14 into the fluid system 12 via the test fluid delivery tube 24 . The pressurized test media 14 may be directed into the fluid system 12 by connecting the test fluid delivery tube 24 to testing device.
[0048] When the bladder 20 is inflated and the pressurized media 14 is directed into the fluid system 12 , a pressure differential may be created within the fluid duct 16 on opposed sides of the bladder 20 . In particular, the pressure within the fluid duct 16 on the downstream side of the bladder 20 (e.g., the side to which the pressurized media 14 is emitted) is greater than the pressure within the fluid duct 16 on the opposed side of the bladder 20 . The fluid-tight seal between the bladder 20 and the duct 16 allows the creation of the pressure differential for conducting the fluid integrity testing.
[0049] It is contemplated that the fluid integrity testing may be conducted at various pressures, preferably in the range of 0.5-20 PSI, although those skilled in the art will recognize that tests performed at pressures outside of exemplary pressure range may also be conducted without departing from the spirit and scope of the present invention. Elevated testing pressures (i.e., 10-20 PSI) are preferable for boosted engines (with turbochargers or superchargers), wherein the leaks may only be detectable at such high pressures.
[0050] Once the testing is complete, the bladder 20 may be transitioned from the inflated position to the deflated position to break the fluid-tight seal between the bladder 20 and the fluid duct 16 , and to facilitate removal of the inlet adapter 10 from the fluid duct 16 .
[0051] The particulars shown herein are by way of example and for purposes of illustrative discussion of the embodiments of the present invention only and are presented in the cause of providing what is believed to be the most useful and readily understood description of the principles and conceptual aspects. In this regard, no attempt is made to show more details than is necessary for a fundamental understanding of the disclosure, the description taken with the drawings making apparent to those skilled in the art how the several forms of the presently disclosed invention may be embodied in practice.
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An inflatable, balloon-type catheter apparatus which is conformable to fit most all intake and exhaust systems to delivery pressure (with or without smoke) to test the fluid integrity of the fluid system. The device is configured to be inserted into the canal of the intake or exhaust system and inflated to seal off the fluid system. The pressurized smoke is passed through the inflated inlet adapter to test for leaks.
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CROSS-REFERENCE TO RELATED APPLICATION
The present application is a divisional of patent application Ser. No. 12/004,880 entitled “Method and apparatus for mechanically splicing optic fibers,” filed 24 Dec. 2007 now U.S. Pat. No. 7,918,612, which in turn claims the benefit of Provisional Patent Application No. 60/924,692 entitled “Compact and curable work station for fiber splice,” filed 29 May 2007, both of which are incorporated by reference herein in their entirety for all purposes.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
The U.S. Government has a paid-up license in this invention and the right in limited circumstances to require the patent owner to license others on reasonable terms as provided for by the terms of Contract No. N68335-05-C-0308 awarded by the U.S. Department of the Navy.
BACKGROUND OF THE INVENTION
1. Field of Invention
The present invention relates to optic fiber splicing and, in particular, to a method and apparatus for mechanically splicing optic fibers.
2. Description of the Background Art
Fusion splicing of optic fiber has been utilized in connecting optic fibers for a wide variety of optic devices, and has also been used for the installation of fiber spans for telecommunications networks. In most such application, the fusion splicing process is preferred over other methods to achieve minimum insertion loss and long term reliability. However, for some applications a mechanical splicing process may present a low-cost and convenient alternative that can accommodate many types of optic fibers. In particular, the mechanical splicing alternative is often the preferred choice for applications in which the work environment presents a fire or explosive hazardous, such as in an aircraft, around oil stations, and in mines. In such hazardous applications, the use of a high-voltage fusion splicing device is typically prohibited for safety reasons.
Optic fiber mechanical splicing devices are known in the prior art. Conventional mechanical splicers are typically based on a V-groove seating configuration and, accordingly, are typically used only for temporary fiberoptic connections because of associated unproven long term reliability concerns. With respect to these reliability concerns, two primary long-term failure mechanisms have been identified in optic fiber components: material deterioration caused by prolonged humidity exposure and joint fatigue caused by extended thermal cycling induced stress as well as relative movement between subcomponents. These two failure mechanisms need to be addressed in the industry if the fundamental design objectives are to realize a twenty-five year component operation life and high reliability fiberoptic components.
The process of optic fiber splicing typically includes several manual steps and involves extensive fiber handling among multiple pieces of processing equipment. The fiber splicing preparation may include: fiber stripping, fiber tip cleaning, fiber cleaving, fiber aligning, fiber securing and fiber splice packaging. Each of these process steps requires manual loading, unloading, and other manual process steps. The manipulation and handling of the fibers throughout these process steps compromises fiber strength and may lead to failure during subsequent use.
What is needed is a method and apparatus using an integral precision fiber alignment feature to easily and quickly produce a permanent mechanical splice for optic fibers.
SUMMARY OF THE INVENTION
In one aspect of the present invention, device for mechanically splicing a first optic fiber to a second optic fiber comprises: a ferrule having an axial capillary bore, the capillary bore configured to enclose the first optic fiber at a first end of the ferrule and to enclose the second optic fiber at a second end of the ferrule; and cured epoxy disposed to secure an end of the first optic fiber to an end of the second optic fiber, the cured epoxy further disposed to secure the first optic fiber and the second optic fiber to an inside surface of the capillary bore.
In another aspect of the present invention, an apparatus for splicing a first optic fiber to a second optic fiber comprises: a first clamp secured to the first optic fiber; a second clamp secured to the second optic fiber, the first and second clamps for retaining an end of the first optic fiber against an end of the second optic fiber; and an ultraviolet light source disposed to irradiate epoxy disposed between the end of the first optic fiber and the end of the second optic fiber.
In another aspect of the present invention, a method for splicing optic fibers comprises the steps of: providing epoxy in a capillary bore of a ferrule; placing an end of a first optic fiber against an end of a second optic fiber in the epoxy inside the capillary bore; and curing the epoxy.
The additional features and advantage of the disclosed invention is set forth in the detailed description which follows, and will be apparent to those skilled in the art from the description or recognized by practicing the invention as described, together with the claims and appended drawings.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagrammatical illustration of two optic fibers secured within a ferrule to form a mechanical splice shown in partial cross section, in accordance with the present invention;
FIG. 2 is a cross-sectional diagrammatical illustration of the mechanical splice of FIG. 1 showing a square capillary bore with four micro channels in the ferrule;
FIG. 3 is a cross-sectional diagrammatical illustration of an alternative embodiment of the mechanical splice of FIG. 1 showing a triangular capillary bore with three micro channels in the ferrule;
FIG. 4 is a simplified diagram of one embodiment of a workstation having an ultraviolet light module suitable for fabricating the mechanical splice of FIG. 2 , in accordance with the present invention;
FIG. 5 is a diagrammatical illustration of the ultraviolet light module of FIG. 4 showing a cylindrical lens used to direct ultraviolet light;
FIG. 6 is a side view of a portion of an alternative embodiment of a UV module for the workstation of FIG. 4 ;
FIG. 7 is a diagrammatical illustration of the ultraviolet light module of FIG. 6 showing a reflector used to direct ultraviolet light;
FIG. 8 is a cross-sectional diagrammatical illustration of an alternative embodiment of the mechanical splice of FIG. 1 showing an oval capillary bore with two micro channels in the ferrule;
FIG. 9 is a cross-sectional diagrammatical illustration of an alternative embodiment of the mechanical splice of FIG. 1 showing an elongated capillary bore with one micro channel in the ferrule;
FIG. 10 is a cross-sectional diagrammatical illustration of an alternative embodiment of the mechanical splice of FIG. 1 showing a ferrule with an offset section;
FIG. 11 is a cross-sectional diagrammatical illustration of the mechanical splice of FIG. 10 showing a triangular capillary bore having relaxed fabrication tolerances;
FIG. 12 is a cross-sectional diagrammatical illustration of an alternative embodiment of the mechanical splice of FIG. 10 showing a square capillary having relaxed fabrication tolerances;
FIG. 13 is an alternative embodiment of the mechanical splice of FIG. 1 showing a metal tube enclosing the ferrule; and
FIG. 14 is a flow diagram explaining a process for fabricating the mechanical splices of FIGS. 1 and 13 .
DETAILED DESCRIPTION OF THE INVENTION
The following detailed description is of the best currently contemplated modes of carrying out the invention. The description is not to be taken in a limiting sense, but is made merely for the purpose of illustrating the general principles of the invention, since the scope of the invention is best defined by the appended claims.
The present invention is a method and apparatus for efficiently producing a permanent, high reliability mechanism splice for optic fiber applications. The disclosed mechanical splice design has been shown to successfully pass standard industry environmental tests, including vibration and thermal shock, to qualify for permanent installation application. Moreover, the disclosed design uses a glass seal technology to permanently encapsulate components in a ferrule. For more demanding environmental conditions, or for application to fiber cable designs, a metal tube may be positioned and crimped to enclose the ferrule to withstand tensile forces in the optic fiber cable.
This feature provides high reliability even when humidity is a concern, for example, as exemplified by having successfully passed high pressure autoclave humidity testing of 120° C. and 100% relative humidity for a one week cycle. In addition, the disclosed mechanical splice design uses glass material with a coefficient of thermal expansion matched to the optic fibers to mitigate or eliminate the progressive damage caused by thermal cycling, and to provide temperature stability performance.
The disclosed ferrule design provides passive precision self-alignment for an inserted optic fiber core and guided fiber insertion. The ferrule comprises a material substantially transparent to ultraviolet radiation to allow for an integrated ultraviolet epoxy curing capability. One design feature of the disclosed fiber guide ferrule allows for the insertion of polyimide-coated fiber directly without the need to first strip the hard resin buffer material layer. This approach is versatile and applies to a wide variety of the fibers found in military aviation including both multi-mode and single-mode fibers. The ferrule includes a non-circular capillary bore forming one or more axial micro channels when the optic fibers are inserted. The micro channels allow an outflow of excess epoxy and air bubbles when two optic fibers are inserted into the epoxy contained in the ferrule. By using refractive index matching of the epoxy and ferrule, and by applying an axial load to minimize the space between the ends of the two optic fibers, an extremely low optic loss can be achieved between the fibers, to as little as 0.05 dB or less.
There is shown in FIGS. 1 and 2 an exemplary embodiment of a mechanical splice 20 , in accordance with the present invention. The mechanical splice 20 functions to connect a first optic fiber 11 to a second optic fiber 13 by providing a permanent splice with a low fiber insertion loss. The mechanical splice 20 comprises a ferrule 21 with a capillary bore 23 axially extending between a first ferrule end 25 and a second ferrule end 27 . As best seen in FIG. 2 , the capillary bore 23 may have a non-circular cross-section in the general shape of a four-sided polygon, such as a trapezoid or square. The capillary bore 23 is configured to allow insertion of the first optic fiber 11 and the second optic fiber 13 into the ferrule 21 , as shown.
The specified size of the capillary bore 23 is large enough to allow the first optic fiber 11 and the second optic fiber 13 to be inserted into and guided through the opposite ferrule ends 25 and 27 without breakage or binding. The size of the capillary bore 23 is further small enough to provide for close retention of the optic fibers 11 and 13 inside the capillary bore 23 and thus provide for precise relative alignment of the respective fiber cores when an end face 15 of the first optic fiber 11 makes contact with an end face 17 of the second optic fiber 13 . In the example provided, the capillary bore 23 is shaped such that the optic fibers 11 and 13 contact the perimeter of the capillary bore 23 at up to four circumferential regions and are thus restrained from misalignment. The ferrule 21 may include lead-in funnel-like or concave conical openings 19 at the ferrule ends 25 and 27 , to provide improved fiber guidance when the optic fibers 11 and 13 are being inserted into the ferrule 21 .
The above configuration of the capillary bore 23 further provides micro channels 31 , 33 , 35 , and 37 as internal volumes for retaining an epoxy 41 . As explained in greater detail below, the micro channels 31 , 33 , 35 , and 37 also function as conduits to allow or enable excess epoxy 41 to flow out of the ferrule 21 as the optic fibers 11 and 13 are being inserted into the ferrule 21 . A thin layer 43 of the epoxy 41 is retained between the end face 15 of the first optic fiber 11 and the end face 17 of the second optic fiber 13 after the optic fibers 11 and 13 have been inserted into the ferrule 21 . The thin layer 43 of the epoxy 41 thus functions to mechanically secure the end face 15 of the optic fiber 11 to the end face 17 of the optic fiber 13 . The epoxy 41 remaining in the micro channels 31 , 33 , 35 , and 37 function to secure the outer surface of the first optic fiber 11 and the outer surface of the second optic fiber 13 to the ferrule 21 .
In an exemplary embodiment, the index of refraction of the epoxy 41 is substantially the same as, or closely matched to, the index of refraction of the cores of the optic fibers 11 and 13 to assure minimal insertion loss of signal at the interface between the end face 15 and the end face 17 . The insertion loss may be further minimized by maintaining a close tolerance on the size of the capillary bore 23 so as to provide precise alignment of the respective fiber optic cores. Preferably, the thermal coefficient of expansion of the epoxy 41 is closely matched to the thermal coefficients of expansion of the optic fibers 11 and 13 , and the thermal coefficient of expansion of the material used for the ferrule 21 is also closely matched to the thermal coefficient of expansion of the optic fibers 11 and 13 . This thermal coefficient matching serves to minimize thermal stresses in the mechanical splice 20 produced when the ambient temperature varies.
In an alternative exemplary embodiment, shown in the cross-sectional diagram of FIG. 3 , a ferrule 51 comprises a capillary bore 53 having a non-circular cross sectional shape of a three-sided polygon, or triangle. It should be understood that the shape of the capillary bore 53 need not be an equilateral triangle, and that the vertices of the triangular capillary may be rounded, as shown, in accordance with fabrication preference. The size of the capillary bore 53 is preferably specified such that the first optic fiber 11 and the second optic fiber 13 can make contact with each other inside the ferrule 51 with precise relative alignment of the respective fiber cores, as discussed above for the ferrule 21 . That is, the optic fibers 11 and 13 contact the perimeter of the capillary bore 53 at three circumferential regions to insure the proper relative alignment.
The capillary bore 53 is further configured to provide micro channels 55 , 57 , and 59 as internal volumes for retaining the epoxy 41 , where the specific sizes, shapes, and relative positions of the micro channels 55 , 57 , and 59 depend upon the ferrule design and fabrication processes. The micro channels 55 , 57 , and 59 similarly serve as conduits to allow or enable excess epoxy 41 to flow out of the ferrule 51 as the optic fibers 11 and 13 are being inserted into the ferrule 51 . The epoxy 41 splices the first optic fiber 11 to the second optic fiber 13 in the ferrule 51 .
An exemplary embodiment of a mechanical splicing apparatus 60 , or curing station, for producing the mechanical splice 20 is shown in the diagram of FIG. 4 . The apparatus 60 comprises a first detachable clamp 61 removably mounted to a guide 39 on a base 65 , and a second detachable clamp 63 slidably mounted to a guide 49 on the base 65 . An ultraviolet light module 70 is mounted to the base 65 between the first detachable clamp 61 and the second detachable clamp 63 . An elastic component, such as a spring 69 , is connected to the ultraviolet light module 70 and to the second detachable clamp 63 as shown in the diagram. The ultraviolet light module 70 is configured to retain and irradiate a ferrule in position for insertion of the optic fibers 11 and 13 . In an exemplary embodiment, the emplaced ferrule may be the ferrule 21 , as shown, the ferrule 51 described above, or either ferrule 111 or ferrule 121 described below.
The first detachable clamp 61 may be used to secure and position the first optic fiber 11 , and the second detachable clamp 63 may be used to secure and position the second optic fiber 13 , as shown in the diagram. Stripping, cleaning, and cleaving processes may be performed on the optic fibers 11 and 13 , if desired, while secured in the respective clamps 61 and 63 before attachment to the base 65 . Both the first detachable clamp 61 and the second detachable clamp 63 can be moved along the base such that the first optic fiber 11 and the second optic fiber 13 can be positioned for insertion into the emplaced ferrule 21 while being held in the respective detachable clamps 61 and 63 .
When the first detachable clamp 61 is fixed to the guide 39 on the base 65 and the second detachable clamp 63 is allowed to slide along the guide 49 , the spring 69 functions to provide a precisely controlled, predetermined force for urging the second detachable clamp 63 toward the fixed first detachable clamp 61 , an action which causes the end 17 of the second optic fiber 13 to be controllably and precisely forced against the end 15 of the first optic fiber 11 inside the ferrule 21 .
The ultraviolet light module 70 comprises an ultraviolet light source, such as one or more UV lasers (not shown) or UV LEDs 71 (as shown). Some of the ultraviolet light from the UV LEDs 71 may be directly focused onto the epoxy 41 in the ferrule by passing the light through a converging cylindrical lens 73 , as shown in greater detail in the diagram of FIG. 5 . Other ultraviolet light from the UV LEDs 71 may be scattered from a reflector 75 to additionally irradiate other areas of the epoxy 41 upon reflection. The UV LEDs 71 may be disposed proximate a UV-transparent window 77 to allow for positioning of the ferrule 21 proximate the ultraviolet light sources 71 .
The ultraviolet light sources in the ultraviolet light module 70 are powered by a power source, such as a rechargeable cell or battery 45 (shown in FIG. 6 ). Control electronics 47 (shown in FIG. 6 ) may be provided to control the exposure time and intensity of the UV LEDs 71 or UV diodes (if used). In an exemplary embodiment, a switch (not shown) is provided to allow an operator to apply a pre-set amount of power to the UV LEDs 71 or to the UV laser diodes. The operating intensity of the ultraviolet radiation may also be pre-set in the control electronics 47 . It can be appreciated that, by providing UV LEDs as a source of ultraviolet light and a battery as a source of power, the mechanical splicing apparatus 60 may be configured as a compact, portable mechanical splicing device suitable for field applications.
FIGS. 6 and 7 illustrate an alternate exemplary embodiment of an ultraviolet light module 80 that can be attached to the base 65 in place of the ultraviolet light module 70 . A ferrule, such as the ferrule 21 , may be secured in the ultraviolet light module 80 by mounting in a V-shaped ferrule clamp 89 . Ultraviolet light, provided by the UV LEDs 71 , may be reflected from a primary reflector, such as a cylindrical mirror 81 , on to the epoxy 41 in the ferrule 21 . The cylindrical mirror 81 may be rotatable about a pivot 85 to allow for emplacement and removal of the ferrule 21 from the ultraviolet light module 80 . Stray ultraviolet light may be reflected to the epoxy by a secondary reflector 83 disposed proximate the ferrule 21 , as best seen in the diagrammatical representation of FIG. 7 . The ultraviolet LEDs 71 may be positioned against a UV-transparent glass plate 87 for alignment purposes. Operation of the ultraviolet LEDs 71 may be controlled and powered by the control electronics 47 and the battery 45 , as described above.
An alternative exemplary embodiment of a ferrule 91 , shown in FIG. 8 , may comprise a capillary bore 93 having an oval or elliptical shape. The size of the capillary bore 93 is specified such that each of the first optic fiber 11 and the second optic fiber 13 can make contact at two circumferential regions, as shown, to provide for precise relative alignment of the respective fiber cores, as discussed above. In the configuration shown, a first micro channel 95 and a second micro channel 97 are provided for outflow of excess epoxy 41 .
In yet another exemplary embodiment, shown in FIG. 9 , a ferrule 101 may comprise a capillary bore 103 having an elongated non-circular shape. The capillary bore 103 provides a single micro channel 105 for excess epoxy 41 . It should be understood that the inside configuration of the greater portion of the capillary bore 103 closely approximates the geometry of the outside surfaces of the optic fibers 11 and 13 . The gap shown between the optic fiber 11 and the capillary bore 103 has accordingly been exaggerated to more clearly illustrate this feature.
FIG. 10 shows a cross-sectional view of an alternative exemplary embodiment of a ferrule 111 (and a ferrule 121 ) having an offset section 113 for providing precise fiber optic alignment with capillary bores that have reduced fabrication tolerances. The offset section 113 has an offset length “L” displaced at an offset distance 119 , where the offset length L and the offset distance 119 may be determined as a function of optic fiber parameters and epoxy material properties. In an exemplary embodiment, the offset distance 119 may be in the range of 20-30 μm.
FIG. 11 is a cross sectional view of the offset section 113 of the ferrule 111 showing the optic fiber 13 emplaced in a triangular capillary bore 115 having relaxed fabrication tolerances. Accordingly, the optic fiber 13 is forced against a micro channel 117 by virtue of the geometry of the offset section 113 . In this configuration, the optic fiber 13 contacts an inside vertex of the triangular bore 115 at two circumferential regions, in the direction of the offset section 113 . It can be appreciated that the space between the optic fiber 13 and the inside surface of the triangular capillary bore 115 contains the epoxy 41 . Likewise, FIG. 12 shows a cross sectional view of an offset ferrule 121 having a square capillary bore 123 with reduced fabrication tolerances. In this configuration, the optic fiber is urged in the direction of the offset to form a micro channel 125 , and contacts the inside surface of the square capillary bore 123 at two circumferential regions. It can be appreciated that the region between the optic fiber 13 and the inside surface of the square capillary bore 123 , which has been exaggerated for clarity of illustration, contains the epoxy 41 .
FIG. 13 shown an exemplary embodiment of a mechanical splice 140 for joining jacketed optic fiber cable, such as a first optic cable 131 and a second optic cable 141 . The mechanical splice 140 comprises a protective metal tube 150 as an environmental enclosure for the ferrule, here shown as the ferrule 21 , although it should be understood that any of the ferrule 51 , the ferrule 111 , and the ferrule 121 , or any other suitable ferrule, can be used as well. The mechanical splice 140 further functions to withstand a tensile force that may be applied to either or both the first optic cable 131 and the second optic cable 141 during laying, pulling, or other installation procedures, for example.
As typically configured in the present state of the art, the first optic cable 131 may comprise an optic fiber 133 , a resin buffer layer 135 , a flexible fibrous polymer 137 , such as Kevlar®, and an outer jacket layer 139 , such as a plastic. The second optic cable 141 may similarly comprise an optic fiber 143 , a resin buffer layer 145 , a flexible fibrous polymer 147 , and an outer jacket layer 149 . The resin buffer layer 135 and the resin buffer layer 145 are removed from the portions of the optic fiber 133 and the optic fiber 143 , respectively, to allow for insertion into the ferrule 21 , or another ferrule that may be used. The epoxy 41 secures the outer surface of the optic fiber 133 and the outer surface of the optic fiber 143 to the ferrule 21 , and the thin layer 43 of the epoxy 41 is retained between the optic fiber 133 and the optic fiber 143 , as described above for the mechanical splice 20 .
An internal sleeve 151 is inserted between the resin buffer layer 135 and the fibrous polymer 137 , and another internal sleeve 151 is inserted between the resin buffer layer 145 and the flexible fibrous polymer 147 . An outer sleeve 153 is positioned over the fibrous polymer 137 the first optic cable 131 such that a conical opening 157 in the outer sleeve 153 encloses a flared end 155 of the internal sleeve 151 . A portion of the fibrous polymer 137 is thus retained between the flared end of the internal sleeve 151 and the conical opening of the outer sleeve 153 . Similarly, another outer sleeve 153 is positioned over the fibrous polymer 147 in the second optic cable 141 such that the conical opening 157 in the other outer sleeve 153 encloses the flared end 155 of the other internal sleeve 151 to retain a portion of the fibrous polymer 147 .
A crimp 159 is formed in one end of the metal tube 150 at the outer sleeve 153 , and another crimp 159 is formed in another end of the metal tube 150 at the other outer sleeve 153 , to secure the metal tube 150 to the first optic cable 131 and to the second optic cable 141 . It can be appreciated by one skilled in the relevant art that a tensile force applied to the first optic cable 131 is thus conveyed through the fibrous polymer 137 and through the metal tube 150 to the fibrous polymer 147 , and thus transferred to the second optic cable 141 without stressing either the first optic fiber 133 or the second optic fiber 143 . This configuration ensures that the first optic fiber 133 remains spliced to the second optic fiber 143 after laying, pulling, or other installation procedures have been performed on the first optic cable 131 and the second optic cable 141 .
The disclosed method of mechanical optic fiber splicing, using the mechanical splices 20 and 140 as examples, can be explained with additional reference to a flow diagram 160 in FIG. 14 . A ferrule (i.e., the ferrule 21 , the ferrule 51 , the ferrule 111 , the ferrule 121 , or another suitably-configured ferrule) is obtained and the optic fibers are prepared by trimming and stripping as required, at step 161 . If the splice to be made is an optic fiber cable mechanical splice, or is a fiber splice that may be subjected to harsh environments, at decision box 163 , internal sleeves 151 and outer sleeves 153 are emplaced as described above to retain the fibrous polymer material, and the metal tube 150 may be placed over one of the optic fibers, in step 165 . If, at decision box 163 , the splice to be made is for loose-tube construction optic fibers, the metal tube may not be required and operation proceeds directly to decision box 167 .
If the ferrule has been preloaded with epoxy, at decision box 167 , the optic fibers are inserted into the ferrule, at step 171 . Preferably, the preloaded ferrule has been stored by sealing in a light blocking and moisture blocking packaging to prevent premature curing of the epoxy. If the ferrule has not been preloaded with epoxy, at decision box 167 , a predetermined quantity of epoxy may be injected into the ferrule, at step 169 , and then the optic fibers may be inserted at opposite ends of the ferrule, as in step 171 .
A predetermined compressive axial force is applied to the optic fibers after insertion to minimize the thickness of the layer of epoxy in the region between the fiber ends, at step 173 . Preferably, the magnitude of the force is restrained to prevent possible damage to the optic fibers. This compressive force may be applied and maintained by the spring 69 , shown in FIG. 4 . The epoxy 41 in the ferrule is cured, at step 175 , by irradiation with a predetermined intensity of ultraviolet light for a predetermined time.
If the mechanical splice is to be used in loose-tube construction, rather than in a jacketed fiber cable application, at decision block 177 , the mechanical splice is complete, at step 179 . If, on the other hand, the mechanical splice is to used with jacketed optic fiber cable, the metal tube 150 is positioned to enclose the ferrule and the ends of the metal tube 150 are crimped onto the outer sleeves 153 , in step 181 , each internal sleeve 151 and outer sleeve 153 retaining therebetween a flexible fibrous polymer portion of the corresponding optic fiber cable.
It is to be understood that the description herein is exemplary of the invention only and is intended to provide an overview for the understanding of the nature and character of the invention as it is defined by the claims. The accompanying drawings are included to provide a further understanding of various features and embodiments of the method and apparatus of the invention which, together with their description serve to explain the principles and operation of the invention. Thus, while the invention has been described with reference to particular embodiments, it will be understood that the present invention is by no means limited to the particular constructions and methods herein disclosed and/or shown in the drawings, but also comprises any modifications or equivalents within the scope of the claims.
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A method and apparatus for mechanically splicing a pair of optic fibers or optic cables, the mechanical splice comprising: a ferrule having an axial capillary bore, the capillary bore configured to enclose the optic fibers at both ends of the ferrule; and cured epoxy disposed to secure together the ends of the optic fibers and to secure the optic fibers to an inside surface of the capillary bore, the ferrule optionally enclosed in a metal tube.
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BACKGROUND OF THE INVENTION
This invention deals generally with boats and more specifically with a boat upon which is mounted an elevator device to raise personnel above the boat deck.
Most of us are vaguely aware that highway bridges must be inspected regularly, but few are aware of the procedures involved in such inspections. Since inspection of the underside of such structures is federally mandated, there must be some way to gain access to the structure below the roadway. Most bridge inspections are performed by walking on the ground, from ladders, with conventional bucket trucks, or, for bridges high above rivers, by using articulating cranes with platforms or buckets on them.
The cranes almost always require lane closures on the bridge, although occasionally a shoulder closure will suffice, and often bridges that have been load rated cannot be accessed by cranes because the cranes are too heavy. For such bridges catenary cables with sliding or rolling scaffolds are an alternative. Catenary cables do not generally require lane closures, but their installation is difficult, and often dangerous, work.
There is an alternative for bridges which are not too high above the ground level they cross. That alternative is to use an aerial boom with a bucket and to support it from a vehicle that can traverse the ground below the bridge. One such apparatus is an aerial boom mounted upon a four wheel drive truck, such as a Hummer. Such vehicles are presently being used for some bridge inspections. The limitation of such vehicles is that they can not operate in or cross rivers of any significant depth. In fact, the depth limit is determined by the height of the vehicle engine above the bottom of the wheels, and that is typically only about 2½ feet.
Some use has been made of boats for access to the underside of bridges, but they are makeshift arrangements which are time consuming to set up and limited in height. Typically, they have simply involved conventional scaffolds erected aboard a boat and extending above deck height. Operation of such boat and scaffold systems in tidal areas often requires multiple changes and adjustments in the scaffolding heights during the course of the bridge inspection. Clearly, such scaffolds must be completely disassembled before the boat is moved over a road to a new location.
It would be very beneficial to have available a variable lift device that has the capability of inspecting or maintaining different height bridges above deep water without any use of the bridge roadway itself and without time consuming set up of scaffolds. The versatility of such a unit would be enhanced even further if it could be moved over roads without being disassembled.
SUMMARY OF THE INVENTION
The present invention is an outboard motor propelled catamaran boat with a permanently attached centered elevator lift that can raise personnel as high as 32 feet above the waterline. Although the preferred embodiment of the boat itself is narrow enough to be transported over roads on a trailer, partially water-filled outrigger pontoons increase the beam to a width sufficient to stabilize the boat when the lift is fully raised. The outrigger pontoons are mounted on pivoting arms so that they can be pivoted back aboard the boat for transport, and when the outrigger pontoons are aboard and resting on their supports above the deck, they are well below the height of the lowered elevator lift. The typical road height of the boat on its trailer is therefore only 13 feet.
The preferred embodiment of the invention uses two outrigger pontoons extending off only one side of the boat. This configuration yields a valuable benefit for bridge maintenance. It permits one side of the boat to be moved close up against bridge supports, and since the personnel platform atop the elevator lift is essentially the same width as the boat, personnel can easily inspect or work on the bridge support to which they are adjacent.
The invention therefore furnishes simple access to bridges above deep water, but is easily transported to locations where bridge work is required. Furthermore, the relatively small size of the boat permits it to be launched at conventional boat ramps after which it can move under its own power to the bridge location.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the preferred embodiment of the invention with the outrigger pontoons extended and the scissors elevator lift extended.
FIG. 2 is a view of the preferred embodiment of the invention loaded upon a trailer with the outrigger pontoons loaded aboard and the elevator lift lowered.
FIG. 3 is a side view of an alternate embodiment of the invention that uses an aerial boom to lift personnel into position.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows lift boat 10 of the present invention that is catamaran boat 12 with hull 13 propelled by outboard motors 14 . Boat 12 has a permanently attached scissors elevator lift 16 that can raise personnel as high as 32 feet above the water. Although the preferred embodiment of boat 12 itself is only 8 feet wide, and therefore narrow enough to be transported over roads on a trailer, partially water-filled outrigger pontoons 18 increase the beam to a 14 feet width and stabilize boat 12 when elevator lift 16 is raised. Pontoons 18 are mounted on pivoting arms 20 which are also attached to and pivot on deck 24 . Pontoons 18 can therefore pivot back aboard the boat for storage and transport. However, when pontoons 18 are deployed in the water they are fixed in place by adjustable length, removable, rigid struts 21 that are attached to pontoons 18 and to fixed points on pontoon supports 22 that are attached to deck 24 . When pontoons 18 are aboard boat 12 and resting on pontoon supports 22 above deck 24 , they are below the 6 foot 4 inch height of lowered elevator lift 16 . The typical road height of the boat on its trailer is therefore only 13 feet. Boat 12 used in the preferred embodiment is 30 feet long, and pontoons 18 are 24 inches wide at the waterline.
For safety purposes, barrier 26 is installed around deck 24 , and railings 28 surround elevator platform 30 . The operation of elevator lift 16 is controlled from elevator platform 30 by the use of control box 32 , and control cables 34 extend down from elevator platform 30 to elevator lift base 36 which includes a battery power source (not shown). Scissors elevator lift 16 is a conventional unit Upright Model 31 N made by the Upright Company. It is built for normal use on land and usually is supported by four wheels. However, for use in this application, the wheels are removed and the axles are mounted through plates 38 that are attached to deck 24 . At full elevation, elevator lift 16 places elevator platform 30 at 32 feet above water level, which yields a working inspection height of 38 feet above the water.
FIG. 2 is a view of boat 12 of the preferred embodiment of the invention loaded upon trailer 40 with outrigger pontoons 18 loaded aboard and scissors elevator lift 16 fully lowered. As can be appreciated from FIG. 2, with pontoons 18 stowed aboard and elevator lift 16 lowered, the clearance height of the entire structure is suitable for road travel. To facilitate this, boat anchor 42 is also stowed aboard, and boat 12 is tied down on conventional trailer 40 with conventional tie down straps 44 .
Some other aspects of the invention can also be seen in FIG. 2 . Valved pipes 46 are used to supply and remove water ballast from outrigger pontoons 18 . Pontoons 18 are chambered so that when the pontoons are deployed in the water, the bottom chambers, which occupy about one-third the total volume, are filled with water while the balance of the volume is kept full of air for flotation. Each of the two pontoons is 2 feet in diameter and 9 feet, 4 inches long, and when they are deployed they are half submerged. The pontoons are an important factor in the stability of boat 12 when elevator lift 16 is at full height. The water is drained out as the pontoons are pivoted aboard the boat in order to reduce the trailer load. They are pivoted aboard with the aid of cables and winches (see FIG. 3 ). The total weight of boat 12 before mounting on trailer 40 is approximately 12,600 pounds.
FIG. 3 is a side view of an alternate embodiment of the invention in which boat 50 has aerial boom 52 installed on deck 24 to lift personnel into position for bridge maintenance.
As with the preferred embodiment shown in FIG. 1 and FIG. 2, boat 50 is propelled by outboard motors 14 and is stabilized by pontoons 18 . Pontoons 18 are locked into their deployed position by adjustable length, rigid struts 21 . The lengths of struts 21 , are adjusted by the use of turnbuckles 23 (see FIGS. 1 and 3 ). These lengths are adjusted for various heights and orientations of the elevator devices.
When pontoons 18 are stowed aboard boat 50 they are held against pontoon supports 22 . Winches 54 and cables 56 , which are not seen in FIG. 1 or FIG. 2, are attached to pontoons 18 and are used to lift pontoons 18 aboard boat 50 for loading onto a trailer for road transport.
The significant difference between the preferred embodiment of FIGS. 1 and 2 and the alternate embodiment of FIG. 3 is the elevator device used to lift personnel into their bridge inspection and maintenance positions. In the alternate embodiment of FIG. 3 conventional aerial boom 52 is used as the elevator device.
Aerial boom 52 is mounted above deck 24 and supported by pillar 58 . Aerial boom 52 is a conventional assembly and includes gears and hydraulic motors so that it can rotate 360 degrees in the horizontal plane. Conventional elbow structure 60 of aerial boom 52 permits bucket 42 to be lowered and retracted or raised and extended. The position of bucket 62 shown in FIG. 3 is an intermediate one, and bucket 62 can be raised and extended significantly more.
In the embodiment of boat 50 shown in FIG. 3, aerial boom 52 is a Versalift Model SST37EIH made by Time Manufacturing Co. of Waco, Tex. It has a bucket capacity of 400 pounds, and the bottom of bucket 42 has a maximum height (above deck 24 ) of 36.7 feet.
The present invention thereby provides an apparatus which fills a vital need. It can reduce the time and cost of inspecting bridges above deep water, but most important, it can permit such inspections without any effect whatsoever on the traffic over the bridge. Furthermore, with the pontoons stored aboard the boat, the personnel elevator apparatus fully lowered, and the boat loaded onto a trailer, the width and height of the combined boat and trailer are below legal road limits so that the trailer with the boat aboard can legally move over roads without special permits.
It is to be understood that the form of this invention as shown is merely a preferred embodiment. Various changes may be made in the function and arrangement of parts; equivalent means may be substituted for those illustrated and described; and certain features may be used independently from others without departing from the spirit and scope of the invention as defined in the following claims.
For example, different size boats and lift devices of different design can be used. Moreover, fewer or more pontoons installed on one or both sides of the boat can be used, and different shaped hulls and different propulsion devices are possible. Furthermore, the invention can, of course, be used for purposes other than inspection of bridges.
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The apparatus is a boat with a device for lifting a worker up to a location under bridges for maintenance or inspection. The preferred embodiment of the invention is an outboard motor propelled catamaran with a scissors type lift elevator or aerial boom located approximately in the center of the boat. One or more outrigger pontoons that are partially filled with water stabilize the boat, and the pontoons are pivoted back aboard the boat and emptied for over the road transport of the boat.
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This application claims benefit of U.S. Ser. No. 10/906,303, filed Feb. 14, 2005, Continuation-In-Part application of International Application No. PCT/US04/43465, filed Dec. 23, 2004, which is a Continuation-In-Part application of Int'l App'l No. PCT/US04/33359, filed Oct. 8, 2004, which claims benefit of U.S. Ser. Nos. 60/532,101, filed Dec. 23, 2003, and 60/509,851, filed Oct. 9, 2003; and which claims benefit of U.S. Ser. Nos. 60/617,379, filed Oct. 8, 2004, 60/613,811, filed Sep. 27, 2004, and 60/607,858, filed Sep. 7, 2004. The contents of these preceding applications are hereby incorporated in their entireties by reference into this application.
Throughout this application, various publications are referenced. Disclosures of these publications in their entireties are hereby incorporated by reference into this application in order to more fully describe the state of the art to which this invention pertains.
FIELD OF THE INVENTION
This invention relates to extracts from a plant called Wenguanguo or Xanthoceras sorbifolia , their uses and functions, and methods of their preparation. This invention further relates to novel compounds obtainable from Xanthoceras sorbifolia and plants from the sapindaceae family.
BACKGROUND OF THE INVENTION
Wenguanguo is a species of the sapindaceae family. Its scientific name is Xanthoceras sorbifolia Bunge. Wenguanguo is the common Chinese name. Others are Wenguannguo, Wenguanmu, Wenguanhua, Xilacedeng, Goldenhorn and Yellowhorn. Wenguanguo is grown in Liaoning, Jilin, Hebei, Shandong, Jiangsu, Henan, Shanxi, Shaanxi, Gansu, Ningxia and Inner Mongolia, China. Its seeds, leaves and flowers are edible and have been used as a folk or traditional medicine to treat enuresis for centuries. Its branches and woods are also used as a folk or traditional medicine. For more detailed information and background or relevent art of the present invention, please refer to page 1, lines 25-38, to page 13 of International PCT Application No. PCT/US04/33359, filed Oct. 8, 2004, and U.S. Ser. No. 10/906,303, filed Feb. 14, 2005. The contents of these preceding applications are hereby incorporated in their entireties by reference into this application.
Yingjie Chen, Tadahiro Takeda and Yukio Ogihara reported in Chem. Pharm. Bull 33(4)1387-1394(1985) described a study on the constituent of Xanthoceras sorbifolia Bunge. See Section V. Saponins from the Fruits of Xanthoceras sorbifolia . Four new saponins were isolated from the fruits of Xanthoceras sorbifolia Bunge. The structures of these saponins are bunkankasaponins A, B, C and D. The chemical name of these compounds are:
22-O-acetyl-21-O-(4-O-acetyl-3-O-angeloyl)-β-D-fucopyranosyl-3-O-[β-D-glucopyranosyl-(1→2)-β-D-glucuronopyranosyl]protoaecigenin 22-O-acetyl-21-O-(3,4-di-O-angeloyl)-β-D-fucopyranosyl-3-O-[β-D-glucopyranosyl-(1→2)-β-D-glucuronopyranosyl]protoaecigenin 28-O-acetyl-21-O-(4-O-acetyl-3-O-angeloyl)-β-D-fucopyranosyl-3-O-[β-D-glucopyranosyl-(1→2)-β-D-glucuronopyranosyl]protoaecigenin 28-O-acetyl-21-O-(3,4-di-O-angeloyl)-β-D-fucopyranosyl-3-O-[β-D-glucopyranosyl-(1→2)-β-D-glucuronopyranosyl]protoaecigenin.
The functions of these compounds were not previously disclosed.
Yingjie Chen, Tadahiro Takeda and Yukio Ogihara reported in Chem. Pharm. Bull 33(3)1043-1048(1985) described studies on the constituent of Xanthoceras sorbifolia Bunge. See Section IV. Structures of the Miner Prosapogenin. The prosapogenins from the partial hydrolyzate of fruit saponin of Xanthoceras sorbifolia were examined, and are characterized as:
16-O-acetyl-21-O-(3,4-di-O-angeloyl-β-D-fucopyranosyl)protoaecigenin 22-O-acetyl-21-O-(3,4-di-O-angeloyl-β-D-fucopyranosyl)protoaecigenin 3-O-β-D-glucuronopyranoside.
The functions of these compounds were not previously disclosed.
Yingjie Chen, Tadahiro Takeda and Yukio Ogihara. Chem. Pharm. Bull 33(1)127-134(1985) described studies on the constituent of Xanthoceras sorbifolia Bunge. See Section III. Minor Prosapogenins aponins from the Fruits of Xanthoceras sorbifolia Bunge. The structure of 3 minor prosapogenins, obtained by acid hydrolysis of the crude saponin faction, were characterized as:
21-O-(3,4-di-O-angeloyl)-β-D-fucopyranosyltheasapogenol B 21-O-(4-O-acetyl-3-O-angeloyl)-β-D-fucopyranosyltheasapogenol B 21-O-(4-O-acetyl-3-O-angeloyl)-β-D-fucopyranosyl-22-O-acetylprotoaescigenin.
The functions of these compounds were not previously disclosed.
Yingjie Chen, Tadahiro Takeda and Yukio Ogihara in Chem. Pharm. Bull 33(4)1387-1394(1985) described a study on the constituent of Xanthoceras sorbifolia Bunge. See Section II. Major Sapogenol and prosapogenin from the Fruits of Xanthoceras sorbifolia . In addition to above studies, saponins with angeloyl groups attached were also reported in the following reports.
Laurence Voutquenne, Cecile Kokougan. Catherine Lavaud, Isabelle Pouny, Marc Litaudon. “Triterpenoid saponins and Acylated prosapogenins from Harpullia austro-calcdonica.” Phytochemistry 59 (2002) 825-832.
Zhong Jaing, Jean-francois Gallard, Marie-Therese Adeline, Vincent Dumontet, Mai Van Tri, Thierry Sevenet, and Mary Pais “Six Triterpennoid Saponins from Maesa laxiflora.” J. Nat. Prod. (1999), 62, 873-876.
Young Seo, John M. Berger, Jennine Hoch, Kim M Neddermann, Isia Bursuker, Steven W. Mamber and David G. Kingston. “A new Triterpene Saponin from Pittosporum viridiflorum from the Madagascar Rainforest”. J. Nat. Prod. 2002, 65, 65-68.
Xiu-Wei Yang, Jing Zhao, Xue-Hui Lui, Chao-Mei Ma, Masao Hattori, and Li He Zhang “Anti-HIV-1 Protease Triterpenoid Saponins from the Seeds of Aesculus chinensis .” J. Nat. Prod. (1999), 62, 1510-1513.
Yi Lu, Tatsuya Umeda, Akihito Yagi, Kanzo Sakata, Tirthankar Chaudhuri, D.K. Ganguly, Secion Sarma. “Triterpenoid Saponins from the roots of the tea plant ( Camellia sinensis var. Assamica ).” Phytochchemistry 53 (2000) 941-946.
Sandra Apers, Tess E. De Bruyne, Magda Claeys, Arnold J. Viletinck, Luc A.C. Pieters. “New acylated triterpenoid saponins from Maesa laceceolata.” Phytochemistry 52 (1999) 1121-1131.
Ilaria D'Acquarica, Maria Cristina, Di Giovanni, Francesco Gasparrini, Domenico Misiti, Claudio D'Arrigo, Nicolina Fagnano, Decimo Guarnieri, Giovanni Iacono, Giuseppe Bifulco and Raffaele Riccio. “Isolation and structure elucidation of four new triterpenoid estersaponins from fruits of the Pittosporumtobira AIT.” Tetrahedron 58 (2002) 10127-10136.
Cancer cells are defined by two heritable properties: (1) they reproduce in defiance of normal restraints on cell division; and (2) they invade and colonize territories normally reserved for other cells.
Cancers require mutations of one to many genes for its development, and they are classified according to the tissue and cell type from which they arise. Cancers arising from epithelial cells are named carcinomas; those arising from connective tissue or muscle cells are named sarcomas. In addition, there are cancers called leukemias, which are derived from hemopaietic cells. Cancers can also develop from cells of the nervous system.
Cancers originating from different types of cells are, in general, very different diseases. Each cancer has characteristics that reflect its origin. Even when a cancer has metastasized and proliferated out of control, its origins can be traced back to a single, primary tumor. Therefore, it is important to develop drugs or compounds capable of targeting various types of cancer cells.
Ovarian cancer is the 5th leading cause of cancer death in women and the leading cause of death from gynecologic malignancies. In the United States, females have a 1.4 to 2.5%, or 1 out of 40-60 women, lifelong chance of developing ovarian cancer. Older women are at highest risk. More than half of the deaths from ovarian cancer occur in women between 55 and 74 years of age, and approximately one quarter of ovarian cancer deaths occur in women between 35 and 54 years of age. See MedlinePlus Encyclopedia on ovarian cancer at http://www.nlm.nih.gov/medlineplus/ency/article/000889.htm.
Ovarian cancer is disproportionately deadly for a number of reasons. First, symptoms are vague and non-specific, so women and their physicians frequently attribute them to more common conditions. By the time the cancer is diagnosed, the tumor has often spread beyond the ovaries. Also, ovarian cancers shed malignant cells that frequently implant on the uterus, bladder, bowel, and lining of the bowel wall (omentum). These cells can begin forming new tumor growths before cancer is even suspected. Second, because no cost-effective screening test for ovarian cancer exists, more than 50 percent of women with ovarian cancer are diagnosed in the advanced stages of the disease.
This invention provides compounds or compositions extracted from Xanthoceras sorbifolia or plants from the sapindaceae family, or synthesized which have substantial potency against ovarian cancer.
SUMMARY OF THE INVENTION
In accordance with these and other objects of the invention, a brief summary of the present invention is presented. Some simplifications and omission may be made in the following summary, which is intended to highlight and introduce some aspects of the present invention, but not to limit its scope. Detailed descriptions of a preferred exemplary embodiment adequate to allow those of ordinary skill in the art to make and use the invention concepts will follow in later sections.
The invention provides six novel compounds of structure (Y1, Y2, Y or Y3, Y8, Y9, Y10) as shown in FIG. 1 . As used herein, “Y” is also referred to as “Y3”.
The formula, chemical name and common name of these compounds are presented in Table 1 below.
TABLE 1
Formula, Chemical Name and Common Name Six Novel Compounds of
structure (Y, Y 1 , Y 2 , Y8, Y9, Y10)
Names
Formula
Chemical Name
Y (Y3)
C 57 H 88 O 23
3-O-[β-D-galactopyranosyl(1→2)]-α-L-arabinofuranosyl(1→3)-β-D-
glucuronopyranosyl-21,22-O-diangeloyl-3β,15α,16α,21β,22α,28-
hexahydroxyolean-12-ene,
Y1
C 65 H 100 O 27
3-O-[β-D-galactopyranosyl(1→2)]-α-L-arabinofuranosyl(1→3)-β-D-
glucuronopyranosyl-21-O-(3,4-diangeloyl)-α-L-rhamnophyranosyl-22-O-
acetyl-3β,16α,21β,22α,28-pentahydroxyolean-12-ene
Y2
C 57 H 88 O 24
3-O-[β-D-glucopyranosyl-(1→2)]-α-L-arabinofuranosyl(1→3)-(-D-
glucuronopyranosyl-21,22-O-diangeloyl-3(,15(16(,21(,22(,24(,28-
heptahydroxyolean-12-ene
Y8
C 57 H 87 O 23
3-O-[β-galactopyranosyl(1→2)]-α-arabinofuranosyl(1→3)-β-
glucuronopyranosyl-21,22-O-diangeloyl-3β,16α,21β,22α,28-
pentahydroxyolean-12-ene
Y9
C 63 H 98 O 26
3-O-[β-galactopyranosyl(1→2)]-α-arabinofuranosyl(1→3)-β-
glucuronopyranosyl-21-O-(3,4-diangeloyl)-α-rhamnopyranosyl-3β,16α,
21β,22α,28-pentahydroxyolean-12-ene
Y10
C 57 H 87 O 22
3-O-[β-galactopyranosyl(1→2)]-α-arabinofuranosyl(1→3)-β-
glucuronopyranosyl-21,22-O-diangeloyl-3β,16α,21β,22α,28-
pentahydroxyolean-12-ene
The above six compounds (Y, Y1, Y2, Y8, Y9 and Y10) have anti-cancer effect. These compouns inhibit the growth of human ovarian and other cancer cells. See FIGS. 2 , 3 and 4 .
A concensus sub-structure is identified from these active compounds (Y, Y1, Y2, Y8, Y9 and Y10). The concensus sub-structure of these compounds is the biangeloyl groups located on adjacent carbons.
For Y, Y2, Y8 and Y10, the biangeloyl are located at 21β and 22α of the triterpene backbone. See FIG. 5 .
For Y1 and Y9, the biangeloyl are located at C3 and C4 of the sugar ring. See FIG. 6 . Accordingly, the biangeloyl groups of these active compounds (Y, Y1, Y2, Y8, Y9 and Y10) are situated in trans-position in respect to each other on a planar structure. See FIG. 7 .
Studies of the structure and function relationship of these six structures indicate that changes of the functional groups at C15 and C24 of the triterpene do not affect anticancer activity.
These compounds (Y, Y1, Y2, Y8, Y9 and Y10) are active for inhibition of tumor growth. See FIGS. 2 , 3 and 4 . These compounds are purified by methods of chromatograpy involving FPLC and HPLC as described in FIGS. 8 , 9 , 10 , 11 , 12 and 13 .
The compound Y is purified, as shown in FIG. 11A , with procedure described in this application. The purified compound Y shows potence (IC50=1.5 ug/ml) 10 times higher than the original extract (IC50=25 ug/ml) by comparing FIG. 2 with FIG. 14 . Compound Y has a high selectivity toward ovarian cancer. See FIG. 15 .
The purified compound Y1, Y2, Y8, Y9, and Y10 also show inhibitory activity toward human cancer cells with a higher potency toward ovarian carcinoma. See FIGS. 3 and 4 .
The plant extract containing compound Ys shows inhibitory activity toward the following human cancer cells, i.e., eleven human cancer cell lines were tested in this study, with a higher potency toward ovarian carcinoma. See comparison of activities among these cells in FIGS. 14 , 15 and 16 and Table 3.1. As used herein, Ys or compound Ys is used to denote compound Y or Y3, Y1, Y2, Y8, Y9, Y10 or other compounds obtainable from Xanthoceras sorbifolia extract.
This invention provides an extract of Xanthoceras sorbifolia capable of inhibiting cancer growth. The cancer includes, but is not limited to ovary cancer, bladder cancer, prostate cancer, leukocytes cancer, and bone cancer.
The compounds can be isolated from the plant called Xanthoceras sorbifolia or can be synthesized chemically, or extracted from other biological sources.
This invention provides a process of producing active compounds from husks, leaves, branches or stems, and fruit-stems, roots and barks of the Wenguanguo and can be employed separately or be combined. This invention further discloses methods of their preparations.
In addition to saponin, the extracts contain saccharides, proteins, glycosides, flavonoids, curmarin extracts, alkaloid extracts, organic acid extracts, tannin and others. In this application saponins were investigated and have been shown to possess inhibitory activity against cancer growth.
The compounds or compositions of the present invention may regulate many cellular pathways including the receptors or components of a cell such as G-protein receptor, Fas protein, receptor Tyrosine Kinases, Mitogen, mitogen receptor. The compounds can be isolated from the plant called Xanthoceras sorbifolia or can be synthesized chemically, or extracted from other biological sources.
This invention provides compounds, including compound of structures Y, Y1, Y2, Y8, Y9 and Y10, obtainable from Xanthoceras sorbifolia and capable of inhibiting cancer growth. In an embodiment, the cancer includes, but is not limited to bladder cancer, cervix cancer, prostate cancer, lung cancer, breast cancer, leukocytes cancer, colon cancer, liver cancer, bone cancer, brain cancer, and ovary cancer.
This invention provides a compound of oleanene triterpenoidal saponin comprising a side chain at Carbon 21 and Carbon 22 of said compound, wherein the side chain comprises angeloyl groups. In an embodiment, the compound comprises one or more sugars, wherein C3 and C4 of the sugar are acylated with angeloyl groups.
This invention provides a triterpinoidal saponin compound comprising a triterpene backbone and biangeloyl groups, wherein the biangeloyl groups are attached to 21β and 22α of the triterpene backbone, wherein the presence of the biangeloyl group produces anticancer activity.
This invention provides a triterpenoidal saponin compound comprising a triterpene backbone and a sugar moiety or sugar chain, wherein the sugar moiety or sugar chain is attached to the triterpene backbone, wherein the sugar moiety or sugar chain further comprises a biangeloyl group, and wherein the presence of the biangeloyl group produces anticancer activity.
This invention provides a triterpenoidal saponin compound comprising a triterpene backbone, said triterpene backbone is acylated at either 21β or 22α position or at both 21β and 22α position with a sugar moiety or sugar chain, wherein at least one sugar in the sugar moiety or sugar chain comprises angeloyl groups attached to the C3 and C4 position of said sugar.
As used herein, moiety means one of two or more parts into which something may be divided, such as the various parts of a molecule.
In an embodiment, the biangeloyl groups are in the trans-position on a planar structure, and the presence of the biangeloyl group produces anticancer activity.
This invention provides a salt of the above-described compounds.
This invention provides a pharmaceutical composition comprising an effective amount of the above-described compounds and a pharmaceutically acceptable carrier(s).
This invention provides a method for isolating compounds from Xanthoceras sorbifolia comprising the steps of: extracting Xanthoceras sorbifolia powder with an appropriate amount of an organic solvent for an appropriate amount of time to obtain an extract, identifying the bioactive components in the extract; purifying the bioactive components in the extract with FPLC to obtain a fraction of the bioactive component; and isolating the pure bioactive component with preparative HPLC.
This invention provides a compound having a structure verified by NMR spectral data derived from proton NMR, carbon NMR, 2D NMR of the Heteronuclear Multiple Quantum Correlation (HMQC), Heteronuclear Multiple Bond Correlation (HMBC), NOESY and COSY, and Mass spectral data derived from MALDI-TOF and ESI-MS.
This invention provides the chemical features of a compound and its derivatives which are effective against cancer. Due to complexity of nature, the compounds or compositions of the present invention regulate various cellular pathways including but not limiting the followings: the receptors or components such as G-protein receptor, Fas protein, receptor for Tyrosine Kinases, mitogens, or mitogen receptors. TGF Beta-smad, FGF, TGF-beta and TGF-alpha, ras-GTPase-MAP kinase, jun-fos, Src-fyn, Jak-Jnk-STAT, BMP, Wnt, myc-cell proliferation, etc. The Xanthoceras Sorbifolia derived compound and/or composition may regulate the components and receptors and re-activates the cell death program.
DETAILED DESCRIPTION OF THE FIGURES
FIG. 1 shows the structures of six active anticancer saponins isolated from Xanthoceras Sorbifolia extract.
FIG. 2 shows the anticancer activity of purified Compound Y. The experiment was performed on ovarian cancer cells (OCAR-3) and the inhibition activity was determined by MTT assay. For details, refer to Experiment 3. Abscissa: Concentration (ug/ml). Ordinate: % Cell Growth. The IC50 is approximately 1-1.5 ug/ml. A: Point scale. B: Linear scale.
FIG. 3 shows the inhibition of the purified Compound Y1 and Compound Y2 on ovarian cancer cells' growth.
FIG. 4 shows the anticancer activity of Y, Y8, Y9 and Y10 with ovarian cancer cells determined by MTT assay.
FIG. 5 shows the consensus structure derived from four active anticancer saponins (Y, Y2, Y8 and Y10).
FIG. 6 shows the consensus structure derived from two active anticancer saponins (Y1 and Y9).
FIG. 7 shows a general structural formula derived from the consensus structures of the six active compounds (Y, Y1, Y2, Y8, Y9 and Y10). (A) A consensus active functional group is the biangeloyl group attached to 21β and 22α of the triterpene backbone. (B) A consensus active functional group is the biangeloyl group attached at C3 and C4 of a sugar ring (or rhamnose). In both cases, the functional active structure is a biangeloyl group situated in trans-position on a planar structure.
FIG. 8 shows the separation of the components of Xanthoceras sorbifolia extract by HPLC with a μbondapak C18 column. Details of experiment were presented in Experiment 2.
FIG. 9 shows the elution profile of an extract of Xanthoceras sorbifolia in FPLC with 10-80% gradient. Ordinate: Optical density (at 245 nm). Abscissa: Fractions (5 ml/fraction).
FIG. 10 shows the results of the screening of cell growth activity of fractions obtained from FPLC chromatography. The assay was conducted in bladder cells. The fractions obtained from FPLC as shown in FIG. 9 were used. As shown in this figure, different components of Xanthoceras sorbifolia extracts cause either growth or inhibition effects on cells. Only fraction 5962 (Fraction Y) causes cell inhibition. Fractions 610, 1116 and 1724 cause minor stimulation of cell growth. Abscissa: concentration (ug/ml). Ordinate: % Cell Growth (determined by MTT assay).
FIG. 11 shows HPLC profile of Fraction Y with 45% acetonitrile isocratic elution in a preparative C18 column (Delta Pak C18). Under these conditions, fractions Y (Y3), Y1 and Y2 are well separated from each other and they are subsequently purified. A and B shows the purity of the collected Y3 and Y2 by HPLC under same conditions.
FIG. 12 shows the separation profile of Y8-Y10 with 45% acetonitrile isocratic elution in a preparative C18 column (Delta Pak C18).
FIG. 13 shows the HPLC profiles of purified Y8, Y9 and Y10.
FIG. 14 shows the growth curves of ovarian cancer cells after treatment with the crude extract of Xanthoceras sorbifolia as determined by the MTT assay. This study determined the sensitivity of the extract of Xanthoceras sorbifolia on cancer cells. In these experiments, cancer cell lines from 11 different human organs were employed. This figure shows that ovary cancer cells are the most sensitive cancer cells in responding to Xanthoceras Sorbifolia . Results of other cancer cells were represented in FIGS. 16A-D . Abscissa: concentration (ug/ml). Ordinate: % Cell Growth (determined by MTT assay).
FIG. 15 shows the comparison of potency of Compound Y between ovarian cancer cells and cervical cancer cells. Ovarian cancer cells are much more sensitive than the cervical cancer cells. The IC50 for Compound Y in ovary cells is about 1.5 ug/ml while the IC50 in cervical cancer cells is over 20 ug/ml. See also FIG. 16D . This result confirms that the activity of Compound Y is selective toward ovary cancer.
FIGS. 16A-D show the growth curves of cancer cells derived from different human organs as determined by MTT assay. After treatment with the extract of Xanthoceras Sorbifolia , growth curves of different cell lines were presented and their sensitivities (IC50 values) were determined. Sensitivity of cells toward extract can be divided into 4 groups. (1) Most sensitive: ovary cells (presented in FIGS. 14 and 15 ). (2): Sensitive: bladder and bone (presented in A). (3) Semi-sensitive: leukocyte and liver (presented in B); prostate, breast and brain (presented in C). (4) Least sensitive: colon, cervix and lung (presented in D). Abscissa: concentration (ug/ml). Ordinate: % Cell Growth (determined by MTT assay).
FIG. 17 shows the structure Compound Y with the formula of C 57 H 88 O 23 and the chemical name of 3-O-[β-D-galactopyranosyl(1→2)]-α-L-arabinofuranosyl(1→3)-β-D-glucuronopyranosyl-21,22-O-diangeloyl-3β, 15α, 16α, 21β, 22α, 28-hexahydroxyolean-12-ene.
FIG. 18 shows the sprectrum of proton NMR of Compound Y.
FIG. 19 shows 2D NMR (HMQC) results of Compound Y.
FIG. 20 shows 2D NMR (HMBC) results of Compound Y.
FIG. 21 shows the Mass spectrum of compound Y with MALDI-TOF (high mass): Y+Matrix (CHCA)+Angiotensin 1 “two point calibration”.
FIG. 22 shows the Mass spectrum of compound Y with ESI-MS.
FIG. 23 shows the structure of Compound Y1 with the formula of C 65 H 100 O 27 and the chemical name of 3-O-[β-D-galactopyranosyl(1→2)]-α-L-arabinofuranosyl(1→3)-β-D-glucuronopyranosyl-21-O-(3,4-diangeloyl)-α-L-rhamnophyranosyl-22-O-acetyl-3β, 16α, 21β, 22α, 28-pentahydroxyolean-12-ene.
FIG. 24 shows the Proton NMR spectrum of Compound Y1.
FIG. 25 shows the 2D NMR (HMQC) results of Compound Y1.
FIG. 26 shows the 2D NMR (HMBC) results of Compound Y1.
FIG. 27 shows COSY-NMR profile of Compound Y1.
FIG. 28 shows the chemical structure and the chemical name of Compound Y2.
FIG. 29 shows the proton NMR spectrum of Y2.
FIG. 30 shows the 2D NMR spectrum of Y2 (HMQC)-level-1.
FIG. 31 shows the C13 NMR spectra of compound Y2.
FIG. 32 shows the 2D NMR (HMBC)-level-1 spectra of compound Y2.
FIG. 33 shows the 2D NMR HOHAHA (TOCSY)-level-1 spectrum of compound Y2.
FIG. 34 shows the Mass spectrum of compound Y2+Matrix+Standards.
FIG. 35 shows the chemical structure of Y8.
FIG. 36 shows H-NMR spectrum of Y8.
FIG. 37 shows 2D NMR HMQC (level 1) spectrum of Y8.
FIG. 38 shows 2D NMR HMQC (level 2) spectrum of Y8.
FIG. 39 shows the chemical structure of Y9.
FIG. 40 shows H-NMR spectrum of Y9.
FIG. 41 shows 2D NMR HMQC (level 1) spectrum of Y9.
FIG. 42 shows 2D NMR HMQC (level 2) spectrum of Y9.
FIG. 43 shows the chemical structure of Y10.
FIG. 44 shows H-NMR spectrum of Y10.
FIG. 45 shows 2D NMR HMQC (level 1) spectrum of Y10.
FIG. 46 shows 2D NMR HMQC (level 2) spectrum of Y10.
FIG. 47 shows the chemical structure and the chemical name of Compound R1.
FIG. 48 shows the Proton-NMR spectrum of compound R1.
FIG. 49 shows the 2D NMR (HMQC) spectrum of compound R1.
FIG. 50 shows the 2D NMR (HMBC) spectrum of compound R1.
FIG. 51 shows the 2D NMR (COSY) spectrum of compound R1.
FIG. 52 shows the C13 NMR spectrum of compound R1.
FIG. 53 shows the chemical structure of Compound O54.
FIG. 54 shows the Proton-N MR spectra of compound O54.
FIG. 55 shows the 2D NMR (HMQC) spectra of compound O54.
FIG. 56 shows the 2D NMR (HMBC) spectra of compound O54.
FIG. 57 shows the absorption spectrum of Xanthoceras sorbifolia extract. Abscissa: Wavelength in nm. Ordinate: Optical Density. The extract has three absorption maximum at 207 nm, 278 nm and 500 nm.
FIG. 58 shows the proton NMR spectrum of Y4.
FIG. 59 shows the 2D NMR (HMQC) spectrum of Y4.
FIG. 60 shows purification of component-R with HPLC. A: Extract from fraction #10 of FPLC (iso-30) was further separated by HPLC. B: Rechromatogram of the major component under same condition as described in A.
FIG. 61 . Fractionation of Fraction-O with HPLC with 20% acetonitrile isocratic elution (iso-20).
FIG. 62 . Rechromatography of O28 and O34 (from iso-20).
FIG. 63 . Rechromatography of O54 (from iso-20).
DETAILED DESCRIPTION OF THE INVENTION
This invention provides a compound selected from a compound of formula (1):
or a salt, ester or derivative thereof, wherein: R1 represents angeloyl group; R2 represents angeloyl group; R3 represents OH or H; R4 represents CH3 or CH2OH; and R5 represents D-glucose or D-Galactose.
This invention provides a compound selected from a compound of formula (2):
or a salt, ester or derivative thereof, wherein: R1 represents angeloyl group; R2 represents angeloyl group; and R3 represents Ac or H.
This invention provides a compound selected from a compound of formula (3):
or a salt, ester or derivative thereof, wherein: R1 represents angeloyl group; R2 represents angeloyl group; R3 represents OH or H; R4 represents CH3 or CH2OH; and R5 represents sugar moiety or sugar chain selected from the group consisting of: D-glucose, D-galactose, L-rhamose, L-arabinose, D-xylose, alduronic acid, D-glucuronic acid and D-galacturonic acid.
This invention provides a compound selected from a compound of formula (4):
or a salt, ester or derivative thereof,
wherein:
R1 represent angeloyl group; R2 represent angeloyl group; R3 represents Ac or H; R4 represents H or OH; and R5 represents sugar moiety or sugar chain selected from the group consisting of: D-glucose, D-galactose, L-rhamnose, L-arabinose, D-xylose, alduronic acid, D-glucuronic acid and D-galacturonic acid.
In an embodiment, the angeloyl groups are in the trans-position on a planar structure.
This invention provides a compound comprising the following structure:
This invention provides a composition for inhibiting tumor cell growth, comprising the above-described compounds. In an embodiment, the composition comprises a suitable carrier. In another embodiment, the composition comprises a pharmaceutically suitable carrier.
This invention provides a method for treating ovarian cancer in a subject, comprising administering to said subject an effective amount of the above-described compositions.
A method for isolating compounds from Xanthoceras sorbifolia herb or plants from the sapindaceae family comprising the steps of: (a) extracting Xanthoceras sorbifolia or plant powder with organic solvents to obtain an organic extract; (b) collecting the organic extract; (c) refluxing the organic extract to obtain a second extract; (d) removing the organic solvent from the second extract; (e) drying and sterilizing the second extract to obtain a crude extract powder; (f) fractionating the crude extract powder into components using HPLC and FPLC chromatography with silica gel, C18 and other equivalent solid phase materials; (g) monitoring absorption wavelength at 207 nm or 254 nm; (h) identifying the bioactive components of the crude extract powder; (i) purifying one or more bioactive components of the crude extract powder with FPLC to obtain one or more fraction of the bioactive component; and (j) isolating the desired fraction of the bioactive component with preparative HPLC.
Compound Y
This invention provides a compound comprising the following structure, i.e., see FIG. 17 , with the formula of C 57 H 88 O 23 and the name of 3-O-[β-D-galactopyranosyl(1→2)]-α-L-arabinofuranosyl(1→3)-β-D-glucuronopyranosyl-21,22-O-diangeloyl-3β, 15α, 16α, 21β, 22α, 28-hexahydroxyolean-12-ene, also known as Xanifolia-Y. This compound was isolated from Xanthoceras sorbifolia .
This compound belongs to an oleanene triterpenoidal saponin with a trisaccharide chain attached at C-3 of the aglycone and two angeloyl groups acylated at C-21 and C-22. This compound has anti-cancer activity.
The assignment of this structure is supported by spectral data, i.e., H-NMR, 2D NMR (HMBC, HMQC), and MS (MALDI-TOF, EMS). Accordingly, this compound has the characteristic property as shown in FIGS. 18-22 or Table 5.1.
Compound Y1
This invention provides another compound comprising the following structure, i.e., see FIG. 23 , with the formula of C 65 H 100 O 27 and the name of 3-O-[β-D-galactopyranosyl(1→2)]-α-L-arabinofuranosyl(1→3)-β-D-glucuronopyranosyl-21-O-(3,4-diangeloyl)-α-L-rhamnophyranosyl-22-O-acetyl-3β, 16α, 21β, 22α, 28-pentahydroxyolean-12-ene, also known as Xanifolia-Y1.
This compound is a bisdesmosidic polyhydroxyoleanene triterpenoidal saponin with a trisaccharide chain at C-3 of the backbone and a monosaccharide moiety at C-21 where two angeloyl groups were acylated at C-3 and C-4 position. This compound has anti-cancer activity.
The assignment of this structure is supported by spectral data, i.e., H-NMR, 2D NMR (HMBC, HMQC, COSY), and MS (MALDI-TOF). Accordingly, this compound has the characteristic property as shown in FIGS. 24-27 .
Compound Y2
This invention provides a third compound comprising the following structure, i.e., see FIG. 28 , with the formula of C 57 H 88 O 24 and chemical name of 3-O-[β-D-glucopyranosyl-(1→2)]-α-L-arabinofuranosyl(1→3)-β-D-glucuronopyranosyl-21,22-O-diangeloyl-3β, 15α, 16α, 21β, 22α, 24β, 28-heptahydroxyolean-12-ene, also known as Y2.
This compound (Y2) belongs to saponins comprising a triterpene, a sugar moiety and angeloyl groups linked to the backbone. The angeloyl groups are linked to the backbone at C21 and C22 positions. This compound has anti-cancer activity.
The assignment of this structure is supported by spectral data, i.e., H-NMR, C-NMR, 2D NMR (HMBC, HMQC, TOCSY), and MS (MALDI-TOF). Accordingly, this compound has the characteristic property as shown in FIGS. 29-34 .
Compound Y8
This invention provides a fourth active compound Y8 and the structure was determined by 1D NMR, 2D NMR, and MS analysis. The compound comprises the following structure, i.e. see FIG. 35 , with the formula of C 57 H 87 O 23 and chemical name of 3-O-[β-glucopyranosyl(1→2)]-α-arabinofuranosyl(1→3)-β-glucuronopyranosyl-21,22-O-diangeloyl-3β, 16α, 21β, 22α, 24β, 28-hexahydroxyolean-12-ene.
The assignment of this structure is supported by spectral data, i.e., H-NMR, C13-NMR and 2D NMR (HMQC). Accordingly, this compound has the characteristic property as shown in FIGS. 36-38 .
Compound Y9
This invention provides a fifth active compound Y9 and the structure was determined by 1D NMR, 2D NMR, and MS analysis. The compound comprises the following structure, i.e., see FIG. 39 , with the formula of C 63 H 98 O 26 and chemical name of 3-O-[β-galactopyranosyl(1→2)]-α-arabinofuranosyl(1→3)-β-glucuronopyranosyl-21-O-(3,4-diangeloyl)-α-rhamnopyranosyl-3β, 16α, 21β, 22α, 28-pentahydroxyolean-12-ene.
The assignment of this structure is supported by spectral data, i.e., H-NMR, 2D NMR (HMQC and HMBC). Accordingly, this compound has the characteristic property as shown in FIGS. 40-42 .
Compound Y10
This invention provides a sixth active compound Y10 and the structure was determined by 1D NMR, 2D NMR and MS analysis. The compound comprises the following structure, i.e., see FIG. 43 , with the formula of C 57 H 87 O 22 and chemical name of 3-O-[β-galactopyranosyl(1→2)]-α-arabinofuranosyl(1→43)-β-glucuronopyranosyl-21,22-O-diangeloyl-3β, 16α, 21β, 22α, 28-pentahydroxyolean-12-ene.
The assignment of this structure is supported by spectral data, i.e., H-NMR, C13-NMR and 2D NMR (HMQC). Accordingly, this compound has the characteristic property as shown in FIGS. 44-46 .
This invention provides a compound comprising a sugar and a triterpene or Sapogenin, wherein the triterpene or sapogenin is acylated at Carbon 21 and 22 with Angeloyl groups. In an embodiment, the compound comprises one or more sugars.
This invention shows that extracts of Xanthoceras sorbifolia have anticancer activity. The experiments for determining the anti-cancer activity employ human cells lines derived from eleven human organs (HTB-9 (bladder), HeLa-S3 (cervix), DU145 (prostate), H460 (lung), MCF-7 (breast), K562 (leukocytes), HCT116 (colon), HepG2 (liver), U2OS (bone), T98G (brain) and OVCAR-3 (ovary)). Among the 11 cell lines studies, their sensitivity toward Xanthoceras sorbifolia extract can be divided into four groups: (A) most sensitive: Ovary, see FIG. 14 ; (B) Sensitive: bladder, bone, (C) Srmi-sensitive: prostate, leukocyte, liver, breast, and brain; and (D) lease sensitive: colon, cervix, and lung. See FIG. 16A-D . Their IC50 values are listed in Table 3.1.
TABLE 3.1
IC50 values of Xanthoceras Sorbifolia Extract Determined
in Different Cancer Cells
IC50 determined by
Cancer cells from different organs
MTT assay (ug/ml)
Ovary (most sensitive)
15-15
Bladder (sensitive)
45-50
Bone
40-55
Prostate (semi-sensitive)
40-50
Leukocyte
45-50
Liver
45-65
Breast
65
Brain
70-85
Colon (least sensitive)
90
Cervix
115
Lung
110
In order to identify the active compounds of Xanthoceras sorbifolia , the extracts from Xanthoceras sorbifolia were separated by chromatography comprising FPLC (Fast Protein Liquid Chromatography) and HPLC (High Preferment Liquid Chromatography). Multiple fractions were obtained by FPLC procedures, i.e., see FIG. 9 and HPLC, i.e., see FIG. 8 . Analysis of the fractions by HPLC shows that the extract comprises 26 identifiable fractions, designated as a to z, which are shown in FIG. 8 .
Anti-cancer activities of these fractions were determined by the MTT assay. FPLC fraction 5962, i.e., see FIG. 10 , which coresponding to fraction Y in HPLC, i.e., see FIG. 8 , has the anti-cancer activity. Fraction 5962 was further separated into 4 components Y1 to Y4, i.e., see FIG. 11 . Fraction 6365 was further seperated into 5-6 components, designated as Y5-Y10. See FIG. 12 . The compounds Y or Y3, Y1 and Y2 show strong anti-tumor activity, i.e., see FIG. 2-3 , and were therefore isolated. Similarly, compounds Y8, Y9 and Y10 also show strong anti-tumor activity, i.e., see FIG. 4 , and were therefore purified. See FIG. 13 .
The structures of these active compounds, i.e., Y, Y1, Y2, Y8, Y9 and Y10 and their uses are the subject of this application.
The inhibition effects of the compounds of the present invention on ovarian cancer cells were evaluated with the MTT assay. Compound Y shows at least 10 times higher potency (IC50=1.5 ug/ml), i.e., see FIG. 2 , than the original crude extract as shown in FIG. 14 (IC50=20 ug/ml).
The selectivity of compound Y toward different cell lines was tested, and it was found that compound Y has a much higher potency toward ovarian cancer cells as compared to the cervical cancer cells. See FIG. 15 .
This invention provides a method for identifying and isolating the active compounds from plants, herbs or plant extracts. In an embodiement, the extracts include extracts of Xanthoceras sorbifolia or of plants from the sapindaceae family.
This invention provides the chemical structures of six active compounds obtainable from Xanthoceras sorbifolia or of plants from the sapindaceae family. The compounds are shown in FIG. 1 .
This invention provides spectral data including H-NMR, C-13-NMR, 2D NMR (HMBC, HMQC, COSY, TOCSY), and MS (MALDI-TOF, ESI-MS) in supporting the assigned structures.
This invention provides a consensus sub-structure or functional group from the active compounds purified from fraction Y. The compounds, such as Y or Y3, Y1, Y2, Y8, Y9 and Y10, obtainable from fraction Y are collectively referred to as “Ys”. The consensus sub-structure or functional group of these compounds is the biangeloyl groups located on adjacent carbons. For example, in compound Y, Y2, Y8 and Y10, the biangeloyl are located at 21β and 22α of the triterpene backbone. See FIG. 5 . In compound Y1 and Y9, the biangeloyl groups are located at C3 and C4 of the sugar ring. See FIG. 6 . Accordingly, the biangeloyl groups of these active compounds are situated in trans-position with respect to each other on a planar structure. See FIG. 7 .
The results of this invention indicate the active functional group of these compounds is a biangeloyl group attached in-trans to adjacent carbons located in a planar structure. See FIG. 7 .
This invention provides a salt of the above-described compounds.
This invention provides a composition comprising the above-described compounds and a suitable carrier.
This invention provides a pharmaceutical composition comprising an effective amount of the above-described compounds and a pharmaceutically acceptable carrier.
This invention provides an anti-ovarian cancer agent or composition comprising the above-described compositions.
This invention provides a composition effective against cancer growth. The cancer includes but is not limited to bladder cancer, bone cancer and ovary cancer.
This invention provides a composition comprising the above-described compounds and their salts, esters, derivatives or metabolites capable of inhibiting tumour growth.
This invention provides a composition comprising the above-described compounds and their salts, esters, derivatives or metabolites capable of inhibiting virus growth and/or activities.
In addition to the compound Ys, other compounds were also purified from fraction R and fraction O of the extract of Xanthoceras sorbifolia , which are designated herein as R1 and O54, respectively. Their structures were determined. Preliminary experiments indicate both R1 and O54 do not have anticancer activity.
Compound R1
The structure of Compound R1 shown below and in FIG. 47 , has a chemical formula of C 65 H 106 O 29 and chemical name of 3-O-[angeloyl-(1→3)-β-D-glucopyranosyl-(1→6)]-β-D-glucopyranosyl-28-O-[α-L-rhamnopyranosyl-(1→2)-β-D-glucopyranosyl-(1→6)-β-D-glucopyranosyl-3β, 21β, 22α, 28-tetrahydroxyolean-12-ene, also known as Xanifolia-R1.
The assignment of this structure is supported by spectral data, i.e., H-NMR, C-13-NMR, 2D NMR (HMBC, HMQC, COSY), and MS (MALDI-TOF, EMS). Accordingly, this compound has the characteristic property as shown in FIGS. 48-52 .
Compound-O54
This invention provides a compound O54 purified from the extract of Xanthoceras sorbifolia . The structure of O54 was determined and has a formula of C 60 H 100 O 28 .
The Structure of Compound O54 is shown below, i.e., see FIG. 53 :
The chemical name of compound-O54 is: 3-O-β-D-glucopyranosyl-(1→6)]-β-D-glucopyranosyl-28-O-[α-L-rhamnopyranosyl-(1→2)-β-D-glucopyranosyl-(1→6)-β-D-glucopyranosyl-3β, 21β, 22α, 28-tetrahydroxyolean-12-ene.
The assignment of this structure is supported by spectral data, i.e., 1H-NMR, 2D NMR (HMBC, HMQC). Accordingly, this compound has the characteristic property as shown in FIGS. 54-56 .
SUMMARY
This invention provides methods for identifying and purifying compounds from the plant extract of Xanthoceras sorbifolia . Six compounds have been identified and purified, and have been shown to have anticancer activity. These compounds are collectively referred to as triterpenoidal saponins. A consensus sub-structure is identified from these active compounds. A consensus sub-structure or active functional groups of these compounds is the biangeloyl groups located on adjacent carbons. The biangeloyl groups are located at 21β and 22α of the triterpene backbone, i.e., see FIG. 5 , or located at C3 and C4 of the sugar ring, i.e., see FIG. 6 . Accordingly, the biangeloyl groups of these active compounds are situated in trans-position in respect to each other on a planar structure. See FIG. 7 . The structures or derivatives of the compounds of the present invention are also obtainable by chemical systhesis or from biological sources.
This invention will be better understood from examples which follow. However, one skilled in the art will readily appreciate that the specific methods and results discussed are merely illustrative of the invention as described more fully in the claims which follow thereafter.
EXPERIMENTAL DETAILS
Experiment 1
Herb Extraction
(a) extracting Xanthoceras sorbifolia powder of husks or branches or stems or leaves or kernels or roots or barks with organic solvent at ratio of 1:2 for 4-5 times for 20-35 hours each time to form an organic extract; (b) collecting the organic extract; (c) refluxing the organic extract for 2-3 times at 80° C. to form second extracts; (d) removing the organic solvent from the second extract; and (e) drying and sterilizing the extract to form a Xanthoceras sorbifolia extract powder.
Experiment 2
Analysis of Xanthoceras Sorbifolia Extract Components by HPLC Chromatography
Methods
HPLC. A C-18 reverse phase μbondapak column (Water P/N 27324) was equilibrated with 10% acetonitrile, 0.005% Trifluoroacetic acid (equilibration solution). An extract of Xanthoceras sorbifolia prepared using the methods described in Experiment 1 was dissolved in equilibration solution (1 mg/ml) before applying into the column. 20 ug of samples was applied into column. Elution conditions: Fractions were eluted (with flow rate 0.5 ml/min.) with acetonitrile gradient from 10% to 80% in 70 min, and then remains at 80% for 10 min. The acetonitrile concentration then decreased to 10% and remained at 10% for 25 min. The fractions were monitored at 207 nm and recorded in chart with a chart speed of 0.25 cm/min and with OD full scale of 0.128.
Instruments. Waters Model 510 Solvent Delivery System; Waters 484 tunable Absorbance Detector; Waters 745/745B Data Module.
Absorbance analysis. The absorption profile of Xanthoceras Sorbifolia extract at various wavelengths was determined. An extract of Xanthoceras sorbifolia of the present invention was dissolved in 10% acetonitrile/TFA and scanned at 200-700 nm with a spectrophotometer [Spectronic Ins. Model Gene Sys2].
Results
HPLC. About 60-70 peaks can be accounted for in the profile. Among them four are major peaks, 10 are of medium size and the rest are small fractions. The peaks are labelled with a to z following increased concentration of acetonitrile elution. See FIG. 8 .
Absorption maximum. Three absorption maximum were identified for Xanthoceras sorbifolia plant extract; 207 nm, 278 nm and 500 nm. See FIG. 57 .
Experiment 3
Determination of the Cell-Growth Activity Effected by Xanthoceras Sorbifolia Extract with Cancer Cells Derived from Different Human Organs using MTT Assay
Methods and Materials
Cells. Human cancer cell lines were obtained from American Type Culture Collection: HTB-9 (bladder), HeLa-S3 (cervix), DU145 (prostate), H460 (lung), MCF-7 (breast), K562 (leukocytes), HCT116 (colon), HepG2 (liver), U2OS (bone), T98G (brain) and OVCAR-3 (ovary). Cells were grown in culture medium (HeLa-S3, DU145, MCF-7, Hep-G2 and T98G in MEN (Earle's salts); HTB-9, H460, K562, OVCAR-3 in RPMI1640; HCT-116, U2OS in McCoy-5A) supplemented with 10% fetal calf serum, glutamine and antibiotics in a 5% CO2 humidified incubator at 37° C.
MTT assay. The procedure for MTT assay followed the method described in (Carmichael et al., 1987) with only minor modifications. Cells were seeded into a 96-wells plate at concentrations of 10,000/well (HTB-9, HeLa, H460, HCT116, T98G, OVCAR-3), 15,000/well (DU145, MCF-7, HepG2, U2OS), or 40,000/well (K562), for 24 hours before drug-treatment. Cells were then exposed to drugs for 48 hours (72 hours for HepG2, U2OS, and 96 hours for MCF-7). After the drug-treatment, MTT (0.5 mg/ml) was added to cultures for an hour. The formation of formazan (product of the reduction of tetrazolium by viable cells) was dissolved with DMSO and the O.D. at 490 nm was measured by an ELISA reader [Dynatech. Model MR700]. The MTT level of cells before drug-treatment was also measured (T0). The % cell-growth (% G) is calculated as:
% G= ( TD−T 0 /TC−T 0)×100 (1)
where TC or TD represent O.D. readings of control or drug-treated cells. When T0>TD, then the cytotoxicity (LC) expressed as % of the control is calculated as:
% LC =( TD−T 0 /T 0)×100. (2)
Results
Among the 11 cell lines studies, inhibition of cell-grwoth after exposure of plant extract was observed. However, their sensitivity toward Xanthoceras sorbifolia extract is different. It can be divided into four groups: Most sensitive, i.e., Ovary; Sensitive, i.e., bladder, bone; Semi-sensitive, i.e., prostate, leukocyte, liver, breast, and brain; and Least sensitive, i.e., colon, cervix, and lung. See FIGS. 14 , 15 and 16 A-D. Their IC50 values are listed in Table 3.1.
TABLE 3.1
IC50 values of Xanthoceras Sorbifolia Extract Determined
in Different Cancer Cells
IC50 determined by
Cancer cells from different organs
MTT assay (ug/ml)
Ovary (most sensitive)
15-15
Bladder (sensitive)
45-50
Bone
40-55
Prostate (Semi-sensitive)
40-50
Leukocyte
45-50
Liver
45-65
Breast
65
Brain
70-85
Colon (least sensitive)
90
Cervix
115
Lung
110
In addition to cell-growth inhibition, the Xanthoceras sorbifolia plant extract also stimulate a minor cell growth at low concentrations in bladder, bone and lung cells.
Results indicate that there is a cell or tissue stimulation component(s) in the extract. See FIGS. 16A and 16D .
To investigate the inhibition components of the Xanthoceras sorbifolia plant extract, the plant extract was fractionated. FIG. 10 shows the results of the screening of fractions obtained after FPLC chromatography for cell growth-inhibition activity. The assay was conducted with bladder cells. The fractions obtained from FPLC, as shown in FIG. 9 , were used. As shown in FIG. 9 , different components of Xanthoceras sorbifolia extracts cause either growth or inhibition effects on cells. Only fractions 5962, designated as Fraction Y, cause cell growth inhibition. Abscissa: concentration (ug/ml). Ordinate: % Cell Growth (determined by MTT assay).
Experiment 4
Purification of the Inhibition Components in the Xanthoceras Sorbifolia Extract.
(A) Fractionation of Plant Extracts with FPLC
Methods
Column. Octadecyl functionalized silica gel. Column dimension: 2 cm×28 cm; equilibrated with 10% acetonitrile—0.005% TFA before use.
Sample loading: 1-2 ml, concentration: 100 mg/ml in 10% acetonitrile/TFA.
Gradient elution condition: 10-80% acetonitrile in a total volume of 500 ml.
Monitor absorption wavelength: at 254 nm.
Fraction Collector: 5 ml/fractions (collect from 10% to 72% acetonitrile)
Instrument: AKTA-FPLC, P920 pump; Monitor UPC-900; Frac-900.
Results
The elution profile of the chromatography shows 4-5 broad fractions. See FIG. 9 . These fractions were analyzed with HPLC. Specific components, corresponding to a-z as specified in FIG. 8 , are then assigned in these FPLC fractions. FPLC fractions are then grouped into 7 pools and analyzed for cell growth activity in bladder cells with MTT assay. See Experiment 3. It was found that only pool #5962, corresponding to fraction Y in HPLC, contains inhibition activity. See FIG. 10 . It was also found in later experiments that fractions beyond 62 also show inhibition activity. The components isolated from fractions 63-65 showed inhibition activities. See FIGS. 4 , 12 and 13 .
(B) Isolation of Component Ys with Preparative HPLC
Methods
Column: A preparative HPLC column (Waters Delta Pak C18-300A);
Elution conditions: 45% acetonitrile isocratic elution with flow rate of 1 ml/min.
Fractions are monitored at 207 nm and were collected and lyophilized.
Results
Final separation of Y fractions was achieved by HPLC with a preparative column. See FIGS. 11 and 12 . These fractions, which include compound Y1, Y2, Y or Y3 and Y4, were collected. Re-chromatography of compound Y showed a single peak in HPLC with a C18 reverse phase column. See FIGS. 11A and 11B . Re-chromatography of the compound Y8, Y9 and Y10 showed a single peak in HPLC with a C18 reverse phase column. See FIG. 13 .
(C) Appearance and Solubility
The pure compound Ys is an amorphous white powder, soluble in aqueous alcohol, i.e., methanol or ethanol, 50% acetonitrile and 100% pyridine.
(D) Inhibition Analysis of Compound Ys with MTT Assay
Inhibition analysis of compound Y was determined with MTT assay. FIG. 2 shows that compound Y has activity against ovarian cancer cells (OCAR-3) with IC50 value of 1.5 ug/ml which is 10-15 times more potent than the unpurified extract shown in FIG. 14 .
FIG. 15 shows the selectivity of compound Y to ovarian cancer cells compared with cervical cancer cells (HeLa). FIG. 3 shows the inhibition activities of compound Y1 and Y2 on the growth of ovarian cancer cells (OCAR-3). FIG. 4 shows the inhibition activities of compound Y, Y8, Y9 and Y10 on the growth of ovarian cancer cells (OCAR-3).
Experiment 5
Determination of the Chemical Structure
Methods
NMR analysis. The pure compound Y of Xanthoceras sorbifolia was dissolved in pyridine-D5 with 0.05% v/v TMS. All NMR spectra were acquired using a Bruker Avance 600 MHz NMR spectrometer with a QXI probe (1H/13C/15N/31P) at 298 K. The numbers of scans for 1D 1H spectra were 16 to 128, depending on the sample concentration. 2D HMQC spectra were recorded with spectral widths of 6000×24,000 Hz and data points of 2024×256 for t2 and t1 dimensions, respectively. The number of scans were 4 to 128. 2D HMBC were acquired with spectral widths of 6000×30,000 Hz and data points of 2024×512 for t2 and t1 dimensions, respectively. The numbers of scans were 64. The 2D data were zero-filled in t1 dimension to double the data points, multiplied by cosine-square-bell window functions in both t1 and t2 dimensions, and Fourier-transformed using software XWIN-NMR. The final real matrix sizes of these 2D spectra are 2048×256 and 2048×512 data points (F2×F1) for HMQC and HMBC, respectively.
Mass spectral analysis. The mass of samples was analyzed by (A) MALDI-TOF Mass Spectrometry and by (B) ESI-MS Mass spectrometry. (A) Samples for MALDI-TOF were first dissolved in acetonitrile, and then mixed with the matrix CHCA, i.e., Alpha-cyano-4-hydroxycinnamic acid, 10 mg CHCA/mL in 50:50 water/acetonitrile and 0.1% TFA in final concentration. The molecular weight was determined by the high resolution mass spectroscope analysis with standards. (B) For ESI, the sample was analyzed with LCQ DECA XP Plus machine made by Thermo Finnigan. It is ionized with ESI source and the solvent for the compound is acetonitrile.
Results
The profile of the proton NMR is presented in FIG. 18 . The 2D NMR profiles of HMQC and HMBC are shown in FIGS. 19 and 20 , respectively.
Table 5.1 summarizes the 2D NMR chemical shift data and the assignment of functional groups derived from these data. Based on these data and analysis, the structure of compound Y (Y3) is assigned as shown below.
The chemical name of compound Y is: 3-O-[β-D-galactopyranosyl(1→2)]-α-L-arabinofuranosyl(1→3)-β-D-glucuronopyranosyl-21,22-O-diangeloyl-3β, 15α, 16α, 21β, 22α, 28-hexahydroxyolean-12-ene.
TABLE 5.1
13C and 1H NMR Data for Compound Y (in Pyridine-d5) a
Position
C
H
Key HMBC correlations
1
38.7
0.83, 1.40
C-3, C-5, C-9
2
26.4
1.81, 2.14
—
3
89.6
3.25, 1H, dd,
C-23, C-24, GlcA C-1′
12.0/4.0 Hz
4
39.4
—
—
5
55.3
0.78
—
6
18.5
1.55, 1.59
C-8, C-10
7
36.5
2.00, 2.10
C-5, C-9
8
41.2
—
—
9
47.0
3.06
C-7, C-8, C-12, C-14, C-26
10
37.2
—
—
11
23.7
1.74, 1.89
—
12
125.2
5.49, 1H, br s
C-9, C-11, C-14, C-18
13
143.4
—
—
14
47.5
—
—
15
67.3
4.21
C-8, C-27
16
73.6
4.45
C-14, C-15, C-18
17
48.3
—
—
18
40.8
3.07
C-12, C-13, C-14,
C-16, C-19, C-20, C-28,
19
46.8
1.41, 1.69
—
20
36.2
—
—
21
79.3
6.71, 1H, d, 10 Hz
C-20, C-22, C-29, C-30,
21-O-Ang C-1′′′′
22
73.5
6.32, 1H, d, 10 Hz
C-16, C-17, C-21, C-28,
22-O-Ang C-1′′′′
23
27.7
1.26, 3H, s
C-3, C-4, C-5, C-24
24
16.5
1.16, 3H, s
C-3, C-4, C-5, C-23
25
16.0
0.81, 3H, s
C-1, C-5, C-9, C-10
26
17.3
0.99, 3H, s
C-7, C-8, C-9, C-14
27
21.0
1.85, 3H, s
C-8, C-13, C-14, C-15
28
62.9
3.50, 1H, d, 11.0 Hz,
C-16, C-17, C-18, C-22
3.76, 1H, d, 11.0 Hz,
29
29.2
1.09, 3H, s
C-19, C-20, C-21, C-30
30
20.0
1.32, 3H, s
C-19, C-20, C-21, C-29
GlcA
1′
104.9
4.89, 1H, d, 7.8 Hz
C-3
2′
79.1
4.38
GlcA C-1′, C-3′, Gal C-1′′
3′
86.1
4.20
GlcA C-2′, C-4′, Ara C-1′′′
4′
71.5
4.42
GlcA C-3′, C-5′, C-6′
5′
78.0
4.52
GlcA C-4′, C-6′
6′
171.9
—
—
Gal
1′′
104.6
5.32, 1H, d, 7.7 Hz
GlcA C-2′
2′′
73.6
4.42
Gal C-1′′, C-3′′
3′′
74.9
4.10
Gal C-2′′
4′′
69.5
4.56
Gal C-2′′, C-3′′
5′′
76.4
3.94
Gal C-4′′, C-6′′
6′′
61.6
4.43, 4.52
Gal C-4′′, C-5′′
Ara-f
1′′′
110.6
6.03. 1H, br s
GlcA C-3′, Ara C-2′′′, C-4′′′
2′′′
83.4
4.94
Ara C-3′′′
3′′′
78.3
4.78
Ara C-2′′′
4′′′
85.2
4.82
Ara C-5′′′
5′′′
62.2
4.12, 4.28
Ara C-3′′′
21-O-Ang
1′′′′
167.7
—
—
2′′′′
129.6
—
—
3′′′′
137.2
5.96, 1H, dq, 7.0/1.5 Hz
Ang C-1′′′′, C-4′′′′, C-5′′′′
4′′′′
15.5
2.10, 3H, dq, 7.0/1.5 Hz
Ang C-2′′′′, C-3′′′′
5′′′′
20.8
2.00, 3H, s
Ang C-1′′′′, C-2′′′′, C-3′′′′
22-O-Ang
1′′′′
167.9
—
—
2′′′′
129.8
—
—
3′′′′
136.3
5.78, 1H, dq, 7.0/1.5 Hz
Ang C-1′′′′, C-4′′′′, C-5′′′′
4′′′′
15.5
1.93, 3H, dq, 7.0/1.5 Hz
Ang C-2′′′′, C-3′′′′
5′′′′
20.5
1.74, 3H, s
Ang C-1′′′′, C-2′′′′, C-3′′′′
a The data were assigned based on HMQC and HMBC correlations.
The mass spectrum of compound Y as determined by MALDI-TOF and ESI-MS, i.e., see FIG. 21 , 22 , indicates that the mass of compound Y is 1140.57 which agree with the theoretical mass of the compound Y.
Conclusion
The active compound Y isolated from extract of Xanthoceras sorbifolia is an oleanene triterpenoidal saponin with a trisaccharide chain attached at C-3 of the aglycone and two angeloyl groups acylated at C-21 and C-22. The formula of Y is C 57 H 88 O 23 , and the chemical name of Compound Y is: 3-O-[β-D-galactopyranosyl(1→2)]-α-L-arabinofuranosyl(1→3)-β-D-glucuronopyranosyl-21,22-O-diangeloyl-3β, 15α, 16α, 21β, 22α, 28-hexahydroxyolean-12-ene.
Experiment 6
Determination of the Chemical Structure of Compound Y1 of Xanthoceras Sorbifolia Extract
Methods
The method for NMR and MS analysis for compound Y1 is similar to the method described in Experiment 5.
Results
The spectrum of the H-NMR is presented in FIG. 24 . The 2D NMR spectra of HMQC, HMBC and COSY are shown in FIGS. 25 , 26 and 27 , respectively. Table 6.1 summarizes the chemical shift data and the assignment of functional groups derived from these data.
TABLE 6.1
13C and 1H NMR Data for Compound Y1 (in Pyridine-d5)
Position
C
H
1
38.6
0.85, 1.33
2
26.3
1.86, 2.10
3
89.7
3.25, 1H, dd
4
39.5
—
5
55.5
0.75
6
18.3
1.40, 1.43
7
33.1
1.20, 1.50
8
40.0
—
9
46.7
1.69
10
36.5
—
11
22.5
2.30
12
123.6
5.36, 1H, br s
13
143.5
—
14
41.8
—
15
34.7
1.53, 1.73
16
68.5
4.45
17
48.2
—
18
39.9
3.04
19
47.6
1.30, 3.05
20
36.7
—
21
85.3
5.05, 1H, d
22
73.8
6.17, 1H, d
23
27.7
1.29, 3H, s
24
16.5
1.16, 3H, s
25
15.5
0.81, 3H, s
26
17.1
0.82, 3H, s
27
20.6
1.83, 3H, s
28
63.7
3.42, 1H, d, 3.60, 1H, d
29
29.9
1.42, 3H, s
30
19.9
1.37, 3H, s
GlcA
1
105.0
4.88, 1H, d
2
79.0
4.37
3
86.0
4.20
4
71.6
4.43
5
78.0
4.50
6
171.8
—
Gal
1
104.5
5.31, 1H, d
2
73.5
4.43
3
74.9
4.10
4
69.5
4.57
5
76.3
3.95
6
61.1
4.44, 4.53
Ara-f
1
110.9
6.04. 1H, br s
2
83.3
4.95
3
78.3
4.78
4
85.2
4.82
5
62.0
4.13, 4.31
21-O-Rha
1
105.1
4.92, 1H, d
2
70.5
4.25
3
74.0
5.59
4
71.5
5.70
5
68.5
3.89
6
17.6
1.18, 3H, d
Rh-3-Ang
1
167.2
—
2
127.9
—
3
138.7
5.92, 1H, q
4
15.7
2.02, 3H, d
5
20.6
1.92, 3H, s
Rh-4-Ang
1
167.2
—
2
128.0
—
3
137.9
5.87, 1H, q
4
15.5
1.96, 3H, d
5
19.8
1.85, 3H, s
22-O-Ac
1
171.4
—
2
21.8
2.31, 3H, s
Based on these data and analysis, the structure of compound Y1 is assigned and shown below.
The chemical name of Y1 is: 3-O-[β-D-galactopyranosyl(1→2)]-α-L-arabinofuranosyl(1→3)-β-D-glucuronopyranosyl-21-O-(3,4-diangeloyl)-α-L-rhamnophyranosyl-22-O-acetyl-3β, 16α, 21β, 22α, 28-pentahydroxyolean-12-ene.
Conclusion
Compound Y1 isolated from extract of Xanthoceras sorbifolia is a bisdesmosidic polyhydroxyoleanene triterpenoidal saponin with a trisaccharide chain at C-3 of the backbone and a monosaccharide moiety at C-21 where two angeloyl groups were acylated at C-3 and C-4 position. The formula of Y1 is C 65 H 100 O 27 ,
Experiment 7
Determination of the Chemical Structure of Compound Y2 of Xanthoceras Sorbifolia Extract.
Methods
The method for NMR and MS analysis for compound Y2 is similar to the method described in Experiment 5.
Results
The 1D and 2D NMR spectra of H-NMR, C-13 NMR, HMQC, HMBC and (TOCSY) and MS (MALDI-TOF) of Y2 are showed in FIGS. 29-34 . Table 7.1 summarizes the 1D and 2D NMR chemical shift data and the assignment of functional groups derived from these data.
TABLE 7.1 13C and 1H NMR data for Y2 (in Pyridine-d5) a Position C H 1 38.4 0.83, 1.36 2 26.4 1.89, 2.25 3 91.3 3.39, 1H, m 4 43.4 — 5 56.7 0.87, 1H, d, 12.0 Hz 6 18.6 1.31, 1.57 7 36.3 1.97, 2.12 8 40.7 — 9 46.7 1.63 10 36.6 — 11 23.9 1.69, 1.89 12 125.1 5.48, 1H, br s 13 143.4 — 14 47.5 — 15 67.1 4.18, 1H, d, 4.1 Hz 16 73.2 4.43 17 48.1 — 18 41.4 3.06 19 46.6 1.40, 3.08 20 36.1 — 21 78.3 6.69, 1H, d, 10.2 Hz 22 73.1 6.30, 1H, d, 10.2 Hz 23 22.0 1.29, 3H, s 24 62.9 3.28, 1H, d, 11.2 Hz; 4.32 25 15.6 0.64, 3H, s 26 17.1 0.94, 3H, s 27 20.8 1.84, 3H, s 28 63.1 3.48, 3.72 (each, 1H, d, 10.6 Hz) 29 29.3 1.09, 3H, s 30 20.0 1.32, 3H, s 3-O-GlcA 1 104.5 4.87, 1H, d, 7.2 Hz 2 78.6 4.31 3 86.5 4.23 4 71.6 4.45 5 77.4 4.53 6 171.9 Glc 1 103.7 5.48, 1H, d, 7.8 Hz 2 75.3 4.02 3 78.0 4.31 4 69.3 4.52 5 78.2 3.62 6 61.5 4.33, 4.50 Ara 1 110.1 6.05, 1H, br s 2 83.5 4.97 3 77.8 4.74 4 85.0 4.84 5 62.2 4.18, 4.33 21-O-ang 1 167.5 — 2 128.7 — 3 137.2 5.95, 1H, dd, 14.4/7.2 Hz 4 16.7 2.08, 3H, d, 7.2 Hz 5 20.6 2.00, 3H, s 22-O-ang 1 167.9 — 2 128.9 — 3 136.3 5.76, 1H, dd, 14.4/7.2 Hz 4 15.6 1.95, 3H, dd, 7.2 Hz 5 20.4 1.74, 3H, s a The data were assigned based on COSY, HMQC and HMBC correlations.
Conclusion
Based on these data and analysis, the compound Y2 isolated from extract of Xanthoceras sorbifolia is an oleanene triterpenoidal saponin with a trisaccharide chain attached at C-3 of the aglycone and two angeloyl groups acylated at C-21 and C-22. The chemical structure of Y2 is shown below. See also FIG. 28 .
The formula of Y2 is C 57 H 88 O 24 , and the chemical name of Compound Y2 is: 3-O-[β-D-glucopyranosyl-(1→2)]-α-L-arabinofuranosyl(1→3)-β-D-glucuronopyranosyl-21,22-O-diangeloyl-3β, 15α, 16α, 21β, 22α, 24β, 28-heptahydroxyolean-12-ene.
Experiment 7B
Chemical Structure Analysis of Y4
Results of Y4 Analysis
The profile of the proton NMR of Y4 is presented in FIG. 58 . The profiles of 2D NMR (HMQC) of Y4 is presented in FIG. 59 .
Experiment 8
Purification of the Inhibition Components Y8-Y10 in the Xanthoceras Sorbifolia Extract
(A) Fractionation of Xanthoceras Sorbifolia Extracts Components with FPLC
Methods
The methods for this experiment are similar to the methods decribed in Experiment 4 Section (A) and (B).
Results
The elution profile shows 4-5 broad fractions. See FIG. 9 . These fractions were analyzed with HPLC. FPLC fractions 63, 64 and 65 are further separated on 45% isocratic analysis, 4-5 major components were separated ( FIG. 12 ). These fractions were assigned designations Y8, Y9 and Y10. These fractions were collected. Re-chromatography of the compound Y8, Y9 and Y10 showed a single peak in HPLC with a C18 reverse phase column. See FIG. 13 .
(B) Inhibition Analysis with MTT Assay.
Inhibition analysis of purified compounds was determined with the MTT assay. Results indicate that compound Y8, Y9 and Y10 has activity against ovarian cancer cells (OCAR-3) with IC50 values of 3, 4 and 1.5 ug/ml, respectively. See FIG. 4 .
Experiment 9
Determination of the Chemical Structure of Compound Y8 of Xanthoceras Sorbifolia Extract
Methods
The method for NMR and MS analysis for compound Y8 is similar to the method described in Experiment 5.
Results
The spectral profiles of the H-NMR, C13-NMR 2D NMR (HMQC) of compound Y8 are presented in FIGS. 36-38 .
Based on these data and analysis, the compound Y8 isolated from extract of Xanthoceras sorbifolia is an oleanene triterpenoidal saponin with a trisaccharide chain attached at C-3 of the aglycone and two angeloyl groups acylated at C-21 and C-22.
The formula of compound Y8 is C 57 H 87 O 23 , and the chemical name of Y8 is: 3-O-[β-glucopyranosyl(1→2)]-α-arabinofuranosyl(1→3)-β-glucuronopyranosyl-21,22-O-diangeloyl-3β, 16α, 21β, 22α, 24β, 28-hexahydroxyolean-12-ene.
The chemical structure of compound Y8 is presented in the following figure. See also FIG. 35 .
Experiment 10
Determination of the Chemical Structure of Compound Y9 of Xanthoceras Sorbifolia Extract
Methods
The method for NMR and MS analysis for compound Y9 is similar to the method described in Experiment 5.
Results
The spectral profiles of the H-NMR, 2D NMR, i.e., HMQC and HMBC, of Y9 are shown in FIGS. 40-42 .
Based on these data and analysis, compound Y9 isolated from extract of Xanthoceras sorbifolia is a bisdesmosidic polyhydroxyoleanene triterpenoidal saponin with a trisaccharide chain at C-3 of the backbone and a monosaccharide moiety at C-21 where two angeloyl groups were acylated at C-3 and C-4 position.
The formula of compound Y9 is C 63 H 98 O 26 , and the chemical name of Y9 is: 3-O-[β-galactopyranosyl(1→2)]-α-arabinofuranosyl(1→3)-β-glucuronopyranosyl-21-O-(3,4-diangeloyl)-α-rhamnopyranosyl-3β, 16α, 21β, 22α, 28-pentahydroxyolean-12-ene.
The chemical structure of Compound Y9 is presented in the following figure. See also FIG. 39 .
Experiment 11
Determination of the Chemical Structure of Compound Y10 of Xanthoceras Sorbifolia Extract
Methods
The method for NMR and MS analysis for compound Y10 is similar to the method described in Experiment 5.
Results
The profile of the H-NMR, C13-NMR and 2D NMR (HMQC) are shown in FIGS. 44-46 .
Based on these data and analysis, compound Y10 isolated from extract of Xanthoceras sorbifolia is an oleanene triterpenoidal saponin with a trisaccharide chain attached at C-3 of the aglycone and two angeloyl groups acylated at C-21 and C-22.
The formula of compound Y10 is C 57 H 87 O 22 , and the chemical name of Y10 is: 3-O-[β-galactopyranosyl(1→2)]-α-arabinofuranosyl(1→3)-β-glucuronopyranosyl-21,22-O-diangeloyl-3β, 16α, 21β, 22α, 28-pentahydroxyolean-12-ene.
The chemical structure of Compound Y10 is presented in the following figure. See also FIG. 43 .
Experiment 12
Purification of Component R from Xanthoceras Sorbifolia Extract
(A) Purification of Xanthoceras Sorbifolia Extracts Components with FPLC and HPLC
Methods
The methods used are similar to the methods described in Experiment 4, section (A) and (B) except a 30% acetonitrile isocratic elution was used in HPLC for isolation of the Compound R.
Results
Fraction No. 39-41 from gradient elution of FPLC were pooled and further purified with an open ODS-C18 column with isocratic 30% acetonitrile elution. Six identifiable fractions in two groups were collected. Fractions 6-13 were further characterized with HPLC.
These fractions were further separated into 4-5 components with the 30% acetonitrile isocratic elution in a DeltaPak column. The fraction designated herein as “R1”, is the major component. See FIG. 60A . The pure R1 was subsequently collected from the column elution. See FIG. 60B .
(B) Appearance and Solubility
The pure R1 appears as an amorphous white powder, soluble in aqueous alcohol, i.e., methanol or ethanol, 50% acetonitrile and 100% pyridine.
(C) Determination of the Chemical Structure of R1
Methods
The NMR and MS Analysis of R1 is similar to the method described in Experiment 5.
Results
The NMR spectra of pure R1 is presented in FIGS. 48-52 . Based on chemical shift analysis, compound R1 isolated from extract of Xanthoceras sorbifolia is a triterpenoid saponins with five sugars and one angeloyl group attached to the sugar moiety. The chemical structure of R1 is shown in following figure. See also FIG. 47 .
The formula of Compound R1 is C 65 H 106 O 29 , and the chemical name of R1 is: 3-O-[angeloyl-(1→3)-β-D-glucopyranosyl-(1→6)]-β-D-glucopyranosyl-28-O-[α-L-rhamnopyranosyl-(1→2)-β-D-glucopyranosyl-(1→6)-β-D-glucopyranosyl-3β, 21β, 22α, 28-tetrahydroxyolean-12-ene.
Experiment 13
Purification of Component-O from Xanthoceras Sorbifolia Extract
(A) Fractionation of Xanthoceras Sorbifolia Extracts Components with FPLC and HPLC
Methods
The methods used are similar to the methods described in Experiment 4, section (A) and (B) except a 20% acetonitrile isocratic elution was used in HPLC for isolation of the Compound O.
Results
Fractions obtained from FPLC were analyzed with HPLC. By comparison with the profiles of the original sample, a specific component, in this case fraction O, was identified (#28-30). Fraction O was collected for further purification. Sixteen identifiable HPLC fractions were observed in the elution profiles. See FIG. 61 . Fractions 28, 34 and 54 were further purified. See FIGS. 62-63 . These purified components are named as compound O28, O34 and O54, respectively.
(B) Appearance and Solubility
The purified compound O23 and O34 are light yellow amorphous powder, soluble in aqueous alcohol, i.e., methanol, ethanol, 50% acetonitrile and 100% pyridine. The purified compound O54 is a white amorphous powder, soluble in aqueous alcohol, i.e., methanol, ethanol, 50% acetonitrile and 100% pyridine.
(C) Structure Analysis of Compound O54
Methods
The NMR and MS analysis of O54 is similar to the method described in Experiment 5.
Results
The NMR spectra of compound O54 is presented in FIGS. 54-56 . Based on the chemical shift analysis, compound O54 isolated from extract of Xanthoceras sorbifolia is a bisdesmosidic polyhydroxyoleanene triterpenoidal glycoside with a disaccharide chain [βD-glucopyranosyl-(1→6)-β-D-glucopyranoside] affixed to C-3 and a trisaccharide chain [a-L-rhamnopyranosyl-(1→2)-β-D-glucopyranosyl-(1→6)-β-D-glucopyranosyl ester]attached to C-28. The chemical structure of compound O54 is presented in the following figure. See also FIG. 53 .
The formula of compound O54 is C 60 H 100 O 28 , and the chemical name of O54 is: 3-O-β-D-glucopyranosyl-(1→6)]-β-D-glucopyranosyl-28-O-[α-L-rhamnopyranosyl-(1→2)-β-D-glucopyranosyl-(1→6)-β-D-glucopyranosyl-3β, 21β, 22α, 28-tetrahydroxyolean-12-ene.
Although the present invention has been described in detail with particular reference to preferred embodiments thereof, it should be understood that the invention is capable of other different embodiments, and its details are capable of modifications in various obvious aspects. As is readily apparent to those skilled in the art, variations and modifications can be affected while remaining within the spirit and scope of the invention. Accordingly, the foregoing disclosure, description, and figures are for illustrative purpose only, and do not in any way limit the invention which is defined only by the claims.
REFERENCES
1. Carmichael, J., DeGraff, W. G., Gazdar, A. F., Minna, J. D. and Mitchell, J. B.: Evaluation of a tetrazolium-based semiautomated calorimetric assay: assessment of chemosensitivity testing. Cancer Res. 47:936-942 (1987).
2. Chen, Q. 1995. Methods of study on pharmacology of Chinese medicines. Press of People's Public Health, Beijing. p 892.
3. Huang, Zh. Sh., Liu, M. P., Chen, Ch. Zh. 1997. Study on effects of Yangshou Dan on improving learning and retention. Chinese Journal of combination of Chinese and west medicine, 9(17): 553.
4. Zhang, Y., Zhang, H. Y., Li, W. P. 1995. Study on effects of Anjifu on improving intelligence, Chinese Bulletin of Pharmacology, 11 (3): 233.
5. Yang, J., Wang, J., Feng, P. A. 2000. Study on effects of Naokkangtai capsule on improving learning and retention in mice, New Chinese Medicine and Clinical Pharmacology, 1(11): 29.
6. Yang, J., Wang, J., Zhang, J. Ch. 2000. Study on effects of Crude saponins of peonies on improving learning and retention in mice, Chinese journal of Pharmacology, 2(16): 46.
7. Xia, W. J., Jin, M. W., Zhang, L. 2000. Study on treatment of senile dementia caused by angio-aging with Didang tang, Pharmacology and Clinical of Chinese Medicines, 16 (4).
8. Bian, H. M., Yu, J. Z., Gong, J. N. 2000. Study on effects of Tongmai Yizhi capsule on improving learning and retention in mice, Pharmacology and Clinical of Chinese Medicines, 16 (5): 40.
9. Wei, X. L., Zhang, Y. X. 2000. Study of animal model for studying senile dementia, Chinese journal of Pharmacology, 8(16): 372.
10. Bureau of Medicinal Police, Department of Public Health. Guide line for study of effect of medicines for treatment of nervous system diseases, in Guidebook of study of new medicine. p 45.
11. Zhang, D. Sh., Zhang, J. T. 2000. Effects of crude Ginseng saponins on improving impairment induced by B-peptide, Chinese journal of Pharmacology, 8(16): 22.
|
Novel compounds such as compounds designated herein as Y or Y3, Y1, Y2, Y8, Y9 and Y10 are disclosed. These compounds have anticancer activity. The compounds of the present invention are obtainable from plants in the sapindaceae family, such as Xanthoceras sorbifolia , or other natural sources or products. The compounds of the present invention may also be synthesized chemically.
| 2
|
[0001] The invention relates to a method for the preparation for a crystalline form of 1-chloro-4-(β-D-glucopyranos-1-yl)- 2 -[4-((S)-tetrahydrofuran-3-yloxy)-benzyl]-benzene. In addition the invention relates to a crystalline form obtainable by such a method and the use of the crystalline form for preparing medicaments.
BACKGROUND OF THE INVENTION
[0002] The compound 1-chloro-4-(β-D-glucopyranos-1-yl)- 2 -[4-((S)-tetrahydrofuran-3-yloxy)-benzyl]-benzene (in the following referred to it as “compound A”) is described in the international patent application WO 2005/092877 and has the chemical structure according to formula A
[0000]
[0003] The compounds described therein have a valuable inhibitory effect on the sodium-dependent glucose cotransporter SGLT, particularly SGLT2.
[0004] The international patent application WO 2006/120208 describes various methods of synthesis of SGLT2 inhibitors, inter alia of the compound A.
[0005] A crystalline form of the compound A and a method for its preparation are described in the international application WO 2006/117359. As preferred solvents for example methanol, ethanol, isopropanol, ethyl acetate, diethylether, acetone, water and mixtures thereof are described for the crystallization process.
[0006] In the synthesis of the compound A, for example according to WO 2006/120208, it is observed that certain impurities may be found in the final substance. Furthermore it is found that crystallization processes as described in the WO 2006/117359 decrease the content of impurities and increase the purity of the compound, but not in a totally satisfactory manner.
[0007] It is well known to the one skilled in the art that in the pharmaceutical field highly pure compounds are desired. A very high purity may improve the stability in long-term storage. On the other hand impurities may be attributed to unwanted physico-chemical properties, for example hygroscopicity, or pharmacological side effects.
AIM OF THE INVENTION
[0008] The aim of the present invention is to find an advantageous method for preparing a crystalline form of a compound 1-chloro-4-(β-D-glucopyranos-1-yl)-2-[4-((S)-tetrahydrofuran-3-yloxy)-benzyl]-benzene; in particular a robust method with which the crystalline form may be obtained in a high purity, with a low content of certain impurities, and/or which allows the manufacture of the crystalline form in a commercial scale with a low technical expenditure and a high space/time yield.
[0009] Another aim of the present invention is to provide a crystalline form of 1-chloro-4-(β-D-glucopyranos-1-yl)-2-[4-((S)-tetrahydrofuran-3-yloxy)-benzyl]-benzene, in particular in a high purity.
[0010] A further aim of the present invention is to provide a pharmaceutical composition comprising the crystalline form.
[0011] Another aim of the present invention is to provide a use of the crystalline form.
[0012] Other aims of the present invention will become apparent to the skilled artisan directly from the foregoing and following description.
OBJECT OF THE INVENTION
[0013] In a first aspect the present invention relates to a method for preparing a crystalline form of a compound 1-chloro-4-(β-D-glucopyranos-1-yl)-2-[4-((S)-tetrahydrofuran-3-yloxy)-benzyl]-benzene comprising the following steps:
[0014] (a) dissolving the compound in a mixture of at least two solvents to form a solution wherein the first solvent is selected from the group of solvents consisting of toluene and tetrahydrofuran, and the second solvent is selected from the group of solvents consisting of methanol, ethanol, 1-propanol and 2-propanol, or the first solvent is ethanol and the second solvent is selected from the group of solvents consisting of ethylacetate, n-propylacetate and methylethylketone;
[0015] (b) storing the solution to precipitate the crystalline form of the compound out of solution;
[0016] (c) isolating the crystalline form of the compound from the solution.
[0017] It is found that with the method according to this invention the crystalline form can be obtained in a high purity and in a high yield, in particular at commercially viable scales. The method shows a low technical expenditure and a high space/time yield. Despite possible variations in the purity of the starting material the method yields the crystalline form in a high purity. In particular the following impurities of the formulas IMP.1 and IMP.2 can be depleted to a high degree:
[0000]
[0018] In another aspect the present invention relates to the crystalline form of a compound 1-chloro-4-(β-D-glucopyranos-1-yl)-2-[4-((S)-tetrahydrofuran-3-yloxy)-benzyl]-benzene obtainable by a process as described hereinbefore and hereinafter.
[0019] In another aspect the present invention relates to the crystalline form of a compound 1-chloro-4-(β-D-glucopyranos-1-yl)-2-[4-((S)-tetrahydrofuran-3-yloxy)-benzyl]-benzene having an X-ray powder diffraction pattern that comprises peaks at 18.84, 20.36 and 25.21 degrees 2Θ (±0.1 degrees 2Θ), wherein said X-ray powder diffraction pattern is made using CuK α1 radiation, characterized by a purity above 99% as measured by HPLC.
[0020] In yet another aspect the present invention relates to a pharmaceutical composition comprising the crystalline form as described hereinbefore and hereinafter.
[0021] In yet another aspect the present invention relates to a use of the crystalline form as described hereinbefore and hereinafter for preparing a pharmaceutical composition which is suitable for the treatment or prevention of metabolic disorders, in particular of a metabolic disorder selected from the group consisting of type 1 and type 2 diabetes mellitus, complications of diabetes, metabolic acidosis or ketosis, reactive hypoglycaemia, hyperinsulinaemia, glucose metabolic disorder, insulin resistance, metabolic syndrome, dyslipidaemias of different origins, atherosclerosis and related diseases, obesity, high blood pressure, chronic heart failure, oedema and hyperuricaemia.
[0022] Further aspects of the present invention become apparent to the one skilled in the art from the following detailed description of the invention and the examples.
BRIEF DESCRIPTION OF THE FIGURES
[0023] The FIG. 1 shows a background corrected X-ray powder diffractogram of the crystalline form of the compound A.
[0024] The FIG. 2 shows the thermoanalysis via DSC of the crystalline form of the compound A.
DETAILED DESCRIPTION OF THE INVENTION
[0025] This crystalline form of the compound A may be identified by means of their characteristic X-ray powder diffraction (XRPD) patterns, in particular as described in the WO 2006/117359.
[0026] The crystalline form is characterised by an X-ray powder diffraction pattern that comprises peaks at 18.84, 20.36 and 25.21 degrees 2Θ (±0.1 degrees 2Θ), wherein said X-ray powder diffraction pattern is made using CuK α1 radiation.
[0027] In particular said X-ray powder diffraction pattern comprises peaks at 14.69, 18.84, 19.16, 19.50, 20.36 and 25.21 degrees 2Θ (±0.1 degrees 2Θ), wherein said X-ray powder diffraction pattern is made using CuK α1 radiation.
[0028] Said X-ray powder diffraction pattern is even more characterised by peaks at 14.69, 17.95, 18.84, 19.16, 19.50, 20.36, 22.71, 23.44, 24.81 and 25.21 degrees 2Θ (±0.1 degrees 2Θ), wherein said X-ray powder diffraction pattern is made using CuK α1 radiation.
[0029] More specifically, the crystalline form of the compound A is characterised by an X-ray powder diffraction pattern, made using CuK α1 radiation, which comprises peaks at degrees 2Θ (±0.1 degrees 2Θ) as contained in the Table 1 of WO 2006/117359 or as contained in the Table 1 of the Experiment A of the present application or as shown in the FIG. 1 of WO 2006/117359 or as shown in the FIG. 1 of the present application.
[0030] Furthermore the crystalline form of the compound A is characterised by a melting point of about 151° C.±5° C. (determined via DSC; evaluated as onset-temperature; heating rate 10 K/min).
[0031] The X-ray powder diffraction patterns are recorded, within the scope of the present invention, using a STOE-STADI P-diffractometer in transmission mode fitted with a location-sensitive detector (OED) and a Cu-anode as X-ray source (CuKα1 radiation, λ=1.54056 Å, 40 kV, 40 mA).
[0032] In order to allow for experimental error, the above described 2Θ values should be considered accurate to ±0.1 degrees 2Θ, in particular ±0.05 degrees 2Θ. That is to say, when assessing whether a given sample of crystals of the compound A is the crystalline form in accordance with the invention, a 2 Θ value which is experimentally observed for the sample should be considered identical with a characteristic value described above if it falls within ±0.1 degrees 2Θ, in particular ±0.05 degrees 2Θ of the characteristic value.
[0033] The melting point is determined by DSC (Differential Scanning calorimetry) using a DSC 821 (Mettler Toledo).
[0034] The present invention relates to a method for preparing a crystalline form of the compound A comprising the following steps:
[0035] (a) dissolving the compound A in a mixture of at least two solvents to form a solution wherein the first solvent is selected from the group of solvents consisting of toluene and tetrahydrofuran, and the second solvent is selected from the group of solvents consisting of methanol, ethanol, 1-propanol and 2-propanol, or the first solvent is ethanol and the second solvent is selected from the group of solvents consisting of ethylacetate, n-propylacetate and methylethylketone;
[0036] (b) storing the solution to precipitate the crystalline form of the compound A out of solution;
[0037] (c) isolating the crystalline form of the compound A from the solution.
[0038] The first solvent is preferably selected from the group of solvents consisting of toluene and tetrahydrofuran.
[0039] The second solvent is preferably selected from the group of solvents consisting of methanol, ethanol, 1-propanol and 2-propanol; even more preferably from the group of solvents consisting of ethanol, 1-propanol and 2-propanol.
[0040] According to a preferred alternative the first solvent is ethanol and the second solvent is n-propylacetate or ethylacetate.
[0041] Examples of mixtures of at least two solvents are toluene/methanol, toluene/ethanol, toluene/1-propanol, toluene/2-propanol, tetrahydrofuran/methanol, tetrahydrofuran/ethanol, tetrahydrofuran/1-propanol, tetrahydrofuran/2-propanol, ethanol/n-propylacetate, ethanol/ethylacetate, ethanol/methylethylketone.
[0042] Preferred examples of mixtures of at least two solvents are toluene/ethanol, toluene/1-propanol, toluene/2-propanol, tetrahydrofuran/ethanol, tetrahydrofuran/1-propanol, tetrahydrofuran/2-propanol, ethanol/n-propylacetate, ethanol/ethylacetate.
[0043] The weight ratio of the first solvent to the second solvent is preferably in the range from about 1:10 to 10:1, more preferably from about 1:5 to 5:1, even more preferably from about 1:2 to 2:1, most preferably about 1:1.
[0044] With regard to the preferred examples toluene/ethanol, toluene/1-propanol, toluene/2-propanol, ethanol/n-propylacetate, ethanol/ethylacetate the weight ratio of the first solvent to the second solvent is preferably in the range from about 1:5 to 5:1, more preferably from about 1:2 to 2:1, most preferably about 1:1.
[0045] With regard to the preferred examples tetrahydrofuran/ethanol, tetrahydrofuran/1-propanol, tetrahydrofuran/2-propanol, the weight ratio of the first solvent to the second solvent is preferably in the range from about 1:10 to 2:1, more preferably from about 1:5 to 1:1, even more preferably from about 1:4 to 1:2.
[0046] In the step (a) the compound A may be employed in an amorphous or crystalline form or as a solution, for example obtained in the synthesis of the compound A.
[0047] Preferably the solution obtained in the step (a) is a saturated or nearly saturated solution at the given temperature.
[0048] The terms “saturated” or “nearly saturated” are related to the starting material of the compound A as used in step (a). For example a solution which is saturated with respect to the starting material of the compound A may be supersaturated with respect to its crystalline form.
[0049] The weight ratio of the compound A relative to the mixture of solvents is preferably in the range 1:8 to 1:2, more preferably 1:6 to 1:3, even more preferably from 1:5 to 1:4.
[0050] In the step (a) the solution may be heated up to the boiling temperature of the solution or to a temperature in the range from about 60° C. to 120° C., for example about 100° C. The solution obtained in the step (a) may be filtered, for example over charcoal.
[0051] At the beginning of the step (b) seeding crystals of the compound A are preferably added to the solution obtained in the step (a), optionally after a filtration step. The amount of the seeding crystals relative to the total amount of the compound A may be in the range from up to about 5 weight-%, more preferably from about 0.001 to 1 weight-%. The seeding crystals may be obtained for example by a process as described in the WO 2006/117359. The seeding crystals are preferably added at a temperature in the range from about 30° C. to 80° C., most preferably about 60 to 75° C. Alternatively the crystallization may be induced by methods as known in the art, for example by scratching or rubbing.
[0052] In the step (b) the temperature is preferably lowered in order to obtain a high yield of the precipitated crystalline form of the compound A. The temperature may be lowered continuously or via a predefined cooling ramp. An example of a cooling ramp is within about 30 min to 60±5° C., then within about 90 min to 50±5° C., then within about 60 min to 40±5° C., then within about 60 min to 25±5° C. A preferred final temperature at the end of the step (b) is in the range from about −10° C. to 40° C., more preferably from about 0° C. to 35° C., most preferably from about 10° C. to 30° C.
[0053] The duration of the step (b) may be in the range from about 30 min to 48 hours, preferably from about 3 to 6 hours.
[0054] The step (b) can be carried out with or without stirring. As known to the one skilled in the art by the period of time and the difference of temperature in step (b) the size, shape and quality of the obtained crystals can be varied.
[0055] In the step (c) the obtained crystals are isolated, for example via centrifugation or filtration. The obtained crystals are preferably washed with a solvent or a mixture of solvents, wherein the solvent is preferably selected from the group consisting of methanol, ethanol, 1-propanol, 2-propanol or tert.-butylmethylether. The most preferred solvent is ethanol. Preferably remaining solvent(s) are advantageously removed from the crystals in a drying step, preferably at a temperature in the range from about 0° C. to 100° C., for example from about 50° C. to 80° C. The temperature, the pressure and the duration of this drying step may be chosen in order to lower the content of one or more solvents below a given value. For example the content of toluene in the crystalline form may be chosen to be equal or below 890 ppm, preferably below 500 ppm, even more preferably below 300 ppm. The content of ethanol in the crystalline form may be chosen to be equal or below 5000 ppm, preferably below 2000 ppm, even more preferably below 1000 ppm.
[0056] The compound A may be synthesized by methods as specifically and/or generally described or cited in the international application WO 2005/092877. Furthermore the biological properties of the compound A may be investigated as it is described in the international application WO 2005/092877 which in its entirety is incorporated herein by reference.
[0057] The crystalline form in accordance with the invention is preferably employed as drug active substance in substantially pure form, that is to say, essentially free of other crystalline forms of the compound A. Nevertheless, the invention also embraces the crystalline form as herein defined in admixture with another crystalline form or forms. Should the drug active substance be a mixture of crystalline forms, it is preferred that the substance comprises at least 50% of the crystalline form as described herein.
[0058] According to another aspect of the present invention the crystalline form of the compound A having an X-ray powder diffraction pattern that comprises peaks at 18.84, 20.36 and 25.21 degrees 2Θ (±0.1 degrees 2Θ), wherein said X-ray powder diffraction pattern is made using CuK α1 radiation is characterized by a purity above 99% as measured by HPLC. Preferably the purity is above 99.5%, even more preferably above 99.7%, most preferably above 99.8%.
[0059] In a preferred embodiment the crystalline form as defined hereinbefore is characterized by a content of the compound of the formula IMP.1
[0000]
[0000] equal or below 1.00% as measured by HPLC. Preferably the content of the compound of the formula IMP.1 is equal or below 0.15%, even more preferably equal or below 0.05% as measured by HPLC.
[0060] In another preferred embodiment the crystalline form as defined hereinbefore is characterized by a content of the compound of the formula IMP.2
[0000]
[0000] equal or below 0.15% as measured by HPLC. Preferably the content of the compound of the formula IMP.2 is equal or below 0.05% as measured by HPLC.
[0061] According to a more preferred embodiment the crystalline form is characterized by a content of the compounds of the formulas IMP.1 and IMP.2 as defined above.
[0062] The hereinbefore and hereinafter mentioned purity and impurity may be determined with methods known to the one skilled in the art. Preferably the purity and impurity is measured via HPLC. The purity is preferably determined as 100% minus the sum of all quantified impurities.
[0063] Preferably the HPLC device is equipped with a C18 column, in particular a column with a microparticulate C18 packing used for reversed-phase HPLC, for example prepared by chemically bonding a sterically-protected C18 stationary phase (e.g. diisobutyl n-octadecylsilane) to porous silica microspheres (e.g. with a pore size of about 80 Å). Advantageous dimensions of the column and microspheres are 4.6 mm (inner dimension)×50 mm column and 1.8 μm. A UV-detection is preferred, for example at 224 nm.
[0064] Typical parameters for such a HPLC are:
[0065] Device: HPLC with UV-detection
[0066] Column: C18, 1.8 μm, 50*4.6 mm
[0067] Column temperature: 20° C.
[0068] Gradient:
[0000]
time (min)
eluent A (%)
eluent B (%)
0
100
0
1
70
30
4
70
30
8
5
95
12
5
95
[0069] Flow rate: 1.5 mL/min
[0070] Analysis time: 12 min
[0071] Equilibration time: 4 min
[0072] Injection volume: 8 μl
[0073] Detection: 224 nm
[0074] Preferred eluents are:
[0075] Eluent A: water+0.1% trifluoroacetic acid
[0076] Eluent B: acetonitrile+0.1% trifluoroacetic acid
[0077] A preferred solvent for the samples or as blank solution is a 50/50 (v/v) mixture of acetonitrile/water. Preferably all solvents including water are HPLC grade.
[0078] In view of their ability to inhibit the SGLT activity, the crystalline form according to the invention is suitable for the preparation of pharmaceutical compositions for the treatment and/or preventative treatment of all those conditions or diseases which may be affected by the inhibition of the SGLT activity, particularly the SGLT-2 activity. Therefore, the crystalline form is particularly suitable for the preparation of pharmaceutical compositions for prevention or treatment of diseases, particularly metabolic disorders, or conditions such as type 1 and type 2 diabetes mellitus, complications of diabetes (such as e.g. retinopathy, nephropathy or neuropathies, diabetic foot, ulcers, macroangiopathies), metabolic acidosis or ketosis, reactive hypoglycaemia, hyperinsulinaemia, glucose metabolic disorder, insulin resistance, metabolic syndrome, dyslipidaemias of different origins, atherosclerosis and related diseases, obesity, high blood pressure, chronic heart failure, oedema and hyperuricaemia. The crystalline form is also suitable for the preparation of pharmaceutical compositions for preventing beta-cell degeneration such as e.g. apoptosis or necrosis of pancreatic beta cells. The crystalline form is also suitable for the preparation of pharmaceutical compositions for improving or restoring the functionality of pancreatic cells, and also of increasing the number and size of pancreatic beta cells. The crystalline form according to the invention may also be used for the preparation of pharmaceutical compositions useful as diuretics or antihypertensives and suitable for the prevention and treatment of acute renal failure.
[0079] By the administration of the crystalline form according to this invention an abnormal accumulation of fat in the liver may be reduced or inhibited. Therefore according to another aspect of the present invention there is provided a method for preventing, slowing, delaying or treating diseases or conditions attributed to an abnormal accumulation of liver fat in a patient in need thereof characterized in that a pharmaceutical composition according to the present invention is administered. Diseases or conditions which are attributed to an abnormal accumulation of liver fat are particularly selected from the group consisting of general fatty liver, non-alcoholic fatty liver (NAFL), non-alcoholic steatohepatitis (NASH), hyperalimentation-induced fatty liver, diabetic fatty liver, alcoholic-induced fatty liver or toxic fatty liver.
[0080] In particular, the crystalline form according to the invention is suitable for the preparation of pharmaceutical compositions for the prevention or treatment of diabetes, particularly type 1 and type 2 diabetes mellitus, and/or diabetic complications.
[0081] In addition the crystalline form according to the invention is particularly suitable for the prevention or treatment of overweight, obesity (including class I, class II and/or class III obesity), visceral obesity and/or abdominal obesity.
[0082] The dosage required to achieve the corresponding activity for treatment or prevention usually depends on the patient, the nature and gravity of the illness or condition and the method and frequency of administration and is for the patient's doctor to decide. Expediently, the dosage may be from 1 to 100 mg by oral route, in each case administered 1 to 4 times a day. For this purpose, the pharmaceutical compositions according to this invention preferably comprise the crystalline form together with one or more inert conventional carriers and/or diluents. Such pharmaceutical compositions may be formulated as conventional galenic preparations such as plain or coated tablets, capsules, powders, suspensions or suppositories.
[0083] The following example of synthesis serves to illustrate a method of preparing the compound A and its crystalline form. It is to be regarded only as a possible method described by way of example, without restricting the invention to its contents.
[0084] Determination of the Purity or Impurity Via HPLC:
[0085] This method is used for the determination of organic impurities in the compound A. The quantification is carried out via external standard solutions. The reagents (acetonitrile, water, trifluoroacetic acid (TFA)) are use in HPLC grade. The term “compound A xx ” denotes the crystalline form of the compound A as obtained with a method according to this invention.
[0086] Mobile Phase
[0087] Eluent A: water+0.1% TFA
[0088] Eluent B: acetonitrile+0.1% TFA
[0089] Solutions
[0090] Solvent: acetonitrile/water (50/50 (v/v))
[0091] Blank solution: solvent
[0092] Solution 1
[0093] A solution with a concentration of 0.5 mg/ml of the compound IMP.2 is prepared; e.g. 25 mg of the substance are weighed, dissolved in 2 mL of methanol and diluted with solvent to a total volume of 50 mL.
[0094] System Suitability Solution (SST)
[0095] A solution with a concentration of 0.5 mg/ml of the compound A xx is prepared, containing approx. 0.5% IMP.2; e.g. 25 mg of the compound A xx are weighed, dissolved in 2 mL of methanol (via ultrasound) and, after addition of 250 μL of solution 1, diluted with solvent to a total volume of 50 mL. Optional, approx. 0.5% of the following possible impurities may be added: IMP.1
[0096] Reporting Limit (0.05%)
[0097] A solution with 0.05% of the nominal concentration is prepared. Therefore, 50 μl of a stem solution is diluted with solvent to a total volume of 100 mL
[0098] Sample Solutions
[0099] A solution of the substance to be analyzed is prepared with a concentration of 0.8 mg/mL. Therefore, e.g. 40 mg of the substance are weighed, dissolved in 2 mL of methanol and diluted with solvent to a total volume of 50 mL. This solution is prepared twice.
[0100] Stem Solutions
[0101] A solution of the compound A xx is prepared with a concentration of 0.8 mg/mL. Therefore, e.g. 40 mg of the substance are weighed, dissolved with 2 mL of methanol and diluted with solvent to a total volume of 50 mL. This solution is prepared twice.
[0102] Reference Solution (0.5%)
[0103] A solution of compound A xx with a concentration of 4 μg/ml compared to the nominal weighed sample is prepared. Therefore, e.g. 250 μl of the stem solution are diluted with 50 mL. This solution is prepared twice (once from each stem solution).
[0104] Chromatographic Parameters:
[0105] Device: HPLC with UV-detection
[0106] Column: Zorbax SB-C18, 1.8 μm, 50*4.6 mm, (manufacturer: Agilent)
[0107] Column temperature: 20° C.
[0108] Gradient:
[0000]
time (min)
eluent A (%)
eluent B (%)
0
100
0
1
70
30
4
70
30
8
5
95
12
5
95
[0109] Flow rate: 1.5 mL/min
[0110] Analysis time: 12 min
[0111] Equilibration time: 4 min
[0112] Injection volume: 8 μl
[0113] Detection: 224 nm
[0114] Injections:
[0000]
Solutions
Injections
Blank solution
n ≧ 1
Reporting limit
1
Reference solution 1
2
Reference solution 2
2
SST
1
Blind solution
n ≧ 1
Sample 1, Solution 1
2
Sample 1, Solution 2
2
Sample 2, Solution 1
2
Sample 2, Solution 2
2
Further samples
2 each
SST
1
[0115] Typical Retention Times:
[0116] The order of elution of the peaks in the chromatogram of the SST-solution should correspond to a example chromatogram. The peak assignment is carried out with a example chromatogram or via the relative retention times (RRTs).
[0000]
RT
Substance
(approx. min)
RRT
IMP.1
3.35
0.84
Compound A XX
3.97
1.00
IMP.2 Isomer 1
4.97
1.25
IMP.2 Isomer 2
5.19
1.31
[0117] Evaluation:
[0118] The calculation of the content of the impurities is carried out according to the following formula.
[0000]
%
Impurity
=
PF
Sample
_
*
V
Sample
EW
Sample
_
*
EW
Stem
Solution
_
*
Potency
Reference
Substance
PF
0
,
5
Comparison
_
*
V
Stem
Solution
*
VF
*
100
[0119] PF x : Peak areas
[0120] EW x : weigh-in
[0121] Vx: volume to which the dilution is carried out
[0122] VF: dilution factor
[0123] Potency: known potency in % of the compound A xx reference substance
[0124] The purity of a sample of the compound A is calculated as 100% minus the sum of all quantified impurities.
[0125] Preparation of the Compound A:
[0126] The terms “room temperature” or “ambient temperature” denote a temperature of about 20° C.
[0127] GC gas chromatography
[0128] hrs hours
[0129] i-Pr iso-propyl
[0130] Me methyl
[0131] min minute(s)
[0132] THF tetrahydrofuran
[0000]
Example 1
Synthesis of the Fluoride VIII.1
[0133] Oxalylchloride (176 kg; 1386 mol; 1.14 eq) is added to a mixture of 2-chloro-5-iodo benzoic acid (343 kg; 1214 mol) (compound IX.1), fluorobenzene (858 kg) and N,N-dimethylformamide (2 kg) within 3 hours at a temperature in the range from about 25 to 30° C. (gas formation). After completion of the addition, the reaction mixture is stirred for additional 2 hours at a temperature of about 25 to 30° C. The solvent (291 kg) is distilled off at a temperature between 40 and 45° C. (p=200 mbar). Then the reaction solution (911 kg) is added to aluminiumchloride AlCl 3 (181 kg) and fluorobenzene (192 kg) at a temperature between about 25 and 30° C. within 2 hours. The reaction solution is stirred at the same temperature for about an additional hour. Then the reaction mixture is added to an amount of 570 kg of water within about 2 hours at a temperature between about 20 and 30° C. and stirred for an additional hour. After phase separation the organic phase (1200 kg) is separated into two halves (600 kg each). From the first half of the organic phase solvent (172 kg) is distilled off at a temperature of about 40 to 50° C. (p=200 mbar). Then 2-propanole (640 kg) is added. The solution is heated to about 50° C. and then filtered through a charcoal cartouche (clear filtration). The cartouche may be exchanged during filtration and washed with a fluorobenzene/2-propanole mixture (1:4; 40 kg) after filtration. Solvent (721 kg) is distilled off at a temperature of about 40 to 50° C. and p=200 mbar. Then 2-propanole (240 kg) is added at a temperature in the range between about 40 to 50° C. If the content of fluorobenzene is greater than 1% as determined via GC, another 140 kg of solvent are distilled off and 2-propanole (140 kg) is added. Then the solution is cooled from about 50° C. to 40° C. within one hour and seeding crystals (50 g) are added. The solution is further cooled from about 40° C. to 20° C. within 2 hours. Water (450 kg) is added at about 20° C. within 1 hour and the suspension is stirred at about 20° C. for an additional hour before the suspension is filtered. The filter cake is washed with 2-propanole/water (1:1; 800 kg). The product is dried until a water level of <0.06% w/w is obtained. The second half of the organic phase is processed identically. A total of 410 kg (94% yield) of product which has a white to off-white crystalline appearance, is obtained. The identity of the product is determined via infrared spectrometry.
Example 2
Synthesis of the Ketone VII.1
[0134] To a solution of the fluoride VIII.1 (208 kg), tetrahydrofuran (407 kg) and (S)-3-hydroxytetrahydrofuran (56 kg) is added potassium-tert-butanolate solution (20%) in tetrahydrofuran (388 kg) within 3 hrs at 16 to 25° C. temperature. After completion of the addition, the mixture is stirred for 60 min at 20° C. temperature. Then the conversion is determined via HPLC analysis. Water (355 kg) is added within 20 min at a temperature of 21° C. (aqueous quench). The reaction mixture is stirred for 30 min (temperature: 20° C.). The stirrer is switched off and the mixture is left stand for 60 min (temperature: 20° C.). The phases are separated and solvent is distilled off from the organic phase at 19 to 45° C. temperature under reduced pressure. 2-Propanol (703 kg) is added to the residue at 40 to 46° C. temperature and solvent is distilled off at 41 to 50° C. temperature under reduced pressure. 2-Propanol (162 kg) is added to the residue at 47° C. temperature and solvent is distilled off at 40 to 47° C. temperature under reduced pressure. Then the mixture is cooled to 0° C. within 1 hr 55 min. The product is collected on a centrifuge, washed with a mixture of 2-propanol (158 kg) and subsequently with tert.-butylmethylether (88 kg) and dried at 19 to 43° C. under reduced pressure. 227 kg (91.8%) of product are obtained as colourless solid. The identity of the product is determined via infrared spectrometry.
Example 3
Synthesis of the Iodide V.1
[0135] To a solution of ketone VII.1 (217.4 kg) and aluminium chloride (AlCl 3 ; 81.5 kg) in toluene (366.8 kg) is added 1,1,3,3-tetramethyldisiloxane (TMDS, 82.5 kg) within 1 hr 30 min (temperature: 18-26° C.). After completion of the addition, the mixture is stirred for additional 1 hr at a temperature of 24° C. Then the conversion is determined via HPLC analysis. Subsequently the reaction mixture is treated with acetone (15.0 kg), stirred for 1 hr 5 min at 27° C. temperature and the residual TMDS content is analyzed via GC. Then a mixture of water (573 kg) and concentrated HCl (34 kg) is added to the reaction mixture at a temperature of 20 to 51° C. (aqueous quench). The reaction mixture is stirred for 30 min (temperature: 51° C.). The stirrer is switched off and the mixture is left stand for 20 min (temperature: 52° C.). The phases are separated and solvent is distilled off from the organic phase at 53-73° C. temperature under reduced pressure. Toluene (52.8 kg) and ethanol (435.7 kg) are added to the residue at 61 to 70° C. temperature. The reaction mixture is cooled to 36° C. temperature and seeding crystals (0.25 kg) are added. Stirring is continued at this temperature for 35 min. Then the mixture is cooled to 0 to 5° C. and stirred for additional 30 min. The product is collected on a centrifuge, washed with ethanol (157 kg) and dried at 15 to 37° C. under reduced pressure. 181 kg (82.6%) of product are obtained as colourless solid. The identity of the product is determined via the HPLC retention time.
Example 4
Synthesis of the Lactone IV.1
[0136] A suspension of the D-(+)-gluconic acid-delta-lactone IVa.1 (42.0 kg), tetrahydrofuran (277.2 kg), 4-methylmorpholine (NMM; 152.4 kg) and 4-dimethylaminopyridine (DMAP; 1.44 kg) is treated with chlorotrimethylsilane (TMSCl; 130.8 kg) within 50 min at 13 to 19° C. After completion of the addition stirring is continued for 1 hr 30 min at 20 to 22° C. and the conversion is determined via HPLC analysis. Then n-heptane (216.4 kg) is added and the mixture is cooled to 5° C. Water (143 kg) is added at 3 to 5° C. within 15 min. After completion of the addition the mixture is heated to 15° C. and stirred for 15 min. The stirrer is switched off and the mixture is left stand for 15 min. Then the phases are separated and the organic layer is washed in succession two times with water (143 kg each). Then solvent is distilled off at 38° C. under reduced pressure and n-heptane (130 kg) is added to the residue. The resulting solution is filtered and the filter is rinsed with n-heptane (63 kg) (filter solution and product solution are combined). Then solvent is distilled off at 39 to 40° C. under reduced pressure. The water content of the residue is determined via Karl-Fischer analysis (result: 0.0%). 112.4 kg of the product is obtained as an oil (containing residual n-heptane, which explains the yield of >100%). The identity of the product is determined via infrared spectrometry.
Example 5a Synthesis of the Glucoside II.1
[0137] To a solution of the iodide V.1 (267 kg) in tetrahydrofuran (429 kg) is added Turbogrignard solution (isopropylmagnesium chloride/lithium chloride solution, 14 weight-% iPrMgCl in THF, molar ratio LiCl:iPrMgCl=0.9-1.1 mol/mol) (472 kg) at −21 to −15° C. temperature within 1 hr 50 min. On completion of the addition the conversion is determined via HPLC analysis. The reaction is regarded as completed when the area of the peak corresponding to the iodide V.1 is smaller than 5.0% of the total area of both peaks, iodide V.1 and the corresponding desiodo compound of iodide V.1. If the reaction is not completed, additional Turbogrignard solution is added until the criterion is met. In this particular case the result is 3.45%. Then the lactone IV.1 (320 kg) is added at −25 to −18° C. temperature within 1 hr 25 min. The resulting mixture is stirred for further 1 hr 30 min at −13 to −18° C. On completion of the addition the conversion is determined via HPLC analysis (for information). On completion, a solution of citric acid in water (938 L; concentration:10%-weight) is added to the reaction mixture of a volume of about 2500 L at −13 to 19° C. within 1 hr 25 min. The solvent is partially distilled off from the reaction mixture (residual volume: 1816-1905 L) at 20 to 30° C. under reduced pressure and 2-methyltetrahydrofuran (532 kg) is added. Then the stirrer is switched off and the phases are separated at 29° C. After phase separation the pH value of the organic phase is measured with a pH electrode (Mettler Toledo MT HA 405 DPA SC) or alternatively with pH indicator paper (such as pH-Fix 0-14, Macherey and Nagel). The measured pH value is 2 to 3. Then solvent is distilled off from the organic phase at 30 to 33° C. under reduced pressure and methanol (1202 kg) is added followed by the addition of a solution of 1.25N HCl in methanol (75 kg) at 20° C. (pH=0). Full conversion to the acetale III.1 is achieved by subsequent distillation at 20 to 32° C. under reduced pressure and addition of methanol (409 kg).
[0138] Completion of the reaction is obtained when two criteria are fulfilled:
[0139] 1) The ratio of the sum of the HPLC-area of the alpha-form+beta-form of intermediate III.1 relative to the area of intermediate IIIa.1 is greater or equal to 96.0%:4.0%.
[0140] 2) The ratio of the HPLC-area of the alpha-form of intermediate III.1 to the beta-form of III.1 is greater or equal to 97.0% to 3.0%.
[0141] In this particular case both criteria are met. Triethylamin (14 kg) is added (pH=7.4) and solvent is distilled off under reduced pressure, acetonitrile (835 kg) is added and further distilled under reduced pressure. This procedure is repeated (addition of acetonitrile: 694 kg) and methylene chloride (640 kg) is added to the resulting mixture to yield a mixture of the acetale III.1 in acetonitrile and methylene chloride. The water content of the mixture is determined via Karl Fischer titration (result: 0.27%). The reaction mixture is then added within 1 hr 40 min at 10 to 19° C. to a preformed mixture of AlCl 3 (176 kg), methylene chloride (474 kg), acetonitrile (340 kg), and triethylsilane (205 kg). The resulting mixture is stirred at 18 to 20° C. for 70 min. After completion of the reaction, water (1263 L) is added at 20 to 30° C. within 1 hr 30 min and the mixture is partially distilled at 30 to 53° C. under atmospheric pressure and the phases are separated. Toluene (698 kg) is added to the organic phase and solvent is distilled off under reduced pressure at 22 to 33° C. The product is then crystallized by addition of seeding crystals (0.5 kg) at 31° C. and water (267 kg) added after cooling to 20° C. The reaction mixture is cooled to 5° C. within 55 min and stirred at 3 to 5° C. for 12 hrs. Finally the product is collected on a centrifuge as colourless, crystalline solid, washed with toluene (348 kg) and dried at 22 to 58° C. 211 kg (73%) of product are obtained. The identity of the product is determined via the HPLC retention time.
Example 5b
Synthesis of the Glucoside II.1
[0142] To a solution of the iodide V.1 (30 g) in tetrahydrofuran (55 mL) is added Turbogrignard solution (isopropylmagnesium chloride/lithium chloride solution, 14 weight-% iPrMgCl in THF, molar ratio LiCl:iPrMgCl=0.9-1.1 mol/mol) (53 g) at −14 to −13° C. temperature within 35 min. On completion of the addition the conversion is determined via HPLC analysis. The reaction is regarded as completed when the area of the peak corresponding to the iodide V.1 is smaller than 5.0% of the total area of both peaks, iodide V.1 and the corresponding desiodo compound of iodide V.1. If the reaction is not completed, additional Turbogrignard solution is added until the criterion is met. In this particular case the result is 0.35%. Then the lactone IV.1 (36 g) is added at −15 to −6° C. temperature within 15 min. The resulting mixture is stirred for further 1 hr at −6 to −7° C. On completion, the conversion is determined via HPLC analysis (for information). On completion, a solution of citric acid in water (105 mL; concentration:10%-weight) is added to the reaction mixture at −15 to 10° C. within 30 min. The solvent is partially distilled off from the reaction mixture (residual volume: 200 mL) at 20 to 35° C. under reduced pressure and 2-methyltetrahydrofuran (71 mL) is added. Then the mixture is stirred for 25 min at 30° C. Then the stirrer is switched off and the phases are separated at 30° C. After phase separation the pH value of the organic phase is measured with a pH electrode (Mettler Toledo MT HA 405 DPA SC) or alternatively with pH indicator paper (such as pH-Fix 0-14, Macherey and Nagel). The measured pH value is 3. Then solvent is distilled off from the organic phase at 35° C. under reduced pressure and methanol (126 mL) is added followed by the addition of a solution of 1.25N HCl in methanol (10.1 mL) at 25° C. (pH=1-2). Full conversion to the acetale III.1 is achieved by subsequent distillation at 35° C. under reduced pressure and addition of methanol (47 mL).
[0143] Completion of the reaction is obtained when two criteria are fulfilled:
[0144] 1) The ratio of the sum of the HPLC-area of the alpha-form+beta-form of intermediate III.1 relative to the area of intermediate IIIa.1 is greater or equal to 96.0%:4.0%. In this particular case the ratio is 99.6%:0.43%.
[0145] 2) The ratio of the HPLC-area of the alpha-form of intermediate III.1 to the beta-form of III.1 is greater or equal to 97.0% to 3.0%. In this particular case the ratio is 98.7%:1.3%.
[0146] Triethylamin (2.1 mL) is added (pH=9) and solvent is distilled off at 35° C. under reduced pressure, acetonitrile (120 mL) is added and further distilled under reduced pressure at 30 to 35° C. This procedure is repeated (addition of acetonitrile: 102 mL) and methylene chloride (55 mL) is added to the resulting mixture to yield a mixture of the acetale III.1 in acetonitrile and methylene chloride. The water content of the mixture is determined via Karl Fischer titration (result: 0.04%).
[0147] The reaction mixture is then added within 1 hr 5 min at 20° C. to a preformed mixture of AlCl 3 (19.8 g), methylene chloride (49 mL), acetonitrile (51 mL), and triethylsilane (23 g). The resulting mixture is stirred at 20 to 30° C. for 60 min. After completion of the reaction, water (156 mL) is added at 20° C. within 25 min and the mixture is partially distilled at 55° C. under atmospheric pressure and the phases are separated at 33° C. The mixture is heated to 43° C. and toluene (90 mL) is added and solvent is distilled off under reduced pressure at 41 to 43° C. Then acetonitrile (10 mL) is added at 41° C. and the percentage of acetonitrile is determined via GC measurement. In this particular case, the acetonitrile percentage is 27%-weight. The product is then crystallized by addition of seeding crystals (0.1 g) at 44° C. and the mixture is further stirred at 44° C. for 15 min. The mixture is then cooled to 20° C. within 60 min and water (142 mL) is added at 20° C. within 30 min. The reaction mixture is cooled to 0 to 5° C. within 60 min and stirred at 3° C. for 16 hrs. Finally the product is collected on a filter as colourless, crystalline solid, washed with toluene (80 mL) and dried at 20 to 70° C. 20.4 g (62.6%) of product are obtained. The identity of the product is determined via the HPLC retention time.
[0148] Preparation of the Crystalline Form:
[0149] Experiment A:
[0150] A solution of the compound A (79.0 kg) in a mixture of toluene (186.6 kg) and ethanol (187.2 kg) is heated to reflux until complete dissolution and filtered (hot filtration). The filter is washed with toluene (19.6 kg) and the washing solution is combined with the product solution. The product solution is then cooled to 66° C. and seeding crystals (0.1 kg) are added. The product solution is then cooled to 22° C. using a defined cooling ramp: within 30 min to 57° C., then within 90 min to 50° C., then within 60 min to 41° C., then within 60 min to 22° C. Then the suspension is further stirred at 21° C. for 1 hr, collected on a centrifuge and washed with ethanol (124.8 kg) and dried at about 70° C. 65.5 kg (82.9%) of the product is obtained as white crystals with a HPLC purity of 99.9%.
[0151] Via differential scanning calorimetry (DSC) as described hereinbefore, a melting point of 151° C. is determined ( FIG. 2 ).
[0152] Via X-ray powder diffraction as described hereinbefore, using CuK α1 radiation, the crystalline form is characterised and a pattern as shown in the FIG. 1 is obtained. The intensity shown in the FIG. 1 is given in units of cps (counts per second) and is background corrected.
[0153] In addition the crystalline form is characterised by the following lattice parameters: orthorhombic symmetry, space group P2 1 2 1 2 1 with the cell parameters, a=5.70(1) Å, b=9.25(2) Å, c=39.83(1) Å, and cell volume=2101(1) Å3 which can be obtained by indexing of the X-ray powder diagram to be measured at room temperature using CuK α1 radiation, which comprises peaks at degrees 2Θ (±0.1 degrees 2Θ) as contained in Table 1. In the Table 1 above the values “2Θ[°]” denote the angle of diffraction in degrees and the values “d [Å]” denote the specified distances in Å between the lattice planes. Furthermore the h, k, l indices are provided and the difference between the experimental and the calculated d-values in Å.
[0000]
TABLE 1
Indexed* X-ray powder diffraction pattern of the crystalline form (only
peaks up to 30° in 2 Θ are listed):
2 Θ
d-value
Intensity I/I 0
Indexing
d exp-calc
[°]
[Å]
[%]
h
k
l
[Å]
4.43
19.93
10
0
0
2
−0.003
8.86
9.97
3
0
0
4
−0.010
9.82
9.00
3
0
1
1
0.014
11.63
7.60
2
0
1
3
−0.020
13.32
6.64
22
0
0
6
−0.001
14.66
6.04
36
0
1
5
−0.005
15.69
5.64
50
1
0
1
−0.001
16.16
5.48
16
1
0
2
−0.006
17.92
4.95
71
1
0
4
−0.001
18.30
4.84
24
0
1
7
0.011
18.40
4.82
26
1
1
1
−0.002
18.81
4.71
100
1
1
2
0.000
19.13
4.64
67
1
0
5
0.000
19.46
4.56
31
1
1
3
−0.002
20.34
4.36
67
1
1
4
−0.005
20.52
4.33
25
1
0
6
−0.003
21.15
4.20
7
0
2
4
−0.006
21.43
4.14
13
1
1
5
0.003
22.06
4.03
35
1
0
7
0.002
22.68
3.92
30
1
1
6
0.001
23.42
3.80
20
0
2
6
0.006
23.71
3.75
8
1
0
8
0.003
24.08
3.69
5
1
1
7
0.003
24.31
3.66
9
0
1
10
0.007
24.77
3.59
14
1
2
0
0.007
25.18
3.53
30
1
2
2
0.004
25.62
3.47
29
1
1
8
0.007
26.36
3.38
3
1
2
4
0.003
26.84
3.32
16
0
0
12
0.003
27.24
3.27
16
1
1
9
−0.010
27.87
3.20
2
0
2
9
0.001
28.22
3.16
2
1
2
6
−0.002
28.98
3.08
5
1
1
10
0.001
29.39
3.04
15
1
2
7
0.010
29.55
3.02
3
0
2
10
−0.016
*For indexing the lattice parameters from single crystal analysis are used as starting values.
[0154] Refined cell parameters from XRPD-pattern:
[0155] all peaks (35) up to 30° Θ indexed
[0156] symmetry: orthorhombic
[0157] space group: P2 1 2 1 2 1
[0158] a=5.70(1) Å
[0159] b=9.25(2) Å
[0160] c=39.83(1) Å
[0161] α=β=γ=90°
[0162] V=2101(1) Å 3
[0163] Figure of merit: 118
[0164] Experiment B:
[0165] In the following experiment it is investigated how the method according to this invention is able to deplete an impurity of the formula IMP.1 as described hereinbefore.
[0166] The compound of the formula IMP.1 is added to the crystalline form of the compound A as obtained according to the Experiment A such that the amounts according to the Table 2 are obtained. For example in order to obtain the 0.5 weight-% mixture 6.96 g of the crystalline form of the compound A as obtained according to the Experiment A and 0.04 g the compound IMP.1 are combined.
[0167] Thereafter half of this mixture of compounds is recrystallized according to the procedure of the Experiment A on a laboratory scale. The crystalline form of compound A is obtained as a white crystalline material. The content of the compound of the formula IMP.1 is analyzed via HPLC.
[0168] The other half of this mixture of compounds is recrystallized using a mixture of methanol and water according to the following procedure:
[0169] About 7 g of a mixture of the crystalline form of the compound A as obtained according to the Experiment A and the compound IMP.1 is added to a mixture of methanol (7.1 g) and water (7.3 g) and is heated to 60° C. until complete dissolution. The clear solution is stirred for 15 min. Then water (11.9 g) is added to the solution and after completion of the addition the solution is cooled to 57° C. and seeding crystals are added. The solution is then further stirred at 57° C. for 30 min. The product solution is then cooled to 25° C. within 2 hrs and 20 min. Then the suspension is further stirred at 25° C. for 15 min, collected on a filter and washed with a mixture of methanol (1.66 g) and water (9.5 g) and dried at about 45° C. 6.5 g (93.1%) of the product is obtained as white crystals.
[0170] The compound A is obtained as a white crystalline material. The content of the compound of the formula IMP.1 is analyzed via HPLC.
[0000]
TABLE 2
Amount of the impurity IMP.1 in the compound A
Before
After recrystallization
After recrystallization
recrystallization
using toluene/ethanol
using methanol/water
(weight-%)
(HPLC-%)
(HPLC-%)
0.5%
0.07%
0.07%
1.0%
0.06%
0.12%
1.5%
0.07%
0.85%
2.0%
0.09%
0.67%
3.0%
0.14%
1.68%
5.0%
0.34%
3.05%
[0171] It is observed that using a crystallization process with a mixture of toluene and ethanol a better depletion of the impurity IMP.1 can be obtained than with a process using a methanol/water mixture.
[0172] Experiment C:
[0173] In the following experiment it is investigated how the method according to this invention is able to deplete an impurity of the formula IMP.2 as described hereinbefore.
[0174] Different samples of raw material of the compound A, for example as obtained from a not optimized lab-scale procedure according to Example 5a or 5b, are analyzed via HPLC with respect to their content of IPM.2.
[0175] Thereafter each sample is recrystallized according to the procedure of the Experiment A on a laboratory scale using a mixture of toluene and ethanol to obtain the crystalline form of compound A. The content of IPM.2 and the overall purity of the crystalline form of compound A is analyzed via HPLC.
[0000]
TABLE 3
Content of IMP.2
Content of IMP.2
Overall purity after
before
after
recrystallization using
recrystallization
recrystallization
toluene/ethanol
(HPLC-%)
(HPLC-%)
(HPLC-%)
Yield
0.89%
0.05%
99.95%
90.1%
1.26%
0.14%
99.86%
89.3%
1.75%
0.13%
99.82%
87.1%
2.75%
0.17%
99.72%
86.1%
3.94%
0.29%
99.61%
79.1%
7.30%
0.51%
99.21%
73.3%
[0176] Experiment D:
[0177] In the following experiment it is investigated how the method according to this invention is able to purify raw material of the compound A.
[0178] Different samples of raw material of the compound A, for example as obtained from a not optimized lab-scale procedure according to Example 5a or 5b, are analyzed via HPLC with respect to their purity.
[0179] Thereafter each sample is recrystallized according to the procedure of the Experiment A on a laboratory scale using a mixture of toluene and ethanol to obtain the crystalline form of compound A. The overall purity of the crystalline form of compound A is analyzed via HPLC.
[0180] The other half of each sample is recrystallized using a mixture of methanol and water according to the procedure as described in the Experiment B.
[0181] The purities of the samples of the raw material and the crystallized material are given in the Table 4.
[0000]
TABLE 4
Purity after
Purity after
Purity before
recrystallization using
recrystallization using
recrystallization
toluene/ethanol
methanol/water
(HPLC-%)
(HPLC-%)
(HPLC-%)
96.17%
99.82%
98.25%
96.74%
99.84%
99.64%
97.09%
99.80%
99.26%
97.43%
99.81%
99.54%
95.60%
99.75%
98.63%
[0182] It is observed that using a crystallization process with a mixture of toluene and ethanol a higher purity of the compound A can be obtained than with a process using a methanol/water mixture.
[0183] Experiment E:
[0184] In the following experiment the influence of the solvent mixture and ratio on the purity and yield of the recrystallization procedure according to Experiment A is investigated.
[0185] Therefore, a sample of the of raw material of the compound A, for example as obtained according to Example 5a or 5b, is analyzed via HPLC with respect to its purity and the result is found to be 95.16%. Then, this sample is recrystallized according to the procedure of Experiment A on a laboratory scale (compound A: 35 g; sum of first and second solvent: 162 g) with the modification that the two solvents ethanol and toluene are replaced against the given solvent mixtures in Table 5 to obtain the crystalline form of compound A. The overall purity of the crystalline form of compound A is analyzed via HPLC.
[0000]
TABLE 5
Overall purity after
Solvent system
recrystallization
(ratio weight:weight)
(HPLC-%)
Yield
Ethanol/Toluene = 1:1
99.72%
80.8%
1-Propanol/Toluene = 1:1
99.80%
82.2%
2-Propanol/Toluene = 1:1
99.72%
72.0%
Methanol/Toluene = 1:4
99.69%
54.6%
Ethanol/Tetrahydrofuran = 4:1
99.62%
82.9%
2-Propanol/Tetrahydrofuran = 2:1
99.67%
67.9%
Ethanol/n-Propylacetate = 1:1
99.68%
79.1%
Ethanol/Methylethylketone = 1:1
99.61%
67.1%
Ethanol/Ethylacetate = 1:1
99.70%
78.4%
[0186] Experiment F:
[0187] In the following experiment it is investigated how the method according to this invention is able to purify raw material of the compound A in comparison to a procedure using a mixture of ethanol and water (see for example the experiment “Variant 2” in WO 2006/117359).
[0188] A sample of raw material of the compound A, for example as obtained from a not optimized lab-scale procedure according to Example 5a or 5b, is analyzed via HPLC with respect to their purity.
[0189] Thereafter the sample is recrystallized according to the procedure of the Experiment A on a laboratory scale using a mixture of toluene and ethanol to obtain the crystalline form of compound A. The overall purity of the crystalline form of compound A is analyzed via HPLC.
[0190] The other half of the sample is recrystallized using a mixture of ethanol and water according to the following procedure:
[0191] 40 g of compound A are dissolved in 200 mL of water/ethanol mixture (2:3 volume ratio) upon heating up to about 50° C. 320 mL of water are added at a temperature range of 45 to 50° C. and the solution is allowed to cool to about 20° C. in 1 to 3 hrs.
[0192] After 16 hrs the crystalline form is isolated as beige crystals by filtration. The product is dried at elevated temperature (40 to 50° C.) for about 4 to 6 hrs.
[0193] The purities of the samples of the raw material and the crystallized material are given in the Table 6.
[0000]
TABLE 6
Purity after
Purity after
Purity before
recrystallization using
recrystallization using
recrystallization
toluene/ethanol
ethanol/water
(HPLC-%)
(HPLC-%)
(HPLC-%)
96.14%
99.74%
97.4%
[0194] It is observed that using a crystallization process with a mixture of toluene and ethanol a higher purity of the compound A can be obtained than with a process using an ethanol/water mixture.
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The invention relates to a method for the preparation for a crystalline form of 1-chloro-4-(β-D-glucopyranos-1-yl)-2-[4-((S)-tetrahydrofuran-3-yloxy)-benzyl]-benzene. In addition the invention relates to a crystalline form obtainable by this method, to a pharmaceutical composition and to the use thereof for preparing medicaments.
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CROSS REFERENCE TO RELATED APPLICATIONS
[0001] The present application claims benefit of U.S. Provisional application Ser. No. 60/672,770 filed on Apr. 19, 2005.
BACKGROUND OF THE INVENTION
[0002] Lock or gang boxes are commonly used by contractors in the construction industry to provide a secure place for them to store their tools safely overnight or during other periods when they are not present to prevent others from taking their tools. These lock boxes typically use padlocks that are part of a locking mechanism which keeps the lid of the box closed and prevents its opening after the tools have been placed within the box and the padlock has been locked. Frequently, the padlock is situated within a pocket such that its body only partially protrudes therefrom even when the padlock is in an open configuration and the shank is substantially inaccessible at all times, preventing someone from cutting it with bolt cutters.
[0003] The disadvantage that these prior art lock boxes have is that they all have some of the internal moving parts of the locking mechanism attached to the front panel of the lock box. The resulting structure, which is necessary to accommodate the moving parts of the locking mechanism, creates obstructions that reduce the user's accessibility to the inside of the box for storage and also creates catch points upon which items may get stuck when trying to remove items from the box. Accordingly, there exists a need for a lock box that has a locking mechanism that maximizes the accessibility to the interior of the box and minimizes the difficulty of taking items out of the box.
[0004] Furthermore, some of these prior art boxes require that the padlock be removed before the box can be opened. This can lead to the padlock being lost, creating frustration and additional cost for replacing the padlock for the end user. Other prior art boxes require that some lever or other member that is connected to the locking mechanism be moved after the padlock has been unlocked to actually unlock the box. These same boxes require that this same lever be moved back to a locked position before the padlock and box can be locked. This is an inefficient method for locking and unlocking boxes and an improvement is needed in order to reduce the time it takes for a user to lock and unlock such a box.
SUMMARY OF THE INVENTION
[0005] The present invention includes a lock box that has a lid, a side panel, and a locking mechanism that has all of its internal moving components attached solely to the lid. This allows a user to easily access the interior of the lock box when the box is open, without creating obstructions for putting items into the box or catch points for taking items out of the box. This box may also include a padlock that is also attached to the lid and that is substantially inaccessible from the outside, preventing any tampering with the locking mechanism and enhancing the security of the lock box.
[0006] A lock box that has a lid, a right side panel, a left side panel, a bottom panel, a front panel, and a back panel may also achieve the present invention. It also includes a locking mechanism that has a padlock and internal moving components that are all attached solely to the lid, allowing a user to easily access the interior of the lock box when the box is open. The construction of the locking mechanism may also be such that unlocking or locking the padlock is all that is necessary to lock and or unlock the box without having to move another lever or member that is connected to the locking mechanism or remove the padlock.
[0007] This construction allows a user to use the lock box in the following manner. The user unlocks the padlock, which causes the locking mechanism to be unlocked without having to remove the padlock from the lock box or move another member that is part of the locking mechanism. Then the user pulls up on the lid so that the interior of the box can be accessed. Then the user can place an object into or take an object out of the box. Then the user pushes down on the lid until the padlock is ready to be locked. Finally, the padlock is locked, which causes the locking mechanism to lock the box without having to move a lever or another member that is mechanically coupled to the locking mechanism or having to attach a padlock to the box.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is a perspective view of a lock box of the preferred embodiment of the present invention having a lid of the lock box in an open configuration;
[0009] FIG. 2 is a perspective view of a lock box of the preferred embodiment of the present invention having a lid of the lock box in a closed and locked configuration;
[0010] FIG. 3 is a side elevational view of the locking mechanism of the lock box of FIG. 2 taken along section line 3 - 3 ;
[0011] FIG. 4 is a side elevation view of the locking mechanism of the lock box of FIG. 3 in an open configuration;
[0012] FIG. 5 is a perspective view of the locking mechanism, removed from the lock box;
[0013] FIG. 6 is a top plan view of the locking mechanism of FIG. 5 , removed from the lock box;
[0014] FIG. 7 is a bottom plan view of the locking mechanism of FIG. 5 , removed from the lock box;
[0015] FIG. 8 is a cross-sectional view of the locking mechanism of FIG. 5 taken along section line 8 - 8 ;
[0016] FIG. 9 is a partially exploded side elevational view of the locking mechanism components;
[0017] FIG. 10 is a perspective view of the shroud; and
[0018] FIG. 11 is a-perspective view of the locking tang.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0019] Looking at FIGS. 1 and 2 , there is shown the preferred embodiment of a lock box 10 that satisfies the aforementioned need. It comprises, in part, a lid 11 , a front panel 12 , a right side panel 14 , a left side panel 16 , a back panel 18 , a bottom panel 20 , skids 22 , handles 24 , a locking mechanism 26 , locking support arms 28 , and finger slot 29 . FIG. 1 shows the lock box 10 in an open configuration where the locking support arms 28 are temporarily fixed using known means, allowing the user to place tools into the box 10 without fear of the lid 11 falling onto some part of the user, causing injury. It should be noted that the entire locking mechanism 26 is attached only to the lid 11 , minimizing any obstructions that could get in the way of the user placing items into or removing items from the space found between the front panel 12 , right side panel 14 , left side panel 16 , back panel 18 , and bottom panel 20 of the lock box 10 .
[0020] Once the user has placed all the items, such as tools, he wishes into the lock box 10 , he can then disengage the locking support arms 28 , allowing him to then pull onto the lid 11 , which is hingedly connected to the top of the back panel 18 , until it bottoms out onto the top of the front panel 12 , right side panel 14 , left side panel 16 , and back panel 18 . Finally, the user pushes onto the padlock 30 until it locks, causing the locking mechanism 26 to engage the front panel 12 of the lock box 10 without having to move another member that is part of the locking mechanism 26 or attaching the padlock 30 . The lock box 10 is now locked, preventing anyone from lifting the lid 11 and accessing the items contained therein.
[0021] When the lock box 10 is in this closed configuration as shown in FIG. 2 , the padlock 30 is substantially inaccessible making any tampering with it impractical. Furthermore, the user can then move the lock box 10 easily by lifting and pulling onto one of the handles 24 , one of which is attached near the top of the exterior of the right panel 14 while the other is attached to the top of the exterior of the left panel 16 , until the lock box 10 slides on one of the skids 22 , which is attached to the underside of the bottom panel 20 and is opposite of that handle 24 . Alternatively, the box 10 could roll on casters (not shown), which can be attached via prepunched holes (not shown) located on the bottom of the skids 22 .
[0022] Referring now to FIGS. 3-7 , the construction of the locking mechanism 26 and the way it works can be clearly seen. The locking mechanism 26 comprises a padlock 30 , a shroud 32 , a connecting rod 34 , locking tangs 36 , a keep 38 , screws 42 , and flanges 44 . The open configuration of the locking mechanism 26 is created in the following manner. First, the user uses the key to unlock the padlock 30 by inserting a key into the keyhole 45 located at the front of the body 46 of the padlock 30 . Then the internal spring 31 of the padlock 30 causes the body 46 of the padlock 30 to move away from the generally hook shaped shank 48 , which is fixedly attached to the shroud 32 . This creates an extra half-inch of clearance between the body 46 of the padlock 30 and the shank 48 . Then the three locking tangs 36 , which are fixedly attached to the connecting rod 34 , are free to rotate away from the front panel 12 until they reach an equilibrium position where there is no interference between them and the lip 50 located near the top of the front panel 12 . This motion is created because the moment about the center of the connecting rod 34 that is produced by the hook portion 52 of the locking tang 36 is greater than that created by the push tab portion 54 of the locking tang 36 .
[0023] Once this open configuration of the locking mechanism 26 has been achieved, then the user, who places his hand within the finger slot 29 located at the front edge 51 of the lid 11 and pulls upward, can open the lid 11 . It should be noted that no movement of another lever or other member that is part of the locking mechanism 26 is necessary to unlock the box 10 unlike other boxes. Also, the user does not need to remove the padlock 30 from the box 10 . These features save time and prevent user frustration.
[0024] Conversely, the closed configuration is achieved in the following manner. First, the user pushes onto the padlock 30 , overcoming the internal spring 31 force until the body 46 of the padlock 30 contacts the push tab portion 54 of the locking tang 36 , overcoming the moment produced by the weight of the hook portion 52 of the locking tang 36 . This causes all three locking tangs 36 and the connecting rod 34 to rotate until the padlock 30 locks and the hook portions 52 of all three locking tangs 36 are caught beneath the lip 50 of the front panel 12 . The lid 11 cannot be lifted at this point until the padlock 30 is unlocked. There will often be a slight gap between the locking tangs 36 and the lip 50 of the front panel 12 even after the padlock 30 has been locked due to manufacturing tolerances. Therefore, it is advantageous to have a piece of rubber (not shown) or some other suitably resilient material to take up this slop and prevent any unwanted rattling between the locking tang 36 and the lip 50 of the front panel 12 .
[0025] FIGS. 8, 9 , 10 , and 11 show how the locking mechanism 26 is assembled and attached to the lid 11 of the lock box 10 . First, the shroud 32 is inserted through an opening located in the front edge 51 of the lid 11 . This shroud 32 is configured to support, house, and protect the padlock 30 . Then the center locking tang 36 is inserted from the bottom of the shroud 32 until its hole 56 aligns with the side holes 58 (only one of which is shown) of the shroud 32 . Next, the connecting rod 34 slides through the holes 56 , 58 of the shroud 32 and locking tang 36 . Then, the flanges 44 are slid onto either end of the connecting rod 34 and positioned equidistant distance from the centerline of the shroud 32 where they are welded onto the underside of the lid 11 . Next, the outside locking tangs 36 are slid onto the connecting rod 34 . Then, all three locking tangs 36 are welded onto the connecting rod 34 in such a way that they are all substantially aligned. Next, the padlock 30 is inserted into the shroud 32 until its shank 48 bottoms out on the back of the shroud 32 . Then the keep 38 is inserted from the bottom of the shroud 32 such that it captures the inside surface of the shank 48 of the padlock 30 , holding the shank 48 of the padlock 30 in a fixed orientation. Finally, the keep 38 is held into place vertically by the screws 42 , which are fastened onto the shroud 32 (best seen in FIGS. 3, 4 , 8 , and 9 ). The locking mechanism 26 is then ready to operate.
[0026] It should also be noted that the flanges 44 and shroud 32 are affixed to the lid 11 such that their rear surfaces press up against the bolster panel 60 that is also attached to the underside of the lid 11 . The bolster panel 60 provides increased rigidity to the lid 11 , helping to prevent anyone from prying the box 10 open. This enhances the overall security of the box 10 .
[0027] As can be seen, this embodiment provides a lock box 10 that does not have any movable components of the locking mechanism 26 attached to any side panel, resulting in easy access to its interior. Furthermore, the locking mechanism 26 is constructed such that no movement of another member of the locking mechanism 26 is necessary to lock or unlock the box 10 , nor is it necessary to remove the padlock 30 at anytime. It should be appreciated that the spirit and scope of this invention could be achieved with other types of mechanisms including those that operate in a similar manner but only vary the number and position of locking tangs 36 and padlocks 30 . Therefore, the scope of this invention should be interpreted in view of the attached claims.
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A lock box with an obstruction free interior is provided that comprises a locking mechanism that has all of its internal moving components attached solely to the lid, making it easy for the user to put items into or take items out of the box. Furthermore, the locking mechanism is constructed so that locking and unlocking the box requires only the simple step of locking or unlocking the padlock.
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BACKGROUND
Organic light emitting diodes (OLEDs) are useful in a wide range of lighting applications, as well as high and low resolution display devices. They have been made both with low molecular-weight organic materials and with polymers. For full-color applications, it is necessary to have a set of red, green, and blue OLEDs. Efficient green and blue OLEDs are now available. Yet, there has been a lack of red OLEDs that exhibit both saturated emissions and high, stable luminescence quantum efficiency (Picciolo et al. (2001) Applied Phy. Lett . 78: 2378).
Currently, most red OLEDs contain dopant-containing layers made of red light emitting materials. See, e.g., Chen et al. (1997) Macromol. Symp . 125: 1; and Zhang et al. (2001) Chem. Mater . 13: 1565; and Picciolo et al. (2001) Appl. Phys. Lett . 78: 2378. The red light emitting materials can be polar, such as electron donor-substituted pyran compounds (Tang et al. (1989) Appl. Phys. Lett . 65: 3610; Zhang et al. (2001) Chem. Mater . 13: 1565; and Chen et al. (2001) J. Phys. D: Appl. Phys . 34: 30). They can also be extensively π-conjugated, such as porphyrin compounds (Burrows et al. (1996) Appl. Phys. Lett . 69: 2959; Morgado et al. (2001) J. Mater. Chem . 11: 278; and Kwong et al. (2000) Adv. Mater . 12: 1134). These materials have a tendency towards crystallization, and thus, are either weakly emissive or not emissive in solid state. Further, dopant-containing OLEDs are not favored in mass production.
SUMMARY
This invention relates to compounds that are useful, among others, as red light emitting materials for red OLEDs.
In one aspect, this invention features a compound having the formula:
X is O or NR 1 ; and each of Y and Z, independently, is
(referred to as Ar 1 NR 2 R 3 ; Ar 1 NR 4 ; or Ar 1 Ar 2 N hereinafter); in which each of R 1 , R 2 , R 3 , and R 4 , independently, is alkyl, cyclyl, heterocyclyl, aralkyl, aryl, or heteroaryl; Ar 1 is aralkyl, aryl, or heteroaryl; and Ar 2 is cyclyl, heterocyclyl, aralkyl, aryl, or heteroaryl; or Ar 1 and Ar 2 taken together is heterocyclyl, aralkyl, or heteroaryl.
A subset of the above-described compounds are those in which X is NR 1 . Embodiments include compounds in which Y and Z, independently, is Ar 1 NR 2 R 3 . Examples of Ar 1 include, but are not limited to, phenyl, furyl, thienyl, fluorenyl, 9,9′-R,R-substituted fluorenyl [each of the Rs, independently, is aryl (e.g., phenyl or 4-tolyl), or C 1 ˜C 6 alkyl], and [9,9′]spirobifluorenyl. Representative compounds are:
In each of the above structures, the two R 2 's (or the two R 3 's) can be the same or different. The same rule applies to other similar situations. Each of R 2 and R 3 , independently, can be phenyl or naphthyl; and R 1 can be CH 3 . Additional examples of R 2 and R 3 include, but are not limited to, biphenyl, terphenyl, anthracenyl, acenaphyl, perylenyl, pyrenyl, petacenyl, [9,9′]spirobifluorenyl, 9,9′-diarylfluorenyl, 9,9′-dialkylfluorenyl, and 9,9′-alkylarylfluorenyl; in which aryl represents phenyl, naphthyl, anthracenyl, pyrenyl, petacenyl, tolyl, or anisolyl, and alkyl represents methyl, ethyl, propyl, or butyl.
In other embodiments, each of Y and Z, independently, is Ar 1 NR 4 . Ar 1 can be carbazolyl or indolyl. Representative compounds are:
In still other embodiments, each of Y and Z, independently, is Ar 1 Ar 2 N. Ar 1 and Ar 2 taken together can be pyrido-quinoline. A representative compound is:
Another set of the compounds of this invention are those in which X is O. In these compounds, each of Y and Z, independently, can be Ar 1 NR 2 R 3 and Ar 1 can be phenyl, furyl, thienyl, fluorenyl, 9,9′-R,R-substituted fluorenyl [each of the Rs, independenly, is aryl (e.g., phenyl or 4-tolyl), or C 1 ˜C 6 alkyl], or [9,9′]spirobifluorenyl. Each of Y and Z, independently, also can be Ar 1 NR 4 or Ar 1 Ar 2 N, and Ar 1 can be carbazolyl or indolyl, or Ar 1 and Ar 2 taken together can be pyrido-quinoline. Representative compounds are:
Alkyl, cyclyl, heterocyclyl, aralkyl (e.g., fluorenyl or carbazolyl), aryl (e.g., phenyl), or heteroaryl (e.g., furyl, thienyl, or indolyl) mentioned above refers to both substituted and unsubstituted moieties. The term “substituted,” in turn, refers to one or more substituents (which may be the same or different), each replacing a hydrogen atom. Examples of substituents include, but are not limited to, halogen, amino, alkylamino, arylamino, dialkylamino, diarylamino, hydroxyl, mercapto, sulfonyl, cyano, nitro, C 1 ˜C 3 , alkyl, C 1 ˜C 6 alkenyl, C 1 ˜C 6 alkoxy, aryl, heteroaryl, aryloxy, cyclyl, or heterocyclyl; wherein alkyl, alkenyl, alkoxy, aryl, and heteroaryl are optionally substituted with C 1 ˜C 6 alkyl, halogen, amino, alkylamino, arylamino, dialkylamino, diarylamino, hydroxyl, mercapto, cyano, or nitro.
The term “aralkyl” refers to a moiety in which an alkyl hydrogen atom is replaced by an aryl group. Examples of aralkyl moieties include fluorenyl, carbazolyl, and 9,9′-substituted fluorenyl, such as [9,9′]spirobifluorenyl, 9,9′-diarylfluorenyl, 9,9′-dialkylfluorenyl, and 9,9′-alkylarylfluorenyl; in which aryl represents phenyl, naphthyl, anthracenyl, pyrenyl, petacenyl, tolyl, or anisolyl, and alkyl represents methyl, ethyl, propyl, or butyl.
The term “aryl” refers to a hydrocarbon ring system having at least one aromatic ring. Examples of aryl moieties include, but are not limited to, phenyl, naphthyl, anthracenyl, perylenyl, and pyrenyl.
The term “heteroaryl” refers to a hydrocarbon ring system having at least one aromatic ring which contains at least one heteroatom such as O, N, or S. Examples of heteroaryl moieties include, but are not limited to, pyridinyl, carbazolyl, and indolyl.
The terms “cyclyl” and “heterocyclyl” refer to partially and fully saturated mono-, bi-, or tri-cyclic rings having from 4 to 14 ring atoms. A heterocyclyl ring contains one or more heteroatoms. Exemplary cyclyl and heterocyclyl rings are cycylohexane, piperidine, piperazine, morpholine, thiomorpholine, and 1,4-oxazepane.
The compounds described above include the compounds themselves, as well as their salts, if applicable. The salts, for example, can be formed via interactions between a positively charged substitutent (e.g., amino) on a compound and an anion. Suitable anions include, but are not limited to, chloride, bromide, iodide, sulfate, nitrate, phosphate, citrate, methanesulfonate, trifluoroacetate, and acetate. Likewise, a negatively charged substitutent (e.g., carboxylate) on a compound can form a salt with a cation. Suitable cations include, but are not limited to, sodium ion, potassium ion, magnesium ion, and ammonium cation such as tetramethylammonium ion. In addition, some of the compounds have one or more asymmetric centers. Such compounds can occur as racemates, tautomers, enantiomers, and diastereometers.
One exemplary compound of this invention is N-methyl-bis(4-(1-naphthylphenylamino)phenyl)maleimide:
In another aspect, this invention features a red light emitting electro-luminescence device that is made with one or more of the compounds described above. The device includes an anode layer, a hole transporting layer, a light emitting layer that includes the compounds of this invention, an electron transporting layer, and a cathode layer. The anode, the hole transporting layer, the light emitting layer, the electron transporting layer, and the cathode are disposed in the above order. The hole transporting layer and the light emitting layer can be of the same layer. In other words, a layer, that sandwiches between the anode layer and the electron transporting layer, functions as both a hole transporting layer and a light emitting layer.
Other features, objects, and advantages of the invention will be apparent from the description and from the claims.
DETAILED DESCRIPTION
Within the scope of this invention are novel compounds and red light emitting electro-luminescence devices that contain such compounds.
The compounds of this invention can be prepared by methods well known to a skilled person in the art. For example, shown below is a scheme that depicts a synthetic route. In this scheme, Ar 1 , R 1 , R 2 , and R 3 are as defined in Summary.
As shown in the above scheme, a compound of this invention can be prepared with a cyanomethyl-bromoaryl compound as a starting material. More specifically, a cyanomethyl-bromoaryl compound is oxidized with iodine and hydrolyzed with an acid, followed by alkylation with a R 1 -halide and reaction with a R 2 , R 3 -substituted amine in the presence of palladium to form a desired product. If an asymmetrical compound of this invention is desired, two different cyanomethyl-bromoaryl compounds or two different R 2 , R 3 -substituted amines can be used.
In another example, as shown below, a cyanomethyl-substituted compound can be oxidized with an oxidizing agent, hydrolyzed with an acid, and alkylated with a R 1 -halide to form another compound of this invention. Further hydrolysis in alkali alchoholic solution can generate anhydride derivatives. In this scheme, Ar 1 , Ar 2 , and R 1 are as defined in Summary.
The chemicals used in the above-described synthetic routes may include, for example, solvents, reagents, catalysts, protecting group and deprotecting group reagents. The methods described above may also additionally include steps, either before or after the steps described specifically herein, to add or remove suitable protecting groups in order to ultimately allow synthesis of the compound of this invention. In addition, various synthetic steps may be performed in an alternate sequence or order to give a desired compound. Synthetic chemistry transformations and protecting group methodologies (protection and deprotection) useful in synthesizing applicable the claimed compounds are known in the art and include, for example, those described in R. Larock, Comprehensive Organic Transformations , VCH Publishers (1989); T. W. Greene and P. G. M. Wuts, Protective Groups in Organic Synthesis , 2d. Ed., John Wiley and Sons (1991); L. Fieser and M. Fieser, Fieser and Fieser's Reagents for Organic Synthesis , John Wiley and Sons (1994); and L. Paquette, ed., Encyclopedia of Reagents for Organic Synthesis , John Wiley and Sons (1995) and subsequent editions thereof.
A compound of this invention thus synthesized can be further purified by a method such as column chromatography, high pressure liquid chromatography, recrystallization, or sublimation.
One or more compounds of the invention can be used as a red light emitting material in an electro-luminescence device.
Typically, an electro-luminescence device is either a two- or a three-layer structured device. A two-layer structured device can include a hole transporting layer and an electron transporting layer, sandwiched between two layers of electrodes. Either the hole transporting layer or the electron transporting layer can function as a luminescent layer, which emits lights (Tang et al., (1989) J. Appl. Phys . 65: 3610). Generally, an anode layer, a hole transporting layer, an electron transport layer, and a cathode layer are deposited sequentially in the above order. The anode layer can be formed on a substrate, such as a glass. A three-layer structured device can include a hole transporting layer, a luminescent layer (i.e., light emitting layer), and an electron transporting layer, sandwiched between two layers of electrodes. More specifically, an anode layer, a hole transporting layer, a luminescent layer, an electron transport layer, and a cathode layer are deposited sequentially in the above order. The luminescent layer can be another hole transporting, another electron transporting layer, or a hole blocking layer. Optionally, the electro-luminescence device can include a dopant-containing layer, which can be an electron transporting layer or a luminescent layer.
Each of the above mentioned layers can be made of various materials, as described in, for example, U.S. Pat. No. 5,698,740. More specifically, a substrate can be made of glass; an anode layer can be a film of a transparent electroconductive material, e.g., indium tin oxide (ITO); a hole transporting layer can be made of 4,4′-bis[N-(1-naphthyl)-N-phenyl-amino]-biphenyl; an optional hole blocking layer can be made of 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP); an electron transporting layer can be made of 1,3,5-tris(N-phenylbenzimidazol-2-yl)benzene (TPBI); and a cathode layer can be made of a metal film, e.g., an alloy of magnesium and silver.
The fabrication of an electro-luminescence device has been described in, for example, Tang & VanSlyke (1987) Appl. Phys. Lett . 51: 913; Tang et al., (1989) J. Appl. Phys . 65: 3610, or Kido & Lizumi (1997) Chem. Lett . 963. More specifically, each layer may be formed by any film forming method such as vacuum deposition. See U.S. Pat. No. 5,698,740.
This invention features a device containing a light emitting layer that is made of one of the novel compounds described above. As an example, the device includes an anode layer, a hole transporting/light emitting layer that includes the compounds of this invention; an electron transporting layer; and a cathode layer. The anode, the hole transporting/light emitting layer, the electron transporting layer, and the cathode are disposed in the above order. Unexpectedly, this device is capable of emitting red light efficiently.
The specific example below is to be construed as merely illustrative, and not limitative of the remainder of the disclosure in any way whatsoever. Without further elaboration, it is believed that one skilled in the art can, based on the description herein, utilize the present invention to its fullest extent. All publications, including patents, cited herein are hereby incorporated by reference in their entirety.
Synthesis and Characterization of N-methyl-bis(4-(1-naphthylphenylamino)phenyl)maleimide (NPAMLI)
NPAMLI was prepared as follows:
More specifically, 4-bromobenzyl cyanide was oxidized with iodine and hydrolyzed with 3% HCl (aq)/THF to form bis(4-bromophenyl)maleonitrile (40˜50%). See Cook & Linstead (1937) J. Chem. Soc . 929. Bis(4-bromophenyl)maleonitrile thus obtained was alkylated with KotBu/CH 3 I to afford N-methyl-bis(4-bromophenyl)maleimide (86%). NPAMLI was prepared by palladium catalyzed amination of N-methyl-bis(4-bromophenyl)maleimide (71%), followed by column chromatography and sublimation purification. The synthetic data of the synthesized compounds are listed below:
Bis(4-bromophenyl)maleimide: 1 H NMR (400 MHz, CDCl 3 ): δ [ppm]. 7.51 (d, 4H, J=8.7 Hz), 7.49 (s, 1H), 7.33 (d, 4H, J=8.7 Hz). 13 C{ 1 H} NMR (100 MHz, CDCl 3 ): δ [ppm] 169.4, 136.0, 132.2, 131.3, 126.9, 125.1. FAB-MS: calcd MW, 407.06, m/e=408 (M + +1).
N-Methyl-bis(4-bromophenyl)maleimide: 1 H NMR (400 MHz, CDCl 3 ): δ [ppm] 7.50 (d, 4H, J=8.6 Hz), 7.33 (d, 4H, J=8.6 Hz), 3.13 (s, 3H). 13 C{ 1 H} NMR (100 MHz, CDCl 3 ): δ [ppm] 170.2, 135.5, 132.1, 131.3, 127.2, 124.8, 24.4. FAB-MS: calcd MW, 421.08, m/e=422 (M + +1).
N-Methyl-bis(4-(1-naphthylphenylamino)phenyl)maleimide (NPAMLI): Data of optical, electrochemical, and thermal properties of NPAMLI are summarized in Table 1. 1 H NMR (400 MHz, CDCl 3 ): δ [ppm] 7.91 (d, 2H, J=8.2 Hz), 7.83 (d, 2H, J=8.3 Hz), 7.78 (d, 2H, J=8.5 Hz), 7.52 (t, 2H, J=11.9 Hz), 7.36-7.42 (m, 4H), 7.20-7.25 (m, 6H), 6.94-7.06 (m, 10H), 6.54-6.59 (m, 4H), 3.09 (s, 3H) 13 C{ 1 H} NMR (100 MHz, CDCl 3 ): δ [ppm] 171.9, 149.9, 147.0, 142.9, 136.1, 133.6, 131.7, 131.4, 129.8, 129.0, 128.1, 127.8, 126.9, 126.8, 124.4, 124.3, 124.0, 121.1, 118.7, 118.7, 24.4. FAB-MS: calcd MW, 697.27, m/e=697 (M + ). Anal. Found (calcd) for C 49 H 35 N 3 O 2 : C, 84.21 (84.34), H, 5.04 (5.06), N, 5.99 (6.02).
Optical, electrochemical, and thermal properties of NPAMLI were also determined. NPAMLI was dissolved in deoxygenated dry dichloromethane, containing 0.1 M tetrabutylammonium perchlorate as electrolyte and a platinum working electrode, as well as a saturated Ag/AgNO 3 reference electrode. Ferrocene was used for potential calibration (all reported potentials are references against ferrocene/ferrocenium, FOC) and (or reversibility criteria. Nile red (Φ f =0.68 in 1,4-dioxane) (Sarkar et al. (1994) Langmuir 10: 326 was used as the standard for the fluorescence quantum yield determination. Fluorescence and absorption spectra were recorded by fluorescence spectrophotometer (Hitachi F-450) and absorption spectrophotometer (Hewlett-Packard 8453), respectively. Glass transition temperature (T g ) and thermal decomposition temperature (T d ) of NPAMLI were determined by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) using a Perkin-Elmer DSC-6 and TGA-7 analyzer systems, respectively. Both thermal analyses were performed with scanning (both heating and cooling) rate at 10 deg/min under nitrogen atmosphere. The temperatures were recorded on the intercept of the slope of thermogram changes (endothermic, exothermic, or weight loss) and the leading baseline as the estimation for on-set T g and T d . Redox potentials of NPAMLI were determined by cyclic voltammetry (CV) using Electochemical Analyzer BAS 100B with scanning rate at 100 mV/s.
As shown in Table 1, NPAMLI has a fluorescence quantum yield (Φ f ) of 21%, in 1,4-dioxane, which is almost two-folds of that of DCM (i.e., 11%), a commercially available laser dye and red dopant for red OLEDs (Tang et al. (1989) Appl. Phys. Lett . 65: 3610). Further, NPAMLI has a relatively wide full-width at half-maximum (fwhm˜94 mn) of emission bands. Due to its long wavelength of emission, nearly half of emission bands (either of PL or EL spectra) locate outside the long wavelength limit of the human vision.
TABLE 1
Optical, electrochemical, and thermal properties of NPAMLI.
Φ f
λ max abs
λ max em
(nm) [a]
E red
E oxd
T g
T d
(%)
(nm) [a]
Solution
Solid film
(V vs FOC)
(° C.)
(° C.)
21
501
683
651
−1.68
+0.53
122
419
[a] Samples were dissolved in chloroform when spectra were recorded. Solid films were prepared by spin-casting from chloroform solution and then vacuum-dried.
Unexpectedly, NPAMLI showed an amorphous feature. More specifically, it is a fluorophore having a donor (two arylamines) and acceptor (imide), and does not tend to crystallization in solid state. DSC thermograms (>400° C.) of NPAMLI showed that a weak endothermic step-transition was around 120° C., indicating the glass phase transition, and no crystallization or melting was observed. The glass phase of NPAMLI was relatively stable since the endothermic step-transition was still observed even after the sample was repeated heating and cooling. With this amorphous feature, NPAMLI was able to be used as a nondoping red light emitting material with weak or no concentration quenching effect.
It was also unexpected that NPAMLI was electrochemically stable. Cyclic voltamograms showed NPAMLI's redox process involving one electroreduction and one electrooxidation, both of which were apparently reversible under CV conditions. After quantitation of redox signals on CV, it was concluded that the redox process involved one-electron reduction and two-electron oxidation per molecule of NPAMLI, which indicated that two arylamines are electronically independent and are electrooxidized simultaneously. With this feature, NPAMLI was able to be used as a hole transporting material in addition to a red light emitting material. Further, NPAMLI is thermally robust. Its T d is about 420° C. estimated by TGA.
Fabrication of a Device Including NPAMLI as a Red Light Emitting Material and a Hole-transporting Material
A trilayer device ITO/NPAMLI/BCP/TPBI/Mg:Ag was fabricated by thermal deposition in a vacuum chamber (ULVAC Cryogenics at a chamber pressure of 10 −6 Torr). The substrate was an ITO-coated glass with a sheer resistance of <50 Ω/sq. ITO cleaning included a routine chemical cleaning using detergent and alcohol in sequence, followed by oxygen plasma cleaning. Sequential evaporation of NPAMLI as a hole transporting layer (500 Å) as well as red light emitting layer, BCP as a hole blocking layer (100 Å), and TPBI as an electron transporting layer (400 Å) was performed. A cathode Mg 0 9 Ag 0 1 alloy was then deposited (50 nm) by co-evaporation and followed by a thick silver capping layer.
The just-obtained device was tested for current density (I)-voltage (V)-luminance (L) characteristrics, EL spectra of the device and PL spectra of NPAMLI, current density dependency of external quantum efficiency, and a CIE (Commission Internationale de l'Eclairage) 1931 color chromaticity diagram of the device. An EL spectrum with an emission maximum of 650 nm was observed, which was almost superimposable on a PL spectrum of NPAMLI. A weak but discernable emission band (around 380 nm) was also observed due to TPBI emission (Tao et al. (2000) Appl. Phys. Lett . 77: 933), even though a hole blocking layer of BCP was added to prevent the emission of TPBI. When the EL spectrum was converted into a chromaticity coordinates on a CIE 1931 diagram, an indication of red light emitting from the device was obtained (x=0.66, y=0.32), which was comparable with (x=0.64, y=0.33) of National Television System Committee (NTSC) standard red color. This device had the maximum luminance of near 8,000 cd/m 2 at 15 V; and luminance of more than 300 cd/m 2 at low current density of 20 mA/cm 2 . It had the maximum external quantum efficiency of 2.4% (corresponding to 1.5 cd/A or 0.9 lm/W) at about 20 mA/cm 2 . The performance of the device is comparable with or better than known red OLEDs, which all include a red dopant-containing layer. As the other red OLEDs, the device showed steady decline in efficiency with increasing current density and barely maintained at 1% of the external quantum efficiency at maximum luminance. See, e.g., Picciolo et al. (2000) Appl. Phys. Lett . 78: 2378; and Young et al. (2002) Appl. Phys. Lett . 80: 874. Unexpectedly, without using a dopant-containing layer, this device is able to emit red light efficiently, and is easily fabricated.
Other Embodiments
All of the features disclosed in this specification may be combined in any combination. Each feature disclosed in this specification may be replaced by an alternative feature serving the same, equivalent, or similar purpose. Thus, unless expressly stated otherwise, each feature disclosed is only an example of a generic series of equivalent or similar features.
From the above description, one skilled in the art can easily ascertain the essential characteristics of the present invention, and without departing from the spirit and scope thereof, can make various changes and modifications of the invention to adapt it to various usages and conditions. Accordingly, other embodiments are also within the scope of the following claims.
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This invention features a compound having the formula:
X is O or NR 1 ; and each of Y and Z, independently, is
in which each of R 1 , R 2 , R 3 , and R 4 , independently, is alkyl, cyclyl, heterocyclyl, aralkyl, aryl, or heteroaryl; Ar 1 is aralkyl, aryl, or heteroaryl; and Ar 2 is cyclyl, heterocyclyl, aralkyl, aryl, or heteroaryl; or Ar 1 and Ar 2 taken together is heterocyclyl, aralkyl, or heteroaryl. This compound can be used as a red light emitting material in an electro-luminescence device.
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CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation-in-part (CIP) of U.S. application Ser. No. 09/031,756 filed Feb. 27, 1998, now abandoned, which claimed priority from U.S. provisional application Serial No. 60/039,674 filed Feb. 28, 1997.
BACKGROUND OF THE INVENTION
The present invention relates to electrical stimulation of the expiratory muscles to produce cough in human patients and other mammals with spinal cord injuries resulting in paralysis of their expiratory muscles. The invention will allow human patients with such spinal cord injuries to cough periodically or as needed to prevent the occurrence of respiratory infections which have heretofore been a frequent cause of illness and even death among this patient population.
Human patients with spinal cord injury often have paralysis of a major portion or virtually all of their expiratory muscles and, therefore, lack a normal cough mechanism. As a consequence, many of these patients suffer from a markedly reduced ability to clear airway secretions. This factor contributes to the development of recurrent respiratory tract infections, a major cause of morbidity and mortality in this patient population.
Although mechanical methods exist which can increase peak expiratory air flow to improve cough effort, the degree of improvement with these methods is small. For example, the abdominal push assist maneuver involves assisting a patient's expiratory effort by applying pressure with both hands to the upper abdomen in a posterior and cephalad direction. If abdominal pressure is applied following spontaneous inspiration and glottic closure, an adequate cough pattern may be achievable. This procedure has been found to result in modest increments in peak expiratory flow (in the range of approximately 14%) over that achieved without assist and no change in total volume during the cough.
Another prior mechanical technique is mechanical insufflation-exsufflation. This is carried out by the application of positive pressure to the patient's airway followed by rapid decompression, which results in the generation of high expiratory airflows. This technique may also be effective in removing foreign bodies from the patient's airway.
Although these prior techniques may be generally effective, a need has been found for more effective methods. A major disadvantage of these prior techniques is that they are dependent upon trained personnel and provider-patient coordination. Consequently, these methods are costly and labor intensive.
Heretofore, no effective method and apparatus have been found for selectively electrically activating expiratory muscles of a human patient or other mammal by stimulation of the spinal cord roots to produce a functionally effective cough. The only known prior method for electrical stimulation of the abdominal muscles is via surface electrodes over the anterior abdominal wall. This prior technique does not result in complete activation of the abdominal muscles which creates only submaximal cough efforts and requires high stimulus intensities.
Accordingly, it is deemed desirable to develop methods and apparatus which overcome the foregoing deficiencies and others while providing better and more advantageous overall results.
SUMMARY OF THE INVENTION
In accordance with the present invention, a method and apparatus are provided for electrical stimulation of the expiratory muscles in a human or other mammal to produce cough in patients with spinal cord injuries resulting in paralysis of their expiratory muscles.
In accordance with a first aspect of the present invention, a method of electrically activating expiratory muscles of a human patient or other mammal includes positioning a first epidural electrode at a first location on the dorsal surface of a spinal cord of a patient and a second epidural electrode at a second location on the dorsal surface of the patient's spinal cord. Electrical stimulation pulses are selectively passed to the first and second epidural electrodes to activate expiratory muscles of the patient to produce cough.
Preferably, the first epidural electrode is positioned on the spinal cord dorsal surface in the region of the T 9 -T 10 spinal root level, while the second epidural electrode is positioned in the region of the lower thoracic spinal root. Most preferably, the second electrode is positioned on the dorsal surface of the spinal cord in the region of the T 12 -L 1 spinal cord level.
One advantage of the present invention is found in the provision of an effective method and apparatus for selective electrical stimulation of the expiratory muscles to produce a cough in a human patient or other mammal having spinal cord injuries resulting in paralysis of the expiratory muscles.
Another advantage of the present invention is that it allows spinal cord injured patients to clear secretions more easily and thereby improve their lifestyle and reduce the morbidity and mortality due to respiratory complications.
Still another advantage of the present invention is that it provides for the optimal number of stimulation electrodes to produce the optimum contraction of the expiratory muscles.
Yet another advantage of the present invention is that it provides for optimal electrode placement for maximum expiratory pressure generation.
Still a further advantage of the present invention resides in its ability to provide a safe and effective means by which a normal and effective cough may be produced on demand without the need for the frequent presence of trained providers.
A yet further advantage of the present invention resides in the provision of a portable, battery-powered expiratory muscle stimulation apparatus that is able to travel with the patient in an easy and convenient manner.
Still further benefits and advantages of the present invention will become apparent to those of ordinary skill in the art upon reading and understanding the following detailed description of the preferred embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention may take form in various components and arrangements of components. The drawings are only for purposes of illustrating preferred embodiments and are not to be construed as limiting the invention.
FIG. 1 is a graph illustrating the effect of electrode placement in a mammal on airway pressure generation;
FIG. 2A is a graph illustrating the effects of stimulus amplitude on airway pressure;
FIG. 2B is a graph illustrating the effects of stimulus frequency on airway pressure;
FIG. 3 is a graph illustrating the effect of spinal cord stimulation, as indicated by arrows, on internal intercostal (IIC) and external oblique (EO) muscle lengths and airway pressure generation with deflation, at functional residual capacity (FRC) and at two levels of inflation;
FIG. 4 graphically illustrates mean generated airway pressures as a function of pre-contractile airways;
FIG. 5 is a graph illustrating the effects of spinal cord stimulation in a mammal on peak expiratory airflow at FRC and two levels of inflation;
FIG. 6 graphically illustrates mean peak expiratory airflows as a function of pre-contractile airway pressures;
FIG. 7 graphically illustrates mean changes in internal intercostal and external oblique muscle length with passive inflation and deflation (solid symbols) and during spinal cord stimulation (open symbols) over a wide range of lung volumes;
FIG. 8 illustrates that threshold values for the IIC (7 th -11 th spaces) for the upper portions of EO, RA and TA were near their minimum at the T 9 -T 10 spinal cord level;
FIG. 9 illustrates that threshold values of the compound action potential for the IO and lower portions of the EO and TA were near their minimum at the T 13 -L 1 spinal cord region (corresponding to T 12 -L 1 for humans);
FIG. 10 shows the mean contribution of various expiratory muscles to pressure generation from stimulation at different spinal root levels;
FIG. 11 shows mean airway pressure generation and contribution of the various expiratory muscles to pressure generation during stimulation applied to the T 9 -T 10 spinal root level plus the simultaneous application of current to another spinal root level;
FIG. 12 graphically illustrates the contrast between upper and lower thoracic spinal cord stimulation with respect to the effect of dorsal vs. ventral placement of the stimulation electrode;
FIG. 13 illustrates the synergistic effect on pressure generation resulting from optimal multiple electrode placement and simultaneous stimulation in accordance with the method of the present invention;
FIG. 14 illustrates the effects of epidural spinal cord stimulation during stimulation at T 9 /T 10 alone, T 13 /L 1 alone, and combined stimulation of both areas in accordance with the present invention wherein it can be seen that combined stimulation of both areas resulted in significantly greater changes in airway pressure compared to stimulation at either area alone;
FIG. 15 illustrates the effects of surface stimulation over the anterior abdominal wall on airway pressure generation with 2 and 4 electrodes before and after spinal root section (T 8 through L 2 ) wherein maximal electrical stimulation resulted in only small changes in airway pressure (root section had no effect on pressure generation); and,
FIG. 16 illustrates the effects of surface stimulation over the spinal roots posteriorly with 2 and 4 electrodes before and after spinal root section. Maximal surface stimulation over the spinal roots resulted in larger changes in airway pressure compared to surface stimulation over the anterior abdominal wall. Spinal root section resulted in a decrease in pressure generation indicating that spinal cord pathways contributed to the observed changes in airway pressure.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the drawings, the showings are for purposes of illustrating preferred embodiments of the invention only and are not for purposes of limiting the same. Prior to application of spinal cord stimulation on human patients, and in order to develop the methods and apparatus of the present invention, it was necessary to evaluate the effects of motor root activation in animal studies. In this manner, it was possible to explore the utility of electrical stimuli applied to the lower thoracic region of the spinal cord to generate large changes in intrathoracic pressure and expiratory airflow, characteristic of cough. Further, it was necessary to assess optimum electrode placement, stimulus paradigm, and pattern of respiratory muscle recruitment since determination of these heretofore unknown variables was required prior to any human trials. Since the capacity of the expiratory muscles to generate force is dependent upon their precontractile lengths, studies were performed both at functional residual capacity (FRC) and over a wide range of static airway pressures. Muscle length measurements were also made to assess the degree and extent of expiratory muscle activation.
Methods
Studies were performed on 15 adult mongrel dogs (mean weight: 17.9 kg±0.4). Animals were anesthetized with pentobarbital sodium at an initial dose of 30 mg/kg given intravenously. Subsequent doses of approximately 2-4 mg/kg were provided as needed. All animals underwent a cervical tracheostomy and placement of a large bore cuffed endotracheal tube (inner diameter 10 mm). Blood pressure was monitored via a cannula placed in the femoral artery; a separate cannula in the femoral vein was used to administer additional anesthetic. The level of anesthesia was monitored by the corneal reflex which was suppressed. Body temperature was kept at 38±0.50° C. with a homeothermic blanket (Harvard Apparatus). Sodium bicarbonate was administered, as needed, to maintain blood pH at 7.35±0.05. A quadripolar platinum-iridium stimulating electrode (Medtronic Model 3586; Medtronic Inc., Minneapolis, Minn.) was inserted epidurally and on the ventral surface of the spinal cord via a T 4 -T 5 laminectomy and then advanced caudally over the lower thoracic spinal cord. At this stage, a four-channel stimulator (Applied Neural Control Laboratory, Case Western Reserve University) was used for electrical stimulation. This stimulator provides a biphasic, pulse-width modulated impulse.
In seven animals, muscle length was measured with sonomicrometry. Pairs of piezoelectric crystals (Model 120, Triton Technology, San Diego, Calif.), spaced 5-12 mm apart and oriented along the long axes of muscle fibers, were sewn into the internal intercostal (IIC) (mid-axillary line) of the 9 th or 10 th intercostal space and external oblique (EO) muscles midway between the costal margin and pelvis. A small portion of the external intercostal and EO muscles were excised to provide access to the IIC muscles. Resting length was determined following hyperventilation induced apnea; changes in muscle length were expressed as a percentage of this value at FRC (percentage of resting length, % L R ).
Protocol
The effect of spinal cord stimulation (SCS) at different spinal cord levels was evaluated to determine optimal electrode placement. Also, the relationship between the stimulus parameters and airway pressure generation was determined. Changes in airway pressure during lower thoracic SCS were assessed following hyperventilation-induced apnea and airway occlusion. Electrical stimulation was applied at FRC and also over a wide range of lung volumes between approximately 0.3 liters below and 1.3 liters above FRC. Lung volume changes were produced by inflating and deflating the animal with a 2.0 liter volume syringe. A mean of 10±1 different volumes provided randomly were evaluated in each animal. These studies were performed in 15 animals.
After peak airway pressure was achieved consequent to spinal cord stimulation (SCS), the occlusion was released to assess expiratory airflow generation. This maneuver was also performed over a wide range of lung volumes. Studies were performed in 5 animals.
To assess the possibility of current spread more cephalad to activate the inspiratory intercostal muscles, spinal cord stimulation was performed before and after section of the parasternal muscles and also external intercostal muscles to the posterior axillary line from the 2 nd through 6 th interspaces. These studies were performed in 4 animals.
Data Analysis
Inflation and deflation produced a wide range of precontractile airway pressures between -14 and +35 cm H 2 O. Precontractile static airway pressures were plotted against generated airway pressure and peak expiratory airflows produced by spinal cord stimulation in each animal. Changes in muscle length were expressed as a percentage of resting length (% L R ) and were analyzed in similar fashion.
Mean changes (±SE) in airway pressure, airflow, and muscle length resulting from spinal cord stimulation at specific precontractile airway pressures were then determined by interpolation of curves obtained from individual animals. Statistical analyses were performed utilizing a one-way analysis of variance and Student's t-test. A p value of <0.05 was considered significant.
Results
The effects of spinal cord stimulation in the region of the lower thoracic spinal cord is provided in FIG. 1. As shown, electrical stimuli applied at spinal cord level T 9 -T 10 provided maximal changes in airway pressure generation. Stimulation above and below this region resulted in progressive reductions in airway pressure generation as the electrode was positioned more caudally or rostrally. Similar results were obtained in three other animals. In each subsequent animal, therefore, we sought to position the electrode in the T 9 -T 10 region; the precise final electrode location was determined by that position which resulted in maximum positive airway pressure generation. By visual inspection and palpation, electrical stimulation in this area produced a marked symmetric contraction of the abdominal muscles and intercostal muscles of the lower rib cage bilaterally. There was no muscle contraction of the limbs nor visible contraction of the upper rib cage muscles.
The effects of alterations in stimulus amplitude (0.1 msec pulse width) and frequency on airway pressure generation at FRC is shown for one animal in FIG. 2A. Increasing stimulus amplitude at a constant stimulus frequency (50 Hz) resulted in progressive increases in airway pressure generation until a plateau was reached at approximately 10-12 mA. Repeated stimulation at higher amplitudes resulted in no further increases in airway pressure. Increasing stimulus frequency, as shown in FIG. 2B (at supramaximal stimulus amplitude), resulted in progressive increases in airway pressure generation until a plateau was reached at 40-45 Hz. Again, repeated stimulation at higher frequencies resulted in approximately the same changes in airway pressure. Similar results were obtained in the three other animals. In each animal studied, supramaximal stimulus parameters were determined initially, and all subsequent portions of the study were performed with that stimulus paradigm.
The effects of supramaximal spinal cord stimulation at the T 9 -T 10 spinal cord level on airway pressure generation, and internal intercostal (IIC) and external oblique (EO) muscle length are shown for one animal in FIG. 3 (the lower arrows indicate the onset and duration of electrical stimulation; the upper arrows indicate the onset of inflation or deflation). At FRC, electrical stimulation resulted in a large positive deflection in airway pressure and marked shortening of both the IIC and EO muscles. With passive deflation, there was passive shortening of the IIC muscle and little change in EO muscle length. Subsequent electrical stimulation resulted in IIC and EO muscle shortening, similar to that which occurred at FRC, but a smaller increase in airway pressure. With passive inflation, both IIC and EO muscles lengthened; subsequent stimulation resulted in similar degrees of muscle shortening as that achieved at FRC and with deflation. As lung volume increased, however, airway pressure generation increased progressively.
The mean changes in airway pressure generation over a wide range of lung volumes is shown for one animal in FIG. 4. With increasing lung volume (expressed as the corresponding change in airway pressure), there were progressive increases in the magnitude of generated positive airway pressure according to a linear function (slope (s)=1.34±0.04). In all animals, the range of correlation coefficients (cc) was between 0.89 and 0.99 (mean=0.97±0.01). The mean generated airway pressure at a passive inflation pressure of +30 cm H 2 O was 82 cm H 2 O±7 SE, and in several animals exceeded 100 cm H 2 O. In more recent studies, airway pressures have exceeded 175 cm H 2 O.
During the performance of these studies, airway pressure generation was intermittently reassessed at FRC (5-7 times in each animal) to evaluate the reproducibility of the response and stability of the animal. The coefficient of variance was less than 10% in each animal.
Airway pressure generation was not significantly affected by parasternal and external intercostal muscle action. Mean airway pressure was 49 cm H 2 O±13 SE before and 45 cm H 2 O±10 SE after muscle section at FRC.
The effects of spinal cord stimulation on expiratory airflow generation are shown for one animal in FIG. 5 (the lower arrows indicate the onset and duration of electrical stimulation; the upper arrows indicate release of occlusion). Release of occlusion at FRC was associated with a peak flow rate of approximately 150 liters/minute. As lung volume was increased, spinal cord stimulation was associated with progressively greater peak airflow rates. The mean peak flows generated over a wide range of lung volumes are shown in FIG. 6. With increasing lung volume, there were progressive increases in peak airflow generation according to a linear function (slope=4.1±0.2).
The mean changes in muscle length as a result of passive inflation and deflation (solid symbols) are shown in the upper portion of FIG. 7. Both IIC and EO muscles shortened with passive deflation and lengthened progressively with increasing inflation in each animal. The magnitude of passive IIC lengthening at airway pressures of 20 and 30 cm H 2 O were significantly greater than that of EO (P<0.05). During supramaximal ventral root stimulation (open symbols), the IIC shortened to approximately 35-40% of resting length, while the EO shortened to approximately 20% of resting length (P<0.05). The degree of muscle shortening, however, did not vary significantly with lung volume for either muscle.
Discussion
It was apparent from the foregoing that a major portion of the expiratory muscle mass in mammals, including the abdominal muscles and the internal intercostal (IIC) muscles of the lower rib cage, can be activated reproducibly and in concert via lower thoracic spinal cord stimulation. The capacity of the expiratory muscles to produce changes in airway pressure and expiratory airflow varies markedly with lung volume; airway pressure and airflow generation are maximal at the highest inflation pressure and fall linearly with decreasing lung volume. Based upon the foregoing, it was determined that this electrical spinal cord stimulation technique can be a useful method of restoring cough in certain human patients with spinal cord injury and may also be a useful tool in assessing the mechanical properties of the expiratory muscles.
Mechanism of Muscle Activation
Initially, it was unclear exactly by which mechanisms the expiratory muscles were activated by the application of electrical stimuli in the region of the lower thoracic spinal cord. The mechanisms were thought to include: a) activation of spinal cord pathways and motoneurons, either directly or via spinal cord reflex pathways; b) direct activation of the ventral roots; or c) some combination of each of these pathways. Stimulation of descending motor tracts seemed unlikely, however, since activation of those tracts would be expected to produce a more generalized pattern of discharge and result in contraction of the lower limbs. It was determined that further studies were necessary to determine the specific path of current flow which results in expiratory muscle activation.
Patterns of Muscle Activation
Based upon previous experience with similar stimulus paradigms applied in the region of the upper thoracic spinal cord, electrical current spreads across several spinal segments both cephalad and caudal to the site of electrode placement. Since the electrode was positioned at the T 9 -T 10 spinal cord level in the present studies, we would expect current spread to activate roots as high as the T 6 spinal level and caudally to activate the lower thoracic spinal roots. Based upon this degree of current spread, this should result in activation of the intercostal muscles of the lower rib cage (T 7 -T 12 ) and the abdominal muscles (external and internal oblique, transversus abdominis and rectus abdominis) which are enervated by branches of the lower thoracic nerves.
Ideally, any technique to restore cough in humans and other mammals should result in activation of the expiratory muscles alone. Electrical current applied in the region of the lower thoracic spinal cord, however, provides a non-specific motor stimulus. The thoracic spinal nerves are mixed motor nerves enervating both inspiratory and expiratory muscles. While the internal intercostals of the lower rib cage (expiratory in action) were clearly activated, the external intercostal and levator costae muscles (inspiratory in action) of the lower rib cage were most likely stimulated, as well. It is unlikely, however, that external intercostal and levator costae activation resulted in any significant opposing action. In the lower rib cage, the external intercostals are very thin muscles and, in addition, do not encompass the entire interspace. The levator costae muscles are small flat spindle-shaped muscles located posteriorly. The internal intercostals (expiratory in function), on the other hand, are thick muscles over this region of the rib cage (approximately 3 mm) and encompass the entire space.
Current spread to the upper thoracic ventral roots (T 1 -T 6 ) would have resulted in activation of inspiratory muscles of the upper rib cage, and generation of negative swings in airway pressure. It is unlikely, however, that current was transmitted this far cephalad since section of the parasternal and external intercostal muscles had no significant effect on airway pressure generation. At lung volumes above FRC, activation of the inspiratory intercostals is of much less concern since the capacity of these muscles to produce a fall in airway pressure declines rapidly as lung volume increases (12).
Significant portions of the triangularis sterni (TS) muscle were clearly not activated since parasternal section had no effect on airway pressure generation and the TS muscle is also enervated by the same internal intercostal nerves. Previous studies suggest, however, that the abdominal muscles are the major force generators and, of these, the transversus abdominis is the most important. While length measurements of this latter muscle were not made (to minimize the degree of surgery), its activation is likely due to the pattern of current spread. During spontaneous cough induced by mechanical stimulation of the trachea, however, it has been demonstrated that the electrical activation of both the triangularis sterni and transversus abdominis increase substantially. It has also been found that the electrical activation of these muscles peaked simultaneously during cough.
Although the foregoing technique clearly did not result in activation of all the expiratory muscles, the portion of expiratory muscle mass being stimulated was maximally activated. This is evidenced by the fact that with increasing stimulus frequency and amplitude, a plateau in airway pressure generation was achieved. Furthermore, the stimulus frequency and amplitude/response curves are qualitatively similar to that observed with either phrenic nerve stimulation or inspiratory intercostal muscle stimulation.
This above-described technique therefore provides a method by which a major portion of the expiratory muscles of a human or other mammal can be activated in reproducible fashion by positioning a single electrode on the ventral surface of the spinal cord.
Muscle Length Changes
Both the internal intercostal (IIC) muscles and external oblique (EO) muscles lengthened progressively with inflation and shortened with deflation, consistent with the action of expiratory agonists. The degree of passive muscle length changes was consistent with previous observations. Previous studies have shown that the internal layer of abdominal muscles (transversus abdominis and internal oblique) demonstrated significantly greater passive lengthening with inflation than the external layer (external oblique and rectus abdominis muscles). Because the transversus is thought to be the major force generator, the greater passive changes in resting length may be responsible, to some extent, for the large difference in airway pressure change between high and low lung volumes.
The EO muscles shortened by 15-20% of resting length while the IIC muscle shortened 35-40% of resting length in response to spinal cord stimulation. The degree of EO shortening with stimulation is far greater than the degree of shortening observed (<5%) with expiratory threshold loading and hypercapnia (90 mmHg), but less than the approximately 40% shortening observed when this muscle was stimulated directly in isolation. The maximum degree of EO shortening during spinal cord stimulation may be less, however, when all of the expiratory muscles are contracting in concert. For example, the increase in intra-abdominal pressure caused by IIC and transversus abdominous muscle contractions may oppose shortening of the abdominal muscles.
The foregoing indicates the feasibility of spinal cord stimulation to produce cough. However, single electrode stimulation as described above has been found to be sub-optimal. In particular, while large positive airway pressures can be generated by spinal cord stimulation to restore cough in spinal cord injured human patients and other mammals, optimal electrode placement was not apparent from the foregoing and required an assessment of the pattern of electrical current spread during spinal cord stimulation.
Studies were performed in six anesthetized dogs to assess the pattern of expiratory muscle recruitment during spinal cord stimulation applied at different spinal cord levels. A multicontact stimulating electrode was positioned over the surface of the lower thoracic and upper lumbar spinal cord. Recording electrodes were placed in the upper and lower portions of the transversus abdominis (TA), external oblique (EO), internal obliques (IO), rectus abdominis (RA) and the internal intercostal muscles (IIC). Spinal cord stimulation was applied at each lead, in separate trials, with single shocks, 0.1-0.2 msec duration. The intensity of stimulation was adjusted to determine the threshold for development of the compound action potential (CAP) at each electrode lead. The threshold for activation of each muscle formed parabolas with minimum values at specific spinal root levels. With reference to FIG. 8, it is shown that at the T 9 -T 10 spinal cord level (which results in maximum positive pressure generation), threshold values for the IIC (7 th -11 th spaces) upper portions of EO, RA and TA were near their minimums. The slopes of the parabolas were relatively steep indicating that the threshold for muscle activation increases rapidly at more cephalad and caudal sites. Threshold values of the CAP for the IO and lower portions of the EO and TA were near their minimum at the T 13 -L 1 spinal cord region (FIG. 9). At the T 9 -T 10 spinal cord level, threshold values for activating these latter muscles was high (>25 mA).
The results indicated that very high current levels at the T 9 -T 10 level (>40 mA) or the use of more than one electrode would be necessary to achieve uniform expiratory muscle activation as is required for effective cough via electrical spinal cord stimulation.
However, it was also necessary to determine the mechanical contribution of the individual expiratory muscles to pressure generation during spinal cord stimulation. To do so, five anesthetized dogs were utilized. Spinal cord stimulation (15 mA) was applied at several different levels using a midline multicontact electrode before and after sectioning different groups of respiratory muscles. Airway pressure (P) was monitored following tracheal occlusion. Mean contribution of various expiratory muscles to pressure generation by stimulation at different spinal root levels is shown in FIG. 10. Electrical stimulation at the T 9 -T 10 spinal cord level resulted in maximum P of 53 cm H 2 O±5 SE. Ablation of the obliques (external and internal, OB), rectus abdominis (RA), transversus abdominis (TA) and internal intercostals of the lower rib cage (IIC) resulted in 51±3, 5±2, 26±3, and 13%±1 SE reductions in pressure generation, respectively. Stimulation at other sites resulted in significantly smaller P. During stimulation at T 7 , P was 27 cm H 2 O±6 SE (p<0.05) and ablation of OB, RA, TA and IIC resulted in 41±13, 4±2, 12±9, and 43%±12 SE reductions in pressure generation. During spinal cord stimulation at L 1 , P was 22±5 cm H 2 O (p<0.05 compared to T9) and ablation of OB, RA, TA, and IIC resulted in 50±5, 3±1, 38±5, and 6%±3 SE reductions in P.
FIG. 11 illustrates mean airway pressure generation and the contribution of the various expiratory muscles to pressure generation during stimulation applied to the T 9 -T 10 spinal root level plus the simultaneous application of current to another spinal root level. When simultaneous stimulation was applied with a second electrode in the same vicinity as the first (T 9 -T 10 ), there were only small increments in pressure production (NS). However, the simultaneous application of current with a second electrode in the region of the lower thoracic spinal root (T 13 -L 1 ) resulted in significant increases in pressure production (p<0.05). This increase in pressure production with the two electrode system resulted largely from increased contributions from both the obliques and transversus muscles. Those skilled in the art will recognize that human patients do not have a T 13 -L 1 spinal cord level, but that the human spinal cord level of T 12 -L 1 corresponds thereto. In human patients and other mammals that are particularly large and have a longer spinal cord, a third epidural electrode is advantageously used to counteract the effects of stimulation current dissipation over longer distances. Most preferably, the third electrode is positioned on the dorsal surface of the spinal cord in the region between the aforementioned first and second electrodes. Furthermore, it has been found most desirable to substantially simultaneously pass electrical stimulation pulses to all the electrodes at a frequency in the range of approximately 20 Hz-50 Hz wherein each pulse has an amplitude in the range of approximately 10 mA-40 mA.
The foregoing indicates that the external and internal obliques (OB) and the transversus abdominis (TA) make the largest contribution to airway pressure (P) during spinal cord stimulation at T 9 -T 10 and the reduction of P at other sites was secondary to reductions in expiratory agonist activation rather than activation of antagonists. This data, coupled with recent electromyographic (emg) studies indicates that upper abdominal and internal intercostals of the lower rib cage (IIC) stimulation make a larger contribution to pressure generation compared to lower abdominal muscle stimulation.
In order to apply the foregoing to human patients and other mammals, it was deemed necessary and desirable to determine the particular mechanism of significant expiratory pressure generation (cough effort) by these electrical stimulation methods. Therefore, it was necessary to study the mechanism of expiratory muscle activation via lower thoracic spinal cord stimulation (T 9 -T 10 region).
Using seven anesthetized dogs, airway pressure (P) changes during stimulation against an occluded airway were used and an index of the degree of expiratory muscle activation. With reference now also to FIG. 12, in contrast to upper thoracic spinal cord stimulation, dorsal placement of the stimulation electrode resulted in greater changes in P compared to ventral placement over a wide range of stimulus amplitudes. Dorsal spinal cord stimulation following section of all spinal roots between T 8 and L 2 resulted in a marked fall in P to 15 cm H 2 O±1 SE (p<0.01).
In other studies with the spinal roots intact, the effects of transection of the spinal cord at the T 11 level were assessed. Spinal cord section resulted in large decrements in P from 54 cm H2O±2 SE to 21 cm H2O±2 SE. From this, it was determined that stimulation of the descending pathways localized near the dorsal surface of the spinal cord is an important mechanism of expiratory muscle activation via lower thoracic spinal cord stimulation.
In light of the foregoing, it was deemed necessary and desirable to study further the mechanism of airway pressure generation during lower thoracic spinal cord stimulation, in particular, the effect of synchronous activation of the musculature of both the upper and lower portions of the abdominal wall. In seven anesthetized dogs, spinal cord stimulation was applied with one electrode at the T 9 -T 10 (upper) and another at the T 13 -L 1 (lower) region of the spinal cord. During separate stimulation of the upper and lower electrodes, P was 55 cm H 2 O±2 SE and 16 cm H 2 O±3 SE, respectively. As is shown in FIG. 13, combined stimulation generated pressures that were larger than those produced by T 9 -T 10 stimulation alone, indicating that T 9 -T 10 stimulation alone is suboptimal.
To eliminate the potential influence of spinal cord pathways and assess the effects of local motor root activation alone, spinal cord stimulation was applied following section of the spinal roots (T 8 -L 2 ). During separate stimulation at T 9 -T 10 and T 13 -L 1 , alone, P was 12±2 and 15±3 cm H 2 O, respectively. However, combined stimulation via the upper and lower electrodes together resulted in P=50±2 cm H 2 O, a marked synergistic effect (P<0.05; compared to the arithmetic sum). In addition, following the application of an inelastic band around the lower portion of the abdominal wall, P during upper motor root stimulation alone increased to 22±3 cm H 2 O (P<0.05).
From this, it can be seen that: a) contraction of one portion of the abdominal wall alone results in dissipation of P via expansion of the non-contracted part of the abdominal wall, and b) synchronous activation of both the upper and lower portions of the abdominal wall is necessary to produce substantial changes in P. Furthermore, since P during T 9 -T 10 stimulation was much greater in the intact compared to the denervated state and also similar to combined stimulation by the upper and lower electrodes, it is shown that stimulation at the T 9 -T 10 region results in activation of the lower portion of the abdominal wall via spinal cord pathways.
To further explore and demonstrate the advantages of the foregoing methods over non-invasive stimulation methods in restoring cough in spinal cord injured patients, a comparison of the foregoing spinal cord stimulation methods with surface stimulation of the abdominal wall (SA) and also electrical surface stimulation of the spinal nerves (SN) was carried out.
In five anesthetized supine dogs, changes in airway pressure (P) were monitored during airway occlusion and supramaximal stimulation applied during: a) spinal cord stimulation (SCS) at T 9 /T 10 , T 13 /L 1 , and combined stimulation at both sites (FIG. 14); b) electrical stimulation applied over the surface of the anterior abdominal wall (SA) with 2 electrodes positioned in the anterior axillary line bilaterally 2-3 cm below the costal margin and 2 electrodes positioned in the anterior axillary line 1 cm above the pelvic brim, and combined stimulation at both sites (FIG. 15); and, c) electrical surface stimulation of the spinal nerves (SN) with 2 electrodes positioned between the 9 th and 10 th ribs posteriorly just lateral to the midline and 2 electrodes positioned over the T 13 /L 1 spinal roots just lateral to the midline, and combined stimulation at both sites (FIG. 16). Electrical stimulation was repeated following spinal root section (T 8 through L 2 ) during SA and SN. During SCS, electrical stimulation resulted in P=60 cm H 2 O±3 SE, 19 cm H 2 O±4 SE, and 77 cm H 2 O±3 SE during stimulation at T 9 /T 10 , T 13 /L 1 , and combined stimulation at these sites, respectively. During SA, electrical stimulation resulted in P=14 cm H 2 O±1 SE, 10 cm H 2 O±1 SE, and 23 cm H 2 O±1 SE during stimulation of the upper portion, lower portion, and combined stimulation at both sites, respectively. Spinal root section during SA had no effect on changes in P. During SN, electrical stimulation resulted in P=24 cm H 2 O±4 SE, 13 cm H 2 O±2 SE, 43 cm H 2 O±3 SE during stimulation at the T 9 /T 10 , T 13 /L 1 , and combined stimulation at both sites, respectively, Spinal root section resulted in a significant fall in P during SN. For example, during upper and lower SN, P fell to 30 cm H 2 O±3 SE (p<0.05). Therefore, SN (like SCS as demonstrated in prior studies) also involves spinal cord pathways. These results also indicate that SCS is superior to SN as a means of producing changes in P, which is, in turn, superior to SA.
By these results, it shown that: a) epidural spinal cord stimulation (SCS) is superior to surface stimulation of spinal nerves (SN) which, in turn, is superior to surface stimulation of the abdominal wall (SA), in terms of airway pressure generation, and b) as with epidural spinal cord stimulation, surface stimulation of the spinal nerves results in activation of spinal cord pathways.
An example of a suitable stimulation apparatus for applying the electrical stimulation pulses to the epidural electrodes as described above is set forth in detail in U.S. Pat. No. 5,678,535 issued to Anthony F. DiMarco, the disclosure of which is expressly incorporated by reference herein. Most preferably, a stimulator apparatus for carrying out the method of the present invention comprises a patient-implanted radio-frequency (RF) receiver and stimulation pulse generator connected to the stimulation electrodes. A battery-powered external stimulation controller includes an RF antenna for transcutaneously transmitting RF stimulation control signals and energy into the implanted RF receiver-stimulator so that the receiver-stimulator selectively passes electrical stimulation pulses to the implanted electrodes in accordance with the RF signal. Those of ordinary skill in the art will recognize that the present expiratory muscle stimulation method to produce cough may be combined with the method for electrical stimulation of the respiratory muscles to achieve artificial ventilation in a patient as described in the aforementioned U.S. Pat. No. 5,678,535.
The invention has been described with reference to preferred embodiments. Obviously, modifications and alterations will occur to others upon reading and understanding the preceding specification. 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.
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A method and apparatus are provided for electrical stimulation of the expiratory muscles in a human or other mammal to produce cough in patients with spinal cord injuries resulting in paralysis of their expiratory muscles. The method of electrically activating expiratory muscles of a human patient or other mammal includes positioning a first epidural electrode at a first location on the dorsal surface of a spinal cord of a patient and a second epidural electrode, if necessary, at a second location on the dorsal surface of the patient's spinal cord. The first epidural electrode is positioned on the spinal cord dorsal surface in the region of the T 9 -T 10 spinal root level, while the second epidural electrode is positioned in the region of the lower thoracic spinal root, at the T 12 -L 1 spinal cord level. Electrical stimulation pulses are selectively passed to the first and second epidural electrodes from an implanted radio-frequency receiver and stimulation pulse generator to activate expiratory muscles of the patient to produce cough. The invention provides a safe, effective, and portable means by which spinal cord injured patients are able to clear secretions more easily and thereby improve their lifestyle and reduce the morbidity and mortality due to respiratory complications.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates in general to elevator systems, and more specifically to arrangements for detecting the derailment of the counterweight in a traction elevator system, such as caused by an earthquake.
2. Description of the Prior Art
Damaging earthquakes are likely to occur in certain well defined earthquake zones of the world. The need for earthquake detection, or damage detection, in certain elevator systems installed in earthquake zones was recognized after the California earthquake in 1971.
U.S. Pat. No. 3,791,490 discloses an arrangement for detecting abnormal horizontal counterweight movement, with the arrangement including a vertically oriented wire strung tautly in the hoistway. A metallic ring mounted directly to the counterweight frame encircles the wire without contact therewith during normal operation. Horizontal movement of the counterweight such that the ring contacts the wire, grounds the wire through the counterweight frame, wire supporting ropes, drive sheave and bearings. When grounding of the wire is detected, the resulting signal is used to modify the operation of the elevator system. For example, the elevator car may be stopped with regard to floor level, and the car may then be operated at a reduced speed to the closest floor in a direction away from the counterweight.
With certain buildings and building heights it is possible for the wire to sway and/or vibrate to such an extent that it contacts the ring on the counterweight during normal operation of the elevator system. When this happens, the elevator car is stopped and taken out of service unnecessarily.
SUMMARY OF THE INVENTION
The present invention improves upon the ring and wire counterweight derailment detection arrangement of the prior art by eliminating false triggering due to wire sway or vibration. The improvement is accomplished with minimal hardware and installation cost, the improvement is provided without the necessity of running a trail cable to the counterweight, and the improvement is obtained without changing or modifying the detection control circuitry. Further, the improved arrangement may be added to existing elevator installations, as easily as being applied to a new elevator installation. Instead of connecting the metallic ring directly to the grounded counterweight frame, it is insulatingly mounted on the counterweight. A wire is connected from the electrically insulated metallic ring to ground through a switch, such as a microswitch, with the switch having an actuating arm biased against the nose guide surface of one of the counterweight guide rails. As long as the actuating arm is biased against the guide surface of the guide rail, the switch is held in an open position, and inadvertent contact between the ring and wire is not detectable. If the counterweight should move outside of its normal vertically guided path, such as due to an earthquake, to such an extent that the actuating arm is moved off of the guide rail guide surface, the switch immediately closes its contacts and the detection circuitry is enabled.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention may be better understood and further advantages and uses thereof more readily apparent when considered in view of the following detailed description of exemplary embodiments, taken with the accompanying drawings in which:
FIG. 1 is a perspective view of an elevator system which may be constructed according to the teachings of the invention;
FIG. 2 is a partially schematic diagram which illustrates the teachings of the invention;
FIG. 3 is a fragmentary, perspective view illustrating an exemplary mounting arrangement for the electrically insulated ring and microswitch shown in FIG. 2; and
FIG. 4 is a cross sectional view taken through the electrically insulated ring shown in FIG. 3, in the direction of arrows IV--IV.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to FIG. 1, there is shown a perspective view of an elevator system 10 of the traction type having an elevator car 12 and a counterweight 14 interconnected via a plurality of metallic, wire ropes 16 which are reeved over a metallic, grounded, traction sheave 18. Compensation ropes 20 interconnect the bottoms of the car and counterweight via a compensator sheave 22. Traction sheave 18 is driven by a traction drive machine 24, which may include an AC or DC drive motor. Drive machine 24 is controlled by elevator control 26, such as set forth in detail in U.S. Pat. Nos. 3,750,850 and 4,416,352. Elevator car 12 and counterweight 14 are mounted for guided, vertical movement in a building 30 via car and counterweight guide rails, such as car and counterweight guide rails 32 and 34, respectively, and guide roller assemblies mounted on the car and counterweight which coact with the guide rails. For example, guide roller assemblies 35 and 35' are shown mounted on elevator car 12 and coacting with guide rail 32, and guide roller assemblies 37 and 37' are shown mounted on counterweight 14 and coacting with guide rail 34. Guide rails similar to guide rails 32 and 34 would also be disposed on the opposite sides of the car and counterweight, but they are not shown in FIG. 1 in order to clarify the drawing.
A prior art counterweight derailment detector includes a vertically extending metallic wire 36 tautly strung the length of the hoistway 28, between first and second electrically insulated mounting termination points 38 and 40, respectively. In a preferred embodiment, wire 36 is disposed in the space between the elevator car 12 and counterweight 14. A metallic ring 42 is mounted on the counterweight 14, such that it is electrically grounded, e.g., by mounting it directly on the metallic counterweight frame 44 which is grounded through the wire ropes 36 and traction sheave 18, as indicated at 46. Control 48 applies an electrical potential to wire 36, it detects contact between wire 36 and ring 42, and it modifies the elevator control 26, as indicated by broken line 50, such as by stopping the elevator car 12 and then moving it to floor level in a travel direction away from the counterweight 14. Since suitable control 48 is shown in the hereinbefore mentioned U.S. Pat. No. 3,791,490, and since the present invention does not modify the control, it will not be described in detail.
Since building sway and/or wind currents in the hoistway may cause wire 36 to vibrate and sway, with the amount of vibration or sway being proportional to building height, it is possible for contact to occur between the wire 36 and ring 42 without abnormal horizontal movement of the counterweight. This results in an unnecessary stop of the elevator car 12, as well as the loss of the elevator car from service until authorized personnel reset the control.
The present invention overcomes the possibility of false triggering of the ring/wire counterweight derailment detector arrangement, with little added hardware and installation costs, and without running a traveling cable to the counterweight, without requiring continuous contact between a sliding contact brush and a wire for the length of counterweight travel, and without requiring the placement of a battery on the counterweight which is charged via an energized rail and contact shoe.
FIG. 2 schematically sets forth the teachings of the invention. A metallic ring 52, similar to the uninsulated ring 42 shown in FIG. 1, encircles wire 36, but instead of connecting ring 52 directly to the grounded counterweight frame 44, it is electrically insulated from frame 44, as indicated by electrical insulation 54. Wires 55 and 55' connect ring 52 to ground 46 via a switch 56 mounted on the counterweight 14, such as by a microswitch having an actuating arm 58 and a contact set 60. A spring 62 biases the contact set 60 towards the closed position of the switch 56. The contact set 60 is opened against the bias of spring 62 by disposing actuating arm 58 against the counterweight guide rail 34. Guide rail 34 has a substantially T-shaped cross-sectional configuration, having stem and back portions 62 and 64, respectively. Stem portion 62 has first and second flat, opposed side guide surfaces 66 and 68, respectively, and a flat guide surface 70 located at the stem nose which extends between the side guide surfaces 66 and 68. A roller 72 mounted at the extreme outer end of the actuating arm 58 is preferably disposed to contact and roll on the flat guide surface 70. Thus, any horizontal movement of the counterweight 14 and/or movement of guide rail 34, sufficient to move roller 72 off of the guide surface 70, will result in switch 56 being operated to its closed position, electrically grounding metallic ring 52. Thus, the control circuitry 48 will be armed or enabled to detect contact between wire 36 and ring 52. For example, a conductive solid state switch in control 48, such as a transistor, may be turned off by such contact, changing the state of a relay formerly energized by the conductive solid state switch. Thus, actual physical damage to the elevator system is required before the control 48 is armed or enabled, unlike the prior art arrangement.
FIG. 3 is a fragmentary, perspective view of suitable mounting arrangements for mounting the insulated metallic ring 52 and switch 56 on the counterweight 14. As illustrated in FIG. 4, which is a cross sectional view of ring 52 taken between and in the direction of arrows IV--IV in FIG. 3, electrical insulation 54 may be disposed to completely surround ring 52, and a mounting bracket 74 mounts the insulated ring to the counterweight frame 44. For example, bracket 74 may include a ring portion 76 which tightly encircles the insulated ring, an integral arm 78, and an L-shaped member 80 which connects arm 78 to a beam 82 of the counterweight frame 44.
Switch 56 may be suspended from the metallic mounting frame 84 of the counterweight guide roller assembly 37' via a metallic bracket arm 86. Wire 55 interconnects metallic ring 52 with a first electrical lead of switch 56, and wire 55' connects a second electrical lead of switch 56 to a grounded portion of the counterweight, such as to bracket arm 86. Arm 86 is connected to the metallic frame 84 of the guide roller assembly via bolts 88, and frame 84 is bolted to the counterweight frame 44 via bolts not shown in FIG. 3.
A counterweight derailment detector constructed according to the teachings of the invention may thus be installed on new or existing elevator installations quickly and easily by merely attaching two brackets 74 and 86 to the counterweight 14, with bracket 74 including the insulated metallic ring 52 and bracket 86 including switch 56. Wire 55, which may be pre-connected to ring 52, is connected to one side of switch 56. The other side of switch 56 may be pre-connected to bracket arm 86. Ring/wire type counterweight detectors of the prior art may be just as quickly replaced, without modification to the control 48.
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A traction elevator system having an elevator car and a counterweight. Counterweight derailment, such as due to an earthquake, is detected via a vertically oriented wire strung tautly in the hoistway, a metallic ring on the counterweight which encircles the wire, control connected to the wire for detecting contact between the ring and wire, and a switch on the counterweight which enables the control to detect contact between the ring and wire only after predetermined abnormal horizontal movement of the counterweight.
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This is a division, of application Ser. No. 562,011, filed Mar. 25, 1975 now U.S. Pat. No. 4,020,727.
BACKGROUND OF THE INVENTION
The invention pertains to improvements to machinery to wind capacitors, and particularly those capacitors which incorporate more than one capacitor in the same winding. Machines have heretofore been designed to wind capacitors of this type. In particular, one prior art machine has met considerable commercial success. That machine, the semi-automatic Hilton Capacitor Winding Machine, manufactured by Hilton Industries, Inc., Glen Falls, New York, provided a partial answer to the industry's need for a capacitor winding machine. Specifically, this machine incorporated means for supplying the necessary dielectric layers, foil, and terminals to an arbor which was winding the capacitor. The machine automatically fed the proper lengths of foil to form the various capacitor electrode and, at approximately the proper time, fed foils with metallic tabs which formed the terminals of the capacitor.
Unfortunately, this machine, despite some automatic operations, required the full-time attendance of an operator. Among the functions that this operator had to perform were threading the severed ends of the dielectric layers onto the arbor to allow the machine to wind another capacitor, sealing the ends of the wound capacitor to prevent it from unraveling, and removing the wound capacitor from the arbor. The operator also had to reorient the capacitor tabs so that they assumed the proper angular relationship, and, when the finished capacitors tended to collapse, manually insert a structural reinforcement at the beginning of the winding of the succeeding capacitors.
Beside the cost of the labor necessitated by this machine, manual operations are subject to human error. Therefore, it has been a long-standing goal in the capacitor winding industry to reduce the amount of manual labor needed to produce wound capacitors.
Prior attempts to design an automatic capacitor winding machine have not met with commercial success. These attempts have encountered numerous problems.
One major problem is automatically removing the wound capacitor from the winding arbor without telescoping of the capacitor, i.e. the inner windings of the capacitor body pulling out of and extending past the main body of the capacitor. This problem seems to be caused by the friction between the innermost winding and the arbor, which tends to keep the innermost winding on the arbor. Unfortunately, normal lubrication techniques (oil, grease) cannot be used to reduce the friction since they would degrade the capacitor. Attempts to strip the capacitor off the arbor by close tolerance strippers have previously failed because of the wear suffered by these parts, destroying the tolerances.
Another problem left unsolved by the prior art machines is automatically preventing the collapse of the capacitor when stripped off the arbor. In the semi-automatic machines, structural inserts were manually fed into the capacitor. However, in automating the machine, prior attempts have not been successful in designing an automatic structural insert device.
Another problem is to insert the tabs (terminals) of the capacitor in the proper angular relation. This requires that the machine know the exact angular position of the first tab, so that later tabs can be properly inserted. Prior art machines attempted to solve this problem by counting arbor rotations. However, this system has proved expensive and unreliable.
Moreover, most prior art attempts to design an automatic capacitor winding machine have involved designing a machine from scratch. This has resulted in expensive, complicated, and unreliable machines. The present invention can be used to modify prior art machines, and in fact, such a modification is the preferred embodiment of the present invention.
Consequently, it is an object of the present invention to attain an automatic capacitor winding machine, preferably in a form that permits modification of prior art semi-automatic machines.
It is also an object of the invention to obtain a mechanism to strip capacitors off arbors without capacitor telescoping and with minimum stripper wear.
It is also an object of this invention to obtain a machine that knows the position of a tab inserted into a capacitor without counting arbor rotations.
Another object of this invention is to obtain an automatic structural insert means, preferably constructed to fit within the confines of the prior art semi-automatic machines.
The present invention has met the above and other objects. Although the features of the present invention are embodied in a specific automatic capacitor winding machine, from the below description, one skilled in the art will be able to embody these features into other environments, not limited to capacitor winding machines.
SUMMARY OF THE INVENTION
The preferred embodiment of the present invention comprises a capacitor winding machine with a bifurcated arbor. Lateral transport means are provided for moving the bifurcated arbor axially from an advanced position to a retracted position. Additionally, rotational motor means are provided which rotate the bifurcated arbor about its axis to wind upon the arbor the various layers comprising a wound capacitor.
Appropriately located on the face of the capacitor winding machine are continuous rolls of the supplies necessary to form the capacitor. Thus, there are continuous rolls of the paper which form the capacitor dielectric layers. There are also continuous rolls of metallic foil which form the capacitor electrodes. Also, there are continuous metallic foil rolls with tabs periodically bonded thereto which are inserted to become the tabs (terminals) of the completed capacitor.
The preferred embodiment of the invention also has means to supply a structural insert for the capacitor. This structural insert is preferably located at the beginning of the second capacitor section, and functions to prevent the collapse of the capacitor after its removal from the bifurcated arbor. This automatic structural insert means, not found on the prior art machines, in the preferred embodiment is of a form that enables it to be incorporated in the limited remaining space on prior art machines.
Similarly, transport means are provided. These transport means carry the ends of the dielectric layers forming the capacitor in front of the bifurcated arbor when it is in its retracted position. Registering means are provided to index said bifurcated arbor with its slot in the direction parallel to the plane of the dielectric layers in front of the bifurcated arbor prior to the bifurcated arbor moving from its retracted position to its advanced position.
Stripper means are provided to remove the wound capacitor from the bifurcated arbor. These means are particularly adapted to prevent the capacitor during the stripping process from telescoping, i.e., to prevent the inner wound layers of the capacitor from extending beyond the body of the capacitor.
The present invention also inserts the capacitor tabs (terminals) into the capacitor as it is being wound so that in the completed capacitor the tabs have a predetermined angular relationship with respect to each other. These means include photoelectric means which accurately senses the angular location of the first tab previously inserted into the capacitor.
Generally speaking, the objectives of the present invention are attained by the provision of a photoelectric device for sensing when an object which travels a predefined path and which crosses a line a plurality of times is at a first point of crossing on the path which is nearest a first end of the line comprising, a light detector having a relatively narrow angle of light acceptance located proximate the first end of the line and responsive to light impinging thereon, and a light source proximate the second end of the line for transmitting a beam of light, which is wider at a point of crossing on the path which is further from the first end of the line than the first point of crossing than the widest portion of the object, along the line, whereby the object prevents the beam from impinging on the detector only when the object is at the first point of crossing on the path closest to the first end of the line.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plan view of a capacitor wound on the machine of the present invention.
FIGS. 2A and B are front views of a schematic representation of the machine of the present invention.
FIG. 3 is a side view taken along line 3--3 of FIG. 2A of the machine of the present invention showing in detail the structural insert means.
FIG. 4 is a plan sectional view along line 4--4 in FIG. 3 of the structural insert guide means.
FIG. 4A is a side sectional view along line 4A--4A of FIG. 3 of the structural insert means.
FIG. 5 is a plan view taken along line 5--5 of FIG. 3 showing the knife assembly for serving the structural insert.
FIG. 6 is a front view of the arbor and elevator apparatus.
FIG. 7 is a side sectional view taken along line 7--7 of FIG. 6 of the bifurcated arbor and lateral transport means in the machine of the present invention.
FIG. 8 is a rear view of the machine of the present invention showing the rotational motor means and registering means for the bifurcated arbor.
FIGS. 9-14 are schematic representations of the machine of the present invention during different stages of its operation.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 illustrates a capacitor wound on the machine of the preferred embodiment of the present invention. Capacitor 1 is a dielectric-conductive layer sandwich rolled into a right cylindrical shape. In the preferred embodiment, capacitor 1 comprises outer dielectric layers 3 and 5 and inner dielectric layers 7 and 9. Dielectric layers 3-9 may be made from paper approximately 0.0003 inch thick. Disposed between inner dielectric layer 9 and outer dielectric layer 5 is common electrode 11. Disposed between inner dielectric layer 7 and outer dielectric layer 3 are capacitor electrodes 13 and 15. In the preferred embodiment, common electrode 11 and capacitor electrodes 13 and 15 are constructed of aluminum foil about 0.0002 inch thick.
Capacitor electrode 13 is located near the center of the capacitor 1; whereas capacitor electrode 15 is placed after electrode 13 and spaced some distance therefrom. In contact with common electrode 11 and capacitor electrode 13 and 15 are tab webs 17, 19 and 21, respectively. Bonded to and extending axially from tab webs 17, 19 and 21 are tabs 23, 25 and 27, respectively. For reasons that will become evident below, tabs 23, 25 and 27 are located near the end of their respective tab webs farthest from the center of the capacitor. These tabs are bonded to the contacts that extend through the top of the metal capacitor can.
Capacitor 1 actually contains two capacitors: a relatively small capacitor is formed by capacitor electrode 13 and common electrode 11, hereinafter referred to as first capacitor section 12; and a relatively large capacitor is formed by capacitor electrode 15 and common electrode 11, hereinafter referred to as second capacitor section 14. One will also note that there are two dielectric layers between the common electrode and capacitor electrodes.
Capacitor 1 also has a structural insert 29. Insert 29 is approximately .003 inch thick. Structural insert 29 is preferably located in second capacitor section 14, i.e., the larger capacitor. This insures that the reduction in capacitance caused by the additional separation of the respective capacitor electrodes is negligible compared with the total capacitance of the capacitor.
In addition, structural insert 29 is preferably placed as near as possible to the interior of capacitor 1. Structural insert 29 provides structural support for capacitor 1 and helps prevent the collapse of capacitor 1 after it is stripped from the arbor upon which it is wound.
Capacitor 1 is the capacitor wound on the preferred embodiment of the present invention. From the specification below a person skilled in the art wil recognize that the present invention is adaptable to automatically wind capacitors made from other materials and even adaptable for machines that serve other purposes. For example, plastic layers could be used for the dielectric layers in capacitor 1; or vacuum deposited metal on a plastic carrier could be substituted for both a dielectric layer and electrode.
FIG. 2 is an illustration of the capacitor winding machine of the present invention. FIG. 2 is in two parts -- FIGS. 2A and 2B. The preferred embodiment of the present invention is a modified prior art capacitor winding machine. For the most part, the modifications comprising the present invention appear in FIG. 2B, as will be more fully understood from the description below. Except as noted below, FIG. 2A is a schematic representation of the prior art semi-automatic Hilton Capacitor Winding Machine.
In keeping with the schematic nature of FIG. 2, many details have been omitted, in part or in whole. For example, generally tension arms for the layers have been omitted from the figure. The friction brakes associated with dielectric layer supply hubs are another example of the omission of items readily supplied by one skilled in the art.
The central timing means to which reference will often be made below is also not shown. It causes each of the elements of capacitor winding machine 1 to operate at the proper time in conformity with the description of the operation of the machine. In the preferred embodiment, the timing means comprises both timing relays, electronic timing means, and other well-known timing techniques. These items, and similar items not shown or described, and their application to this invention, are well known to those skilled in the art.
In FIG. 2A, the apparatus supplying the dielectric layers, electrodes, and tab webs for capacitor 1 is schematically diagrammed. Each component of capacitor 1 is supplied from a continuous roll of that component. That is, outer dielectric layer 3 is provided from dielectric (paper in the preferred embodiment) layer roll 31. Similarly, dielectric layers 5, 7 and 9 are provided from continuous dielectric layer rolls 33, 35 and 37. Common electrode 11 is supplied from continuous foil roll 39; capacitor electrode 13 and 15 are supplied from continuous foil rolls 41. Tab web 17 is supplied from continuous web roll 43 with tabs 23 (not shown) periodically bonded thereto. Similarly, continuous web roll 45 provides tab webs 19 and 21. Structural insert 29 is supplied from paper roll 47.
The path of the various dielectric layers, webs and electrodes is clearly shown in FIG. 2A. By way of example, outer dielectric layer 5 comes off dielectric layer roll 33. Dielectric layer roll 33 is mounted upon a rotatable hub 49. Dielectric layer 5 is threaded upwards around idler roller 51. Idler roller 51 is mounted upon arm 53 which in turn is pivoted on shaft 55 to provide constant tension in dielectric layer 5 in accordance with teaching well-known to one skilled in the art.
From idler roller 51, dielectric layer 5 is threaded downwards around idler roller 57 and between guide rollers 59. Guide rollers 59 do not touch, or even compress the layers passing therebetween. The path taken by dielectric layer 3 is the mirror image of that taken by dielectric layer 5.
The path taken by dielectric layers 7 and 9 are also mirror images of one another. Dielectric layer 9 is supplied by dielectric layer roll 37 which is mounted upon hub 61. From dielectric layer roll 37, dielectric layer 9 is threaded around idler rollers 62, 63, 65, alongside knife assembly 501 and between guide rollers 59.
The path of common electrode 11 and capacitor electrodes 13 and 15 are also clearly shown in FIG. 2A. For example, common electrode 11 is supplied from continuous foil roll 39. Foil roll 39 is mounted upon hub 67. From continuous foil roll 39, common electrode 11 is threaded up around idler roller 69, against idler roller 71, through drive assembly 73 and between guide rollers 59.
A hub brake means 66 is provided for hub 67. It includes idler roller 69 which is mounted on one end of arm 68. The other end of arm 68 is rotatably mounted on shaft 70. Also pinned to arm 68 is piston rod 72 of air cylinder 74 and one end of cable 76. The other end of cable 76 is grounded at 78. Normally the center portion of cable 76 passes around the periphery of brake drum 80 of hub 67 without engaging its surface. However, when air cylinder 74 is operated to withdraw piston rod 72, arm 68 rotates about shaft 70 and draws cable 76 against the surface of brake drum 80, imparting a frictional drag sufficient to stop the rotation of hub 67.
Drive assembly 73 consists in a pertinent part of a drive roller 75 and idler roller 77. Common electrode 11 is fed between drive roller 75 and idler roller 77. Idler roller 77 is biased by means not shown against drive roller 75 and drive roller 75 is driven, at the appropriate times, as described below. Drive roller 75 also has a slip clutch that permits the electrode to be pulled through the engaged drive roller 75 and idler roller 77 faster than drive roller 75 is being driven.
There are means, also not shown, for moving both drive roller 75 and idler roller 77 out of contact with capacitor electrode 15 and common electrode 11. As will become clearer after the description below, these means are provided to remove unnecessary drag on capactor electrode 15 and common electrode 11 when these electrodes are drawn from supply rolls 39 and 41 by arbor 117 at high speed.
Immediately following drive assembly 73 is a rotary cutter 79. Rotary cutter 79 comprises a blade 81 mounted upon shaft 83. Rotary cutter 79 is driven by means (not shown) at the appropriate time. Because of its location above and adjacent to the path of common electrode 11, when driven, blade 81 of rotary cutter 79 will pass through and sever common electrode 11.
Drive assembly 73 also includes guide plate 85. After common electrode 11 has been severed by rotary cutter 79 and upon the activation of drive roller 75 forcing common electrode 11 to move downward, guide plate 85 and the outside surface of knife assembly 501 direct common electrode 11 downward and into guide rollers 59.
The tab webs are supplied in a like manner. For example, tab web 17 is continuously supplied from tab roll 43. Tab roll 43 is rotatably mounted upon hub 87. From tab roll 43 tab webs 17 are threaded into drive assembly 89.
Drive assembly 89 includes a drive roller 91 and an idler roller 93. Idler roller 93 is biased against drive roller 91 by means not shown; drive roller 91 is driven by means schematically shown by gear 95. As more fully explained below, tab web 17 is periodically driven by drive assembly 89, under control of the central timing control.
Between idler roller 93 and drive roller 91, tab web 17 is threaded across ledge 97. Mounted above ledge 97 is reciprocating cutter 99. Reciprocating cutter 99 includes a blade 101 mounted upon a rotating shaft 103. When driven, by means not shown, shaft 103 rotates causes the cutting edge of blade 101 to sever tab web 17.
Disposed some distance in front of drive assembly 89 is a photodetector assembly (shown only on drive assembly 89 for tab webs 19 and 21 which are supplied from the same supply roll). The photodetector assembly includes a light source 107 and a light sensitive element 109. Photodetector assembly is positioned so that only tabs 23, 25 and 27 pass therebetween and the solid foil portions of tab webs 17, 19 and 21 do not pass therebetween. After passing from drive assembly 89, tab web 17 is directed between guide rollers 59.
Drive assemblies 89 associated with tab web 17 and 21, respectively are not equidistant from the centerline of the capacitor winding machine. Drive assembly 89 associated with tab web 17 is closer to the centerline than is drive assembly 89 associated with tab web 21. The difference is distance to the centerline is equal to the distance between tabs 23 and 27 in wound capacitor 1. Thus, when reciprocating cutters 99 cut both tab webs 17 and 21 simultaneously, tab 23 will be inserted the proper distance in front of tab 27 into capacitor 1. One skilled in the art will recognize that the same result could be attained by having drive assemblies 89 equidistant from the centerline but operating reciprocating cutters 99 sequentially, the time between the operation of the two cutters 99 selected so as to insure that tab 23 is inserted the proper distance in front of tab 27.
The description of the apparatus as shown in FIG. 2A to this point has primarily involved the apparatus of the prior art. There has not been included any of the principal modifications that form the present invention. A principal improvement provided by the present invention is automatically inserted structural insert 29 and its associated apparatus.
The following description of the structural insert means can be best understood by referring to FIGS. 2A, 3, 4 and 4A. From structural insert roll 47, structural insert 29 is threaded into the drive assembly 301. Drive assembly 301 includes a drive roller 303 and idler roller 305. Drive roller 303 is mounted upon shaft 307 which is attached to the shaft of motor 309 by drive chain 311. Motor 309 is activated in accordance with the description below by the central timing means. Idler roller 305 is biased against drive roller 303 by means also not shown.
Structural insert 29 is driven into guide 313 as illustrated both in FIG. 3 and FIG. 4. Guide 313 includes two face plates 315 and 317. Face plate 315 has an L-shaped extension 319 which serves as a mounting bracket for guide 313. Separators 321 and 323 are disposed between face plates 315 and 317 to hold them in a parallel relationship and to form a channel 325. Structural insert 29 passes through channel 325.
Upon exiting from channel 325, structural insert 29 is guided downward by tongue 327 of back plate 317 into knife means 501 (FIG. 4A). Structural insert 29 passes through a channel 503 in knife body 505, which body has a cutting edge 506. Slidably mounted on knife body 505 is shearing blade 507 having a cutting edge 508. Shearing blade 507 has a rectangular notch 509 on one face through which structural insert 29 normally moves. Shearing blade 507 also has two slots 511 and 513 through which bolts 515 pass. Bolts 515 are fixed in knife body 505. Bolts 515 carry springs 517 which bear against the underface of the head of bolts 515 and the top surface of shearing blade 507, biasing the bearing surface of shearing blade 507 against the bearing surface or top of knife blade 505.
Particularly important to the design of knife means 501 is the shape of slots 511 and 513. Slot 511 is straight and oriented at an angle to the long surface 510 of rectangular notch 509. Slot 513 is arcuate and oriented substantially parallel to slot 511.
Shearing blade 507 is moved by the combined action of air cylinder 519 and spring 521. As a person familiar with pneumatics will clearly recognize, when the piston of air cylinder 519 is forced outwards by air introduced into the cylinder under control of the central timing means, shearing blade 507 will be forced to the right (as viewed in FIG. 5) compressing spring 521. Contrariwise, when the pressure in air cylinder 519 returns to the ambient, then compressed spring 521 will force shearing blade 507 back to its rest position, the position shown in FIG. 5.
Tongue 327 extends downward in a curved fashion toward shearing blade 507. In the preferred embodiment, the tip of tongue 327 does not contact shearing blade 507 when shearing blade 507 is in its unoperated position. However, shortly after shearing blade 507 begins its forward movement, surface 510 contacts the tip of tongue 327 springing it outward. When shearing blade 507 returns to its unoperated position, tongue 327 springs back to its rest position.
Because of the angular relationship of slots 511 with that of the long surface 510 of notch 509 and sides of channel 503, shearing blade 507 will completely cover channel 503 when it has moved to its extreme operated position. However, because of the arcuate nature of slot 513 in contrast to the straight slot 511, surface 510 of rectangular notch 509 does not proceed to cover channel 503 in a uniformly parallel manner. Rather, the right-hand end of channel 503, as viewed in FIG. 5, is covered first. As shearing blade 507 proceeds to its fully operated position, it progressively covers more and more of channel 503 until it finally covers the left-hand end. Thus, structural insert 29 is sheared by knife assembly 501 in much the same nature as an ordinary scissor shears a sheet of paper. Because of this design, much less force is needed to cut structural insert 29 than if shearing blade 507 traveled in a parallel fashion across slot 511. Moreover, because of the relatively narrow design of knife means 501, the entire assembly can be accommodated on an unmodified prior art machine.
From knife assembly 501, structural insert 29 continues downward into guide rollers 59. A guide plate 329 (FIG. 3) provides a surface which aids the leading edge of insert 29 between guide rollers 59.
It should be noted that structural insert 29, despite its relative lack of body (paper apprxomately 0.003 inch thick), is driven from above by drive assembly 301, guide 313 and knife means 501, and between guide rollers 59. "Pushing" structural insert 29 through guide 313 and knife means 501, rather than pulling it through knife means 501, permits placing drive assembly 301 near structural insert roll 47 and provides space for knife assembly 501 without major reconstruction of the dielectric layer and electrode paths of the prior art machine.
The length of structural insert 29 wound into capacitor 1 is determined empirically. Structural insert 29 serves to provide support for capacitor 1 to prevent its collapse. However, it should not be overly long or it will unduly affect the capacitance.
FIG. 2B illustrates the lower portion of the capacitor winding machine of the present invention. Repeated in FIG. 2B are guide rollers 59 and idler rollers 57 of FIG. 2A. Also shown are dielectric layers 3, 5, 7 and 9. All four dielectric layers enter guide rollers 59. From guide rollers 59, the dielectric layers are threaded downwards around idler rollers 114 and 115 and around bifurcated arbor 117. Arbor 117 includes two tangs 119 and 121 with a slot 123 (FIG. 6).
Idler roller 115 is offset slightly more to the right than idler roller 114, as viewed in FIG. 2B. These two rollers cause the various layers to be wound to be brought closer together and "smoothed" out. This latter function is most important to insure that the layers are not wrinkled in wound capacitor 1.
In accordance with this invention arbor 117 both rotates around its axis and translates axially, i.e. moves laterally along its axis. For this purpose, rotational motor means and lateral transport means are provided.
Arbor 117 is mounted on shaft 125. Shaft 125 is pressed into the inner race of bearings 127 and 129. The outer race of bearings 127 and 129 bear on the interior surface of hollow piston rod 131 of air cylinder 133.
Shaft 125 can both translate axially and rotate. A commercially available unit, marketed by Alkon Products, Wayne, New Jersey, is called an air extensible drill unit. This unit is shown schematically in FIG. 7.
As shown in FIG. 7, shaft 125 is hollow and has splines 135 on its inner diameter. Meshing with spines 135 are complementary splines 137 carried on a shaft 139. Shaft 139 is affixed to pulley 141. Pulley 141 carries timing belt 143. Under the movement of timing belt 143, arbor 117 will rotate upon its axis. Further, under the control of the central timing means, arbor 117 moves axially in accordance with the movement of piston rod 131 in air cylinder 133.
As previously described, a principal object of the present invention is to automatically produce capacitors whose inner windings have not telescoped beyond the capacitor body. Consistent with this object the present invention strips wound capacitor 1 off arbor 117 without causing the inner windings of capacitor 1 to extend beyond the body of capacitor 1. A review of the difficulties in accomplishing this object will lead to a fuller understanding of the present invention.
Some prior art machines also attempted to strip wound capacitors off an arbor by "pushing" the capacitor off the arbor. Although these machines sometimes worked initially, they eventually began to telescope the stripped capacitor. Their problem arose from the high wear of their parts. For example, in the method of the present invention, i.e., retracting the arbor axially through an opening in a plate, which blocks the capacitor and strips it off the arbor, the opening in the plate has to be only slightly larger than the diameter of the arbor. Otherwise, the inner windings of the capacitor could be drawn between the arbor and the plate, ie. "telescope" the capacitor.
However, in prior art machines, the opening in the stripper plate would not maintain its dimensions. It is subject to wear from at least these sources. First, the arbor rotates at high speed within the opening causing rotational frictional forces to wear and enlarge the opening. Second, the arbor's high acceleration and deceleration flexes the arbor and causes it to bear against the sides of the opening and further enlarge it. A third cause of wear is the arbor's axially translation through the opening. However, the arbor translates axially at relatively low speed.
It has been found that the wear due to the arbor's low speed axially translation is not significant. It is the wear from the arbor's flexing that appears most serious, closely followed by the wear caused by the arbor's high rotational speeds.
The present invention greatly reduces the wear to which the stripper means from the arbor's flexing and rotation. Thus, it consistently produces good capacitors over relatively long periods.
The stripper means includes a stripper plate 145 held in a spaced relationship from machine support plate 30 by spacers 147. At the center of stripper plate 145 is a circular opening 149 whose inner diameter is only slightly larger than the outer diameter of arbor 117. Coaxial with the center of opening 149 is a cunterbore 151 in the rear surface of stripper plate 145. Inserted in counterbore 151 is a ball bearing 153. The inner race of bearing 153 carries a sleeve bearing 155. The inner diameter of sleeve bearing 155 slidably supports arbor 117.
Mounted on the front of stripper plate 145 are hooks 157. Hooks 157 are arranged in a circle concentric with the center of opening 149. Riding on arbor 117 is stripper washer 159, preferably made of bronze.
As shown in FIGS. 6 and 7, arbor 117 passes through the center hole 161 of stripper washer 159. The stripper washer is restrained from moving axially along arbor 117 by stripper plate 145 and hooks 157. Moreover, since hole 161 is slightly larger than the outside diameter of arbor 117, stripper washer 159 is free to rotate on arbor 117. However, because of the limited friction between stripper washer 159 and arbor 117, after arbor 117 has rotated at a steady speed for a short period, stripper washer 159 will be rotating at approximately the same speed.
Both stripper plate 145 and stripper washer 159 are preferably made of bronze; arbor 117 is preferably made of stainless steel. Thus, the sliding action of arbor 117 on stripper plate 145 and stripper washer 159 will not score arbor 117. Although this sliding action may cause both stripper washer 159 and stripper plate 145 to wear, enlarging the clearance between arbor 117 and openings 149 and hole 161, as described above, because of the low lateral speeds of arbor 117, this wear is not excessive.
However, stripper washer 159 has substantially no wear due to arbor 117's flexing and rotation. Although arbor 117's rotational speed is high, stripper washer 159 rotates with arbor 117 so that there is little or no relative rotational motion between the two. Also, stripper washer 159 flexes with arbor 117, preventing wear to stripper washer 159 from this source. Thus, the clearance between stripper washer 159 and arbor 117 remains constant.
When arbor 117 translates laterally to its retracted position, the rear face of capacitor 1 bears against stripper washer 159. Because of the constant nominal clearance between arbor 117 and hole 161, there is no room for the inner windings of capacitor 1 to travel between the stripper washer 159 and arbor 117 and "telescope" out of the main body of capacitor 1. And, as just noted, this nominal clearance is not subject to a large variation because of wear. Of course, if for some reason undesirable wear does occur to stripper washer 159, it is easily and inexpensively removed and replaced.
FIG. 8 shows the motor for driving the arbor 117 and the registering means for registering arbo 117 so that slot 123 is in an absolutely vertical orientation. This orientation is necessary for proper "threading" of the arbor. Timing belt 143 engages pulleys 141 and 801. Pulley 801 is affixed to shaft 803 of motor 805. Pulley 801 also carries two cylindrical detents 807. Detents 807 are located on the same diameter of pulley 801 on either side of shaft 803. In the preferred embodiment, pulley 801 and pulley 141 have the same diameter. Thus, there is a one-to-one correspondence in the rotation of shaft 803 and arbor 117.
A pawl 809 is rotatably mounted on pin 811. When pawl 809 is rotated into a vertical orientation, shoulder 813 on pawl 809 will engage one of the two cylindrical detents 807 as they are carried by pulley 801 and prevent further rotation of pulley 801. The relationship of the detents is such that when pawl 809 engages either of the two detents 807, arbor 117 is stopped with slot 123 in a vertical orientation.
Pawl 809 is rotated by piston rod 815 of air cylinder 817. Air cylinder 817 is under the control of the central timing means.
In the preferred embodiment, in order to prevent unnecessary shock to the apparatus, before pawl 809 is rotated into position to engage detent 807 motor 805 is momentarily deenergized, which stops the rotation of pulley 801. Pawl 809 is then rotated into engagement position and motor 805 is re-energized to drive one of the detents 807 into engagement with pawl 809. Because the most that motor 805 can rotate before it is stopped by pawl 809 engaging detent 807 is 180°, motor 805 does not reach a high speed. Thus, detent 807 contacts shoulder 813 of pawl 809 positively, but without excessive force.
Motor 805, under proper control of the central timing means, provides two speeds: a jog (low) speed and a high speed. The jog speed is used until capacitor 1 has sufficient integrity in its inner windings to prevent the higher tension in the outer windings generated by the high winding speed to prevent capacitor 1's collapse when it is removed from arbor 117. In the preferred embodiment, the job speed is maintained until after structural insert 29 is in place.
Jog speed is also used near the completion of capacitor 1. Shortly prior to the severing of capacitor electrode 15 and common electrode 11, motor 805 returns to jog speed. Time is provided for motor 805 to stabilize at this low speed. Then, as described below, motor 805 is momentarily deenergized, stopping its rotation and halting the winding of capacitor 1. This stoppage allows drive rollers 75 and idler rollers 77 to move into contact with stationary electrodes 11 and 15. This procedure avoids moving non-rotating drive rollers 75 and idler rollers 77 into contact with the moving electrodes 11 and 15, and thus avoids the consequent damage that might occur to electrodes 11 and 15.
In FIGS. 2B and 6, the paper transport means can be seen. An elevator apparatus 601 is illustrated. Air cylinders 603 and 605 move piston rods 607 and 609 under control of the central timing means. Attached to piston rods 607 and 609 are support plates 611 and 613. Carried by support plates 611 and 613 are the following: transport means 615, capacitor sealing means 617, dielectric layer severing means 619 and conveyor control bar 621. Each of these means is now described in greater detail.
Paper transport means 615 includes two air cylinders 623 and 625. Air cylinder 623 is larger than air cylinder 625. These cylinders have piston rods 627 and 629 respectively, each of which carries a clamp 631. Clamps 631 comprise a rectangular portion 633, a rectangular rubber cushion 635 and a stainless steel face 637.
As one skilled in the art will recognize, when pistons 623 and 625 extend, faces 637 will automatically align because of the compressibility of rubber cushions 635 (rubber cushion 635 in the preferred embodiment has a hardness of around 60 durometer). Further, since air is supplied at the same pressure to both cylinders, piston rod 627 of larger air cylinder 625 will extend fully presenting a predetermined position for clamping dielectric layers 3-9. Moreover, one skilled in the art will recognize that the stainless steel faces 637 which contact paper layers 3 and 5 will not be corroded by the resins and other chemicals which might be present dielectric layers.
Capacitor sealing means 617 includes a water ejector 639. The water is supplied to water ejector 639 through conduit and fittings 641 which lead from pump 643. Pump 643 is also connected to water supply 647 by tube 645. Whenever elevator apparatus 601 descends (as described below), surface 642 of elevator apparatus 601 depresses piston 644 of pump 643 to pump a few drops of water from water supply 647 to water ejector 639.
Located directly below water ejector 639 is wetting roller 649. Wetting roller 649 includes a Delrin axle 651 mounted in a brass yoke 653. Rotating freely on axle 651 is a stainless steel cylinder 655 which is covered by a water retaining cork cylinder 657. These materials are selected both according to their function and their resistance to corrosion. One skilled in the art could substitute other materials having similar functions. For example, if water did not properly seal the capacitor, an adhesive or heat seal method could be substituted.
Yoke 653 is carried by piston rod 659 of air cylinder 661. Air cylinder 661 is mounted upon support plate 611 as shown in FIG. 6. In operation, when activated by the central timing means, piston rod 659 extends wetting roller 649 to contact the outer surface of rotating capacitor 1, thereby wetting and sealing it.
Dielectric layer severing means 619 includes an air cylinder 663 with an associated piston rod 665. Attached to piston rod 665 is a serrated blade 667. At the appropriate time under control of the central timing mechanism, piston rod 665 extends causing blade 667 to contact the then taut dielectric layers 3, 5, 7 and 9 and thereby sever them.
Also shown in FIGS. 2B and 6 is the capacitor conveyor means 669. This means includes a conveyor belt 671 which catches the wound capacitor after it is stripped off arbor 117. Motor 679 powers belt 671. Belt 671 conveys the capacitor to ramp 673. Gate 675, normally in the raised position, blocks ramp 673 and causes the leading end of capacitor to strike the side of ramp 673 with the cylinder's axis perpendicular to the length of ramp 673.
Air cylinder 677 lowers gate 675, under control of the central timing means, at the same time that dielectric layer severing means 619 is operated, thereby allowing wound capacitor 1 to roll down ramp 673. Thus, gate 675 prevents capacitor 1 from starting to slide down ramp 673 until the entire capacitor 1 is present in front of ramp 673. If not for gate 675, capacitor 1 might slide down ramp 673 askew.
The axle under arbor 117 upon which belt 671 rotates is attached to conveyor control bar 621. Ramp 673 also (as seen in FIG. 2B) is rotatably pinned on axle 672. Thus, belt 671 and ramp 673 follow the motion of elevator mechanism 601. That is, when the elevator mechanism descends, as described below, belt 671 also descends.
Also clearly shown in FIG. 2B is the tab sensing mechanism 201, which is a key part of the tab insert means. As has already been described, capacitor 1 has three tabs which must be accurately oriented with respect to each other. However, as long as the tab webs with which the tabs are associated contact the proper capacitor electrode, the relative position of the webs with respect to the capacitor is unimportant. Therefore, as will be more fully understood after reading the "Operation" below, the first tab 25 is inserted arbitrarily during the time when its tab web 19 will be in position to contact capacitor electrode 13. Upon insertion of tab 25, the central timing mechanism counts an appropriate number of turns of arbor 117. When the appropriate number of turns have occurred, it is the approximate time for the insertion of the remaining two tabs 23 and 27.
To insure that they are inserted at the precisely correct position, the exact rotational position of already inserted tab 25 must be known. This is accomplished through means of phototransistor 203 and light source 205. Light source 205 emits a relatively wide beam of light whereas phototransistor 203 is sensitive to a relatively narrow beam of light. During its rotation, tab 25 will cross light beam 205 twice: once when tab 25 is closest to light source 205, and once when tab 25 is closest to phototransistor 203. However, because of the wide beam emitted by light source 205, when tab 25 is closest to light source 205, tab 25 is not large enough to completely block the light from reaching phototransistor 203. But when tab 25 is closest to phototransistor 203, because of the narrow acceptance angle of phototransistor 203, it will block all light reaching phototransistor 203.
Thus, although tab 25 crosses the light beam twice, the light to phototransistor 203 is blocked only at one unique position of tab 25 during its rotational travels. This position is sensed by the central timing means and, as described below, causes tabs 23 and 27 to be inserted. Moreover, because both phototransistor 203 and light source 205 lie in a plane parallel to machine back 30, they are located as close as possible to machine back 30, which reduces the likelihood that an operator will accidentally strike and damage them.
OPERATION OF THE PREFERRED EMBODIMENT
FIGS. 9-14 show a capacitor being wound in various stages on the machine of the present invention. FIG. 9 shows the stage after a previously wound capacitor has been removed from arbor 117 and the machine is about to wind the subsequent capacitor. Dielectric layers 3, 5, 7 and 9 are shown led through guide roller 59, past idler rollers 114 and 115 and between closed clamps 631.
Common electrode 11 and capacitor electrode 13 have been fed so that their leading edges are near the convergence of dielectric layers 5 and 9 and layers 3 and 7, respectively. In the position when the converging dielectric layers are in motion, they exert a frictional pull on the electrodes. This frictional pull would cause the electrodes to advance if they were not restrained. The restraint is provided by hub brake means 66. That is, arm 68 has been rotated clockwise to draw cable 76 against brake drum 80 of hub 67, preventing the rotation of hub 67 and the advancement of electrode 11 (and 13).
Similarly, the leading edge of structural insert 29 is located between converging dielectric layers 7 and 9. Locked drive roller 303 restrains the movement of structural insert 29.
Clamps 631 are lowered by elevator apparatus 601. That is, piston rods 607 and 609 recede into air cylinders 603 and 605 respectively, carrying clamps 631 and their associated apparatus downward. This is illustrated in FIG. 10, where clamps 631 have carried the ends of dielectric layers 3, 5, 7 and 9 below arbor 117 which, until this point, has been retracted into the face of stripper plate 145. Arbor 117 has also been locked with its slot 123 in a vertical orientation by pawl 809 engaging one of detents 807.
When elevator assembly 601 has lowered clamps 631 to the furthest downward position, arbor 117 moves axially from behind stripper plate 145 through the action of air cylinder 133. Tangs 119 and 121 envelope dielectric layers 3, 5, 7 and 9 (see FIG. 10).
When arbor 117 is fully extended, the pressure in air cylinders 623 and 625 is reduced, thereby relieving to a predetermined extend the pressure between clamps 631. This predetermined lesser pressure is empirically determined to be sufficient to hold dielectric layers 3-9 between clamps 631 but permit withdrawal of dielectric layers 3-9 from between clamps 631 without damage to the dielectric layers.
Next, pawl 809 disengages detent 807 through means of air cylinder 817 and piston rod 815, and motor 805 is energized. Arbor 117 is driven through timing belt 143, pulley 141, shaft 139 and 125.
Motor 805 first rotates at a slow or jog speed. Referring to FIG. 11, as dielectric layers 3-9 begin to wrap around arbor 117, they will both be drawn from between clamps 631 and from supply rolls 31, 33, 35 and 37.
When the arbor has made a predetermined number of revolutions, and thus has a predetermined number of wraps of dielectric layers 3-9 around it, piston rod 72 is extended from air cylinder 72 to relieve the pressure cable 76 exerts on brake drum 80. Simultaneously, drive rollers 75 drive electrodes 11 and 13. Eventually, the leading edges of electrodes 11 and 13 will wrap around arbor 117. Since the rate at which rotating arbor 117 pulls electrodes 11 and 13 is greater than the rate at which drive rollers 75 drive electrodes 11 and 13, and since the slip clutches in drive rollers 75 allow electrodes 11 and 13 to be pulled faster through drive roller 75 and idler rollers 77 than the driven rotational speed of drive rollers 75, the feed speed of electrodes 11 and 13 is then governed by the rotation of arbor 117.
During this period, elevator apparatus 601 has caused transport means 615, dielectric layer severing mechanism 619, and capacitor sealing means 617 to be raised to their upper position. The capacitor winding machine at this stage is shown in FIG. 12.
Approximately at the same time that electrodes 11 and 13 are fed, tab web 19 is extended. Drive assembly 89 is energized, causing drive roller 91 to drive tab web 19 toward converging dielectric layer 3 and capacitor electrode 13. Tab web 19 is driven until photodetector assembly 105 senses the presence of tab 25. At this point, drive roller 91 is locked. However, the leading edge of tab web 19 has been fed to the point where the dielectric layer 3 and capacitor electrode 13 converge. However, since tab web 19 has not yet been severed from its supply roll 45, it is prevented from being drawn down past guide rollers 59 and wound into capacitor 1. FIG. 11 illustrates the capacitor winding machine 1 at this stage.
When the appropriate time arrives for tab web 19 to be inserted, reciprocating cutter 99 is energized, severing tab web 19 from supply roll 45 and allowing it to be drawn into capacitor 1. As previously mentioned, the exact location of web 25 is not critical. The only necessary criteria is that it overlie capacitor electrode 13.
When a predetermined length of capacitor electrode 13 has been wound upon arbor 117, determined by the number of arbor rotations, rotary cutter 79 severs capacitor electrode 13. Drive assembly 73 associated with electrode supply roll 41 continues to drive that electrode toward the converging dielectric layers 3 and 7 to form capacitor electrode 15.
Since arbor 117 has been pulling electrode 13 at a rate greater than drive assembly 73 can feed electrode 15, there will be a space between the end of electrode 13 and the beginning of electrode 15. That is, arbor 117 does not begin to pull electrode 15 until the leading edge is about to be wound into capacitor 1. Therefore, until this point electrode 15 moves slower than electrode 13, causing a space between the two electrodes.
At the same time the beginning of electrode 15 starts to wind into capacitor 1, structural insert 29 is inserted. Since the previous cycle the leading edge of structural insert has been waiting at the convergence of dielectric layers 7 and 9. At the proper instant, shearing blade 507 is driven forward by the piston rod of air cylinder 519 to sever structural insert 29. This instant of operation is shown in FIG. 13. Structural insert 29 is drawn between guide rollers 59 by the friction created between structural insert 29 and converging dielectric layers 7 and 9 and wound into the capacitor around arbor 117.
After structural insert 29 is in place in capacitor 1, drive rollers 75 are withdrawn from contact with capacitor electrode 15 and common electrode 11. Motor 805 is then energized to run at full speed -- approximately 1600 rpm. As previously explained, the initial capacitor windings are now sufficiently stable to prevent collapse of capacitor 1 when it is stripped off arbor 117. Also, because drive rollers 75 are no longer in contact with capacitor electrode 15 and common electrode 11, no unnecessary drag is placed on these fragile electrodes.
After a predetermined number of arbor 117 rotations, the time to insert tabs 23 and 27 arrives. The angular location of these tabs with respect to each other and tab 25 is critical. Therefore, their insertion is closely regulated.
Shortly before tabs 23 and 27 are inserted, drive assemblies 89 associated with foil rolls 43 and 45 are energized, causing the respective drive rollers 91 to drive tab webs 17 and 21. Tab webs 17 and 21 are driven until photodetector assemblies 105 associated with each drive assembly 89 sense tabs 23 and 27, respectively. The associated drive rollers 91 are locked, leaving the leading edges of their associated tab webs in slip engagement with the converging common or capacitor electrode and dielectric layer.
When sufficient time has elapsed for the tab webs to have assumed a position with their tabs beneath photodetector assemblies 105, tab sensing mechanism 201 is activated. As previously described, tab sensing mechanism detects the presence of tab 25 when it is directly in front of and closest to phototransistor 203. When tab 25 reaches this position, this information is conveyed to the central timing means. The central timing means, after a predetermined delay, causes reciprocating cutters 99 associated with tab webs 17 and 21 to be energized, severing tab webs 17 and 21 from tab rolls 43 and 45, and allowing them to be drawn into capacitor 1. Because of the previously described offset of the leading edge of tab web 17 and tab web 21, tab web 17 enters capacitor 1 before tab web 21, and tabs 23 and 27 are properly displaced from each other and tab 25.
After the predetermined lengths of capacitor electrode 15 and common electrode 11 have been drawn from their respective supply rolls 39 and 41, they must be severed from their supply rolls. Motor 805 is first slowed and then momentarily deenergized, resulting in a momentary halt of all paper and foil movement. Drive rollers 75 and idler rollers 77 are moved into contact with capacitor electrode 15 and common electrode 11, motor 805 is reenergized to operate at jog speed, and rotary cutters 79 associated with capacitor electrode 13 and common electrode 11 are energized, severing common electrode 11 and capacitor electrode 15. As previously described, this procedure permits drive rollers 75 and idler rollers 77 to grasp stationary electrodes 11 and 15 and avoid damage to those electrodes that could be caused by contact between non-synchronous surfaces.
After common electrode 11 and capacitor electrode 15 have been wound around arbor 117, and after a predetermined number of additional rotations of arbor 117, which deposits additional layers of dielectric layers 3-9 on capacitor 1, motor 805 is again deenergized. This causes arbor 117 to halt its rotation.
Transport means 615 is then energized. Air cylinders 623 and 625 cause piston rods 627 and 629, respectively, to carry clamps 631 toward each other to firmly grasp dielectric layers 3-9. Any alignment difficulties between clamps 631 are automatically corrected by rubber cushions 635.
Dielectric layer severing mechanism 619 is then energized. Air cylinder 663 causes piston rod 665 to extend, carrying serrated blade 667 into and through dielectric layers 3-9.
Subsequently, motor 805 is reenergized at jog speed to rotate arbor 117. Capacitor sealing means 617 is energized, causing cylinder 655 and its covering cork cylinder 657 to contact capacitor 1 and wet capacitor 1's outer surface. This is shown in FIG. 14. The moisture imparted to capacitor 1 by wet cork cylinder 657 causes the outer layers of dielectric layers 3-9 to adhere to each other.
Capacitor sealing means 617 is then deenergized, withdrawing cylinder 655 from capacitor 1. Subsequently, motor 805 is deenergized and pawl 809 is rotated into position to engage detents 807. Motor 805 is energized, rotating pulley 801 to engage one of the detents 807. This halts the rotation or arbor 117 with slot 123 in a vertical orientation.
Arbor 117 is then moved axially towards its retracted position by the piston rod 131 receding into air cylinder 133. As arbor 117 withdraws, the rear flat surface of capacitor 1 bears against stripper washer 159. Thus, stripper washer 159 forces capacitor 1 off arbor 117. Because of the close clearance between stripper washer 159 and arbor 117, none of the inner windings of capacitor 1 can be pulled between stripper washer 159 and arbor 117, preventing "telescoping" of capacitor 1.
Eventually, arbor 117 is completely withdrawn from capacitor 1, allowing capacitor 1 to fall onto capacitor conveying means 669. Belt 671 carries capacitor 1 to ramp 673. Capacitor 1 is stopped from rolling down ramp 673 by gate 675.
Near the end of the cycle drive assemblies 73 and drive assembly 301 are energized. They drive electrodes 11 and 13 and structural insert 29 to the position which they assume at the beginning of the next cycle. That is, electrodes 11 and 13 are driven into converging dielectric layers 5 and 9 and dielectric layers 3 and 7, respectively, at guide rollers 59.
The leading edge of structural insert 29 is fed through guide 313 and knife means 501. Structural insert 29 is then guided into channel 503 by tongue 327 and through knife means 501 to a point around guide rollers 59, where dielectric layers 7 and 9 converge. Cables 76 engage brake drum 80 and drive wheel 303 is locked to prevent electrodes 11 and 13 and structural insert 29 from feeding further by means of the frictional pull exerted by dielectric layers 3-9.
Capacitor 1 waits at gate 675 until the next cycle. When dielectric layer severing means 619 is operated, air cylinder 677 causes gate 675 to fall, allowing capacitor 1 to roll to the bottom of ramp 673.
While the invention has been particularly shown and described with reference to a preferred embodiment, it will be understood by those skilled in the art that changes in form and details, some of which have been described, may be made without departing from the spirit and scope of the invention.
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An automatic capacitor winding machine including a photoelectric device for sensing the position of a capacitor tab which is rotated by a rotating arbor is disclosed. The sensing device is characterized by a light source providing a light-beam directed along a line which lies in a plane perpendicular to the axis of rotation of the arbor. The tab crosses the line along which the light-beam is directed only twice. The width of the light-beam is greater than the width of the tab at the line crossing nearest the light source. A photoelectric detector is positioned to receive light directed along the line and it is responsive to light impinging thereon. The detector has an angle of light acceptance such that the light-beam is prevented from impinging on the detector only when the tab is at the line crossing which is nearest to the light detector.
This abstract is not to be taken either as a complete exposition or as a limitation of the present invention. However, the full nature and extent of the invention is discernible only by reference to and from the entire disclosure.
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BACKGROUND OF THE INVENTION
1. Field Of The Invention
This invention concerns an improved thermocouple for the temperature measurement of hot gases produced by the partial oxidation of ash-containing liquid hydrocarbonaceous and/or solid carbonaceous fuels. More specifically, it concerns a high temperature slag resistant thermocouple sheath.
2. Description Of The Prior Art
Thermocouples are used for measuring temperature in the well-known high temperature partial oxidation system for producing synthesis gas, reducing gas, and fuel gas. Thermocouples are pairs of insulated wires of dissimilar metals which are connected at both ends. When the two junctions of the wires e.g. T 2 and T 1 are at different temperatures, a difference in electrical potential exists between them. The thermal electromotive force (e.m.f) is a measure of the difference in temperature between T 2 and T 1 . A voltage-measuring instrument placed in the thermocouple circuit will measure temperature. For example, a sensitive high-temperature thermocouple consisting of platinum-platinum 10% rhodium will generate an e.m.f. of 9.457 millivolts and 17.339 millivolts when the differences between the hot junction and the cold junction in degrees F are respectively 1800 and 3000. Other pairs of metals e.g. chromel-alumel and iron-constantan are used to measure lower temperatures.
A corrosive atmosphere prevails during the operation of a high temperature partial oxidation gasifier. Any unprotected thermocouple in this atmosphere will be attacked and rendered useless, and especially when iron is present in the reaction zone. Various metals, alloys and refractory materials have been used in the past to form thermocouple protective sheaths. However, these materials were found to be unsuitable for long-time operation in partial oxidation systems where the temperature at various locations exceeds 1000° F. Impurities in liquid hydrocarbonaceous fuels and solid carbonaceous fuels, especially iron, readily attack thermocouples. Some noble metals e.g. platinum were found to be a sink for iron. Daily replacement of thermocouple sheaths made from these materials was not unusual. Iron-containing materials e.g. iron oxide are a major additive component in the gasification of fuels such as heavy liquid hydrocarbonaceous fuel and/or solid carbonaceous fuel that already contain iron, vanadium and nickel impurities. See related U.S. Pat. No. 4,668,428, which is incorporated herein by reference.
In coassigned U.S. Pat. No. 4,776,705, which is incorporated herein by reference, a thermocouple is enclosed in a noble metal protective sheath which in turn is inserted inside a multi-segment refractory thermowell. An annular space formed between the outside surface of the sheath and the inside surface of the thermowell is continuously purged with an oxidizing gas or gaseous mixture. Gasification products from the residual slag, which are normally in a form that react with and destroy the thermocouple wires, are neutralized or oxidized within the annular space by reaction with the purge gas mixtures. In contrast, advantageously by the subject invention, the aforesaid purge gas is eliminated, during the partial oxidation reaction, temperature measurments are more accurate, and the design of the thermocouple is simplified at a significant cost savings.
SUMMARY OF THE INVENTION
Briefly, this invention concerns a protective metal sheath for enclosing a thermocouple. The sheath is made from a continuous binary alloy consisting of about 30 to 70 wt. % of palladium and the remainder is silver. The thermocouple is used for measuring the high temperatures e.g. about 1000° F. to 2400° F. that are produced in the partial oxidation system wherein an ash-containing liquid hydrocarbonaceous and/or solid carbonaceous fuel is reacted by partial oxidation with a free-oxygen containing gas in the presence of a temperature moderator. A gaseous stream comprising H 2 , CO, CO 2 and at least one member from the group consisting of H 2 O, N 2 , H 2 S, COS, Ar, and CH 4 , as well as slag containing free metal is produced in the gasifier. Without said metal protective sheath, the thermocouple would be attacked and rendered useless by contact with metal constituents found in the slag, e.g. iron, vanadium. Further, hydrogen from the product gas passes through the protective Pd-Ag alloy sheath, and converts any oxides of vanadium in the +5 oxidation state to noncorrosive oxides of vanadium in the lower oxidation states.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a segmentary view in cross-section of a portion of a reactor wall in which a thermocouple and thermowell are installed.
DESCRIPTION OF THE INVENTION
Gaseous mixtures comprising H 2 , CO, CO 2 and at least one member from the group consisting of H 2 O, N 2 , H 2 S, COS, Ar, and CH 4 , along with particulate carbon ash and/or molten slag are known by the names synthesis gas, fuel gas, and reducing gas depending on such factors as chemical composition and end use. These gas mixtures are most commonly prepared by the well-known partial oxidation process in the reaction zone of a free-flow, down-flowing vertical refractory lined steel pressure vessel, such as shown and described in coassigned U.S. Pat. No. 2,818,326 which is incorporated herein by reference. The feed to the gasifier is an ash-containing heavy liquid hydrocarbonaceous fuel selected from the group consisting of virgin crude, residua from petroleum distillation and cracking, petroleum distillate, reduced crude, liquid hazardous and non-hazardous waste materials, whole crude, coal derived oil, shale oil, tar sand oil, and mixtures thereof. Alternatively, the feed to the gasifier may be dry feeds or liquid slurries of an ash-containing solid carbonaceous fuel selected from the group consisting of coal, such as anthracite, bituminous, subbituminous; coke from coal; lignite; residue derived from coal liquifaction; oil shale; tar sands; petroleum coke; asphalt; pitch; particulate carbon (soot), solid carbon-containing waste materials e.g. sewage, and mixtures thereof.
The feed is introduced preferably downwardly, into the reaction zone by way of an annular passage e.g. intermediate in a burner mounted in the top of the gasifier. A suitable annulus type burner is shown in coassigned U.S. Pat. No. 2,928,460, which is incorporated herein by reference. Simultaneously, a stream of free-oxygen containing gas with, or without a temperature moderator e.g. H 2 O, CO 2 is introduced into the reaction zone by way of at least one passage in said burner e.g. central and/or outer passages. The free-oxygen containing gas is selected from the group consisting of air, oxygen-enriched air i.e. greater than 21 mole % oxygen, and substantially pure oxygen i.e. greater than 95 mole % oxygen. The atomic ratio of free-oxygen in the oxidant to C in the feedstock is in the range of about 0.7 to 1.5, such as about 0.80 to 1.2. The H 2 O to fuel weight ratio is in the range of about 0.3 to 1.0, such as about 0.5 to 0.8.
The feed streams passing through the burner impinge downstream from the face of the burner and an autogenous reaction takes place at a temperature in the range of about 1700° F. to 2650° F. and a pressure in the range of about 5 to 250 atmospheres to produce a raw stream of synthesis gas, reducing gas, or fuel gas depending on the chemical composition of the gas. While all of these gases comprise H 2 +CO, the H 2 /CO mole ratio is controlled in synthesis gas as required for downstream catalytic synthesis of specific chemicals. Reducing gas generally has a greater H 2 /CO mole ratio. Fuel gas contains a greater amount of CH 4 and has a higher specific heat.
Temperatures in the range of about 1000° F., to 2400° F., which occur at various locations in the partial oxidation gasification system, may be measured by thermocouples containing the subject invention comprising an improved palladium-silver alloy protective sheath. The thermocouples are fabricated from commercially available noble metal thermocouple wire pairs, such as type B platinum/rhodium wire pairs. Except where the pairs of wires are joined to each other at the hot and cold junctions, each wire is electrically insulated from the other and from said alloy protective sheath by a high temperature ceramic material, such as alumina or magnesia. The pairs of wires are enclosed in the palladium-silver alloy sheath which has a thickness of about 0.005" to 0.10". This sheath is resistant to attack from the slag, and in particular, free metals in the slag e.g. Fe.
Advantageously, during gasification hydrogen in the process gas stream on the outside of the protective sheath passes through the walls of the Pd-Ag protective alloy sheath and provides a reducing atmosphere around the thermocouple wire pairs within the protective sheath. Any oxides of vanadium in the +5 oxidation state which are highly corrosive to the thermocouple wires and the alloy sheath, are reduced by said hydrogen-containing gas to non-corrosive oxides of vanadium in the lower oxidation states e.g. +4, +3, +2. Advantageously, the hydrogen comes from the synthesis gas that is being produced in the gasifier at no additional cost. Further, during operation no pumping equipment is needed to introduce the hydrogen into the thermocouple assembly.
The melting point of the Pd-Ag alloy protective sheath controls the use of the improved thermocouple for measuring temperatures in the range of about 1000° F. to 2400° F. For example, they may be used in the following places:
1. In the lower half of the partial oxidation gasifier above and below the central outlet located in the bottom of the gasifier. Note that a quench ring attached to the bottom of the gasifier will cool the bottom wall of the vertical gasifier, and the central effluent gas discharge passage. See coassigned U.S. Pat. No. 4,801,307, which is incorporated herein by reference.
2. In a secondary reaction zone or plenum chamber located downstream from the gasifier. See U.S. Pat. No. 4,778,484, which is incorporated herein by reference.
The various parts, their functions, and their interrelationship in the novel thermocouple disclosed, are most readily understood by referring to FIG I. Said Figure shows the invention installed in the combustion chamber of a typical free flow vertical reactor used for producing a usable gas by the partial oxidation of coal. One such reactor is shown and described in U.S. Pat No. 4,466,808. The raw synthesis gas containing entrained molten slag flows down the inside passage 12 of the gasifier. Molten slag 15 deposits out on the inside walls 14 of the refractory lining.
The downstream tips of the noble metal wires 26 and 27 are joined at the hot thermocouple junction 28. The upstream tips of the wires are joined at the cold thermocouple junction (not shown). The wires are surrounded by the Pd-Ag alloy protective sheath 24 which is closed adjacent to the hot thermocouple junction end. Except for being permeable to hydrogen, the sheath forms an essentially gas tight housing. The upstream ends of the thermocouple wires 26 and 27 extend past the back end of the protective sheath 24 and pass through a pressure sealing fitting 25. A plug 31 formed of high temperature epoxy and/or other high temperature cement defines a gas tight seal at the upstream end of the protective sheath. The pressure seal fitting contacts a bushing which fits into a removable threaded end cap 22. The thermocouple assembly is passed in succession straight through a threaded flanged nozzle 19 which mates with flanged inlet nozzle 18 that is attached to the outer steel wall 11 of the pressure vessel reactor 10, then through a hole in the steel wall of the pressure vessel, and then through a hole in refractory 8-9 which lines the inside wall of the pressure vessel. For example, one or more thermocouples may be installed near the bottom outlet of the reaction zone.
The thermocouple assembly is held in place by screwing together the threaded end cap 22 and the threaded flanged nozzle 2I. Mating flanges which are bolted or clamped together, also my be used. The tip of the metal alloy protective sheath 24 is retracted about 1/2" to 3" from the face of the steel wall of the pressure vessel in which it is installed, or when present from the face of the refractory lining the inside steel wall of the pressure vessel. For a more detailed description and drawing of a thermocouple, reference is made to coassigned U.S. Pat. No. 4,776,705, which is incorporated herein by reference. However, this reference does not teach applicants' improved Pd-Ag protective sheath 24. Further, it specifies the introduction of an additional purge gas during partial oxidation into a thermowell.
In another embodiment, a refractory thermowell 32 surrounds the previously described sheathed thermocouple. The thermowell may be made fron magnesia, alumina, chrome-magnesia, high chrome, or other high density low porosity refractory. Its purpose is to further protect the thermocouple and the alloy sheath from contact with elements from the slag during operation of the gasifier. The tip 16 of said thermowell may be retracted about 0 to 11/2" from the face 14 of the refractory 9 lining the inside steel wall of the pressure vessel.
In one embodiment, during shutdown or startup of the gasifier when very little hydrogen-containing gas is in the system, the gasifier has an oxidizing atmosphere. A separate stream of hydrogen-containing gas e.g. pure H 2 , synthesis gas is pumped into the elongated contiguous annular space 38 between the outside of the alloy protective sheath 24 and the inside of the thermowell 32. The hydrogen-containing gas will then permeate the protective alloy sheath By this means, any oxides of vanadium in the +5 oxidation state which may be present are reduced to the lower oxidation states +4, +3, +2. Attack of the thermocouple wires and alloy sheath by oxides of vanadium in the +5 oxidation state is thereby prevented. Reference is made to coassigned U.S. Pat. No. 4,776,705, which is incorporated herein by reference, for a suitable arrangement for pumping the subject hydrogen-containing gas instead of an oxidizing gas into the annular space between the subject alloy protective sheath and the thermowell. Further, see FIG. 1 reference numbers 38 to 43 of U.S. Pat. No. 4,776,705 and the drawing.
EXAMPLE
The following examples are offered as a better understanding of the present invention, but the invention is not to the construed as limited thereto.
A 500 milligram sample of slag from the partial oxidation of Pittsburgh #8 coal by the Texaco Coal partial oxidation Process at a temperature of about 2400° F. and a pressure of about 32 atmospheres was introduced into a platinum crucible. The crucible containing the slag was heated for 18 hrs at a temperature of 2400° F. and then quenched in water. Chemical analysis of the slag specimen (Sample No. 1) and the platinum crucible (Sample No. 2) after being quenched are shown in Table I below.
TABLE I______________________________________Heating Slag From Pittsburg No. 8Coal In Pt. Crucible SAMPLE NO. 2SAMPLE NO. 1 METAL INOXIDES IN SLAG - WT. % CRUCIBLE - WT. %______________________________________Pt 4.92 72Fe 22.50 28Na 1.32 --Mg 0.93 --Al 20.78 --Si 41.49 --S 2.0 --K 0.39 --Ca 3.35 --Mn 0.98 --______________________________________
The experiment was repeated using a crucible made from 65 wt. % palladium and the remainder silver. Chemical analysis of the slag (Sample No. 3) and the Pd-Ag crucible (Sample No. 4) after being quenched are shown in Table II below.
TABLE II______________________________________Heating Slag From Pittsburgh No. 8Coal In Pd-Ag Crucible SAMPLE NO. 4SAMPLE NO. 3 METAL INOXIDES IN SLAG - WT. % CRUCIBLE - WT. %______________________________________Pd 0.00 65Ag 0.00 35Fe 50.41 --Na 0.96 --Mg 0.97 --Al 9.92 --Si 32.00 --S 0.00 --K 0.09 --Ca 4.57 --Mn 0.47 --______________________________________
The experiment was repeated using a crucible made from 65 wt. % palladium and the remainder silver. In addition, the feed to the partial oxidation gasifier was coal in admixture with an iron-containing additive. Chemical analyses of the slag (Sample No. 5) and the Pd-Ag crucible (Sample No. 6) after being quenched are shown in Table III below.
TABLE III______________________________________Heating Slag From Pittsburgh No. 8Coal In Pd-Ag Crucible SAMPLE NO. 6SAMPLE NO. 5 METAL INOXIDES IN SLAG - WT. % CRUCIBLE - WT. %______________________________________Pd 0.00 65Ag 0.00 35Fe 73.23 --Na 0.98 --Mg 1.03 --Al 15.29 --Si 2.90 --S 6.00 --K 0.10 --Ca 0.32 --Mn 0.15 --______________________________________
Chemical analysis of the slag and Pt crucible, as shown in Table I (Sample Nos. 1 and 2) and as supported by visual microscopic examination of the Pt crucibles shows very severe interaction takes place between the platinum crucible and the slag. Further, platinum is shown to be a sink for iron. In contrast, there is no interaction between the molten slag and the palladium-silver crucible, as shown in Table II (Sample Nos. 3 and 4), Table III Sample Nos. 4 and 5, and by visual microscopic examination. Further, Pd-Ag alloy is not a sink for Fe, either with or without an iron-containing additive.
Various modifications of the invention as herein before set forth may be made without departing from the spirit and scope thereof. Therefore, only such limiations should be made as are indicated in the appended claims.
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This invention pertains to an improved high temperature slag resistant thermocouple sheath for protecting thermocouples used to measure the temperature of synthesis gas, reducing gas, or fuel gas produced by the partial oxidation of ash-containing liquid hydrocarbonaceous and/or solid carbonaceous fuels. The protection thermocouple sheath is made from a continuous binary alloy consisting of about 30 to 70 wt. % of palladium and the remainder silver. It may be used over a temperature range of about 1000° F. to 2400° F.
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CROSS REFERENCE TO RELATED APPLICATIONS
This application is a continuation-in-part application of U.S. patent application Ser. No. 11/892,188, filed Aug. 21, 2007, and entitled “METHOD OF MAKING AND ADMINISTERING QUINOLINE DERIVATIVES AS ANTI-CANCER AGENTS, and claims the benefit of (i) PCT/CN2008/072092, filed Aug. 21, 2008, which claims benefit of U.S. patent application Ser. No. 11/892,188, filed Aug. 21, 2007, (ii) Chinese Pat. Appl. No 200880110440.5, filed Aug. 21, 2008, now Chinese Pat. No. 101868447; (iii) Japanese Pat. Appl. No. 2010-521286, filed Aug. 21, 2008, now Japanese Pat. No. 5232233, (iv) European Pat. Appl. No. 08784083.1, filed Aug. 21, 2008, now European Pat. No. 2188259, and (v) U.S. Provisional Pat. Appl. Ser. No. 61/425,767, filed Dec. 22, 2010, the contents of which are incorporated herein in their entireties by reference.
FIELD OF THE INVENTION
This invention relates to a novel genus of compounds useful as anti-cancer agents. Particularly, it relates to a group of substituted quinoline derivatives which show potent anti-cancer effects.
BACKGROUND OF THE INVENTION
Substituted quinoline-type alkaloids are known for possessing interesting biological activities. For example, 8-hydroxyquinoline derivatives were reported to possess activities against (i) Alzheimer's disease, (ii) rat mesenchymal stem cells (rMSCs) proliferation and (iii) antifungal properties. The compound, 8-aminoquinoline (sitamaquine), has been suggested to be a candidate agent for treating visceral leishmania leishmaniasis. The 8-hydroxyquinoline and its derivatives have been reported to possess good antifungal properties and can help the treatment of neurodegenerative disease.
Asymmetric hydrogenation offers a new method for structural modification of this compound type to produce new chiral structural moiety and associated bioactivity. Zhou, Chan and others reported their effort in the asymmetric production of chiral tetrahydroquinoline with high enantioselectivities. However, there is no known report of the substituted quinoline-type alkaloids of the present invention that are useful for cancer treatment with good solubility and acceptable cell toxicity.
SUMMARY OF THE INVENTION
The present invention provides quinoline derivatives of formula I-IV and their salts for anti-tumor activities.
where A, B, C, D and W, X, Y and Z in the ring moieties is C, O, N, P, or S.
R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 and R 8 are each independently H, alkyl or substituted alkyl, alkenyl or substituted alkenyl, alkoxy or substituted alkoxy, hydroxyl or substituted hydroxyl, amino or substituted amino, thio or substituted thio, sulfonyl or substituted sulfonyl, sulfinyl or substituted sulfinyl, sulfonylamino or substituted sulfonylamino, halo, SO 3 H, amine, CN, CF 3 , acyl or substituted acyl, aryl or substituted aryl, heterocyclyl or substituted heterocyclyl, alkoxy or substituted alkoxy, aldehyde or substituted aldehyde or substituted phosphine; COR a , CSR a and CONHR a where R a is H, alkyl or substituted alkyl, alkenyl or substituted alkenyl, hydroxyl or substituted hydroxyl, aryl or substituted aryl, optionally heterocyclyl ring or substituted heterocyclyl ring; OR b , SR b or NR b R c where R b and R c are H or independently each other, alkyl or substituted alkyl, alkenyl or substituted alkenyl, acyl or substituted acyl, heterocyclyl ring or substituted heterocyclyl ring, CN; C 1 to C 4 NR d R e , HCNNR d R e or HCNOR d where R d and R e are H or independently each other, alkyl or substituted alkyl, alkenyl or substituted alkenyl, acyl or substituted acyl, heterocyclyl ring or substituted heterocyclyl ring; SR f , OR f or NR f R g , where R f and R g are H or independently each other, alkyl or substituted alkyl, alkenyl or substituted alkenyl, acyl or substituted acyl, heterocyclyl ring or substituted heterocyclyl ring; SO 2 NR h R i where R h and R i are H or independently each other, alkyl or substituted alkyl, alkenyl or substituted alkenyl, acyl or substituted acyl, heterocyclyl ring or substituted heterocyclyl ring.
Preferably, the aforementioned A, B, C, D, W, X, Y and Z is each independently C or N. More preferably, the quinoline derivative of the present invention is the following formula:
wherein R 1 , R 2 and R 3 are each independently H or Br; R 5 , R 7 and R 5 are H; R 6 is selected from the group consisting of CH 3 , CH 2 CH 3 , OBn, CH 2 CH 2 Ph, CH 2 OH; and R 4 is a substituted phenyl group, OBn, OH or OAc wherein said phenyl group is of the following formula:
wherein Ra is COH 2 , Rb is H, and Rc is Ph, F, Cl, OCF 3 , CF 3 , CN, OMe or NO 2 ; or Ra is COH 2 , Rb is Ph, F, Cl, OCF 3 , CN, OMe or NO 2 , and Rc is H.
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 use, reference should be made to the drawings and the following description in which there are illustrated and described preferred embodiments of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows the results of the MTS assays for compounds (+)-2b and (−)-2b on the carcinoma cell lines compared with CDDP
FIG. 2 shows tumor volume change of subcutaneous KYSE150 xenografts with i.p. injection of (−) isomers of 2b and PEG control
DETAILED DESCRIPTION OF THE INVENTION
The term “alkyl or substituted alkyl” denotes such radicals as straight chain, branched chain or cyclic hydrocarbon groups with 1 to 10 carbon atoms. These alkyl groups are methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, cyclopropyl, cyclobutyl, cyclopentyl or cyclohexyl.
The term “alkenyl or substituted alkenyl” denotes such radicals as straight chain, branched chain or cyclic hydrocarbon groups with at least one C═C double bond. These alkenyl groups are vinyl, allyl, propenyl, butenyl, 2-butenyl, 3-butenyl, 1-pentenyl, 2-pentenyl, 3-pentenyl, 4-pentenyl, cyclopentenyl, 1-methyl-cyclopentenyl, 1-hexenyl, 2-hexenyl, 3-hexenyl, 4-hexenyl, 5-hexenyl, cyclohexenyl, 1-heptenyl, 2-heptenyl, 3-heptenyl, 4-heptenyl, 5-heptenyl, 6-heptenyl, 1-octenyl, cyclooctenyl, 1-nonenyl, 2-nonenyl, 3-nonenyl, 1-decenyl, 3-decenyl, 1,3-butadienyl, 1,4-pentadienyl, 1,3-cyclopentadienyl, 1,3-hexadienyl, 1,4-hexadienyl, 1,3-cyclohexadienyl, 1,4-cyclohexadienyl, 1,3-cycloheptadienyl, as well as the straight and branched chain of the trienes.
The term “acyl or substituted acyl” denotes such radicals as aromatic, aliphatic or heterocyclic acyl group, the example the acyl groups are carbamoyl, straight or branch chain alkanoyl, such as, formyl, acetyl, propanoyl, butanoyl, isopropanoyl, pentanoyl, hexnoyl, heptanoyl, octanoyl, nonanoyl, decanoyl, undecanoyl, dodecanoyl, tridecanoyl, tetradecanoyl, pentadecanoyl, hexadecanoyl, heptadecanoyl, octadecanoyl, nonadecanoyl; alkoxycarbonyl, such as, methoxycarbonyl, ethoxycarbonyl, tetr-butoxycarbonyl, tetr-pentyloxycarbonyl or heptyloxycarbonyl; cycloalkylcarbonyl, such as, cyclopropylcarbonyl, cyclobutylcarbonyl, cyclopentyl, carbonyl or cyclohexylcarbonyl; alkylsulfonyl, such as, methylsulfonyl or ethylsulfonyl; alkoxysulfonyl, such as, methoxysulfonyl or ethoxysulfonyl; aroyl, such as, benxoyl, toluoyl or naphthoyl; aralkanoyl, such as, phenylacetyl, phenylpropanoyl, phenylbutanoyl, phenylisobutyl, phenylpentanoyl, phenylhexanoyl, naphthylacetyl, naphthylpropanoyl, naphthylbutanoyl; aralkenoyl, such as, phenylpropenoyl, phenylpentenoyl, phenylhexenoyl, naphthylpropenoyl, naphthylbutenoyl, naphthylpentenoyl; aralkoxycarbonyl, such as, benzyloxycarbonyl; aryloxycarbonyl, such as, phenoxyacetyl, naphthyloxycarbonyl; aryloxyalkanoyl, such as, phenoxyacetyl, phenoxypropionyl; arycarbamoyl, such as, phenylcarbamoyl, arylthiocarbamoyl, such as, phenylthiocarbamoyl; arylglyoxyloyl, such as, phenylglyoxyloyl, naphthylglyoxyloyl; arylsulfonyl, such as, phenylsulfonyl, naphthylsulfonyl; heterocycliccarbonyl, heterocylclicalkanoyl, such as, thienylacetyl, thienylpropanoyl, thienylbutanoyl, thienylpentanoyl, thienylhexanoyl, thiazolylacetyl, thiadiazolylacetyl, or tetrazolylacetyl, heterocyclicalkenoyl, such as, heterocyclicpropenoyl, heterocyclicbutenoyl, heterocyclicpentenoyl or heterocyclichexenoyl or heterocyclicglyoxyloyl, such as, thiazolylglyoxyloyl thienyglyoxyloyl.
The term “aryl or substituted aryl” denotes such radicals as carbocyclic aromatic or heterocyclic aromatic system, such as, phenyl, naphthyl, tetrahydronaphthyl, indane or biphenyl. These systems may be unsubstituted of substituted by one or more groups, such as, halogen, haloalkyl, hydroxyl, alkoxy, carbonyl, amido, alkylamido, dialkylamido, nitro, amino, alkylamino, dialkylamino, carboxy, thio or thioalkyl.
The term “heterocyclyl ring or substituted heterocyclyl ring” refers to monocyclic or polycyclic heterocyclic groups containing at least one heteroatom, such as, N-containing saturated and unsaturated heterocyclic groups, for example, pyrrolidinyl, imidazolidinyl, piperidino, piperazinyl; pyrrolyl, pyrrolinyl, imidazolyl, pyrazolyl, pyridyl, pyrimidinyl, pyrazinyl, pyridazinyl, triazolyl, tetrazolyl; indolyl, isoindolyl, indolizinyl, benzimidazolyl, quinolyl, isoquinolyl, indazolyl, benzotriazolyl or tetrazolopyridazinyl; O-containing saturated and unsaturated heterocyclic groups, for example, pyranyl, furyl, oxazolyl, isoxazolyl, oxadiazolyl, morpholinyl, benzoxazolyl or benzoxadiazolyl; S-containing saturated and unsaturated heterocyclic groups, for example, thienyl, thiazolyl, thiadiazolyl, thiazolidinyl or thiazolidinyl.
The term “halo or halogen” refer to fluorine, chlorine, bromine or iodine atom which can be one or more halogen atoms.
The term “hydroxyl” refers to a hydrogen bond to an oxygen atom, the term “substituted hydroxyl” denotes a hydroxyl group substituted with one or more groups, such as, halogen, protected hydroxyl, cyano, nitro, alkyl or substituted alkyl, alkenyl or substituted alkenyl, acyl or substituted acyl, awl or substituted awl, heterocyclyl ring or substituted heterocyclyl ring, alkoxy or substituted alkoxy, acyloxy or substituted acyloxy, carboxy or protected carboxy, carboxymethyl or protected carboxymethyl, hydroxymethyl or protected hydroxymethyl, amino or protected amino, carboxamide or protected carboxamide.
The term “alkoxy or substituted alkoxy” refers to straight or branch chain oxo-containing atoms with alkyl, for example, methoxy, ethoxy, propoxy, butoxy, and tert-butoxy.
The term “thio or substituted thio” refers to radicals containing —SH or —S— group, for examples, methylthio, ethylthio, propylthio, butylthio, hexylthio.
The term “sulfonyl or substituted sulfonyl” refers to radicals containing —S(O) 2 — group, for examples, methylsulfonyl, ethylsulfonyl, propylsulfonyl, trifluoromethanesulfonyl, trichloromethanesulfonyl or other halogen-substituted alky- or aryl-sulfonyl.
The term “sulfinyl or substituted sulfinyl” refers to radicals containing —S(═O)-group, for examples, methylsulfinyl, ethylsulfinyl, butylsulfinyl, hexylsulfinyl.
Synthesis of Substituted Quinoline
a) 5,7-Dibromo-2-methylquinolin-8-ol (2a)
2-methyl-8-quinolinol 1a (1.6 g, 10 mmol) was dissolved in 150 mL MeOH. 1 ml Br 2 in MeOH was added into the solution dropwise. After completed reaction, Na 2 SO 3 was added and the product was extracted by DCM to give the crude product. The crude product was purified by silica gel column chromatography to give the pure product, 1 H-NMR (500 MHz, CDCl 3 ): δ 2.75 (s, 3H), 7.39 (d, 1H, J=8.5 Hz), 7.79 (s, 1H), 8.26 (d, 1H, J=8.5 Hz); 13 C-NMR (125 MHz, CDCl 3 ): δ 25.40, 104.23, 110.64, 124.60, 125.47, 133.30, 136.64, 138.63, 149.76, 159.46; HRMS (ESI): Calcd. for C 10 H 8 NOBr 2 [M+H] + , 315.8973. found 315.8981. Yield=64.4%.
b) 5,7-Dibromo-8-hydroxyquinoline-2-carbaldehyde (3a)
5,7-Dibromo-2-methylquinolin-8-ol 2a (950 mg, 3 mmol), selenium dioxide (418 mg, 3.8 mmol), 100 ml of pre-dried 1,4-dioxane, and 0.5 ml of water were mixed and stirred in a 500 mL round bottom flask. The resulting solution was refluxed for 24 h and the reaction was monitored until completion using TLC method. Then the mixture was filtered off, and the selenium metal was washed with DCM, and the combined filtrates were evaporated off under reduced pressure, the crude product was purified by silica gel chromatography to yield the pure product, 1 H-NMR (500 MHz, CDCl 3 ): δ 8.06 (s, 1H), 8.17 (d, 1H, J=8.5 Hz), 8.64 (d, 1H, J=8.5 Hz), 10.25 (s, 1H); 13 C-NMR (125 MHz, CDCl 3 ): δ 106.02, 111.08, 119.83, 129.23, 137.30, 138.63, 138.78, 150.97, 151.72, 192.32; HRMS (ESI): Calcd. for C 10 H 6 NO 2 Br 2 [M+H] + , 329.8765. found 329.8765. Yield=98.0%.
c) 5,7-Dibromo-1,2,3,4-tetrahydro-2-methylquinolin-8-ol (2b)
A mixture of [Ir(COD)Cl] 2 (1.0 mg, 0.0015 mmol) and the P-Phos (2.1 mg, 0.0032 mmol) or other C 2 -symmetric bidendate chiral diphosphines ligands in dried solvent (e.g. THF) (1.0 mL) was stirred at room temperature for 30 minutes in a glovebox. The mixture was transferred by a syringe to stainless steel autoclave, in which I 2 (4 mg, 0.015 mmol) and 5,7-dibromo-2-methylquinolin-8-ol 2a (95 mg, 0.3 mmol) in 0.5 mL dried solvent were placed beforehand. The hydrogenation was performed at room temperature under H 2 for 20 h. After carefully releasing the hydrogen, the reaction mixture was quenched with saturated sodium carbonate solution (2.0 mL) for 15 minutes. The aqueous layer was extracted with EA (3×3 mL). The combined organic layer was dried with sodium sulfate and concentrated in vacuo to give the crude product. Purification by a silica gel column eluted with hexane/EA gave the pure product. The enantiomeric excesses (ee) were determined by HPLC with chiral column, 1 H-NMR (500 MHz, CDCl 3 ): δ 1.26 (d, 3H, J=6.0 Hz), 1.53-1.61 (m, 1H), 1.96-2.01 (m, 1H), 2.59-2.66 (m, 1H), 2.80-2.85 (m, 1H), 3.35-3.39 (m, 1H), 6.96 (s, 1H); 13 C-NMR (125 MHz, CDCl 3 ): δ 22.75, 27.89, 30.17, 46.90, 107.32, 116.76, 120.83, 120.97, 135.93, 138.33; HRMS (ESI): Calcd. for C 10 H 12 NOBr 2 [M+H] + , 319.9286. found 319.9261. HPLC (OJ-H, elute: Hexanes/i-PrOH=99/1, detector: 254 nm, flow rate: 1.0 mL/min), (S)=t 1 =19.08 min, (R) t 2 =20.45 min.
Optical pure 5,7-Dibromo-1,2,3,4-tetrahydro-2-methylquinolin-8-ol (+)-(2b)/(−)-(2b) was prepared by preparative HPLC with daicel OJ-H chiral preparative column (elute: Hexanes/i-PrOH=95/5, detector: 254 nm, flow rate: 5.0 mL/min), (S) t 1 =37.6 min, (R) t 2 =43.8 min.
d) 8-Hydroxy-2-quinolinecarboxaldehyde (4a)
8-Hydroxy-2-methylquinoline 1a (12.4 mmol, 1.97 g), selenium dioxide (15.8 mmol, 1.74 g), 300 ml of pre-dried 1,4-dioxane, and 1.5 ml of water were mixed and stirred in a 1-L round bottom flask. The resulting solution was refluxed for 24 h. The workup procedure can refer to step (b) in order to obtain pure, 1 H-NMR (500 MHz, C 6 D 6 ): δ 6.76-6.79 (m, 1H), 7.05 (d, 1H, J=4.0 Hz), 7.12 (s, 1H), 7.33 (d, 1H, J=9.0 Hz), 7.63 (d, 1H, J=9.0 Hz), 8.02 (s, 1H), 9.79 (s, 1H); 13 C-NMR (125 MHz, C 6 D 6 ): δ 111.81, 118.33, 118.49, 130.98, 131.35, 137.81, 138.54, 150.99, 154.19, 192.58; LRMS (ESI): 174.05 [M+H] + ; Melting point: 99.7° C.
e) 1,2,3,4-Tetrahydro-2-(hydroxymethyl)quinolin-8-ol (5b)
A mixture of 10% Pd/C (500 mg), 8-hydroxy-2-quinolinecarboxaldehyde (500 mg, 2.89 mmol), and acetic acid (10 ml) was stirred in an autoclave under 100 bar hydrogen pressure at room temperature for 20 h. The mixture was filtered through a short pad of Celite, which was subsequently washed with MeOH (20 ml). Hydrochloric acid was added, and the solvent was removed under reduced pressure to give the crude product. Purification by a silica gel column eluted with hexane/EA gave the pure product, 1 H-NMR (500 MHz, CDCl 3 ): δ 1.60-1.67 (m, 1H), 1.92-1.98 (m, 1H), 2.71-2.80 (m, 1H), 2.81-2.87 (m, 1H), 3.51-3.54 (m, 1H), 3.66-3.69 (m, 1H), 6.45-6.54 (m, 3H); 13 C-NMR (125 MHz, CDCl 3 ): δ 26.75, 27.59, 55.11, 67.92, 113.52, 119.16, 122.14, 124.57, 134.98, 146.30; HRMS (ESI): Calcd. for C 10 H 11 NO 2 Na [M+Na] + , 200.0687. found 200.0685.
Synthesis of Alkoxy-Substituted Quinaldine
To a solution of hydroxyl-substituted halogenated or non-halogenated quinoline (3 mmol), alkyl halide (RX, 3 mmol, where X=Br − or Cl) and K 2 CO 3 were stirred in 10 mL DMF. The reaction was run at room temperature and monitored by TLC. After the reaction was complete, the mixture was washed with Na 2 CO 3 and extracted with EA and then dried over anhydrous sodium sulfate. Then the solvent was removed under reduced pressure and the crude product was purified by silica gel column chromatography to give the pure product.
6-Propoxyquinoline (6a)
1 H-NMR (500 MHz, CDCl 3 ): δ1.03 (t, 3H, J=7.5 Hz), 1.79-1.86 (m, 2H), 3.96 (t, 2H, J=6.5 Hz), 6.98 (d, 1H, J=2.5 Hz), 7.25-7.27 (m, 1H), 7.31-7.34 (m, 1H), 7.94-7.96 (m, 2H), 8.70-8.71 (m, 1H); 13 C-NMR (125 MHz, CDCl 3 ): δ 11.12, 23.07, 70.31, 106.37, 121.82, 123.10, 129.89, 131.33, 135.23, 144.92, 148.36, 157.79; Yield=82.6%.
6-Butoxyquinoline (7a)
1 H-NMR (500 MHz, CDCl 3 ): δ 0.96 (t, 3H, J=7.5 Hz), 1.47-1.51 (m, 2H), 1.76-1.81 (m, 2H), 4.00 (t, 2H, J=7.0 Hz), 6.99 (d, 1H, J=3.0 Hz), 7.25-7.27 (m, 1H), 7.31-7.34 (m, 1H), 7.94-7.97 (m, 2H), 8.70-8.71 (m, 1H); 13 C-NMR (125 MHz, CDCl 3 ): δ 14.42, 19.85, 31.78, 68.52, 106.35, 121.82, 123.12, 129.90, 131.33, 135.23, 144.93, 148.36, 157.81; Yield=93.7%.
8-(2-(Piperidin-1-yl)ethoxy)-2-methylquinoline (8a)
1 H-NMR (500 MHz, CDCl 3 ): δ 1.46 (bs, 2H), 1.70 (bs, 4H), 2.71 (bs, 7H), 3.04 (bs, 2H), 4.34 (bs, 2H), 6.99 (d, 1H, J=7.0 Hz), 7.24 (d, 1H, J=9.0 Hz), 7.28-7.33 (m, 2H), 7.95 (d, 1H, J=8.5 Hz); 13 C-NMR (125 MHz, CDCl 3 ): δ 23.81, 24.88, 25.31, 54.46, 57.31, 64.31, 109.36, 120.26, 122.95, 125.94, 127.98, 136.58, 139.62, 153.83, 158.46; LRMS (ESI): 271.21 [M+H] +
8-(3-nitrobenzyloxy)-2-methylquinoline (9a)
1 H-NMR (500 MHz, CDCl 3 ): δ 2.82 (s, 3H), 5.52 (s, 2H), 7.00 (d, 1H, J=7.5 Hz), 7.32 (q, 2H, J=9.0 Hz), 7.39 (d, 1H, J=8.0 Hz), 7.54 (t, 1H, J=7.5 Hz), 7.89 (d, 1H, J=7.5 Hz), 8.02 (d, 1H, J=8.5 Hz), 8.16 (d, 1H, J=8.5 Hz), 8.44 (s, 1H); 13 C-NMR (125 MHz, CDCl 3 ): δ 26.45, 70.59, 111.57, 121.40, 122.60, 123.41, 126.07, 128.52, 130.22, 133.57, 136.78, 140.26, 140.73, 149.11, 154.02, 159.18; HRMS (ESI): Calcd. for C 17 H 15 N 2 O 3 [M+H] + , 295.1083. found 295.1078. Melting Point=94.4-95.2° C.; Yield=80.1%.
8-(4-nitrobenzyloxy)-2-methylquinoline (10a)
1 H-NMR (500 MHz, CDCl 3 ): δ 2.81 (s, 3H), 5.53 (s, 2H), 6.94 (d, 1H, J=7.5 Hz), 7.26-7.39 (m, 3H), 7.69 (d, 2H, J=8.5 Hz), 8.02 (d, 1H, J=8.5 Hz), 8.22 (d, 2H, J=9.0 Hz); 13 C-NMR (125 MHz, CDCl 3 ): δ 26.40, 70.34, 111.18, 121.26, 123.38, 124.42, 125.60, 127.89, 128.46, 136.76, 140.56, 145.49, 148.05, 153.82, 159.10; HRMS (ESI): Calcd. for C 17 H 15 N 2 O 3 [M+H] + , 295.1083. found 295.1089. Melting Point=144.1-145.7° C.; Yield=50%.
8-(4-methoxybenzyloxy)-2-methylquinoline (11a)
1 H-NMR (500 MHz, CDCl 3 ): δ 2.80 (s, 3H), 3.80 (s, 3H), 5.38 (s, 2H), 6.90 (d, 2H, J=8.0 Hz), 7.03 (d, 1H, J=7.0 Hz), 7.26-7.34 (m, 3H), 7.45 (d, 2H, J=8.5 Hz), 8.00 (d, 1H, J=8.5 Hz); 13 C-NMR (125 MHz, CDCl 3 ): δ 25.95, 55.50, 70.86, 110.71, 114.18, 119.98, 122.75, 125.78, 127.96, 128.89, 129.46, 136.31, 140.32, 154.15, 158.36, 159.45; HRMS (ESI): Calcd. for C 18 H 18 NO 2 [M+H] + , 280.1338. found 280.1343. Melting Point=130.8-131.5° C.; Yield=67.3%.
8-(3-methoxybenzyloxy)-2-methylquinoline (12a)
1 H-NMR (500 MHz, CDCl 3 ): δ 2.81 (s, 3H), 3.79 (s, 3H), 5.44 (s, 2H), 6.84 (d, 1H, J=8.0 Hz), 7.01 (d, 1H, J=8.0 Hz), 7.08-7.11 (m, 2H), 7.15-7.38 (m, 4H), 8.01 (d, 1H, J=8.0 Hz); 13 C-NMR (125 MHz, CDCl 3 ): δ 26.42, 55.90, 71.43, 111.20, 112.85, 113.99, 119.71, 120.53, 123.21, 126.21, 128.39, 130.25, 136.74, 139.67, 140.73, 154.52, 158.81, 160.53; HRMS (ESI): Calcd. for C 18 H 18 NO 2 [M+H] + , 280.1338. found 280.1337. Melting Point=104.1-104.8° C.; Yield=86%.
4-((2-methylquinolin-8-yloxy)methyl)benzonitrile (13a)
1 H-NMR (500 MHz, CDCl 3 ): δ 2.81 (s, 3H), 5.49 (s, 2H), 6.93 (d, 1H, J=8.0 Hz), 7.28-7.39 (m, 3H), 7.63-7.67 (m, 4H), 8.03 (d, 1H, J=8.5 Hz); 13 C-NMR (125 MHz, CDCl 3 ): δ 26.03, 45.01, 70.15, 110.75, 111.72, 119.02, 120.80, 123.00, 125.64, 127.47, 128.08, 132.65, 136.39, 140.20, 143.09, 153.51, 158.71; HRMS (ESI): Calcd. for C 18 H 15 N 2 O [M+H] + , 275.1184. found 275.1187. Melting Point=124.1-125.3° C.; Yield=85.7%.
8-(biphenyl-3-ylmethoxy)-2-methylquinoline (14a)
1 H-NMR (500 MHz, CDCl 3 ): δ 2.82 (s, 3H), 5.53 (s, 2H), 7.05 (d, 1H, J=7.5 Hz), 7.26-7.35 (m, 4H), 7.41-7.46 (m, 3H), 7.50-7.54 (m, 2H), 7.59-7.61 (m, 2H), 7.78 (s, 1H), 8.01 (d, 1H, J=8.0 Hz); 13 C-NMR (125 MHz, CDCl 3 ): δ 26.01, 71.24, 110.87, 120.18, 122.81, 125.80, 125.92, 126.08, 126.74, 127.46, 127.58, 128.00, 128.96, 129.24, 136.33, 138.12, 141.20, 141.72, 154.15, 158.43; HRMS (ESI): Calcd. for C 23 H 20 NO [M+H] + , 326.1545. found 326.1557. Melting Point=89.8-99.4° C.; Yield=85.7%.
8-(4-(trifluoromethoxy)benzyloxy)-2-methylquinoline (15a)
1 H-NMR (500 MHz, CDCl 3 ): δ 2.81 (s, 3H), 5.43 (s, 2H), 6.99 (d, 1H, J=6.5 Hz), 7.22 (d, 2H, J=7.5 Hz), 7.29-7.37 (m, 3H), 7.56 (d, 2H, J=9.0 Hz), 8.01 (d, 1H, J=8.5 Hz); 13 C-NMR (125 MHz, CDCl 3 ): δ 26.00, 70.28, 110.72, 119.68, 120.43, 121.30, 121.31, 121.72, 122.88, 125.71, 128.02, 128.62, 136.21, 136.34, 140.26, 148.91, 153.84, 158.56; HRMS (ESI): Calcd. for C 18 H 15 NO 2 F 3 [M+H] + , 334.1055. found 334.1056. Melting Point=103.9-104.6° C.; Yield=73.1%.
8-(4-fluorobenzyloxy)-2-methylquinoline (16a)
1 H-NMR (500 MHz, CDCl 3 ): δ 2.80 (s, 3H), 5.40 (s, 2H), 6.99 (d, 1H, J=6.5 Hz), 7.05 (t, 2H, J=6.5 Hz), 7.28-7.36 (m, 3H), 7.48-7.51 (m, 2H), 8.01 (d, 1H, J=8.5 Hz); 13 C-NMR (125 MHz, CDCl 3 ): δ 25.98, 70.47, 110.75, 115.59, 115.76, 120.29, 122.83, 125.72, 128.00, 129.02, 129.09, 133.17, 136.33, 140.28, 153.92, 158.48, 161.61, 163.56; HRMS (ESI): Calcd. for C 17 H 15 NOF [M+H] + , 268.1138. found 268.1144. Melting Point=130-130.6° C.; Yield=80.5%.
8-(4-(trifluoromethyl)benzyloxy)-2-methylquinoline (17a)
1 H-NMR (500 MHz, CDCl 3 ): δ 2.82 (s, 3H), 5.50 (s, 2H), 6.95 (d, 1H, J=8.0 Hz), 7.26-7.37 (m, 3H), 7.61-7.65 (m, 4H), 8.02 (d, 1H, J=8.5 Hz); 13 C-NMR (125 MHz, CDCl 3 ): δ 26.01, 70.30, 110.72, 120.55, 122.55, 125.62, 127.16, 128.05, 130.09, 136.37, 140.23, 141.65, 153.69, 158.62; HRMS (ESI): Calcd. for C 18 H 15 NOF 3 [M+H] + , 318.1106. found 318.1118. Melting Point=130.8-131.5° C.; Yield=82%.
8-(4-chlorobenzyloxy)-2-methylquinoline (18a)
1 H-NMR (500 MHz, CDCl 3 ): δ 2.80 (s, 3H), 5.41 (s, 2H), 6.96 (d, 1H, J=6.5 Hz), 7.27-7.36 (m, 5H), 7.45 (d, 2H, J=8.5 Hz), 8.01 (d, 1H, J=8.5 Hz); 13 C-NMR (125 MHz, CDCl 3 ): δ 26.01, 70.35, 110.76, 120.36, 122.86, 125.70, 128.01, 128.52, 128.96, 133.64, 136.01, 136.34, 140.27, 153.82, 158.52; HRMS (ESI): Calcd. for C 17 H 15 NOCl [M+H] + , 284.0842. found 284.0841. Melting Point=118.7-119° C.; Yield=90.5%.
2-Methylquinolin-8-yl(7,7-dimethyl-2-oxobicyclo[2.2.1]heptan-1-yl)methanesulfonate (19a)
1 H-NMR (500 MHz, CDCl 3 ): δ 0.95 (s, 3H), 1.19 (s, 3H), 1.41-1.47 (m, 1H), 1.70-1.76 (m, 1H), 1.95 (d, 1H, J=18.5 Hz), 2.05-2.13 (m, 2H), 2.39-2.44 (m, 1H), 2.57-2.63 (m, 1H), 2.77 (s, 3H), 3.91 (d, 1H, J=15.5 Hz), 4.44 (d, 1H, J=15.0 Hz), 7.35 (d, 1H, J=8.5 Hz), 7.48 (t, 1H, J=8.0 Hz), 7.67 (d, 1H, J=7.5 Hz), 7.73 (d, 1H, J=8.0 Hz), 8.08 (d, 1H, J=8.5 Hz); 13 C-NMR (125 MHz, CDCl 3 ): δ 19.99, 20.32, 25.42, 25.66, 27.16, 42.75, 43.20, 48.12, 49.71, 58.68, 123.18, 123.92, 125.60, 127.00, 128.37, 136.42, 141.24, 145.50, 160.15, 214.64; HRMS (ESI): 374.1438 [M+H] + ; Yield=65%.
1-(4-fluorophenyl)-2-(2-methylquinolin-8-yloxy)ethanone (20a)
1 H-NMR (500 MHz, CDCl 3 ): δ 2.77 (s, 3H), 5.56 (s, 2H), 6.97 (d, 1H, J=7.5 Hz), 7.15 (t, 2H, J=8.5 Hz), 7.32 (t, 2H, J=7.5 Hz), 7.39 (d, 1H, J=8.0 Hz); 8.01 (d, 1H, J=8.0 Hz), 8.18-8.21 (m, 2H); 13 C-NMR (125 MHz, CDCl 3 ): δ 26.17, 72.88, 105.32, 111.38, 116.51, 121.49, 123.24, 125.94, 128.44, 131.77, 136.67, 140.37, 153.77, 158.88, 165.64, 167.68, 193.97; HRMS (ESI): Calcd. for C 18 H 15 NO 2 F [M+H] + , 296.1087. found 296.1090. Yield=77.7%.
5,7-Dibromo-8-ethoxy-2-methylquinoline (21a)
1 H-NMR (500 MHz, CDCl 3 ): δ 1.53 (t, 3H, J=7.0 Hz), 2.77 (s, 3H), 4.45 (q, 2H, J=7.0 Hz), 7.36 (d, 1H, J=8.5 Hz), 7.88 (s, 1H), 8.30 (d, 1H, J=8.5 Hz); 13 C-NMR (125 MHz, CDCl 3 ): δ 16.45, 26.13, 71.74, 116.44, 117.24, 123.93, 126.97, 133.12, 136.54, 144.09, 152.99, 160.44; HRMS (ESI): Calcd. for C 12 H 12 NOBr 2 [M+H] + , 343.9286. found 343.9288. Yield=83.5%.
2-(5,7-dibromo-2-methylquinolin-8-yloxy)-1-phenylethanone (22a)
1 H-NMR (500 MHz, CDCl 3 ): δ 2.54 (s, 3H), 5.79 (s, 2H), 7.30 (d, 1H, J=9.0 Hz), 7.48 (t, 2H, J=8.0 Hz), 7.58 (t, 1H, J=7.0 Hz), 7.89 (s, 1H), 8.13 (d, 2H, J=8.0 Hz), 8.27 (d, 1H, J=9.0 Hz); 13 C-NMR (125 MHz, CDCl 3 ): δ 25.53, 77.05, 115.78, 116.17, 123.94, 126.88, 129.04, 129.30, 133.22, 134.08, 135.67, 136.65, 142.63, 151.55, 159.92, 195.12; HRMS (ESI): Calcd. for C 18 H 14 NO 2 Br 2 [M+H] + , 433.9391. found 433.9398. Yield=87.7%.
Synthesis of 2,8-Bis(benzyloxy)quinoline and 1-Benzyl-8-(benzyloxy)quinolin-2(1H)-one
2,8-Bis(benzyloxy)quinoline (23a)
1 H-NMR (500 MHz, CDCl 3 ): δ 5.26 (s, 2H), 5.51 (s, 2H), 6.90 (d, 1H, J=9.0 Hz), 7.04 (d, 1H, J=8.0 Hz), 7.16-7.20 (m, 1H), 7.22-7.32 (m, 7H), 7.48 (q, 4H, J=8.0 Hz), 7.89 (d, 1H, J=9.0 Hz); 13 C-NMR (125 MHz, CDCl 3 ): δ 67.96, 71.60, 112.65, 113.70, 120.58, 124.21, 126.69, 127.52, 127.99, 128.09, 128.63, 128.72, 128.90, 137.66, 137.77, 138.68, 139.19, 153.56, 161.35; LRMS (ESI): 342.07 [M+H] + ; Yield=53.4%.
1-Benzyl-8-(benzyloxy)quinolin-2(1H)-one (24a)
1 H-NMR (500 MHz, CDCl 3 ): δ 4.88 (s, 2H), 5.94 (s, 2H), 6.79 (d, 1H, J=9.0 Hz), 6.90 (d, 2H, J=7.5 Hz), 7.02 (d, 1H, J=8.0 Hz), 7.06-7.19 (m, 7H), 7.26-7.31 (m, 3H), 7.69 (d, 1H, J=7.5 Hz); 13 C-NMR (125 MHz, CDCl 3 ): δ 49.70, 72.05, 115.22, 122.15, 122.33, 123.07, 123.52, 125.85, 126.28, 127.82, 128.37, 128.42, 128.83, 130.95, 136.14, 139.37, 140.14, 147.49, 163.80; LRMS (ESI): 342.07 [M+H] + ; Yield=31.4%.
Synthesis of 1-Acetyl-2-methyl-1,2,3,4-tetrahydroquinolin-8-yl acetate and 2-Methyl-1,2,3,4-tetrahydroquinolin-8-yl acetate
Add slowly 100 mg (0.6 mmol) of 1,2,3,4-tetrahydro-2-methylquinolin-8-ol into a preheated solution of ZnCl 2 (4%) (0.5 g anhydrous ZnCl 2 in 12.5 ml acetic anhydride) in a 50 ml round flask bottom which was attached with an air condenser. Then the mixture was heated on a water bath for another one hour. After the reaction was completed, cool the solution with cold water, and then pour into ice water (10 ml) and stir vigorously to assist the hydrolysis of unreacted acetic anhydride. Then the product was extracted with EA and dried over anhydrous sodium sulfate. The solvent was removed under reduced pressure and the crude product was purified by silica gel column chromatography to give the pure product.
2-Methyl-1,2,3,4-tetrahydroquinolin-8-yl acetate (25b)
1 H-NMR (500 MHz, CDCl 3 ): δ 2.50 (s, 3H), 2.73 (s, 3H), 7.30 (d, 1H, J=9.0 Hz), 7.40 (d, 1H, J=7.5 Hz), 7.46 (t, 1H, J=8.0 Hz), 7.67 (d, 1H, J=8.5 Hz), 8.05 (d, 1H, J=9.0 Hz); 13 C-NMR (125 MHz, CDCl 3 ): δ 21.23, 25.96, 31.15, 121.54, 122.89, 125.43, 125.80, 128.01, 136.22, 140.89, 147.24, 159.64, 170.21; LRMS (ESI): 202.09 [M+H] + ; Yield=91.1%.
1-Acetyl-2-methyl-1,2,3,4-tetrahydroquinolin-8-yl acetate (26b)
1 H-NMR (500 MHz, CDCl 3 ): δ 1.05 (d, 3H, J=6.5 Hz), 1.20-1.26 (m, 1H), 2.01 (s, 3H), 2.27 (s, 3H), 2.37-2.45 (m, 2H), 2.59-2.62 (m, 1H), 4.81 (q, 1H, J=7.5 Hz), 7.02 (d, 1H, J=8.5 Hz), 7.10 (d, 1H, J=7.5 Hz), 7.21 (t, 1H, J=8.0 Hz); 13 C-NMR (125 MHz, CDCl 3 ): δ 20.96, 21.40, 22.19, 27.28, 33.63, 49.52, 121.59, 124.99, 126.99, 131.13, 139.60, 145.68, 168.93, 170.93; LRMS (ESI): 270.10 [M+Na] +
Synthesis of 8-Benzyloxy Substituted Quinoline
To a solution of 8-(Benzyloxy)-2-methylquinoline (3 mmol, 790 mg) in 15 mL ether was added a 1.6M solution of n-butyllithium in hexane (3.5 mmol, 2.2 mL) at 0° C. over 30 minutes. This solution was allowed to warm to room temperature and stirred for 1 h. The above mixture, a solution of BnBr (3 mmol) in 15 mL ether was added dropwise over 15 minutes with vigorous stirring while the temperature was cooled to 0° C. The mixture was then stirred overnight and hydrolysed with a saturated aqueous ammonium chloride solution. The organic layer was separated and the aqueous layer was further extracted with ether (3×50 mL). The combined organic layers were washed with brine and dried over anhydrous sodium sulfate. The solvent was removed under reduced pressure and the crude product was purified by silica gel column chromatography to give the pure product.
8-(Benzyloxy)-2-ethylquinoline (27a)
1 H-NMR (500 MHz, CDCl 3 ): δ 1.43 (t, 3H, J=7.5 Hz), 3.10 (q, 2H, J=7.5 Hz), 5.47 (s, 2H), 7.02 (d, 1H, J=7.5 Hz), 7.30 (t, 2H, J=7.5 Hz), 7.36 (t, 4H, J=8.0 Hz), 7.54 (d, 2H, J=7.5 Hz), 8.04 (d, 1H, J=8.5 Hz); 13 C-NMR (125 MHz, CDCl 3 ): δ14.32, 32.62, 71.17, 110.97, 120.18, 121.49, 125.79, 127.18, 127.87, 128.24, 128.76, 136.47, 137.59, 140.32, 154.25, 163.34; LRMS (ESI): 264.10 [M+H] + .
8-(Benzyloxy)-2-phenethylquinoline (28a)
1 H-NMR (500 MHz, CDCl 3 ): δ 3.22 (t, 2H, J=7.0 Hz), 3.19 (t, 2H, J=7.5 Hz), 5.47 (s, 2H), 7.06 (d, 1H, J=7.5 Hz), 7.30 (t, 2H, J=7.5 Hz), 7.36 (t, 4H, J=8.0 Hz), 7.56 (d, 2H, J=7.5 Hz), 8.02 (d, 1H, J=8.5 Hz); 13 C-NMR (125 MHz, CDCl 3 ): δ 35.99, 41.03, 71.29, 111.22, 120.27, 122.22, 125.96, 126.16, 127.21, 127.90, 128.33, 128.59, 128.76, 128.83, 136.37, 137.59, 140.49, 141.98, 154.30, 161.05; HRMS (ESI): 340.17 [M+H] + ; Yield=47.8%.
Synthesis of Alcohol Protected Quinoline
To a stirred solution of 5,7-dibromo-8-hydroxyquinoline-2-carbaldehyde (200 mg, 0.60 mmol) in dry MeOH (20 ml), hydrochloride gas was bubbled at room temperature, after complete reaction the result mixture was stirring for overnight. Then MeOH was removed under reduced pressure to give the designed product 5,7-Dibromo-2-(dimethoxymethyl)quinolin-8-ol (29a) 1 H-NMR (500 MHz, CD 3 OD): δ 3.20 (s, 6H), 5.64 (s, 1H), 7.83 (d, 1H, J=8.5 Hz), 7.91 (s, 1H), 8.63 (d, 1H, J=9.0 Hz); 13 C-NMR (125 MHz, CD 3 OD): δ 103.68, 110.12, 112.02, 123.21, 129.38, 137.27, 137.56, 142.59, 151.35, 158.59; HRMS (ESI): Calcd. for C 12 H 12 NO 3 Br 2 [M+H] + , 375.9197. found 375.9184. Yield=88.2%.
Asymmetric Synthesis of 1,2,3,4-Tetrahydroquinoline
L*=Chiral P-Phos and its derivatives, C 2 -symmetric bidendate chiral diphosphines ligands or any other possible ligands; M=Any metal or non-metal complex.
A mixture of metal for example of [Ir(COD)Cl] 2 (1.0 mg, 0.0015 mmol) and the ligand (0.003 mmol) in dried solvent (1.0 mL) was stirred at room temperature for 30 minutes in a glovebox. The mixture was then transferred by a syringe to stainless steel autoclave, in which I 2 (4 mg, 0.015 mmol) and substrate (0.3 mmol) in 0.5 mL dried solvent were placed beforehand. The hydrogenation was performed at room temperature under H 2 for 20 h. After carefully releasing the hydrogen, the reaction mixture was quenched with saturated sodium carbonate solution (2.0 mL) for 15 minutes. The aqueous layer was extracted with EtOAc (3×3 mL). The combined organic layer was dried with sodium sulfate and concentrated in vacuo to give the crude product. Purification by a silica gel column eluted with hexane/EtOAc gave the heterocyclic compound in pure state. The enantiomeric excesses (ee) were determined by chiral HPLC with chiral column (OJ-H, OD-H or OJ) [21].
8-(2-(Piperidin-1-yl)ethoxy)-1,2,3,4-tetrahydro-2-methylquinoline (8b)
1 H-NMR (500 MHz, CDCl 3 ): δ 0.1 (s, 2H), 1.18 (d, 6H, J=6.5 Hz), 2.11 (s, 4H), 2.53 (bs, 3H), 2.64-2.69 (m, 2H), 2.72-2.81 (m, 3H), 3.30-3.34 (m, 1H), 4.08 (bs, 2H), 6.46 (t, 1H, J=8.0 Hz), 6.56 (t, 2H, J=8.5 Hz); 13 C-NMR (125 MHz, CDCl 3 ): δ 22.84, 24.20, 25.82, 26.60, 26.73, 30.26, 46.89, 55.03, 58.05, 66.03, 70.84, 109.38, 115.89, 121.57, 122.11, 135.24, 145.28; LRMS (ESI): 275.21 [M+H] + ; 47% ee; HPLC(OD-H, elute: Hexanes/i-PrOH=90/10, detector: 254 nm, flow rate: 1.0 mL/min), (S) t 1 =8.3 min, (R) t 2 =7.1 min.
8-(Benzyloxy)-1,2,3,4-tetrahydro-2-methylquinoline (30b)
1 H-NMR (500 MHz, CDCl 3 ): δ 1.25 (d, 3H, J=6.5 Hz), 1.62-1.68 (m, 1H), 1.93-1.98 (m, 1H), 2.75-2.80 (m, 1H), 2.85-2.89 (m, 1H), 3.39-3.43 (m, 1H), 4.21 (bs, 1H), 5.08 (q, 2H, J=6 Hz), 6.56 (t, 1H, J=8.0 Hz), 6.68 (q, 2H, J=8.0 Hz), 7.35 (t, 1H, J=7.0 Hz), 7.42 (t, 2H, J=8.0 Hz), 7.46 (d, 2H, J=7.0 Hz); 13 C-NMR (125 MHz, CDCl 3 ): δ 23.25, 27.04, 30.70, 47.34, 71.04, 109.63, 116.31, 121.96, 122.50, 128.29, 128.57, 129.20, 135.47, 138.06, 145.88; HRMS (ESI): Calcd. for C 17 H 20 NO [M+H] + , 254.1545. found 254.1542; [α] D 18 =+321 (c 0.0048, CHCl 3 ), 93% ee; HPLC (OD-H, elute: Hexanes/i-PrOH=90/10, detector: 254 nm, flow rate: 1.0 ml/min), t 1 =5.4 min (minor), (R) t 2 =6.7 min (major).
8-(3-Nitrobenzyloxy)-1,2,3,4-tetrahydro-2-methylquinoline (9b)
1 H-NMR (500 MHz, CDCl 3 ): δ 1.28 (d, 3H, J=6.5 Hz), 1.61-1.68 (m, 1H), 1.95-2.00 (m, 1H), 2.76-2.81 (m, 1H), 2.85-2.92 (m, 1H), 3.42-3.48 (m, 1H), 4.17 (br, 1H), 5.16 (q, 2H, J=13 Hz), 6.56 (t, 1H, J=7.5 Hz), 6.65 (d, 2H, J=8.0 Hz), 6.70 (d, 1H, J=7.5 Hz), 7.58 (t, 1H, J=8.0 Hz), 7.78 (d, 1H, J=7.5 Hz), 8.20 (d, 1H, J=8.0 Hz), 8.32 (s, 1H); 13 C-NMR (125 MHz, CDCl 3 ): δ 23.18, 26.97, 30.51, 47.31, 69.70, 109.66, 116.28, 122.27, 122.84, 122.99, 123.47, 130.17, 133.92, 135.37, 140.15, 145.15, 148.99; HRMS (ESI): Calcd. for C 17 H 19 N 2 O 3 [M+H] + , 299.1396. found 299.1405. [α] D 18 =+33 (c 0.003, CHCl 3 ), 93% ee; HPLC (AD-H, elute: Hexanes/i-PrOH=99/1, detector: 254 nm, flow rate: 1.0 mL/min), t 1 =14.0 min (minor), t 2 =15.5 min (major).
8-(4-Nitrobenzyloxy)-1,2,3,4-tetrahydro-2-methylquinoline (10b)
1 H-NMR (500 MHz, CDCl 3 ): δ 1.29 (d, 3H, J=6.5 Hz), 1.62-1.69 (m, 1H), 1.96-2.01 (m, 1H), 2.76-2.81 (m, 1H), 2.86-2.93 (m, 1H), 3.43-3.47 (m, 1H), 4.16 (br, 1H), 5.18 (q, 2H, J=13 Hz), 6.55 (t, 1H, J=7.5 Hz), 6.61 (d, 2H, J=7.5 Hz), 6.70 (d, 1H, J=7.5 Hz), 7.60 (d, 2H, J=8.5 Hz), 8.24 (d, 2H, J=8.5 Hz); 13 C-NMR (125 MHz, CDCl 3 ): δ 23.18, 26.95, 30.50, 47.32, 69.60, 109.54, 116.30; 122.29, 122.97, 124.37, 128.27, 135.31, 145.08, 145.44, 148.08; HRMS (ESI): Calcd. for C 17 H 19 N 2 O 3 [M+H] + , 299.1396. found 299.1405. [α] D 18 =+76 (c 0.0032, CHCl 3 ), 90% ee; HPLC (AD-H, elute: Hexanes/i-PrOH=90/10, detector: 254 nm, flow rate: 1.0 mL/min), t 1 =9.5 min (minor), t 2 =11.6 min (major).
8-(4-Methoxybenzyloxy)-1,2,3,4-tetrahydro-2-methylquinoline (11b)
1 H-NMR (500 MHz, CDCl 3 ): δ 1.28 (d, 3H, J=6.0 Hz), 1.64-1.72 (m, 1H), 1.96-2.01 (m, 1H), 2.79-2.84 (m, 1H), 2.89-2.95 (m, 1H), 3.41-3.46 (m, 1H), 3.87 (s, 1H), 4.23 (br, 1H), 5.03 (q, 2H, J=11 Hz), 6.52 (t, 1H, J=8.0 Hz), 6.71 (d, 1H, J=7.5 Hz), 6.75 (d, 1H, J=8.0 Hz), 6.98 (d, 2H, J=9.0 Hz), 7.42 (d, 2H, J=8.5 Hz); 13 C-NMR (125 MHz, CDCl 3 ): δ 23.18, 26.98, 30.65, 47.25, 55.86, 70.71, 109.54, 114.51, 116.25, 121.80, 122.34, 129.99, 130.01, 135.38, 145.88, 160.02; HRMS (ESI): Calcd. for C 18 H 22 NO 2 [M+H] + , 284.1651. found 284.1657. [α] D 18 =+277 (c 0.0033, CHCl 3 ), 92% ee; HPLC (OD-H, elute: Hexanes/i-PrOH=90/10, detector: 254 nm, flow rate: 1.0 mL/min), t 1 =6.6 min (minor), t 2 =9.2 min (major).
8-(3-Methoxybenzyloxy)-1,2,3,4-tetrahydro-2-methylquinoline (12b)
1 H-NMR (500 MHz, CDCl 3 ): δ 1.26 (d, 3H, J=6.5 Hz), 1.61-1.69 (m, 1H), 1.93-1.98 (m, 1H), 2.75-2.80 (m, 1H), 2.85-2.92 (m, 1H), 3.40-3.44 (m, 1H), 3.84 (s, 1H), 4.22 (br, 1H), 5.05 (q, 2H, J=11.5 Hz), 6.56 (t, 1H, J=8.0 Hz), 6.68 (t, 2H, J=8.5 Hz), 6.90 (d, 1H, J=7.5 Hz), 7.03 (t, 2H, J=8.0 Hz), 7.33 (t, 1H, J=8.5 Hz); 13 C-NMR (125 MHz, CDCl 3 ): δ 23.26, 27.03, 30.69, 47.32, 55.90, 70.96, 109.66, 113.71, 114.07, 116.31; 120.47, 121.95, 122.52, 130.24, 135.46, 139.66, 145.83, 160.44; HRMS (ESI): Calcd. for C 18 H 22 NO 2 , 284.1651. found 284.1657 [M+H] + . [α] D 18 =+543 (c 0.0028, CHCl 3 ), 95% ee; HPLC (OD-H, elute: Hexanes/i-PrOH=90/10, detector: 254 nm, flow rate: 1.0 mL/min), t 1 =6.5 min (minor), t 2 =8.1 min (major).
4-((1,2,3,4-Tetrahydro-2-methylquinolin-8-yloxy)methyl)benzonitrile (13b)
1 H-NMR (500 MHz, CDCl 3 ): δ 1.28 (d, 3H, J=6.5 Hz), 1.61-1.69 (m, 1H), 1.96-2.00 (m, 1H), 2.76-2.81 (m, 1H), 2.86-2.92 (m, 1H), 3.42-3.46 (m, 1H), 4.20 (br, 1H), 5.14 (q, 2H, J=13.5 Hz), 6.55 (t, 1H, J=8.0 Hz), 6.61 (d, 2H, J=8.0 Hz), 6.70 (d, 1H, J=7.5 Hz), 7.55 (d, 2H, J=8.0 Hz), 7.68 (d, 2H, J=8.0 Hz); 13 C-NMR (125 MHz, CDCl 3 ): δ 23.16, 26.90, 30.47, 47.25, 69.80, 109.50, 112.15, 116.24, 119.28, 122.17, 122.86, 128.20, 132.92, 135.26, 143.38, 145.09; HRMS (ESI): Calcd. for C 18 H 19 N 2 O [M+H] + , 279.1497. found 279.1510. [α] D 18 =+294 (c 0.0012, CHCl 3 ), 93% ee; HPLC (OD-H, elute: Hexanes/i-PrOH=90/10, detector: 254 nm, flow rate: 1.0 mL/min), t 1 =12.2 min (minor), t 2 =20.5 min (major).
8-(Biphenyl-3-ylmethoxy)-2-methyl-1,2,3,4-tetrahydroquinoline (14b)
1 H-NMR (500 MHz, CDCl 3 ): δ1.30 (d, 3H, J=6.0 Hz), 1.66-1.74 (m, 1H), 1.98-2.03 (m, 1H), 2.81-2.86 (m, 1H), 2.91-2.98 (m, 1H), 3.44-3.50 (m, 1H), 4.30 (br, 1H), 5.18 (q, 2H, J=11.5 Hz), 6.64 (t, 1H, J=8.0 Hz), 6.74 (d, 1H, J=7.5 Hz), 6.79 (d, 1H, J=8.5 Hz), 7.43 (t, 1H, J=8.0 Hz), 7.48-7.55 (m, 4H), 7.64 (d, 1H, J=7.5 Hz), 7.69 (d, 2H, J=7.0 Hz), 7.75 (s, 1H); 13 C-NMR (125 MHz, CDCl 3 ): δ 23.22, 27.02, 30.66, 47.30, 71.12, 109.74, 116.34, 121.94, 122.56, 127.08, 127.21, 127.36, 127.81, 128.06, 129.43, 129.64, 135.46, 138.56, 141.50, 142.12, 145.87; HRMS (ESI): Calcd. for C 23 H 24 NO [M+H] + , 330.1858. found 330.1874. [α] D 18 =+131 (c 0.009, CHCl 3 ), 94% ee; HPLC (OD-H, elute: Hexanes/i-PrOH=90/10, detector: 254 nm, flow rate: 1.0 mL/min), t 1 =7.1 min (minor), t 2 =8.5 min (major).
8-(4-(Trifluoromethoxy)benzyloxy)-1,2,3,4-tetrahydro-2-methylquinoline (15b)
1 H-NMR (500 MHz, CDCl 3 ): δ 1.29 (d, 3H, J=6.0 Hz), 1.64-1.72 (m, 1H), 1.97-2.02 (m, 1H), 2.79-2.84 (m, 1H), 2.89-2.95 (m, 1H), 3.42-3.48 (m, 1H), 4.22 (br, 1H), 5.09 (q, 2H, J=12.0 Hz), 6.60 (t, 1H, J=7.5 Hz), 6.71 (t, 2H, J=8.5 Hz), 7.29 (d, 2H, J=7.5 Hz), 7.50 (d, 2H, J=9.0 Hz); 13 C-NMR (125 MHz, CDCl 3 ): δ 23.19, 27.01, 30.62, 47.35, 70.10, 109.61, 116.34, 121.70, 122.12, 122.17, 122.74, 129.60, 135.41, 136.75, 145.57, 149.49; HRMS (ESI): Calcd. for C 18 H 19 NO 2 F 3 [M+H] + , 338.1368. found 338.1367. [α] D 20 =+30 (c 0.0039, CHCl 3 ), 94% ee; HPLC (OD-H, elute: Hexanes/i-PrOH=90/10, detector: 254 nm, flow rate: 1.0 mL/min), t 1 =5.0 min (minor), t 2 =6.8 min (major)
8-(4-Fluorobenzyloxy)-1,2,3,4-tetrahydro-2-methylquinoline (16b)
1 H-NMR (500 MHz, CDCl 3 ): δ 1.28 (d, 3H, J=6.0 Hz), 1.63-1.71 (m, 1H), 1.96-2.01 (m, 1H), 2.78-2.84 (m, 1H), 2.88-2.95 (m, 1H), 3.41-3.48 (m, 1H), 4.22 (br, 1H), 5.06 (q, 2H, J=11.5 Hz), 6.60 (t, 1H, J=7.5 Hz), 6.71 (d, 2H, J=8.0 Hz), 7.12 (t, 2H, J=8.5 Hz), 7.45 (t, 2H, J=8.0 Hz); 13 C-NMR (125 MHz, CDCl 3 ): δ 23.19, 26.99, 30.62, 47.31, 70.29, 109.57, 116.13, 122.01, 122.59, 130.06, 130.13, 133.72, 133.75, 135.37, 145.66, 162.13, 164.09; HRMS (ESI): Calcd. for C 17 H 19 NOF [M+H] + , 272.1451. found 272.1458. [α] D 18 =+74 (c 0.0042, CHCl 3 ), 94% ee; HPLC (OD-H, elute: Hexanes/i-PrOH=90/10, detector: 254 nm, flow rate: 1.0 mL/min), t 1 =5.4 min (minor), t 2 =7.1 min (major).
8-(4-(Trifluoromethyl)benzyloxy)-1,2,3,4-tetrahydro-2-methylquinoline (17b)
1 H-NMR (500 MHz, CDCl 3 ): δ 1.30 (d, 3H, J=6.0 Hz), 1.64-1.72 (m, 1H), 1.97-2.02 (m, 1H), 2.79-2.84 (m, 1H), 2.88-2.95 (m, 1H), 3.44-3.48 (m, 1H), 4.23 (br, 1H), 5.16 (q, 2H, J=12.5 Hz), 6.59 (t, 1H, J=8.0 Hz), 6.67 (d, 1H, J=8.0 Hz), 6.72 (d, 1H, J=7.5 Hz), 7.58 (d, 2H, J=8.0 Hz), 7.69 (d, 2H, J=8.5 Hz); 13 C-NMR (125 MHz, CDCl 3 ): δ 23.22, 27.02, 30.61, 47.37, 70.11, 109.58, 116.35, 122.20, 122.83, 126.16, 128.14, 130.70, 135.39, 142.11, 145.44; HRMS (ESI): Calcd. for C 18 H 19 NOF 3 [M+H] + , 322.1419. found 322.1417. [α] D 18 =+60 (c 0.002, CHCl 3 ), 95% ee; HPLC (OD-H, elute: Hexanes/i-PrOH=90/10, detector: 254 nm, flow rate: 1.0 mL/min), t 1 =5.4 min (minor), t 2 =7.7 min (major).
8-(4-Chlorobenzyloxy)-1,2,3,4-tetrahydro-2-methylquinoline (18b)
1 H-NMR (500 MHz, CDCl 3 ): δ 1.27 (d, 3H, J=6.5 Hz), 1.61-1.69 (m, 1H), 1.94-1.99 (m, 1H), 2.76-2.81 (m, 1H), 2.86-2.93 (m, 1H), 3.39-3.46 (m, 1H), 4.18 (br, 1H), 5.04 (q, 2H, J=12.0 Hz), 6.57 (t, 1H, J=7.5 Hz), 6.68 (dd, 2H, J=8.0 Hz), 7.39 (s, 4H); 13 C-NMR (125 MHz, CDCl 3 ): δ 23.24, 27.01, 30.63, 47.33, 70.21, 109.58, 116.31, 122.07, 122.66, 129.36, 129.58, 134.34, 135.39, 136.50, 145.57; HRMS (ESI): Calcd. for C 17 H 19 NOCl [M+H] + , 288.1155. found 288.1161. [α] D 18 =+254 (c 0.0024, CHCl 3 ), 95% ee; HPLC (OD-H, elute: Hexanes/i-PrOH=90/10, detector: 254 nm, flow rate: 1.0 mL/min), t 1 =5.5 min (minor), (t 2 =7.4 min (major).
8-(Benzyloxy)-1,2,3,4-tetrahydro-2-phenethylquinoline (28b)
1 H-NMR (500 MHz, CDCl 3 ): δ 1.74-1.78 (m, 1H), 1.79-1.97 (m, 2H), 2.06-2.11 (m, 1H), 2.78-2.94 (m, 4H), 3.33-3.38 (m, 1H), 4.41 (ds, 1H), 5.13 (q, 2H, J=6.0 Hz), 6.62 (t, 1H, J=8.0 Hz), 6.74 (dd, 2H, J=8.0 Hz), 7.23-7.27 (m, 3H), 7.34 (t, 2H, J=7.5 Hz), 7.39 (t, 1H, J=7.0 Hz), 7.46 (t, 2H, J=7.0 Hz), 7.51 (d, 2H, J=7.0 Hz); 13 C-NMR (125 MHz, CDCl 3 ): δ 26.59, 28.43, 32.77, 38.79, 51.05, 71.06, 109.80, 116.32, 122.05, 122.48, 126.54, 128.13, 128.54, 129.01, 129.08, 129.20, 135.25, 138.10, 142.52, 145.93; HRMS (ESI): Calcd. for C 24 H 26 NO [M+H] + , 344.2014. found 344.2029. HPLC (OD-H, elute: Hexanes/i-PrOH=90/10, detector: 254 nm, flow rate: 1.0 mL/min), t 1 =8.15 min, t 2 =11.38 min.
2-(3,4-Dimethoxyphenethyl)-1,2,3,4-tetrahydroquinoline (31b)
1 H-NMR (500 MHz, CDCl 3 ): δ 1.67-1.75 (m, 1H), 1.82-1.87 (m, 2H), 2.00-2.05 (m, 1H), 2.71-2.79 (m, 2H), 2.80-2.88 (m, 2H), 3.31-3.36 (m, 1H), 3.90 (d, 6H, J=8.0 Hz), 6.48 (d, 1H, J=7.5 Hz), 6.64 (t, 1H, J=7.5 Hz), 6.78 (d, 2H, J=8.5 Hz), 6.84 (d, 1H, J=8.5 Hz), 6.99 (t, 2H, J=7.0 Hz); 13 C-NMR (125 MHz, CDCl 3 ): δ 26.79, 28.59, 32.40, 38.99, 51.79, 56.44, 56.54, 111.97, 112.28, 114.72, 117.59, 120.73, 121.84, 127.31, 129.82, 135.08, 145.11, 147.91, 149.56; HRMS (ESI): Calcd. for C 19 H 24 NO 2 [M+H] + , 298.1807. found 298.1808.
5,7-dibromo-2-methyl-8-(4-(trifluoromethyl)benzyloxy)-1,2,3,4-tetrahydroquinoline (32b)
1 H-NMR (500 MHz, CDCl 3 ): δ 1.13 (d, 3H, J=6.0 Hz), 1.46-1.54 (m, 1H), 1.93-1.97 (m, 1H), 2.57-2.64 (m, 1H), 2.78-2.83 (m, 1H), 3.22-3.26 (m, 1H), 4.20 (bs, 1H), 4.98 (q, 2H, J=11 Hz), 7.06 (s, 1H), 7.61 (d, 2H, J=8.0 Hz), 7.67 (d, 2H, J=8.5 Hz); 13 C-NMR (125 MHz, CDCl 3 ): δ 22.62, 27.91, 29.94, 46.80, 73.62, 114.77, 121.42, 121.49, 122.64, 126.17, 126.20, 126.23, 126.26, 128.97, 131.07, 141.19, 141.51, 141.55; HRMS (ESI): Calcd. for C 18 H 17 NOF 3 Br 2 [M+H] + , 477.9629. found 477.9651. HPLC (OD-H, elute: Hexanes/i-PrOH=90/10, detector: 254 nm, flow rate: 1.0 mL/min), (S) t 1 =3.99 min, (R) t 2 =4.89 min.
5,7-dibromo-2-methyl-8-(4-(trifluoromethoxy)benzyloxy)-1,2,3,4-tetrahydroquinoline (33b)
1 H-NMR (500 MHz, CDCl 3 ): δ 1.13 (d, 3H, J=6.0 Hz), 1.45-1.53 (m, 1H), 1.92-1.96 (m, 1H), 2.56-2.63 (m, 1H), 2.78-2.83 (m, 1H), 3.19-3.24 (m, 1H), 4.20 (bs, 1H), 4.92 (q, 2H, J=11 Hz), 7.05 (s, 1H), 7.26 (d, 2H, J=8.0 Hz), 7.52 (d, 2H, J=8.5 Hz); 13 C-NMR (125 MHz, CDCl 3 ): δ 22.58, 27.92, 29.95, 46.77, 73.69, 114.80, 120.10, 121.32, 121.39, 121.78, 122.15, 122.58, 130.56, 136.28, 141.19, 141.61, 149.91; HRMS (ESI): Calcd. for C 18 H 17 NO 2 F 3 Br 2 [M+H] + , 493.9578. found 493.9572. HPLC (OD-H, elute: Hexanes/i-PrOH=90/10, detector: 254 nm, flow rate: 1.0 mL/min), (S) t 1 =3.83 min, (R) t 2 =4.54 min.
Synthesis of Quinoline Dimer
A mixture of 2-methylquinolin-8-ol (2.4 g, 15 mmol) and dihaloalkyl (5 mmol) in ACN was added K 2 CO 3 (2.28 g, 16.5 mmol) and refluxed overnight. Then the ACN was removed and hydrolysed with water. The organic product was extracted with EA (3×50 mL). The combined organic layers were dried over anhydrous sodium sulfate. The solvent was removed under reduced pressure and the crude product was purified by silica gel column chromatography to give the pure product.
1,6-bis(2-methylquinolin-8-yloxy)hexane (34a)
1 H-NMR (500 MHz, CDCl 3 ): δ 1.52-1.55 (m, 4H), 1.94-1.97 (m, 4H), 2.64 (s, 6H), 4.13 (t, 4H, J=7.0 Hz), 6.90 (d, 2H, J=7.5 Hz), 7.14 (d, 2H, J=8.5 Hz), 7.18 (d, 2H, J=8.0 Hz), 7.23 (t, 2H, J=8.0 Hz), 7.84 (d, 2H, J=8.5 Hz); 13 C-NMR (100 MHz, CDCl 3 ): δ 26.29, 26.51, 29.44, 69.52, 109.66, 119.88, 122.96, 126.22, 128.26, 136.56, 140.53, 154.89, 158.55; Yield=41.8%.
Synthesis of Soluble Salts of Quinoline Compounds
To a stirred solution of quinolines or tetrahydroquinolines (0.57 mmol) in dichloromethane (20 ml), hydrochloride gas was bubbled at room temperature. The precipitate was collected by filtration to give the designed product.
1 H-NMR (500 MHz, DMSO): δ 3.73 (s, 1H), 7.27 (d, 1H, J=7.5 Hz), 7.55 (d, 1H, J=8.5 Hz), 7.66 (t, 1H, J=8.0 Hz), 8.00 (d, 1H, J=8.5 Hz), 8.55 (d, 1H, J=8.0 Hz), 10.19 (s, 1H); 13 C-NMR (125 MHz, DMSO): δ 113.49, 117.89, 118.55, 131.33, 131.46, 138.40, 138.91, 151.03, 155.15, 194.13; yield=96.5%; Melting point: 185° C.
1 H NMR (500 MHz, DMSO): δ 1.46 (d, 3H, J=6.5), 1.78-1.86 (m, 1H), 2.03-2.06 (m, 1H), 2.78-2.90 (m, 2H), 3.41-3.46 (m, 1H), 6.73 (d, 1H, J=7.5), 7.00 (d, 1H, J=8.0), 7.16 (t, 1H, J=8.0), 10.59 (s, 1H), 11.06 (s, 1H); 13 C-NMR (125 MHz, DMSO): δ 18.97, 25.92, 27.43, 51.52, 114.45, 120.11, 120.94, 129.60, 133.43, 152.07; yield=92.8%; Melting point: 252.6° C.
1 H NMR (500 MHz, DMSO): δ 1.34 (d, 3H, J=5.0), 1.63-1.71 (m, 1H), 1.98-2.03 (m, 1H), 2.59-2.66 (m, 1H), 2.69-2.74 (m, 1H), 3.37-3.41 (m, 1H), 6.42 (bs, 4H), 7.41 (s, 1H); 13 C-NMR (125 MHz, DMSO): δ 20.52, 27.93, 28.30, 49.23, 110.22, 115.93, 126.81, 128.86, 131.33, 145.05.
Lung carcinoma cell line (A549) and hepatocellular carcinoma (HCC) cell line (Hep3B) were obtained from American Type of Culture Collection (ATCC). Esophageal squamous cell carcinoma cell line KYSE150 was purchased from DSMZ (Braunschweig, Germany) [13]. Esophageal squamous cell carcinoma (ESCC) cell line HKESC1 was kindly provided by Professor Gopesh Srivastava of the Department of Pathology, The University of Hong Kong [14]. ESCC cell line HKESC-4 was kindly provided by Professor Simon Law of the Department of Surgery, The University of Hong Kong [15]. Hep3B HCC and A549 lung carcinoma cell lines were maintained in DMEM and F12-K medium respectively with 10% of heat inactivated fetal bovine serum (Hyclone) together with antibiotics involving penicillin and streptomycin. All the ESCC cell lines (KYSE150, HKESC-1 and HKESC-4) were maintained in MEM supplemented with 10% of heat inactivated fetal bovine serum together with antibiotics involving penicillin and streptomycin. Cells were allowed to grow in a humidified cell culture incubator keeping at 5% carbon dioxide.
In Vitro Cytotoxicity Against Cancer Cell Lines
Human liver cancer cell line Hep3B was used for purpose of preliminary anti-cancer screening for the selected alkaloids. Cancer cells (1×10 4 per well) seeded in the 96 wells microtitre plates for 24 hours were prepared for the alkaloid screening. The selected compounds were prepared as a stock concentration of 50 mg/ml in dimethylsulfoxide (DMSO) and were added at a concentration of 50 μg/ml and incubated for a further of 48 hours. Untreated control received either total complete medium or 0.1% of DMSO. Cisplatin (CDDP, also at 50 μg/ml) was the positive reference which induced more than 95% in Hep3B. Afterwards, the evaluation of possible antiproliferative or cytotoxicity of those alkaloids was examined by the One Step ATP lite assay purchased from PerkinElmer according to the technical manual provided. Table 1 showed some preliminary results on antitumor activities. The relative MTS activities were compared with the untreated control and illustrated using symbols “+” (more cell death) and “−” (no cytotoxicity).
TABLE 1 Relative anticancer activity among quinoline compounds (50 ug/ml) Compound Formula B R 1 R 2 R 3 R 4 R 5 R 6 R 7 R 8 Relative activity to untreated control 11a H H H H CH 3 H H +++ 12a H H H H CH 3 H H +++++ 14a H H H H CH 3 H H +++++ 15a H H H H CH 3 H H +++ 17a H H H H CH 3 H H +++ 19a H H H H CH 3 H H — 23a H H H OBn H OBn H H +++ 27a H H H OBn H CH 2 CH 3 H H +++++ 28a H H H OBn H CH 2 CH 2 Ph H H ++++ Compound Formula A R 1 R 2 R 3 R 4 R 5 R 6 R 7 R 8 Relative activity to untreated control 2b Br H Br OH H CH 3 H H +++++ 5b H H H OH H CH 2 OH H H +++++ 8b H H H H CH 3 H H + 9b H H H H CH 3 H H — 10b H H H H CH 3 H H — 11b H H H H CH 3 H H — 12b H H H H CH 3 H H — 13b H H H H CH 3 H H ++++ 14b H H H H CH 3 H H — 15b H H H H CH 3 H H +++ 16b H H H H CH 3 H H ++ 17b H H H H CH 3 H H +++++ 18b H H H H CH 3 H H +++ 25b H H H OAc H CH 3 H H + 26b H H H OAc Ac CH 3 H H + 28a H H H OBn H CH 2 CH 2 Ph H H ++++ 24a +++++
In Table 1, Formulas A and B are more clearly shown as follows.
MTS ([3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophen-yl)-H-tetrazolium]) Assay
Changes in the cellular viability of compound 11-17a, 9-18b and enantioselective (+)-2b and (−)-2b treated cells were monitored using the MTS activity assay which is known and was reported previously (see reference number 16 below). Results were tabulated in Table 2 and Table 3. Briefly, 1×10 4 carcinoma cells were seeded at day 0. After 24 hours, medium was changed and various compounds were added at different concentrations. Cisplatin (CDDP), a commonly used anti-cancer agent, was also used as the positive control. After 48 hours of incubation, the medium was removed and MTS/PMS solution was added and they were incubated further for exactly 30 minutes. Afterwards, optical absorbance was determined at 490 nm according to the user manual (Promega). All the assays were done in triplicates.
TABLE 2 Relative anticancer activity among quinoline compounds Relative MTS Activity at 50 μg/mL Concentration Comp'd Hep3B A549 HKESC-1 HKESC-4 HKESC150 11a 0.320 ± 0.017 0.527 ± 0.018 0.817 ± 0.076 0.488 ± 0.017 0.797 ± 0.083 12a 0.209 ± 0.030 n.d. 0.535 ± 0.032 0.794 ± 0.005 0.648 ± 0.013 14a 0.370 ± 0.214 0.244 ± 0.003 n.d. n.d. n.d. 15a 0.777 ± 0.130 0.629 ± 0.081 n.d. n.d. n.d. 17a 0.878 ± 0.073 0.920 ± 0.042 n.d. n.d. n.d. 9b 0.688 ± 0.027 0.706 ± 0.184 0.453 ± 0.012 0.698 ± 0.096 0.619 ± 0.025 10b 1.264 ± 0.030 1.659 ± 0.173 1.337 ± 0.145 1.056 ± 0.050 1.097 ± 0.036 11b 0.554 ± 0.114 0.759 ± 0.079 0.917 ± 0.023 0.777 ± 0.019 0.764 ± 0.001 12b 0.726 ± 0.065 n.d. 0.682 ± 0.001 0.716 ± 0.022 0.845 ± 0.010 13b 0.842 ± 0.024 n.d. 0.754 ± 0.017 0.424 ± 0.062 0.470 ± 0.087 14b 0.510 ± 0.068 1.238 ± 0.066 n.d. n.d. n.d. 15b 0.760 ± 0.090 0.840 ± 0.029 n.d. n.d. n.d. 16b 0.412 ± 0.017 0.908 ± 0.063 n.d. n.d. n.d. 17b 0.734 ± 0.024 0.983 ± 0.001 n.d. n.d. n.d. 18b 0.609 ± 0.042 1.089 ± 0.039 n.d. n.d. n.d. CDDP 0.116 ± 0.031 0.216 ± 0.075 0.135 ± 0.017 0.158 ± 0.081 0.205 ± 0.032
In Vitro Studies of (+)-2b and (−)-2b
We screened (+)-2b and (−)-2b for their effects on cell proliferation and potential cytotoxicity in different cell lines. As shown in FIG. 1 , both (+)-2b and (−)-2b showed considerable suppressing effects on cancer cell growth with MTS 50 ranging from 4 to 10 μg/mL.
In the present invention, studies of cytotoxic activity of (+)-2b and (−)-2b (example 11) were carried out on the five carcinoma cell lines (Hep3B, A549, HKESC-1, HKESC-4 and KYSE150) by means of MTS assay. In vitro studies, the (+)-2b showed similar MTS 50 activity (50% of MTS reduction ability by the chemical treated cell as compared with control) to (−)-2b against the cancer cell lines (MTS 50 =˜5 μg/mL). Our preliminary results showed that the (+)-2b exhibited a more than 2-fold cytotoxic activity to the cell line KYSE150 than CDDP, and (+)-2b also exhibited a 1.5-fold cytotoxic activity to the cell lines Hep3B, HKESC-1 and HKESC-4 than CDDP. (+)-2b and (−)-2b showed similar cytotoxic effects on Hep3B, HKESC-4 and A549. These interesting results prompt us to further investigate the underlying molecular mechanisms of antiproliferation.
In Vivo Anti-Cancer Effects of (−)-2b
Optically pure compound (−)-2b (ee up 99%) was tested for their anti-cancer effects against the subcutaneous xenograft tumors of human esophageal cancer derived from the cell line KYSE150, which was purchased from DSMZ (Braunschweig, Germany) and was cultured in a known way as previously described (for details see reference number 17).
Each group of three mice received intra-peritoneal (i.p.) injection daily with 10 mg/kg of optically pure isomers with 6% polyethylene glycol (PEG Mn 8000) for 19 days. The control group of two mice was injected daily with 6% PEG only. Tumor dimensions were measured regularly with calipers, and tumor volumes were estimated using two-dimensional measurements of length and width and calculated with the formula [l×(w) 2 ]×0.52 (l is length and w is width) as previously described. As shown in FIG. 2 , the overall results demonstrated that the compound (−)-2b (10 mg/kg/day) is effective in suppressing the volume growth of the KYSE150 xenograft tumors in nude mice compared with the negative control.
Histological examination of liver, heart, lung and kidney sections of the mice after sacrifice showed no observable damage.
While there have been described and pointed out fundamental novel features of the invention as applied to a preferred embodiment thereof, it will be understood that various omissions and substitutions and changes, in the form and details of the embodiments illustrated, may be made by those skilled in the art without departing from the spirit of the invention. The invention is not limited by the embodiments described above which are presented as examples only but can be modified in various ways within the scope of protection defined by the appended patent claims.
REFERENCES
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2. Somberg J C., Ranade V. ‘Optically active isomers of quinine and quinidine and their respective biological action.’ 2001 (Int. patent no. WO/2001/046188)
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12. Chan, A S C.; Tang, J C O.; Lam, K H.; Chui, C H.; Kok, S H L.; Chan, S H; Cheung, F; Gambari, R.; Cheng, C H ‘Method of Making and Administering Quinoline Derivatives as Anti-Cancer Agents.’ 2009 (Int. patent no. WO2009024095A1)
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16. (a) Chui, C H.; Cheng, G Y.; Ke, B.; Lau, F Y.; Wong, R S.; Kok, S H.; Fatima, S.; Cheung, F.; Cheng, C H.; Chan, A S C. Tang, J C O. Int. J. Mol. Med. 2004, 14, 975-979; (b) Kok, S H L.; Chui, H C.; Lam, W S.; Chen, J.; Lau, F Y.; Wong, R S. M.; Cheng, G Y M.; Tang, W K.; Cheng, C H.; Tang, J C O.; Chan, A S C. Int. J. Mol. Med. 2006, 18, 375-379; (c) Kok, S H L.; Gambari, R.; Chui, H C.; Lam, W S.; Chen, J.; Lau, F Y.; Wong, R S M.; Cheng, G Y M.; Lai, P B S.; Leung, T W T.; Chan, A S C.; Tang, J C O. Minerva Biotecnologica, 2006, 18, 153-157; (d) Kok, S H L.; Chui, H C.; Lam, W S.; Chen, J.; Lau, F Y.; Wong, R S M.; Cheng, G Y M.; Tang, W K.; Teo, I T N.; Cheung, F.; Cheng, C H.; Chan, A S C.; Tang, J C O. Int. J. Mol. Med. 2006, 18, 1217-1221; (e) Kok, S H L.; Chui, H C.; Lam, W S.; Chen, J.; Lau, F Y.; Wong, R S M.; Cheng, G Y M.; Lai, P B S.; Leung, T W T.; Tang, J C O.; Chan, A S C. Bioorg. Med. Chem. Lett. 2007, 17, 1155-1159.
17. Shimada Y., Imamura M., Wagata T., Yamaguchi N. and Tobe T. Cancer 1992, 69, 277-284.
18. Guba M., von Breitenbuch P., Steinbauer M., Koehl G., Flegel S., Hornung M., Bruns C J., Zuelke C., Farkas S., Anthuber M., Jauch K W., Geissler E K. Nature Medicine 2002, 8, 128-35.
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Quinoline derivatives showing anticancer activities against cancer cell lines of hepatocellular carcinoma (Hep3B), lung carcinoma (A549), esophageal squamous cell carcinoma (HKESC-1, HKESC-4 and KYSE150). The quinoline derivatives have a backbone structure of the following formulas:
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FIELD OF THE INVENTION
This invention relates to improvements to internal combustion engines. The invention particularly relates to an engine configuration in which the rate of compression and expansion of the combustion chamber may be readily modified.
BACKGROUND
The most common type of existing internal combustion engines include pistons connected via conrods to a crankshaft, whereby the pistons reciprocate cyclically within respective cylinders to perform the functions of induction, compression, expansion and exhaust of the working fluid.
Work is extracted from the working fluid by the combustion process wherein the expanding combusted gases resulting from combustion of the compressed working fluid forces the piston through the cylinder forcing rotation of the crankshaft.
The rotating mass of the crankshaft enables energy to be stored. The stored energy is applied to enable the piston to perform work on the working fluid in order to compress it prior to the combustion process. The work performed during compression, which is hereinafter referred to as “negative” work, reduces the total work which can be extracted via the engine's crankshaft.
This “negative” work is significantly increased if the combustion process commences during the compression process. In addition, any heat loss from the products of combustion of the working fluid are energy losses which cannot be converted into useful work extractable from the crankshaft.
In conventional engines the rate of change of the combustion chamber's volume during compression and expansion varies identically and sinusoidally. That is, the time-volume function of the combustion chamber, which is directly related to the time-displacement function of the piston, is sinusoidal. In particular, the piston has greatest velocity during the middle of each stroke and instantaneously zero velocity at the top and bottom of each stroke.
However, in the combustion process pressure increases rapidly due to the rapid production of combustion gases. The combustion gases then behave substantially in accordance with the gas laws. The result in conventional engines is a non-adiabatic expansion of the combustion gases as the initial slow movement of the piston and thus expansion of the working chamber prevents initial fast expansion of the working fluid.
The slow initial movement of the piston results in significant pressure and temperature increases which are believed to cause consequent massive heat losses through the walls of the working chamber. Accordingly the efficiency of the conventional petrol engine in converting chemical energy released by combustion into useable mechanical energy is only about 25%.
In effect, the conventional crankshaft driven piston is systematically misplaced throughout its cycle in relation to the behaviour of the products of combustion. While it is possible to vary, for example, the stroke length of the sinusoidal motion of the piston in the engine cylinder of a conventional engine, no modification will alter time-displacement function of the piston, and hence the time-volume function of the combustion chamber, from being sinusoidal in form. Accordingly it is not possible to readily alter a conventional engine so that the time-displacement function is not sinusoidal but is of some other form which may provide for greater engine efficiency.
Furthermore, while the crankshaft mechanism for internal combustion engines has many desirable features, such as simplicity, strength and reliability, it has mechanical disadvantages such as being unbalanced resulting in vibration.
The present invention aims to provide an internal combustion engine which is configured to allow the time-displacement function of the combustion chamber to be changed by a straightforward modification.
SUMMARY OF THE INVENTION
According to a first aspect of the invention there is provided an internal combustion engine including:
at least three radial cylinders disposed with their axes coplanar and equi-angularly disposed about a point common to each axis, the cylinders meeting to form a common combustion chamber;
a piston located in each of said radial cylinders, each piston cooperating with a cam profile formed by the inner wall of a rotor,
the cam profile being rotationally symmetrical and including the same number of lobes as pistons, each lobe projecting radially inwards, the lobes equi-angularly disposed about the inner wall.
In operation, the pistons may mutually expand/compress the combustion chamber in accordance with other than a sinusoidal time-displacement function.
Preferably the engine includes an output shaft collinear with the engine axis drivingly connected to the rotor.
Alternatively the rotor may be fixed with the cylinders and pistons rotatable, in that case the output shaft may be drivingly connected, to the cylinders.
As a further alternative the rotor may be rotatable and have an armature winding for inclusion as part of an electric generator.
The engine may include poppet valves to regulate the introduction and exhaust of fluids from the cylinders.
The engine may be provided with a number of interchangeable rotors having differently shaped lobes.
The engine may be incorporated into a vehicle.
Preferably the engine includes ignition timing means arranged to operatively cause ignition to commence upon the pistons being cammed to a top-dead centre position at which the common combustion chamber is minimised.
It is preferred that each lobe be shaped with an innermost extent defining a camming surface of constant radial distance from the first axis thereby causing each piston to maintain a top dead centre position for a non-zero period of time.
The engine may be operated as a ported two stroke engine with low profile ports at the bottom of the cylinder such that the effective stroke of the piston compared to a conventional two stroke engine is substantially increased. Due to the circular configuration of the rotor there is a cessation of piston while between camming by the lobes so that maximum expansion of the combustion chamber may be prolonged. By prolonging the maximum expansion of the combustion chamber, effective scavenging of the exhaust gases from the cylinder, before the next compression stroke commences, is possible.
In an engine of the type described the cam profile may be changed by reshaping the lobes, or replacing the rotor with another rotor having a varied lobe shape, until a cam profile which maximises engine efficiency for a particular engine configuration, operational speed or fuel type is found.
Altering the shape of the lobes may be achieved by filing or otherwise machining or shaping the lobes.
The expansion and compression strokes need not be mirror images of one another. Unlike a conventional crank-shaft engine, the piston speed need not peak at mid-stroke and there can be a multitude of acceleration patterns depending upon the shape of the lobes. The cam profile may be chosen to maximise efficiency for a particular class of engine depending on the scale of the engine, the fuel burned, the compression ratio chosen and the thermal properties of the materials used for building the engine.
As the engine uses radially disposed cylinders sharing a common combustion chamber and is arranged with the cylinders and pistons being rotationally symmetrical, the design is balanced so that vibration is minimised.
If the engine is to be operated in a four stroke mode then it is not essential that all the lobes be of identical shape. For example, in a four stroke engine having four cylinders the lobes camming the pistons during the exhaust and intake strokes may be of similar or identical shape whereas the lobes for camming the pistons during the compression and power strokes may be of another shape.
Operation in a four stroke mode entails the inclusion of valves and valve opening means arranged to facilitate introduction and exhaust of working fluids into and out of the combustion chamber and also to close the combustion chamber during the compression and power strokes.
According to a further aspect of the invention there is provided a method for maximising the efficiency of an engine of the type described above, the method including the steps of:
measuring the efficiency of the engine;
modifying the shape of the lobes;
repeating the steps of measuring and modifying until a desired level of efficiency is obtained.
BRIEF DESCRIPTION OF THE FIGURES
In order that this invention may be more readily understood and put into practical effect, reference will now be made to the accompanying drawings which illustrate a preferred embodiment and wherein:
FIG. 1 diagrammatically illustrates an engine according to an embodiment of the present invention in front view with the pistons disposed at maximum cylinder chamber volume.
FIG. 1A is a side view of the engine of FIG. 1 .
FIG. 2 is a front view of the engine of FIG. 1 with the pistons disposed at a position for minimum cylinder chamber volume.
FIG. 2A is a side view of the engine of FIG. 2 .
FIG. 3 is a time/displacement graph of a conventional two-stroke crank engine.
FIG. 4 is a time displacement graph of the engine of FIG. 1 .
FIG. 5 is an illustration of the relative displacements of the four pistons of the engine of FIG. 1 .
FIG. 6 illustrates a further embodiment of an engine according to the present invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Referring now to FIGS. 1 and 2 , the inner structure of an engine according to an embodiment of the present invention is depicted. Engine 10 has an outer housing 11 provided with an annular side wall 12 which surrounds a rotor assembly 13 mounted rotatably in housing 11 on an output shaft 14 .
The housing 11 has a front wall 15 which supports a branched cylinder assembly 16 having four cylinders 17 disposed in a common plane and equi-angularly disposed at 90 degrees to each other. Each cylinder 17 opens to a common combustion chamber 18 .
Respective pistons 20 are slidably arranged in each cylinder 17 and each is interconnected by a respective conrod 21 to a roller assembly 22 having its rolling surface in contact with an internal cam profile 23 formed on the inside of the rotor assembly 13 . It will be seen that the cam profile 23 has four base segments 24 spaced equally along the periphery of the profile 23 and four equally spaced peak segments 26 or “lobes”.
It will be understood that the term “lobe” when used herein in both the description and the claims is intended to refer to profile segments for bringing the pistons to a position where the combustion chamber is minimised.
The base and peak segments extend at a constant radius whereby the roller assemblies 22 may move without displacing the pistons 20 in the cylinders 17 .
The constant radius base segment 24 and peak segments 26 are interconnected by ramp segments including leading ramp segments 25 which, upon clockwise rotation of the rotor assembly 13 , simultaneously force the pistons to move from their maximum expansion positions, (bottom dead centre) illustrated in FIG. 1 to their maximum compression positions (top dead centre) illustrated in FIG. 2 . Roller assemblies 22 subsequently cam over trailing ramps 27 as the pistons 20 return to maximum expansion positions under the influence of gas pressure in the combustion chamber 18 .
Although not illustrated, an inlet is provided to the combustion chamber for admission of the air/fuel mixture or air if direct fuel injection is utilised and a spark plug if the engine is adapted as a spark ignition engine. The fuel/air mixture may be introduced in any known and suitable manner. Suitably the engine operates as a two-stroke and a low profile exhaust port 28 is provided at the base of each cylinder. A spark plug is suitably positioned in the cylinder wall substantially concentric with the drive shaft axis and an inlet port or ports may be piston controlled or valve controlled as desired.
In the illustrated embodiment, each conrod 21 is forked to support the roller axle 30 at opposite sides of the roller 29 and to enable the roller axle 30 to extend outwardly beyond the conrod for engagement in linear slots 31 which maintain the axis of the roller in alignment with the axis of the respective cylinder 17 .
Suitably the conrods 21 are connected to the pistons 20 via a pin connection at right angles to the axles 30 such that in effect, the conrod provides a universal connection between each roller assembly 22 and the respective piston with a view to minimising any piston side loads which may result in use from slight misalignment of the moving parts. It will be seen that as the cam profile 23 on the rotor assembly 13 moves relative to the rollers 22 each roller 22 is simultaneously contacted by a leading ramp segment 25 forcing the pistons inwardly to maximum compression positions at which they are held by the peak segments 26 during further rotation of the rotor until the rollers 22 travel there across to the trailing segments 27 allowing the pistons 20 to move back to maximum expansion positions at which they rest while the rollers 22 move along the base segments 24 prior to contacting the next leading ramp segment 25 when the cycle is repeated.
From the above it will be seen that the cam profile 23 may be configured to achieve variations in the time-displacement function followed by a piston during each cycle. Consequently the combustion chamber may expand and compress in accordance with other than a sinusoidal time-displacement function as is the case in conventional crank shaft driven engines. Furthermore the cam profile may be configured to enable the engine 10 to realise a desired time-displacement function in order that the piston's motions conform to a selected energy management program.
A graph of a time-displacement function for a two stroke crank shaft-driven engine appears in FIG. 2 . It will be seen that ignition occurs while the piston is on the up stroke thus causing the piston to work against the products of combustion. Furthermore, peak combustion pressure is achieved after partial expansion of the working chamber has commenced thus reducing the power which may be extracted from the engine and that the exhaust port opens at the point marked ‘blow down’ well before the piston has reached its bottom dead centre position. The timing of events in the graph of FIG. 2 is necessary to allow sufficient open duration for the exhaust gases to escape or be extracted so that they do not significantly contaminate the fresh incoming charge.
By comparison FIG. 4 is a graph of a preferred time-displacement function for an engine according to the present invention. It will be seen that compression occurs rapidly during a relatively small rotation of the rotor/output shaft and that ignition occurs while the combustion gases are held at a constant volume and that the low profile port enables a much fuller working expansion of the products of combustion. This is possible as the low profile port remains open for a longer period while the rollers travel along the respective base segments of the cam profile.
Furthermore as the pistons move in unison and in opposite directions while performing their same functions and shared gas is bearing on all of the pistons at any time throughout the cycle, the pressure on each piston at any instant will be the same. Thus the engine should operate with less harsh vibrations than comparable conventional engine.
In a preferred embodiment of the invention the engine fires (n) times per revolution. The forces on individual components is low because it is shared. If there are four pistons, they will deliver four impulses to the rotor at every firing, and as there are four firings per revolution, there are sixteen impulses per revolution from a single chamber.
Each engine has a characteristic number which equals:
the number of lobes of the rotor cam profile; the number of branches in cylinders; the number of pistons and roller assemblies, and the number of firings per revolution.
The choice of this characteristic number will depend on the designer's purposes. However it is considered that as this characteristic number increases so too does the number of parts, the operating torque, while the RPM, the length of the stroke, the piston speed, the engine diameter and the loads on individual components decreases along with wear factors.
The engine 40 illustrated in FIG. 6 shows the rollers 42 guided in sliders 43 for movement to and from the cylinders 44 . The sliders 43 could form pistons sliding in guide cylinders 45 so as to be capable of developing pumping chambers for charging the cylinders 44 such as in the manner of conventional crankcase compression or otherwise as desired.
Alternatively an external supply of pressurised air or air/fuel mix, or a further similar engine bank or supercharger or turbocharger may be used for charging the working cylinders.
It will be seen that an engine according to this invention can be configured so that the chamber volume at any given time is optimised to regulate the energy released through combustion, the energy captured through resisted expansion and energy lost through heat transfer into the chamber walls. Thus temperature of the working fluid may be raised to its desired level as quickly as practicable, and then expanded quickly before too much thermal energy dissipates into the walls of the working chamber.
It will also be seen that the location and the velocity of the pistons is not, for design purposes, fixed to the output shaft rotation angle, making these parameters adjustable. Consequently it is possible to shape the cam profile in working fluid may be raised to its desired level as quickly as practicable, and then expanded quickly before too much thermal energy dissipates into the walls of the working chamber.
It will also be seen that the location and the velocity of the pistons is not, for design purposes, fixed to the output shaft rotation angle, making these parameters adjustable. Consequently it is possible to shape the cam profile in order to realise piston time-displacement functions which result in variations in combustion chamber tailored to create the preferred combination of process variables at any stage in the cycle. Temperature and pressure are functions of volume, so by controlling volume change it is possible to manage the conditions inside the combustion chamber.
Thus it is believed that the processes of thermal energy release, thermal energy escape and thermal energy capture can be co-ordinated, so as to give preferred patterns of emission and fuel efficiency.
For example, an engine according to an embodiment of the invention may be tested for fuel efficiency, the lobe shapes may then be modified, for example by filing in order to alter the time-displacement function followed by the piston until a desired fuel efficiency or other operating parameter is obtained.
The use of multiple pistons pushing and being pushed by a common volume of gas permits faster expansion rates with slower piston speeds. It also allows high expansion ratios with shorter individual piston strokes.
The radially symmetrical design allows radial opposition of both reciprocating and rotating parts, so there is no need for counterweights. In addition because of the concentric design and the simultaneous action of opposed pistons, the preferred engine is balanced, so heavy casting and counterweights are unnecessary. This leads to saving in engine weight. However designs other than concentric layouts may be utilised if desired such as conventional in-line arrangements with cams operating the pistons.
It will of course be realised that the above has been given only by way of illustrative example of the invention. Although in the embodiment depicted there are four cylinders other configurations are possible. For example a three cylinder variant may be constructed with the cylinders disposed at 120 degrees to each other. Furthermore, rather than extract mechanical energy from the engine the rotor could have an armature winding around it and form part of an electrical generator in which case power would be available in electrical form.
While the engine described in the embodiment of FIGS. 1 and 2 is intended for operation in a two-stroke mode, other embodiments may be configured to operated in dedicated four stroke mode.
If the engine is to be operated in a four stroke mode then it is not essential that all the lobes be of identical shape. For example, in a four stroke engine having four cylinders the lobes camming the pistons during the exhaust and intake strokes may be of similar or identical shape whereas the lobes for camming the pistons during the compression and power strokes may be of another shape.
It will be understood that an engine in accordance with an embodiment of the present invention may find application as a power unit for a vehicle.
All other modifications and variations thereto as would be apparent to persons skilled in the art are deemed to fall within the broad scope and ambit of the invention as is set forth in the following claims.
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An internal combustion engine ( 10 ) including at least two radial cylinders ( 17 ) disposed with their axes coplanar and equi-angular located relative to each other. The cylinders ( 17 ) meet to form a common combustion chamber ( 18 ). A piston ( 20 ) is located in each of the cylinders ( 17 ), each piston ( 20 ) cooperates with a cam profile ( 23 ) formed by the inner wall of a rotor ( 13 ). The cam profile ( 23 ) is rotationally symmetrical and includes the same number of lobes ( 26 ) as pistons ( 20 ) with each lobe ( 26 ) projecting radially inwards. The lobes are equi-angularly disposed about the inner wall of the rotor ( 13 ). In contrast to a conventional crankshaft driven engine, the cammed pistons ( 20 ) may move according to a non-sinusoidal time-velocity function. The lobes ( 26 ) may be modified in shape, for example, by filing or other reshaping, in order to customize the pattern of movement of the pistons ( 20 ) so as to alter the operating characteristics of the engine ( 10 ). In particular the lobes ( 26 ) may be re-shaped until an optimal efficiency is obtained.
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RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional Application No. 61/597,220 filed Feb. 10, 2012, which is hereby incorporated herein by reference.
FIELD OF INVENTION
[0002] The present invention relates generally to rotary valves, and more particularly to radially-ported rotary valves.
BACKGROUND
[0003] Compressed Air Energy Storage (CAES) is a way to store energy generated at one time for use at another time. At utility scale, energy generated during periods of low energy demand (off-peak) can be released to meet higher demand (peak load) periods. The storage vessel is often an underground cavern created by solution mining (salt is dissolved in water for extraction) or by utilizing an abandoned mine.
[0004] Large compression systems have been and are being developed to operate these storage/generation facilities. The compression systems in many cases are operated by hydraulic power and require high operating volumes of hydraulic fluid, a long life, and low leakage. These hydraulic systems would use hydraulic valving capable of handling this high volume of fluid flow with rapid actuation speeds.
SUMMARY OF INVENTION
[0005] The present invention provides a rotary valve capable of high flow rates, minimal pressure drop, and rapid actuation. The valves presented herein can be applied to a very large number of applications and can be scaled to any size.
[0006] According to one aspect of the invention, the rotary valve is characterized by a unique pressure balancing system operating on the rotary spool of the valve to reduce side force caused by pressure at the flow ports.
[0007] In particular, the rotary valve includes a housing having a cavity and a rotary spool positioned within and rotatably movable in the cavity of the housing about a rotation axis. The spool has a fluid passageway extending through the spool between first and second openings at an outer radial surface of the spool. The housing includes first and second flow ports opening to the cavity at radially spaced apart locations that respectively will align with the first and second openings at the outer radial surface of the spool at a first rotated position of the rotary spool. A first balancing port opens to the cavity at a side of the cavity radially opposite the first flow port. A balancing passageway communicates fluid pressure from the first flow port to the first balancing port.
[0008] Optionally, the rotary valve includes comprising a second balancing port opening to the cavity at a side of the cavity radially opposite the first flow port.
[0009] Optionally, the first and second balancing ports are directly opposite the first flow port and are axially offset from the first flow port and have a combined opening area approximately equal to the opening area of the first flow port.
[0010] Optionally, the housing has four flow ports and the rotary spool is moveable to a first position to create a fluid passageway between the first flow port and the second flow port, a second position to create a fluid passageway between a third flow port and a fourth flow port, and a third position blocking flow through the valve.
[0011] Optionally, the first balancing port is directly radially opposite the first flow port.
[0012] Optionally, the flow ports are formed perpendicular to a central axis of the cylindrical cavity.
[0013] Optionally, the balancing passageway is contained within the housing and fluidly connects the first flow port to the first balancing port.
[0014] According to another aspect of the invention, the rotary valve is characterized by a unique internal shiftable blocking spool in response to a failure condition or a modulating signal.
[0015] In particular, the rotary valve includes a housing having a cavity; a rotary spool positioned within and rotatably movable in the cavity of the housing about a rotation axis, the spool having a fluid passageway extending through the spool between first and second openings at an outer radial surface of the spool; and a second spool movable with respect to the rotary spool for restricting flow through the fluid passageway of the rotary spool. The housing includes first and second flow ports opening to the cavity at radially spaced apart locations that respectively will align with the first and second openings at the outer radial surface of the spool at a first rotated position of the rotary spool.
[0016] Optionally, the second spool is positioned in a bore through the rotary spool, intersects the fluid passageway, is movable within the bore.
[0017] Optionally, the second spool is configured to restrict flow through the fluid passageway in a first position and to not restrict flow through the fluid passageway in a second position.
[0018] Optionally, the second spool completely blocks flow through the fluid passageway when in the first position.
[0019] Optionally, the second spool is biased towards the first position.
[0020] Optionally, the second spool is axially moveable within the bore for selectively opening and closing the passageway.
[0021] Optionally, the axis of the bore and the second spool are perpendicular to the fluid passageway of the rotary spool.
[0022] Optionally, the bore and the second spool are axially disposed within the rotary spool.
[0023] According to another aspect of the invention, a unique interface is provided for sealing a port of a rotary valve to an outer surface of a rotary spool.
[0024] In particular, a seal for sealing includes a seal member having a central bore defining a fluid passageway along a flow axis, and having a sealing face for sealing against a rotary valve spool. The sealing face is concave along an axis perpendicular to the flow axis and thereby complimentary to an outer radial surface of the rotary spool.
[0025] Optionally, the seal is pressure balanced.
[0026] Optionally, the seal member is configured to produce a biasing force in a direction towards the sealing face when subject to pressurized fluid.
[0027] Optionally, the seal further includes a biasing element configured to bias the seal member in a direction towards the sealing face.
[0028] Optionally, the seal member is metal or a composite material.
[0029] According to another aspect of the invention, the rotary valve is characterized by a unique interface provided for sealing a port to an outer surface of the rotary spool.
[0030] In particular, the rotary valve includes a housing having a cavity; a rotary spool positioned within and rotatably movable in the cavity of the housing about a rotation axis, the spool having a fluid passageway extending through the spool between first and second openings at an outer radial surface of the spool; and a seal member having a fluid passageway along a flow axis, the seal member coaxial with and disposed in the first flow port and having a sealing face for sealing against the rotary spool. The housing includes first and second flow ports opening to the cavity at radially spaced apart locations that respectively will align with the first and second openings at the outer radial surface of the spool at a first rotated position of the rotary spool. The sealing face is concave along and concentric with the rotation axis of the rotary spool and thereby complimentary to an outer radial surface of the rotary spool.
[0031] Optionally, the seal member is pressure balanced.
[0032] Optionally, the seal member floats with respect to the housing.
[0033] Optionally, the seal member is configured to produce a biasing force in a direction towards the sealing face when subject to pressurized fluid.
[0034] Optionally, the rotary valve includes a biasing element configured to bias the seal member against the rotary spool.
[0035] Optionally, the seal member and the rotary spool form a metal-to-metal seal.
[0036] Optionally, the housing includes a passageway configured to communicate fluid pressure from the first flow port to a first balancing port opening to radially opposite side of the housing cavity from the first flow port; and the rotary valve further including a second seal member having a fluid passageway along a flow axis, the second seal member coaxial with and disposed in the first balancing port and having a sealing face for sealing against the rotary spool. The sealing face is concave along and concentric with the rotation axis of the rotary spool and thereby complimentary to the outer radial surface of the rotary spool.
[0037] Optionally, the rotary valve includes a second balancing port radially opposite the first flow port, and wherein the first and second balancing ports are axially offset from the first flow port and have a combined opening area approximately equal to the opening area of the first flow port; the rotary valve further including a third seal member having a fluid passageway along a flow axis, the third seal member coaxial with and disposed in the second balancing port and having a sealing face for sealing against the rotary spool. The sealing face is concave along and concentric with the rotation axis of the rotary spool and thereby complimentary to the outer radial surface of the rotary spool
[0038] According to another aspect of the invention, a rotary valve is characterized by a unique three-way three-or-more-position configuration.
[0039] In particular, the rotary valve includes a housing having a cavity; and a rotary spool positioned within and rotatably movable in the cavity of the housing about a rotation axis, the spool having a fluid passageway extending through the spool between first and second openings at an outer radial surface of the spool. The housing includes first, second, and third flow ports opening to the cavity at radially spaced apart locations. The rotary spool is movable between three positions, and wherein, in the first position, the rotary spool connects the first and second flow ports, in the second position, the rotary spool connects the second and third flow ports, and in the third position, the rotary spool disconnects the flow ports from each other.
[0040] Optionally, in a fourth position, the rotary spool connects the third and first flow ports.
[0041] According to another aspect of the invention, a rotary valve is characterized by a unique four-port three-position configuration.
[0042] In particular, the rotary valve includes a housing having a cavity; and a rotary spool positioned within and rotatably movable in the cavity of the housing about a rotation axis, the spool having a fluid passageway extending through the spool between first and second openings at an outer radial surface of the spool. The housing includes first, second, third, and fourth flow ports opening to the cavity at radially spaced apart locations. The rotary spool is movable between three positions, and wherein, in the first position, the rotary spool connects the first and third flow ports, in the second position, the rotary spool connects the second and fourth flow ports, and in the third position, the rotary spool disconnects the flow ports from each other.
[0043] The foregoing and other features of the invention are hereinafter described in greater detail with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0044] FIG. 1A shows a cross-section of an exemplary three-way rotary valve in one position;
[0045] FIG. 1B shows a cross-section of the exemplary three-way rotary valve in another position;
[0046] FIG. 1C shows a cross-section of the exemplary three-way rotary valve in yet another position;
[0047] FIG. 2A shows an exterior view of an exemplary four-port rotary valve;
[0048] FIG. 2B shows a cross-section of the exemplary four-port rotary valve;
[0049] FIG. 2C shows a schematic view of another exemplary four-port rotary valve;
[0050] FIG. 2D shows another schematic view of an exemplary four-port rotary valve;
[0051] FIG. 2E shows another schematic view of an exemplary four-port rotary valve;
[0052] FIG. 3A shows a side view schematic of an exemplary pressure-balanced rotary valve;
[0053] FIG. 3B shows a cross-sectional schematic of another exemplary pressure-balanced rotary valve;
[0054] FIG. 3C shows a cross-sectional schematic of yet another exemplary pressure-balanced rotary valve;
[0055] FIG. 4A shows a perspective view of an exemplary pressure-balanced rotary valve with interior housing features visible;
[0056] FIG. 4B shows a side view of the exemplary pressure-balanced rotary valve with interior housing features visible;
[0057] FIG. 4C shows another side view of the exemplary pressure-balanced rotary valve with interior housing features visible;
[0058] FIG. 5A shows a cross-sectional view of an exemplary rotary valve with pressure balanced port seals;
[0059] FIG. 5B shows a detail cross-sectional view of an exemplary rotary valve with pressure balanced port seals, detailing a view of a seal sealing to the rotary spool;
[0060] FIG. 6A shows a perspective view of an exemplary pressure balanced port seal;
[0061] FIG. 6B shows a side view of an exemplary pressure balanced port seal;
[0062] FIG. 7A shows a cross-sectional view of an exemplary rotary valve including a blocking spool;
[0063] FIG. 7B shows another cross-sectional view of the exemplary rotary valve including a blocking spool;
[0064] FIG. 7C shows yet another cross-sectional view of the exemplary rotary valve including a blocking spool;
[0065] FIG. 8 shows a hydraulic schematic showing the control circuit for operating the blocking spool;
DETAILED DESCRIPTION
[0066] A radially-ported rotary valve includes a central rotary spool that commutes flow therethrough between radially disposed stationary ports in a valve body or housing. Traditional rotary valves include spools that connect two ports together or, positioned between the ports, blocks the two ports from fluid communication.
[0067] Referring initially to FIGS. 1A-1C , shown is a 3 (or 4) position 3 way valve 100 having a valve housing 110 including a cavity 112 . A rotary spool 120 is positioned within and rotatably movable in the cavity of the housing about a rotation axis 122 . The spool 120 has a fluid passageway 125 extending through the spool between first and second openings 126 , 128 at an outer radial surface of the spool. The fluid passageway may include a sharp or a gradual (as shown) curve.
[0068] The housing 110 may include a plurality of flow ports 130 opening to the cavity 112 at radially spaced apart locations. In an exemplary embodiment, there are three flow ports 130 . Optionally, the flow ports 130 are equally spaced about the cavity 112 . The flow port 130 labeled “A” is the work port, the flow port 130 labeled “T” is the tank port, and the flow port labeled “P” is the supply pressure port. The function of the flow ports illustrated herein have been labeled for illustrative purposes, port hydraulic functions are not limited in any functional way.
[0069] By selectively positioning the rotary spool 120 , the work port can be connected via the fluid passageway 125 to one of the two service ports (supply pressure port, or tank port), or all flow ports 130 may be blocked by positioning the rotary spool 120 passageway 125 between any of the flow ports 130 . Furthermore, although not useful in all applications, the supply pressure port may also be connected to the tank port. Moreover, other configurations including any number of ports and inter-connections through the rotor are possible regardless of port function.
[0070] Turning now to FIGS. 2A and 2B , an exemplary embodiment of the rotary valve is shown at 200 . The rotary valve 200 is substantially the same as the above-referenced rotary valve 100 , and consequently the same reference numerals but indexed by 100 are used to denote structures corresponding to similar structures in the rotary valve. In addition, the foregoing description of the rotary valve 100 is equally applicable to the rotary valve 200 except as noted below. Moreover, it will be appreciated upon reading and understanding the specification that aspects of the rotary valves may be substituted for one another or used in conjunction with one another where applicable.
[0071] The rotary valve 200 includes a fourth flow port 220 opening to the cavity 212 . Although the four flow ports may be spaced as desired, an exemplary embodiment includes the four flow ports equally spaced at ninety degree intervals. In the exemplary embodiment, the fluid passageway 225 is straight, resulting in very little pressure drop across the valve 200 . Such a configuration results in a three-position valve. Specifically, the rotary spool 220 is movable between three positions. In the first position, the rotary spool 220 connects the first and third flow ports, in the second position, the rotary spool connects the second and fourth flow ports, and in the third position, the rotary spool disconnects the flow ports from each other. The two flow ports 230 labeled “A” are common work ports. By positioning the rotary spool 220 , the work port(s) can be connected to one of two service ports—herein shown as P (supply pressure), T (tank port)—or all ports may be blocked by positioning the fluid passageway 225 between any of the flow ports 230 .
[0072] This four port, three position configuration as described allows for a ‘straight through’ fluid passageway. This feature provides for the lowest pressure drop possible, because there are no turns or impingement points in the valve connecting any combination of ports.
[0073] FIGS. 2C-2E show another exemplary rotary valve. The rotary valve 200 ′ is substantially the same as the above-referenced rotary valve 200 , and consequently the same reference numerals but with prime notation are used to denote structures corresponding to similar structures in the rotary valve. In addition, the foregoing description of the rotary valve 200 is equally applicable to the rotary valve 200 ′ except as noted below. Moreover, it will be appreciated upon reading and understanding the specification that aspects of the rotary valves may be substituted for one another or used in conjunction with one another where applicable.
[0074] The rotary valve 200 ′ includes first and second fluid passages 225 ′ allowing the valve to connect, for example, a first work port (A) to tank (T) while simultaneously connecting the pressure supply port (P) to a second work port (B) in a first position. In a second position, A is connected to P while B is connected to T. Finally, in a third position, all flow ports are disconnected from each other.
[0075] An additional feature of the (4 ported) rotary valve described above is that in an application where the valve is required to cycle through a repetitive sequence of port connections where the flow ports can be arranged around the valve housing in the desired sequence. Such a valve can be continuously sequenced by positioning the rotary spool in a constant clockwise or counterclockwise direction without the need to reverse. This feature would prevent the generation of non-continuous wear in the rotor or body by any incorporated seals at the flow ports (for example, the floating pressure balanced seal rings, to be described later in this document). In applications where the valve positioning sequence is mostly a repeating sequence, the generation of these non-continuous wear grooves may not present an issue, but if during use the rotary spool is positioned over the end of such a groove, damage or excessive wear could be produced as well as an increase in seal leakage when the ‘worn-in’ seal is positioned over an unused portion of the rotary spool.
[0076] The flexibility of the above-described rotary valves allows any number of possible actuators to be attached to the rotary valve itself, including but not limited to electric, pneumatic, or hydraulic motors, manual operators, rotary actuators—all with the optional addition of gear boxes or leverage systems.
[0077] Actuation systems which operate the rotary valve can be configured as open loop where the valve operation and rotor position is limited (controlled) by physical stops in the valve, actuator, or gearbox mechanisms directly or by addition of additional mechanisms, or by manual means. Additionally the rotary spool position can be controlled within a closed loop system by a controller where the spool position is monitored and the actuator is controlled to position the spool to the desired spool position. Optionally, speed, acceleration, and jerk can also be controlled by said controller. In addition to controlling the spool position and motion performance, monitoring feedback either derived from the feedback means itself or separately by alternate position monitoring devices can be employed in practice to provide valve position status to a user's machine control system. Both the feedback for position control and optional said alternate position monitoring devices can be continuous or simply on/off. An exemplary embodiment would include a rotary continuous position transducer for closed loop positioning of the rotor, combined with proximity switches to be provided to the machine control user for process monitoring.
[0078] If port pressures where equal and symmetrically opposing across the rotary spool diameter while exerting over the same surface areas, then the resultant forces on the rotor would be balanced, but in use this would not be the case. Therefore, these potentially very large imbalanced forces would produce high frictional resistance to actuation, produce accelerated surface wear, or require very large bearings to support, or all mentioned.
[0079] Consider a single radial port with its associated area exposed to the rotary spool. By hydraulically connecting this port to an equal balancing area symmetrically disposed on the opposite side of the spool, the two opposite areas exposed to the same pressure will balance out with no reaction force on the spool. It is important to note that this balancing area may be symmetrically positioned to balance the opposing force across the rotor diameter, and additionally, this balancing area may be symmetrically disposed along the spool rotation axis as well. This balancing means can be used to balance any number of radial ports and result in a valve that does not require large (and/or many) bearings needed to support the rotary spool in the valve housing.
[0080] FIGS. 3A-3C show rotary valves 300 , 300 ′ and 300 ″ which include features that may be selectively incorporated into the other valves described herein in order to result in a pressure-balanced valve. Such a valve would result in significantly reduced transverse forces acting on the rotary spool when under pressure, allowing for significantly fewer/smaller bearings to support the spool in the housing.
[0081] As shown, the housing may include one or more balancing ports 370 opening to the cavity 312 at a side of the cavity radially opposite an associated flow port 330 . A balancing passageway 375 may communicate fluid pressure from the flow port 330 to the associated balancing port 370 .
[0082] The location and size of the one or more balancing ports may be adjusted to produce the desired effect. In an exemplary embodiment, the one or more balancing ports 370 are radially opposite the associated flow port 330 .
[0083] Although the area of any balancing ports may be any desired amount, in an exemplary embodiment, the area is approximately equal to the area of the associated flow port 330 . This equivalence in area, combined with an approximate equivalence in pressure, results in an equal and opposite force from the balancing port 370 , tending to cancel out the force of the pressure acting on the rotary spool at the associated flow port 330 .
[0084] Optionally, the housing may include more than one balancing port associated with each flow port. In an exemplary embodiment, the housing includes two balancing ports 370 per associated flow port 330 , as is shown in FIG. 3A . The two balancing ports 370 may be directly radially opposite the first flow port and may be axially offset from the associated flow port 330 . Being axially offset allows the balancing ports 370 to avoid fluid communication with the fluid passageway 325 of the rotary spool 320 . Being of equal total area to each other and of equal axial spacing from the associated flow port 330 makes the net torque about the rotary spool rotation axis on the rotary spool 320 produced by the balancing ports 370 approximately zero. Alternatively, such a result may be achieved through other means, for example by unequal areas and concomitantly unequal spacing, as long as the sum of all the moments produced by the balancing ports disposed about the associated flow ports axis sum to zero.
[0085] The balancing passageway 375 may include porting connected via external connections. Alternatively, the passageway may include one or more channels contained within the housing of the valve, as shown in FIGS. 4A-4C .
[0086] As shown, such a balancing system as described above may be applied to variously-configured rotary valves. FIG. 3B shows the system applied to a four port, three position rotary valve in which each of the four flow ports (P, T, A1 and A2) have one or more associated balancing ports, resulting in a fully pressure balanced rotary valve. However, not every flow port needs to be balanced with one or more balancing ports in every application. For example, in some systems, one or more flow ports (e.g., the tank port) may have zero or negligible pressure acting on the rotary spool. Therefore, in such a case, the tank port would not need to be balanced in order to balance the rotary valve as a whole.
[0087] In the case where no or minimal clearance is maintained between the rotary spool and the housing, guided or otherwise—where the rotary spool and the housing can come into contact with one another—frictional forces and component wear will be produced. In the case where the rotary spool and the housing's clearance is guided and controlled, the clearance itself may provide an undesirable inter-port leak path and subsequent leakage. In the case where the rotary spool is exposed to unbalanced forces, such as produced by port pressures or other sources, the deflection of the spool will have to be taken into account to provide adequate additional clearance to keep the spool from contacting the housing in use. In this last case the inter-port leakage will be exacerbated. The dimensional control requirements for any of the three cases identified would be critical, and the expense to minimize inter-port leakage and/or unnecessary wear could be unpractical, although such a configuration is still within the scope of this invention and may be employed in some applications.
[0088] Referring now to FIGS. 5A , 5 B, 6 A, and 6 B, an exemplary embodiment implements radially disposed floating pressure balanced floating shear seals 580 contained in the housing 510 at each port location. Sealing faces 581 are in contact with the rotating spool 520 and provide a seal between the rotary spool 520 and the stationary housing 510 regardless of the clearance between the two. This reduces the inter-port leakage while allowing a more practical (larger) clearance between the spool and body. This embodiment also allows the rotary spool to be guided by a bearing means maintaining the said practical clearance assuring that the rotor does not contact the housing, thus mitigating the potential for wear between the spool and body.
[0089] The floating pressure balanced shear seals 580 are configured in such a way that the differential area across the seal (as radially disposed for the seal face to contact the rotor) is slightly unbalanced to create a bias force, energized by the port pressure, toward the rotary spool 520 . For example, the inlet diameter (D inlet ) of the seal would be slightly larger than the outlet diameter (D outlet ) of the seal. A spring 582 may optionally be used instead of or in addition to the pressure biasing. The spring 582 rest in a spring groove 584 and may assist by overcoming the seals' diametral o-ring friction when the available port pressure is not high enough to overcome this force. This pressure-energized force unbalance (pressure biasing) in conjunction with the spring should be sufficient to substantially overcome the seals' diametral o-ring friction and assure the seal follows the profile of the rotary spool 520 .
[0090] The seal imbalance in itself can be of any magnitude. However, larger unbalanced areas will produce significantly higher friction resulting in higher required torque to operate the valve and will produce accelerated wear. In an exemplary embodiment, the floating pressure balanced shear seals 580 are for the most part more balanced than imbalanced, as the intent is to provide only enough reliable force between the individual seals and the rotary spool to ensue enough contact during all operating conditions to assure a good seal while avoiding unnecessary frictional force and subsequent required actuator torque to operate the valve. This ‘nearly’ balanced feature also minimizes seal and rotary spool wear to levels well below conventional sealing systems and will produce much longer life.
[0091] The seals described herein may be, and are herein presented as being, used on either flow ports or balancing ports. The fluid passageway through the seal defines a flow axis 583 . In order to properly seal with the outer surface of the rotary spool 520 , the sealing face 581 is concave along and concentric with the rotation axis 524 of the rotary spool 520 and is thereby complimentary to the outer radial surface of the rotary spool 520 .
[0092] Preferably, the seal member 580 is metal or a composite, thus forming a robust (e.g., metal-to-metal) seal with the rotary spool. The durability of a metal seal will allow for significantly reduced maintenance and longer life. Because the seal itself moves little, the seal member 580 may be sealed to the housing along an outer diameter with an O-ring 586 situated in a channel 587 .
[0093] Although the configuration described herein refers to seal members located in the housing and sealing against the rotary spool, it is contemplated that the seals may also be located in the rotary spool and seal against the inside of the housing.
[0094] In any event requiring a failsafe function where any of the described rotary valves is required to fail in an “all ports blocked condition” where the primary actuator cannot be relied upon to produce this result, or in any a condition where the valve actuator is required to be overridden, an integrated ‘Failsafe Port Blocker’ may be incorporated.
[0095] Referring to FIGS. 7A-7C , a second spool or blocking cylinder 790 is included and may optionally be positioned and keyed concentrically within a bore 721 of the rotary spool 720 as shown, where a through passage 791 in the blocking cylinder is aligned with the rotary spool fluid passage 725 under normal conditions.
[0096] When the failsafe condition is required, the hydraulic volume 792 holding the blocker in the open position may be allowed to vent to tank and the spring 793 moves the blocker, thus blocking flow through the rotary spool. Regardless of the position of the rotary spool 720 when the failsafe is initiated, all ports will be blocked. Although shown as an axially movable spool 790 , the blocker spool may also be implemented in other way, including as a rotary spool, rotatably movable with respect to the rotary spool 720 .
[0097] During normal operation the valve 700 may be held in the blocked position until the hydraulic operator volume 792 opposing the spring is pressurized and the blocker spool 790 is disabled by moving to the position allowing communication through the rotary spool and blocker spool. As long as the hydraulic operator is pressurized—the blocker function is neutralized. Upon electrical power failure or when a signal to a directional pilot valve solenoid is disconnected, a cartridge valve may vent the hydraulic operator holding the blocker in place and the blocker will move to the blocked position.
[0098] This blocking function and the associated fixtures can be performed either integrated in the valve itself or separately plumbed to the rotary valve, or may include a combination of these alternatives. The configuration shown is to illustrate the blocking principle itself and the means for actuation. Several alternate configurations are possible.
[0099] Referring to FIG. 8 , starting with the blocker cylinder in the blocked position and with the power to the ‘lift’ solenoid of the pilot control directional control valve off, the solenoid valve vents the back side of the DIN cartridge valve providing no resistance to flow to the top of the blocker actuator. The blocked actuator remains bottomed out by the blocker spring. To move the blocker to the ‘normal’ operating (non blocked) position, the ‘lift’ solenoid is energized, moving the spool connecting supply pressure to the blocker actuator, which moves the blocker against the spring until the blocker actuator bottoms, thus positioning the blocker in the ‘normal’ unblocked position. As long as the ‘lift’ solenoid is energized, the blocker remains in the ‘normal’ unblocked position. Upon a power or hydraulic supply failure the pilot control directional valve will spring activate the spool to the position where the supply pressure port will be blocked, and the back side of the DIN cartridge valve will vent to tank, allowing the stored hydraulic pressure in the blocker actuator to flow through the nose of the DIN cartridge valve to tank, thus positioning the blocker in the ‘blocked’ position.
[0100] In addition to acting only or primarily as a failsafe blocking spool, the second spool may respond to a modulating signal and be used to regulate the amount of fluid flowing through the rotary spool when the rotary spool is in an open position.
[0101] When used in large applications, the force required to actuate the rotary spool of the valve may become restrictive. Therefore, in order to provide an adequate flow in a relatively small package, any of the rotary valves described herein may be modified into a stacked arrangement with coupled or shared rotary spools.
[0102] Although the invention has been shown and described with respect to a certain embodiment or embodiments, it is obvious that equivalent alterations and modifications will occur to others skilled in the art upon the reading and understanding of this specification and the annexed drawings. In particular regard to the various functions performed by the above described elements (components, assemblies, devices, compositions, etc.), the terms (including a reference to a “means”) used to describe such elements are intended to correspond, unless otherwise indicated, to any element which performs the specified function of the described element (i.e., that is functionally equivalent), even though not structurally equivalent to the disclosed structure which performs the function in the herein illustrated exemplary embodiment or embodiments of the invention. In addition, while a particular feature of the invention may have been described above with respect to only one or more of several illustrated embodiments, such feature may be combined with one or more other features of the other embodiments, as may be desired and advantageous for any given or particular application.
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A rotary valve capable of high flow rates, minimal pressure drop, and rapid actuation is presented. According to one aspect, the rotary valve is characterized by a unique pressure balancing system operating on the rotary spool of the valve to reduce side force caused by pressure at the flow ports. According to another aspect, the rotary valve ( 700 ) is characterized by a internal shiftable blocking spool ( 790 ) in response to a failure condition or a modulating signal. According to another aspect, an interface is provided for sealing a port of a rotary valve to an outer surface of a rotary spool. According to another aspect, the rotary valve is characterized by an interface provided for sealing a port to an outer surface of the rotary spool. According to another aspect, a rotary valve is characterized by a three-way three-or-more-position configuration. According to another aspect, a rotary valve is characterized by a four-port three-position configuration.
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CROSS REFERENCE TO RELATED APPLICATIONS
The present application is a divisional of U.S. patent application Ser. No. 12/306,706, filed Jul. 20, 2009 now U.S. Pat. No. 8,246,975, which is a U.S.C. §371 National Phase conversion of PCT/JP2007/063011, filed Jun. 28, 2007, which claims benefit of Japanese Application No. 2006-177971, filed Jun. 28, 2006 and Japanese Application No. 2007-056624, filed Mar. 7, 2007, the contents of which are incorporated in full herein by reference. The PCT International Application was published in the Japanese language.
The present application is also a continuation-in-part of U.S. patent application Ser. No. 12/063,768, filed Feb. 14, 2008 now abandoned, which is a U.S.C. §371 National Phase conversion of PCT/JP2006/317027, filed Aug. 23, 2006, which claims benefit of Japanese Application No. 2005-251190, filed Aug. 31, 2005 and Japanese Application No. 2006-177971, filed Jun. 28, 2006, the contents of which are incorporated in full herein by reference. The PCT International Application was published in the Japanese language.
FIELD OF THE INVENTION
The present invention relates to a drug, a drug guidance system, a magnetic detection system, and a drug design method.
BACKGROUND
Generally, drugs administered to the living body reach target sites and cause therapeutic effects by exerting pharmacological effects at the localized target sites. However, there will not be a cure if drugs reach tissues other than the target sites (that is, normal tissues). Consequently, how to guide drugs to the target sites efficiently is important in terms of therapeutic strategy. Such a technology for guiding drugs to the target sites is called drug delivery and research and development thereof have been actively carried out in recent years. These drug delivery methods have at least two merits. One is that a sufficiently high drug concentration is obtained in affected tissues. This is advantageous because pharmacological effects are achieved only when the drug concentration in the target site is higher than a certain value, and therapeutic effects can not be expected when the concentration is low. Second is that the drug delivery methods guide drugs to affected tissues only and do not guide drugs to normal tissues unnecessarily. Side effects can thereby be suppressed.
Such drug delivery methods exert their effects most in cancer treatments using anticancer agents. Since most anticancer agents suppress cell growth of cancer cells which are actively dividing, they also suppress cell growth in normal tissues where cells are actively dividing such as, for example, bone marrow, hair-roots, or gastrointestinal mucosa. On this account, side effects such as anemia, hair loss, and vomiting appear in cancer patients who have received administration of anticancer agents. Dosage has to be restricted since these side effects would be heavy burdens on patients and thus, there is a problem in that pharmacological effects of anticancer agents cannot be obtained sufficiently. Furthermore, there is a concern of patients dying due to the side effects in worst cases. Accordingly, it is hoped that cancer treatments can be carried out efficiently while suppressing the side effects by guiding the anticancer agents until they reach cancer cells with drug delivery methods and allowing the agents to exert their pharmacological effects on cancer cells, specifically.
Apart from anticancer agents, for example, application of the drug delivery methods to agents for treating male erectile dysfunction is considered. There are examples of significant systemic hypotension resulting in deaths caused by the use of agents for treating male erectile dysfunction when combined with nitro preparations and thus, it is a problem particularly for males of middle and old age with heart disease. This is because the agents for treating erectile dysfunction do not necessarily concentrate at the target site, act on systemic blood vessels, and thereby increase vasodilation effects of nitro preparations. Accordingly, it is considered that the side effects resulting from the combined use with nitro preparations can be suppressed by guiding the agents for treating male erectile dysfunction until they reach the target site with drug delivery methods and allowing the agents to exert their pharmacological effects on the target site specifically.
As a specific method of drug delivery methods, for example, guidance to the target site using supports (carriers) is being studied and this method is to load drugs onto supports that tend to concentrate in the target site and thereby make the supports transport the drugs to the target site. As supports, use of various types of antibodies, microspheres, or magnetic bodies has been discussed. Among them, magnetic bodies are those that are regarded as particularly hopeful and a method to attach the supports, which are magnetic bodies, to the drugs and make them accumulate in the target site by means of a magnetic field has been examined (for example, refer to the following Patent Document 1). Since this guiding method is easy and simple and makes treatment which targets the target site possible, it is considered to be an effective method especially for anticancer agents with high cytotoxicity.
Patent Document 1: Japanese Laid-Open Patent Application No. 2001-10978
BRIEF SUMMARY OF THE INVENTION
However, when the supports, which are magnetic bodies, are used as carriers as described above, difficulties in oral administration, the large size of carrier molecules in general, or technical problems in bond strength and affinity with the drug molecules have been pointed out and thus, practical application has been difficult.
The present invention addresses the abovementioned problems, with an object of realizing a drug delivery system which is capable of solving conventional technical problems and which is easy to put into practical application.
In order to achieve the above object according to a first aspect of the present invention relating to a drug, the drug is composed of an organic or inorganic compound, and is made magnetic by modification of side chains and/or crosslinking between side chains.
According to a second aspect of the present invention relating to a drug, the organic compound in the first aspect is forskolin.
Moreover, as a third aspect of the present invention relating to a drug according to the first aspect, the organic compound is a composition effective in the treatment of male erectile dysfunction.
Moreover, as a fourth aspect of the present invention relating to a drug according to the first aspect, the inorganic compound is a metal complex.
Moreover, as a fifth aspect of the present invention relating to a drug according to the fourth aspect, the metal complex is a cis geometric isomer with anticancer properties.
Moreover, as a sixth aspect of the present invention relating to a drug according to the fifth aspect, the cis geometric isomer is cisplatin.
Moreover, as a first aspect of the present invention relating to a drug guidance system, a drug of any one of the above first to sixth aspects administered to a body is guided to a predetermined target site using the magnetism of the drug.
Moreover, as a first aspect of the present invention relating to a magnetic detection system, by detecting magnetism of a drug of any one of the above first to sixth aspects administered in a body, the dynamics of the drug are detected.
Moreover, as a first aspect of the present invention relating to a drug design method, a molecular model having modified side chains and/or crosslinked side chains is set with respect to an organic or inorganic compound used as a drug; whether or not the molecular model is magnetic is determined from a spin-charge density distribution obtained by a numerical calculation for the molecular model; and then the drug is designed based on the molecular model that has been determined to be magnetic.
Moreover, as a second aspect of the present invention relating to a drug design method according to the first aspect, whether the molecular model is ferromagnetic or ferrimagnetic is determined based on the spin-charge density distribution.
Moreover, as a third aspect of the present invention relating to a drug design method according to in the first aspect, the magnetic strength of the molecular model is determined based on the spin-charge density distribution.
According to the present invention, since drugs themselves will be magnetic, it is possible to guide the drugs to the target sites in the body by use of magnetism of the drugs themselves without using supports made from magnetic bodies as in the conventional cases. As a result, conventional problems such as difficulties in oral administration, the large size of carrier molecules in general, or technical problems in bond strength and affinity with the drug molecules can be resolved. Furthermore, it is possible to realize a drug delivery system which is easy to put into practical application.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagram of a basic molecular structural model of forskolin in one embodiment of the present invention.
FIG. 2 is a diagram of a molecular structural model of a ferrimagnetic forskolin derivative A in one embodiment of the present invention.
FIG. 3 is a diagram showing a three-dimensional molecular structural model of the forskolin derivative A and its spin-charge density distribution, in one embodiment of the present invention.
FIG. 4 is a diagram of a molecular structural model of a ferromagnetic forskolin derivative B in one embodiment of the present invention.
FIG. 5 is a diagram showing a three-dimensional molecular structural model of the forskolin derivative B and its spin-charge density distribution, in one embodiment of the present invention.
FIG. 6 is a flow chart of a drug design method in one embodiment of the present invention.
FIG. 7 shows a diagram of a basic molecular structural model of PDE 5 inhibitor with a standard composition and a three-dimensional molecular structure and spin-charge density distribution of the PDE 5 inhibitor with a standard composition in one embodiment of the present invention.
FIG. 8 shows a diagram of a basic molecular structural model of a derivative of PDE 5 inhibitor and a three-dimensional molecular structural model and spin-charge density distribution of the derivative of PDE 5 inhibitor in one embodiment of the present invention.
FIG. 9 is a diagram of a basic molecular structural model of cisplatin in one embodiment of the present invention.
FIG. 10 shows a diagram of a basic molecular structural model of a cisplatin derivative (Cis-Pt-a3) and a three-dimensional molecular structural model and spin-charge density distribution of the cisplatin derivative (Cis-Pt-a3) in one embodiment of the present invention.
FIG. 11 is an analytical result of spin-charge densities of a cisplatin derivative and a derivative derived by the substitution of platinum of the cisplatin derivative into another metal element in one embodiment of the present invention.
FIG. 12 is a diagram of a basic molecular structural model of the cisplatin derivative NK121, and its three-dimensional molecular structural model and spin-charge density distribution in one embodiment of the present invention.
FIG. 13 is a diagram showing a hydrolysis process of cisplatin in a living body in one embodiment of the present invention.
FIG. 14 is a diagram of a three-dimensional molecular structural model and spin-charge density distribution of the cisplatin hydrolysate [Pt(OH 2 ) 2 (dien)] 2+ in one embodiment of the present invention.
FIG. 15 is a first example of a computer output screen indicated by the computer simulation program during the process of calculating the spin-charge density of the target compound.
FIG. 16 is a second example of a computer output screen indicated by the computer simulation program during the process of calculating the spin-charge density of the target compound.
FIG. 17 is a diagram illustrating the principle of MRI.
FIG. 18 is a perspective view of the entire MRI system.
FIG. 19 shows MRI output images of an example in which a magnetic drug is administered to a rat.
FIG. 20 is an MRI output image showing that MRI images are dependent on the concentration of a target drug.
FIG. 21 is a block diagram illustrating the outline of an experiment system for verifying the location of a drug in a magnetic field.
FIG. 22 is a chart showing characteristics of the measurement results of the number of cells in accordance with fluctuations in the drug concentration in a magnetic field.
FIG. 23 is a perspective view illustrating another embodiment of a guidance system according to the present invention.
FIG. 24 is a graph showing the MRI measurement results on mouse kidneys.
DESCRIPTION OF REFERENCE SYMBOLS
A, B: forskolin derivatives
DETAILED DESCRIPTION OF THE INVENTION
Hereunder is a description of one embodiment of the present invention, with reference to the drawings.
First Embodiment
Firstly, the first embodiment is described using an organic compound, more specifically, forskolin, as a drug candidate agent.
FIG. 1 is a diagram showing a basic molecular structural model of forskolin. In this drawing, R 6 , R 7 , and R 13 show positions bonded with an atom or a molecule for modifying a side chain of forskolin. Depending on the type of atom or molecule bonded to these positions, the physical property of forskolin varies. In this drawing, one having H bonded to R 6 , CH 3 bonded to R 7 , and CH═CH 2 bonded to R 13 is naturally occurring forskolin, and one having the side chain structure changed artificially, that is, forskolin produced by changing the atom or molecule for modifying R 6 , R 7 , and R 13 , is called a forskolin derivative. In FIG. 1 , C 1 to C 13 represent a carbon atom (C).
FIG. 2 is a diagram showing a basic molecular structural model of a magnetic (ferrimagnetic) forskolin derivative A. As shown in this drawing, the forskolin derivative A is one where R 6 of the abovementioned naturally occurring forskolin is changed into COCH 2 CH 2 NCH 3 , R 7 is changed to CH 3 , and the oxygen atom (O) bonded to C 9 and the carbon atom bonded to C 13 are crosslinked.
FIG. 3 shows a three-dimensional molecular structure of the forskolin derivative A ad its spin-charge density distribution obtained by a computer simulation based on a well-known first principle molecular dynamics method. The first principle molecular dynamics method is disclosed in Delley, B. J. Chem. Phys., 1990, 92, 508-517, Delley, B. J. Chem. Phys., 2000, 113, 7756-7764, Haselgrove, C. B. Math Comp., 1961, 15, 323-337, Ellis, D. E. Int. J. Quantum Chem., 1968, 2S, 35-42, Ellis, D. E.; Painter, G. S. Phys. Rev. B, 1970, 2, 2887-2898.
In FIG. 3 , region 1 shows a downward spin-charge density, and regions 2 to 5 show upward spin-charge densities. These regions are selected because, as a result of calculation of a contour line of the spin-charge densities, these region show high spin-charge densities. The property of magnetism of a compound is decided by balance between upward spin and downward spin. Therefore, as shown in FIG. 2 , since a downward spin state 1 ′ and upward spin states 2 ′ to 5 ′ are mixed in the forskolin derivative A, it is found to be a ferrimagnetic body.
On the other hand, FIG. 4 is a diagram showing a basic molecular structural model of a magnetic (ferromagnetic) forskolin derivative B. As shown in this drawing, the forskolin derivative B is one where R 6 of the abovementioned naturally occurring forskolin is changed into COCH 2 CH 2 NCH 3 , R 7 is CH 3 , R 13 is changed into CH—CH 2 —CH 3 , and the oxygen atom bonded to C 9 and the carbon atom bonded to C 13 are crosslinked.
Similarly to the above, FIG. 5 shows a three-dimensional molecular structure of the forskolin derivative B and its spin-charge density distribution obtained by a computer simulation based on the first principle molecular dynamics method. In FIG. 5 , regions 10 to 12 show upward spin-charge densities. Therefore, as shown in FIG. 4 , since only upward spin states 10 ′ to 12 ′ are present in the forskolin derivative B, it is found to be a ferromagnetic body.
In this manner, by modifying the side chains of forskolin with specified atoms or molecules, and crosslinking between side chains present in predetermined positions, a magnetic forskolin derivative, that is, a drug, can be produced. The portion indicated with a dashed line in FIG. 2 is crosslinked. In this way, the magnitude of the magnetism of the drug can be controlled by modifying the side chains of the drug with specified atoms or molecules and/or crosslinking the side chains existing at specified positions. A user can decide as appropriate, by means of computer simulation, which functional group to insert or what form of crosslinking should be applied.
A system for realizing this computer simulation is equipped with known hardware resources for a computer: in other words, the system includes memory, an arithmetic unit with arithmetic circuits such as CPU, and display means for outputting arithmetic results. The memory stores data for specifying the three-dimensional structure of existing organic compounds and inorganic compounds and software programs for realizing the computer simulation. The software can add, change, or delete the side chains of each compound, crosslink specified side chains, calculate regions with high spin-charge densities as described above, and determine the spin-charge density of the entire structure. As such a program, for example, a commercially available product (DMOL3™ made by Accelrys K.K.) can be used.
The user inputs the position(s) to add side chains, changes the side chains, or selects the side chains to be deleted; and the user further designates the position(s) to form crosslinks to the arithmetic unit using a support program for the memory. Receiving such input values, the arithmetic unit calculates the spin-charge density and outputs the results to a display screen. Moreover, the user can find the spin-charge density of an existing compound by adding structural data of the existing compound to the computer system.
Next, a method for designing such a magnetic drug will be explained below. FIG. 6 is a flow chart showing a processing procedure of the present drug design method. The processing described hereunder is performed in a computer simulation program based on the first principle molecular dynamics method.
Firstly, since there are more than 200 types of forskolin derivatives used as drugs, a forskolin derivative serving as an evaluation target is selected from among them, and its chemical formula is input into the computer simulation program (step S 1 ). Here, a case where the abovementioned forskolin derivative A is selected as the forskolin derivative is assumed and described hereunder. A derivative of each type of these compounds is identified by a compound library created in advance. The user inputs' the atomic number and position of each atom of each compound to the arithmetic unit.
FIG. 15 shows screens displayed on the output device during operation in step 1 . As shown in FIG. 15 ( 1 ), the atomic number and atomic coordinates of one atom are input. As shown in FIG. 15 ( 2 ), the bonded state of atoms such as a single bond, a double bond, or a triple bond is specified by placing a cursor at the relevant position and clicking the cursor.
The arithmetic unit receiving the above input sets, based on the above-mentioned program, initial values of upward spin (spin up) wave function φ↑(r), downward spin (spin down) wave function φ↓(r), spin-up effective potential v↑(r), spin-down effective potential v↓(r), spin-up charge density ρ↑(r), and spin-down charge density ρ↓(r) (step S 2 ). Here, r is a variable showing the coordinates in the three-dimensional space.
In a case where the respective atoms constituting the forskolin derivative A are present as an isolated atom in the three-dimensional space, the spin-up wave functions φ↑(r) are obtained for each of the respective atoms. The initial value of the spin-up wave function φ↑(r) is the sum of all the spin-up wave functions φ↑(r) that have been obtained in such a manner.
Similarly, the initial value of the spin-down wave function φ↓(r) is the sum of all the spin-down wave functions φ↓(r) obtained for each of the respective atoms, in a case where the respective atoms are present as an isolated atom in the three-dimensional space. Moreover, based on the spin-up wave functions φ↑(r) in a case where the respective atoms constituting the forskolin derivative A are present as an isolated atom in the three-dimensional space, the spin-up effective potentials v↑(r) are obtained for each of the respective atoms. The initial value of the spin-up effective potential v↑(r) is the sum of all the spin-up effective potentials v↑(r) that have been obtained for each of the respective atoms. Similarly, the initial value of the effective potential v↓(r) is the sum of all the spin-down effective potentials v↓(r) obtained for each of the respective atoms based on the spin-down wave functions φ↓(r) in a case where the respective atoms are present as an isolated atom in the three-dimensional space.
Moreover, the initial value of the spin-up charge density ρ↑(R) is obtained by substituting the spin-up wave functions φ↑(r) that have been obtained for each of the respective atoms as mentioned above, into the following operational expression (1). Moreover, the initial value of the spin-down charge density ρ↓(r) is obtained by substituting the spin-down wave functions φ↓(r) that have been obtained for each of the respective atoms, into the following operational expression (2). In the following operational expression (1), φ↑(r) is a conjugate complex number of the spin-up wave function φ↑(r). In the following operational expression (2), φ↓*(r) is a conjugate complex number of the spin-down wave function φ↓(r).
[Equation 1]
ρ ↑ ( r )=ΣΦ ↑ *( r )Φ ↑ ( r ) (1)
ρ ↓ ( r )=ΣΦ ↓ *( r )Φ η ( r ) (1)
Next, based on the initial values of the spin-up effective potential v↑(r) and the spin-down effective potential v↓(r), and the initial values of the spin-up charge density ρ↑(r) and the spin-down charge density ρ↓(r), the following Kohn-Sham equations (3) and (4) are solved, so as to calculate the spin-up wave function φ↓(r), the spin-down wave function φ↓(r), the spin-up energy eigenvalue ε↑, and the spin-down energy eigenvalue ε↓, of the forskolin derivative A (step S 3 ).
[Equation 2]
[−½∇ 2 +V ↑ {r ,ρ ↑ ( r )}]Φ ↑ ( r )=ε ↑ Φ ↑ ( r ) (3)
[−½∇ 2 +V ↓ {r ,ρ ↓ ( r )}]Φ ↓ ( r )=ε ↓ Φ ↓ ( r ) (3)
Then, based on the spin-up wave function φ↑(r) and the spin-down wave function φ↓(r) of the forskolin derivative A obtained in step S 3 , the spin-up charge density ρ↑(r), the spin-down charge density ρ↓(r), the spin-up effective potential v↑(r), and the spin-down effective potential v↓(r) of the forskolin derivative A are calculated (step S 4 ). It is then determined whether or not these spin-up charge density ρ↑(r) and spin-down charge density ρ↓(r) are the same as the previous values of the spin-up charge density ρ↑(r) and the spin-down charge density ρ↓(r), which are the initial values in this case (step S 5 ). In this step S 5 , if it is determined “NO”, that is, the previous values (initial values) of the spin-up charge density ρ↑(r) and the spin-down charge density p↓(r) are not the same as the present values obtained in step S 4 , then the spin-up effective potential v↑(r), the spin-down effective potential v↓(r), the spin-up charge density ρ↑(r), and the spin-down charge density ρ↓(r) obtained in step S 4 are set as new initial values (step S 6 ). Then the flow proceeds to step S 3 , and the Kohn-Sham equations (3) and (4) are solved again, so as to calculate a new spin-up wave function φ↑(r), spin-down wave function φ↓(r), spin-up energy eigenvalue ε↑, and spin-down energy eigenvalue ε↓. That is, in step S 5 , the processing from steps S 3 to S 6 is repeated until the previous values of the spin-up charge density ρ↑(r) and the spin-down charge density ρ↓(r) become equal to the present values, to thereby obtain the spin-up wave function φ↑(r), the spin-down wave function φ↓(r), the spin-up energy eigenvalue ε↑, and the spin-down energy eigenvalue ε↓(r) which satisfy the Kohn-Sham equations (3) and (4).
On the other hand, in step S 5 , if it is determined “YES”, that is, the previous values of the spin-up charge density ρ↑(r) and the spin-down charge density ρ↓(r) are the same as the present values, then as described above, an interatomic force acting between respective atoms is calculated, based on the spin-up wave function φ↑(r), the spin-down wave function φ↓(r), the spin-up energy eigenvalue ε↑, and the spin-down energy eigenvalue ε↓(r) which satisfy the Kohn-Sham equations (3) and (4), and the structure of the forskolin derivative A is optimized (step S 7 ). That is, the spin-up wave function φ↑(r), the spin-down wave function φ↓(r), and so forth that have been obtained by repeating steps S 3 to S 6 , are merely the optimum values in a model on a two-dimensional plane as shown in FIG. 2 , and in practice it is necessary to consider the structure of the forskolin derivative A in the three-dimensional space.
Specifically, in step S 7 , the respective atoms constituting the forskolin derivative A are moved for a predetermined distance in an optimum direction assumed from the spin-up wave function φ↑(r), and the spin-down wave function φ↓(r), in the three-dimensional space, and an interatomic force acting between the respective atoms at this time is calculated. If the interatomic force at this time becomes 0 and the respective atoms no longer move, it can be determined that the structure of the forskolin derivative A is optimized. Therefore, the interatomic force acting between the respective atoms after the movement is calculated, and it is, determined whether or not the interatomic force becomes 0 (step S 8 ).
In this step S 8 , if it is determined “NO”, that is, the interatomic force is not 0 and the structure is not optimized, then the spin-up wave functions φ↑(r) and the spin-down wave functions φ↓(r) in the structures of the respective atoms after the movement are obtained. Then, the spin-up effective potential v↑(r), the spin-down effective potential v↓(r), the spin-up charge density ρ↑(r), and the spin-down charge density ρ↑(r) obtained from the spin-up wave function φ↑(r) and the spin-down wave function φ↓(r) are set as new initial values (step S 9 ), and the processing from steps S 3 to S 8 is repeated. Here, the reason the flow returns to step S 3 is that the spin-up wave function φ↑(r) and the spin-down wave function φ↓(r) are changed according to the structural change of the respective atoms after the movement. Moreover, the structures of the respective atoms after the movement are memorized, and when step S 7 is performed again, the respective atoms are moved again for a predetermined distance from the previous structure.
When the structure of such a forskolin derivative A is optimized, then as shown in FIG. 2 , the three-dimensional structure is forcibly altered so as to crosslink the oxygen atom bonded to C 9 and the carbon atom bonded to C 13 . The atoms selected for such a crosslinking can be optionally changed.
On the other hand, in this step S 8 , if it is determined “YES”, that is, the interatomic force acting between the respective atoms becomes 0 and the structure of the forskolin derivative A is optimized by, for example, Jahn-Teller effect, then the spin-charge density distribution as shown in FIG. 3 is obtained, based on the spin-up wave function φ↑(r) and the spin-down wave function φ↓(r) in the optimized structure (step S 10 ).
Here, depending on the forskolin derivative selected as the evaluation target, the spin-charge density distribution such as regions 1 to 5 shown in FIG. 3 is not generated, or if the spin-charge density distribution is generated, regions having only a very small amount of spin-charge density (that is magnetic strength) are present. Such a forskolin derivative can not be determined to be magnetic. Consequently, based on the spin-charge density distribution, firstly it is determined whether or not the forskolin derivative selected as the evaluation target is magnetic (step S 11 ).
In step S 11 , if it is determined “NO”, that is, the forskolin derivative selected as the evaluation target is not magnetic, the flow proceeds to step S 1 , and another forskolin derivative is newly selected and the magnetism is evaluated again. On the other hand, in step S 11 , if it is determined “YES”, that is, the forskolin derivative selected as the evaluation target is magnetic, then it is determined whether it is ferromagnetic or ferrimagnetic, based on the spin-charge density distribution (step S 12 ).
As described above, since the spin-charge density distribution shows the distribution of the spin-up charge density and the spin-down charge density; if these spin-up charge density and spin-down charge density are mixed, it can be determined to be ferrimagnetic. If only one of the spin-up charge density and the spin-down charge density is present, it can be determined to be ferromagnetic.
As shown in FIG. 3 , since the spin-up charge densities (regions 2 to 5 ) and the spin-down charge density (region 1 ) are mixed in the forskolin derivative A, it is determined to be a ferrimagnetic forskolin derivative (step S 13 ). On the other hand, for example, if the selected forskolin derivative is the forskolin derivative B, as shown in FIG. 5 , only the spin-up charge densities (regions 10 to 12 ) are present. Therefore, it is determined to be a ferromagnetic forskolin derivative (step S 14 ). It is also possible to obtain the magnetic strength based on the spin-charge density distribution. Incidentally, in the above-mentioned examples, side chains of a compound are portions indicated with R 6 , R 7 , R 13 in FIG. 1 and main chains are portions excluding the above-mentioned side chain portions from the structural formula in FIG. 1 .
As described above, according to the present drug design method and design system, the magnetism of a forskolin derivative having side chains modified with various atoms or molecules, and side chains optionally crosslinked can be determined. Moreover, by producing a forskolin derivative based on a molecular model determined to be magnetic, a magnetic drug can be manufactured. Therefore, it is possible to guide the drugs to the target sites in the body by use of magnetism of the drugs themselves without using supports (carriers) made from magnetic bodies as in the conventional cases. As a result, conventional problems such as difficulties in oral administration, the large size of carrier molecules in general, or technical problems in bond strength and affinity with the drug molecules can be resolved. Furthermore, it is possible to realize a drug delivery system which is easy to put into practical application.
In the above first embodiment, regarding both the forskolin derivatives A and B, the three-dimensional structure is forcibly altered so as to crosslink the oxygen atom bonded to C 9 and the carbon atom bonded to C 13 . However, the types of atoms to be crosslinked are not limited to the above examples; and other atoms may be selected to be crosslinked. Moreover, by not performing crosslinking, but by simply changing an atom or a molecule for modifying the side chain, whether the relevant derivative is magnetic or not may be determined.
Moreover, in the above first embodiment, forskolin is used as an organic compound for description. However, the type of organic compound to be used is not limited to this, and other organic compounds may be used. Hereunder is a description of, as another organic compound, a composition effective in treatments of male erectile dysfunction, more specifically, a composition inhibiting the activity of phosphodiesterase 5 (PDE 5), which hereinafter will be referred to as “PDE 5 inhibitor”. Drugs having this PDE 5 inhibitor as an active ingredient are used as remedies for male erectile dysfunction such as so-called Viagra®.
FIG. 7A is a diagram of a basic molecular structural model of PDE 5 inhibitor with a standard composition and FIG. 7B shows a three-dimensional molecular structure and spin-charge density distribution of the PDE 5 inhibitor with a standard composition that are obtained by a computer simulation in the abovementioned drug design method. On the other hand, FIG. SA is a diagram of a basic molecular structural model of a PDE 5 inhibitor derivative derived by subjecting the PDE 5 inhibitor with a standard composition to side chain modifications. FIG. 8B shows a three-dimensional molecular structure and spin-charge density distribution of the PDE 5 inhibitor derivative obtained by the abovementioned computer simulation. In FIG. 8B , the regions 20 to 23 show upward spin-charge densities, and the regions 24 to 26 show downward spin-charge densities. Therefore, the PDE 5 inhibitor derivative is a ferrimagnetic body where the upward spin states 20 ′ to 23 ′ and the downward spin states 24 ′ to 26 ′ coexist as shown in FIG. 8A .
That is, as shown in these FIGS. 7 and 8 , although the PDE 5 inhibitor with a standard composition is not magnetic, the PDE 5 inhibitor derivative which is generated by side chain modification is confirmed to be magnetic. Therefore, it has been found that as a result of using a therapeutic agent for male erectile dysfunction, which has such a magnetic PDE 5 inhibitor derivative as an active ingredient, pharmacological effects of the drug can be brought out specifically in the target site and the occurrence of side effects due to the combined use with the nitro preparations can be suppressed.
Second Embodiment
Next, a second embodiment is described using an inorganic compound, more specifically, cisplatin as an anticancer agent. Cisplatin is a metal complex (platinum complex) and classified as a platinum preparation among the anticancer agents.
FIG. 9 is a diagram of a basic molecular structural model of cisplatin with a standard composition. Using the computer simulation by the drug design method described in the first embodiment, this cisplatin with a standard composition is confirmed to be non-magnetic. On the other hand, FIG. 10A is a diagram of a basic molecular structural model of a cisplatin derivative (Cis-Pt-a3), which is derived by subjecting the cisplatin with a standard composition to side chain modifications. Additionally, FIG. 10B shows a three-dimensional molecular structure and spin-charge density distribution of the cisplatin derivative (Cis-Pt-a3) obtained by the abovementioned computer simulation.
In FIG. 10B , the regions 30 to 32 show upward spin-charge densities. Therefore, the cisplatin derivative (Cis-Pt-a3) is found to be a ferromagnetic body where the upward spin states 30 ′ to 32 ′ exist as show in FIG. 10A . That is, using the computer simulation by the present drug design method, the cisplatin derivative (Cis-Pt-a3) is confirmed to be magnetic. Therefore, by using an anticancer agent, which has such a magnetic cisplatin derivative (Cis-Pt-a3) as an active ingredient, pharmacological effects of the drug can be brought out specifically in the cancer tissues and the occurrence of side effects can be suppressed.
The stronger the magnetism of a drug, the more efficiently the drug can be guided to the target site, and thus, a greater increase in pharmacological effects and suppression of side effects can be expected. Accordingly, the present inventors carried out an analysis of magnetic strength for various cisplatin derivatives using the computer simulation by the present drug design method. The analytical results are described below. Since the magnetic strength is in a linear relationship with the spin-charge density, the spin-charge densities in various cisplatin derivatives are analyzed in the present embodiment.
Firstly, as a reference, particles having a total number of 101 atoms and which were approximately 8 Å on a side were cut out from a magnetite (Fe 3 O 4 ) crystal and were set as the molecular models, and after electronic states and structures were optimized by the above-mentioned computer simulation, the analysis of spin-charge densities was performed. Then, by adopting the spin-charge density of the abovementioned magnetite particles as the standard, the analysis of spin-charge densities for various cisplatin derivatives was similarly carried out. FIG. 16 shows operation screens displayed during processing corresponding to step 12 of the aforementioned computer simulation. FIG. 16 ( 1 ) shows the spin-charge density of the compared magnetite. ● indicates that the spin-charge density is positive; and ∘ indicates that the spin-charge density is negative. FIG. 16 ( 2 ) shows the calculated spin-charge density. The type of magnetism is ferrimagnetic (positive spin-charge density) and the magnetic strength is 10% as compared to magnetite.
Furthermore, in addition to the cisplatin derivatives, various derivatives where platinum (Pt) of the cisplatin derivatives was substituted by palladium (Pd), rhodium (Rh), iridium (Ir), gold (Au), nickel (Ni), silver (Ag), copper (Cu), or cobalt (Co) were similarly analyzed for their spin-charge densities. The derivatives generated by the substitution of platinum in the cisplatin derivatives with the abovementioned metal elements, as described above, are known to have effects in inhibiting the replication of DNA which is accompanied with the propagation of cancer cells, similarly to cisplatin or cisplatin derivatives.
FIG. 11 shows the analytical results of spin-charge densities of various cisplatin derivatives and of various derivatives where platinum (Pt) of the cisplatin derivatives was substituted by palladium (Pd), rhodium (Rh), iridium (Ir), gold (Au), nickel (Ni), silver (Ag), copper (Cu), or cobalt (Co), when the spin-charge density of the magnetite particles was standardized to “1”.
As shown in FIG. 11 , among the cisplatin derivatives, it was found that NK121 had approximately 60% of spin-charge density compared to that of the magnetite particles and is effective as a magnetic drug compared to other cisplatin derivatives. This cisplatin derivative NK121 is one which once managed to reach clinical development after a safety test. However, since the anticancer effect thereof was comparable to that of cisplatin, it was determined to have no merits surpassing cisplatin and the development thereof was suspended. Therefore, if this cisplatin derivative NK121 is taken and the guidance of the drug to the target site by means of a magnetic field is performed, drug effects would increase and side effects can also be suppressed to a large extent. FIG. 12 shows a diagram of a basic molecular structural model of the cisplatin derivative NK121. As shown in this diagram, the cisplatin derivative NK121 is a ferromagnetic body where the upward spin states 40 ′ to 42 ′ exist.
Moreover, the derivatives where platinum (Pt) of the cisplatin derivatives was substituted by palladium (Pd) were also confirmed to have spin-charge densities to some extent and thus, were magnetic bodies. In addition, among the derivatives where platinum (Pt) of the cisplatin derivatives was substituted by rhodium (Rh), Cis-Rh-a3 was found to have approximately 50% of spin-charge density compared to that of the magnetite particles and was effective as a magnetic drug. Further, the derivatives where platinum (Pt) of the cisplatin derivatives was substituted by iridium (Ir) were confirmed to have considerably small spin-charge densities and not many effects as magnetic drugs. Additionally, the derivatives where platinum (Pt) of the cisplatin derivatives was substituted by gold (Au) were also confirmed to have spin-charge densities to some extent and were magnetic bodies.
Moreover, the derivatives where platinum (Pt) of the cisplatin derivatives was substituted by nickel (Ni) generally had approximately 50% of spin-charge densities compared to those of the magnetite particles and were found to be effective as magnetic drugs. Additionally, the derivatives where platinum (Pt) of the cisplatin derivatives was substituted by silver (Ag) were also confirmed to have spin-charge densities to some extent and were magnetic bodies. In addition, the derivatives where platinum (Pt) of the cisplatin derivatives was substituted by copper (Cu) were also confirmed to have spin-charge densities to some extent and were magnetic bodies. Furthermore, it was found that the derivatives where platinum (Pt) of the cisplatin derivatives was substituted by cobalt (Co) had, among higher ones thereof, approximately 95% of spin-charge densities compared to those of the magnetite particles, and also, generally had considerably high spin-charge densities, and were highly effective as magnetic drugs.
As described so far, according to the drug design method in the present embodiment, not only with the drugs comprising organic compounds but also with those comprising inorganic compounds, it is possible to analyze whether they are magnetic or not from molecular models thereof. Moreover, by examining drugs with high magnetic strength (that is, with high drug effects) in advance, it will become possible to design effective drugs with a considerably high efficiency.
The above-described cisplatin derivatives and the derivatives where platinum of the cisplatin derivatives was substituted by other metal elements are cis geometric isomers. Such cis geometric isomers are used as anticancer agents since they have higher effects at inhibiting the replication of DNA which is accompanied with the propagation of cancer cells than those in trans geometric isomers. However, according to the drug design method in the present embodiment, targeted drugs can be analyzed whether they are magnetic or not, not only when they are cis geometric isomers of anticancer agents or the like, but also when they are the metal complexes composed of trans geometric isomers or when they are other inorganic compounds. Therefore, it is also possible to design magnetic drugs comprising the metal complexes composed of trans geometric isomers, or other inorganic compounds.
Next is a description of a guidance system for guiding the abovementioned magnetic drug to a target site. This guidance system may be any system as long as it generates a magnetic field, and various forms of systems can be considered. For example, application of magnetic resonance imaging (MRI) is considered, and the MRI system may be configured so that a magnetic field is irradiated to the human body and the magnetic field is controlled so as to guide the drug to the target site. Moreover, for example, a magnetic material such as a magnet may be adhered onto the skin surface of the target site. As a result, the drug that has reached the vicinity of the target site is guided to the target site, and stays specifically at the target site, causing no side effects to other normal cells. According to the above guidance system, it is possible to selectively and specifically guide a magnetic drug to the target site.
Furthermore, using the magnetism of the drugs administered in a body, it is also possible to examine the dynamics of the drugs in the body, for example, the amount of drugs accumulated in affected tissues such as cancer tissues. More specifically, using a magnetic drug as a tracer, the dynamics of the drug in the body are examined by tracing the magnetism generated from the drug with a magnetic detector. With such a magnetic detector, it is possible to examine the dynamics of drugs in the body such as the time taken for the drugs to reach the target sites after being administered in the body and thus, the present invention can not only contribute to research and development of drugs, but also determine an appropriate dose of an anticancer agent. Since there is a correlation between the accumulated amount (concentration) of a magnetic drug using the MRI and MRI images as described later, analysis of the MRI images makes it possible to find the accumulated state of a therapeutic drug in affected tissues and determine an appropriate dose.
Furthermore, functional diagnostic imaging can be performed by utilizing the magnetism and pharmacological action of the drug administered into a body. More specifically, there is a drug (such as forskolin) that has a high affinity for proteins developed in a large amount in highly malignant cancer tissues (for example, proteins called “P-glycoprotein”). The amount of forskolin accumulated in cancer tissues can be examined by making the forskolin magnetic and administering the magnetic forskolin to a cancer patient. If the accumulated amount in the cancer tissues is large, it is possible to diagnose the cancer of the patient as highly malignant; or if the accumulated amount is small, it is possible to diagnose the cancer of the patient as benign. The diagnosis of cancer malignancy grading can be made with only MRI images without taking conventional measures such as biopsy or surgery.
The same can be said for the case where affected tissues are not those of a cancer, but are those of diseases relating to receptors for neural mediators such as acetylcholine, serotonin, and dopamine in the brain. For example, the severity level of Alzheimer's dementia can be determined by examining, with MRI images of the patient's head, the dynamics of a magnetic drug which specifically binds with receptor proteins.
It is known that when the cisplatin with a standard composition shown in FIG. 9 is administered in the body, the cisplatin is hydrolyzed by the hydrolysis process represented by the reactions 1 to 3 shown in FIG. 13 , and finally generates the hydrolysis of cisplatin [Pt(OH 2 ) 2 (dien)] 2+ . As mentioned above, the cisplatin with a standard composition shown in FIG. 9 is not magnetic. However, the present inventors discovered that, based on the present drug design method, this hydrolysate of cisplatin [Pt(OH 2 ) 2 (dien)] 2+ is magnetic. FIG. 14 shows a three-dimensional molecular structure and spin-charge density distribution of the cisplatin hydrolysate [Pt(OH 2 ) 2 (dien)] 2+ . As shown in this diagram, since the cisplatin hydrolysate [Pt(OH 2 ) 2 (dien)] 2+ has regions 50 and 51 with upward spin-charge densities, it is found to be a ferromagnetic body.
Therefore, even with the cisplatin with a standard composition, since it is magnetic after being administered in the body, it can be guided to the target site by the abovementioned guidance system and it is also possible to examine the dynamics thereof in the body with a magnetic detector and find the amount of the drug accumulated in cancer tissues.
FIG. 17 is a block diagram illustrating the principles of MRI. When the aforementioned magnetic drug is administered to a human body through, for example, oral administration, injection, or fluid administration, the human body is exposed to a magnetic field. The human body is exposed to radio waves of a specified frequency emitted from a transmission coil 170 . The atomic nuclei of the administered drug molecules resonate with the radio waves and the atomic nuclei themselves then emit radio waves. A reception coil 172 receives such radio waves and synthesizes them into MR images. As a result, the location and of the drug in the human body can be visually detected.
In the tissues into which the drug has been absorbed, the atomic nuclei constituting the tissues and the atomic nuclei of the drug are in different conditions. Therefore, an MRI control unit 174 selects an appropriate frequency of radio waves to be emitted and analyzes an MR signal emitted by certain atomic nuclei. As a result, it is possible to differentiate a signal of the drug and a signal of the tissues and detect in which tissues the drug exists.
FIG. 18 is a perspective view of the entire MRI system. Reference numeral 180 represents an examination table on which a test subject is placed and moved within a cylindrical magnet gantry 182 . The magnet gantry is equipped with a magnet field generation device and a coil(s) for MR signal detection. The magnetic field strength of the magnet gantry is previously set to 0.2, 0.5, 1.0, or 1.5 teslas (unit). By moving the test subject within the magnetic field, the dynamics of the administered drug in the body can be controlled in accordance with the movement of the magnetic field.
Using the MRI as described above makes it possible to not only examine the dynamics of the magnetic compound in the body, but also guide the magnetic compound to a target position in the body. The magnetic compound can also be used as a contrast medium for the MRI.
Other methods besides the MRI can be adopted. A breast cancer will be explained in detail below. A breast cancer is located in breasts. If the horizontal length, the vertical length, and the depth are determined in terms of the three dimension, the site of cancer tissues of a breast cancer can be identified. The site of the breast cancer is determined in advance by, for example, the MR or CT.
Permanent magnets are tucked into an undergarment (brassiere) on the side where the cancer is located. After an anticancer agent is administered to a patient, she wears the undergarment equipped with the magnets. The anticancer agent is directly injected into the cancer tissues. For example, the anticancer agent is injected into an artery leading to the breasts or into the cancer tissues. Subsequently, the patient wears the brassiere equipped with the magnets in order to avoid diffusion of the anticancer agent from the cancer tissues to the entire body.
Moreover, the following method may also be employed. An anticancer agent is administered intravenously. The intravenously administered anticancer agent is supplied to the heart, and further passes from the aorta via the internal thoracic artery to the rami mammarii, and then finally to the breasts. The respective branches are then made subject to a magnetic field, thereby guiding the anticancer agent there. Specifically speaking, the magnetic field is applied toward the root of the internal thoracic artery where the aorta branches into the internal thoracic artery, so that the anticancer agent will be guided to flow from the aorta to the internal thoracic artery. Regarding the magnetic field strength, it was found as a result of cell culture examinations that if the distance is short, the anticancer agent can be guided at 1 tesla (the strength used by MR). Two teslas would be enough for organs close to the skin, like in the case of a breast cancer. The magnetic field strength of the MR is normally about 1.5 teslas. Regarding the measurement sensitivity, sufficient measurement sensitivity was achieved with the condition of T1 weighted images as a result of animal experiments.
Next, an example of administering a drug to an individual body and obtaining images with the MRI system will be explained. FIG. 19 shows an MRI image taken with the MRI system, wherein the MRI image of a 9-week-old female rat (ddy by Japan SIC) was taken after administration through subcutaneous injection of a solution in which a magnetic iron complex (Fe-salen) was dissolved in pyridine (concentration: 0.137 mol/litter). As compared to the MRI image before the administration of the iron complex pyridine solution, the contrast effect can be observed in gaps between the organs and along the abdominal lining in the MRI image after the administration. The region indicated with arrows shows the iron complex accumulated in gaps between small intestines. When the MRI images were taken, small magnets were pasted to the abdominal cavity of the rat. The magnet field strength was set to 1.5 teslas in the MRI analysis.
Furthermore, FIG. 20 shows that an MRI image is dependent on the concentration of a drug. A group of samples shown on the left side is obtained by diluting a pyridine concentrate solution with water (double distilled water (DDW)), while a group of samples shown on the right side is obtained by diluting a pyridine iron complex saturated solution with pyridine. By changing the concentration of the iron complex in pyridine to, for example, ½ or 1/16 of the aforementioned concentration of the solution containing only pyridine, the MRI can detect changes in the concentration through images. Subsequently, when rat L6 cells were in 30% confluent state, Fe complex powder was sprinkled over a culture medium as much as required to enable visual observation of the Fe complex powder when being drawn to magnets. 48 hours later, the condition of the culture medium was photographed.
FIG. 21 shows the state where a bar magnet is made to be in contact with a rectangular flask with the culture medium for the rat L6 cells. Next, FIG. 22 shows the calculation results of the number of cells by photographing the bottom face of the rectangular flask from its one end to the other end 48 hours later. Referring to FIG. 22 , “proximal to magnet” means within the projected area of the bottom of the rectangular flask in contact with the end face of the magnet, while “distal from magnet” means an area of the rectangular flask opposite the end face of the magnet. FIG. 22 shows that at the area proximal to the magnet, the iron complex is drawn to the magnet and the concentration of the iron complex increases accordingly, and the number of cells is extremely low, as compared to the area distal from the magnet, because of DNA inhibition effect of the iron complex. As a result, the magnetic drug and the system including the magnetic field generating means according to the present invention can concentrate the drug at the target affected part or tissues of an individual body.
Next, another example of a guidance system according to the present invention will be explained. In this guidance system, a pair of magnets 230 and 232 located opposite to each other in a direction of gravitational force is supported by a stand 234 and a clamp 235 , and a metal plate 236 is placed between the magnets as shown in FIG. 23 . A locally uniform and strong magnet field can be generated by placing the metal plate, particularly an iron plate, between the pair of magnets.
In this guidance system, electromagnets can be placed instead of the above-described magnets, so that the magnetic force to be generated can be made variable. Furthermore, a pair of magnetic force generating means may be designed to be movable in X, Y, and Z directions so that the magnetic force generating means can be moved to the target position of the individual body on the table.
The drug can be concentrated on the target tissues by placing the tissues of the individual body in this area of the magnetic field. The aforementioned metal complex (drug concentration: 5 mg/ml (15 mM)) was administered intravenously to a mouse (weight: approximately 30 g), the abdominal cavity of the mouse was opened, and the mouse was then placed on the iron plate so that its right kidney was positioned between the pair of magnets.
The magnets used were neodymium permanent magnets made by Shin-Etsu Chemical Co., Ltd. (product number: N50; residual magnetic flux density: 1.39-1.44 T). The magnetic field then applied to the right kidney was approximately 0.3 (T) and the magnetic field applied to the left kidney was approximately 1/10 of that for the right kidney. The magnetic field was applied to the mouse's right kidney; and 10 minutes later, the SNR of the right kidney as well as the left kidney and another kidney (control) to which no magnetic field was applied was measured in T1 mode and T2 mode, using the MRI system. As a result, it was confirmed as shown in FIG. 24 that a larger amount of the drug could be held in the tissues of the right kidney (RT), to which the magnetic field was applied, than in the left kidney (LT) or the control.
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It is intended to provide a drug delivery system which makes it possible to solve the existing technical problems and is easily usable in practice. A drug, which comprises an organic compound or an inorganic compound and has been magnetized by modifying a side chain and/or crosslinking side chains, is induced by a magnetic force into target tissues or an affected part.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention is in the field of detergent additive dispensers for use with a laundry appliance having a rotating spin basket.
2. Description of the Prior Art laundry appliances already known in the art are usually mounted at various positions allowing communication with the washing liquid at some point during the course of the wash cycle. Such dispensing devices are frequently mounted either on or in connection with the central agitator post, or along the rim of the basket holding the items to be wash.
Spin basket mountable dispensing devices such as shown in U.S. Pat. No. 3,268,120 rely on the centrifugal force generated by the rotation of the spin basket to transfer the liquid to be dispensed from a first compartment to a second compartment, said liquid then being gravitationally dispensed upon cessation of rotation. Such dispensers, however, are not constructed to accept inlet water from an inlet water source communicating with the interior of the spin basket. The nature of most liquids used in connection with laundry appliances is such that use over a period of time results in deposits of dried, unused liquid accumulating at various places in the devices. Such build-up generally occurs at portions of the device where the flow of liquid is somewhat constricted. If such deposits are not frequently removed by rinsing, accumulation of dried liquid may be such as to completely block the flow channel, resulting in complete failure of the device.
None of the liquid dispensing devices known in the art are constructed to receive water from the water inlet source of the laundry appliance during a post-dispense step of a wash cycle so that the device is rinsed as a part of every complete wash cycle, thereby preventing the build-up of deposits and obviating the deficiencies of the liquid dispensing devices known in the art which must be removed from the laundry appliance and rinsed manually at periodic intervals to prevent such build-up.
SUMMARY OF THE INVENTION
The present invention provides a laundry liquid dispenser which is attachable to the upper rim of a rotating spin basket in an automatic laundry appliance. In the preferred form of the present invention, the dispenser has a first compartment with an opening for filling which extends into the spin basket. Liquid poured into the first compartment will remain therein while the spin basket and dispenser are at rest, such as during the wash cycle of the laundry appliance. During a portion of the wash cycle the spin basket is rapidly rotated to remove water from the items to be washed. Such rotation imparts a centrifugal force which causes the liquid in the first compartment to flow into a second compartment in the dispenser communicating with the first compartment. The liquid is maintained in the second compartment as long as the spin basket is rotating, and flows gravitationally therefrom through an opening in the bottom of the second compartment when rotation ceases.
The filling opening of the first compartment extends a sufficient distance into the spin basket to receive inlet water from the water inlet source communicating with the wash basket of the laundry appliance. After the liquid to be dispensed has flowed into the wash basket, the subsequent activation of inlet water during the rinsing steps of the cycle washes out the dispenser so as to prevent build-up of incompletely dispensed, dried additive.
The first compartment of the dispenser is divided by a partition into two communicating portions, so that movement of the liquid is restricted and spillage from the portions will not occur should the basket move during the agitation portion of the cycle. The dispenser may be used to dispense detergent or rinse additive. Detergent, but not rinse additive, may be dispensed where the wash cycle consists of a rinse, spin, wash, spray rinse spin, spin, rinse and spray rinse spin because the detergent will thus be added to the wash portion of the cycle. Rinse additive may be dispensed where the wash cycle consists of wash, spin, rinse and spray rinse spin because the rinse additive will be added to the rinse portion of the cycle.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view, partly broken away, of a conventional type of automatic washing machine which is provided with the rinsable liquid additive dispenser of the present invention.
FIG. 2 is a perspective view of the rinsable liquid additive dispenser.
FIG. 3 is an enlarged frontal view of the liquid additive dispenser mounted in the spin basket of a laundry appliance.
FIG. 4 is a sectional view taken along the line IV--IV of FIG. 3.
FIG. 5 is an elevational plan view of the liquid dispensing device taken along line V-V of FIG. 3.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
An automatic washing machine is generally illustrated in FIG. 1 at 10 as comprising a tub 12 which has a perforate clothes container or spin basket 14 contained in the tub 12 and an agitator 16 vertically disposed within the spin basket 14 and mounted for oscillatory movement with respect thereto and for spinning movement with the basket during centrifugal extraction of water from the clothes within the basket 14. The tub 12, the spin basket 14, the agitator 16 and a drive mechanism 56 therefor are contained in a cabinet 18.
The cabinet 18 also has a top 34 having a hinged lid 36 which is opened to afford access to a clothes receiving opening 38 defined by a tub ring 40 extending about the tub and over a corresponding opening in the spin basket 14. The cabinet 18 also includes a pre-selectable sequential control means having a timer dial 42 connected to a timer-controller 44 which is mounted at the front of the cabinet 18. Suitable wiring 46 connects the timer 44 to a drive motor 48 and to other electrical components of the machine to control operation of the washing machine through a programmed sequence of a wash cycle. The wash cycle may include a wash portion, wherein a clothes load is agitated in a water and detergent solution, a spin portion where the basket 14 is rotated at high speed to centrifugally extract the wash solution from the load, a rinse portion wherein the load is agitated in a water solution with or without a rinse additive, and a spray rinse spin portion wherein the basket is rotated to centrifugally extract the water from the load while inlet water is sprayed on the load to further rinse the load. Other sequences are of course possible and may be used as hereinafter described. The timer dial 42 and the timer 44 may be mounted in any desired location and are shown in their present location for illustrative purposes only.
A pump 58 is provided for removing wash or rinse water from the tub 12 at the termination of a washing or rinsing operation and is suspended from a base plate 52. The pump is connected to drain the tub 12 through a drain hose 60. The motor 48, the drive mechanism 56 and the pump 58 may be mounted in any convenient manner inside the cabinet 18 and need not necessarily occupy the positions shown in FIG. 1.
The cabinet 18 also forms a mounting for a suitable water inlet valve 62 of conventional construction which controls the supply of water introduced into the tub 12 for a particular selected washing or rinsing operation. The water inlet valve provides selective fluid communication between an inlet hose 64 connected to a source of water under pressure and a conventional anti-siphoning device 68 which may be mounted on the tub ring 40.
As shown in FIGS. 1, 3 and 4 a rinsable laundry additive dispensing device 20 is shown hanging from a flange 15 at the top of the spin basket 14. The dispenser 20 is shown disposed beneath a portion 40a of the tub ring 40 which includes a water inlet opening 50 connected to a hose 67 extending from anti-siphon device 68.
The laundry additive dispenser is shown in an enlarged perspective view in FIG. 2. As best shown in FIG. 4, the dispenser 20 has a hanger 21 which snaps over the flange 15 on the spin basket 14 to provide sufficient friction between the flange and the hanger to hold the dispenser 20 substantially immovable with respect to the spin basket 14 during machine operation. Note, however, that the dispenser is manually movable circumferentially on the flange 15. This is accomplished by grasping the dispenser 20 and sliding it circumferentially on flange 15 of basket 14. The dispenser can thus be manually moved to any desired location for filling with a liquid additive and to insure that the dispenser is not positioned under inlet opening 50 after filling. The dispenser 20 has a back wall 27 which rests adjacent the perforated spin basket 14. An inclined lower portion 22 also rests against the spin basket 14 to provide further stability. A first compartment 23 is comprised of a front wall 24 which is upwardly inclined toward the interior of the spin basket 14 in which the dispenser 20 is mounted. A rear wall 29 is attached to the bottom of the front wall 24 at lower portion 29a with triangular side panels 25 attached between the back portion 29 and the front wall 24 to provide a fluid-holding compartment 23. The compartment is divided into two communicating portions shown in FIG. 5 as 72 and 73 by a dividing wall 31. The dividing wall 31 reduces the possibility of spillage caused by any movement of the basket during the agitate portion of the cycle because it acts as a baffle to reduce liquid flow across the compartment 23. Two triangular portions 26 are attached at the top of each of the side walls 25 to define a filling opening 28 in conjunction with the back wall 27 and the top of the front wall 24.
A second compartment 35 is defined by the back wall 27 and the rear wall 29 of the first compartment 23. A base 32 and lower portion 29a of the first compartment 23 define an opening 30 at the bottom of the second compartment 35.
As shown in FIG. 5, the entire dispenser 20 possesses a curved shape so as to rest adjacent the spin basket 14. The side wall 25 and the partition panel 31 may lie on radii of the spin basket 14, or the side walls 25 may be slanted inwardly at a more acute angle.
The liquid dispensing device 20 is shown positioned in FIGS. 3 and 4 in intercepting registry beneath water inlet port 50 of the laundry appliance 10. An interior portion 51 of the tub ring 40 is flanged downwardly from the inlet port 50. As shown in FIG. 4, water emerging from the inlet port 50 in thereby dispersed in a diverging spray by the outlet defined by the flange 51.
Operation of the liquid dispensing device 20 during a wash cycle of the laundry appliance 10 is demonstrated in FIG. 4. Liquid 70 to be dispensed is poured into the first compartment 23 of the device 20 via the opening 28 to a level represented at C. During the wash portion of the wash cycle, the spin basket and liquid dispensing device 20 mounted thereon remain relatively stationary with respect to the tub 12, and the liquid 70 in the first compartment 23 is therefore undisturbed. After the wash portion of the cycle, the spin basket 14 is rapidly rotated to extract water from the items being washed, and the centrifugal force generated by the rotation moves the liquid 70 from the level C in the direction of arrow D. When maximum angular velocity is attained, the liquid 70 will be held in a position 71 against the curved back wall 27 of the dispenser 20, generally defined by a line E. When the centrifugal force is removed when the rotation ceases at the end of the spin portion of the cycle, the liquid 70 will gravitationally flow through the opening 30 at the bottom of the second compartment 35 in the direction of arrow F and be dispensed into the interior of the basket 14.
After the liquid 70 has flowed from the dispensing device 20 and an agitation period has been completed, a spray rinse spin portion of the wash cycle is initiated. During this portion of the cycle, the spin basket will again rotate and once each revolution the opening 28 will pass beneath the area 40a of the tub ring 40 wherein the inlet port 50 is disposed. Rinse water will emerge from the inlet port 50 toward the interior of the basket 14 in the direction of arrows B. The first compartment 23 of the dispensing device 20 extends a sufficient distance into the basket 14 such that a portion of the inlet water will be captured in the compartment 23. The rinse water will pass through the dispenser 20 in the same manner as the laundry additive by being centrifugally forced into the second compartment 35 due to the spinning of basket 14 and will gravitationally flow through the opening 30 when rotation of basket ceases. The dispenser 20 is thereby rinsed clean after each use, preventing build-up of deposits of incompletely dispensed laundry additive which may remain in the dispenser 20.
It may be desirable to utilize the dispenser 20 with different types of laundry additives. The liquid in the liquid dispensing device 20 will be dispensed in the first spin portion and that should be prior to a spray rinse cycle to rinse out the device 20. Thus, detergent, but not rinse additive may be dispensed where the wash cycle consists of portions such as rinse, spin, wash, spray rinse spin, spin, rinse and spray rinse in that order. The detergent is dispensed after the first spin for use in the wash portion and the dispenser cleaned during the later spray rinses. A rinse additive may be dispensed where the cycle is wash, spin, rinse, and spray rinse spin in that order because the rinse additive will be dispensed into the rinse water and the dispenser washed out by the spray rinse spin.
Various modifications and changes may be apparent to those skilled in the art without departure from the spirit and scope of the present invention, and applicants intend to include within the patent warranted hereon all such changes and modifications as may reasonably and properly be included within the scope of our contribution to the art.
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A rinse or detergent additive dispenser for use in a laundry appliance hangs inside a spin basket and has a first compartment to hold and retain additive during a wash portion of a cycle, and a second compartment communicating with the first compartment which is filled by centrifugal force imparted to the additive in the first compartment during a spin portion of a wash cycle. An opening in the bottom of the second compartment allows gravitational draining of the additive therein when the centrifugal force is removed when rotation of the spin basket ceases, allowing the additive to be dispensed. The first compartment and the automaic washer water inlet are constructed and disposed in registry so that as the dispenser passes under the water inlet during the spray rinse spin of the cycle, the dispenser is rinsed clean.
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CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation application of U.S. Non-Provisional patent application Ser. No. 12/635,062, filed on Dec. 10, 2009 (docket no. 1269-0002-1), now U.S. patent Ser. No. ______, which claims the benefit of U.S. Provisional Patent Application No. 61/121,590, filed on Dec. 11, 2008 (docket no. 1269-0002), the contents of each of which are incorporated herein by reference in their entireties.
TECHNICAL FIELD
[0002] The present invention relates generally to joint systems for use in concrete and other building systems and, more particularly, to expansion joints for accommodating thermal and/or seismic movements in such systems.
BACKGROUND OF THE INVENTION
[0003] Concrete structures and other building systems often incorporate joints that accommodate movements due to thermal and/or seismic conditions. These joint systems may be positioned to extend through both interior and exterior surfaces (e.g., walls, floors, and roofs) of a building or other structure.
[0004] In the case of an exterior joint in an exterior wall, roof, or floor exposed to external environmental conditions, the expansion joint system should also, to some degree, resist the effects of the external environment conditions. As such, most external expansion joints systems are designed to resist the effects of such conditions (particularly water). In vertical joints, such conditions will likely be in the form of rain, snow, or ice that is driven by wind. In horizontal joints, the conditions will likely be in the form of rain, standing water, snow, ice, and in some circumstances all of these at the same time. Additionally, some horizontal systems may be subjected to pedestrian and/or vehicular traffic.
[0005] Many expansion joint products do not fully consider the irregular nature of building expansion joints. It is common for an expansion joint to have several transition areas along the length thereof. These may be walls, parapets, columns, or other obstructions. As such, the expansion joint product, in some fashion or other, follows the joint as it traverses these obstructions. In many products, this is a point of weakness, as the homogeneous nature of the product is interrupted. Methods of handling these transitions include stitching, gluing, and welding. In many situations, it is difficult or impossible to prefabricate these expansion joint transitions, as the exact details of the expansion joint and any transitions and/or dimensions may not be known at the time of manufacturing.
[0006] In cases of this type, job site modifications are frequently made to facilitate the function of the product with regard to the actual conditions encountered. Normally, one of two situations occurs. In the first, the product is modified to suit the actual expansion joint conditions. In the second, the manufacturer is made aware of issues pertaining to jobsite modifications, and requests to modify the product are presented to the manufacturer in an effort to better accommodate the expansion joint conditions. In the first situation, there is a chance that a person installing the product does not possess the adequate tools or knowledge of the product to modify it in a way such that the product still performs as designed or such that a transition that is commensurate with the performance expected thereof can be effectively carried out. This can lead to a premature failure at the point of modification, which may result in subsequent damage to the property. In the second case, product is oftentimes returned to the manufacturer for rework, or it is simply scrapped and re-manufactured. Both return to the manufacturer and scrapping and re-manufacture are costly, and both result in delays with regard to the building construction, which can in itself be extremely costly.
SUMMARY OF THE INVENTION
[0007] The present invention is directed to water resistant expansion joint systems for installation into building joints. In one aspect, the present invention resides in a system for use in vertical or horizontal configurations and is designed such that it can be used for either an inside or outside corner. The system comprises open celled foam having a water-based acrylic chemistry infused therein. A layer of an elastomer is disposed on the open celled foam and is tooled to define a profile to facilitate the compression of the expansion joint system when installed between coplanar substrates. The system is delivered to a job site in a pre-compressed state ready for installation into the building joint.
[0008] In another aspect, the present invention resides in a vertical expansion joint system comprising a first section of open celled foam extending in a horizontal plane and a second section of open celled foam extending in a vertical plane. An insert piece of open celled foam is located between the first and second sections, the insert piece being configured to transition the first section from the horizontal plane to the vertical plane of the second section. The foam is infused with a water-based acrylic chemistry. A layer of an elastomer is disposed on the foam to impart a substantially waterproof property thereto. The vertical expansion joint system is pre-compressed and is installable between horizontal coplanar substrates and vertical coplanar substrates. Although the vertical expansion joint system is described as having an angle of transition from horizontal to vertical, it should be understood that the transition of the angles is not limited to right angles as the vertical expansion joint system may be used to accommodate any angle.
[0009] In another aspect, the present invention resides in a horizontal expansion joint system, the system being pre-compressed and installable between horizontal coplanar substrates. The system comprises first and second sections of open celled foam extending in a horizontal plane, the sections being joined at a miter joint. The open celled foam is infused with a water-based acrylic chemistry. A layer of an elastomer is disposed on the foam, the elastomer imparting a substantially waterproof property to the foam. Although the horizontal expansion joint system is described as transitioning right angles in the horizontal plane, it should be understood that the transition of the angles is not limited to right angles as the system may be used to accommodate any angle and may also be used in planes that are not horizontal.
[0010] In any embodiment, the construction or assembly of the systems described herein is generally carried out off-site, but elements of the system may be trimmed to appropriate length on-site. By constructing or assembling the systems of the present invention in a factory setting, on-site operations typically carried out by an installer (who may not have the appropriate tools or training for complex installation procedures) can be minimized. Accordingly, the opportunity for an installer to effect a modification such that the product does not perform as designed or such that a transition does not meet performance expectations is also minimized.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 is a perspective view of a vertical expansion joint system of the present invention.
[0012] FIG. 2 is an end view of the vertical expansion joint system taken along line 2 - 2 of FIG. 1 .
[0013] FIG. 3 is an end view of the vertical expansion joint system installed between two substrates.
[0014] FIG. 4 is a perspective view of an assembly of foam laminations being prepared to produce the vertical expansion joint system of FIG. 1 .
[0015] FIG. 5 is a perspective view of the assembly of foam laminations being further prepared to produce the vertical expansion joint system of FIG. 1 .
[0016] FIG. 6 is a perspective view of four sections of the vertical expansion joint system used in a building structure.
[0017] FIG. 7 is a perspective view of a horizontal expansion joint system of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0018] The present invention provides a resilient water resistant expansion joint system able to accommodate thermal, seismic, and other building movements while maintaining water resistance characteristics. The present invention is especially suited for use in concrete buildings and other concrete structures including, but not limited to, parking garages, stadiums, tunnels, bridges, waste water treatment systems and plants, potable water treatment systems and plants, and the like.
[0019] Referring now to FIGS. 1-3 , one embodiment of the present invention is an expansion joint system oriented in a vertical plane and configured to transition corners at right angles. This system is designated generally by the reference number 10 and is hereinafter referred to as “vertical expansion joint system 10 .” It should be noted, however, that the vertical expansion joint system 10 is not limited to being configured at right angles, as the products and systems of the present invention can be configured to accommodate any desired angle. The vertical expansion joint system 10 comprises sections of open celled polyurethane foam 12 (hereinafter “foam 12 ”) that have been infused with a water-based acrylic chemistry. It should be understood, however, that although the present invention is described as comprising polyurethane foam, the open celled foam can be any other suitable type of foam.
[0020] As is shown in FIG. 2 , the foam 12 comprises individual laminations 14 of foam, one or more of which are infused with a suitable amount of the acrylic chemistry. It should be noted that the present invention is not so limited as other manners of constructing the foam 12 are also possible. For example, the foam 12 of the present invention is not limited to individual laminations 14 assembled to construct the laminate, as the foam 12 may comprise a solid block of non-laminated foam of fixed size depending upon the desired joint size, laminates comprising laminations oriented horizontally to adjacent laminations, or combinations of the foregoing.
[0021] Also as is shown in FIG. 3 , the vertical expansion joint system 10 is positionable between opposing substrates 18 (which may comprise concrete, glass, wood, stone, metal, or the like) to accommodate the movement thereof. In particular, opposing vertical surfaces of the foam 12 are retained between the edges of the substrates 18 . The compression of the foam 12 during the installation thereof between the substrates 18 enables the vertical expansion system 10 to be held in place.
[0022] In any embodiment, when individual laminations 14 are used, several laminations, the number depending on the expansion joint size (e.g., the width, which depends on the distance between opposing substrates 18 into which the vertical expansion system 10 is to be installed), are compiled and then compressed and held at such compression in a fixture. The fixture, referred to as a coating fixture, is at a width slightly greater than that which the expansion joint will experience at the greatest possible movement thereof.
[0023] In the fixture, the assembled infused laminations 14 are coated with a waterproof elastomer 20 . The elastomer 20 may comprise, for example, at least one polysulfide, silicone, acrylic, polyurethane, poly-epoxide, silyl-terminated polyether, combinations and formulations thereof, and the like. The preferred elastomer 20 for coating laminations 14 for a horizontal deck application where vehicular traffic is expected is PECORA 301 (available from Pecora Corporation, Harleysville, Pa.) or DOW 888 (available from Dow Corning Corporation, Midland, Mich.), both of which are traffic grade rated silicone pavement sealants. For vertical wall applications, the preferred elastomer 20 for coating the laminations 14 is DOW 790 (available from Dow Corning Corporation, Midland, Mich.), DOW 795 (also available from Dow Corning Corporation), or PECORA 890 (available from Pecora Corporation, Harleysville, Pa.). A primer may be used depending on the nature of the adhesive characteristics of the elastomer 20 .
[0024] During or after application of the elastomer 20 to the laminations 14 , the elastomer is tooled or otherwise configured to create a “bellows,” “bullet,” or other suitable profile such that the vertical expansion joint system 10 can be compressed in a uniform and aesthetic fashion while being maintained in a virtually tensionless environment. The elastomer 20 is then allowed to cure while being maintained in this position, securely bonding it to the infused foam lamination 14 .
[0025] Referring now to FIGS. 4 and 5 , when the elastomer 20 has cured in place, the infused foam lamination 14 is cut in a location at which a bend in the vertical expansion system 10 is desired to accommodate a corner. The cut, which is designated by the reference number 24 and as shown in FIG. 4 , is made from the outside of the desired location of the bend to the inside of the desired location of the bend using a saw or any other suitable device. The cut 24 is stopped such that a distance d is defined from the termination of the cut to the previously applied coating of the elastomer 20 on the inside of the desired location of the bend (e.g., approximately one half inch from the previously applied coating of elastomer 20 on the inside of the bend). Referring now to FIG. 5 , the lamination 14 is then bent to an appropriate angle A, thereby forming a gap G at the outside of the bend. Although a gap of 90 degrees is shown in FIG. 5 , the present invention is not limited in this regard as other angles are possible.
[0026] Still referring to FIG. 5 , a piece of infused foam lamination constructed in a manner similar to that described above is inserted into the gap G as an insert piece 30 and held in place by the application of a similar coating of elastomer 20 as described above. In the alternative, the insert piece 30 may be held in place using a suitable adhesive. Accordingly, the angle A around the corner is made continuous via the insertion of the insert piece 30 located between a section of the open celled foam extending in the horizontal plane and a section of the open celled foam extending in the vertical plane. Once the gap has been filled and the insert piece 30 is securely in position, the entire vertical expansion system 10 including the insert piece 30 is inserted into a similar coating fixture with the previously applied elastomer 20 coated side facing down and the uncoated side facing upwards. The uncoated side is now coated with the same (or different) elastomer 20 as was used on the opposite face. Again, the elastomer 20 is then allowed to cure in position. Furthermore, the insert piece 30 inserted into the gap is not limited to being a lamination 14 , as solid blocks or the like may be used.
[0027] After both sides have cured, the vertical expansion system 10 as the final uninstalled product is removed from the coating fixture and packaged for shipment. In the packaging operation the vertical expansion system 10 is compressed using a hydraulic or mechanical press (or the like) to a size below the nominal size of the expansion joint at the job site. The vertical expansion system 10 is held at this size using a heat shrinkable poly film. The present invention is not limited in this regard, however, as other devices (ties or the like) may be used to hold the vertical expansion system 10 to the desired size.
[0028] Referring now to FIG. 6 , portions of the vertical expansion system 10 positioned to articulate right angle bends are shown as they would be positioned in a concrete expansion joint located in a tunnel, archway, or similar structure. Each portion defines a foam laminate that is positioned in a corner of the joint. As is shown, the vertical expansion joint system 10 is installed between horizontal coplanar substrates 18 a and vertical coplanar substrates 18 b.
[0029] Referring now to FIG. 7 , an alternate embodiment of the invention is shown. In this embodiment, the infused foam, the elastomer coating on the top surface, and the elastomer coating on the bottom surface are similar to the first embodiment. However, in FIG. 7 , the expansion joint system designated generally by the reference number 110 is oriented in the horizontal plane rather than vertical plane and is hereinafter referred to as “horizontal expansion system 110 .” As with the vertical expansion system 10 described above, the horizontal expansion system 110 may be configured to transition right angles. The horizontal expansion system 110 is not limited to being configured to transition right angles, however, as it can be configured to accommodate any desired angle.
[0030] In the horizontal expansion system 110 , the infused foam lamination is constructed in a similar fashion to that of the vertical expansion system 10 , namely, by constructing a foam 112 assembled from individual laminations 114 of foam material, one or more of which is infused with an acrylic chemistry. Although the horizontal expansion system 110 is described as being fabricated from individual laminations 114 , the present invention is not so limited, and other manners of constructing the foam 112 are possible (e.g., solid blocks of foam material).
[0031] In fabricating the horizontal expansion system 110 , two pieces of the foam 112 are mitered at appropriate angles B (45 degrees is shown in FIG. 7 , although other angles are possible). An elastomer, or other suitable adhesive, is applied to the mitered faces of the infused foam laminations. The individual laminations are then pushed together and held in place in a coating fixture at a width slightly greater than the largest joint movement anticipated. At this width the top is coated with an elastomer 20 and cured. Following this, the foam 112 is inverted and then the opposite side is likewise coated.
[0032] After both coatings of elastomer 20 have cured, the horizontal expansion system 110 is removed from the coating fixture and packaged for shipment. In the packaging operation, the horizontal expansion system 110 is compressed using a hydraulic or mechanical press (or the like) to a size below the nominal size of the expansion joint at the job site. The product is held at this size using a heat shrinkable poly film (or any other suitable device).
[0033] In the horizontal expansion system 110 , the installation thereof is accomplished by adhering the foam 112 to a substrate (e.g., concrete, glass, wood, stone, metal, or the like) using an adhesive such as epoxy. The epoxy or other adhesive is applied to the faces of the horizontal expansion system 110 prior to removing the horizontal expansion system from the packaging restraints thereof. Once the packaging has been removed, the horizontal expansion system 110 will begin to expand, and the horizontal expansion system is inserted into the joint in the desired orientation. Once the horizontal expansion system 110 has expanded to suit the expansion joint, it will become locked in by the combination of the foam back pressure and the adhesive.
[0034] In any system of the present invention, but particularly with regard to the vertical expansion system 10 , an adhesive may be pre-applied to the foam lamination. In this case, for installation, the foam lamination is removed from the packaging and simply inserted into the expansion joint where it is allowed to expand to meet the concrete (or other) substrate. Once this is done, the adhesive in combination with the back pressure of the foam will hold the foam in position.
[0035] The vertical expansion system 10 is generally used where there are vertical plane transitions in the expansion joint. For example, vertical plane transitions can occur where an expansion joint traverses a parking deck and then meets a sidewalk followed by a parapet wall. The expansion joint cuts through both the sidewalk and the parapet wall. In situations of this type, the vertical expansion system 10 also transitions from the parking deck (horizontally) to the curb (vertical), to the sidewalk (horizontal), and then from the sidewalk to the parapet (vertical) and in most cases across the parapet wall (horizontal) and down the other side of the parapet wall (vertical). Prior to the present invention, this would result in an installer having to fabricate most or all of these transitions on site using straight pieces. This process was difficult, time consuming, and error prone, and often resulted in waste and sometimes in sub-standard transitions.
[0036] In one example of installing the vertical expansion system 10 in a structure having a sidewalk and a parapet, the installer uses several individual sections, each section being configured to transition an angle. The installer uses the straight run of expansion joint product, stopping within about 12 inches of the transition, then installs one section of the vertical expansion system 10 with legs measuring about 12 inches by about 6 inches. If desired, the installer trims the legs of the vertical expansion system 10 to accommodate the straight run and the height of the sidewalk. Standard product is then installed across the sidewalk, stopping short of the transition to the parapet wall. Here another section of the vertical expansion system 10 is installed, which will take the product up the wall. Two further sections of the vertical expansion system 10 are used at the top inside and top outside corners of the parapet wall. The sections of the vertical expansion system 10 are adhered to each other and to the straight run expansion joint product in a similar fashion as the straight run product is adhered to itself. In this manner, the vertical expansion system 10 can be easily installed if the installer has been trained to install the standard straight run product. It should be noted, however, that the present invention is not limited to the installation of product in any particular sequence as the pieces can be installed in any suitable and/or desired order.
[0037] In one example of installing the horizontal expansion system 110 , the system is installed where there are horizontal plane transitions in the expansion joint. This can happen when the expansion joint encounters obstructions such as supporting columns or walls. The horizontal expansion system 110 is configured to accommodate such obstructions. Prior to the present invention, the installer would have had to create field transitions to follow the expansion joint.
[0038] To extend the horizontal expansion system 110 around a typical support column, the installer uses four sections of the horizontal expansion system. A straight run of expansion joint product is installed and stopped approximately 12 inches short of the horizontal transition. The first section of the horizontal expansion system 110 is then installed to change directions, trimming as desired for the specific situation. Three additional sections of horizontal expansion system 110 are then joined, inserting straight run pieces as desired, such that the horizontal expansion system 110 extends around the column continues the straight run expansion joint on the opposite side. As with the vertical expansion system 10 , the sections may be installed in any sequence that is desired.
[0039] The present invention is not limited to products configured at right angles, as any desired angle can be used for either a horizontal or vertical configuration. Also, the present invention is not limited to foam laminates, as solid foam blocks and the like may alternatively or additionally be used.
[0040] Although this invention has been shown and described with respect to the detailed embodiments thereof, it will be understood by those of skill 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, 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 embodiments disclosed in the above detailed description, but that the invention will include all embodiments falling within the scope of the appended claims.
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A water resistant expansion joint system for installation into a building joint in vertical and horizontal configurations is designed such that it can be used for either an inside or outside corner. According to an aspect, the system comprises open celled foam having a water-based acrylic chemistry infused therein. A layer of an elastomer is disposed on the open celled foam and is tooled to define a profile to facilitate the compression of the expansion joint system when installed between coplanar substrates. The system is delivered to a job site in a pre-compressed state ready for installation into the building joint.
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This application claims the benefit of the U.S. provisional application No. 60/070,482, filed Jan. 5, 1998.
BACKGROUND OF THE INVENTION
Hunting is a popular activity and is one that is as old as this country itself. Hunting is regulated by the various states and separated into seasons. Every state has a hunting season which is limited to bow hunting only. Hunters which engage in this type of hunting go into the woods with their equipment. They either carry their equipment or put it on to an all-terrain vehicle (ATV). It is common for a hunter to pick a spot in the woods and wait for game. Often, the hunter chooses to climb into a tree and wait in a tree stand. There is a need for a convenient way for the hunter to carry equipment into the woods to the spot that he chooses.
Various devices are available which hunters can use in the woods to carry a bow. U.S. Pat. No. 5,482,241 to Oglesby discloses a U-shaped bow support for attaching a bow to a tree. The bow support cannot be carried on the hunter's back or attached to an ATV. Osterholm, U.S. Pat. No. 3,465,928, discloses a quiver that can have a bow attached to it. The quiver does not have the capability to be attached to an ATV. U.S. Pat. No. 5,106,044 (Regard, III et al.), and U.S. Pat. No. 4,474,296 (Hartman) disclose stands for bows that are attached to the bow by screws. These stands are not used to carry the bow on a hunter's back or an ATV.
It is an object of this invention to provide a light-weight comfortable bow carrier that a hunter can carry.
It is also an object of the invention to have a bow carrier that is easily attached and detached from the bow.
It is a further object of the invention to have a bow carrier that is easy to manufacture and use.
SUMMARY OF THE INVENTION
The invention relates to a device that will hold a bow and can be carried on the hunter's back or can be mounted to the rack of an ATV. The device is easily attached to the rack of an ATV or carried by the hunter. It allows the hunter to have his hands free in order to engage in other activities.
The invention uses a support plate that has shoulder and waist straps attached to its front. These straps allow the user to carry the bow holder. The support plate may also have brackets connected to it which allow the bow holder to be secured to the rack of an ATV.
A bow carrier plate is attached to the back of the support plate. The bow carrier plate releasably retains a bow holder which is attached to the bow. The bow holder is a U-shaped member which has one leg screwed to the bow and the other leg retained by the bow carrier plate. The bow holder is quickly and easily separated from the bow carrier plate.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 depicts the bow holder;
FIG. 2 shows the support plate with the bow carrier plate attached;
FIG. 3 is a top view of the support plate and bow carrier plate where the shoulder and waist straps are visible;
FIG. 4 is a front view of the support plate with the shoulder and waist straps clearly visible;
FIG. 5 depicts how the bow holder is attached to a bow;
FIG. 6 shows the complete assembly of the support plate bow holder and bow;
FIG. 7 shows the bow holder and support plate on a user;
FIG. 8 is a top view of the support plate mounted to the rack of an ATV; and
FIG. 9 is a side view of the support plate attached to the rack of an ATV.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows the bow holder 10. The bow holder 10 is a generally "U" shaped piece having a first leg 12, a second leg 14, connected by a central portion 16. The legs are 2 inches high and the central portion is 41/4 inches long. The holder is 11/2 inches wide. The bow holder is preferably made of aluminum.
Turning to FIG. 2, a support plate 20 is shown with a bow carrier plate 30 attached thereto. The support plate is 12 inches long, 61/2 inches wide and 1/16 inch thick. The bow carrier plate is 21/4 inches long, and 21/4 inches wide and 1/16 inch thick. The bow carrier plate has a safety strap 40. The safety strap 40 is connected on one end by a screw 42 and on the other by a snap 44. The strap can also be attached to opposite sides of the support plate. A top of the support plate 20 has an aperture 28. A top view of the support plate and bow carrier plate can be seen in FIG. 3. From this view you can see that the support plate 20 is made of a layer of aluminum 22. The front of the support plate has a foam layer 24 which is 1/4 inch thick. The back of the support plate may be covered with a layer of camouflage fabric 26. Also seen in this view are the pair of shoulder straps 50 which connect to the waist strap 60. Clearly seen in this view is that the bow carrier plate 30 consists of two ends 32 connected to the support plate 20 with a center piece 34 which is spaced from the support plate 20. To connect the bow holder 10 to the support plate 20, the first leg 12 of the bow holder 10 fits between the space created between the center portion of the bow carrier plate 34 and the support plate 20. The first leg 12 is inserted downward into the space. The safety strap 40 extends over the top of the central portion and prevents the bow holder from inadvertently coming out by preventing its upward movement.
FIG. 4 shows the front view of support plate 20. As can be seen, the shoulder straps 50 have top ends which connect to the top edge of the support plate 20 and bottom ends which connect to the waist strap 60. The shoulder straps are made out of 1 inch nylon, and are adjustable. The waist strap 60 connects to itself in the middle by hook and loop fasteners 65. The support plate can be connected to a tree by fastening an eye-bolt 5 through the aperture 28 located at the top of the support plate 20.
FIG. 5 depicts how the bow holder 10 is connected to a bow 100. A conventional screw 11, can be used to pass through the aperture 18 in the second leg 14 of the bow holder. The screw passes through the aperture 18 and into the bow 100. The bow can be used with the bow holder still attached since it does not interfere with the operation of the bow when screwed to it.
Turning now to FIG. 6, the complete assembly of the support plate 20, the bow carrier plate 30, the bow holder 10, and the bow 100 can be seen. As will be noticed, the legs of the bow holder extend downward from the central portion 16 of the bow holder.
FIG. 7 shows a user wearing the bow holder. As can be seen, the shoulder straps allow the user's hands to be free and enable him to climb a tree in order to reach a tree stand, for instance.
FIG. 8 shows a top view of the bow carrier attached to the rack 80 of the ATV. This is achieved by using J members 70 that are attached to the support plate by means of bolts 75. One of the J members is attached through a bolt which passes through the first aperture 28. The other J member attaches through a bolt which passes through a second aperture 29, located at the bottom of the support plate 20.
FIG. 9 shows a side view of the bow carrier as it is attached to the rack 80 of the ATV. As can be seen, J members extend around the bars of the rack in order to securely maintain the bow carrier in its position.
Although an exemplary embodiment of the invention has been shown and described, it is appreciated that a number of changes, modifications or alterations may be made to the invention without departing from the spirit or scope of the invention.
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A carrier for a bow can be carried by a user as a backpack or attached to an all-terrain vehicle (ATV). The carrier facilitates the transportation of the bow to any desired location. The bow is easily attached and detached from the carrier for its ease in use.
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RELATED APPLICATION
[0001] This application claims priority to U.S. Provisional Application Ser. No. 61/261,369, filed Nov. 15, 2009, the disclosure of which is incorporated herein by reference.
BACKGROUND
[0002] The present disclosure relates to an implantable drug delivery system for the treatment of erectile dysfunction.
[0003] Erectile dysfunction (“ED”), sometimes called impotence, is the repeated inability to achieve or maintain an erection firm enough for sexual intercourse. The word impotence may also be used to describe other problems that interfere with sexual intercourse and reproduction, such as lack of sexual desire and problems with ejaculation or orgasm. ED can be a total inability to achieve erection, an inconsistent ability to do so, or a tendency to sustain only brief erections. In older men, ED usually has a physical cause, such as disease, injury, or side effects of drugs. Any disorder that causes injury to the nerves or impairs blood flow in the penis has the potential to cause ED. ED is treatable at any age, and awareness of this fact has been growing.
[0004] The penis contains two chambers called the corpora cavernosa, which run the length of the organ. A spongy tissue fills the chambers. The corpora cavernosa are surrounded by a membrane, called the tunica albuginea. The spongy tissue contains smooth muscles, fibrous tissues, spaces, veins, and arteries. The urethra, which is the channel for urine and ejaculate, runs along the underside of the corpora cavernosa and is surrounded by the corpus spongiosum. Erection begins with sensory or mental stimulation, or both. Impulses from the brain and local nerves cause the muscles of the corpora cavernosa to relax, allowing blood to flow in and fill the spaces. The blood creates pressure in the corpora cavernosa, making the penis expand. The tunica albuginea helps trap the blood in the corpora cavernosa, thereby sustaining erection. When muscles in the penis contract to stop the inflow of blood and open outflow channels, erection is reversed.
[0005] Current drugs for treating ED can be taken orally, injected directly into the penis, or inserted into the urethra at the tip of the penis. In 1998 the Food and Drug Administration approved sildenafil citrate (Viagra®, Pfizer, Inc.), the first pill to treat ED. Since that time, vardenafil HCl (Levitra®, Bayer Healthcare Pharmaceuticals, Inc.) and tadalafil (Cialis®, Eli Lilly & Co.) have also been approved. Additional oral medicines are being tested for safety and effectiveness. These drugs work by affecting certain parts of the signal pathway involved with penile smooth muscle relaxation, thus forcing smooth muscle relaxation and increasing the likelihood of achieving an erection.
[0006] Sildenafil citrate, vardenafil HCl, and tadalafil all belong to a class of drugs called phosphodiesterase (PDE) inhibitors. Taken an hour before sexual activity, these drugs enhance the effects of nitric oxide, a chemical that relaxes smooth muscles in the penis during sexual stimulation and allows increased blood flow. While oral medicines improve the response to sexual stimulation, they do not trigger an automatic erection, as injections do. Men who take nitrate-based drugs such as nitroglycerin for heart problems should not use PDEs because the combination can cause a sudden drop in blood pressure. Furthermore, taking a PDE inhibitor and an alpha-blocker, used to treat prostate enlargement or high blood pressure, at the same time can cause a sudden drop in blood pressure. And while these drugs are often effective in triggering the onset of an erection, they do not provide an immediate response to sexual stimulation. Additionally, drugs that are ingested orally require a total dose much larger than the minimal amount needed to stimulate the target site, resulting in side effects such as headache, facial flushing, upset stomach and sudden loss of vision. By utilizing a local drug delivery system, higher concentrations could be achieved at the target site even with the use of smaller dosages.
[0007] Oral testosterone can reduce ED in some men with low levels of natural testosterone, but it is often ineffective and may cause liver damage. Patients also have claimed that other oral drugs—including yohimbine hydrochloride, dopamine and serotonin agonists, and trazodone—are effective, but the results of scientific studies to substantiate these claims have been inconsistent.
[0008] Many men may achieve stronger erections by injecting drugs into the penis, causing it to become engorged with blood. Drugs such as prostaglandin E1, papaverine HCl, phentolamine, and alprostadil (Caverject®, Pfizer, Inc.) have been used for this purpose. For example, alprostadil induces erection by relaxation of trabecular smooth muscle and by dilation of cavernosal arteries. This leads to expansion of lacunar spaces and entrapment of blood by compressing the venules against the tunica albuginea, a process referred to as the corporal veno-occlusive mechanism. A major drawback of these therapies is that a patient must inject these drugs directly into the penis immediately prior to sexual intercourse, in addition, repeated administration may result in scarring.
[0009] A system for inserting a pellet of alprostadil into the urethra is marketed as Muse® (Vivus, Inc.). The system uses a pre-filled applicator to deliver the pellet about an inch deep into the urethra. An erection will begin within 8 to 10 minutes and may last 30 to 60 minutes. Common side effects are aching in the penis, testicles, and area between the penis and rectum; warmth or burning sensation in the urethra; redness from increased blood flow to the penis; and minor urethral bleeding or spotting. Like the injection therapies, a major drawback is that the application of the pellet must take place immediately prior to sexual intercourse.
[0010] External mechanical vacuum devices may be used to cause an erection by creating a partial vacuum, drawing blood into the penis, engorging and expanding it. These devices are typically only marginally effective and their use can cause embarrassment to the patient.
[0011] Surgery is sometimes employed as a treatment for ED, and usually has one of three goals: to implant a prostheses; to reconstruct arteries to increase flow of blood to the penis; or to block off veins that allow blood to leak from the penile tissues.
[0012] Mechanical prosthetic implants can simulate an erection in many men with ED. Several designs are currently employed, including one design that uses balloon-like chambers implanted within the penis, a small fluid reservoir implanted within the body and a manual pump mechanism implanted in the scrotum, which drives fluid from the reservoir to the chambers, thereby simulating an erection. Malleable implants usually consist of paired rods, which are inserted surgically into the corpora cavernosa. The user manually adjusts the position of the penis and, therefore, the rods. Adjustment does not affect the width or length of the penis. Drawbacks of implants include mechanical breakdown and infection, the need for fairly invasive surgery, damage to previously-intact penile tissue, and the fact that the erection achieved is not physiologically natural, i.e., not caused by blood pressure and blood volume changes within the penile tissues, resulting in a hindered sexual experience.
[0013] Surgery to repair arteries can reduce ED caused by obstructions that block the flow of blood. The best candidates for such surgery are young men presenting with discrete blockage of an artery, usually due to an injury to the crotch or fracture of the pelvis. The procedure is almost never successful in older men with widespread blockage. Surgery to veins that allow blood to leave the penis usually involves an opposite procedure—intentional blockage. Blocking off veins (ligation) can reduce the leakage of blood that diminishes the rigidity of the penis during erection. However, experts have raised questions about the long-term effectiveness of this procedure, and it is rarely performed.
[0014] Each of these methods treat ED to varying degrees, but each has their drawbacks such as systemic side effects, poor response times, cumbersome or painful delivery mechanisms, need for traumatic surgery and physiologically unnatural results. In addition, many of these methods are unable to achieve a physiologically natural erection and all require at least some amount of, and sometimes significant, pre-intercourse intervention.
SUMMARY
[0015] Recognition of a need for an improved form of therapy for ED led to the development of the low-power implantable drug delivery system described herein. The device uses a passively pressurized drug reservoir, the flow from which is modulated by ultra-low power microfluidic valves under direct or indirect control of the patient. The system provides for the delivery of a precise dosage of an erection-inducing pharmaceutical agent directly to the target tissue.
[0016] The low power consumption of the described device is achieved, in part, by the use of a passively-pressurized propellant chamber within the drug infusion pump portion of the device as the primary driving force for fluid flow. Such implantable constant-flow infusion pumps are well-known in the art (see, e.g., U.S. Pat. No. 5,643,207), and typically rely on a liquid/vapor equilibrium at physiologic temperature to maintain a constant pressure on the drug, which is housed in a compartment separate from, but adjacent to, the propellant chamber. The prior art teaches that, by selecting an appropriately-sized capillary tube to restrict fluid flow of the drug, a chosen constant flow rate can be maintained over long periods of time, often measured in months or years. Using passive pressurization to drive fluid from the drug reservoir requires no battery power, making it ideal for long-term therapeutic use in an implanted device, but conventional devices according to the prior art designs are not able to administer a discrete bolus of therapeutic upon command.
[0017] The present invention incorporates the use of microfluidic control valves, allowing for an ultra-low-power implantable device that can maintain therapeutic effectiveness over the course of many years, and many discrete drug bolus administrations. The incorporation of microfluidic control valves and a microcontroller allows for the use of what would otherwise be a constant-flow pump in an application requiring discrete and precise dosages at varying time intervals. In addition, microfluidic valves allow for more precise fluid flow regulation, and therefore, dosages.
[0018] The system described also incorporates a control module that allows both patient control over dosing, as well as prevention of accidental dosage administration, avoiding overdose. Implementation of patient control input may be accomplished through the use of implanted subcutaneous buttons, implanted subcutaneous RFID tags, an implanted neural signaling interface, RF triggers or any combination of these or similar input mechanisms. For a neural signaling interface, neural signals may be registered via microelectrodes in electrical communication with the spinal cord, brain, spinal nerves, cauda equina, or peripheral nervous system. Such signals can then be processed by a microcontroller and, under certain conditions, be used to trigger release of the therapeutic. Neural signals may thus be used, either alone or in combination with other control mechanisms, to achieve an essentially natural physiologic response to sensory or mental stimulation.
[0019] While there have been prior attempts to devise an implantable erection assist apparatus, see, e.g., U.S. Pat. No. 5,823,991 to Shim, such devices suffered from high power requirements because such devices taught actively pumping the therapeutic, distinctly limiting the useful life of the implanted device. In addition, such devices did not provide for a seamless, completely implanted user-interface control mechanism. The present invention overcomes these shortcomings.
[0020] The device and methods described herein result in increased treatment effectiveness, smaller effective dosages and reduced side effects as compared to the prior art. By delivering vasodilating compounds directly to the corpus cavernosum, without requiring systemic ingestion or local injection of active compounds, and especially when under neural control, the described device and method results in an essentially physiologically natural response to stimulation.
[0021] These general and specific elements can be implemented in a variety of combinations as apparatuses, methods, and systems. The details of one or more implementations are set forth in the accompanying drawings and the description below. Further features, aspects, and advantages will become apparent from the description, the drawings, and the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] FIG. 1 depicts a housing with an integrated pump and control mechanisms according to one embodiment of the invention.
[0023] FIG. 2 depicts one potential placement of the device housing within a patient, with catheters placed to deliver the selected drug.
[0024] FIG. 3 presents a cutaway view of a constant flow infusion pump of a type that may be employed in the invention.
[0025] FIG. 4 depicts a frontal view of one embodiment of the device.
[0026] FIG. 5 depicts a side view of one embodiment of the device.
[0027] FIG. 6 represents one possible configuration of microcontroller logic based on user input.
[0028] FIG. 7 is a block diagram depicting the nervous system control that leads to stimulation or inhibition of erection.
[0029] FIG. 8 is a block diagram depicting a method for microcontroller control of drug release based on exemplary neural threshold stimulation and duration values.
[0030] FIG. 9 is a block diagram depicting microcontroller-mediated opening of microfluidic valves in response to an appropriate signal from a user input mechanism in conjunction with neural stimulation.
[0031] Like reference symbols indicate like elements throughout the specification and drawings.
DETAILED DESCRIPTION
[0032] The overall system described herein comprises a passively pressurized drug infusion pump, microfluidic valves, catheters, a microcontroller, patient input mechanisms and a power source. In a main embodiment, the system comprises one or more drug fluid reservoirs to store a pharmaceutical agent effective for treating ED; one or more passively-pressurized chambers in pressure communication with the drug fluid reservoir(s); one or more catheters to transport the pharmaceutical agent to the penis, more specifically, to the corpora cavernosa on one or both sides of the penis; one or more low-power microfluidic valves for occluding flow of the pharmaceutical agent; a patient input mechanism; a microcontroller unit for (i) interpreting input from the patient input mechanism, (ii) controlling the microfluidic valves, thereby triggering the release of the dosage, (iii) performing any necessary computational functions, and (iv) accepting programming instructions from a user; and a power source. The fluid reservoirs, pressurized chambers, microcontroller, and power source may be housed within a single structure 100 , as depicted in FIG. 1 . FIG. 1 also depicts a drug reservoir fill port 110 , a drug administration catheter 120 , an implantable patient input mechanism 130 , microfluidic valves 140 , and housing attachment points 150 .
[0033] In one embodiment, the device housing 100 is designed to fit congruently within the contours of a patient's pubic bone. In another embodiment the device housing 100 is implanted in the subcutaneous tissue of the abdomen, implantation is preferably done via a minimally invasive procedure. FIG. 2 depicts a potential arrangement of the device housing 100 , catheters 120 and patient input mechanism 130 within a patient. As patients will have differing pubic bone structures, in one embodiment, the contours on the posterior surface of the device housing 100 may be selected from different undersurfaces that can be attached to the housing prior to surgical implantation of the device. In a typical embodiment, the outer shell of the housing 100 , and any attached undersurface, will be constructed of titanium or a titanium alloy such as niobium and tantalum. Although the device housing 100 is not limited to titanium and its alloys, such materials are ideal for, and conventionally employed as exterior surfaces for, hermetically sealed implantable devices. In one embodiment, the device housing 100 will have a curvaceous surface to reduce the device profile, ideally with virtually no sharp edges.
[0034] In accordance with one aspect of the invention, a constant-flow, passively-pressurized drug infusion pump of essentially standard construction may be employed within the device housing to provide the driving force for discharge of the therapeutic drug to the intended administration site. In one embodiment, as shown in FIG. 3 , the infusion pump will provide a drug reservoir containing the selected therapeutic in solution, wherein the reservoir is in pressure communication with a passively-pressurized propellant chamber. In accordance with known practice, a fluorocarbon gas may be used to create the specific pressure necessary for expelling solution from the drug reservoir; trichlorofluoromethane (Freon) is a typical choice that vaporizes at physiologic temperatures. FIG. 3 depicts a typical constant-flow, passively-pressurized drug infusion pump of the type well-known in the art, e.g., as described in U.S. Pat. Nos. 3,731,681 and 4,221,219.
[0035] In one embodiment, the infusion pump portion of the disclosed device is composed of the following components: a collapsible drug reservoir of a selected initial volume 330 ; propellant (pump drive) chamber 320 ; reservoir fill port incorporating a self-sealing septum 300 ; a biocompatible housing 370 ; capillary tubing 380 and housing attachment points for securing the housing via fixation devices and/or sutures 360 . A pump in accordance with this general design has a constant flow rate that is selected by design choices regarding the volume of the drug reservoir 330 , size and length of capillary tubing 380 and internal pressure in propellant chamber 320 .
[0036] In accordance with the embodiment depicted in FIG. 3 , the propellant chamber 320 , located behind the drug reservoir 330 , is filled with a two-phase fluid that has a significant vapor pressure at body temperature and places a constant pressure on the drug reservoir 330 to force the drug out through the catheter port 310 to the site of delivery via a capillary (not shown). As the fluid vaporizes at body temperature, it compresses a bellows 340 separating the drug reservoir 330 from the propellant chamber 320 , and urges the contents of the reservoir 330 to the administration site. In one embodiment of the infusion pump, the pump housing is separated into two chambers by a flexible titanium bellows 340 . In this embodiment, the propellant chamber 320 is a sealed compartment that contains a two-phase (liquid-vapor) propellant. The vapor pressure of the propellant exerts pressure on the bellows 340 , which is communicated to drug reservoir 330 , forcing the therapeutic solution from the reservoir 330 , optionally through a filter 350 , and optionally through a capillary flow restrictor 380 , out of the pump via an outlet 310 , through a catheter (not shown) to the intended site within the body.
[0037] In accordance with known technique, the flow rate may be varied by using different lengths and/or diameters of flow restrictive capillary tubing. For a given diameter, the flow rate is directly proportional to the length of the tubing, increasing the length increases the fluid flow restriction resulting in a slower flow rate, while decreasing the length reduces flow restriction and increases the flow rate.
[0038] In a typical embodiment, such as that depicted in FIG. 3 , the housing 370 encloses a collapsible drug reservoir 330 , with an initial internal volume of, for example, 20 ml, or in other embodiments, with an initial internal volume of 35 ml or 60 ml; other volumes may also be selected, limited only by the requirement that the overall size of the housing 370 must allow for implantation. Depending on the size of the drug reservoir 330 selected, the housing 370 may range in thickness, for example from 0.67 inches to 1.2 inches, and may be approximately three inches in diameter.
[0039] In accordance with basic implantable pump technology, the drug reservoir 330 may be refilled periodically and can be accessed transcutaneously by means of a reservoir fill port 300 disposed on the surface of the device housing 370 . In one embodiment, in accordance with known techniques, a stressed elastomeric seal 305 may be punctured with a specially shaped needle (not shown). For example, in one embodiment, the drug reservoir can be refilled by inserting a non-coring needle through the skin of the patient and through a septum, e.g., a silicone septum, to allow additional drug to be delivered to the drug reservoir from outside the patient's body. In one embodiment, the drug reservoir fill port 300 is raised from the outer surface of the device housing 370 such that a clinician can palpate the port 300 from the surface of a patient's body to identify the location and orientation of the port 300 . In an optional embodiment, the drug reservoir port includes an internal needle stop structure 380 intended to limit the needle's travel and to prevent damage to the drug reservoir 330 . Refilling the drug reservoir also recharges the pressure within the propellant chamber 320 , as the change in propellant chamber volume recondenses vapor within the propellant chamber 320 .
[0040] In one embodiment, as depicted in FIG. 4 , the housing 470 has three orifices, one for a catheter outlet 410 , one for an electrode input 490 , and one for the reservoir fill port 400 . Referring to FIG. 4 , the catheter port 410 and electrode port 490 are situated towards the inferior anterior face of the device so a surgeon can easily guide the catheters 415 to the corpora cavernosa and the electrodes 495 to either the cavernous or dorsal nerves of the penis. The refillable port 400 is located on the anterior side of the device. In one embodiment, the port 400 is closed off to the environment by a compressible stage that when penetrated allows a fluid inflow; in this embodiment, the opening of the port will direct a specialized needle into a one-way valve that connects to a refillable drug reservoir bladder. When removing the drug delivery syringe, the compressible stage will return to its original state, sealing the device from the exterior environment.
[0041] FIG. 5A depicts such a drug reservoir fill port 500 in housing 570 . FIG. 5A also depicts a side-view of one embodiment of the invention, including catheter outlet port 510 , catheters 515 , electrodes 595 and housing attachment points 560 . FIG. 5B depicts a cut-away view of the same embodiment, illustrating a catheter outlet port 510 , a propellant chamber 520 , a drug reservoir 530 , attachment points 560 and housing 570 .
[0042] Securing the housing of the device within the abdomen of the patient may be accomplished in multiple ways. Ideally, the device will be secured subcutaneously within the abdomen of a patient via a minimally-invasive procedure. The body of the device may be constructed to have one or more attachment points along its circumference, such as depicted at 360 , 460 and 560 . These attachment points would allow for securing the device to supporting tissue structures with the abdomen of a patient, for example, via sutures or other fixation devices. In an alternative embodiment, the attachment points could be oriented so that the device could be attached to the pelvic bone via standard fixation devices, for example, screws, disposed through the attachment points and secured into the underlying bone. In an alternative embodiment, the attachment points, such as those depicted at 360 , 460 and 560 could be adapted such that the device may be fixed either to bone or tissue structures via sutures. The precise placement of the device is left to the discretion of the clinician; the election of a particular fixation technique does not impact the invention.
[0043] The use of a microfluidic valve to control flow from a constant flow rate infusion pump, such as the above-described pump embodiments, results in reduced size and power requirements as compared to the prior art. Miniature, magnetically latched, solenoid valves allow for high-performance flow switching characteristics, requiring only a momentary (for example, 1 ms) voltage pulse to switch the valve state. Microfluidic valves that provide reliable bi-stable performance, with minimal power drain are readily commercially available, for example, the Series 120 Solenoid Valve available from The Lee Co. (Westbrook, Conn.), part # LFLX0510200B.
[0044] Valves to be used in the described system must be biocompatible and preferably allow only unidirectional flow. In accordance with the invention, the selected valves should require very little power to operate, thereby extending the effective implanted life-span of the system to a therapeutically useful duration. One of skill in the art may select from a number of available microfluidic valves, for example from commercially-available microfluidic solenoid valves, in accordance with these criteria. In one embodiment, the valves 140 are disposed at the distal end(s) of the catheter(s), as depicted in FIG. 1 , in an alternative embodiment, the valves are disposed within, or adjacent to, the pump housing 100 .
[0045] The selected therapeutic drug is delivered from the pump housing to the site of administration via one or more biocompatible catheters 120 . In one embodiment, the catheter will exit the pump housing via a single port 105 , and include a Y-junction 125 so that each of the cavernosal bodies will be in fluid communication with the pump and receive the therapeutic drug. In order to prevent external forces from compressing the catheters and thus causing unwanted dosages to escape, the catheters may be reinforced with a rigid internal structure, such as a titanium inner coil. In addition, the catheters may be adapted to carry electrical signals from the microcontroller to the distal valves, for example, via an embedded insulated wire.
[0046] Implantation of the device housing 200 in close proximity to the pubic bone puts the device in an excellent location for extending the drug delivery catheters 220 to the corpora cavernosa, as depicted in FIG. 2 . In the preferred embodiment, there are two catheters 220 , one each for the left and right corpora cavernosa, and each catheter tip may be secured to the base of the corporal bodies using small sutures. The placement of the distal ends of the catheters is a matter of preference for the surgeon performing the implantation, but it is to be expected that smooth muscle dilation at the very base of the corpora cavernosa will result in the greatest increase in blood flow as the penile arterioles are largest before they enter the shaft of the penis.
[0047] Optionally, the catheters 220 and valves 240 , if situated at the distal end of the catheters, may be coated with one or more compounds to reduce one or more of: host immune response, blood coagulation at the catheter outlet, or the growth of a tissue mass which might occlude the catheter outlet. In addition, the catheters may be coated internally with a substance that prevents particulate build up. A third microfluidic valve may be installed in-line with the catheter 120 , upstream (proximal to the housing) of the Y-junction 125 to be used as a fail-safe mechanism. In accordance with this aspect, if the microcontroller senses that one or both of the distal-end microfluidic valves have remained open beyond the specified duration, the third, upstream valve will be triggered to close, thereby preventing a free-flow situation and overdose. In a similar embodiment, four valves may be provided: two distal valves 140 under normal operational control of the microprocessor as described above to allow dosage, and two fail-safe valves (not shown), each disposed in close proximity, and within the fluid path, to each distal valve 140 . These fail-safe valves are ordinarily open, allowing fluid flow, but can be shut by the microcontroller when a malfunction of the distal valves 140 is detected.
[0048] The system of the invention also provides for input by the patient in order to either trigger release of therapeutic or to arm the system prior to initiating the drug delivery process. In an embodiment where a single control input by the patient is sufficient to trigger drug delivery, any one of a number of typical control input mechanisms may be implanted. For example, the system could register patient input via an implanted subcutaneous button, via an implanted subcutaneous RFID tag or reader, or via other non-invasive communication method including, but not limited to, capacitive touch sensor, vibration sensor, RF control module, or chemical sensor.
[0049] In one embodiment, in order to prevent accidental dosage, a subcutaneous implanted button would require a specific sequence of presses before the microcontroller allows release of the therapeutic. In an exemplary embodiment, as depicted in FIG. 6 , the subcutaneous button would have to be pressed three or more times within ten seconds. In other embodiments, two or more patient input mechanisms must be initiated prior to release of a therapeutic. For example, in one embodiment, an RFID tag keyed to the system may be used to ‘arm’ the system prior to a second patient input, for example, neural input or a button press sequence, the second input registered would then trigger release of the therapeutic. In a preferred embodiment, further user input is filtered out for a period of time after successful administration of therapeutic, thereby preventing overdose and preserving battery life.
[0050] Within the scope of the invention is neurological interfacing, whereby implanted microelectrodes monitor the endogenous neural activity of, for example, the nerves related to the penis. In one embodiment, the microcontroller will analyze the registered action potentials, and the system will release therapeutic in response to signals indicating a sufficiently high state of stimulation. Penile innervation involves both the autonomic and somatic nervous systems; the sympathetic and parasympathetic nervous systems are contained in the cavernous nerves. FIG. 7 is a block diagram depicting the nervous system control that leads to stimulation or inhibition of erection. The cavernous nerves enter the corpora cavernosa and are primarily responsible for the neurovascular events of both erection and detumescence. Somatic innervation of the penis, achieved with the dorsal nerve, is responsible for sensory function and conscious contraction of the local muscles. The autonomic innervation of the penis stems from the pelvic plexus. Branches from the pelvic plexus also innervate the rectum, bladder, prostate and sphincters. These autonomic pathways are responsible for carrying the cerebral impulses to signal erection. There is also evidence that a reflex involving the somatic pathways can stimulate erection without cerebral processing. Through the use of microelectrodes in electrical communication with selected nerves, a patient's own natural neural signals can be sent as an input to the microcontroller. When the nervous signal matches that of true sexual stimulation for a preset period of time, the microcontroller may then trigger release of a predetermined dosage. In one embodiment, the system must be armed, by patient input, prior to monitoring neural activity for stimulatory signals.
[0051] In one embodiment, the cavernous nerves are used as the input source because they transmit signals from the brain that are meant to trigger erection. By intercepting and interpreting these signals, the system of the invention can trigger the release of therapeutic directly into the corpora cavernosa based on endogenous bioelectrical activity intended to cause an erection. Unfortunately, the cavernous nerves may be difficult to access because they are located in very close proximity to the prostate and bladder, and they are not located in a location readily accessible from the typical initial surgical incision. Despite these drawbacks, for a given patient it may be possible for the surgeon to laparoscopically position the electrodes in the correct location.
[0052] In another embodiment, by intercepting signals from the dorsal nerves, release of vasodilator can be triggered by signals that are sensory in nature. For example, if the cavernous nerves are either damaged or inaccessible, or in a case where the patient's central nervous system is incapable of transmitting a signal intended to cause an erection, the physician will still be able to use the device in connection with the dorsal nerves. These nerves are located very close to the pubic bone and are fairly large in size. The dorsal nerves carry sensory signals from the shaft of the penis to the spinal cord and eventually the brain for interpretation; physical stimulation to the penis of a sexual nature will drive a strong sensory response transmitted via the dorsal nerves.
[0053] In an alternative embodiment, both cavernous and dorsal nerves are monitored. In any embodiment, the decision of whether to attach the electrodes to the dorsal or cavernous nerves is contingent on patient specific etiology of ED and accessibility of the nerves; the system described herein may be implanted in the manner most appropriate for the presentation of disease in a specific patient. Electrodes appropriate for use in the disclosed invention are well-known in the art, see, e.g., U.S. Pat. No. 5,215,088, although other electrode designs may be employed with the instant invention; systems for interpretation of neural signaling and control of devices are also well known, see, e.g., U.S. pat. pub. no. 2005/0273890, both of which are incorporated herein by reference.
[0054] Using endogenous neural activity as a trigger for system release of the selected therapeutic provides the most physiologically restorative treatment, as the patient will not be consciously aware of the signal triggering release of the therapeutic.
[0055] In accordance with the invention, when a preset level of stimulation is registered by the microcontroller for a preset length of time, drug release will be triggered. Interpreting the neural signal characteristics that should trigger drug release is governed by the fact that peripheral nerve action potentials have very consistent shapes, and that the level of stimulation is directly proportional to the frequency of action potentials rather than to the voltage amplitude or duration of the action potentials. Therefore, the key indicator of intercepted neural activity that sexual stimulation is occurring is a high threshold frequency. Animal studies (see, e.g., Steers W D, et al. Am J Physiol. 254:989-1000 (1988), incorporated herein) confirm that increased frequency of action potentials corresponds with increased level of stimulation. During the study, the frequency never exceeded 250 Hz; this equates with a period of 4 ms. As 4 ms is approximately the refractory period of peripheral nerve action potentials, regardless of the level of stimulation, a frequency of 250 Hz cannot be exceeded. This same study found that during sexual stimulation the frequency of action potentials in rats was approximately 200 Hz. Based on this, the microcontroller can be programmed to register activity in the range of 150 to 250 Hz, more particularly 150 to 200 Hz, or in some embodiments approximately 200 Hz, as sufficient to register as sexual stimulus as opposed to normal nervous activity. In one embodiment, the microcontroller of the invention is programmable such that the threshold frequency for registering as a sexual stimulus may be modified by a clinician in response to a particular patient's needs, or in response to further human clinical study. For example, if the patient is incapable of achieving an erection due to the lack of a sufficient brain-stimulated impulse, then the microcontroller may be configured to have a lower frequency threshold for registering a sexual stimulus.
[0056] In accordance with this aspect of the invention, the microcontroller must also measure the duration of the registered sexual stimulus prior to triggering drug release. In one embodiment, the microcontroller is programmable to allow the clinician to select the appropriate duration of a registered sexual stimulus prior to drug release. In one embodiment, for example, the duration of registered sexual stimulus must exceed 30 seconds in order to trigger drug release. In another embodiment, registered sexual stimulus must exceed 1 minute in order to trigger drug release. In one embodiment, as depicted in FIG. 8 , the microcontroller will be in a low-power “sleep mode” during periods without sexual stimulation. In such an embodiment, when a sexual stimulus of appropriate threshold frequency is detected, the microcontroller will record the amount of time that the signal frequency is greater than the selected threshold. In one embodiment, if the total time of stimulation does not amount to the selected duration threshold, for example, 30 seconds, within a certain time window, for example, 3 minutes, the sexual stimulus duration counter will reset to zero, and the microcontroller will return to “sleep mode.” If the sexual stimulus duration counter does reach the selected duration threshold during the defined time window, then the drug administration will be triggered. In one embodiment, the microcontroller will be forced to remain in “sleep mode” for a certain period after triggering drug release. This refractory period may be set at any arbitrary time period, including about 24 hours, to prevent recurring drug administration, including drug overdose.
[0057] A standard microcontroller may be programmed to provide control over the drug delivery system. The invention, however, is not limited to any particular computational unit; the only requirement is for a robust, biocompatible, low-power unit that can perform the various recited functions. The microcontroller may be responsible for determining what is considered a sexual stimulus, and maintaining a refractory period post-administration, both as described above, as well as monitoring the quantity of drug in the drug reservoir, controlling the microfluidic valves, including any shut-off valve(s), and interpreting signals from the patient input mechanism(s). The microcontroller may also be programmed to calculate the volume of therapeutic remaining within the drug reservoir by summing and storing the amount of therapeutic administered in each dosage administration, or alternatively, by monitoring pressure changes within the drug reservoir.
[0058] FIG. 9 provides a flow-chart depicting the operation of the system in an embodiment where the microcontroller is responsive to input from a neural interface only after an appropriate signal (or sequence of signals) is received from a patient input mechanism, in the depicted case, an implanted subcutaneous button.
[0059] A patient's dosage may be programmed by the clinician to allow optimization of dosage for each patient, or the dispensed dosage may be preset in accordance with clinical experience. In accordance with known fluid dynamic principles, the dose delivered can be varied by altering the time period during which the microfluidic valves remain open. The proper dosage will be dependent on the selected pharmaceutical, the patient's response to the pharmaceutical, and any other factors the prescribing physician deems relevant. In practice, the flow rate of the constant-pressure pump may diminish slightly over time, as the volume of the propellant chamber increases. Therefore the microcontroller should be programmed to compensate for a decrease in flow rate by allowing for a correspondingly longer duration of valve opening, thereby maintaining the proper therapeutic dosage.
[0060] In accordance with the invention, the microcontroller be maintained in a “sleep mode” or low power consumption mode during times where no sexual stimulus is occurring. In one embodiment, the microcontroller will only exit “sleep mode” after registering a neural stimulus above the selected threshold frequency. In an alternative embodiment, the microcontroller will exit “sleep mode” only after appropriate patient input via the input mechanism is registered. In “sleep mode,” battery power will be used only to power the patient input, sensory input or both, on the microcontroller. Once a patient input or sensory input is registered, the controller will exit “sleep mode” and divert power to the processor's clock. In one embodiment, the clock is used measure the duration of registered supra-threshold sexual stimulus, in another embodiment, the clock is used to test the timing of any patient-initiated input, such as a sequence of activations of an implanted subcutaneous button; in yet another embodiment, the clock may be used to measure both, either sequentially or simultaneously. Additionally, the microcontroller will enforce a refractory period after each dose administration to prevent overdose. Should a patient be instructed by a physician to engage in sexual activity at a limited frequency, for example, no more than twice in any five-day period, the microcontroller may be programmed so that the refractory period corresponds with such limitation.
[0061] In one embodiment, the microcontroller will be remotely programmable by the clinician as to certain operational characteristics, including, but not limited to, the sexual stimulus threshold frequency, the duration of supra-threshold sexual stimulus necessary to trigger drug release, the duration of the forced refractory period, and the drug dosage amount.
[0062] Power for the system, used to power the microcontroller, power the patient input mechanism, and to open and close the microfluidic solenoid valves, can be provided, for example, by a 5 volt lithium ion battery or the like. Calculations show that over the course of a decade of typical use, based on the power draw of the low-power microfluidic valves cited above and a standard microcontroller, such lithium ion batteries have sufficient stored energy to power the device. This is similar to the clinically-relevant lifetime for implantable pacemakers, and one of skill in the art would be able to select an appropriate power source similar to those already in clinical usage which meets the performance requirements of the described system. In addition, for extended implanted lifespan, one embodiment of the system may incorporate an induction charging mechanism.
[0063] As described above, the system is capable of delivering a highly-regulated precision dosage of a therapeutic directly to the corpus cavernosum. In addition, in a preferred embodiment the drug pump reservoir may be refilled multiple times over the life of the device, and the microcontroller may be reprogrammed by medical personnel to deliver a specified dose that differs from the dose initially selected by the prescribing physician. This results in a system that is highly flexible with regard to the choice of therapeutic for administration. Given the currently-approved therapeutics available on the market, papaverine HCl and phentolamine are excellent choices for use with the described system, although other therapeutics may be used. As new therapeutics are approved for the treatment of ED, they may be found to be equally, or more, suitable for administration via the described system. In addition, a physician may elect to change the drug administered by the system over the course of a patient's treatment. Ideal therapeutic candidates would be highly stable in solution at physiologic temperatures for long periods of time, be effective in minimal dosages, be quick acting, and have minimal side effects. Any suitable therapeutic solution meeting these requirements may be implemented with the described system.
[0064] Surgical kits for implantation of the described device may include different undersurface variations for attachment to the housing of the device, a variety of electrode and catheter lengths, as well as electrodes adapted for connecting to either the cavernous nerves or the dorsal nerves. The electrodes may be composed of a metal alloy and insulated with a polymeric insulator, for example, polyurethane. In one embodiment, the distal end of the electrode is fashioned with a shaped tip, adapted to maintain contact with the selected implant location; the proximal end is adapted to enter the device housing and interface with the microcontroller.
[0065] A number of implementations have been disclosed herein with respect to the treatment, cure or mitigation of ED. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the claims, including the use of the disclosed system for the treatment of other ailments. Accordingly, other implementations are within the scope of the following claims.
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Drug delivery systems, apparatus and methods to treat erectile dysfunction via an implanted drug infusion pump. The drug delivery system incorporates a passively pressurized drug infusion pump, one or more catheters, one or more microfluidic valves, a microcontroller, and one or more patient input mechanisms to deliver therapeutic solutions to the erectile tissues of a patient. The system in operation is entirely implanted and provides for moderated patient control over dosage via subcutaneously implanted input mechanisms, including in certain embodiments, neural control.
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TECHNICAL FIELD
The present invention relates to solid-state lasers optically pumped by semiconductor lasers and, in particular, to a method and an apparatus for generating useful laser output from a solid-state laser optically pumped by an unstable resonator semiconductor laser.
BACKGROUND OF THE INVENTION
A variety of methods have been employed for optically pumping solid-state lasers, such as neodymium-doped lithium yttrium fluoride (Nd:YLF) or neodymium-doped yttrium aluminum garnet (Nd:YAG). A common method is to use an arc lamp or other similar light source to excite a laser rod. The light source and laser rod are positioned within and at different foci of a highly reflective housing of elliptical cross-section. This method typically requires relatively large diameter laser rods to efficiently absorb enough of the pumping light emitted by the light source to allow solid-state laser operation. Another limitation of this pumping method is the relative inefficiency caused by poor overlap of the optical emission spectrum of the pumping light source with the absorption bandwidth of the solid-state lasants.
This method typically entails the use of arc-pumped, solid-state lasers, which commonly require water cooling systems that place a severe cumbrance on clean room environments typically preferred for link processing of dynamic random access memory devices performed by, for example, arc-pumped, Q-switched, Nd:YAG lasers.
There are several different methods for diode-pumping solid-state lasers. In U.S. Pat. No. 3,982,201, Rosenkrantz et al. describe a solid-state laser that is pumped by single diode lasers or arrays of diode lasers to which the solid-state laser rod is directly end-coupled. Because the output wavelength of the diode laser array is a function of its temperature, the diode lasers are operated in a pulsed mode at a low duty cycle to maintain the array at a sufficiently stable temperature so that its output wavelength remains matched to the absorption bandwidth of the solid-state laser rod. The output power characteristics of this laser system are limited by the relatively inefficient match between the output of the diode lasers and the mode volume of the solid-state laser rod.
In "Efficient LiNdP 4 O 12 Lasers Pumped with a Laser Diode," Applied Optics, vol. 18, No. 23 (Dec. 1, 1979), Kubodera and Otsuka describe the well-known practice of collecting the output light of a diode laser and focusing its expanded output light using conventional lenses, such as two microscope condenser lenses. This method is particularly well suited for applications where emitter width and divergence of the diode laser are small. However, as the emitter dimensions and beam divergence increase, it becomes increasingly difficult to efficiently collect the output beam with collection lens or lenses. It also becomes more difficult to focus the expanded beam into the solid-state lasant crystal with sufficient depth of focus to allow efficient overlap of the pump beam throughout the resonator mode volume within the lasant.
In U.S. Pat. No. 4,710,940, Sipes, Jr. describes a Nd:YAG solid-state laser that is end-pumped by a diode laser array or by two diode laser arrays that have been combined by use of polarizing beam-splitting cubes. Sipes, Jr., cites the analysis of D.G. Hall in "Optimum Mode Size Criteria for Low Gain Lasers," Applied Optics, 1579-1583, vol. 20, (May 1, 1981), to suggest that the "pump profile shape does not matter much as long as all the pump light falls within the resonator mode." Sipes, Jr., notes, however, that Hall's analysis does not account for the divergence properties of Gaussian beams, so Sipes, Jr., suggests that, if required, the cross-section of the pump beam could be modified by use of a cylindrical lens.
In U.S. Pat. No. 4,761,786, Baer describes a Q-switched, solid-state laser that is end-pumped by a diode laser or diode laser array. The output light from the pump source is collected by a collimating lens and directed by a focusing lens to end-pump the laser rod. Baer notes that "other lenses to correct astigmatism may be placed between the collimating lens and focusing lens." Baer also describes an alternate embodiment that employs a remotely positioned diode laser pumping source coupled through an optical fiber, the output of which is focused by a lens into the laser rod.
In U.S. Pat. No. 4,763,975, Scifres et al. describe two optical systems that produce bright light output for a variety of applications, including pumping a solid-state laser such as a Nd:YAG. Scifres et al. describe an optical system that employs a plurality of diode lasers, each of which is coupled into one of a plurality of fiber-optic waveguides. The waveguides are arranged to form a bundle and the light from the diode laser sources is emitted at the output end of the bundle. Optics, such as a lens, may be used to focus the light into a solid-state laser medium. Alternatively, the fiber bundle may be "butt"-coupled to the laser rod. (Butt coupled means end-coupled at a position very close to or in contact with the laser rod.)
Scifres et al. describe another optical system that employs a diode laser bar, broad-area laser, or other elongated source to pump a solid-state laser. The diode laser bar light output is coupled into a fiber-optic waveguide having an input end that has been squashed to be elongated and thereby have core dimensions and lateral and transverse numerical apertures that correspond respectively to those of emission dimension and lateral and transverse divergence angles of the diode laser bar. The output light from the fiber-optic waveguide is either focused by a lens into the end of the solid-state laser rod or butt-coupled to the rod. Scifres et al. state that either end of the fiber-optic waveguide can be curved. Although these methods attempt to match the output light from the fiber-optic waveguide to the resonant cavity mode of the solid-state laser, they are limited in efficiency by the numerical aperture of the sources that can be effectively collected and guided by the fiber-optic waveguides.
Certain methods are known for efficiently coupling the output of high-power diode lasers into solid-state lasants. High-power diode lasers are necessarily broad-area devices or arrays of narrow-width diode lasers because the potential for catastrophic optical damage to the mirrors dictates the optical outputs be limited typically to 10 to 20 mW per micron of emission stripe width. Typical high-power diode lasers used to pump solid-state lasants include aluminum gallium arsenide (AlGaAs) diode lasers. Examples of such laser diodes include Model No. SDL-2480-P1 with continuous wave (CW) output power of 3.0 watts (W) and an emission width of 500 μm; Model No. SDL-2462-P1 with CW output power of 1.0 W 35 and an emission width of 200 μm; and Model No. SDL-2432-P1 with CW output power of 0.5 W and an emission width of 100 μm, all of which are manufactured by Spectra Diode Labs, 80 Rose Orchard Way, San Jose, California. Use of AlGaAs semiconductor diode lasers to optically pump solid-state lasers has led to development of compact, solid-state lasers.
Broad-area lasers are described by G.H.B. Thompson in "A Theory for Filamentation in Semiconductor Lasers", Optoelectronics, 257-310, vol. 4, (1972) and by P.A. Kirkby, et al. in "Observations of Self-Focusing in Stripe Geometry Semiconductor Lasers and Development of a Comprehensive Model of Their Operation," IEEE Journal of Ouantum Electronics, 705-719, vol. QE-13 (1977). Such broad-area lasers (emission width of typically greater than 5 μm) typically exhibit a filamentary structure in their optical near-field patterns. The filament structures arise from a nonlinear interaction between the carriers and the optical field in the active area of the laser. The process of stimulated emission effectively reduces the gain profile within the active area and results in an increase in the refractive index in the portion of the active area contributing most strongly to the optical mode. This region of increased refractive index is bounded by regions of the active area which do not contribute so strongly to the optical mode and are characterized by smaller refractive index values. This lateral variation in refractive index in a local region within the active area of the diode laser can form a local lateral index guide.
When the active area is broader than about 5-10 μm, as is the case in typical high-power diodes used for solid-state laser pumping, several, or in some cases, many such index-guided regions may form. Stimulated emission within each such lateral index-guided region within the active area may occur in the form of a filament that is only partly spatially coherent or is spatially incoherent with respect to neighboring filaments. This filamentation phenomena is, therefore, a fundamental source of lateral spatial incoherence in high-power laser diodes and, consequently, places limits on the optical brightness obtainable from such devices.
Concurrently filed U.S. patent application of Baird, DeFreez, and Sun for Method and Apparatus for Generating and Employing a High Density of Excited Ions in a Lasant, which is assigned to assignee of the present application, describes a method for employing a high-power diode laser to longitudinally optically pump the mode volume of a solid-state lasant. The high-power diode laser in the preferred embodiment described by Baird et al. is of a type that is typically gain-guided in the lateral plane of the device and index-guided in the transverse plane. Accordingly, the laser diode is typically spatially incoherent in the lateral plane, thus limiting its optical brightness. Baird et al. also describe a method of employing a nonimaging concentrator to efficiently collect optical output from such a high-power diode laser and couple it into the mode volume of a solid-state lasant.
Although these methods have with varying degrees of efficiency been used to optically pump solid-state laser mode volumes and been used to produce useful solid-state laser output at a variety of emission wavelengths, improved methods for coupling the optical output from diode lasers into solid-state lasants are highly desirable. Such methods would be very useful in diode pumping of the new chromium-doped solid-state laser materials such as chromium:lithium calcium aluminum fluoride (Cr:LiCAlF) and chromium:lithium strontium aluminum fluoride (Cr:LiSAlF). These solid-state laser materials are described by S.A. Payne, et al., in "LiCaAlF 6 :Cr 3+ : A Promising New Solid-State Laser Material," IEEE Journal of Ouantum Electronics, 2243-2252, vol. 24, No. 11, (November 1988); S.A. Payne, et al., in "Laser Performance of LiSrAlF 6 :Cr 3+ ," in Journal of Aoolied Physics, 1051-1055, vol. 66, No. 3; and by S.A. Payne et al. in U.S. Pat. No. 4,811,349.
These inhomogenously broadened materials can be optically pumped by aluminum gallium indium phosphide (AlGaInP) laser diodes as described by Scheps, et al., in "Cr:LiCaAlF 6 Laser Pumped by Visible Laser Diodes," IEEE Journal of Ouantum Electronics, 1968-1970, vol. 27, No. 8, (August 1991) and by Scheps, et al., in "Diode-Pumped Cr:LiSrAlF 6 Laser," Optics Letters, 820-822, vol. 16, No. 11, (Jun. 1, 1991). However, the relatively low stimulated emission cross-section-fluorescence lifetime product of these materials implies a requirement for relatively large pump powers to obtain laser operation at threshold by pumping with such broad area, high-power diode lasers. This requirement results from the relatively large pumping beam radius inherent from the lateral spatial incoherence typical of such devices. The optical output of such a broad-area, high-power diode laser coupled via conventional methods into such an inhomogenously broadened material is, therefore, a relatively inefficient process.
A method for theoretically obtaining high-power, nearly diffraction-limited optical output from a high-power laser diode has recently been described by Tilton, . . . DeFreez, et al., in "High Power, Nearly Diffraction-Limited Output from a Semiconductor Laser with an Unstable Resonator," IEEE Journal of Ouantum Electronics, 2098-2108, vol. 27, No. 9, (September 1991). The high-power AlGaAs laser diode described therein demonstrates high power (greater than 1 watt from both facets) and nearly diffraction-limited optical output. The reference states that "[f]or many semiconductor laser applications, such as solid-state laser end pumping . . . , single-lobed, diffraction-limited beams of hundreds of millowatts are required." However, methods for coupling the bright optical output from an unstable resonator semiconductor laser (URSL) into a solid-state lasant have not heretofor been attempted. Furthermore, improvements in development of high-power URSL devices for use as very bright optical pumping sources for solid-state lasers are, therefore, also highly desirable.
Thus, improved methods for coupling the optical output of high-power diode lasers, especially those having improved lateral spatial coherence, into the mode volumes of a laser medium is highly desirable. Such methods for pumping Cr:LiCAlF and Cr:LiSAF to ultimately produce usable frequency doubled optical output in the 360-460 nm wavelength range are described in detail in concurrently filed U.S. patent application of Baird and DeFreez for High-Power, Compact, Diode-Pumped, Tunable Laser, which is assigned to assignee of the present application.
SUMMARY OF THE INVENTION
The present invention is a method and an apparatus for efficient operation of a solid-state laser optically pumped by an unstable resonator semiconductor laser (URSL). The high-power optical output, which exhibits a high degree of lateral and transverse spatial coherence, from the URSL is readily focused to form a pumping beam to longitudinally end-pump a laser resonator cavity containing a laser medium. The pumping beam radius is chosen to be well-matched to the resonator mode radius within the laser medium. The pumping beam is also focused to have a depth of focus within the laser medium to allow excellent absorption of the pumping beam by that part of the laser medium contained within the resonator mode volume.
An object of the present invention is, therefore, to provide a longitudinally URSL-pumped, solid-state laser.
Another object of this invention is to provide an optical system incorporating a URSL and lens system that cooperate to generate a very bright optical output useful for optically pumping laser resonators.
A further object of this invention is to produce a longitudinally URSL-pumped solid-state laser in which the laser rod is Cr:LiCAF or Cr:LiSAF and in which the solid-state laser reaches laser operation at relatively low pumping power output.
FIG. 1 is a graphical representation of exemplary analytical data depicting output power vs. diode-pumping power applied to a Cr:LiCAF laser. The data illustrate the operation of a Cr:LiCAF laser achieved with pumping power supplied by a broad-area diode laser (slope A) and by an URSL (slope B), each having equal emission widths and cavity lengths. Slope A demonstrates that an URSL of the present invention provides not only a reduction in threshold, but also provides a substantially better slope efficiency. A person skilled in the art will appreciate that these differences are generally true regardless of changes made to the numerous variables used to calculate the data illustrated in FIG. 1.
Additional objects and advantages of the present invention will be apparent from the following detailed description of preferred embodiments thereof, which proceeds with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a graphical representation of analytical data illustrating the differences in diode output power for operation of a Cr:LiCAF laser when pumped respectively, a broad-area diode laser and an URSL, each having equal emission widths and cavity lengths.
FIG. 2 is a partly schematic plan view of a preferred embodiment of a laser system incorporating an unstable resonator semiconductor laser (URSL), a lens system, and a solid-state lasant in accordance with the present invention.
FIG. 3 is an enlarged side view of a lens system that is used to couple output light emitted by the URSL into the solid-state laser resonator cavity of the laser system of FIG. 2.
FIGS. 4A and 4B are respective enlarged plan and side elevation illustrations of an URSL incorporated in the laser system of FIG. 2.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
With reference to FIGS. 2 and 3, laser system 10 includes a power supply 12 for supplying electrical current to a high-power URSL 14 with an optical output power of greater than 250 mW to pump a solid-state laser resonator cavity 16 having a cavity length 18 of about 15 mm. High-power URSL 14 forms part of a laser diode package 20 that is connected to a heat sink 22. High-power URSL 14 is positioned so that its optic axis 24 (FIGS. 4A and 4B) may be substantially coaxial to an optic axis 26 that extends through resonator cavity 16 of a solid-state laser 28. A processing unit (PU) 30 determines the power level and other signal levels supplied by power supply 12 to high-power URSL 14.
High-power URSL 14 can be fabricated by focused ion beam micromachining its end surfaces to have predetermined radii of curvature, as described in Tilton, . . . DeFreez, et al. With reference to a preferred embodiment shown in FIGS. 4A and 4B, a broad-area, high-power AlGaInP semiconductor diode laser, which typically emits at wavelengths in the range 610 nm to 690 nm has one or both mirrors 40 and 42 micromachined to have respective radii of curvature 44 and 46 such that the combination of mirror curvatures 44 and 46 yield imparts a greater than unity lateral magnification to an optical field propagating within high-power URSL 14. For example, a high-power URSL 14 may have a cavity length 50 of 500 μm, an active area width 52 of 200 μm, an active area thickness 54 of 0.005-2.0 μm, and a mirror 42 with spherical radius of curvature 46 of infinity. Such a high-power URSL 14 could have a mirror 40 micromachined to have a spherical radius of curvature 44 of 2200 μm with maximum sag depth 56 of 2.3 μm along URSL optical axis 24 of high-power URSL 14 with respect to its unmachined facet plane 58. Such a high-power URSL 14 would have a resonator magnification of about 2.5.
Unlike conventional high-power diode lasers and arrays of diode lasers used for pumping solid-state lasants, high-power URSL 14 exhibits lateral spatial coherence as well as transverse spatial coherence. This improvement in spatial coherence results in high-power URSL 14 generating a high-power optical output 60 (typically greater than about 0.1 W and preferably greater than 0.25 W) that can be efficiently collected by a lens system 70, which typically includes a collection lens and a cylindrical lens. Optical output 60 is subsequently focused by an objective lens 72 to form an optical pumping beam 74 that has its radius and depth of focus selected to be well-matched to the radius and length of a lasant mode volume 76. The lasant mode volume 76 constitutes the portion of mode or beam volume 78 of resonator cavity 12 that is contained within lasant 80.
Analyses suggest that adjustments to the radii of curvature 44 and 46 of the respective mirrors 40 and 42, in combination with adjustments to the cavity length 50, can modify divergence angle 92 originating from virtual point source 90 in the lateral plane to make angle 92 substantially equal to divergence angle 96 originating from real point source 94 in the transverse plane of high-power URSL 14.
Employing high-power URSL 14 to generate optical pumping beam 74 allows efficient pumping of a generally cylindrical lasant mode volume 76 having a small radius (less than 50 μm). This arrangement effectively reduces the power of optical output 60 required from high-power URSL 14 to obtain threshold operation of solid-state laser 28. Furthermore, optical pumping beam 74 is preferably selected with lasant mode volume 76 to produce TEM 00 mode laser operation, a useful property which allows optical output 100 from resonator cavity 16 of laser system 10 to be readily focused by conventional optical methods.
Lasant 80 is preferably a chromium-doped crystal, such as Cr:LiSrAlF 6 (Cr:LiSAlF) or Cr:LiCaAlF 6 (Cr:LiCAlF), positioned along optic axis 26. The preferred dopant level for Cr:LiSAlF or Cr:LiCAlF lasants 80 employed in the present invention is greater than 1.0% atomic. Skilled persons will appreciate that lasant 80 may be any chromium-doped fluoride composition of Cr 3+ :XYZF 6 wherein X is Li + , Na + , K + , and Rb + , Y is selected from Ca 2+ , Sr 2+ , Ba 2+ , Cd 2+ , and Mg 2+ , Z is selected from Al 3+ , Ga 3+ , and Sc 3+ . Furthermore, lasant 80 may alternatively be doped with a rare earth ion selected from neodymium, holmium, erbium, and thulium.
A dichroic coating 104 is applied to a preferably curved surface 106 of a rear resonator mirror 108. Dichroic coating 104 is highly transmissive at the preselected high-power URSL pump wavelength such as 650 nm and highly reflective at a preselected solid-state lasant emission wavelength such as 780 nm. Lasant surfaces 112 and 114 may be coated for high transmission at the lasant emission wavelength, and may have respective wedge angles 116 and 118, which may be the Brewster's angle defined by the emission wavelength and polarization. An output coupling mirror 120, which is partly transmissive at the lasant emission wavelength and which may have a radius of curvature, forms the opposite end of resonator cavity 16.
In the preferred embodiment, resonator mirror 108 has a radius of curvature of 100 mm and output coupling mirror 120 has a radius of curvature 20 mm. The radii of curvature are chosen in conjunction with cavity length 18 and the geometry of lasant 80 to provide a resonator mode beam waist or radius waist that permits low threshold laser operation. Lasant 80 has a length of about 5 mm and has a rectangular cross section of 4 mm ×5 mm. A TEM 00 mode radius waist of less than 40 μm is located within lasant mode volume 76 near lasant surface 112. Optical pumping beam 74 is focused to have a beam radius well-matched to the TEM 00 mode radius throughout lasant mode volume 76. Skilled persons will appreciate that in FIG. 2, mode or beam volume 78 is shown greatly enlarged for ease of visualization and does not represent a true path through the other elements in FIG. 2.
In an alternate embodiment, resonator mirror 108 is eliminated and dichroic coating 104 is applied to lasant surface 112 so that it forms one reflective surface of resonator cavity 16. When used as one of the reflective surfaces of resonator cavity 16, lasant surface 112 may be fabricated with an appropriate radius of curvature.
In another embodiment, high power URSL 14 is composed of the conventional light-emitting semiconductor material AlGaAs. In this embodiment, lasant 80 may be a neodymium-doped laser crystal, such as Nd:YAG or Nd:YLF, or a stoichiometric neodymium material such as LNP, all of which have spectral absorption bandwidths that can be matched to the emission spectrum of a high-power AlGaAs URSL by wavelength selection of the URSL. Temperature tuning the emission wavelength of the laser diode may also be employed as needed. Temperature tuning is well-known to the art and is described, for example, in "Laser Diode Guide Book," Sony Corporation of America, p. 52.
It will be obvious to those having skill in the art that various changes may be made in the details of the above-described embodiments of the present invention without departing from the underlying principles thereof. For example, high power URSL 14 can be composed of other light-emitting semiconductor materials such as InGaAsP or ZnSe. Furthermore, solid-state lasant 80 may comprise other lasant crystals such as those doped with a rare earth ion such as holmium or erbium. The scope of the present invention should, therefore, be determined only by the following claims.
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High-power optical output (60) that exhibits a high degree of lateral and transverse spatial coherence from an unstable resonator semiconductor laser (14) is efficiently optically coupled into a lasant mode volume (76) of a solid-state laser (28). This apparatus and method of pumping enable the preferred lasants, Cr:LiCAF and Cr:LiSAF, to reach laser operation at a reduced pumping level.
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The present invention relates generally to shaft assemblies which are variable in length and more particularly to a shaft assembly which is adaptable for use as the steering shaft in steering devices of motor vehicles.
The invention generally relates to assemblies which comprise at least two coaxially arranged shaft members, with at least one of these shaft members being formed as a tubular piece into which the other member is inserted by its end piece and is slidably mounted therein, but held for mechanical transmission of torque. The outer peripheral contour of the inner member matches the inner peripheral contour of the outer member at least areawise and there is arranged between paired portions of the members a sliding sleeve enabling axial displacement therebetween, the sliding sleeve being made of macromolecular material which is firmly connected with one of the shaft members.
In the prior art, shafts of this kind are known, for example, from British Pat. Nos. 1 328 200 and 1 542 127, wherein there are disclosed designs of such shafts which may be used as steering shafts for motor vehicles. In such devices, one section of the steering shaft is mounted on the vehicle body, for example, on a part of the dashboard and the other section or shaft member is mounted on the axle of the vehicle. During the final assembly of the vehicle, the two parts are fitted together. During operation, these parts of the steering shaft will move axially relative to each other since the axle portion on which the steering shaft assembly is mounted will move relative to the vehicle body. In such assemblies, some play, albeit slight, must exist between these parts of the shaft assembly. This is necessary in order that the steering shaft or the sections thereof forming the steering assembly may be fitted together in the final assembly without special effort and without the aid of special tools. Also, the play is necessary in order to enable the fitted parts to move relative to each other without frictional losses during operation.
However, it has been found that play, which is provided for these purposes, tends to impair ease of steering.
Accordingly, the present invention is directed toward providing an improved steering shaft assembly of this type which may be variable in length and which may be used particularly for motor vehicle steering shaft assemblies to the effect that this necessary play may no longer be perceived by an operator of the motor vehicle.
SUMMARY OF THE INVENTION
Briefly, the present invention may be defined as a shaft assembly capable of length variation, particularly suitable for use in the steering shaft assembly of a motor vehicle, comprising at least two axially arranged shaft members telescopically joined together to effect mechanical transmission of torque, said members comprising an outer tubular member and an inner member slidably inserted within the outer member. The outer member is formed with an inner peripheral wall and the inner member defines an outer peripheral wall, with said inner and outer peripheral walls being shaped for complementary interfitting relationship. A resilient sleeve made of macromolecular material is fitted between the inner and outer peripheral walls in order to effect sliding interfitting engagement between the shaft members, said sleeve being firmly affixed on one side thereof to one of the inner and outer members. The sleeve is formed with pairs of resilient fins which extend longitudinally along the sleeve on the side thereof opposite said one side which is firmly affixed to said one member. The resilient fins extend into engagement with the other shaft member, with the fins being thereby subjected to resilient deformation to apply a resilient force between the inner and outer shaft members.
The resilient fins operate to provide the advantages, in accordance with the invention, in that they protrude into a free space defined between the shaft members and extend in the axial direction of the shaft assembly in order to apply against the walls thereof a resilient force, whereby the fins are subjected to deformation. In addition to improved ease of steering which is effected thereby, the arrangement in accordance with the invention, also permits a simple and play-free vertical and/or longitudinal adjustment of the steering wheel so that expensive serrations which have until now been used can be avoided.
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 use, reference should be had to the drawings and descriptive matter in which there are illustrated and described preferred embodiments of the invention.
DESCRIPTION OF THE DRAWINGS
In the drawings:
FIG. 1 is a front view of a steering shaft assembly in accordance with the invention;
FIG. 2 is a sectional view of the shaft assembly shown in FIG. 1;
FIG. 3 is a transverse sectional view taken along the line III--III of FIG. 2;
FIG. 4 is a transverse sectional view taken through the sliding sleeve of the invention;
FIG. 5 is a side view of the sleeve depicted in FIG. 4; and
FIGS. 6 and 7 are transverse sectional views taken through other embodiments of steering shafts in accordance with the present invention and depicting the cross-sectional configuration thereof.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the drawings, and more particularly to FIGS. 1-5, wherein there is depicted a first embodiment of the invention, the shaft assembly, in accordance with the invention, is shown as basically consisting of a first shaft section or member 1 having a solid cross-section which carries at one end thereof a shaped part or attachment member 3 adapted to enable other parts of a steering device to be connected with the assembly of the invention. The shaft member 1 is essentially formed as a rolled, cold-extruded or drawn member from solid material and its cross-section is best seen in FIG. 3. This cross-sectional configuration of the member 1 is formed with rounded corner areas between which there are defined indentations or grooves 5, the transition between the corners and the grooves being gradual.
A second shaft member 2 which carries a hinge pin 6 at the end thereof is formed as a tubular member and is shaped with an internal cross-sectional configuration which approximately matches the external configuration of the shaft member 1. The internal configuration or wall of the outer member 2 and the outer peripheral configuration or wall of the internal or inner member 1 are shaped for complementary interfitting engagement and, as best seen in FIG. 3, the outer shape of the shaft section 1 approximately matches the inner peripheral wall of the tube 2 inasmuch as the hollow tubular member 2 is formed with rounded corner areas and grooves therebetween having an overall configuration conforming with the member 1. The inner dimensions of the outer member 2 and the outer dimensions of the inner member 1 are so different that between the two parts considerable play exists. Thus, it will be seen that a gap is provided between the members 1 and 2. In order to bridge this gap and overcome the play created thereby and to support sliding of the members 1 and 2 relative to each other, there is attached at the inner member 1 a sliding sleeve 7 made of suitable plastic material having a low coefficient of friction whose peripheral contour matches that of the member 1 upon which it is carried. The sleeve 7 has a wall thickness S which is dimensioned such that it bridges the gap between the members 1 and 2 so as to reduce the play therebetween, with the sleeve section carried by the member 1 and connected therewith applying against the wall of the outer member 2 only areawise, so that there remains free spaces 8 between the outer wall of the sleeve 7 and the inner wall of the outer member 2.
The wall thickness S of the sliding sleeve 7 is further dimensioned so that no major pressure acting in the radial direction is exerted on it by the receiving section or member.
The sliding sleeve 7 which is utilized in the embodiment of the invention described herein is best illustrated in FIGS. 4 and 5 and is there shown as being formed at diammetrically opposed points with pairs of lips or fins 9 which extend longitudinally in the axial direction of the sleeve 7 over a length dimension L thereof and radially therefrom. The fins or lips 9 are formed with beveled end faces 10.
The fins 9 are also dimensioned with a radial height h which is somewhat greater than the distance of the free space 8 defined between the outer wall of the sleeve 7 and the inner wall of the outer shaft member 2 so that, when the shaft member 1 with the sleeve 7 mounted thereon is inserted into the hollow shaft member 2, the fins or lips 9 will be deformed, as seen in FIG. 3, and thus, will create a resilient or spring force in both directions of rotation indicated by arrow 11, thereby bringing about a characteristic for the steering mechanism, such that the person or operator of the steering mechanism will no longer have the sensation that play exists between the two shaft members 1 and 2. The wall thickness S of the sliding sleeve 7 is dimensioned so that, although it bridges the gap or play existing between the members 1 and 2, it is not thereby stressed in the radial direction, since it must be possible, of course, to move the assembled sections 1 and 2 relative to each other without special effort and without special frictional losses.
The described effect of the sliding sleeve 7 is further improved by insertion of a solid cord or member 12 of permanently elastic material, for example, a rubber cord, between the two fins or lips 9 before the shaft members 1 and 2 are fitted together. Due to the beveled end faces 10 on the ends of the fins 9, the cord 12 can be inserted together with the shaft member on which it is mounted without special effort and without the aid of special tools. The cross-section of the rubber cord 12 is appropriately selected so that it is somewhat greater than the spacing between the fins 9 forming each pair of fins when they are not under load, i.e., as seen in FIG. 4, so that the rubber cord 12 inserted between the unstressed fins 9 will be retained in a clamped position.
Of course, it will be appreciated that the invention may be provided in shapes and configurations deviating from that shown in FIG. 3, and thus, another embodiment of the invention is shown in FIG. 6, wherein a different cross-sectional form for the sliding sleeve 7 is provided which is again fixedly mounted on the shaft part 1.
A further embodiment of the invention is shown in FIG. 7.
In the embodiment of FIG. 6, three pairs of fins 9 are provided whereas, in the embodiment of FIGS. 1-5, two pairs of fins 9 were provided.
In FIG. 6, the pairs of fins 9 are shown radially equally angularly spaced about the sliding sleeve 7.
In the embodiment of FIG. 7, the fins 9 are arranged on the inner side of the sliding sleeve 7 as opposed to being arranged on the outer side thereof in the embodiments of FIGS. 1-5 and 6. The sliding sleeve 7, in the embodiment of FIG. 7, is connected with the inner wall of the outer shaft member 2.
Although the embodiments of FIGS. 1-5 and FIG. 6 are the preferred embodiments, the embodiment of FIG. 7 will be found to suitably fulfill the desired purpose, although the other embodiments may exhibit greater ease of assembly.
Thus, from the foregoing, it will be seen that the invention has been described with reference to a steering shaft assembly for the steering device of a motor vehicle. However, it will be understood that the invention is not limited to use in this connection and that it may be appropriately employed wherever a shaft which is variable in length, that is, a telescoping shaft is to be structured to have a minimum play.
Furthermore, although a solid inner shaft member 1 has been shown in the embodiments discussed herein, it should be noted that it is also possible to utilize a hollow member for the shaft member 1, especially when the shaft is large, as, for example, in steering devices for large trucks. In the wall of the sliding sleeve 7, depressions may be provided or also perforations or openings into which lubricant and/or anti-corrosive materials may be introduced before the parts are assembled. Moreover, it is possible to shape the cross-sectional configuration of the parts so that the parts may be fitted together only in a predetermined radial position. For this purpose, the sliding sleeve may be utilized in that its wall thickness may differ taken in the circumferential direction.
Thus, in accordance with the foregoing, it will be seen that the present invention provides a steering shaft assembly for the steering devices of motor vehicles, wherein two axial members 1 and 2 are inserted one within the other and are displaceable one within the other, while in service. The outer peripheral contour of the inner member 1 and the inner peripheral contour of the outer member 2 are made in a matching or complementary configuration with a sliding sleeve 7 being arranged in the space between the two shaft members. On the side directly opposite the member 1 or 2, displaceable relative to it, the sliding sleeve 7 comprises pairs of spaced lips or fins 9 extending substantially in the longitudinal direction of the sleeve 7 and radially therefrom. The fins 9 protrude into the free space 8 defined between the paired shaft members 1 and 2 and they extend in the axial direction of the shaft and apply against the wall thereof a spring force as a result of deformation of the fins. Owing to this, play between the shaft members 1 and 2 which necessarily exists in such steering shaft assemblies will no longer be perceived by an operator of the motor vehicle, and thereby ease of steering will be enhanced.
While specific embodiments of the invention have been shown and described in detail to illustrate the application of the inventive principles, it will be understood that the invention may be embodied otherwise without departing from such principles.
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A variable length shaft assembly particularly for steering shafts in motor vehicles, wherein a pair of telescopically axially displaceable shaft members have a resilient sliding sleeve interposed therebetween, with the sleeve being affixed to one of the shaft members and with pairs of radially extending fins formed longitudinally along the sliding sleeve being radially directed toward the other shaft member to effect deformation and a resilient force attending to eliminate the feeling of play between the shaft members during operation of the steering assembly.
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BACKGROUND, BRIEF SUMMARY AND OBJECTS OF THE INVENTION
The present invention is directed to an apparatus for and method of handling and closing one end of circular knit hosiery blanks.
It has become a common practice to close the toe portions of hosiery blanks by guiding the blanks to a sewing machine. Several automatic machines for carrying out the toe closing operation on a plurality of hosiery blanks by sucessive operational steps are disclosed, for example, by U.S. Pat. Nos. 3,941,069 and 3,859,938. Normally an operator picks up the welt portion of a hosiery blank and holds the toe end in front of a suction tube so as to draw the toe end of the blank into the tube. The operator then draws the blank from within the tube over the outside of the tube thus everting the blank. At the same time the toe end portion is positioned at a specific location on the tube.
In the present invention, a number of the manual operations required in positioning a blank on a loading tube have been eliminated, thus the loading operations are carried out with a minimum of labor.
In one embodiment of the invention, the system includes a hosiery blank support unit having loading fingers displacable in a circular path about a hub. A binder or clamp is attached to a first loading finger for retaining the welt portion of the blank. The loading fingers expand in response to a fluid cylinder to spread the welt portion. A drive motor displaces the garment to a position where the toe end of the blank is drawn by suction into a loading tube. Continued displacement of the blank carries the blank over the exterior of the tube. The loading fingers then collapse, leaving the blank on the tube. The support unit and loading fingers continue to rotate to the original starting position ready to accept a new hosiery blank.
In an alternate embodiment, a plurality of blank support units radiate from the hub. The hub and support units may be controlled to rotate continuously at a selected speed or at intermittent steps having a selected time interval between successive steps.
One of the primary objects of the invention is the provision of a system for loading hosiery blanks onto loading tubes of an automatic toe closing machine.
Another object of the invention is the provision of a novel arrangement for carrying out the loading of blanks with increased productivity by eliminating certain manual operations.
Still another object of the invention is the provision of a new and improved system for decreasing operating costs.
Other objects and advantages of the invention will become apparent when considered in view of the following detailed description.
IN THE DRAWING
FIG. 1 is a side elevational view of one embodiment of the loading apparatus of the present invention;
FIG. 2 is a schematic, diagrammatic top plan view of the loading mechanisms, two automatic toe closing machines and the location of an operator for positioning hosiery blanks upon the loading fingers;
FIG. 3 is a fragmentary, perspective view of the positioning of two automatic toe closer machines, and also illustrating the opened loading fingers prior to displacing a blank over a loading tube;
FIG. 4 is a schematic, fragmentary, top plan view of the loading unit of FIG. 1;
FIG. 5 is an enlarged view of the expanded loading fingers as they displace a blank over the loading tube;
FIG. 6 is a schematic diagram of the program motor and control cams;
FIG. 7 is a top plan view of a modified loading apparatus of the present invention illustrating a plurality of equally spaced loading support arms and loading fingers; and
FIG. 8 is a schematic block diagram of the various control components.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIG. 1, the mechanism 10 for positioning hosiery blanks upon the loading tubes of an automatic toe closing machine includes a support structure 12, a hub assembly 14 and a blank support unit 16.
The support structure 12 consists of a stand having legs 18 and a plate 20, and an upright bracket 22 secured to the plate 20. Attached to the upper end of bracket 22 and to the base plate 20 are a pair of shaft bearings 24,24 for rotatably blade supporting the hub assembly 14.
The hub assembly 14 includes a vertically disposed hollow shaft 26 which has the support unit 16 attached to the upper end thereof. An arm 28 of the support unit is fixedly secured adjacent one end to the upper end of shaft 26 for rotation therewith. The other end of the arm 28 is generally L-shaped, as shown most clearly by FIGS. 2, 4 and 5 and defines a loading finger 30. A second finger 32, corresponding generally in size and configuration to that of finger 30, is mounted in vertically spaced parallel relation with finger 30. The finger 32 is attached to the piston rod 34 of the fluid cylinder 36, which, in turn, is fixedly secured to the arm 28. A guide rod 38 is secured to the displacable finger 32 and extends through an opening in the arm 28 for providing stability to the finger 32 and for retaining such finger in alignment with the finger 30. Attached to the upper finger 30 is a clamp or binder element 44 for retaining a hosiery blank 42 upon the support unit when the fingers are in the collapsed position. The clamp 44, FIG. 5, may be of spring steel construction having a generally L-shaped configuration and having a portion 46 normally biased into engagement with the upper surface of finger 30. In placing a hosiery blank 42 on the support unit 16, the blank welt end is placed between the binder clamp surface 46 and the upper surface of finger 30 and depends below the finger 32. Upon activation of the air cylinder 36 the fingers expand, thus opening the welt end of the blank.
A sensor 50, which may be a photo electric switching device, is positioned to be adjacent to fingers 30, 32 when the support unit 16 is in the loading position A, FIG. 4. The sensor may be fixedly supported by any siutable means. In the embodiment illustrated, the sensor 50 is supported upon a bracket 52 secured to the stand 12.
The cylinder 36, which controls displacement of the fingers 30, 32 between expanded and collapsed positions, is activated by conventional valve 39 which controls air flow through supply line 40, a rotary union 54 connected to the lower end of the hollow shaft 26, the shaft 26, and the air line 41. The fluid cylinder is of the type provided with a return spring 43.
The shaft 26 has a pulley 60 and a drive cam 62 secured to the lower end thereof. The support unit 16 shaft 26, and cam 62 are selectively indexed in a prescribed manner from a drive motor 66, belt 68 and drive pulleys 60, 61.
The loading apparatus 10 is used in conjunction with automatic toe closing mechanisms. Referring to FIGS. 2 and 3, automatic toe closing machines 70, 72 are provided. The machines may be of a type manufactured by Takatori Machinery Works, Inc., and as disclosed by U.S. Pat. No. 3,941,069. Each toe closer is provided with a plurality of support units 74, each of which includes an elongated tube 76 having opposed finger pieces 78 capable of being axially selectively displaced relative thereto. Wind on wheels 79 position the blanks on the tubes, and the finger pieces 78 are projected to present the toe end of the blanks to sewing instrumentalities 77.
In the operation of the system, the arm 28 and fingers 30, 32 are initially at rest at position A, FIG. 4, and with the fingers 30,32 in a collapsed condition.
An operator picks up a garment blank 42 and inserts a portion of the welt end between the finger 30 and the spring clip 46. Since the fingers are collapsed, the lower finger 32 also is within the open end of the hosiery blank 42.
At the instant the blank is clamped by the spring clip, a photo electric switching device 50 senses the blank and through a control circuit 80, solenoid valve 82 and cylinder 36, the finger 32 is moved away from finger 30 to stretch or open the welt end of the hosiery blank, as shown by FIG. 3. Also at this time, a signal is received from the control circuit of a toe closer machine 70 to operate momentarily through control circuit 80 to remove the motor braking circuit and apply power to the drive motor 66. As the motor operates, drive cam 62 is rotated to maintain power to the drive motor. After approximately 100 degrees rotation of the drive cam, arm 28 and fingers 30, 32 having the blank thereon move to the position B, FIG. 4, the cam deactivates through circuit 80 power to the drive motor 66 and the motor brakes are reapplied.
With the fingers 30, 32 in position B, the toe closer 70 operates in a conventional manner and a loading tube 76 is indexed into position and suction in the tube picks up the blank toe portion drawing it into the tube, as show by FIG. 3, for subsequent everting of the blank. The control circuit 80 then activates the sequence program circuit 90 which includes the motor 92 and control cams 94-100 and their respective switches 102, 104, 106, 108. As the motor 92 rotates the cams, switch 104 is closed thus activating the driving motor 66 to move the fingers 30, 32 and blank 42 to position C. As the arm 28, and fingers 30, 32 are displaced the open or stretched welt end of the blank is moved over and along the outside of the loading tube 76 toward the wind-on wheels 79. As the blank reaches the wind-on wheels, switch 106 is operated deactivating the drive motor 66. The wind-on wheels 79 strip the blank 42 from fingers 30, 32 and wind the blank completely on the tube 76 for subsequent positioning of the blank toe portion for sewing. Upon continued rotation of the motor 92 and the cams 94-100, switch 106 is again operated energizing drive motor 66 thus rotating the arm 28 and fingers 30, 32. Continued rotation of the cams operate switch 108 which through the control circuit 80 solenoid valves 82 and fluid cylinder 36 causes the fingers 30, 32 to close at position D. The sequence program motor 92 has now completed one revolution and stops. The drive motor 66 continues rotation of the arm 28 and fingers 30, 32 to position A. The drive cam 62 deactivates the drive motor 66 at position A when the arm 28 and the fingers complete one full revolution. The fingers in the collapsed condition are now ready to receive another hosiery blank.
In the past, an operator has been required for each toe closing machine. With the use of the automatic loading assembly of the present invention an operator may operate more than one machine. As shown, for example by FIG. 2, an operator may be positioned adjacent plural, selectively located, automatic loading assemblies 10, 10A and toe closure machines 70, 72 for picking up hosiery blanks from a point and alternately placing the blanks on the rotating support units 16, 16A. Rather than having an operator load an automatic loading assembly, a robot may be provided for picking up blanks arranged in a prescribed manner at a supply station and placing the welt end of the blank on the loading assembly for subsequent spreading of the welt end by the fingers 30, 32.
Referring to FIG. 7, the automatic loading mechanism may include a plurality of hosiery blank support units 16A attached to a common hub assembly. The support unit 16A may be controlled to rotate continuously at a selected speed on in intermitant steps having a selected time interval between successive steps. In the embodiment of FIG. 7, the support units 16A are loaded simultaneously by an operator or robot each time a support unit indexes or rotates passed the loading station A. While six support units 16A have been shown, it is to be understood that the number of units may be varied depending on the operational speed of the hub assembly, the operational speed of the indexing tube 76 of the toe closing machine, etc.
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A system for automatically closing the toe portions of tubular hosiery blanks includes an automatic loader assembly for receiving, supporting and spreading open an end portion of a hosiery blank, for transporting the blank to a toe closing machine, and for carrying the opened end of the blank over a loading tube of a toe closing machine while everting the blank.
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BACKGROUND
1. Field
This application relates to coupling devices specifically to such coupling devices which are used with hose, pipe, conduits, tanks, fittings and the like where the couplings have components which prevent interchangeability.
2. Prior Art
In U.S. Pat. No. 2,518,026 a Coupling, is disclosed that is commonly called a Camlock Coupling today. This Camlock Coupling is in general use today across a wide variety of industries. It is used for making quick release, fluid tight connections between hose, pipe, conduits, tanks, fittings and the like to facilitate the transport of liquids, solids and slurries.
The delivery of fuel to gas stations is an example of an industry that makes extensive use of Camlock Couplings for loading tanker trailers at fuel depots and unloading fuel from tanker trailers into storage tanks at gas stations. A typical tanker trailer will carry and unload a combination of diesel fuel, various grades of gasoline and ethanol based fuels. The Camlock Coupling used on the hose connections and related fittings is the same size and design regardless of the fuel being loaded or unloaded and this can result in cross contamination or accidental mixing of fuels in both the tanker trailer or more commonly in the storage tank at the gas station. For instance it is all too easy to connect a hose between the diesel compartment of the tanker trailer and the regular gasoline storage tank at the gas station since all the Camlock Coupling connections are identical. Even with procedures, color coding and tagging systems in place these “crossovers”, as the industry refers to them, are all too common and costly to rectify. Diesel and gasoline mixes that end up in customer vehicles can result in expensive engine repairs and a serious loss of reputation in the marketplace for the oil company. Mixes can also result in motorist and boaters, becoming stranded with engine failure which can be a serious safety issue and a potential liability concern for Oil Companies.
Standard Camlock Couplings and related fittings and accessories are not designed to prevent crossovers. Thus a coupling that can be configured for a specific fuel from the tanker trailer discharge to the storage tank inlet and all the fittings and hose connections in-between would eliminate the potential for crossovers. This and other advantages will become apparent from a consideration of the ensuing description and accompanying drawings.
SUMMARY OF THE INVENTION
According to the invention there is provided a quick-disconnect coupling comprising:
a hollow male plug member having an external peripheral groove,
a hollow female socket member defining an opening into which the male plug member can be inserted so as to be moved therein to a locking position;
the male plug member and female socket member defining a duct passing therethrough for communication of a fluid therebetween;
a locking arrangement for locking the male plug member in the female socket member at the locking position;
at least one protrusion provided on either an inside surface of the female socket member or on an outside surface of the male plug member;
at least one recess provided on either an inside surface of the female socket member or on an outside surface of the male plug member;
said at least one recess and said at least one protrusion being cooperatively shaped arranged to allow insertion of the male plug member into the female socket member to the locking position when said at least one recess and said at least one protrusion match.
Preferably there is provided a plurality of protrusions and a plurality of recesses at a predetermined spacing therebetween and wherein insertion of the male plug member into the female socket member to the locking position is allowed only when said predetermined spacing matches. However a single protrusion and associated recess can be used where they are set at a predetermined angle around the coupling and/or have a predetermined dimension and height.
Preferably there are provided elements identifying the location of the protrusions and recesses when the male plug member and the female socket member are connected and when they are separated so as to ensure alignment when relative movement is undertaken. That is the user can see the location of the elements to ensure that they are aligned as the user tries to insert the components or to separate.
That is for example the rotational and axial alignment for assembly and disassembly of the coupling can be made evident by way of the protrusions and recesses themselves and/or by the inclusion of additional alignment marks on the female socket member and/or on the male plug member of the assembled coupling.
Preferably the male plug member has an external peripheral groove for engagement with the locking arrangement of the female socket member and the protrusions and recesses are located to prevent movement of the groove to the locking arrangement unless aligned. This allows that the female socket member and the male plug member can be rotated relative to each other after assembly. That is the recess and the protrusion do not cooperate with the locking arrangement, which can be a cam lock, to hold the components connected but act as a restriction to allow the locking arrangement to engage only when the recess and protrusion match.
Preferably the protrusions are located on the female socket member and align with the groove when the male plug member is moved to the locking position.
Preferably there is provided a sealing member for sealing between the male plug and the socket in the locking position, the sealing member being spaced from the protrusions and the recesses so that they do not interfere with the action of the sealing member.
Preferably the sealing member is located at an end face of the male plug member. In this way misalignment or an act of aligning the protrusions and recesses does not damage the sealing member between the female socket member and the male plug member.
In particular the present invention is particularly designed for use with a cam lock system of the type in which the locking arrangement includes a plurality of cam members each having a lever within a respective side opening of the female socket member and a cam portion passing through one of said side openings and engaging a portion of the male plug member and each being pivotally connected to the female socket member for outward movement of the levers away from the female socket member to disengage the cam portions from the said portion of the male plug member.
Preferably the recess and/or protrusion is provided on a separate body portion which is inserted into a receptacle on the respective one of the female socket member and the male plug member to facilitate mounting of said recesses and protrusions.
Preferably the separate body portion is easily machined or otherwise configured to provide either a standard or configured coupling.
Preferably the matched protrusions and recesses are shaped and located so that they are not interchangeable with a coupling configured with a different configuration of protrusions and recesses.
Preferably the recess is formed by machining, casting or other methods in the male plug member of the coupling.
Preferably the protrusion is formed by a cast feature, a machined fastener, pressed in pin, molded or cast insert or by any other means or processes in the female socket member.
Preferably the system allows for backwards compatibility with industry standard couplings. This can be achieved by the fact that one of the female socket member and the male plug member which carries the recesses can be used in an industry standard coupling having no protrusions.
Preferably the male plug member and the female socket member both have a circular cross-section. This allows rotation as mentioned above.
However the female socket member and the male plug member can have a common unique cross sectional shape different from circular. For example the cross-sections shape can be square with rounded corners.
According to a second aspect of the invention there is provided a method of delivering a plurality of different fluids comprising:
providing for each fluid a respective delivery duct;
providing in each delivery duct a coupling as defined above;
and arranging said at least one protrusion and said at least one recess of a first one delivery duct to have a different configuration from that of a second one of the delivery ducts to prevent interchangeability of the first and second delivery ducts at the couplings.
DRAWINGS
Embodiments of the invention will be described hereinafter in conjunction with the accompanying drawings in which:
FIG. 1 is an isometric exploded view showing the new interlock coupling using flat head socket screws as the interlock protrusions.
FIG. 2 is a left end view of FIG. 1 showing the recesses and protrusions aligned to permit assembly.
FIG. 3 is an enlarged detail view of one flat head socket screw interlock protrusion aligned with a single interlock recess showing the installation clearance.
FIG. 4A is a cross section view of FIG. 2 showing assembly interference between the interlock protrusions and misaligned interlock recesses.
FIG. 4B is a cross section view of FIG. 2 showing axial assembly permitted by alignment of the interlock protrusions and interlock recesses.
FIG. 4C is a cross section view of FIG. 2 showing relative rotation of the coupling that is possible after the interlock protrusions pass by the interlock recesses.
FIG. 5A shows an end view of the male and female halves of the coupling with mating interlock protrusions and interlock recesses spaced W degrees apart. W=15 degrees.
FIG. 5B shows an end view of the male and female halves of the coupling with mating interlock protrusions and interlock recesses spaced X degrees apart. X=20 degrees.
FIG. 5C shows an end view of the male and female halves of the coupling with mating interlock protrusions and interlock recesses spaced Y degrees apart. Y=25 degrees.
FIG. 5D shows an end view of the male and female halves of the coupling with mating interlock protrusions and interlock recesses spaced Z degrees apart. Z=30 degrees.
FIG. 6 shows an isometric view of a tanker trailer with transfer hoses and related fittings connecting it to the top seal connections on underground fuel storage tanks.
FIG. 7A shows an isometric exploded view of the trailer to hose connections.
FIG. 7B shows an isometric exploded view of the hose connections to the top seal male adapters on the underground fuel storage tanks.
FIG. 8 is an isometric exploded view showing an interlock coupling using rivets with a hemispherical head as the interlock protrusions.
FIG. 9 is a left end view of FIG. 8 showing the interlock recesses and interlock protrusions aligned to permit assembly.
FIG. 10 is an enlarged detail view of one rivet interlock protrusion aligned with a single interlock recess showing the installation clearance.
FIG. 11A is a cross section view of FIG. 9 showing axial assembly permitted by alignment of the interlock protrusions and interlock recesses.
FIG. 11B is a cross section view of FIG. 9 showing relative rotation of the coupling that is possible after the interlock protrusions pass by the interlock recesses.
FIG. 12 is an isometric exploded view showing the new interlock coupling using oblong interlock protrusions as part of a molded or cast insert.
FIG. 13 is a left end view of FIG. 12 showing the interlock recesses and the inserts interlock protrusions aligned to permit assembly.
FIG. 14A is an enlarged front and left end view of a cast insert with oblong interlock protrusion spaced Z degrees apart.
FIG. 14B is an enlarged front and left end view of a cast insert with oblong interlock protrusion spaced W degrees apart.
FIG. 15A is a cross section view of FIG. 13 showing axial assembly permitted by alignment of the oblong interlock protrusions with the interlock recesses.
FIG. 15B is a cross section view of FIG. 13 showing relative rotation of the coupling that is possible after the oblong interlock protrusions passes the interlock recesses.
FIG. 16 is an isometric view showing cast in place interlock protrusions.
FIG. 17 is an isometric view showing the interlock protrusion on the male adapter and the interlock recess on the female coupling.
FIG. 18A is an isometric exploded view of an interlock coupling utilizing a rounded rectangle shape as the interlock protrusion and interlock recess.
FIG. 18B is an isometric assembled view of an interlock coupling utilizing a rounded rectangle shape as the interlock protrusion and interlock recess.
DRAWINGS - Reference Numerals
20 Male adapter of male plug member
21 Interlock recess
22 Alignment recess
23 Hose stop flange
24 Angular separation of recess
40 Female coupler of female socket member
41 Thickened body portion
42 Countersink
43 Threaded hole
44 Flat head socket screw
45 Threaded body
46 Interlock protrusion
47 Protrusion Clearance
48 Coupler Clearance
49 Interference
50 Tanker Trailer
51 API Valve
52 Valve Male Adapter
53 Tag Adapter Standard Female Coupler
54 Tag Adapter
55 Tag Adapter Configured Male Adapter
56 Dust Cap
57 Hose
60 Underground Tank - W fuel
61 Underground Tank - Z fuel
62 Top Seal Male Adapter
63 Drop Elbow Female Coupler
64 Drop Elbow
65 Drop Elbow Male Adapter
70 Rivet
71 Hemispherical End
72 Shank
73 Unformed End
74 Formed End
75 Mounting Hole
80 Insert
81 Offset Portion
82 Pocket
83 Countersink
84 Flat Head Socket Screw
85 Tapped Hole
86 Cast Protrusion
87 Cylindrical Portion
88 Trailing Ellipse Portion
89 Leading Ellipse Portion
90 Cast In Place Protrusion
91 Oblong Portion
92 Cylindrical Portion
93 Male Adapter
94 Female Coupler
95 Cast In Place Indicator
96 Oblong Portion
97 Cylindrical Portion
100 Cast Interlock Protrusion
101 Recess Grooves
102 Thickened Body Portion
110 Rectangular Female Coupler
111 Rectangular Male Adapter
500 Circular Passage
501 Circular Plug
502 Circular Plug
503 Curved Annual Groove
504 Sealing Ring
505 Sealing Surface
506 Lead-in Chamfer
507 Camlock Lever
DETAILED DESCRIPTION
FIG. 1 shows one embodiment of a nominal 4 ″ Camlock coupling with a male adapter 20 and a mating female coupler 40 . Both the male adapter and female coupler are shown with hose barb ends but it will be obvious to anyone skilled in the art that any means of connecting the coupling halves to any other device, conduit or fitting for use may be provided without departing from the spirit of the invention. Further, while a Camlock style coupling is used to illustrate the invention it will be obvious to anyone skilled in the art that other types of couplings can also benefit from this improvement. The basic form, fit and function of the coupling is disclosed in U.S. Pat. No. 2,518,026 but with the following improvements;
One or more interlock recesses 21 in the male adapter 20 interlock with one or more interlock protrusions 46 in the female coupler 40 .
A ball nose milling cutter can be used to mill slots that form the recesses 21 . Various other processes such as casting or forming can also be used to create the recesses. The recess can be any shape found to simplify manufacturing, improve assembly and prevent damage to sealing surfaces.
The protrusion 46 is formed by machining or turning a hemispherical end 46 on the end of the fully threaded body 45 of standard 8 mm metric flat head socket screw 44 . The protrusion can be any shape found to simplify manufacturing, improve assembly and prevent damage to sealing surfaces.
The female coupler 40 is cast with a thickened body portion 41 that is drilled and tapped with metric 8 mm threaded holes 43 that are countersunk 42 to accept the flat head socket screw 44 with hemispherical interlock protrusion 46 .
A flat head socket screw was selected to provide a flush final assembly 40 that would help protect an otherwise protruding fastener head from damage or potential handling injuries. However any type of fastener, pressed in pin, rivet, cast profile or insert with a cast or formed profile could be used in place of the flat head socket screw.
Two Recesses 21 and two protrusions 46 are arranged with an angular separation 24 as shown in FIG. 2 . The same angular separation is repeated on the opposite side of the coupling to provide symmetry and a balanced feel when assembling the coupling.
A virtually infinite number of symmetrical and asymmetrical angular arrangements of the interlock protrusions 46 and interlock recesses 21 are possible.
The goal is to configure sets of mutually exclusive arrangements of the interlocking protrusions and recesses so that only like configured coupling halves will fit with each other.
The recess 21 should provide a clearance fit 47 , with a typical value of approximately 0.015″ for the protrusion 46 as shown in FIG. 3 so as to allow easy assembly and disassembly of the coupling. The clearance fit 47 will be similar to the typical clearance fit 48 between the mating circular plug of the male adapter 501 & 502 and the circular passage of the female coupler 500 .
FIG. 4A shows a cross section of FIG. 2 through two opposing protrusions 46 with male adapter recesses 21 misaligned so as to prevent assembly of the coupling due to interference 49 between the protrusion 46 and the lead-in chamfer 506 on the male adapter. FIG. 4A further illustrates that the interference 49 contacts the lead-in chamfer 506 of the male adapter 20 thereby protecting the sealing surface 505 from contact with the interlock protrusion to prevent potential damage to the sealing surface 505 .
FIG. 4B shows a cross section of FIG. 2 through two opposing interlock protrusions 46 and interlock recesses 21 aligned to permit the coupling halves to interlock with each other during assembly.
FIG. 4C shows a cross section of FIG. 2 through two opposing protrusions 46 and recesses 21 after the recess and protrusion have bypassed each other and the leading end of the sealing surface 505 rests on the sealing ring 504 . The protrusion 46 is located within the curved annual groove 503 of the male adapter. The coupling halves are free to rotate relative to each other prior to applying the Camlock levers 507 that are used to clamp and seal the coupling together.
Visible alignment recesses 22 are machined in the male adapter hose stop flange 23 and aligned with the recesses 21 . This provides a visual reference between the angular spacing of the screws 44 on the female coupler and the male adapter for rotating and aligning the coupling halves prior to assembly or disassembly. Other connections, conduits and fittings attached to the male adapter could have similar alignment marks punched, scribed, machined, cast or formed to provide a similar visual alignment function.
FIGS. 5A, 5B, 5C and 5D show an example of four unique angular configurations (W, X, Y & Z respectively) that can only mate with another fitting with the same angular configuration. W configured female couplers only mate with W configured male adapters. W configured fittings will not mate with fittings configured with X, Y or Z angular configurations.
Where required any standard female coupler, without protrusions 46 , can still mate with any configured male adapter with recesses 21 . This allows for backward compatibility with standard fittings where desired or required.
FIG. 6 shows one example of a system of fittings and hose used to unload fuel at gas stations. Many other systems of fittings and hose are also used to load and unload tanker trailers and can be adapted to use a configured interlock coupling disclosed here-in. The tanker trailer 50 will be parked near to the underground fuel storage tanks 60 and 61 as shown. The tanker trailer 50 is divided into separate compartments that can carry different fuels such as Diesel, Premium, Regular and Ethanol blends in a single delivery to a gas station. Similarly, a typical gas station has multiple underground fuel storage tanks 60 , 61 etc. that can receive any or all of these fuels from a single tanker trailer delivery.
The industry currently relies on tagging procedures and color coding systems to help prevent incorrect connections between the trailer FIG. 7A and the underground storage tank FIG. 7B . Even with procedures and systems in place it is not uncommon for mixes or crossovers to occur. A premium gasoline and regular gasoline crossover will result in a costly downgrade of the premium fuel along with the time and expense to pump the downgrade into the regular grade storage tank. A diesel and gasoline mix is far more serious and expensive to rectify since the fuel is no longer useable as either gasoline or diesel and must be pumped out of the storage tank and disposed of. Diesel and gasoline crossovers that end up in vehicles can cause severe damage to fuel systems and engines and lead to expensive repairs along with a loss of reputation in the marketplace for the oil company that can result in further lost revenue. Mixes can also result in motorist and boaters becoming stranded with engine failure which can be a serious safety issue and a potential liability concern for Oil Companies.
FIG. 7A shows a tanker trailer 50 configured with four API valves 51 each connected to a separate fuel compartment in the trailer. The API valve 51 remains attached to the trailer 50 during loading and unloading of fuel. The ends of the API valves 51 terminate with a standard male adapter 52 . A “standard” male adapter or female coupler does not have interlock recesses or interlock protrusions. The four tag adapters 54 have a standard female coupler end 53 . The male adapter end 55 of the four tag adapters 54 have interlock recesses 55 W, 55 X, 55 Y and 55 Z spaced W, X, Y and Z degrees apart. See FIG. 5A through FIG. 5D for end views of these configurations. Each angular spacing W, X, Y and Z represents in this case a different fuel such as Diesel, Premium, Regular and Ethanol carried by the trailer 50 . It is understood that the valve and fitting configuration shown in FIG. 7A is only one of many possible configurations. For instance the trailer 50 could be configured with additional or fewer fuel carrying compartments with corresponding terminating API valves 51 . The trailer can also carry the same fuel in more than one compartment and in this case the same tag adapter configuration would be used on the two API valves communicating with the two compartments carrying the same fuel.
The standard female coupler 53 of the tag adapter 54 is attached and preferably locked to the API valve 51 at the fuel depot to tag which fuel is contained in a given compartment and to ensure that this tag cannot be accidentally removed or tampered with.
The dust cap 56 is installed during transport and is a standard female coupler that can be used on the ends 55 of all the configured tag adapters 54 .
The tag adapter 54 with its particular recess configuration 55 W, 55 X, 55 Y and 55 Z acts as a tagging system to identify the fuel stored in a particular compartment of the trailer. Therefore manual tagging and color coding procedures could be eliminated with this system or used together with this system to act as an additional visual reference and barrier for preventing crossovers.
The tag adapter 54 works like a key that only permits like configured fittings and accessories to interlock with each other.
In FIG. 7A the left most tag adapter 54 labeled W is connected as shown in FIG. 7B to tank adapter 62 with configured recessed end 62 W that communicates with an underground storage tank 60 through a hose 57 with female hose couplers 40 on both ends configured with interlock protrusions 46 W on both ends and a drop elbow fitting 64 with a female coupler configured with interlock protrusions 63 W and a male adapter configured with recesses 65 W.
Although not illustrated a similar system of configured fittings can be used to bottom load trailers at the fuel depot to ensure the correct fuel is loaded into the correct compartment of the trailer.
The W, X, Y, Z recess and protrusion configurations and any other required configurations would be standardized industry wide for particular fuels. With a standard in place the first step would be to replace gas station tank male adapters with male adapters configured for a particular fuel. Since the system is backwards compatible with standard Camlock fittings there will be no interruption in fuel delivery service if tanker trailers are still operating without configured fittings and accessories. Tanker trailers typically carry multiple sets of hoses and fittings, one set for each fuel delivered. Therefore the quantity of hose and fittings is the same only now they are configured for a particular fuel. There is also no appreciable change in procedures for unloading fuel except that there is now positive feedback when a connection is attempted between say a Diesel and Premium fitting. Since configured fittings and accessories are not compatible with each other and will not physically fit together the potential for crossovers is prevented.
FIGS. 8, 9, 10, 11A, 11B show an additional embodiment that uses a rivet 70 with a hemispherical head 71 as the interlock protrusion. The shank portion 72 of the rivet 70 is installed from the inside surface 500 of the female coupler 40 through mounting holes 75 drilled through from the outside wall 506 of the female coupler right through the inside wall 500 . The end of the rivet 73 is formed with a riveting tool (not shown) to produce a formed head 74 that locks the rivet in place. Any standard or purpose built fastener can be used in place of the rivet and installed from the inside surface 500 where the head of the fastener becomes the interlock protrusion and the shank portion is threaded to accept a nut installed on the threaded shank that bears against the outside surface 506 .
Advantages of this embodiment include;
The rivet provides a semi-permanent attachment of the protruding element that will prevent easy removal or tampering.
A standard female coupler casting can be drilled to accept a rivet or fastener installed from the inside. A custom casting with a thickened body portion 41 , to facilitate a threaded hole 43 , as shown in FIG. 1 is not required.
FIGS. 12, 13, 14A, 14B, 15A, 15B show an additional embodiment that uses a cast or formed insert 80 that includes protrusions 86 that form part of the insert 80 . The female coupler casting 89 includes one or more offset portions 81 and associated pockets 82 sized to accept the insert 80 . The insert is held in place with one or more fasteners 84 . The insert 80 includes one or more tapped holes 85 and the female coupler casting includes one or more countersunk mounting holes 83 to facilitate mounting of the insert 80 to the female coupler pocket 82 with flat head socket screws 84 .
The interlock protrusion 86 is formed with a partially cylindrical protrusion 87 that tapers to an oblong elliptical shape 88 at each end. The overall cast protrusion 86 is shaped and sized to fit the annular curved groove 503 of the male adapter with clearances to provide for easy assembly, disassembly and relative rotation prior to the cam levers 507 being engaged.
Advantages of this embodiment include;
Easily interchangeable inserts that are pre-configured with different protrusion angular offsets such as the two examples shown in FIGS. 14A and 14B .
A single female coupler casting 89 can accommodate multiple different insert configurations 80 . This modular system permits female couplers to be easily configured and reconfigured by the end user as required.
Two different insert configurations (ie both 14 A and 14 B) can be installed in a single female coupler 89 to provide additional unique combinations where required.
FIG. 16 shows an additional embodiment that has interlock protrusions 90 cast directly into the female coupler casting 94 . The cast interlock protrusion 90 is shaped with a partially cylindrical protrusion 92 that tapers to an oblong or elliptical shape 91 at each end. This same shape 95 is replicated on the outside surface of the female coupler 94 with similar cylindrical protrusion 97 that tapers to oblong or elliptical ends 96 that act as a visual reference to assist with rotating and aligning the male adapter 93 and female coupler 94 .
Advantages of this embodiment include;
Both the male adapter and female couplers are purchased with specific industry standard configurations of interlock protrusions that are ready to use without any further user intervention.
Lowest cost production method for the female couplers as no additional machining or assembly is required.
FIG. 17 shows an additional embodiment that has the interlock protrusions 100 located on the male adapter and the recesses 101 located on the female coupler.
Advantages of this embodiment include;
With the protrusion moved to the male adapter and the male adapter used as the tank adapter it would prevent the connection of standard female couplers. This will further limit the possibility of a crossover since the only female coupler that with fit is one configured specifically to match this male coupler. This is different from the other embodiments that still permit backwards compatibility with standard female couplers.
The embodiment shown prevents relative rotation of the coupling halves after assembly which eliminates the requirement to align the coupling halves prior to disassembly.
FIGS. 18A, 18B show an additional embodiment of an interlock coupling that relies on a specific and unique shape such as the square with rounded corners shape used on the male adapter 111 and on the female coupler 110 . As with the protrusions and recesses used on the other embodiments a family of unique shapes can be selected, one shape for each of the various grades and types of fuels delivered. For example the square with rounded corners shape could be used for diesel, a triangle with rounded corners could be used for premium, an oval shape could be used for regular and other shapes can be used for other fuels.
Advantages of this embodiment include;
Unique and distinct shapes provide immediate visual recognition for connecting compatible couplings and accessories
With a unique and distinct shape used as the male tank adapter and also used on tanker trailer tag adapter it would prevent the connection of any other standard or distinctly shaped female couplers. This will completely eliminate the possibility of a crossover since the only female coupler and related accessories that with fit is one configured with the same shape to match this male adapter. This is different from the other embodiments that still permit backwards compatibility with standard female couplers.
The embodiment shown prevents relative rotation of the coupling halves after assembly which eliminates the requirement to align the coupling halves prior to disassembly. If rotation of a particular accessory such a drop elbow is required, a swivel connection, as is already commonly used on many types of fittings, could be provided at a suitable location between the female coupler and the male adapter ends of the drop elbow or any other fitting or accessory requiring this feature.
Summary of Embodiments Presented
The embodiments described are not meant to limit the scope of the invention but rather to illustrate just a few of the possible configurations possible within the spirit of this invention. No particular embodiment is preferred at this time as there are advantages to each embodiment presented. For instance it may be desirable to use existing fittings and accessories modified as shown in FIG. 8 to test the system with various protrusion and recess configurations, shapes and sizes before committing to an industry standard and the expense of custom castings and mass production. After industry acceptance and standardization it will be desirable to minimize the costs of the various fittings and accessories so multiple castings with the specific recesses and protrusions for each fuel may be desirable as shown in FIG. 16 . Other embodiments such as shown in FIG. 1 and FIG. 12 allow for standardization on a single casting for both the male adapter and the female coupler that can be configured through the use of cast inserts FIG. 12 or machining specific configurations FIG. 1 .
Finally, while the example of fuel unloading at gas stations using an improved Camlock fitting to prevent crossovers is presented the invention is not limited to this industry or this style of coupling. Many industries now and in the future may have a need to prevent crossovers and will be able to make use of this improved interlock coupling and system utilizing other styles of couplings that can be adapted in the same way without departing from the spirit of the improved interlock coupling disclosed above.
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A quick-disconnect coupling such as a camlock includes a hollow male plug with an external peripheral groove and a hollow female socket defining a duct for communication of a fluid with a locking arrangement for locking the male plug in the female socket. Protrusions are provided on either an inside surface of the female socket or on an outside surface of the male plug and corresponding recesses are provided on the other with the recesses and protrusions being cooperatively shaped and arranged to allow insertion of the male plug member into the female socket member to the locking position only when at least one recess and at least one protrusion match.
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CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a division of U.S. application Ser. No. 11/730,280, filed Mar. 30, 2007 now U.S. Pat. No. 7,480,476, which is a divisional of U.S. application Ser. No. 10/864,672 (now U.S. Pat. No. 7,321,744), filed Jun. 10, 2004, which is a continuation of Patent Application No. PCT/JP04/02025, filed Feb. 20, 2004, and claims priority to Japanese Patent Application No. 2004-004668 filed Jan. 9, 2004, and Japanese Patent Application Nos. 2003-052658 and 2003-054478 filed Feb. 28, 2003. The entire contents of each of these documents are incorporated herein by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a developer container which accommodates a developer, and to a developer supplying device which supplies a developer, such as toner, to a developer receiving device, such as a visible image formation unit that forms a visible image on an image supporting medium such as a photoconductor. Moreover, the present invention relates to an image forming apparatus, such as a copier, a printer, a facsimile, etc., which uses the developer container and the developer supplying device.
2. Description of the Related Art
Conventionally, it is known that a cylindrical toner bottle is used as a developer container which is provided in a developer supplying device which supplies a developer, such as toner, to a developing device of an image forming apparatus, such as a copier, a printer, a facsimile.
The toner bottle is provided with a spiral projection disposed in the inner wall of the toner bottle and a bottle gear for rotating the toner bottle. The developer, such as toner, inside the toner bottle is discharged from the toner bottle by rotation of the toner bottle through the gear, and the discharged developer is conveyed to the developing device, so that the developing device is supplied with the developer.
However, even if the toner guide is provided in the developer container in which the gear is provided on the side surface of the developer container near the opening of the toner, there is the problem that discharging of the toner by the rotation of the developer container in the circumferential direction thereof may not be performed smoothly.
The bottle gear provided in the toner bottle as the developer container is configured in a ring-like formation in which a central opening is formed on the inside peripheral surface of the gear. When the diameter of the opening is smaller than the inner diameter of the inner wall of the toner bottle at the position where the gear is provided, the inner wall of the toner bottle is provided with a raised portion which is raised from the position of the bottle gear.
Since the toner bottle is laid horizontally in the image forming apparatus, if the raised portion of the inner wall is at the intermediate portion before the position where the toner inside the bottle arrives at the toner outlet, the toner inside the bottle cannot be transferred beyond the raised portion and cannot reach the toner outlet. For this reason, there is the case in which discharging of the toner may be performed smoothly.
A conceivable method to overcome the problem is to make the diameter of the opening of the bottle gear larger than the inner diameter of the inner wall of the toner bottle. For example, the diameter of the opening of the gear may be made to equal to the inner diameter of the inner wall of the toner bottle.
However, in such a case, there is a certain amount of distance from the opening of the gear to the dedendum of the gear teeth, and the gear tooth will project from the peripheral side surface of the toner bottle in the direction normal to the bottle peripheral surface. Then, the image forming apparatus in which the toner bottle is provided will require the space for accommodating the bottle gear rotatably inside the apparatus, in addition to the space for accommodating the toner bottle inside the apparatus. This makes the image forming apparatus to be enlarged in size.
Therefore, in order for the miniaturization of the image forming apparatus, it is desirable that toner supply can be performed smoothly even when the diameter of the opening of the bottle gear is smaller than the inner diameter of the inner wall of the toner bottle.
Japanese Laid-Open Patent Application Nos. 10-063084, 07-020705 and 09-251240 disclose some toner bottles which are a developer container and provided to be detachably attached to the toner supply device of the main part of the image forming apparatus in the longitudinal direction of the apparatus. In the conventional devices of the above-mentioned documents, the toner bottle is detachably attached from the front side of the image forming apparatus, or the cartridge accommodating the toner bottle therein is detachably attached from the front side of the apparatus main part.
Moreover, in order to carry out the rotation drive of the toner bottle, the conventional devices of the above-mentioned documents have the following mechanisms.
In the device of Japanese Laid-Open Patent Application No. 10-063084, the bottom of the toner bottle is connected with the drive unit provided on the rear side plate of the apparatus main part so that the rotation drive of the toner bottle is carried out.
In the device of Japanese Laid-Open Patent Application No. 07-020705, the engagement unit provided near the shoulder of the toner bottle is connected with the drive unit provided in the apparatus main part, so that the rotation drive of the toner bottle is carried out.
In the device of Japanese Laid-Open Patent Application No. 09-251240, the bottle gear is provided near an end of the toner bottle opposite to another end of the toner bottle where the toner outlet is formed, and the bottle gear is engaged with the drive gear so that the rotation drive of the toner bottle is carried out.
As described above, in the devices of the above-mentioned documents, the toner bottle or the cartridge which accommodates the toner bottle is detachably attached from the front side of the apparatus main part, and the operation space in the case of the attachment and detachment will be needed at the front side of the apparatus, and it will be necessary to take many installation area of the apparatus.
Moreover, in the composition in which the developer container is detachably attached from the front side of the apparatus main part, the operator has to lean over in front of the apparatus, and has to perform the toner bottle exchange, or in order to detach the used developer container from the apparatus main part in the state where the toner outlet opened, the operator has to consider so that the remaining toner may not leak from the opening and the front of the apparatus may not be polluted.
From the above reasons, the attachment/detachment method of the developer container from the front side of the apparatus must be taken into consideration.
Moreover, it is demanded that the operator can easily perform developer container exchange, with the spread of color image forming apparatuses in recent years, and it is necessary to make the attachment/detachment operation of the developer container easy.
If the developer container can be detachably attached from the upper part of the main part of the apparatus apart from the above conventional method of detaching and attaching the developer containers from the front of the apparatus, what is necessary is opening the top cover of the main part of the apparatus in the case of developer container attachment and detachment, and exchange removing the developer container of the required color from the upper part, and just coming to set the new developer container.
Therefore, it is no longer necessary to take the operation space in the installation area of the apparatus as in the conventional method of attachment and detachment of the developer container from the front of the apparatus, and it is possible to reduce the installation area.
Moreover, since attachment/detachment operation can be performed being able to exchange the developer container, with the operator standing, and looking at the developer container and it is easy to protect that the toner from developer container opening begins to leak, and the attachment/detachment operation becomes easy.
From the above reason, the developer container attachment and detachment from the upper part of the apparatus main part can also make the operation easy, and it is possible to reduce the installation area of the apparatus. This is desirable.
Moreover, although the miniaturization of the apparatus is being called for in recent years, in order to miniaturize the apparatus, what is taken into consideration also about the configuration of the drive unit which drives the developer container is searched for.
However, in the device of Japanese Laid-Open Patent Application No. 10-063084, the engagement unit with the main part side drive unit of the apparatus in the toner bottle is provided in the direction end of the toner bottle length, and the position in which the drive unit is formed consists of this bottle the back side further in the direction of the length of the toner bottle.
For this reason, the total length of the depth of the drive unit and the length of the toner bottle in the longitudinal direction will be needed for the depth of the apparatus, and the length of the apparatus will be enlarged.
If the peripheral side surface of the toner bottle is adjoined as in the devices of Japanese Laid-Open Patent Application Nos. 07-020705 and 09-251240 and the input unit of driving force is provided, the necessity of arranging in order and providing the drive unit and the bottle in the direction of the bottle length will be lost, and it is possible to prevent enlargement of the depth of the apparatus. The apparatus can be miniaturized, and it is desirable.
If the input unit of driving force is provided in the side surfaces other than the direction end of the length of the developer container from the upper part of the apparatus while enabling the developer container attachment/detachment from the apparatus upper part, the advantages of space saving at the time of attachment and detachment, improvement in the attachment/detachment operation, and many further called the miniaturization of the apparatus can be obtained, and the usefulness is high.
Moreover, in the conventional device, the developer container, such as the toner bottle, is provided so that the developer container is detachably attached to a container mounting unit of the developer supplying device.
In the conventional device, after removing the used developer container which is empty with consumption of the developer from the container mounting unit, the developer can be replaced with the image forming apparatus to the developer receiving device, such as the visible image formation unit, by setting the new developer container.
In the above developer supplying device, the developer in the developer container is moved to the outlet as such a developer supplying device using conveyance drive components, such as the agitator provided in the main part of the container, as disclosed in Japanese Laid-Open Patent Application No. 2002-357945.
Moreover, the spiral projection is formed in the inner wall of the elongated main part of the container which accommodates the developer inside, and the internal developer is moved to the outlet by rotating the main part of the container so that the central axis extending in the longitudinal direction may turn into the center-of-rotation axis, as disclosed in Japanese Laid-Open Patent Application No. 2000-338758.
In the developer supplying device of Japanese Laid-Open Patent Application No. 2000-338758, the spiral projection formed in the wall in the main part of the container is moved with the rotation of the main part of the container, and the internal developer is moved to the outlet by the movement of the spiral projection.
Similar to the developer supplying device of Japanese Laid-Open Patent Application No. 2000-338758, the applicant to which the present invention is assigned has proposed the image forming apparatus equipped with the developer supplying device in which the main part of the container is rotated, and the internal developer is moved to the outlet by the rotation of the container main part, as disclosed in Japanese Patent Application No. 2002-276466.
In the above-mentioned image forming apparatus, the toner bottle as shown in FIG. 32A , which is a developer container, is used. In the toner bottle 632 of FIG. 32A , the cap portion 634 , which is a rotation unit, is provided at the leading end of the main part 633 of the toner bottle 632 .
Moreover, the toner outlet (not shown) opens to a part of the peripheral side surface of the cap portion 634 , and this toner outlet is closed with the shutter 636 in the state of FIG. 32A . This shutter 636 is attached to the peripheral side surface of the cap portion 634 so that it is slidable on the peripheral side surface of the cap portion 634 .
Moreover, in order to allow the cap portion 634 to be rotated around the central axis of the cap portion 634 , the handle 635 which is taken by the operator is formed integrally with the cap portion 634 . When placing the toner bottle 632 on the bottle holder 631 indicated by the dotted line in FIG. 32A , the toner bottle 632 is laid on the bottle holder 631 as in the state of illustration.
If the direction of the arrow N in FIG. 32A is made to rotate the handle 635 , although the cap portion 634 constituted by the handle 635 and one rotates, as for the shutter 636 , in contact with shutter stop unit 631 a of the bottle holder 631 , rotation will be prevented from this state.
Thereby, the shutter 636 carries out the slide transfer relatively to the peripheral side surface of the cap portion 634 by the rotation, and the toner outlet is moved so that it faces the bottle holder 631 in the downward perpendicular direction (the underside of FIG. 32A ). Therefore, the toner outlet which is in the closed state by the shutter 636 is opened to the perpendicular direction down side.
On the other hand, when removing the toner bottle 632 from the bottle holder 631 , the handle 635 is rotated in the reverse direction opposite to the direction of the arrow N in FIG. 32A .
Thereby, the toner outlet also transfers for reverse with rotation of the cap portion 634 with the arrow N in FIG. 32A , and the shutter 636 carries out the slide transfer relatively to the peripheral side surface of cap portion 34 Y according to the energization force by the energization unit (not shown).
And the toner outlet is closed by the shutter 636 . Therefore, in case the toner bottle 632 is dealt with, the toner does not begin to leak from the toner outlet.
FIG. 32B is a cross-sectional view of the circumference of the cap portion 634 taken along the central axis O of the toner bottle 632 and passing through the toner outlet.
As shown in FIG. 32B , as the cap portion 634 is inserted in the portion of the opening C of the main part 633 of the bottle, it is attached to the main part 633 of the bottle.
And when the toner bottle 632 is set to the bottle holder 631 , this cap portion is locked to the bottle holder. Therefore, when it is engaged with the drive gear of the drive motor and the rotation driving force of the drive motor is transmitted to the bottle main part 633 via the bottle gear 637 , the main part 633 of the bottle is rotated in the direction of the arrow Q in FIG. 32A with the friction sliding of the bottle gear 637 with the cap portion 634 .
However, the lock of the cap portion 634 to the bottle holder 631 may be made with a comparatively weak force in consideration of the ease of operation of the operator who operates the handle 635 of the cap portion 634 .
Therefore, if the frictional force between the rotating main part 633 of the bottle and the cap portion 634 exceeds the force to lock the cap portion 634 , the cap portion 634 will rotate with the rotation of the main part 633 of the bottle.
Consequently, the toner outlet opened to the perpendicular direction down side is also moved to the direction of the arrow Q in FIG. 32A , and will be in the closed state by the shutter 636 . Then, even if the main part 633 of the bottle is rotated to perform toner supply operation, there is the problem that the situation in which toner supply is not actually performed arises.
In addition, if the direction (the direction of the arrow Q in FIG. 32A ) of rotation of the main part 633 of the bottle is reversed, the toner outlet will not be closed according to the friction between the main part 633 of the bottle and the cap portion 634 , and the above-mentioned problem does not occur.
However, it is necessary to reverse the direction of the rotation drive of the main part 633 of the bottle in this case and the design change relevant to the composition of the toner feeder and the whole image forming apparatus is obliged, and it may be difficult to adopt such composition.
Moreover, since the direction of the spiral toner guide 633 a currently formed in the inner wall of the main part 633 of the bottle in this case must be reversed by the design change, there is also the disadvantage that it is impossible to use the toner bottle before design change.
On the other hand, if the direction (the direction of the arrow N in FIG. 32A ) in which the shutter 636 is displaced relative to the cap portion 634 when changing the toner outlet to the closed state is reversed, the above-mentioned problem does not occur.
However, it will be necessary to change the composition of the toner feeder relevant to the shutter in this case, and it may be difficult to adopt such composition.
Moreover, since the cap portion 634 will also be subjected to the composition change in this case, there is also the disadvantage that it is impossible to use the toner bottle before design change.
Moreover, if the toner bottle 632 is provided such that the cap portion (rotation unit) 634 may be rotated in the first direction (which is opposite to the second direction in which the shutter 636 opens the toner outlet), the operator may rotate, when attaching the toner bottle 632 to the bottle holder 631 , the cap portion (rotation unit) 634 in the first direction accidentally. In this case, there is the possibility of the incorrect setting of the cap portion 634 .
Moreover, if the toner bottle 632 is provided such that the cap portion 634 may be rotated further after the toner outlet is opened by the shutter 636 through the operator's proper rotation of the cap portion 634 in the second direction when attaching the toner bottle 632 to the bottle holder 631 , the cap portion 634 will be excessively rotated. In this case, there is the possibility of the falling out of the shutter 636 may arise.
SUMMARY OF THE INVENTION
In order to overcome the above-described problems, the first aspect of the present invention is to provide an improved developer container for use in an image forming apparatus in which toner supply can be carried out smoothly, while realizing improvement in the attachment/detachment operation of the developer container to the main part of the image forming apparatus, and the miniaturization of the image forming apparatus.
The second aspect of the present invention is to provide a developer container and a developer supplying device using the developer container, which can prevent the plugging of the toner outlet by the shutter with the rotation of the container main part, while making the design change unnecessary and avoiding the above-described problems.
The third aspect of the present invention is to provide a developer container for use in an image forming apparatus in which incorrect setting of the developer container can be prevented and the problem of the excessive rotation of the cap portion arising when the shutter is caused to open the toner outlet can be overcome.
The above-mentioned objects of the present invention are achieved by a cylindrical developer container which has a main part accommodating a developer therein and is detachably attached to an image forming apparatus, the developer container comprising: an outlet provided at a side of the developer container to discharge the developer in the developer container; an input unit provided adjacent to the outlet and having a small-diameter portion an inside diameter of which is smaller than a diameter of the container main part, wherein, when the container is attached to the image forming apparatus, the input unit is engaged with a drive motor of the image forming apparatus to receive a rotating force of the drive motor; and a developer guiding unit which causes the developer inside the developer container to be moved to the outlet beyond the small-diameter portion of the input unit by rotation of the developer container.
The above-mentioned objects of the present invention are achieved by an image forming apparatus comprising: an image supporting medium; a visible image formation unit forming a visible image on the image supporting medium; a developer supplying device supplying a developer to the visible image formation unit; a developer container; a container mounting unit to which the developer container is attached; and a drive unit rotating the developer container in a circumferential direction of the developer container, wherein the developer container comprises: a main part accommodating the developer therein; an outlet provided at a side of the developer container to discharge the developer in the developer container; an input unit provided adjacent to the outlet and having a small-diameter portion an inside diameter of which is smaller than a diameter of the container main part, wherein, when the container is attached to the image forming apparatus, the input unit is engaged with a drive motor of the image forming apparatus to receive a rotating force of the drive motor; and a developer guiding unit which causes the developer inside the developer container to be moved to the outlet beyond the small-diameter portion of the input unit by rotation of the developer container.
The above-mentioned objects of the present invention are achieved by a developer supplying device which includes a developer container having a main part accommodating a developer therein and having an opening at an end surface of the container main part, and a rotation unit attached to the container main part to cover the opening and having an outlet provided on a circumferential surface of the rotation unit and communicating with the opening, wherein the developer in the container main part is moved to the opening and discharged from the outlet when the container main part, attached to a container mounting unit, is rotated around a longitudinal axis of the container main part, so that the developer supplying device supplies the developer discharged from the developer container to a developer receiving device, wherein the developer container comprises a shutter provided on the rotation unit to open or close the outlet by a movement of the shutter relative to the rotation unit in a rotation direction of the container main part, the developer supplying device is provided to apply a frictional force to the shutter or the rotation unit to cause the relative movement of the shutter and the rotation unit in a direction to close the outlet during the rotation of the container main part, and the developer supplying device comprises a regulation unit regulating the relative movement of the shutter and the rotation unit in the direction to close the outlet, by using the frictional force with the container main part when the container main part is rotated to discharge the developer from the outlet.
The above-mentioned objects of the present invention are achieved by an image forming apparatus comprising: a visible image formation unit forming a visible image on an image supporting medium; and a developer supplying device which includes a developer container having a main part accommodating a developer therein and having an opening at an end surface of the container main part, and a rotation unit attached to the container main part to cover the opening and having an outlet provided on a circumferential surface of the rotation unit and communicating with the opening, wherein the developer in the container main part is moved to the opening and discharged from the outlet when the container main part, attached to a container mounting unit, is rotated around a longitudinal axis of the container main part, so that the developer supplying device supplies the developer discharged from the developer container to a developer receiving device of the visible image formation unit, wherein the developer container comprises a shutter provided on the rotation unit to open or close the outlet by a movement of the shutter relative to the rotation unit in a rotation direction of the container main part, the developer supplying device is provided to apply a frictional force to the shutter or the rotation unit to cause the relative movement of the shutter and the rotation unit in a direction to close the outlet during the rotation of the container main part, and the developer supplying device comprises a regulation unit regulating the relative movement of the shutter and the rotation unit in the direction to close the outlet, by using the frictional force with the container main part when the container main part is rotated to discharge the developer from the outlet.
The above-mentioned objects of the present invention are achieved by a cylindrical developer container which has a main part accommodating a developer therein and is detachably attached to an image forming apparatus, the developer container comprising: a rotation unit which is rotatable relative to the container main part; an outlet provided on the rotation unit to discharge the developer in the developer container; a shutter provided on the rotation unit to open or close the outlet by rotation of the rotation unit when the container is attached to the image forming apparatus; and an engagement unit provided on a peripheral side portion of the rotation unit, the engagement unit being engaged with the image forming apparatus to prevent rotation of the rotation unit.
The above-mentioned objects of the present invention are achieved by a cylindrical developer container which has a main part accommodating a developer therein and is detachably attached to an image forming apparatus, the developer container comprising: a rotation unit which is rotatable relative to the container main part; an outlet provided on the rotation unit to discharge the developer from the container; a shutter provided on the rotation unit to open or close the outlet by rotation of the rotation unit; a first rotation preventing unit provided on the rotation unit to prevent the rotation unit from being rotated in a first direction when the container is attached to the image forming apparatus; and a second rotation preventing unit provided on the rotation unit to prevent the rotation unit from being rotated further in a second direction opposite to the first direction after the rotation unit is rotated in the second direction by the attachment of the container to the image forming apparatus and the shutter is caused to open the outlet by the rotation of the rotation unit.
According to the developer container of the present invention, it is possible to provide an image forming apparatus in which toner supply can be carried out smoothly, realizing improvement in the attachment/detachment operation of the developer container to the image forming apparatus, and the miniaturization of the image forming apparatus.
Moreover, according to the image forming apparatus of the present invention, it is possible to perform toner supply smoothly, realizing improvement in the attachment/detachment operation of the developer container to the image forming apparatus, and the miniaturization of the image forming apparatus.
Moreover, according to the developer supplying device and the image forming apparatus of the present invention, it is no longer necessary to carry out the design change such that the direction of rotation of the container main part is reversed, or the direction of opening and closing of the shutter in the developer container is revered, while overcoming the above-described problems. In addition, it is possible to prevent the plugging of the toner outlet by the shutter with the rotation of the container main part without causing the above-described problems.
Furthermore, according to the developer container of the present invention, it is possible to prevent the incorrect setting of the developer container and avoid the problem of the excessive rotation of the cap portion arising when the shutter is caused to open the toner outlet.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects and further features of the present invention will be apparent from the following detailed description when read in conjunction with the accompanying drawings, in which:
FIG. 1 is a cross-sectional view of a printer to which an embodiment of the developer container of the invention is applied;
FIG. 2 is an enlarged view of the Y process cartridge in a first preferred embodiment of the invention;
FIG. 3 is a perspective view of the Y toner bottle in the present embodiment;
FIG. 4 is a perspective view of the bottle holder and the toner bottles in the present embodiment;
FIG. 5 is a perspective view of the Y, M, C and K toner supply devices in the present embodiment;
FIG. 6 is a perspective view of the process cartridges and the toner supply devices;
FIG. 7A is a perspective view of an embodiment of the toner bottle in which a resin case is removed, and FIG. 7B is a front view of the toner bottle in which the resin case is removed;
FIG. 8A and FIG. 8B are side views of the toner bottle of the present embodiment;
FIG. 9 is a side view of a variation of the toner bottle in the present embodiment of the invention;
FIG. 10A and FIG. 10B are cross-sectional views of the toner bottle and the bottle holder before attachment of the bottle to the holder;
FIG. 11 is a cross-sectional view of the bottle holder to which the toner bottle is attached;
FIG. 12 is a cross-sectional view of the bottle holder with the toner bottle being rotated;
FIG. 13 is a diagram for explaining changes of the position of a drive gear to a bottle gear of the toner bottle;
FIG. 14 is a perspective view of an embodiment of the toner bottle in a second preferred embodiment of the invention;
FIG. 15 is a cross-sectional view of the toner bottle of the present embodiment;
FIG. 16 is a perspective view of the bottle holder and the toner bottles in the present embodiment;
FIG. 17A and FIG. 17B are cross-sectional views of the toner bottle and the bottle holder before attachment of the bottle to the holder;
FIG. 18 is a cross-sectional view of the bottle holder to which the toner bottle is attached;
FIG. 19 is a cross-sectional view of the bottle holder with the toner bottle being rotated;
FIG. 20A is a cross-sectional view of the toner bottle before the bottle rotation, and
FIG. 20B is a cross-sectional view of the toner bottle after the bottle rotation;
FIG. 21 is a perspective view of the Y, M, C and K toner supply devices in the present embodiment;
FIG. 22A is a cross-sectional view of the bottle holder before the open/close cover is closed, and FIG. 22B is a cross-sectional view of the bottle holder after the open/close cover is closed;
FIG. 23 is a cross-sectional view of the bottle holder when the open/close cover is closed with the toner bottle being set incorrectly;
FIG. 24 is a cross-sectional view of another embodiment of the open/close cover and the bottle holder in the second preferred embodiment of the invention;
FIG. 25A is a cross-sectional view of the bottle holder before another embodiment of the open/close cover is closed, and FIG. 25B is a cross-sectional view of the bottle holder after the open/close cover of this embodiment is closed;
FIG. 26A is a cross-sectional view of another embodiment of the toner bottle and the bottle holder after the toner bottle is attached to the bottle holder, and FIG. 26B is a cross-sectional view of the bottle holder with the toner bottle being rotated;
FIG. 27 is a cross-sectional view of another embodiment of the open/close cover and the bottle holder with the toner bottle being set incorrectly;
FIG. 28A and FIG. 28B are cross-sectional views of the open/close cover and the bottle holder before and after the open/close cover is closed;
FIG. 29A is a perspective view of another embodiment of the toner bottle in the second preferred embodiment of the invention, and FIG. 29B is a cross-sectional view of the toner bottle of the present embodiment;
FIG. 30A is a cross-sectional view of the bottle holder to which the toner bottle is attached, and FIG. 30B is a cross-sectional view of the bottle holder with the toner bottle being rotated;
FIG. 31 is a cross-sectional view of the bottle holder after the open/close cover is closed; and
FIG. 32A is a perspective view of a conventional toner bottle, and FIG. 32B is a cross-sectional view of a cap portion of the conventional toner bottle.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
A description will now be provided of the preferred embodiments of the present invention with reference to the accompanying drawings.
Hereinafter, the printer in which the electrophotographic printing method is carried out will be explained as an example of the image forming apparatus to which an embodiment (hereinafter called the first preferred embodiment) of the invention is applied. However, the present invention is not limited to the printer in the following description but applicable to another image forming apparatus. In addition, the imaging unit is explained as a process cartridge.
First, a description will be given of the composition of the printer. FIG. 1 is a cross-sectional view of the printer to which an embodiment of the developer container of the invention is applied.
The printer 100 is provided with the four process cartridges 6 Y, 6 M, 6 C, 6 K which generate the toner images of yellow, magenta, cyan, and black (which are called Y, M, C, and K toner images). The process cartridges respectively use Y, M, C and K toners which are mutually different colors as an image-forming substance, but they have the same composition and are exchanged by the new one at a time of toner replenishment.
The process cartridge 6 Y which generates the Y toner image is considered a representative example of the four process cartridges. As shown in FIG. 2 , the process cartridge 6 Y includes the drum-like photoconductor 1 Y, the drum cleaning device 2 Y, the electric discharger (not shown), and the charging device 4 Y, and the developing device 5 Y.
The process cartridge 6 Y is detachably attached to the printer 100 main part, and it is possible to exchange the parts at once.
The above-mentioned charging device 4 Y charges uniformly the surface of photoconductor 1 Y which is rotated in the clockwise rotation direction by the drive unit (not shown).
The exposure scan is carried out by the laser light L, and the surface of photoconductor 1 Y being charged uniformly supports the electrostatic latent image by it.
The electrostatic latent image of the Y is developed by developing-device 5 Y which uses Y toner at Y toner image. And the middle transfer is carried out on the middle transfer belt 8 . The drum cleaning device 2 Y removes the toner which remained on the photoconductor 1 Y surface after passing through the middle transfer process.
Moreover, the electric discharger discharges the residual charge of photoconductor 1 Y after cleaning. The surface of the photoconductor 1 Y is initialized by the electric discharge, and it is prepared for the following image formation.
Also in the other process cartridges 6 M, 6 C and 6 K, the M, C and K toner images are similarly formed on the photoconductors 1 M, 1 C, and 1 K, and the middle transfer is carried out on the middle transfer belt 8 .
The exposure device 7 is arranged in each of the lower parts of the process cartridges 6 Y, 6 M, 6 C and 6 K shown in FIG. 1 . The exposure device 7 which acts as the latent image formation unit irradiates each photoconductor in the process cartridges 6 Y, 6 M, 6 C and 6 K, with the laser light L emitted based on image information. The exposure of each photoconductor to the laser light L is carried out. Of the exposure, the electrostatic latent images for Y, M, C, and K are formed on the photoconductors 1 Y, 1 M, 1 C and 1 K.
In addition, the exposure device 7 irradiates the photoconductor through two or more optical lenses and mirrors, scanning the laser light (L) emitted from the light source by the polygon mirror which is rotated through the rotation drive motor.
The paper feed unit including the paper accommodating cassette 26 in which the feed roller 27 and the resist roller pair 28 are built is arranged in the bottom portion of the exposure device 7 . In the paper accommodating cassette 26 , a number of copy sheets P are contained, and the feed roller 27 is in contact with the copy sheet P on the top of the number of copy sheets.
When the feed roller 27 is rotated counterclockwise by the drive unit (not shown), the top copy sheet P is conveyed to the position between the rollers of the resist roller pair 28 . Although the resist roller pair 28 carries out the rotation drive of the rollers to clamp the copy sheet P, the rotation drive is stopped immediately. And the copy sheet P is transferred to the secondary transfer nip by the resist roller pair 28 at a suitable timing.
In the above-mentioned paper feed unit, a combination of the feed roller 27 and the resist roller pair 28 (the timing roller pair) is used to constitute the conveyance unit. This conveyance unit conveys the copy sheet P from the paper accommodating cassette 26 to the secondary transfer nip.
The middle transfer unit 15 which carries out the middle image transfer with the endless middle transfer belt 8 (the middle transfer medium) is arranged at the upper part of each of the process cartridges 6 Y, 6 M, 6 C and 6 K. This middle transfer unit 15 is provided with the four primary transfer bias rollers 9 Y, 9 M, 9 C and 9 K, the cleaning devices 10 , and the middle transfer belt 8 .
Moreover, the middle transfer unit 15 includes the secondary transfer backup roller 12 , the cleaning backup roller 13 , the tension roller 14 , etc. With the counterclockwise rotation of the middle transfer belt 8 , the endless transfer is carried out by the rotation drive of at least one roller of these three rollers.
The primary transfer bias rollers 9 Y, 9 M, 9 C and 9 K put the middle transfer belt 8 which carries out the endless transfer in this way between the photoconductors 1 Y, 1 M, 1 C and 1 K, and form the primary transfer nip, respectively. In this transfer, the toner impresses the transfer bias of the reversed polarity (for example, plus) to the back surface (the inner surface of the loop) of the middle transfer belt 8 . All the rollers except the primary transfer bias rollers 9 Y, 9 M, 9 C and 9 K are grounded electrically.
With the endless transfer, the middle transfer belt 8 is the process which passes the primary transfer nip for Y, M, C, and K one by one, and the photoconductors 1 Y, 1 M, 1 C and 1 , Y, M and C on K, and K toner image pile it up, and it is transferred the first order. Thereby, the 4 color superimposed toner image (called the 4 color toner image) is formed on the middle transfer belt 8 .
The above-mentioned secondary transfer backup roller 12 puts the middle transfer belt 8 between the secondary transfer rollers 19 , and forms the secondary transfer nip in it. The 4 color toner image formed on the middle transfer belt 8 is transferred to the copy sheet P by the secondary transfer nip. The remaining toner which is not transferred to the copy sheet P adheres to the middle transfer belt 8 after passing the secondary transfer nip. The remaining toner is cleaned off by the cleaning device 10 .
In the secondary transfer nip, it is inserted between the middle transfer belts 8 and the secondary transfer rollers 19 in which the copy sheet P carries out the surface migration to the forward direction, and the above-mentioned resist roller pair 28 side is conveyed in the opposite direction. In case the copy sheet P sent out from the secondary transfer nip passes through between the rollers of the fixing device 20 , the heat and the pressure are fixed to the 4 color toner image transferred by the surface.
Then, the copy sheet P is passed through the rollers of the ejection roller pair 29 , and ejected to the outside of the printer. The stack section 30 is provided on the upper surface of the main part of the printer. The copy sheet P ejected from the ejection roller pair 29 outside the printer is stacked on the stack section 30 one by one.
A description will be given of the composition of the developing device 5 Y in the above-mentioned process cartridge 6 Y.
The developing device 5 Y in which the magnetic field generating unit is provided is equipped with the development sleeve 51 Y and the doctor 52 Y. The doctor 52 Y is a developer regulating member which regulates the thickness of the developer supported and conveyed on the development sleeve 51 Y. The development sleeve 51 Y is a developer support which supports the two-component developer, containing the toner and the magnetic powder, on its surface and conveys the same.
The first axis side developer accommodating portion 53 Y which accommodates the developer regulated by the doctor 52 Y, without being conveyed to the photoconductor 1 Y and the development region which countered is formed in the developer conveyance direction upstream side of the doctor 52 Y.
Moreover, at the portion adjacent to the first axis side developer accommodating portion 53 Y, the second axis side developer accommodating portion 54 Y to which the toner is supplied is formed. The two developer conveyance screws 55 Y for carrying out agitating and conveyance of the developer is provided in each of the first axis side developer accommodating portion 53 Y and the second axis side developer accommodating portion 54 Y, respectively.
Next, a description will be given of operation of the developing device.
In the above-mentioned developing-device 5 Y, the developer layer is formed on the development sleeve 51 Y. Moreover, the second axis side of the developer conveyance screws 55 Y is supplied with the toner, the agitating and conveyance is carried out, and the toner is mixed into the developer.
The mixing of the toner is performed so that the concentration of the toner in the developer falls within a range of a predetermined toner concentration. The toner incorporated in the developer is charged by the frictional charging with the carrier. The developer containing the charged toner is supplied to the surface of the development sleeve 51 Y which has the magnetic pole inside, and is supported by the magnetic force. The developer layer supported on the development sleeve 51 Y is conveyed in the direction indicated by the arrow in FIG. 2 with the rotation of the development sleeve 51 Y.
After the thickness of the developer layer is regulated by the doctor 52 Y, it is conveyed to the development region which counters the photoconductor 1 Y. In the development region, the development based on the latent image formed on the photoconductor 1 Y is performed. The remaining developer on the development sleeve 51 Y is conveyed to the upstream portion in the developer conveyance direction of the first axis side developer accommodating portion 53 Y with the rotation of development sleeve 51 Y.
As previously described with reference to FIG. 1 , the bottle holder 31 is arranged between the middle transfer unit 15 and the stack unit 30 which is provided at the upward portion of the middle transfer unit 15 . The bottle holder 31 accommodates the Y, M, C, K toner bottles 32 Y, 32 M, 32 C, 32 K which are the developer containers which accommodate the Y, M, C, K toners therein.
The toner bottles 32 Y, 32 M, 32 C and 32 K are arranged on the bottle holder 31 so that they are stacked from the top. The Y, M, C, K toners in the toner bottles 32 Y, 32 M, 32 C, 32 K are suitably supplied to the developing devices of the process cartridges 6 Y, 6 M, 6 C, 6 K by the toner supply devices, respectively.
The toner bottles 32 Y, 32 M, 32 C, 32 K can be attached to and detached from the main part of the printer 100 independently from the process cartridge 6 Y, 6 M, 6 C, 6 K, respectively.
FIG. 3 is a perspective view of the toner bottle 32 Y in the present embodiment. FIG. 4 is a perspective view of the bottle holder 31 to which the toner bottles 32 Y, 32 M, 32 C are attached when the toner bottle 32 K is further attached.
As shown in FIG. 3 , the leading end of the main part 33 Y of the toner bottle 32 Y is provided with the cap portion 34 Y which is a rotation unit which can be rotated relative to the main part 33 Y of the toner bottle 32 Y. Moreover, the handle 35 Y is formed integrally with the cap portion 34 Y. Moreover, the bottle gear 37 Y, which is the input gear used as the input unit integrally formed with the main part 33 Y of the toner bottle, is provided in the vicinity of the position of the main part 33 Y of the toner bottle where the cap portion 34 Y is attached.
When attaching the toner bottle 32 Y to the main part of the printer 100 , the stack section 30 shown in FIG. 1 is first opened, and the bottle holder 31 is exposed. And as shown in FIG. 4 , after the toner bottle 32 Y is placed on the bottle holder 31 , the above-mentioned handle 35 Y is rotated. Then, the cap portion 34 Y which is integrally formed with the handle 35 Y is rotated, and the cap portion 34 Y and the bottle holder 31 are engaged together and fixed at the same time the shutter 36 Y (which is the cover member) is moved in the circumferential direction of the cap portion 34 Y to open the toner outlet (not shown) of the toner bottle to the outside thereof. A more detailed description of the toner bottle according to the present invention will be given later.
On the other hand, when removing the toner bottle 32 Y from the main part of the printer 100 , the handle 35 Y is rotated in the opposite direction, the engagement of the cap portion 34 Y and the bottle holder 31 is canceled, and the shutter 36 Y closes the toner outlet of the toner bottle simultaneously.
And the toner bottle 32 Y can be removed from the main part of the printer 100 with the handle 35 Y being held as it is. Thus, the toner bottle 32 Y can be attached to and detached from the top of the main part of the printer 100 , and the exchange work of the toner bottle 32 Y can be carried out easily. Moreover, the handle 35 Y is formed on the cap portion 34 Y, and the cap portion 34 Y can be easily rotated and fixed to the bottle holder 31 with the handle 35 Y.
In addition, in the state in which the toner bottle 32 Y is removed from the main part of the printer 100 , even if the handle 35 of the cap portion 34 Y is rotated, the shutter 36 Y is not moved to open the toner outlet. It is possible to prevent the shutter 36 Y from opening the toner outlet accidentally and prevent the internal toner from falling when performing the exchange work of the toner bottle 32 Y.
Next, a description will be given of the composition of the toner supply device. FIG. 5 is a perspective view of the Y, M, C and K toner supply devices in the present embodiment. There are shown the toner supply devices 40 Y, 40 M, 40 C and 40 K, and the toner bottles 32 Y, 32 M, 32 C and 32 K. FIG. 6 is a perspective view of the Y, M, C and K process cartridges and the Y, M, C and K toner supply devices in the present embodiment. The view of FIG. 5 and the view FIG. 6 are seen from different angles.
The toner supply devices 40 Y, 40 M, 40 C and 40 K are provided on the side of the middle transfer unit 15 , and are provided in the printer 100 main part. For this reason, it is not necessary to provide the toner conveyance unit in the process cartridges 6 Y, 6 M, 6 C, 6 K or the toner bottles 32 Y, 32 M, 32 C, 32 K, as in the conventional device, and the miniaturization of the process cartridges 6 Y, 6 M, 6 C, 6 K, or the toner bottles 32 Y, 32 M, 32 C, 32 K can be attained.
Moreover, in the conventional device, the process cartridge and the toner bottle are arranged in the vicinity of each other, and there is the limitation of the design. However, according to the present embodiment, the process cartridge and the toner bottle can be arranged apart from each other. Therefore, the degree of freedom of the design can improve and the miniaturization of the printer can be attained.
Moreover, according to the present embodiment, the toner outlets of the toner bottles 32 Y, 32 M, 32 C, 32 K, the toner supply devices 40 Y, 40 M, 40 C, 40 K, and the second axis side developer accommodating portions 54 Y, 54 M, 54 C, 54 K of the developing devices 5 Y, 5 M, 5 C, 5 K are arranged near the end side of the middle transfer unit 15 in the roller shaft direction. Therefore, the toner conveyance distance of the toner supply devices 40 Y, 40 M, 40 C, 40 K can be shortened, and it is effective for the miniaturization of the printer and the prevention of the toner clogging during the conveyance.
The toner supply devices 40 Y, 40 M, 40 C and 40 K have the same composition, and a description will be given of the composition of the toner supply device 40 Y for supplying the Y toner only.
As shown in FIG. 5 , the toner supply device 40 Y is mainly comprised of the drive motor 41 Y, the drive gear 42 Y, and the toner conveyance pipe 43 Y. The coil (not shown) is installed inside the toner conveyance pipe 43 Y. The drive gear 42 Y is engaged with the bottle gear 37 of the toner bottle 32 Y, and serves as the output gear which rotates the bottle main part 33 Y which is rotated integrally with the bottle gear 37 of the toner bottle 32 Y, when the drive gear 42 Y is rotated by the drive motor 41 Y.
When the concentration detection sensor (not shown) which is provided in the developing device 5 Y detects shortage of the toner concentration by the second axis side developer accommodating portion 54 Y, the drive motor 41 Y is rotates in accordance with a toner supply signal output from the control unit 57 Y.
The spiral toner guide 33 a is formed in the inner wall of main part 33 Y of the toner bottle, and the internal toner is conveyed by the rotation of the toner bottle from the rear part of the main part 33 Y to the front end where the cap portion 34 Y is provided. And the toner in the main part 33 Y of the toner bottle falls from the toner outlet (not shown) of the cap portion 34 Y to the toner receiving portion (not shown) of the toner supply device 40 Y.
The toner receiving portion is connected to the toner conveyance pipe 43 Y, and the coil (not shown) in the toner conveyance pipe 43 Y is rotated simultaneously at the same time the main part 33 Y of the toner bottle is rotated, if the drive motor 41 Y is rotated. The toner which is supplied to the toner receiving portion by the rotation of the coil is conveyed through the inside of the toner conveyance pipe 43 Y, and is supplied to the toner inlet (not shown) of the second axis side developer accommodating portion 54 Y of the developing device 5 Y. Thus, the toner concentration in the developing device 5 Y is adjusted.
In addition, the above-mentioned embodiment in which the concentration detection sensor is used may be modified so that the number of picture elements of an image formed on the photoconductor 1 Y is counted using an optical sensor, or the image concentration of a reference image formed in the photoconductor 1 Y is measured using a CCD camera. The toner supply may be performed upon the detection of shortage of the toner concentration based on the measurement results using the optical sensor or the CCD camera.
The above discussion deals with an example of the printer to which one embodiment of the present invention is applied.
As described above, even if the toner guide 33 a is provided in the inner wall of the main part 33 Y of the toner bottle, it is found out that the discharge of the toner from the toner outlet may not be performed smoothly by the rotation in the circumferential direction of the toner bottle 32 Y. The main reason for this problem is that the inner wall in the bottle is raised and the toner is not easily passed through the raised portion because the diameter of the opening of the bottle gear 37 Y provided near the outlet opening of the toner is smaller than the diameter of the inner wall of the toner bottle 32 Y.
It is desirable that the bottle gear 37 Y is formed so that the gear tooth may not be projected too much from the peripheral surface of the toner bottle 32 Y. This is also desirable for the device miniaturization. And it is desirable for stabilization of the toner supply that the bottle gear 37 is provided near the toner outlet. For this reason, even if the diameter of the opening is smaller than the inner diameter of the toner bottle 32 Y in the position of the bottle gear 37 Y, it is desirable that the toner can smoothly pass through the raised portion of the inner wall of the toner bottle.
In the following, a description will be given of the toner bottle 32 Y and the toner supply device using the toner bottle 32 Y which allows the toner to smoothly pass through the raised portion of the inner wall of the toner bottle.
FIG. 7A and FIG. 7B are perspective and front views of an embodiment of the toner bottle 32 Y in which the resin case is removed. FIG. 7A is a perspective view of the toner bottle 32 Y of the present embodiment in which the resin case is removed, and FIG. 7B is a front view of the toner bottle 32 Y of the present embodiment in which the resin case is removed.
When the resin case where the toner outlet is provided is removed from the toner bottle 32 Y, the bottle gear 37 Y will appear near the opening of the toner bottle 32 Y. This is because the bottle gear 37 Y is integrally molded with the toner bottle 32 Y.
As shown in FIG. 7B , when viewing the toner bottle 32 Y from the bottle opening side, the portion of the bottle opening which has the smallest inner diameter is the opening (called the gear opening) 37 Yi of the bottle gear 37 Y.
As indicated by the shaded lines in FIG. 7B , the toner bottle of the present embodiment is provided with the two toner guiding portions 90 Y near the gear opening 37 Yi, and each toner guiding portion 90 Y serves to move the toner inside the toner bottle beyond the raised portion to the bottle outlet when the toner bottle is rotated.
Each toner guiding portion 90 Y is a developer guiding unit which is provided in the developer container of the invention to allow the toner inside the toner bottle to be moved to the bottle outlet beyond the small-diameter portion of the bottle gear by rotation of the toner bottle.
A part of the shoulder near gear opening 37 Yi has the toner guiding portion 90 Y. When viewed through the opening, as viewed in FIG. 7B , the toner guiding portions 90 Y are at closer to a center of an axis of rotation of gear opening 37 Yi. In FIG. 8A , the exterior of the guiding portion 90 Y is shown.
FIG. 8A and FIG. 8B are side views of the toner bottle 32 Y in the present embodiment. In FIG. 8A and FIG. 8B , the side surfaces of the toner bottle when viewed in the circumferential directions which are mutually different are shown.
The toner guide 33 a for the toner delivery is formed by the double helix from the first, and the toner bottle 32 Y becomes the form which pushed out in the direction of the centerline of container rotation rather than the edge of gear opening 37 Yi in the place where the guide of two reached gear opening 37 Yi.
Namely, the toner guide 33 a is provided with the two toner guiding portions 90 Y. As shown in FIG. 7B , in the state in which the resin case is removed, the toner guiding portion 90 Y looks like the raised portion in the bottle opening when viewed from the opening front side.
Moreover, in the toner bottle 32 Y shown in FIG. 8A and FIG. 8B , at the portion adjacent to the position where the bottle gear 37 Y of the toner bottle 32 Y is provided, the shoulder unit S of the bottle is provided, and it has the two raised portions S 1 and S 2 .
The raised portions S 1 and S 2 are the toner conveyance ways by two toners guide 33 a , and when toner bottle 32 Y is seen from outside, they are such the two raised portions S 1 and S 2 . The two toner guiding portions 90 Y mentioned above are provided along with the raised portions S 1 and S 2 , respectively.
With the use of the toner guiding portion 90 Y in the toner guide 33 a , it is possible that the toner inside the toner bottle to be moved to the toner outlet beyond the small-diameter portion of the bottle gear by rotation of the toner bottle.
Even when the bottle gear 37 Y of the byway is provided from the diameter of bottle opening near the toner outlet, it enables the internal toner to transfer to the toner outlet exceeding the gear opening 37 Yi by the rotation of the bottle in the circumferential direction thereof.
FIG. 9 is a side view of a variation of the toner bottle 32 Y in the present embodiment of the invention, when viewed from the side surface of the 32 Y.
In this modification, the shoulder edge of the two raised portions S 1 and S 2 in the shoulder unit S of toner bottle 32 Y shown in FIG. 8A and FIG. 8B is beveled, and it considers as the shape of a sloping shoulder.
Except having beveled the shoulder unit S, it has the same composition as in FIG. 8A and FIG. 8B , and a description thereof will be omitted.
The toner bottle does not need to have the raised portions S 1 and S 2 like the above-mentioned embodiment, and may include sloping shoulders as shown in FIG. 9 .
In order for the toner to overcome the gear unit and to discharge it, as shown in FIG. 7B , it is like that the amount which is pushed out inside gear opening core of the toner proposal should just be as in FIG. 9 , the toner can be gradually raised from the main part side in shoulder form of FIG. 7B , and the gear unit can also be made to be overcome.
Next, a description will be given of the structure of positioning of the toner bottle 32 Y to the bottle holder 31 and the structure of opening and closing of the toner outlet.
FIG. 10A through FIG. 12 are cross-sectional views of the bottle holder 31 Y and the toner bottle 32 Y respectively.
The engagement wall 38 Y, which is a positioning unit which curves in complicated form is made to set up by the nose-of-cam side of cap portion 34 Y of toner bottle 32 Y.
The toner bottle 32 Y is the condition in which the handle 35 Y is turned to the perpendicular direction bottom, and is laid on bottle holder 31 Y ( FIG. 10 ).
This condition is also the condition in which opening of engagement wall 38 Y which curves in complicated form is turned to the perpendicular direction bottom.
The engagement board 39 Y, which is the engagement unit of the bottle holder 31 Y, advances into the loop through the opening at engagement wall 38 Y of the toner bottle 32 Y laid with this condition ( FIG. 11 ).
At this time, not the state where toner bottle 32 Y is still set normally but the toner outlet which the cap portion 34 Y does not illustrate is closed by shutter 36 Y.
The operator takes the handle 35 Y of the toner bottle 32 Y laid on bottle holder 31 Y, and rotates the handle 35 Y counterclockwise by about 45 degrees. Then, although the cap portion 34 Y rotates to the counterclockwise rotation in FIG. 12 , shutter 36 of cap portion 34 Y Y is caught in the bottom of bottle holder 31 Y. For this reason, it is possible to prevent rotation of the shutter 36 Y only ( FIG. 12 ).
And the toner outlet (not shown) which is closed by the shutter 36 Y is exposed, and it is turned to the downward perpendicular direction.
Furthermore, the engagement wall 38 Y of the cap portion 34 Y is engaged with the engagement board 39 Y of the bottle holder 31 Y, and the toner bottle 32 Y is fixed to the bottle holder 31 Y.
In FIG. 4 , when making the circumferential direction rotate toner bottle 32 Y, the friction arises between the wall in bottle holder 31 Y, and the toner bottle outer wall, and rotation may be unable to go easily smoothly.
Then, in the present embodiment, the roller 60 , which is a rotation auxiliary unit, is formed in the bottom of bottle holder 31 Y. Thereby, rotation of the toner bottle 32 Y can be made smooth.
In addition, in the present embodiment, rotation of toner bottle 32 Y is made smooth using the roller 60 . Alternatively, there is another method for making toner bottle rotation smooth. For example, it is possible to adopt the method of sticking the tape having a good sliding nature to the toner bottle. Such tape is made of a resin material containing fluorine, such as teflon (registered trademark), or containing super-macromolecule polyethylene, etc.
By the way, when making toner bottle 32 Y detach and attach from the upper part of the apparatus main part as in the above-mentioned printer, the driving force will be inputted into the input unit of the driving force provided in the toner bottle 32 Y side surface from the positions other than the upper part.
When the drive gear of the main part of the apparatus is in the unsuitable position to the input gear as the input unit at this time, rotation becomes unstable gradually with rotation of toner bottle 32 Y, and there is a possibility that toner bottle 32 Y may lose touch with the input unit.
In order to make it such fault not arise, the following creativity is put in the present embodiment.
FIG. 13 is a diagram for explaining the changes of the position of the drive gear 42 Y of FIG. 5 to the bottle gear 37 Y of the toner bottle 32 Y.
As shown in FIG. 13 , the pressure angle of the gear is made into 20 degrees. If the drive gear 42 Y (a) is placed just beside the bottle gear 37 Y so that the revolving shaft of bottle gear 37 Y and the revolving shaft of drive gear 42 Y are in the horizontal position and the counterclockwise rotation as shown in FIG. 13 is made to rotate the drive gear 42 Y, the rotating force of the drive gear 42 Y is exerted to the bottle gear 37 Y in the direction indicated by the arrow a in FIG. 13 , which direction is shifted from the downward perpendicular to the left by 20 degrees in FIG. 13 . This is because the pressure angle of the gear is 20 degrees.
Furthermore, if the drive gear 42 Y (b) is placed at the slanting position where the axis of drive gear 42 Y is located below the axis of bottle gear 37 Y, the rotating force of the drive gear 42 Y is exerted to the bottle gear 37 Y in the direction indicated by the arrow b in FIG. 13 , which direction is shifted leftward further from the direction of the arrow a.
Furthermore, if the drive gear 42 Y (c) is placed at the further slanting position, the rotating force of the drive gear 42 Y is exerted to the bottle gear 37 Y in the leftward horizontal direction indicated by the arrow c in FIG. 13 . If the drive gear 42 Y is placed further below from the position of 42 Y (c), the direction of the rotating force of the drive gear 42 Y exerted to the bottle gear 37 Y will come to be upward, and in this case, there is the possibility that the toner bottle 32 Y may come floating.
To overcome the problem, in the present embodiment, the bottle gear 37 Y and the drive gear 42 Y are positioned so that the direction of the rotating force of the drive gear 42 Y exerted to the bottle gear 37 Y always faces to the horizontal or downward direction. Specifically, the position of the drive gear 42 Y being engaged with the bottle gear 37 Y in the present embodiment falls within the range from the position of the drive gear 42 Y (a) to the position of the drive gear 42 Y (c) in FIG. 13 (or the range of 70 degrees from the horizontal position).
Then, the rotating force is applied in the direction of the respectively thick arrows a and c in each position and the force of going up at least is not applied to bottle gear 37 Y, it enables it for toner bottle 32 Y not to come floating, but to stabilize and rotate.
As mentioned above, in the present embodiment, the toner guiding portion 90 Y, which is a developer guiding unit for causing the toner to be moved to the toner outlet exceeding the gear opening 37 Yi, is provided so that the toner guiding portion 90 Y is raised from the edge of gear opening 37 Yi in the direction of the centerline of toner bottle rotation. It can raise the toner inside the bottle on the gear opening 37 Yi which projects from the inside of the toner bottle, and it is possible that the toner is moved beyond the small-diameter portion to the toner outlet.
In the present embodiment, the cap portion 34 Y is provided in which relative rotation is possible to the toner bottle 32 Y main part, and the engagement wall 38 Y as the positioning unit which engages with the engagement board 39 Y at the cap portion 34 Y is provided.
Since the positioning with the main part of the device of toner bottle 32 Y can be easily performed by laying toner bottle 32 Y in bottle holder 31 Y, and rotating cap portion 34 Y from the upper surface of the main part of the printer by this, usability is good.
Moreover, in the present embodiment, the shutter 36 Y which opens and closes the toner outlet of the cap portion 34 Y is provided, and the shutter is opened synchronizing with toner bottle 32 Y being fixed on bottle holder 31 Y, and is closed synchronizing with being removed.
The toner leakage which is not expected while special operation for opening and closing of the shutter becomes unnecessary by this and usability becomes high can also be prevented.
Moreover, the toner bottle 32 Y in the present embodiment is integrally molded with the bottle gear 37 Y. Therefore, as compared with the case where bottle gear 37 Y is used as toner bottle 32 Y and another object, part mark can be reduced and the cost cut can be aimed at.
In addition, the time and effort in the case of attaching with toner bottle 32 Y and bottle gear 37 Y can be saved, and it became unnecessary to care the attachment accuracy between toner bottle 32 Y and the gear.
Moreover, since it is not necessary to fractionate the toner bottle 32 Y and the gear, it is possible to provide good recycle characteristics. Moreover, in the present embodiment, the roller 60 is formed on the bottom of the bottle holder 31 Y. Thereby, it can be stabilized and the toner bottle 32 Y can be rotated.
In the present embodiment, the drive gear is positioned so that the pressure angle direction which is given from drive gear 42 Y to bottle gear 37 Y is turned to the horizontal direction or below. It is possible that the toner bottle 32 Y does not come floating, and it is possible to stabilize the rotation.
In addition, the same discussion is also applicable to the M, C, K toner bottles of the other toner colors in the printer, not only the Y toner bottle. They have the same composition as that of the Y toner bottle, and the same advantages can be obtained.
Next, a description will be given of the second preferred embodiment of the present invention.
In the present embodiment, the fundamental composition of the printer is essentially the same as that in the previous embodiment, and a description thereof will be omitted.
Next, a description will be given of an example of the toner supplying device of the invention.
FIG. 14 is a perspective view of an embodiment of the toner bottle 132 . Except that the colors of the toner accommodated inside differ, since it has same composition, hereinafter, the toner bottle 132 Y for Y toner is described as the example, and each toner bottles 132 Y, 132 M, 132 C, and 132 K are explained.
The toner bottle 132 Y is equipped with the bottle main part 133 Y which accommodates the developer inside and which is the long picture main part of the container.
The bottle main part 133 Y has the opening (not shown) in the direction end side of the length, and cap portion 134 Y which is the rotation unit is attached so that the opening may be covered.
The cap unit 134 Y has the toner outlet (not shown) which is the outlet which is open to the opening of the bottle main part 133 Y in the peripheral surface (hereinafter, the peripheral surface in this direction is called “peripheral surface”, and the end surface in the longitudinal direction is called “end surface”) of the toner bottle 132 Y in the direction which is perpendicular to the above-mentioned longitudinal direction.
In the state of FIG. 14 , the toner outlet is closed by the shutter 136 Y, although it is not illustrated.
The bottle main part 133 Y is a hollow cylindrical component opened by the above-mentioned opening. Embossing of the bottle main part 133 Y is carried out so that the spiral toner guide 133 a which turns the peripheral surface inside from the outside, and projects may meet the circumference side.
Moreover, the bottle gear 137 Y which is engaged with the drive gear of the toner supply device is integrally formed with the bottle main part 133 Y.
The bottle gear 137 Y has several gear teeth over the whole region of the circumference of the bottle main part 133 Y. When the rotating force of the drive gear of the toner supply device is transmitted to the bottle gear 137 Y, the bottle gear is rotated in the direction of the arrow of FIG. 14 around the central axis A extending in the longitudinal direction of the bottle main part 133 Y as the center-of-rotation axis. Thereby, the Y toner in the bottle main part 133 Y is moved to the cap portion 134 Y through the toner guide 133 a . And the toner from the inside of the bottle main part 133 Y is moved into the cap portion 134 Y through the above-mentioned opening.
FIG. 15 is a cross-sectional view of the toner bottle 132 Y in the present embodiment. In FIG. 15 , the circumference of the cap portion 134 Y of the toner bottle is shown in the cross section of the toner bottle 132 Y taken along the central axis A of the toner bottle 132 Y and passing through the toner outlet.
The engagement projection 133 b is formed in the portion of the bottle main part 133 Y which constitutes the opening C over the peripheral surface. On the other hand, the engagement projection 134 a which fits into the recess between the engagement projection 133 b and the bottle gear 137 Y is provided in the cap portion 134 Y.
And the opening C of the bottle main part 133 Y is covered by the cap portion 134 Y when the cap portion 134 Y is attached to the bottle main part 133 Y so that the engagement projection 134 a of the cap portion 134 Y may fit into the recess.
The cap portion 134 Y is a hollow cylindrical component having a diameter slightly smaller than the diameter of the bottle main part 133 Y, and the handle 135 Y which is a displacement unit is integrally formed with the peripheral surface of the cap portion 134 Y.
Moreover, the guide rail 134 b which guides the relative displacement of the shutter 136 Y to the cap portion 134 Y in the rotating direction (the forward or reverse rotation is not called for) of the bottle main part 133 Y is provided on the peripheral surface of the cap portion 134 Y.
The shutter 136 Y can be slid in the rotating direction of the bottle main part 133 Y along with the peripheral surface of the cap portion 134 Y, while it is guided by the guide rail 134 b . In the state of FIG. 15 , the shutter 136 Y is set in the closed position where the toner outlet D which is provided on the peripheral surface of the cap portion 134 Y is in the closed state.
In addition, if the shutter 136 Y is opened when the operator deals with the toner bottle 132 Y, the toner outlet D which is open to the opening C is opened and the Y toner falls.
Therefore, in the present embodiment, the shutter 136 is energized with the spring 144 , which is an energization unit shown in FIG. 14 , in the direction toward the closed position, so that the Y toner does not easily fall by the handling of the operator.
Next, a description will be given of the composition of the bottle holder of the toner supply device to which the respective toner bottles 132 Y, 132 C, 132 M, and 132 K are set.
FIG. 16 is a perspective view of the bottle holder 31 of the toner supply device in the present embodiment.
The bottle holder 31 , which is a container mounting unit, holds the four bottle holders 31 Y, 31 M, 31 C, and 31 K for attaching the four toner bottles 132 Y, 132 M, 132 C, and 132 K, respectively.
In FIG. 16 , the intermediate state of the toner bottle 132 Y being attached thereto among the four toner bottles 132 Y, 132 M, 132 C and 132 K is illustrated.
The operator puts the toner bottle 132 Y on the bottle holder 31 Y in the state where it is faced to the direction in which the handle 135 Y of the cap portion inclined to the perpendicular direction, when setting the toner bottle 132 Y to the bottle holder 31 Y.
Then, it is possible to rotate the handle 135 Y in the direction of clockwise rotation as shown, and the handle 135 Y is turned to the upward perpendicular direction similar to the other toner bottles 132 M, 132 C and 132 K as shown.
The cap unit 134 Y also rotates in one with rotation of such handle 135 Y. Although the bottle main part 133 Y will also rotate together when it attaches with cap portion 134 Y and bottle main part 133 Y and condition is strong at this time, it does not matter even if bottle main part 133 Y rotates together at this time and it does not carry out.
On the other hand, the shutter 136 Y attached to the cap portion 134 Y is stopped by the shutter stop unit (not shown) provided inside the bottle holder 31 Y, and it is not rotated by the rotation of the cap portion 134 Y.
If the operator manipulates the handle 135 Y in the present embodiment, the toner outlet D of the cap portion 134 Y is set in the opened state while it faces the inner bottom side (the downward perpendicular direction) of the bottle holder 31 Y. In addition, the toner bottles 132 M, 132 C, and 132 K of other colors are also set by the same operation on each bottle holders 31 M and 31 C and 31 K.
Next, a description will be given of the composition and operation for setting toner bottle 132 Y to bottle holder 31 Y.
FIG. 17 through FIG. 19 are cross-sectional views of the bottle holder 31 Y in the state where the front elevation when seeing toner bottle 132 Y from the cap portion 134 Y side and the wall of bottle holder 31 Y on the side of cap portion 134 Y is removed.
As shown, the engagement wall 138 Y which curves in complicated form is provided in the end surface of cap portion 134 Y. The toner bottle 132 Y is in the condition in the direction in which the handle 135 Y is inclined to the perpendicular direction, and is laid on the bottle holder 31 Y from the direction of the arrow E in FIG. 18 .
The condition is also the condition in which the break of engagement wall 138 Y which curves in complicated form is turned to the perpendicular direction bottom.
In the engagement wall 138 Y of the toner bottle 132 Y laid with this condition, the engagement board 139 Y of the bottle holder 31 Y passes along the above-mentioned break, and it advances into the space surrounded by engagement wall 138 Y ( FIG. 18 ).
At this time, the toner bottle 132 Y is still not in the normally set condition, and the toner outlet D (not shown) of the cap portion 134 Y is in the closed state by the shutter 136 Y.
In the state of FIG. 18 , the operator takes the handle 135 Y of the toner bottle 132 Y laid on the bottle holder 31 Y, and rotates it in the direction (clockwise rotation) of the arrow F in FIG. 18 so that the handle 135 Y is turned to the downward perpendicular direction.
Then, the cap portion 134 Y or the bottle main part 133 Y is rotated in the direction of the arrow F in FIG. 18 . Although the shutter 136 Y provided in the cap portion 134 Y also tends to be rotated in the direction of the arrow F in FIG. 18 with this rotation, the shutter 136 Y contacts the shutter stop unit 31 a of the bottle holder 31 Y. Thereby, the rotation of the shutter 136 Y is prevented, and the energization force of the spring 144 , and carries out relative displacement to the counterclockwise rotation in the view to cap portion 134 Y.
And the perpendicular direction bottom will be turned to and exposed by shutter 136 Y till then by the toner outlet D which suited the closed state.
Furthermore, by the rotation of the cap portion 134 Y in the direction of the arrow F as shown in FIG. 19 , the engagement wall 138 Y of the cap portion 134 Y is engaged with the engagement board 139 Y of the bottle holder 31 Y. Thereby, the setting of the toner bottle 132 Y to the bottle holder 31 Y is completed.
FIG. 20A and FIG. 20B are cross-sectional views of the toner bottle 132 Y taken in the transverse direction, which is perpendicularly to the central axis A, and passing through the toner outlet D. FIG. 20A shows the toner bottle 132 Y of the condition shown in FIG. 18 , and FIG. 20B shows the toner bottle 132 Y of the condition shown in FIG. 19 .
As shown in FIG. 20A and FIG. 20B , when the handle 135 Y is rotated in the direction of the arrow F, the toner outlet D which is in the closed state by the shutter 136 Y is opened, and it is located in the position to face in the downward perpendicular direction. Thus, under the toner outlet D facing in the downward perpendicular direction, the toner conveyance pipe (not shown) is arranged with its toner receiving opening facing in the upward perpendicular direction. Therefore, the Y toner discharged from the toner outlet D falls into the toner conveyance pipe by gravity.
Next, a description will be given of the composition and operation of the toner supply device.
FIG. 21 is a perspective view of the Y, M, C, K toner supply devices 40 Y, 40 M, 40 C, 40 K in the printer 100 .
The toner supply devices 40 Y, 40 M, 40 C, 40 K have the same composition except the colors of the toners of the there toner supply devices are different from each other. In the following, a description will be given of the Y toner supply device 40 Y as a representative example of the four toner supply devices in the printer 100 .
As shown in FIG. 21 , the toner supply device 40 Y is provided with the drive-motor 41 Y, the drive gear 42 Y, the toner conveyance pipe 43 Y, etc. as in the first preferred embodiment described previously. Moreover, although illustration is omitted, the toner supply device 40 Y is also provided with the bottle holder 31 Y described above.
When the toner bottle 132 Y is correctly set to the bottle holder 31 Y as mentioned above, the drive gear 42 Y is engaged with the bottle gear 137 Y of the bottle main part 133 Y. And when the drive gear 42 Y is rotated by the drive-motor 41 Y, the rotating force is transmitted to the bottle main part 133 Y through the bottle gear 137 Y, and the bottle main part 133 Y is rotated in the direction of the arrow G in FIG. 21 .
By the rotation, the Y toner accommodated inside the bottle main part 133 Y is transferred to the opening A (the front side of FIG. 21 ), and enters the internal space of the cap portion 134 Y. And the toner is discharged from the toner outlet D of the cap portion 134 Y, and falls into the toner conveyance pipe 43 Y.
In the toner conveyance pipe 43 Y, the coil made of a resin which is not illustrated is installed inside as in the above-mentioned first preferred embodiment, and the rotation of the toner conveyance pipe 43 Y is also carried out by the drive motor 41 Y.
The Y toner received from the toner outlet D is conveyed along the inside wall of the toner conveyance pipe 43 Y, and the coil made of the resin supplies the toner to the Y toner developing device (not shown) in the printer 100 .
In the second preferred embodiment, as shown in FIG. 15 , the cap portion 134 is attached to the bottle main part 133 by fitting the engagement projection 134 a of the cap portion 134 into the recess between the engagement projection 133 b of the bottle main part 133 and the bottle gear 137 . When the rotation driving force of the drive motor 41 Y is transmitted to the bottle main part 133 Y, the bottle main part 133 is rotated in the direction of the arrow G shown in FIG. 20B or FIG. 21 , while the frictional sliding arises between the cap portion 134 and the bottle main part 133 .
When the toner bottle 132 Y is set to the bottle holder 31 Y, the cap portion 134 Y is locked by a comparatively small force by the engagement of the engagement wall 138 Y and the engagement board 139 Y of the bottle holder 31 Y.
Moreover, in the present embodiment, when the shutter 136 Y has a relative displacement to the cap portion 134 Y in the reverse direction to the direction (the direction of the arrow G in FIG. 20B ) of the rotation of the bottle main part 133 Y as shown in FIG. 20B , the shutter 136 Y is provided so that the toner outlet D is in the closed state. Therefore, when the frictional force between the bottle main part 133 Y and the cap portion 134 Y exceeds the force to lock the cap portion 134 Y, the cap portion 134 Y is rotated with the rotation of the bottle main part 133 Y.
Consequently, the toner outlet D which is in the opened state previously is in the closed state by the shutter 136 Y. This causes the toner supply to be avoided, even when the toner supply device is driven to rotate the bottle main part 133 Y.
FIG. 22A and FIG. 22B are cross-sectional views of the bottle holder 31 Y before and after the open/close cover 50 is closed by the operator.
The stack section 50 a is constituted by the upper surface of the open/close cover 50 provided in the upper part of the printer housing 51 . The operator opens the open/close cover 50 so that the toner bottles 132 Y, 132 M, 132 C, 132 K on the bottle holder 31 are exposed, and performs the exchange work of the toner bottle.
The recess I, which accommodates the handle 135 Y of the toner bottle 132 Y inside when the open/close cover 50 is closed, is formed in the inside surface of the open/close cover 50 . In addition, although only the upper portion of the Y toner bottle 132 Y is shown in FIG. 22A and FIG. 22B , rather than the entire region of the open/close cover 50 , the recess I for each of the toner bottles 132 M, 132 C and 132 K of the other colors is formed in the inside surface of the open/close cover 50 , respectively.
When the toner bottle 132 Y is set to the bottle holder 31 Y, the open/close cover 50 is moved in the direction of the arrow H in FIG. 22A , and the attachment/detachment opening J is closed, as shown in FIG. 22B . Then the handle 135 Y enters into the recess I of the open/close cover 50 , and the handle 135 Y is fitted to the recess I.
As mentioned above, when the rotation driving force of the drive motor 41 Y is transmitted to the bottle main part 133 Y, if the force to lock the cap portion 134 Y exceeds the frictional force between the bottle main part 133 and the cap portion 134 , the cap portion 134 Y tends to rotate with the rotation of the bottle main part 133 Y.
However, the handle 135 Y which is rotated integrally with the cap portion 134 Y is regulated by the fitting of the open/close cover 50 to the recess I. That is, even if the handle 135 Y tends to be rotated counterclockwise with the rotation of the cap portion 134 Y, the handle 135 Y cannot contact the left-hand side surface of the recess I of the open/close cover 50 (which is a regulation wall), and cannot displace any more. Thereby, it is possible to prevent also the rotation of the cap portion 134 that is rotated integrally with the handle 135 Y.
Therefore, the shutter 136 Y which is positioned in the state where it is pushed against the shutter stop unit 31 a of the bottle holder 31 Y with the spring 144 is not subjected to the relative displacement to the cap portion 134 Y. Thus, the toner outlet D provided in the cap portion 134 Y will not be in the closed state.
In addition, the same discussion is applied to the toner bottles 132 M, 132 C and 132 K of the other color toners, not only the Y toner bottle 132 Y.
In the above-described embodiment, the displacement which regulates displacing so that the shutter 136 Y may carry out relative displacement to the direction which handle 135 Y which has the composition that the recess I of the handle 135 Y and the open/close cover 50 of cap portion 134 Y fits in, in the opened position corresponding to the relative position of shutter 136 Y where the toner outlet D will be in the opened state makes change the toner outlet D into the closed state—it comprises as a regulation unit.
It functions as a regulation unit to regulate carrying out relative displacement of the composition to the direction to which shutter 136 Y changes the toner outlet D into the closed state to cap portion 134 Y according to the friction with the bottle main part 133 Y.
On the other hand, even if it is going to close the open/close cover 50 as shown in the view 23 when the operator has forgotten to rotate handle 135 Y, it will be prevented that the handle 135 runs against the inside surface the open/close cover 50 , and the open/close cover 50 closes.
Therefore, the operator can notice that see the situation which cannot close the open/close cover 50 , and the set of toner bottle 132 Y is not made appropriately.
In addition, the same discussion is applied also to the toner bottles 132 M, 132 C, and 132 K of the other toner colors, not only to the Y toner bottle 132 .
Next, a description will be given another embodiment of the toner supply device of the invention.
In the present embodiment, only the composition of the inside surface of the open/close cover 50 differs from that in the previous embodiment, but the other composition of the present embodiment is essentially the same as that of the previous embodiment, and a description thereof will be omitted.
FIG. 24 is a cross-sectional view of the bottle holder 31 Y in the state where the front elevation when seeing toner bottle 132 Y from the cap portion 134 Y side and the surface of a wall of bottle holder 31 Y by the side of cap portion 134 Y are removed, and the diagram illustrating sectional drawing of the open/close cover 150 of the printer 100 .
When the open/close cover 150 is closed, the regulation wall K which is provided the inside surface the open/close cover 150 regulates that the handle 135 Y of toner bottle 132 Y rotates to the counterclockwise rotation in FIG. 24 .
If the frictional force between bottle main part 133 Y and cap portion 134 Y exceeds the force to lock the cap portion 134 Y when the bottle main part 133 Y is rotated in the direction of the arrow G in FIG. 24 as mentioned above, the cap portion 134 Y also tends to rotate in the direction of the arrow G in FIG. 24 .
However, even if the handle 135 Y which is rotated integrally with the cap portion 134 Y by the rotation tends to displace to the counterclockwise rotation in FIG. 24 , the handle 135 Y cannot contact the regulation wall K of the open/close cover 50 , and cannot be displaced any more.
Therefore, the handle 135 Y and the cap portion 134 cannot be rotated integrally. Hence, the toner outlet D provided in the cap portion 134 Y will not be in the closed state as in the above-mentioned embodiment.
In addition, the same discussion is also applicable to the other toner bottles 132 M, 132 C, 132 K of other toner colors, not only the toner bottle 132 Y.
Even if the cap portion 134 Y tends to rotate for reverse with the direction of the arrow G and handle 135 Y displaces in the present embodiment, there is no regulation wall which contacts in the displacement direction of the handle 135 Y. However, the cap portion 134 Y does not receive the torque in the direction according to the friction with rotating bottle main part 133 Y.
And since stopper 134 c is provided in guide rail 134 b which guides shutter 136 Y, shutter 136 Y does not carry out relative displacement more than stopper 134 c to cap portion 134 Y. Therefore, even if it does not regulate the displacement of the direction of the clockwise rotation of handle 135 Y, it is satisfactory in any way.
The possibility that handle 135 Y which is in the suitable opened position by having removed the portion which regulates the displacement of the direction of the clockwise rotation of handle 135 Y as in the above-mentioned embodiment may be caught in the angle of recess I will decrease.
Therefore, the handle 135 Y in the suitable opened position stops easily being able to cause trouble to opening-and-closing operation of the open/close cover 150 .
In addition, although the above explanation explained only toner bottle 132 Y for Y, the same is said of the toner bottles 132 M, 132 C, and 132 K of other colors.
Next, a description will be given of another example of the toner supplying device of the invention.
In addition, except that the form of the recess in the inside surface the open/close cover 50 differs, the present embodiment is essentially the same as the previously described embodiment, and a description about the same elements as in the previously described embodiment will be omitted.
FIG. 25 is a cross-sectional view of the bottle holder 31 Y in the state where the front elevation when seeing toner bottle 132 Y from the cap portion 134 Y side and the surface of a wall of bottle holder 31 Y by the side of cap portion 134 Y are removed, and the diagram illustrating sectional drawing of the open/close cover 250 of the printer 100 .
Although the recess I in the present embodiment is formed in the inside surface the open/close cover 250 similar to the previous embodiment, the guiding side M, which is a guiding unit, is formed in the entrance portion of the recess I.
During the operation which closes the open/close cover 250 , the guiding side M contacts the handle 135 of the toner bottle 132 Y from which toner outlet D is not in opened state completely and which is set imperfectly Y, as shown in FIG. 25A . And when closing the open/close cover 250 further, the handle 135 Y is slid along the guiding side M, and fitted into the recess I.
Thereby, the handle 135 Y comes to turn to the perpendicular direction upper part, as shown in FIG. 25B , the toner bottle 132 Y is set appropriately, and the toner outlet D will be in the opened state completely.
Thus, in the present embodiment, the toner outlet D will not be in the opened state completely, but even if the setting of toner bottle 132 Y is imperfect, operation which the open/close cover 250 closes sets appropriately so that the toner outlet D may be in the opened state completely automatically.
In addition, the same discussion is also applicable to the toner bottles 132 M, 132 C, 132 K of the other toner colors, not only the Y toner bottle 132 Y.
Next, a description will be given of another example of the toner supplying device of the invention.
FIG. 26A and FIG. 26B are cross-sectional views of the toner bottle 332 Y and the bottle holder 31 Y in the present embodiment.
In the present embodiment, the toner bottle 332 Y is in the condition in which the handle 335 Y is turned to the upward perpendicular direction, and as shown in FIG. 26A , it is laid on the bottle holder 31 Y.
And the operator takes the handle 335 Y of the toner bottle 332 Y laid on the bottle holder 31 Y, and rotates it in the direction (clockwise rotation) of the arrow F in FIG. 26A so that it faces to the direction toward which the handle 335 Y is inclined by about 45 degrees to the perpendicular direction.
Then, as in the previously described embodiment, when the cap portion 334 Y is rotated in the direction of the arrow F in the view, the shutter 336 Y is stopped by the shutter stop unit 31 a of the inside of bottle holder 31 Y.
Thereby, as shown in FIG. 26B , the toner outlet D of cap portion 334 Y will be in the opened state while facing the inner bottom side (the downward perpendicular direction) of the bottle holder 31 Y.
FIG. 27 is a cross-sectional view of the bottle holder 31 Y in the state where the front elevation when seeing toner bottle 332 Y from the cap portion 334 Y side and the surface of a wall of bottle holder 31 Y by the side of cap portion 334 Y are removed, and the diagram illustrating sectional drawing of the open/close cover 350 of the printer 100 .
The guiding projection 352 Y which projects towards the handle 335 Y of the toner bottle 332 Y is provided in the undersurface of the open/close cover 350 in the present embodiment.
Although only the upper part of the Y toner bottle 332 Y is shown among the entire region of the open/close cover 350 , the open/close cover 350 is also provided with the guiding projection corresponding to the toner bottles of the other colors, respectively.
The guiding projection 352 Y is in the form which has a cam-like roundness. In the present embodiment, if the toner bottle 332 Y is laid on the bottle holder 31 Y, the handle 335 Y of the cap portion 334 Y will be turned to the upward perpendicular direction.
If the operator does not rotate the handle 335 Y in the clockwise rotating direction as mentioned above, the open/close cover 350 has been accidentally closed although the toner outlet D is in the closed state by the shutter 336 Y.
Then, as shown in FIG. 28A , the guiding projection 352 Y of the open/close cover 350 contacts the handle 335 Y, which will turn the handle 335 Y to the perpendicular direction.
And in connection with the open/close cover 350 being closed further, the handle 335 Y will be slid along with the guiding-projection 352 Y, and will rotate about 45 degrees clockwise.
Thereby, the handle 335 Y is set in the condition that it faces to the direction in which it is inclined by about 45 degrees to the upward perpendicular direction as shown in FIG. 28B , and the toner bottle 332 Y is set appropriately and the toner outlet D will be in the opened state.
Thus, in the present embodiment, the guiding projection 352 Y functions as a guiding unit, and the toner outlet D will not be in the opened state, and even if the setting of the toner bottle is imperfect, the closing of the open/close cover 350 is set appropriately so that the toner outlet D may be in the opened state completely automatically.
Furthermore, if the open/close cover 350 is closed completely, as shown in FIG. 28B , even if the handle 335 Y tends to displace in the direction of the counterclockwise rotation in the view, since it is pushed into guiding-projection 352 Y of the open/close cover 350 , handle 335 Y cannot be displaced.
That is, even if the handle 335 Y tends to displace the toner outlet D to the direction which it is going to change into the opened state, it functions as a displacement regulation unit by which the open/close cover 350 and its guiding-projection 352 Y are regulation units, and the displacement is regulated.
Therefore, as mentioned above, even if cap portion 334 Y also tends to rotate to the direction of the arrow G in the view according to the friction with bottle main part 333 Y which rotates to the direction of the arrow G in the view, the toner outlet D will not be in the closed state.
In addition, the same discussion is also applicable to the M, C, K toner bottles of the other toner colors in the printer, not only the Y toner bottle.
Next, a description will be given of another example of the toner supplying device of the invention.
FIG. 29A is a perspective view of the toner bottle 432 Y in the present embodiment. FIG. 29B is a cross-sectional view of the circumference of the cap portion 434 Y taken along the central axis A of the toner bottle 432 Y and passing through the toner outlet D.
Although the toner bottle 432 Y in the present embodiment is essentially the same as in the previously described embodiments with respect to the composition of the bottle main part 433 Y, but the composition of the cap portion 434 Y differs.
In the present embodiment, except for the opening for discharging the Y toner from the toner outlet D, the shutter 436 Y is provided so as to cover the peripheral surface of cap portion 434 Y. And the handle 435 Y which is taken by the operator is attached to the shutter 436 Y.
Moreover, the engagement wall 438 Y, which engages with the engagement board 139 Y of the bottle holder 31 Y, is provided in the end surface of the cap portion 434 Y such that the engagement board 139 Y is surrounded by the engagement wall 438 Y.
FIG. 30A and FIG. 30B are front and cross-sectional views of the bottle holder 31 Y in the present embodiment when seeing the toner bottle 432 Y from the cap portion 434 Y side and the wall portion of the bottle holder 31 Y on the side of the cap portion 434 Y is removed.
The toner bottle 432 Y is laid on the bottle holder 31 Y in the condition in which the handle 435 Y is inclined in a suitable direction to the perpendicular direction as shown in FIG. 30A . This condition is also the condition in which the break of the engagement wall 438 Y formed integrally with the cap portion 434 Y is turned to face to the downward perpendicular direction.
At this time, the toner outlet D formed in the cap portion 434 Y is closed by the shutter 436 Y, where the outlet D faces to the downward perpendicular direction.
In the engagement wall 438 Y of the toner bottle 432 Y laid with such condition, the engagement board 139 Y of the bottle holder 31 Y passes along the above-mentioned break, and it advances in between for two engagement walls which becomes parallel mutually and counter.
The operator takes the handle 435 Y of the toner bottle 432 Y laid on bottle holder 31 Y, and rotates it in the direction (clockwise rotation) of the arrow F in FIG. 30B so that the handle 435 Y may turn to the upward perpendicular direction. Then, the shutter 436 Y also rotates to the direction of the arrow F in FIG. 30B .
Although the cap portion 434 Y also tends to rotate to the direction of the arrow F in FIG. 30B by this rotation, the rotation of the cap portion 434 Y is prevented by the engagement of the engagement wall 438 Y and the engagement board 139 Y.
Therefore, relative displacement of the shutter 436 Y is carried out to the clockwise rotation to cap portion 434 Y. And as the toner outlet D which is in the closed state is opened to the opening between the shutter 436 Y and it is shown in FIG. 30B by the shutter 436 Y till then, the toner outlet D will be exposed. Thereby, the setting of the bottle holder 31 Y of the toner bottle 432 Y is completed.
FIG. 31 is a cross-sectional view of the bottle holder 31 Y after the open/close cover 50 of the printer 100 is closed when seeing the toner bottle 432 Y from the cap portion 434 Y side and the wall portion of bottle holder 31 Y on the side of the cap portion 434 Y is removed.
In addition, the composition of the open/close cover 50 is the same as that of the previously described embodiment.
In the present embodiment, the bottle main part 433 Y will rotate, similar to the previously described embodiment, with the friction sliding with the cap portion 434 Y, if the rotation driving force from the drive motor is transmitted.
In the present embodiment, by the engagement board 139 Y being caught by the cap portion 434 Y between the engagement wall 438 Y, the rotation is impossible, and the cap portion 434 Y does not rotate according to the friction with the bottle main part 433 Y.
However, in the present embodiment, when the bottle main part 433 Y rotates, the side surface of bottle gear 437 Y and shutter 435 Y which are formed integrally with the bottle main part 433 Y will be subjected to the friction sliding.
Moreover, in the present embodiment, if the shutter 436 Y carries out relative displacement in the same direction as the direction (the direction of the arrow G in FIG. 31 ) of rotation of the bottle main part 433 Y to the cap portion 434 Y as shown in FIG. 31 , the toner outlet D will be in the closed state. Therefore, the shutter 435 Y may rotate with the rotation of the bottle main part 433 Y, and there is the possibility that the toner outlet D which is in the opened state may be closed by the shutter 436 Y.
Therefore, if the toner bottle 432 Y is set to the bottle holder 31 Y and the open/close cover 50 is closed, the handle 435 Y enters the recess I of the open/close cover 50 and it is fitted to the recess I in the present embodiment.
Hence, even if the shutter 435 Y tends to displace to the counterclockwise rotation with the rotation of the bottle main part 433 Y, the handle 435 Y integrally formed with the shutter 435 Y cannot contact the wall surface of the recess I of the open/close cover 50 (regulation wall) on the left-hand side in FIG. 31 , and cannot displace any more. Therefore, the toner outlet D of the cap portion 434 Y will not be in the closed state.
In addition, the same discussion is also applicable to the other toner bottles of the other toner colors, not only the Y toner bottle 432 Y.
As mentioned above, the printer of the present embodiment is provided with the process cartridge 6 , the exposure device 7 and the photoconductor 1 which is the image supporting medium as a visible image formation unit to form the toner image which is the visible image.
Moreover, the toner supply device 40 as a developer supplying device which has the toner bottle 132 , 332 , 432 as a developer container which equipped the printer with the main part 133 , 333 , 433 of the bottle which is the long picture main part of the container which accommodates the toner as a developer inside, and has the opening C in the direction end side of the length is formed (about the classification-by-color code, it omits also by the following explanation).
The cap portion 134 , 334 , 434 as the rotation unit which has the toner outlet D as an outlet which is open to the opening C on the side surface (peripheral surface) of the direction which is attached in the toner bottle to the main part 133 , 333 , 433 of the bottle so that the above-mentioned opening C may be covered, and intersects perpendicularly with it to the direction of the length is formed.
The toner supply device 40 is rotating the main part 133 , 333 , 433 of the bottle of the toner bottle attached to the bottle holder 31 which is the container mounting unit so that the central axis A prolonged in the direction of the length may turn into the center-of-rotation axis, it moves the toner in the main part of the bottle to the opening C, is discharged through the toner outlet D of the cap portion 134 , 334 , 434 , and supplies this to the developing device 5 which is the candidate for developer supply.
The shutter 136 , 336 , 436 which opens and closes the toner outlet D is formed in the printer by carrying out relative displacement along the rotating direction of the main part 133 , 333 , 433 of the bottle to the cap portion 134 , 334 , 434 .
Moreover, the bottle main part 133 , 333 , 433 is configured so that it is rotated while applying the frictional force to which the cap portion 134 , 334 , 434 and the shutter 136 , 336 , 436 carry out relative displacement of the toner outlet D to the direction made into the closed state to the cap portion or the shutter.
Therefore, with the rotation of the bottle main part 133 , 333 , 433 , the cap portion 134 , 334 rotates in the previously described embodiments or the shutter 436 rotates in the present embodiment, and there is the possibility that the toner outlet D which is in the opened state may be closed by the shutter 136 , 336 , 436 .
In the printer of the present embodiment, in order to discharge the toner in the main part of the bottle from the toner outlet D smoothly while rotating the main part 133 , 333 , 433 of the bottle, a regulation unit to regulate that the cap portion 134 , 334 , 434 and the shutter 136 , 336 , 436 carry out relative displacement of the toner outlet D to the direction changed into the closed state according to the friction with the main part of the bottle is provided.
Some examples of the regulation unit have been described above with the previous embodiments. It can prevent that the toner outlet D will be in the closed state with the rotation of the main part of the bottle, without changing the composition, even if it has composition rotated while it has the shutter 136 , 336 , 436 which carries out relative displacement to the cap portion 134 , 334 , 434 and the main part 133 , 333 , 433 of the bottle carries out friction sliding to the cap portion or the shutter by such composition as mentioned above.
Especially, in the previously described embodiments, when the toner bottle 132 , 332 is attached to the bottle holder 31 , the shutter stop unit 31 a , which is a rotation prevention unit to prevent the shutter 136 , 336 from rotating in the rotating direction of the main part 133 , 333 of the bottle, is provided. And it is made to carry out relative displacement of the cap portion and the shutter 136 , 336 , and opens or closes the toner outlet D by rotating the cap portion 134 , 334 in the rotating direction of the main part 133 , 333 of the bottle.
In the above-mentioned composition, when the main part 133 , 333 of the bottle rotates, the cap portion 134 , 334 also rotates with frictional force with this, and there is the possibility that the toner outlet D may be in the closed state. However, by using the regulation unit mentioned above, even if the main part 133 , 333 of the bottle rotates, the cap portion 134 , 334 does not rotate. Therefore, the toner outlet D will not be in the closed state during the toner supply.
Moreover, in the above-mentioned embodiment, when the toner bottle 432 is attached to the bottle holder 31 , engagement board 139 Y as a rotation prevention unit and engagement wall 438 Y which prevent that the cap portion 434 rotates along the rotating direction of the main part 433 of the bottle are provided.
And it has composition which is made to carry out relative displacement of the shutter and the cap portion 434 , and the toner outlet D is opened and closed by rotating the shutter 436 along the rotating direction of the main part 433 of the toner bottle.
In the above composition, when the main part 433 of the bottle rotates, the shutter 436 is also rotated with frictional force with this, and there is a possibility that the toner outlet D may be in the closed state.
However, by the regulation unit in the above-mentioned embodiment, even if the main part 433 of the bottle rotates, the shutter 436 is not rotated. Therefore, the toner outlet D will not be in the closed state during the toner supply.
Moreover, in the above-mentioned embodiments, the developer supplying device is provided to be interlocked with the displacement of the handle 135 , 335 , 435 , which is a displacement member, and the relative movement of the cap portion 134 , 334 , 434 and the shutter 136 , 336 , 436 is performed.
By providing the handle 135 , 335 , 435 , the operator can open and close the toner outlet by easy operation. And the displacement regulation unit is used, in the above-mentioned embodiments, which regulates the displacement of the handle 135 , 335 , 435 which is in the opened position corresponding to the relative position of the cap portion 134 , 334 , 434 and the shutter 136 , 336 , 436 from which the toner outlet D will be in the opened state, so that relative displacement of the cap portion and the shutter to the direction which changes the toner outlet D into the closed state is avoided by the displacement regulation unit.
In addition, in the above-mentioned embodiments, the regulation wall K, the recess I, and the guiding projection 352 are used as the displacement regulation unit respectively.
Moreover, in the above-mentioned embodiments, the visible image formation unit and the toner supply device are configured in the housing 51 . And the housing 51 has the open/close cover 50 , 150 , 250 , 350 as the cover component which opens and closes the attachment/detachment opening J which is provided for attaching the toner bottle 132 , 332 , 432 to and detaching the same from the bottle holder 31 .
And in the above-mentioned embodiments, the displacement of the knob is regulated because the handle 135 , 335 , 435 in the opened position contacts the regulation wall formed in the inside surface the open/close cover 50 , 150 , 250 , 350 in the closed state.
The regulation wall is the inner wall of the recess I, the regulation wall K, or the guiding projection 352 in the above-mentioned embodiments. According to such composition, when the toner bottle is exchanged, the operator always performs the opening operation of the open/close cover 50 , 150 , 250 , 350 , and in accordance with this operation, it is possible to prevent the toner outlet D from being in the closed state with the rotation of the main part of the bottle.
Therefore, without adding new work to the exchange work of the toner bottle, it is possible to prevent the toner outlet D from being in the closed state with the rotation of the main part of the bottle, and the work burden is not applied to the operator.
It considers as the composition positioned in the position where the handle projects toward the attachment/detachment opening J when the handle 135 is in the opened position similar to the previously described embodiment especially.
Only by adding the composition into which recess I formed in the inside surface the open/close cover by the open/close cover 50 being closed and the handle 135 in the opened position fit, then the easy composition of preparing the recess in the inside surface the open/close cover 50 . It is possible to prevent the occurrence of the toner outlet D being in the closed state by the rotation of the main part of the toner bottle.
Moreover, as in the above-mentioned embodiments, the guiding unit is provided to guide the handle to the opened position during operation which closes the open/close cover 250 , 350 to the housing 51 while the inside surface of the open/close cover contacts the handle 135 which is not in the opened position.
Even if the toner bottle 132 is not set appropriately and the toner outlet D is not in the opened state completely, the toner bottle 132 is automatically set appropriately by the closing operation of the open/close cover 50 which is usually performed by the operator.
Therefore, even if the toner bottle 132 is not set appropriately, the toner bottle 132 is appropriately set by the operator who closes the open/close cover 50 , and the operator's convenience will improve.
Moreover, the toner bottle 132 , 332 , 432 of the present embodiment has the cap portion 134 , 334 , 434 which is the rotation unit which can rotate relative to the main part of the toner bottle. The cap portion is provided with the outlet D through which the toner inside the toner bottle is discharged, and with the shutter 136 , 336 , 436 which opens or closes the outlet D by rotation of the cap portion when the toner bottle is attached to the main part of the printer.
And the handle 135 , 335 , 435 as the engagement unit which engages with the main part of the printer and prevents rotation of the cap portion is formed in the circumferential direction side section of the cap portion 134 , 334 , 434 .
Thereby, when the toner bottle 132 , 332 , 432 is set to the main part of the printer, the cap portion 134 , 334 , 434 does not rotate. Therefore, it is possible to prevent that the cap portion is rotated inappropriately in the wrong direction or the shutter 136 , 336 , 436 falls out at the time of the setting. Especially the toner bottle 132 , 332 , 432 of the present embodiment is provided so that it is detached and attached from the upper part of the main part of the printer. It is desirable that the above-mentioned handle 135 , 335 , 435 is the projection which engages with the inside of the open/close cover 50 , 150 , 250 , 350 which is the top cover of the main part of the printer.
Moreover, the toner bottle 132 , 332 , 432 of the present embodiment has the cap portion 134 , 334 , 434 as the rotation unit which can rotate relative to the main part of the container. The outlet D which discharges the developer inside the container, and the shutter 136 , 336 , 436 which open and close the outlet D.
The handle 135 , 335 , 435 as the first rotation prevention unit which prevents that the cap portion rotates in the first direction when the main part of the printer is equipped with the toner bottle, when the main part of the printer is equipped with the toner bottle and the cap portion rotates in the second direction contrary to the first direction, after opening the shutter 136 , 336 , 436 wide.
The engagement wall 138 as the second rotation prevention unit with which the cap portion prevents rotating further in the second direction is established.
While preventing the incorrect setting of the toner bottle, when the shutter is caused to open the outlet, it is possible to prevent the problem produced when the cap portion is rotated excessively.
In addition, in the above-mentioned embodiments, although, as an example of the developer container accommodating the developer, the toner bottle accommodating the toner has been described, the present invention is also applicable to other developers contained in the developer container. That is, they are the two component developer containing the toner and the magnetic carrier, the liquid-development agent containing the toner and the liquid carrier, the magnetic carrier, the liquid carrier, etc.
Moreover, in the above-mentioned embodiments, although the image forming apparatus using the electrophotographic printing method has been explained, the present invention is also applicable to another image forming apparatus which forms the image using other image forming method, such as a direct recording method.
The direct recording method is not based on the latent image support but it utilizes the discharging of the toner in the shape of a dot by the print head by which the toner adheres to the recording medium or the middle recording medium directly, and forms the image of picture elements.
Further, the present invention is not limited to the above-described embodiments, and variations and modifications may be made without departing from the scope of the present invention.
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A method of installing a toner container and a container. The container includes a body for storing toner, a handle attached to an end of the container, an opening for discharging the toner to an image forming device, and a shutter which selectively opens and closes the opening due to rotation of the handle. There is a gear which protrudes through the end of the container, and rotation of the gear causes toner in the body to be moved from the body of the container into the end of the container and subsequently out through the opening of the end of the container.
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CROSS-REFERENCE TO RELATED APPLICATION
This is a continuation-in-part of application Ser. No. 07/359,728, filed May 31, 1989, which is hereby incorporated by reference. Application Ser. No. 07/359,728 is a continuation of parent application Ser. No. 06/921,311, filed Oct. 21, 1986, now U.S. Pat. No. 4,865,706. A related application is Ser. No. 07/143,442, filed Jan. 12, 1988, which is another continuation-in-part application based on the same parent application. A second related application is Ser. No. 07/406,080, now U.S. Pat. No. 4,997,537, filed Sep. 12, 1989, which is another continuation-in-part application based on application Ser. No. 07/359,728.
FIELD OF THE INVENTION
This invention relates to electrophoresis, and more particularly, to gel-containing microcapillary colunms for high performance analytical electrophoresis.
BACKGROUND OF THE INVENTION
Electrophoresis is one of the most widely used separation techniques in the biologically-related sciences. Molecular species such as peptides, proteins, and oligonucleotides are separated by causing them to migrate in a buffer solution under the influence of an electric field. This buffer solution normally is used in conjunction with a low to moderate concentration of an appropriate gelling agent such as agarose or polyacrylamide to minimize the occurrence of convective mixing.
Two primary separating mechanisms exist, separations based on differences in the effective charge of the analytes, and separations based on molecular size The first of these mechanisms is limited to low or moderate molecular weight materials in the case of separations of oligonucleotides because in the high molecular weight range the effective charges of these materials become rather similar, making it difficult or impossible to separate them. In the case of proteins, charge and size can be used independently to achieve separations. Separations based on molecular size are generally referred to as molecular sieving and are carried out employing as the separating medium gel matrices having controlled pore sizes. In such separating systems, if the effective charges of the analytes are the same, the separation results from differences in the abilities of the different sized molecular species to penetrate through the gel matrix. Smaller molecules move relatively more quickly than larger ones through a gel of a given pore size. Oligonucleotides and medium to high molecular weight polypeptides and proteins are commonly separated by molecular sieving electrophoresis. In the case of proteinaceous materials, however, it is first generally necessary to modify the materials to be separated so that they all have the same effective charges. This is commonly done by employing an SDS-PAGE derivatization procedure, such as is discussed in "Gel Electrophoresis of Proteins," B. D. Hames and D. Rickwood, Eds., published by IRL Press, Oxford and Washington, D.C., 1981. The contents of this book are hereby incorporated herein by reference.
Sometimes it is desirable to separate proteinaceous materials under conditions which pose a minimal risk of denaturation. In such cases system additives such as urea and SDS are avoided, and the resulting separations are based on differences in both the molecular sizes and charges.
Most electrophoretic separations are today conducted in slabs or open beds. However, such separations are hard to automate or quantitate. Extremely high resolution separations of materials having different effective charges have been achieved by open tubular free-zone electrophoresis and isotachophoresis in narrow capillary tubes. In addition, bulk flow can be driven by electroosmosis to yield very sharp peaks. Such high efficiency open tubular electrophoresis has not generally been applied to the separation of medium to high molecular weight oligonucleotides, however, since these materials have very similar effective charges, as indicated above. In addition, open tubular electrophoresis does not provide size selectivity for proteinaceous materials. The questions thus arise whether electrophoresis on gel-containing microcapillaries can be employed to achieve high resolution separations of oligonucleotides, and whether the conventional procedure of SDS-PAGE can be accomplished on such microcapillaries. As demonstrated by the present disclosure, the answers to these questions are affirmative, although given its potential importance as a separating technique in the biological sciences, surprisingly little attention has been paid to microcapillary gel electrophoresis.
Hjerten has published an article in the Journal of Chromatography, 270, 1-6 (1983), entitled "High Performance Electrophoresis: The Electrophoretic Counterpart of High Performance Liquid Chromatography," in which he employs a crosslinked polyacrylamide gel in tubes having inside dimensions of 50-300 micrometers, and wall thicknesses of 100-200 micrometers. However, this work suffers from limited efficiency and relatively poor performance due in part to the use of relatively wide bore capillaries, relatively low applied fields, high electrical currents, and insufficient suppression of electroendosmosis. He has also obtained U.S. Pat. No. 3,728,145, in which he discloses a method for coating the inner wall of a large bore tube with a neutral hydrophilic substance such as methyl cellulose or polyacrylamide to reduce electroendosmosis in free-zone electrophoresis in open tubes. In a later U.S. Pat. No. 4,680,201, Hjerten discloses a method for coating the inner wall of a narrow bore capillary with a monomolecular polymeric coating of polyacrylamide bonded to the capillary wall by means of a bifunctional reagent. These capillaries are also open tubes to be used for free-zone electrophoresis.
The small amount of work in the field of gel electrophoresis in capillaries by researchers other than the present applicants has generally resulted in columns which were not highly stable and could not be subjected to sufficiently high electric fields to achieve high efficiencies and high resolution separations. Improved gel-filled capillary columns for electrophoresis which provide superior stability, efficiency, and resolution would be of great value in bioanalytical chemistry.
SUMMARY OF THE INVENTION
The above-identified need for stable and efficient gel-filled capillary electrophoresis columns is answered by the present invention, which provides an improved gel-containing microcapillary for high performance electrophoresis. It includes a microcapillary, a polymeric gel in the interior cavity of the microcapillary, and a thin layer of coating material covalently bonded to the inner surface of the microcapillary wall and preferably also bonded to the polymeric gel.
The layer of coating material between the microcapillary wall and the layer of hydrophilic polymer is generally a hydrophobic material and originates as a reagent possessing a reactive functional group capable of reacting with reactive functionalities on the interior surface of the capillary wall, silanol groups, for example. The remainder of the reagent may include a second reactive group which is capable in principle of reacting with vinyl monomers and optional crosslinking agents which when polymerized constitute the polymeric gel.
The improved gel-containing microcapillary of the invention is prepared as follows: first, the interior surface of a microcapillary is activated by contacting it with a basic material, or an acidic material, or both in sequence, then it is treated with a solution of an appropriate coating reagent capable of covalent bonding to the microcapillary wall, resulting in formation of a layer of the coating material covalently attached to the inner surface of the microcapillary wall. Following this operation, the microcapillary is filled with a solution containing at least one monomer, and optionally at least one crosslinking agent, plus at least one free radical source and an appropriate catalyst, and this mixture is allowed to polymerize in the tube, ultimately forming a polymeric matrix which fills the capillary bore. As a final step, one end of the gel-containing microcapillary is cut off cleanly and squarely.
The gel-containing microcapillaries of the invention are unusually stable and function well under applied electric fields typically of 300 volts/cm or higher, and with currents typically up to approximately 50 microamperes or above. Under these conditions, extremely high resolution separations are obtained on very small amounts of material. In addition, the microcapillaries of the invention have been demonstrated to resolve mixtures of analytes as a linear function of the logarithms of their molecular weights. Accordingly, they permit convenient and accurate molecular weight determinations on nanogram or lower amounts of unknown biopolymers.
DESCRIPTION OF THE DRAWING
The invention will be better understood from a consideration of the following detailed description taken in conjunction with the drawing in which:
FIG. 1 shows a magnified perspective view of the end of the gel-containing microcapillary of the invention;
FIG. 2 shows an electropherogram of four standard proteins, α-lactalbumin, β-lactoglobulin, trypsinogen, and pepsin on a gel-containing microcapillary column of the invention containing 10% total monomer, 3.3% crosslinker, and 0.1% SDS. The PH of the buffer was 8.6, and electrophoresis was conducted under an applied field of 400 volts/cm and a current of 24 microamperes, over a 20 centimeter migration distance;
FIG. 3 shows an electrophoretic separation of the same proteins as shown in FIG. 2, under the same electrophoretic conditions except that the column used contained 7.5% total monomers;
FIG. 4 shows an electrophoretic separation of the same proteins as shown in FIGS. 2 and 3, the electrophoretic conditions again being the same except that in this instance the column contained 5% total monomers;
FIG. 5 shows plots of the log of the molecular weight of the tested proteins versus their mobilities on three different microcapillary gel columns of the invention;
FIG. 6 shows a Ferguson plot of the data from FIGS. 2, 3, and 4;
FIG. 7 shows a graph of the Ferguson plot slopes versus molecular weights of standard proteins;
FIG. 8 shows an electropherogram of a mixture of poly(deoxyadenylic acid) oligomers, nominally of 40 to 60 bases, on a gel-containing microcapillary column of the invention containing 3% total monomer, 5% crosslinker, and no SDS. The pH of the buffer was 8.3, and electrophoresis was conducted under an applied field of 300 volts/cm and a current of 12 microamperes, over a 20 cm migration distance;
FIG. 9 shows an electropherogram of a mixture of DNA fragments of φX174RF produced by digestion with restriction enzyme Hae III. A gel-containing microcapillary column of the invention containing 6% total monomer, no crosslinker, and no SDS was used. The pH of the buffer was 8.3, and electrophoresis was conducted under an applied field of 300 volts/cm and a current of 12 microamperes, over a 20 cm migration distance;
FIG. 10 shows an electropherogram of lysozyme on a gel-containing microcapillary of the invention containing 6% total monomer, no crosslinker, and 0.1% SDS. The pH of the buffer was 7.6, and electrophoresis was conducted under an applied field of 300 volts/cm and a current of 17 microamperes, over a 20 cm migration distance.
DETAILED DESCRIPTION OF THE INVENTION
As shown in FIG. 1, the gel-containing microcapillary column of the invention includes a microcapillary 10, a layer 12 of coating material which is covalently bonded to the inner surface 14 of the microcapillary wall, and a polymeric gel material 16 within the bore of this microcapillary.
As employed herein, the term "polymeric gel" means a three-dimensional network of polymer chains held together by any of a variety of means such as covalently bonded crosslinking units, long range attractive forces, hydrogen bonds, entanglement of the molecular chains, etc., and dispersed in a liquid phase. The polymeric network provides sufficient structure for a degree of rigidity, and other components of the system occupy the spaces between the polymeric chains.
The microcapillary may be made of any of a variety of materials provided that the detection system to be employed in the electrophoresis can function adequately with the particular material employed. Suitable materials include glass, alumina, beryllia, and TEFLON. Preferably, the microcapillary is made of fused silica.
The microcapillary dimensions are important because, for a given electric field, as the internal diameter of the microcapillary is reduced, the electric current and the resultant heating produced by a particular applied electric field is reduced. Thus, for highest resolution separations it is desirable that the microcapillary have a minimum internal diameter. With the improved microcapillaries of this invention, however, this factor is somewhat less important than formerly. Accordingly, microcapillaries having internal diameters in the range between 10 and 2000 micrometers function in the invention. A preferred range of internal diameters is 10 to 200 micrometers. A polyimide coating on the outer surface of the microcapillary permits easy handling of thin-walled microcapillaries.
The polymeric gel material 16 employed can be any polymer which has a pore structure which can be varied. It may or may not be crosslinked. Preferably, the polymeric gel is a crosslinked polymer whose pore structure is varied by varying the amounts of monomer and crosslinking agent, and the reaction conditions. Examples of suitable polymeric systems are polyacrylamide, agarose, and mixtures of agarose and polyacrylamide. A preferred polymeric gel material is based on acrylamide and N,N'-methylenebisacrylamide, the N,N'-methylenebisacrylamide serving as a crosslinking agent. Other possible crosslinking agents are N,N'-(1,2-dihydroxyethylene)-bisacrylamide, N,N'-diallyltartardiamide, and N,N'-cystamine-bisacrylamide. Still other monomers and crosslinkers will suggest themselves to those skilled in the art.
The polymerization reaction is preferably initiated with ammonium persulfate or N,N,N',N'-tetramethyleneethylenediamine, though other free radical polymerization initiators may be employed, as known by those skilled in the art.
The layer 12 between the polymeric gel 16 and the inner surface 14 of the microcapillary wall is generally a hydrophobic material and is derived from a coating reagent which is capable of chemically bonding to the microcapillary wall. This reagent is generally a molecular chain having an appropriate reactive functional group at one end, though non-chain type molecules having appropriate functionalities will also serve. The end of the coating reagent which is to bond to the capillary wall carries a reactive functional group which can bond chemically to silanol groups or other reactive functionalities on the inner surface of the microcapillary. Such reactive functional groups of the reagent are typically reactive silanes such as trialkoxysilane, trichlorosilane, mono, di-, or tri-enolate silanes, and aminosilanes, where the silicon atom carries at least one group which may be readily displaced. Examples of suitable coating reagents are materials such as alkyl di- or tri- ethoxy or methoxy silanes, and alkylether di- or tri- ethoxy or methoxy silanes.
In a preferred embodiment, the coating reagent is a bifunctional material, which also contains a second functional group capable in principle of forming a covalent bond with the polymeric gel material. Such functional groups include vinyl, substituted vinyl, or any group which upon cleavage yields a free radical, but for practical purposes a vinyl group is preferred because it is then possible to form the polymeric gel in the microcapillary and chemically bond it to the microcapillary wall simultaneously. Representative bifunctional reagents are 3-Methacryloxypropyl-trimethyoxysilane, and 3-Methacryloxypropyldimethylethoxysilane, shown as a) and b) below:
a) CH 2 ═C(CH 3 )--CO 2 --(CH 2 ) 3 --Si(OCH 3 ) 3
b) CH 2 ═C(CH 3 )--CO 2 --(CH 2 ) 3 --Si(CH 3 ) 2 OC 2 H 5 .
Other possible bifunctional reagents are vinyltriacetoxysilane, vinyltri(-methoxyethoxy)silane, vinyltrichlorosilane, and methylvinyldichlorosilane, this list being intended as illustrative but not exhaustive.
In the case of capillaries to which the bifunctional reagents do not bond, e.g., TEFLON, the capillaries may be employed without a coating layer 12, or a layer of a polymer possessing the ability to adsorb to the microcapillary wall and to the polymeric gel may be employed.
For highest resolution it is necessary that at least the front end of the gel-containing microcapillary be cleanly and squarely cut perpendicular to the central axis of the microcapillary. If the surface of the polymeric gel material which is exposed at the end of the microcapillary is uneven, it is impossible to make an injection of a uniform narrow band of sample, with the result that broad peaks are obtained.
The gel-containing microcapillaries of the invention are generally prepared as follows. First, the column is activated by heating it in excess of 100° C., generally for several hours, and then bringing its interior surface into contact with an acidic material such as a dilute solution of hydrochloric or nitric acid, and/or a basic material such as ammonia gas or a solution of a base. In the heating step a temperature of 110° to 200° C. may be conveniently employed. The time of such heating can vary from a few hours to overnight or longer. In one procedure, the activating step is accomplished by flushing the microcapillary with dry ammonia gas, generally for approximately 2 hours at a temperature of approximately preferred procedure, the column may be activated by heating it as above, then filling it with a solution of a base such as an alkali metal hydroxide, e.g., an 0.1 to 1N NaOH solution, approximately 1-3 hours and conveniently overnight at a temperature typically in the range 20°-35° C., preferably at room temperature, then flushing with water.
The time and temperature employed in activating the microcapillary are selected such that they are sufficient to activate the microcapillary so that good bonding between the microcapillary and the bifunctional reagent is achieved.
The activated microcapillary is then flushed with at least 20 tubing volumes of a solution of the reagent to be employed in coating the tubing wall, and this is left to react for at least 1 hour and preferably 2 hours or longer at a temperature of 20°-35° C., preferably at room temperature, filled with this solution of coating reagent. An alternative procedure is to place the filled microcapillary column in a vacuum oven overnight at about 60° C.
The solution of coating reagent is prepared in a nonaqueous solvent such as an alcohol, an ether, a ketone, or a moderately polar halogenated solvent and typically contains between 4 and 60% coating reagent by volume. Representative solvents are methanol, dioxane, acetone, and methylene chloride. After the coating reagent has been allowed to react with the inner wall of the microcapillary, excess unreacted reagent is optionally removed by rinsing the column with a suitable solvent such as methanol, followed by a further rinsing with water. Typically at least 100 tubing volumes of solvent and water are employed.
Next, separate stock solutions of the monomers, any cross-linkers, the initiators, and free radical sources for the polymerization reaction are prepared, typically in 7 to 8 molar aqueous urea, though higher and lower concentrations of urea may be used. Gels which are intended to be non-denaturing are prepared without urea or other denaturing additives, and function well. The concentrations of these reagents are selected such that convenient aliquots of the solutions may be taken and mixed together to form a polymerization mixture having predetermined concentrations of monomer, crosslinker (if employed), and polymerization catalysts. Before mixing aliquots of these reagents together, the solutions are separately degassed for at least one hour. This degassing operation may be conducted in any of the several ways known to the art, but basically involves stirring the solutions mechanically or agitating them with ultrasound while simultaneously applying a low vacuum of approximately 20 to 30 millimeters of mercury. The preparation of these solutions is as known to the art, for example, as shown by Hames and Rickwood.
The total concentration of monomer and the concentration of crosslinking agent in these sorts of systems are generally expressed respectively as % T and % C, employing the terminology of Hjerten. In this regard, see Hjerten, Chromatographic Reviews, 9, 122-219 (1967). For the acrylamide N,N'-methylenebisacrylamide system preferably employed in this invention, the definitions of % T and % C are given below. ##EQU1## The concentrations of monomer and any crosslinking agent are predetermined according to the porosity of the polymeric matrix desired. However, the concentrations of initiator and polymerization catalyst in the reaction mixture must be determined experimentally. This is done by preparing test solutions containing the desired % T and % C, but varying the amount of initiator and polymerization catalyst employed. In the event that SDS-PAGE electrophoresis is contemplated, sodium dodecylsulfate is also included in the reaction mixture in the requisite amount, typically 0.1% (w/v). These test solutions are allowed to polymerize at or below the temperature at which the electrophoresis is to be performed and the progress of the polymerization reaction is monitored by ultraviolet spectroscopy by observing the decrease in the absorbance of the vinyl double bond. Alternatively, the microcapillary may be observed visually. Levels of initiator and polymerization catalyst are selected which cause the polymerization of the test mixture to be essentially complete in a reasonable time, such as approximately 45 to 60 minutes.
Once the correct reagent concentrations have thus been determined, a fresh mixture of the polymerization reagents is prepared and injected into the microcapillary tube, taking care not to create bubbles. A small ID TEFLON tube is used to connect the microcapillary to the syringe employed to fill the microcapillary. When the microcapillary has been filled with polymerization mixture, the syringe is removed and both ends of the microcapillary are plugged by inserting them into septa, which are maintained while the polymerization reaction occurs.
The polymerization reaction is carried out at or below the temperature which is to be employed for subsequent electrophoresis on the microcapillary column. While the polymerization reaction is occurring, the reaction may be monitored separately in an aliquot of the reaction mixture by observing the loss of absorbance due to the vinyl groups by ultraviolet spectroscopy or visually. The polymerization reaction in the column and that in the separate monitor solution are the same, although the reaction in the capillary is much faster. When the test solution indicates the polymerization reaction is essentially over, which should be at a time between 45 and 60 minutes, the reaction proceed for at least another two hours, preferably overnight, maintaining the temperature as indicated above.
An alternative and preferred polymerization procedure is to fill the microcapillary column with the solution of polymerization reagents as described above, then immediately place the column in a refrigerator at a temperature of 5°-10° C. and allow the polymerization reaction to proceed overnight.
After the polymerization reaction in the microcapillary has gone essentially to completion, the caps are removed from the microcapillary ends and at least one end of the microcapillary is cut off cleanly and squarely. One way to accomplish this is to tightly sheath an end to be cut with small diameter TEFLON tubing, then cut the TEFLON-sheathed end cleanly and squarely perpendicular to the axis of the microcapillary using a microtome, which cuts through the TEFLON sheathing, the microcapillary material, and the polymeric gel, leaving a very smooth surface of gel material exposed at the end of the microcapillary. Alternatively and preferably, the capillary may be scored carefully at a right angle to its axis be means of a sapphire cleaver, and broken cleanly by bending it. The end of the microcapillary which has been thus cut is examined under a microscope to ascertain that the cutting operation in fact produced the requisite flatness of the exposed polymeric gel. If necessary, further cuts can be made until a suitably flat end is produced. Both ends of the microcapillary are generally treated in this fashion, although it is really only necessary to have a square cut end on the front of the microcapillary.
After its preparation, the column is placed in suitable electrophoresis apparatus and a low electric field of approximately 100 to 150 volts/cm is applied for a period of about one hour. If a very noisy baseline or a zero current condition is obtained, this indicates an improperly prepared column. In this event, a new microcapillary must be prepared.
In employing the gel-containing microcapillary column of the invention in electrophoresis, apparatus and techniques which are generally known to the those skilled in the art of open tube free-zone microcapillary electrophoresis are employed. See, for example, B. L. Karger, A. S. Cohen, and A. Guttman, J. Chromatog. 492, 585 (1989); M. J. Gordon, X. Hung, S. L. Pentaney, Jr., and R. N. Zare, Science, 242, 224 (1988); and J. W. Jorgenson and K. D. Lukacs, Science, 222, 266-272 (1983). In capillary gel electrophoresis, resolution between two compounds is influenced by all the factors which affect band sharpness, including sample size, ionic materials in the samples, and the gel concentration. The latter factor is especially important, since if the gel concentration is too high the analytes are totally excluded from the column, while if it is too low little or no molecular sieving occurs. No single gel concentration is optimal for the resolution of all mixtures of proteinaceous materials or oligonucleotides. It is necessary to select appropriate gel concentrations for particular samples. Other important variables affecting electrophoresis in microcapillaries are the applied field and the electrical current employed. The sample is injected by the so-called "electrophoretic injection" technique, though other techniques known to the art, such as syringe layering injection, can serve. In the electrophoretic injection technique, the front end of the electrophoresis microcapillary is dipped into a sample solution containing an electrode of the appropriate polarity and an electric field of approximately 50 to 100 volts/cm is applied for a few seconds to cause electrophoresis of a small amount of the sample solution into the end of the microcapillary. The microcapillary is then transferred back to a solution of "running" buffer, the desired electrophoretic field is applied, and the electrophoresis is carried out in the normal way.
To aid in cooling the microcapillary, a cooling jacket or a related device is employed around the microcapillary over most of its length, excluding only the front and the rear ends of the microcapillary, which are respectively immersed in buffer solution and connected to the detector of the electrophoretic system. A cooling fluid is circulated through this jacket and maintained at whatever temperature is desired. Alternatively, an electrically controlled mechanical cooling device may be employed around the microcapillary column. Such "active" cooling is more effective in maintaining desired microcapillary temperatures than forced air or natural convection.
A method of performing high resolution molecular sieving electrophoresis for analytical purposes thus includes the steps of electrophoretically injecting an aliquot of a sample containing analytes to be separated into a gel-containing microcapillary column of the invention, applying an electric field of between 100 and 300 volts/cm or higher, allowing a current typically less than about 50 microamperes to pass through the microcapillary, and instrumentally detecting and measuring the separated analytes sequentially as they migrate past the detector.
The gel-containing microcapillaries of the invention separate analytes as a function of the logarithms of their molecular weights in a linear fashion. Accordingly, it is possible to determine molecular weights of unknown analytes by comparing their mobilities under standard electrophoretic conditions with a calibration chart plotting the log of the molecular weight of standard materials versus the mobilities of such standard materials.
A method of determining the molecular weight of an analyte therefore is to prepare a gel-containing microcapillary column according to this invention, select standard values of the electrophoretic operating parameters, the applied field being typically between 100 and 300 volts/cm or higher and the injecting onto this microcapillary column an aliquot of a standard solution containing several standard analytes of known molecular weight, applying the selected standard values of the electrophoretic operating parameters to the microcapillary column to separate the standards, measuring mobilities of the known standards under the conditions of the electrophoresis, plotting the log of the molecular weight for each of the standard materials versus its mobility under the standard operating conditions, electrophoretically analyzing an unknown solution on the same column under the same conditions, measuring the mobilities of the analytes contained therein, and finally determining the molecular weights of these analytes from a comparison with the calibration plot.
The improved microcapillary columns containing a layer of wall coating material between the polymeric gel filling and the capillary wall exhibit longer shelf lives and better stability in use than columns not containing such capillary wall coatings. Most importantly and unexpectedly, the improved microcapillary columns of the invention can be operated at high field strengths, which permit high resolution separations to be achieved in short analysis times.
The following experimental preparations are intended as exemplary only, and are not intended to limit or define the scope of the invention.
EXPERIMENTAL SECTION
Acrylamide, N,N'-methylenebisacrylamide, N,N,N',N'-tetramethyleneethylenediamine (TEMED), ammonium persulfate, sodium dodecylsulfate, TRIS buffer, and disodium hydrogen phosphate were all ultrapure or electrophoretic grade materials obtained from Swartz/Mann Biotech of Cleveland, Ohio. Somewhat less pure acrylamide from other sources could be suitably purified by recrystallizing three times and deionizing it by treatment with ion exchange resin. Urea was freshly obtained, and triply recrystallized from water/methanol. Proteins were obtained from the Sigma Chemical Company, St. Louis, Mo. and used as received. Poly(deoxyadenylic acid) and φX174RF/HaeIII DNA fragments were obtained from Pharmacia. Water was triply distilled and deionized. The fused silica microcapillary tubing preferably employed in the invention was obtained originally from Scientific Glass Engineering Inc., Austin, Tex., and for later work, from Polymicro Technologies, Inc., Phoenix, Ariz. Polymicro Technologies also supplies such tubing in various other dimensions. A sapphire cleaver useful in cutting off the ends of the microcapillaries was obtained from Ealing Electronics Corp., 22 Pleasant Street, South Natick, Mass. 01760.
Narrow bore TEFLON tubing (0.2-0.25 millimeters ID) was used for filling microcapillary tubes. All solutions were filtered through a nylon 66 or methylcellulose filter membrane having a 0.2 micrometer pore size. Analytical samples were kept frozen at -20° C. prior to use, and aliquots of these samples for experimental work were stored at 4° C. Proteins for SDS-PAGE work were prepared as known to the art.
A Soma S-3207 detector by Instrumentation for Research and Development, Inc., Kingston, Mass., was employed, and was modified for microcapillary work as described in the article by S. Terabe, et al, Anal. Chem., 56, 111-113 (1984). Data were converted to digital form using a Nelson Analytical A/D Interface model 762 SA, and stored using an IBM PC/XT computer. Other equipment known to the art will also serve.
Preparation and Testing of Gel-Containing Microcapillary Having 10% T. 3.3% C. and 0.1% SDS
Fused silica microcapillary tubing having an ID of 75 micrometers, a wall thickness of 30 micrometers, and a polyimide coating was employed. A 40 to 45 cm length of this tubing was taken for preparation of the gel-containing microcapillary. The polyimide coating was removed from a 1 cm section of one end of the tubing by burning. This end was ultimately connected to the detector of the electrophoresis apparatus.
The microcapillary tubing was heated overnight at about 120° C. in air, then flushed with dry ammonia gas at about 30° C. for approximately two hours. This and other operations reported herein as being carried out at about 30° C. were conducted at room temperature, which is generally about 3° C.± about 3° C. Next 100 μl of a 50% solution of 3-Methacryloxypropyltrimethyoxysilane in methanol were passed through the microcapillary at a temperature of about 30° C., leaving the microcapillary filled with bifunctional reagent solution, the ends of the microcapillary were connected via a short length of TEFLON tubing (also filled with bifunctional reagent solution), and the closed and reagent-filled microcapillary was left overnight at about 30° C. The TEFLON tubing was then removed from one end of the microcapillary, and the microcapillary was flushed successively with 250 μl each of methanol and water to remove unreacted bifunctional reagent. The coated microcapillary was then installed in the detector of the electrophoresis apparatus, and 15 cm sections of the treated and the untreated microcapillaries were taken for analysis. The treated microcapillary was cut to a length of somewhat greater than 20 cm, and a sheathing of TEFLON was installed on its "front" end.
Buffer solution was prepared by dissolving 1.1 g of TRIS buffer in 100 ml of 7 molar urea solution, adding 0.01 g of EDTA and 0.1 g of sodium dodecyl sulfate, and adjusting the pH to 8.6 by the addition of sodium dihydrogen phosphate.
A solution of acrylamide and N,N'-methylenebisacrylamide was prepared by combining 29 g of acrylamide and 1 g of N,N'-methylenebisacrylamide in 100 ml of buffer solution, giving a solution having a % T of 30% and a % C of 3.3%.
A solution of ammonium persulfate was prepared by dissolving 0.2 g of ammonium persulfate in 2 ml of the buffer solution.
The solutions of buffer, monomers, and ammonium persulfate were separately filtered through 0.2 micrometer filters and degassed for 2 hours by treating them with ultrasound while applying a vacuum of 20-30 mm of mercury.
Ten ml of the acrylamide-bisacrylamide solution was diluted to 30 ml with buffer solution, giving a final solution having % T 10% and % C 3.3%. One ml aliquots of this solution were experimentally treated with varying amounts of ammonium persulfate solution and TEMED, and polymerization times were monitored to determine the correct amounts of persulfate and TEMED to use. It was ascertained that addition of 2.5 μl of TEMED and 4 μl of the persulfate solution gave a polymerization time of about 45 minutes.
A 10 ml aliquot of the acrylamide-bisacrylamide solution was diluted to 30 ml with buffer solution, 2.5 μl of TEMED and 4 μl of ammonium persulfate solution were added, and in excess of 50 μl of this polymerization mixture were forced through the microcapillary until no bubbles were observed exiting the microcapillary. The injection syringe was carefully removed from the TEFLON tubing while continuing the injection, to prevent introduction of bubbles into the microcapillary. Finally, both ends of the microcapillary were immersed in "running" buffer and the polymerization was allowed to proceed at about 30° C. The polymerization of the remainder of the polymerization mixture was externally monitored. After the polymerization appeared complete, the system was left for a further two hours to ensure full polymerization, then the microcapillary front end was cut off in a microtome at a microcapillary migration distance (front end to detector) of 20 cm. The final gel-containing microcapillary was evaluated for one hour under an applied field of 100 volts/cm, and found to be satisfactory.
A mixture of four proteins, α-lactalbumin, β-lactoglobulin, trypsinogen, and pepsin, was prepared for SDS-PAGE electrophoresis in the standard manner known to the art, then a sample of this solution was electrophoretically injected onto the microcapillary column by application of an electrical field of 100 volts/cm for 15 seconds. Electrophoresis was conducted at 400 volts/cm and a current of 24 μA over the 20 cm migration distance. Results are shown in FIG. 2.
Preparation and Testing of Gel-Containing Microcapillaries Having % T=7.5 and 5%
Other microcapillary columns were prepared exactly as above, except that they possessed gels having % T=7.5% and 5%, respectively, produced by employing appropriately-diluted aliquots of the acrylamide-bisacrylamide stock solution. Mixtures of the same four proteins were separated on these microcapillary columns by electrophoresis under the same conditions as above. Results are shown in FIGS. 3 and 4 respectively.
Demonstration of Utility of the Gel-Containing Microcapillaries for Molecular Weight Determination
In FIG. 5 it is shown that the logarithms of the molecular weights of the tested proteins are a linear function of their mobilities, on each of the gels tested, showing that molecular weight determinations may be performed on the gel-containing microcapillary columns of the invention.
Demonstration of Molecular Sieving
In FIG. 6 the logs of the mobilities of the tested proteins on each of the tested microcapillary columns are plotted versus the % T, in a "Ferguson" plot. In accordance with the behavior expected for molecular sieving separations, the extrapolated mobilities at zero gel concentration of gel are essentially the same. In FIG. 7, the "Ferguson" plot slopes are shown to correlate linearly with the molecular weights of the separated materials, confirming utility of the gel-containing microcapillaries for molecular weight determinations.
Preparation and Testing of Gel-Containing Microcapillary Having 3% T, and 5% C
Fused silica microcapillary tubing having an ID of a polyimide coating was employed. A 40 to 45 cm length of this tubing was taken for preparation of the gel-containing microcapillary. The polyimide coating was removed from a 2 cm section of one end of the tubing by burning. This end was ultimately connected to the detector of the electrophoresis
The microcapillary tubing filled with 1M KOH solution and left overnight at room temperature. Next, the microcapillary was rinsed with about twenty column volumes of a 50% solution of 3-Methacryloxypropyltrimethyoxysilane in HPLC grade methanol at room temperature. The microcapillary, filled with bifunctional reagent solution, was then plugged with septa, and left overnight.
Buffer solution was prepared by dissolving 1.1 g of TRIS buffer in 100 ml of 7 molar urea solution, adding 0.01 g of EDTA, and adjusting the pH to 8.3 by the addition of boric acid.
A solution of acrylamide and N,N'-methylenebisacrylamide was prepared by combining 19 g of acrylamide and 1 g of N,N'-methylenebisacrylamide in 100 ml of buffer solution, giving a solution having a % T of 20% and a % C of 5%.
A solution of ammonium persulfate was prepared by dissolving 0.2 g of ammonium persulfate in 2 ml of the buffer solution.
The solutions of buffer, monomers, and ammonium persulfate were separately filtered through 0.2 micrometer filters and degassed for 2 hours by applying a vacuum of 20-30 mm of mercury.
1.5 ml of the acrylamide-bisacrylamide solution was diluted to 10 ml with buffer solution, giving a final solution having % T=3% and % C=5%. This solution was filtered through a 0.2 μm filter and degassed under vacuum overnight at a vacuum of about 20-22 mm of water.
To a 0.5 ml aliquot of the acrylamide-bisacrylamide solution were added 7.5 μl of a 5% v/v solution of electrophoresis grade TEMED and 7.5 μl of 5% w/v ammonium persulfate solution, and in excess of 50 μl of this polymerization mixture was forced through the microcapillary until no bubbles were observed exiting the microcapillary. The injection syringe was carefully removed from the TEFLON tubing while continuing the injection, to prevent introduction of bubbles into the microcapillary. Finally, both ends of the microcapillary were plugged with septa and the column was placed in a refrigerator and maintained between 5° and 10° C. overnight, during which time the polymerization occurred. Finally, the front end of the microcapillary was cut off at a microcapillary migration distance (front end to detector) of 20 cm. The final gel-containing microcapillary was evaluated for one hour under an applied field of 100 volts/cm, and found to be satisfactory.
A solution of a mixture of poly(deoxyadenylic acid) oligomers of nominal 40-60 bases was electrophoretically injected onto the microcapillary column by application of an electrical field of 60 volts/cm for 5 seconds. Electrophoresis 20 cm migration distance. Results are shown in FIG. 8.
Preparation and Testing of a Gel-Containing Microcapillary Having 6% T and 0% C
A third microcapillary was prepared in the same manner as the 3% T and 5% C microcapillary discussed above, except that no crosslinking agent was employed and the acrylamide stock solution was prepared by combining 30 g of acrylamide in 100 ml of buffer solution, and this was diluted five fold to yield the working acrylamide solution having 6% T. A mixture of φX174RF/Hae III DNA restriction fragments ranging from 72 to 1300 base pairs was electrophoretically injected onto the microcapillary by applying a field of 60 V/cm for 10 seconds. Electrophoresis was conducted at 300 V/cm at a current of 12 microamperes over the 20 cm migration distance. Results are shown in FIG. 9.
Preparation and Testing of a Gel-Containing Microcapillary Having 6% T, 0% C, and 0.1% SDS
A fourth microcapillary was prepared in the same manner as the 6% T and 0% C microcapillary discussed above, except that the buffer solution contained 0.1 g of sodium dodecyl sulfate per 100 ml, and the pH was adjusted to 7.6.
Although lysozyme has a pI greater than 11 and is therefore positively charged at pH=7.6 and expected to migrate to the negative electrode, the SDS-lysozyme complex is negatively charged and the complex therefore migrates toward the positive electrode. A solution of lysozyme was electrophoretically injected onto the microcapillary column by application of an electrical field of 60 V/cm for 15 seconds. Electrophoresis was conducted at 300 V/cm and a current of 17 microamperes over the 20 cm migration distance. Results are shown in FIG. 10.
Quality Control Testing of Microcapillary Columns
During their lifetimes, the gel-filled microcapillaries should be tested periodically for stability and reproducibility by measuring the electrophoretic current at various applied fields. Well-made columns in good condition exhibit a constant resistance over a range of applied fields and this is repeatable over time. In this test the applied field (V/cm) is plotted against the measured current. A straight line with a constant slope (resistance) over time indicates the column is good. Typical experimental data for an SDS-gel capillary column are presented in Table I below.
TABLE I______________________________________ E (V/cm) I (μA)______________________________________ 100 6 200 12 300 18 400 22 500 28 600 33 700 40______________________________________
These data are indicative of a well-made column, and also demonstrate the column can be operated under an applied electric field of 700 V/cm.
Other embodiments of the invention will be apparent to those skilled in the art from a consideration of this specification or practice of the invention as disclosed herein. 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.
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A microcapillary column for high performance electrophoresis. A preferred column includes a microcapillary, a thin layer of coating material covalently bonded to the inner surface of the microcapillary wall, and a gel comprising polyacrylamide polymerized in the tube, filling it. The gel-containing microcapillary is prepared by covalently bonding a layer of a suitable coating material to the inner surface of the microcapillary wall, and then causing a mixture of monomer with or without crosslinking agent, initiator, and polymerization catalyst to react in the bore of the microcapillary to form a polymeric matrix. In electrophoresis, the gel-containing microcapillary provides peak efficiencies in excess of 100,000 theoretical plates and in some instances over 1,000,000 theoretical plates within separation times of less than thirty minutes, permits trace level determinations of molecular weights, and permits electrophoretic operation at fields of 300 V/cm or higher, resulting in extremely high resolution separations.
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CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This Patent Application is a Continuation of International Patent Application No. PCT/EP2007/061264 filed on Oct. 22, 2007, entitled, “METHOD AND APPARATUS FOR CRIMPING A MULTIFILAMENT THREAD”, the contents and teachings of which are hereby incorporated by reference in their entirety.
TECHNICAL FIELD
[0002] Embodiments of the invention relate to methods for crimping a multifilament thread as well as devices for carrying out such methods.
BACKGROUND
[0003] It is generally known to initially extrude a plurality of restiform filaments from a thermoplastic melt during the production of crimped synthetic threads. The filament bundle is combined after cooling to form a smooth multifilament thread. In order to produce crimping in the individual filament strands, the multifilament thread is compressed into a thread plug. For this purpose, the filaments of the thread are preferably conveyed through a hot fluid, and deformed into loops and arcs at the surface of the thread plug. In order to fix the crimping forming in the filaments, the thread plug is thermally treated. In the case where the thread plug formation occurs by hot fluid, the thread plug heated in this manner is subsequently cooled. For this purpose the thread plug is guided at the circumference of a processing drum. The processing drum is driven in a rotating manner so that the dwell time for cooling the thread plug is determined substantially by both the circumferential speed of the processing drum, and by the degree of the wraparounds of the thread plug at the circumference of the processing drum. Since the circumferential speed of the processing drum is determined by processing speeds and can be modified only to a limited degree, the intensive cooling may be achieved only by respective wraparounds of the thread plug at the processing drum.
[0004] A method and a device are known from DE 38 00 773 C2, which discloses that the thread plug is guided in multiple wraparounds at the circumference of the processing drum. For this purpose the wraparounds of the thread plug are guided in a direct side-by-side manner at the circumference of the processing drum, such that reciprocal influences of the individual filaments of the thread plug are inevitable.
SUMMARY
[0005] A loose connection of the filaments within the thread plug can result in individual filaments getting stuck to each other in the adjacent wraparounds of the thread plug at the circumference of the processing drum, particularly in the case of thread plugs having a respectively low thread plug density. Such sticking together has an adverse effect, especially during the unraveling of the thread plug into a crimped thread, such that irregularities occur at the crimped thread, which are particularly evident in a fluctuating thread tension during the unraveling of the crimped thread. Such thread tension fluctuations have a very adverse effect, especially on the after-treatment of the thread, such as by twirling.
[0006] Embodiments of the present invention are therefore directed to further improve a method and a device for crimping a generic, multifilament thread such that it enables a safe and even unraveling of the thread plug into a crimped thread after thermal treatment of the thread plug having multiple side-by-side wraparounds at the circumference of a processing drum.
[0007] Embodiments of the invention include guiding the thread at a slant from the unraveling area of the thread such that an increasing axial space appears between the thread and the thread plug on the circumference of the processing drum during increasing wraparounds of the thread on the circumference of the processing drum.
[0008] It has been surprisingly found that the individual filament strands have no substantial differences in composition and crimping even with a non-linear transition of the thread plug into the crimped thread. However, even the filament strands that are stuck to the adjacent wraparound of the thread plug are integrated into the filament connection of the crimped thread without any irregularities during the unraveling, due to the removal of the crimped thread from the thread plug end at a slant. Due to the course of the crimped thread facing away from the wraparounds of the thread plug on the processing drum, different actions of forces are created in the unraveling area between in inner side of the thread plug, which directly faces the adjacent wraparounds of the thread plug, and an outer side of the thread plug for forming the thread. In this manner, particularly the partial areas of the filament strands placed in the inner area of the thread plug are drawn more intensely than the partial areas placed in the outer area, which substantially facilitates the unraveling of possible individual overlapping locations between the individual wraparounds of the thread plug at the circumference of the processing drum. In this regard the thread plug can be evenly transferred into the crimped thread.
[0009] In order to obtain conditions in guiding the thread and the unraveling of the thread plug that are as stable and even as possible, a further improvement of one embodiment of the invention of guiding the thread into an unraveling groove at the circumference of the processing drum after unraveling of the thread plug has proven particularly successful. In this manner reproducible and even operating conditions and straight grains can be achieved.
[0010] As a function of the thickness of the thread plug, which has a direct effect on the reciprocal influencing of the thread plug wraparounds at the circumference of the processing drum, different straight grains may be selected during the unraveling of the thread plug. However, it has been shown that the thread should be guided at the circumference of the processing drum at a gradient angle, if possible, which exceeds an angle of 10°. Depending on the looseness of the thread plug the gradient angle may be increased, where maximum gradient angles of 80° should not be exceeded.
[0011] It is of particular importance for the after-treatment of the crimped thread that a sufficient thread tension is created at the thread. For this purpose, one embodiment of the invention advantageously provides a further improvement in that the thread is guided between the unraveling area and a removal area across a wraparound area at the circumference of the processing drum, which includes a circumferential angle of at least 45°. In this manner the only minimal tensile forces required for unraveling the thread plug as opposed to the thread tensile forces required for the after-treatment can be realized. For example, no substantial tensile force acting upon the thread is desired in the unraveling area of the thread plug. The thread tensile force required for the after-treatment of the crimped thread could be, for example, 100 cN.
[0012] It has been proven particularly successful for the after-treatment, if the crimped thread is twirled into a spool before wrapping, and is twirled after removal from the processing drum by a twirling unit. In this manner the bond of the crimped filaments may be advantageously improved in the thread connection for further processing.
[0013] In order to be able to carry out the forming of the thread plug and the thermal treatment of the thread plug at a flexibility that is as high as possible, one embodiment of the method variation has proven particularly successful, in which the thread plug is conveyed by a conveyor device for the unraveling on the circumference of the processing drum, where the conveyor device and the processing drum are driven independently of one another. The thickness and the guide speed of the thread plug can be adjusted both via the conveyor device and via the processing drum.
[0014] A device is provided in order to carry out the embodiments of the method of the invention. The device according to embodiments of the invention includes a guiding apparatus for guiding the crimped thread at the circumference of the processing drum at a slant from the unraveling area of the thread plug such that an increasing axial space appears between the thread and the thread plug on the circumference of the processing drum during increasing wraparounds of the thread on the circumference of the processing drum.
[0015] Such a guiding apparatus may be formed directly at the circumference of the processing drum. However, it is also possible to embody the apparatus at a distance to the circumference of the processing drum.
[0016] It has proven particularly advantageous to form the guiding apparatus via a cast-off groove at the circumference of the processing drum. The cast-off groove is arranged at an axial offset to a guideway receiving the thread plug at the circumference of the processing drum such that a crimped thread guided from the unraveling area of the thread plug at a slant can be directly inserted into the cast-off groove. This results in very stable and reproducible operating conditions and thread guides at the circumference of the processing drum during the unraveling of the thread plug.
[0017] For the purpose of the thread guide of the crimped thread at the circumference of the processing drum one embodiment of the device according to the invention has proven particularly advantageous in which a diameter step is embodied at the circumference of the processing drum between the cast-off groove and the guideway. For this purpose the thread is guided across the diameter step at the circumference of the processing drum. In this manner, gradient angles can be realized in the straight grain, which are possible in a range of between 10° and 80°.
[0018] In order to be able to guide the crimped thread in the cast-off groove at a defined wraparound, a thread guide is preferably connected downstream of the processing drum, which tensions a guide plane with the cast-off groove. For this purpose a wraparound can be realized depending on the position of the thread guide, which preferably includes at least one circumferential angle of 45° at the circumference of the processing drum.
[0019] Since texturing apparatus having compression chambers, being vertically aligned, are usually utilized for forming thread plugs, a further improvement of the device according to one embodiment of the invention is preferably used, in which a supply unit is arranged between the texturing apparatus and the processing drum in order to obtain a transition of the thread plug from the texturing apparatus to the circumference of the processing drum that is as gentle as possible. In this manner the thread plug thicknesses preadjusted in the compression chamber may be left substantially unchanged. The transition toward the circumference of the processing drum is preferably embodied at an acute angle, or tangentially, such that the thread plug may be guided without any substantial supply.
[0020] For this purpose, the supply unit is formed by a guide mechanism and a conveyor device, which are combined into a conveyor gap such that the thread plug is conveyed along a slideway formed by the guide mechanism via the engagement of the conveyor device. For this purpose the supply and a conveying of the thread plug can be advantageously combined with little deformation. A defined and controllable discharge speed of the thread plug from the texturing apparatus is possible by the conveyor device such that a constant building up of the thread plug is ensured.
[0021] In order to realize multiple wraparounds in a substantially elongated and straight line unraveling of the thread plug at the circumference of the processing drum the embodiments of the invention preferably provide a control member that is arranged in the pivoting direction of the processing drum, at a short distance in front of the guide mechanism, such that the thread plug may be displaced by the control member after a single wraparound at the circumference of the processing drum. In this manner compact guides of the thread plug can be realized at the guideway in the processing drum.
[0022] The cooling of the thread plug at the circumference of the processing drum for the thermal treatment is preferably carried out by ambient air. For this purpose the circumference of the processing drum is embodied by a gas permeable guide casing, where low pressure acting upon the environment in the interior of the processing drum is created by a suction device. In this manner, a uniform cooling air flow can be created for flowing IS through the thread plug at the circumference of the processing drum. As an alternative, or in addition, conditioning of the air or of the thread plug may also be carried out. It is possible to utilize cold air, or to wet the thread plug using a fluid, such as water.
[0023] The device according to embodiments of the invention is preferably utilized in a spinning process, in which the crimped thread at the end of the spinning process is wound on a spool. For this purpose it is of particular advantage if an additional twirling of the crimped filaments is carried out before winding. For this purpose a twirling unit is connected downstream of the processing drum, by way of which the filaments of the multifilament crimped thread are twirled after crimping. Multifilament threads or composite threads, such as BCF threads, can be produced within the spinning process. In case of composite threads, such as the so-called tricolor thread, which is formed of three individual partial threads, the thread plug can be created by combining all three partial threads.
[0024] Regardless of the composition of the synthetic thread, a conveyor nozzles combined with a compression chamber has been proven as particularly suited as the texturing apparatus. The conveyor nozzle is connected to a compressed air source, and the compressed air is supplied to the conveyor nozzle preferably heated such that a heating of the filaments may take place simultaneously in addition to the conveying of the filaments.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] The embodiments of the invention is described in further detail below based on some example embodiments of the device according to the invention for carrying out the method according to the invention with reference to the attached figures.
[0026] They show:
[0027] FIG. 1 a schematic cross-sectional view of a first example embodiment of the device according to the invention for carrying out the method according to the invention;
[0028] FIG. 2 a schematic side view of the example embodiment of the device according to the invention in FIG. 1 ;
[0029] FIG. 3 a schematic rear view of the example embodiment of the device according to the invention in FIG. 1 ; and
[0030] FIG. 4 a schematic side view of a further example embodiment of the device according to the invention.
DETAILED DESCRIPTION
[0031] FIG. 1 , FIG. 2 , and FIG. 3 schematically show a first example embodiment of the device according to the present invention for carrying out the method of the present invention for crimping a multifilament thread in multiple views. FIG. 1 schematically shows the device in one view, and FIG. 2 in a side view. FIG. 3 shows the rear view of the example embodiment. Insofar as no reference is made to one of the figures, the following description applies to both figures.
[0032] The device, which could be integrated, for example, into a spinning process for the production of a BCF thread, has a texturing apparatus 1 in order to compress a running multifilament thread 8 into a thread plug 9 . However, depending on the percentage, the thread 8 could also be formed from one filament bundle, or from multiple filament bundles of multiple partial threads. In this example embodiment, the texturing apparatus 1 is formed by a conveyor nozzle 2 and an adjoining compression chamber 4 , as known from WO 03/004743. In this regard express reference is made to WO 03/004743 which is incorporated herein by reference, such that only a short description shall suffice at this point.
[0033] The conveyor nozzle 2 has a center thread channel 6 , into which a conveyor fluid is introduced. For this purpose the conveyor nozzle 2 is connected to a compressed air source via a fluid connection 3 . The conveyor fluid introduced into the thread channel 6 , which is preferably formed by compressed air, is heated before the introduction into the conveyor nozzle 2 . The multifilament thread 8 , which was previously formed from a plurality of extruded filaments, is suctioned into the conveyor nozzle 2 by the compressed air entering into the thread channel 6 under pressure, and conveyed along the thread channel 6 .
[0034] The compression chamber 4 has a plug channel 7 in an extension of the thread channel 6 , which is formed by a plurality of lamellae 5 that are arranged in an annular manner. The lamellae 5 are held in a housing of the compression chamber 4 , in which the conveyor fluid discharged from the plug channel 7 is discharged via a fluid outlet. Each of the synthetic filaments of the thread 8 within the plug channel 7 is deposited on the surface of the thread plug 9 into loops and arcs by means of the conveyor fluid. For this purpose the thread plug 9 continuously moves from the plug channel 7 in the direction of a plug outlet.
[0035] A supply unit 15 is provided on the outlet side of the texturing apparatus 1 for the further guiding of the thread plug. In this example embodiment the supply unit 15 is formed by a guide mechanism 11 arranged directly at the compression chamber 4 , and a conveyor device 13 , which are arranged opposite of a conveyor gap 19 . In this manner a retaining force can be created at the thread plug 9 , which counteracts the pressure of the conveyor fluid for depositing the thread 8 and for forming the thread plug 9 . In this manner a uniform thread plug formation is obtained within the compression chamber 4 and a uniform conveying of the thread plug 9 . The conveyor device 13 is embodied as a conveyor roller 14 , by which the thread plug 9 is conveyed in a single engagement into the conveyor roller 14 . For this purpose the guide mechanism 11 has a slideway 12 , on which the thread plug 9 is guided in a sliding manner. The conveyor gap 19 formed between the guide mechanism 11 and the conveyor device 13 is embodied such that the shape of the thread plug 9 is changed so that the forces required for conveying and building up a retaining force can be created at the thread plug 9 . For this purpose the guide mechanism 11 is preferably embodied as a guide rail 20 , which extends between the texturing apparatus 1 and a processing drum 26 in an L shape. The free end of the guide rail 20 forms a plug outlet 10 , which is directly associated with the circumference of the processing drum 20 . The slideway 12 in the guide rail 20 is embodied in the shape of an arc, where the conveyor gap 19 is formed in the arc-shaped section of the slideway 12 by the conveyor roller 14 positioned on the opposite side. The conveyor roller 14 is coupled to a motor 18 via a drive shaft 17 .
[0036] The deflection of the thread plug 9 from the outlet side of the texturing apparatus 1 to the plug outlet 10 is coordinated to the circumference of the processing drum 26 such that the thread plug 9 can be supplied to the processing drum 26 in a substantially tangential manner.
[0037] For the thermal treatment the thread plug 9 is deposited in a straight line at the circumference of the processing drum 26 . For this purpose the circumference of the processing drum 26 is embodied as a gas permeable guide casing 27 . The processing drum 26 is rotationally driven via a drum drive 28 . The circumferential speed of the processing drum 26 and the conveyor speed of the thread plug 9 being conveyed via the conveyor device 13 are substantially equal such that the thread plug 9 gathers at the circumference of the processing drum 26 without any change in thickness, and is further conveyed. However, it is also possible to set a circumferential speed via the drum drive 28 , which is slightly increased as opposed to the conveyor speed of the conveyor device 13 . In this manner a slight loosening of the thread plug is achieved upon gathering on the processing drum 26 . An increase of circumferential speed of the processing drum of 5% to 40% as opposed to the conveyor speed of the conveyor device has been proven to be particularly advantageous.
[0038] The processing drum 26 is closed on the front sides and is connected to a suction device 30 via a suction connection 29 . Low pressure is created in the interior of the processing drum 26 via the suction device 30 such that gaseous fluid may be suction into the interior of the processing drum 26 from the exterior via the guide casing 27 . For the treatment of the thread plug 9 the same is deposited on the guide casing 27 of the processing drum 26 and guided at the circumference of the processing drum 26 .
[0039] For this purpose the processing drum 26 has a guideway 24 on the guide casing 27 . The thread plug 9 is guided in multiple wraparounds positioned directly side-by-side. The guide mechanism 11 has a control member 23 on the end facing the processing drum 26 , which is positioned on the side of the guide rail 20 opposite of the guideway 12 . The control member 23 , which is preferably embodied as a sliding edge, has a shape that is adjusted substantially congruent to the guide casing 27 of the processing drum 26 , and is held at a short distance above the processing drum 26 . The sliding edge extends at a slant to the circumference of the processing drum 26 such that a thread plug exiting at the plug outlet 10 via the slideway 12 and deposited at the circumference of the processing drum 26 is automatically guided against the sliding edge of the sliding device 23 after a straight course on the guideway 24 of the guide casing 27 , and is displaced on the guideway 24 .
[0040] As shown in FIG. 3 the thread plug 9 is axially displaced at the circumference of the processing drum 26 by the sliding device 23 . In this manner it is possible to guide the thread plug 9 with multiple wraparounds in the guideway 24 of the guide casing 27 , wherein the wraparounds of the thread plug are directly guided side-by-side. In this regard the guide mechanism 11 may be utilized both for guiding the thread plug 9 in front of the processing drum 26 and for guiding the thread plug 9 at the processing drum 26 .
[0041] In addition to the guideway 24 , the guide casing 27 of the processing drum 26 has a cast-off groove 22 . The cast-off groove 22 and the guideway 24 are separated from each other at the circumference of the processing drum 26 by a diameter step 34 . For this purpose the groove base of the cast-off groove 22 is positioned on a diameter that is slightly smaller than the diameter of the guideway 24 . The cast-off groove 22 and the guideway 24 are embodied in a gas permeable manner at the guide casing 27 such that air flows through the guideway 24 and the cast-off groove 22 from the exterior to the interior. Depending on the thread guide a guide zone may be embodied between the cast-off groove 22 and the guideway 24 . The guide zone could also be embodied in a gas permeable or gas impermeable manner in order to guide the thread.
[0042] A thread guide 31 is connected downstream of the processing drum 26 for guiding a thread at the circumference of the cast-off groove 22 . Together with the cast-off groove 22 the thread guide 31 , which is formed in this case by a deflection roller, tensions a guide plane of the crimped thread 35 at the circumference of the processing drum 26 .
[0043] A cast-off mechanism 16 having multiple godet units 32 . 1 and 32 . 2 is connected downstream of the thread guide 31 in the guide plane. A twirling unit 33 is provided between the godet units 32 . 1 and 32 . 2 , which is connected to a compressed air source that is not illustrated. The godet units 32 . 1 and 32 . 2 are formed by a driven godet and a non-driven accompanying roller.
[0044] In the example embodiment shown in FIGS. 1 , 2 , and 3 the multifilament thread 8 , which, for example, has been removed and stretched directly from the spinning zone, is IS supplied to the texturing apparatus 1 . The thread 8 formed from a plurality of extruded filament strands is conveyed through the conveyor nozzle 6 in the thread channel 6 by way of a hot fluid and guided into the adjoining compression chamber 4 . A thread plug 9 is formed within the compression chamber in the plug channel 7 , where the filaments of the thread 8 deposit themselves in loops and arcs onto the surface of the thread plug 9 . The thread plug 9 is then guided out from the texturing apparatus 1 via the supply unit 15 at a gentle deflection toward the circumference of the processing drum 26 . For this purpose a conveyor device 13 engages into the thread plug 9 on one side and conveys the thread plug 9 continuously along the slideway 12 embodied in the guide mechanism 11 . The thread plug 9 exits continuously from the plug outlet 10 at a uniform guide speed and is taken up by the rotating processing drum 26 . The circumferential speed of the processing drum 26 and the outlet speed of the thread plug are substantially identical such that no loosening of the thread plug 9 occurs. The thread plug 9 is guided at the guideway 24 of the guide casing 27 in multiple wraparounds. For this purpose the wraparounds of the thread plug 9 are positioned side-by-side such that the individual thread plug wraparounds contact each other at the circumference of the processing drum 26 .
[0045] As shown in FIG. 2 , the thread plug 9 is held at the guideway 24 of the guide casing 27 with two wraparounds. After two wraparounds of the thread plug 9 an unraveling area 25 is formed at the circumference of the processing drum 26 , in which the thread plug 9 is unraveled into a crimped thread 35 . For unraveling the thread plug 9 into the crimped thread 35 in the unraveling area 25 the thread 35 is guided from the unraveling area of the thread plug at a slant. For this purpose a gradient angle is formed between an imagined circumferential line corresponding to the course of the last wraparound of the thread plug 9 at the circumference of the processing drum 26 , and the thread 35 , which is denoted by the Greek character a. The gradient angle a is selected such that with a progressing wrapping around of the thread 35 at the circumference of the processing 26 a continuously increasing axial distance is formed between the thread plug 9 and the crimped thread 35 . For this purpose the gradient angle a for guiding the thread 35 may be embodied within a range of 10° to 80°. The gradient angle of the thread can be selected depending on the thickness and guiding of the thread plug 9 in the guide casing 27 .
[0046] In order to be guided the thread 35 is inserted out from the guideway 24 into the cast-off groove 22 . For this purpose the diameter step 34 formed between the guideway 24 and the cast-off groove 22 represents a deflection of the thread 35 at the circumference of the processing drum 26 such that a stable thread guide is ensured out from the unraveling area at a uniform gradient angle. The thread 35 is guided within the cast-off groove 22 at a substantially straight grain in the groove base until the thread separates from the circumference of the processing drum 26 in the cast-off area 36 shown in FIG. 3 . The cast-off area 36 and the unraveling area 25 are preferably held toward each other such that a wraparound area occurs for the thread 35 at the processing drum 26 , which includes at least one circumferential angle of greater than 45°. In this manner a sufficient thread tension required for the further treatment of the crimped thread 35 can be created.
[0047] The crimped thread 35 is twirled in the twirling unit 33 by a compressed air flow for further treatment. In this manner an intensive interweavement of the crimped filaments is achieved, thus particularly improving the coherence of the thread.
[0048] FIG. 4 shows a further example embodiment of the device according to the present invention for carrying out the method according to the present embodiment of the invention in a schematic side view. The example embodiment of FIG. 4 is substantially identical to the previous example embodiment with regard to construction and function so that only the differences are explained at this point and reference is made to the previous description as to the rest.
[0049] The example embodiment of FIG. 4 has a pipe connection 37 as the supply unit 15 , which is directly associated with an end of the texturing apparatus (not illustrated). The supply unit 15 is arranged above the processing drum 26 , in which a plug outlet 10 directly ends at the circumference of the processing drum 26 .
[0050] The processing drum 26 has a guideway 24 at the guide casing 27 , which is embodied in a gas permeable manner. The guide casing 27 is rotationally driven via the drum drive 28 . The guideway 24 at the circumference of the processing drum 26 has a first area for guiding the thread plug 9 in the guide casing 27 and a second area for guiding a crimped thread 35 at an axial offset. A thread guide element 21 is associated with the circumference of the processing drum 26 in the thread guide area of the guideway 24 . The thread guide element 21 is arranged at the circumference of the processing drum 26 in the area of the second section of the guideway 24 at an axial offset to an unraveling area 25 . A cast-off mechanism (not illustrated) is connected downstream of the thread guide element 21 , which is formed in this example embodiment, for example, as an eyelet-shaped thread guide.
[0051] In the example embodiment of the device according to the invention shown in FIG. 4 the thread plug 9 is guided with two wraparounds at the circumference of the processing drum after cast off. For unraveling of the thread plug 9 the crimped thread 35 is pulled off the circumference of the processing drum 26 via the thread guide element 21 . For this purpose a helical straight grain is created on the guideway 24 , which results in an axial distance at the circumference of the processing drum 26 that is formed between the thread plug 9 and the thread 35 , which continuously grows with increasing wraparounds of the thread 35 at the guide casing 27 . In this manner a removal of the thread 35 from the unraveling area 25 is achieved at a slant. The thread 35 is guided in this helical manner at the circumference of the processing drum 26 at the gradient angle α.
[0052] For the thermal treatment a tempered gaseous fluid is suctioned in from the exterior through the gas permeable guide casing 27 , and discharged into the interior of the processing drum 26 . For this purpose the gas permeable area of the guide casing 27 extends across the entire guideway area 24 such that the thread 35 is held at the circumference of the processing drum 26 under suction.
[0053] Ambient air is preferably used for cooling an already tempered thread plug 9 guided at the circumference of the processing drum 26 in multiple wraparounds. However, it is generally also possible to suction in and discharge a fluid released in the environment of the processing drum 26 via additional fluid sources, such as for heating the thread plug. In this manner multiple treatment zones may be also advantageously embodied on the processing drum 26 such that the thread plug with a plurality of wraparounds can be treated in multiple steps.
[0054] The example embodiments illustrated in FIGS. 1 to 4 each show one processing drum, on which a thread plug having multiple wraparounds is guided. However, it is also generally possible to guide multiple thread plugs side-by-side parallel to each other on a processing drum. Advantageously, the invention also extends to such devices. In this regard it is essential that the crimped thread is guided at the circumference of the processing drum at a gradient angle, which leads to an increase of the axial distance between the thread and the thread plug.
LIST OF REFERENCE SYMBOLS
[0000]
1 texturing apparatus
2 conveyor nozzle
3 fluid connection
4 compression chamber
5 lamellae
6 thread channel
7 plug channel
8 thread
9 thread plug
10 plug outlet
11 guide mechanism
12 slideway
13 conveyor device
14 conveyor roller
15 supply unit
16 cast-off mechanism
17 drive shaft
18 motor
19 conveyor gap
20 guide rail
21 thread guide element
22 cast-off groove
23 control member
24 guideway
25 unraveling area
26 processing drum
27 guide casing
28 drum drive
29 suction connection
30 suction device
31 thread guide
32 . 1 , 32 . 2 godet device
33 twirling unit
34 diameter step
35 crimped thread
36 cast-off area
37 pipe connection
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A method and an apparatus involves crimping a multifilament thread, wherein the thread which is produced by melt spinning is compressed to a thread plug. The thread plug is cast on the circumference of rotating processing drum for thermal treatment and is wrapped around the circumference of the processing drum with many side-by-side wraparounds. Following that, the thread plug is unravelled in an unraveling area on the circumference of the processing drum into the crimped thread which is pulled of the processing drum. To obtain a continuous and regular unraveling of the thread plug with multiple wraparounds and mutual touching of the wraparounds of the thread plug, the thread is guided at a slant from the unraveling area of the thread plug such that a growing axial space appears between the thread and the thread plug, on the circumference of the processing drum, during increasing wraparounds of the thread on the circumference of the processing drum.
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CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of application Ser. No. 13/274,801, filed Oct. 7, 2011, which is a continuation of U.S. Pat. No. 8,065,169, issued Nov. 22, 2011, each having the title “Real-Time Insurance Estimate Based on Non-Personal Identifying Information.”
A portion of the disclosure of this patent document contains material which is subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by anyone of the patent document or the patent disclosure, as it appears in the Patent and Trademark Office patent file or records, but otherwise reserves all copyright rights whatsoever.
FIELD OF THE INVENTION
The invention relates generally to insurance. More specifically, the invention provides methods and systems for providing in real-time an estimated insurance premium to a user based on a minimum amount of non-personal identifying information. The invention may be used, for example, to provide estimates of premiums for auto insurance, motorcycle insurance, homeowner's insurance, condo insurance, and renter's insurance, among others. The invention is preferably accessed by a user over a computer network such as the Internet.
BACKGROUND OF THE INVENTION
Consumers often indicate that obtaining an insurance product can be a time consuming and tedious process, requiring the consumer to provide detailed information that often is not readily remembered by or available to the consumer. The consumer must research information requested by an insurance agent in order to obtain a reliable indication of how much the consumer's insurance premium might be. As a result, consumers can be hesitant to research insurance rates because of the time believed to be involved with obtaining an insurance quote.
A previous approach involved obtaining in-depth information about the consumer in order to develop a price estimate. Because insurance, e.g., auto insurance, is tailored to the individual applying for insurance and/or the property being insured, the individual would provide his or her driver's license number, home address, VIN number for the vehicle(s) and other specific personal information. Based on this specific personal information, the agent or insurance company would use sophisticated quoting tools and charts to develop a quote. The extent of this personal information creates a barrier to marketing and lead generation because it is time-consuming for the customer to provide. Additionally, as consumers' sensitivity to providing personal information has increased, consumers increasingly do not want to provide such extensive information in order to shop for insurance.
As an alternative to providing detailed information to obtain a quote, consumers often request a less precise estimate of what his or her insurance premium might be. However, given the large number of factors that must be taken into account in determining an insurance quote, providing even an estimate can be a difficult task. The basic tension in providing a meaningful estimated insurance quote to a member of the public, who is not an existing customer of an insurance company, is accuracy versus speed. Both elements of this equation are largely dependent upon the amount of information provided—the information which forms the basis for an estimated quote. If the person submits a great deal of information to the process then the estimate will likely be much more accurate, but the process will also be very time consuming and cumbersome to the person. At the other end of the spectrum, if the person submits very little information to the quoting process then the process is much more “user friendly” and quicker; however, the estimate may not be very accurate.
Inaccurate estimates result in lower chances of closing on a new policy with the consumer as well as decreased customer satisfaction. When the consumer subsequently provides more detailed information and the policy for that individual is developed, the price might not meet the expectations of the consumer because his or her expectations were premised on the estimate that turned out to be inaccurate.
BRIEF SUMMARY OF THE INVENTION
The following presents a simplified summary of the invention in order to provide a basic understanding of some aspects of the invention. This summary is not an extensive overview of the invention. It is not intended to identify key or critical elements of the invention or to delineate the scope of the invention. The following summary merely presents some concepts of the invention in a simplified form as a prelude to the more detailed description provided below.
To overcome limitations in the prior art described above, and to overcome other limitations that will be apparent upon reading and understanding the present specification, aspects of the present invention are directed to methods and systems that quickly develop an insurance estimate based on a minimum of readily known information obtained from an individual consumer. The individual consumer can self-declare and input the information according to predetermined value filters. Through a range of choices provided to the individual consumer, the consumer can select from a number of coverage options that most accurately reflect his or her needs. According to an aspect of the invention, the individual consumer does not need to identify herself or provide information which could be used to identify her, thereby avoiding privacy concerns on the part of the consumer. That is, only readily known information is requested so the user does not have to track down or research the information, and only non-personal identifying information is requested, thereby alleviating privacy concerns while still providing an estimate to the user quickly, e.g., under 30 seconds.
A first aspect of the invention describes a method for providing an insurance estimate by analyzing a rate model to determine, for each of a plurality of rate factors, an insurance risk associated with multiple different values of the rate factor. The method determines one or more assumptions based on historical rate plan data, where each assumption is true for at least a predetermined percentage of historical insured individuals in the historical rate plan data, and selects a subset of the plurality of rate factors that, combined with the one or more assumptions, yields a substantially accurate insurance estimate when a value input filter corresponding to the rate factor is applied to the historical rate plan data and is re-input into the rate model. Upon receiving user input for each of the subset of the plurality of rate factors using each corresponding value input filter, the method determines an estimated insurance premium using the rate model based on the received user input.
According to other aspects of the invention, the method may determine one of the value rate filters by grouping values of the corresponding rate factor that yield minimal risk differentiation. Each rate factor in the subset of the plurality of rate factors preferably corresponds to non-personal identifying data.
According to an aspect of the invention, an automobile insurance estimate is provided and the subset of the plurality of rate factors consists of: zip code, gender, marital status, driving history, vehicle year, vehicle make, vehicle model, ownership status of real estate, credit worthiness, and length of time with current automobile insurer.
These and other aspects of the invention are described in more detail below to provide methods and systems for providing estimated insurance quotes and/or premiums.
BRIEF DESCRIPTION OF THE DRAWINGS
A more complete understanding of the present invention and the advantages thereof may be acquired by referring to the following description in consideration of the accompanying drawings, in which like reference numbers indicate like features, and wherein:
FIG. 1 illustrates a system and network architecture that may be used according to one or more illustrative aspects of the invention.
FIG. 2 illustrates a method of providing an insurance estimate according to an illustrative aspect of the invention.
FIG. 3 illustrates a screen shot of a user interface according to an illustrative aspect of the invention.
FIG. 4 illustrates a screen shot of a user interface according to an illustrative aspect of the invention.
FIG. 5 illustrates a screen shot of a user interface according to an illustrative aspect of the invention.
FIG. 6 illustrates a screen shot of a user interface according to an illustrative aspect of the invention.
FIG. 7 illustrates a screen shot of a user interface according to an illustrative aspect of the invention.
FIG. 8 illustrates a screen shot of a user interface according to an illustrative aspect of the invention.
FIG. 9 illustrates a screen shot of a user interface according to an illustrative aspect of the invention.
FIG. 10 illustrates a screen shot of a user interface according to an illustrative aspect of the invention.
FIG. 11 illustrates a screen shot of a user interface according to an illustrative aspect of the invention.
FIG. 12 illustrates a screen shot of a user interface according to an illustrative aspect of the invention.
FIG. 13 illustrates a screen shot of a user interface according to an illustrative aspect of the invention.
FIG. 14 illustrates a screen shot of a user interface according to an illustrative aspect of the invention.
FIG. 15 illustrates a screen shot of a user interface according to an illustrative aspect of the invention.
FIG. 16 illustrates a screen shot of a user interface according to an illustrative aspect of the invention.
FIG. 17 illustrates a screen shot of a user interface according to an illustrative aspect of the invention.
FIG. 18 illustrates a method of providing an insurance estimate according to an illustrative aspect of the invention.
DETAILED DESCRIPTION OF THE INVENTION
In the following description of the various embodiments, reference is made to the accompanying drawings, which form a part hereof, and in which is shown by way of illustration various embodiments in which the invention may be practiced. It is to be understood that other embodiments may be utilized and structural and functional modifications may be made without departing from the scope of the present invention.
Aspects of the invention provide an insurance estimating tool that calculates an estimated insurance quote for a consumer without requiring the consumer to disclose personally identifying information. The consumer does not have to disclose name, social security number (SSN), address, vehicle VIN number, or other information unique to that person or specific property being insured. Instead the consumer is allowed to self-declare general characteristics about him or herself or the property. The specifically requested characteristics are preferably highly-predictive of the consumer's potential insurance quote and allow for the development of a range of estimates from which the consumer can select one that best applies to him or her.
FIG. 1 illustrates one example of a network architecture and data processing device that may be used to implement one or more illustrative aspects of the invention. Various components 103 , 105 , 107 , and 109 may be interconnected via a network 101 , such as the Internet. Other networks may also or alternatively be used, including private intranets, local LANs, wireless WANs, personal PANs, and the like. The components may include an insurance rate server 103 , web server 105 , and client computers 107 , 109 . Rate server 103 provides overall control and administration of providing insurance quotes and estimates to users according to aspects described herein. Rate server 103 may be connected to web server 105 through which users interact with and obtain insurance rates. Alternatively, rate server 103 may act as a web server itself and be directly connected to the Internet. Rate server 103 may be connected to web server 105 through the network 101 (e.g., the Internet), or via some other network (not shown). Users may interact with the rate server 103 using remote computers 107 , 109 , e.g., using a web browser to connect to the rate server 103 via one or more externally exposed web sites hosted by web server 105 . Servers and applications may be combined on the same physical machines, and retain separate virtual or logical addresses, or may reside on separate physical machines. FIG. 1 illustrates but one example of a network architecture that may be used, and those of skill in the art will appreciate that the specific network architecture and date processing device used may vary, and are secondary to the functionality that they provide, as further described below.
Each component 103 , 105 , 107 , 109 may be any type of known computer, server, or data processing device. Rate server 103 , e.g., may include a processor 111 controlling overall operation of the rate server 103 . Rate server 103 may further include RAM 113 , ROM 115 , network interface 117 , input/output interfaces 119 (e.g., keyboard, mouse, display, printer, etc.), and memory 121 . Memory 121 may further store operating system software 123 for controlling overall operation of the data processing device 103 , control logic 125 for instructing rate server 103 to perform aspects of the invention as described herein, and other application software 127 providing secondary support or other functionality which may or may not be used in conjunction with aspects of the present invention. The control logic may be referred to herein as the rate server software 125 . Functionality of the rate server software may refer to operations or decisions made automatically based on rules coded into the control logic, or made manually by a user providing input into the system
Memory 121 may also store data used in performance of one or more aspects of the invention, including a rate model database 129 and a historical database 131 . Rate model database 129 may define rules, restrictions, qualifications, and conditions which, when met, result in providing a customer an insurance product at a given rate, i.e., when the customer pays an insurance premium as determined by a rate model or rate models encoded within the rate model database 129 . For example, one rule might indicate that a married male driver has reduced insurance as compared to a single male driver, or that a driver under the age of 25 must pay a higher rate than a driver who is 25 years old or older. Historical database 131 stores information about what actual customers have paid for insurance in the past, as well as the information on which those insurance prices were based, e.g., age, insured products, types of insurance, length of term with insurance company, etc. In some embodiments, the rate model database may include the historical database. That is, the information can be stored in a single database, or separated into different logical, virtual, or physical databases, depending on system design.
Those of skill in the art will appreciate that the functionality of data processing device 103 as described herein may be spread across multiple data processing devices, for example, to distribute processing load across multiple computers, to segregate transactions based on geographic location, insurer, insured, type of insurance, etc. In addition, one or more aspects of the invention may be embodied in computer-usable data and computer-executable instructions, such as in one or more program modules, executed by one or more computers or other devices. Generally, program modules include routines, programs, objects, components, data structures, etc. that perform particular tasks or implement particular abstract data types when executed by a processor in a computer or other device. The computer executable instructions may be stored on a computer readable medium such as a hard disk, optical disk, removable storage media, solid state memory, RAM, etc. As will be appreciated by one of skill in the art, the functionality of the program modules may be combined or distributed as desired in various embodiments. In addition, the functionality may be embodied in whole or in part in firmware or hardware equivalents such as integrated circuits, field programmable gate arrays (FPGA), and the like. Particular data structures may be used to more effectively implement one or more aspects of the invention, and such data structures are contemplated within the scope of computer executable instructions and computer-usable data described herein.
As previously discussed, aspects of the invention provide a tool that calculates, determines, or develops an insurance estimate for a consumer without requiring the consumer to disclose personally identifying information. Unlike previous approaches used to estimate insurance premium, aspects of the present invention provide an insurance estimate based on a few pieces of information readily available to the consumer without requiring the consumer to perform exhaustive research to obtain the requested information. The user can preferably enter the information through an intuitive and user-friendly web-based application.
FIG. 2 illustrates a method for providing an insurance estimate according to one or more aspects of the invention. Initially, in step 201 , an insurance provider analyzes the rate model in conjunction with the historical rate data to determine, for each of a plurality of rate factors, an insurance risk associated with multiple different values of the rate factor. A rate factor, as used herein, refers to any variable or information associated with a consumer that can affect the price the consumer might pay for an insurance product. Rate factors may include, e.g., age, gender, geographic location, marital status, car make, car model, car year, VIN number, accident history, credit history and/or rating, occupation, educational history, educational performance, and criminal record, among other things. This is not an exhaustive list of rate factors, but rather is illustrative of the type of information that an insurance company might request prior to providing an insurance contract to a customer. During step 201 , each possible rate factor is analyzed to determine whether it provides meaningful risk differentiation based on various input values and, if so, it is determined what input values should be grouped together to simplify the input process while providing meaningful information from which an insurance estimate could be based.
As an example, a consumer's age may provide a good indication of the risk associated with that consumer. I.e., an 18 year old driver typically has a much higher risk of getting into an automobile accident than a 40 year old driver. However, an 18 year old driver might have a risk very similar to that of a 19 year old driver (all other things being equal), and thus the system might not care whether a consumer is 18 or 19 years old for purposes of providing an estimate. As a result, those performing the analysis may determine that a consumer's age should be included in the estimation process, but that a specific age is not required. Instead, the user might only be required to indicate an age range he or she is in. Alternatively, a user may be required to indicate an exact age.
As another example, a consumer's driving history may be relevant, but there might be little differentiation in risk among all users who have had 2 or more accidents or moving violations in the past five (or some other number) of years. Thus, while driving history may also be required, the consumer might only be required to provide an indication of whether the consumer has had 0, 1, or greater than 1 accidents or moving violations in the past five years. For example, two or more accidents and violations within the last five years for a single driver all get approximately the same rate, because having 3 or 4 accidents does not have a significant impact on the quote as compared to 2 accidents because few drivers have more than 2 incidents. The three possible values of 0, 1, and 2+ are defined by and referred to as a value input filter corresponding to the driving history rate factor. Value input filters also act to ensure that valid and/or understandable input is received from a user (e.g., the response “I don't recall any” would not be particularly helpful to an automated insurance estimation tool).
In step 203 , it is determined which rate factors provide the best indication of resulting insurance rates, as well as levels of those rate factors that provide meaningful variations in risk. That is, the analysis in step 203 may include a two-part process: first, determine which rate factors act as the best indicators of risk, and second, determine cutoff values or ranges within that rate factor that provide more meaningful differentiation between levels of risk. There are different combinations of rate factors that might result in fairly accurate insurance estimates. However, in order to encourage users to complete the insurance estimation process, the insurer preferably selects only rate factors that do not yield personal identifying information, e.g., name, street address, telephone number, driver's license number and/or social security number are not used. The possible rate factors may be ranked and selected so that a minimum number of rate factors may be used to provide the best indication of potential risk regarding a consumer. Factors may also be selected on the basis of whether the consumer is likely to object to providing the information in an informal estimation process, and also based on whether the consumer is likely to have the information readily available (as opposed to requiring further or subsequent research of information not immediately available to the consumer). Other bases may also be used to select rate factors for use in the estimation process.
According to an illustrative embodiment of the invention, the following rate factors and value input filters, based on information obtained from prospective driver(s), may be used in determining an automobile insurance estimate:
TABLE 1
Auto Insurance Rate Factors and Value Input Filters
Rate Factor
Value Input Filter
Zip Code
Compare against known list of valid
zip codes
Gender
Male, Female
Marital Status
Single, Married
Age
Yearly increments from 16-55, or
55+
Accidents/Violations in
0, 1, 2+
past 5 years
Car Year
Valid Year, e.g., 1970-Present year
Car Make
Manufacturer known to have made
at least 1 car during selected Car
Year
Car Model
Model of car known to have been
made by manufacturer selected as
Car Make
Residence
Own, Rent, Neither
General Bill Payment History
Excellent, Very Good, Good, Fair,
Poor
Length of continuous
0, 0.5, 1, 2, 3+, 5+, 10+ years
auto insurance
Next, in step 205 , based on the selected rate factors and value input filters, assumptions are determined that are likely to yield realistic estimates based on the value input filters for the selected rate factors. By using key assumptions derived from the analyzed historical data, the quoting process is quicker and more efficient than previous solutions. The historical data is analyzed to determine the information corresponding to the previous consumers that yields accurate results when the previous consumers' information is used as input back into the estimation process. That is, the historical data is analyzed to determine what assumptions need to be made, after using the historical data as input into the estimation process, to yield realistic estimates when the historical data is plugged back into the rate model 129 . Assumptions can include selections made by a majority of previous consumers regarding insurance options, or may include information known or associated with a majority of previous insurance purchasers. For example, the historical data may be analyzed to determine what level of insurance previous consumers selected, e.g., $100K per person/$300K per accident, $500 deductible, medical payment options, etc. The historical data may also be analyzed to determine what information is common to most consumers seeking automobile insurance, e.g., that all drivers were licensed at age 16 and have verifiable driving records, and/or that no driver in the household has had their license suspended or revoked in the past 5 years.
As an example, the historical data may include actual rates paid by previous consumers, as well as those consumers' ages, driving histories, car information, etc. Information for one or more of the previous consumers is used as input into the estimation model, e.g., the rate model 129 . The results are compared with the actual rates the consumer paid, which can then be used to determine which assumptions need to be made so that the actual rate and the estimated rate are within a predetermined amount of each other. The predetermined amount can be any percentage or dollar amount based on the desired accuracy of the system.
As another example, assumptions may be generated from information corresponding to the previous consumers not related to the selected rate factors, e.g., selected insurance levels, miles driven to work, etc. In such an embodiment, the previous consumers need not necessarily be used as input back into the rate model to determine assumptions, but rather the assumptions may be generated based on information common to many previous customers. That is, historical data trends may be used to generate assumptions for future estimates.
According to an illustrative embodiment, the following assumptions may be used during the estimation process:
Driver Assumptions: 1. All drivers were licensed at age 16 and have verifiable driving records. 2. No driver in the household has had their license suspended or revoked in the past 5 years (MD and WA: past 3 years). 3. All drivers reside at the primary residence and all vehicles are garaged and/or parked at that residence. The primary residence is assumed to be within the ZIP code entered. 4. For accidents and violations entered by the consumer, the insurer has assumed that all accidents are “at-fault” accidents, and that all violations are minor. The insurer may also assume that all accidents and violations occurred between 2 and 5 years ago, i.e., that none of them were in the past two years.
Vehicle Assumptions: 1. All vehicles identified in the estimate are each driven at least 7,500 miles annually. (CA and CO, and/or other states as appropriate: 12,000 miles annually), and were purchased in the same year as the model year. 2. All vehicles identified in the estimate are driven to and from work (less than or equal to 20 miles each way). If the consumer is 55 or older and retired, it's assumed the vehicle driven is driven solely for pleasure. 3. Unless otherwise noted, coverages and deductibles selected will apply to each vehicle. 4. The estimate is based on the year, make, and model of the vehicle and does not consider the specific sub-model details.
Personal Assumptions: 1. If the consumer indicates that he or she owns his or her primary residence, it's assumed to be a single family home or condominium. 2. The insurance score assumed for this estimate is based on the consumer's self-assessment of General Bill Payment History. 3. Continuous insurance coverage is assumed to have been with the same insurance carrier and not with multiple insurance carriers. Carrier is assumed to be a “standard” insurance company. 4. If the consumer indicates that s/he currently carries auto insurance, it is assumed the limits of the Bodily Injury Liability coverage are equivalent to the most popular limits among customers in the consumer's state ($100,000 per person/$300,000 per accident in most states).
Steps 201 - 205 may be performed in any order, or may be combined or split into further levels of granularity. For example, assumptions may be determined prior to selecting the rate factors to use in the estimation process, or the assumptions and selection may be performed at the same time.
In step 207 a user, e.g., a prospective insurance purchaser, provides input to rate server software 125 (e.g., via web server 105 ) for each of the selected rate factors. The input is provided according to the value input filter corresponding to each selected rate factor. Then, in step 209 , the rate server 103 determines an estimated amount of an insurance premium for the consumer based on information stored in the rate model 129 . Step 209 may include determining one estimate or a range of insurance estimates based on a variety of options the user may select as part of the insurance product. For example, estimates may be provided for varying levels of protection ($100K, $250K, $500K, etc.), varying deductibles, with and without collision insurance, and/or any other options the user may be able to select.
In step 211 the estimate or estimates are presented to the user. When multiple estimates are presented to the user, the estimates are preferably presented in a dynamic format or media so the user can explore the assumptions and/or options associated with each estimate. According to an illustrative embodiment, the range of estimates may be presented in a grid where each successive row provides an estimate associated with an increasing level of insurance coverage (e.g., $25K/$50K, $100K/$300K, and $250K/$500K), and each column provides an estimate associated with an increasing number of add-on options associated with the insurance coverage (e.g., accident forgiveness, Deductible Rewards SM , Safe Driving Bonus SM , etc.).
According to an illustrative embodiment, automobile insurance estimates may be provided in a grid reflecting the following insurance levels (Collision Deductible, Comprehensive Deductible, Bodily Injury limits, Property Damage limit, Medical Payment limit, Uninsured Motorist limits) and add-on options.
TABLE 2
Sample Grid of Insurance Levels and Add-Ons
Coll.
$500
$500
$500
$500
Deduct.:
Compr.
$500
$500
$500
$500
Deduct.:
Bodily
$25K/
$25K/
$25K/$50K
$25K/$50K
Injury:
$50K
$50K
Prop.
$20K
$20K
$20K
$20K
Damage:
Medical:
None
None
None
None
Uninsured
$25K/
$25K/
$25K/$50K
$25K/$50K
Motor.:
$50K
$50K
Bonus
Direct
Accident
Accident
Accident
Features
Deposit
Forgiveness
Forgiveness
Forgiveness
Payments
Deductible
Safe Driving
Rewards SM
Bonus SM
Deductible
Rewards SM
Coll.
$500
$500
$500
$500
Deduct.:
Compr.
$500
$500
$500
$500
Deduct.:
Bodily
$100K/
$100K/
$100K/$300K
$100K/$300K
Injury:
$300K
$300K
Prop.
$100,000
$100,000
$100,000
$100,000
Damage:
Medical:
$1,000
$1,000
$1,000
$1,000
Uninsured
$100K/
$100K/
$100K/$300K
$100K/$300K
Motor.:
$300K
$300K
Bonus
Direct
Accident
Accident
Accident
Features
Deposit
Forgiveness
Forgiveness
Forgiveness
Payments
Deductible
Safe Driving
Rewards SM
Bonus SM
Deductible
Rewards SM
Coll.
$500
$500
$500
$500
Deduct.:
Compr.
$500
$500
$500
$500
Deduct.:
Bodily
$250K/
$250K/
$250K/$500K
$250K/$500K
Injury:
$500K
$500K
Prop.
$200,000
$200,000
$200,000
$200,000
Damage:
Medical:
$2,000
$2,000
$2,000
$2,000
Uninsured
$250K/
$250K/
$250K/$500K
$250K/$500K
Motor.:
$500K
$500K
Bonus
Direct
Accident
Accident
Accident
Features
Deposit
Forgiveness
Forgiveness
Forgiveness
Payments
Deductible
Safe Driving
Rewards SM
Bonus SM
Deductible
Rewards SM
Using the above method, users can self declare non-personally identifying information to obtain an estimated amount for an insurance premium, thereby allowing the consumer to remain anonymous. The consumer can then select from a range of insurance packages at varying price points that reflect a broad range of insurance services offered, and the consumer can select the choice that most closely reflects his or her current needs.
Beginning with FIG. 3 , a sample user interface available to consumers over the Internet will now be described. The user interface comprises many different screens as shown below, and may be exposed to the user via web server 105 , with resultant estimates computed by rate server 103 . Other system architectures may of course be used.
In FIG. 3 , web server 105 displays a first screen 301 providing a general introduction to the consumer, and requesting initial basic information 303 , 305 , 307 . The user inputs his or her zip code 303 , the type of insurance 305 for which the user desires to obtain an estimate, and whether the user wants to start a new quote or continue a saved quote in option box 307 . Upon entering the information, the web server may display optional screen 401 ( FIG. 4 ) to provide additional information to the user while loading subsequent information, e.g., java, flash, or other applet code or software to the user's client computer 107 or 109 at the direction of web server 105 .
When the user is ready to begin, the user selects start button 403 and proceeds to user interface 501 illustrated in FIG. 5 . In FIG. 5 , user interface 501 is presently displaying information regarding Drivers tab 503 , through which the user can enter driver information. Other available tabs, discussed further below, include a Vehicles tab 505 , Background tab 507 , and Pick a Plan tab 509 . The user selects Add button 511 to add a driver to the estimate, and Next button 513 to move to the next tab. The user at any time can select or hover over the Assumptions control 515 to learn what assumptions are being made during the estimation process, e.g., Driver Assumptions 1703 , Vehicle Assumptions 1705 , and Personal (aka, Background) Assumptions 1707 , through an assumptions user interface 1701 , illustrated in FIG. 17 .
With reference to FIG. 6 , upon selecting Add button 511 , web server 105 displays selection list 603 for the user to select gender and marital status of the driver to be added to the insurance quote. As used herein, when web server 106 is indicated as performing some function, that function may be performed by web server 105 directly, or may be performed by software downloaded from web server 105 to the user's computer 107 and executing on the user's computer 107 , e.g., a java module, Flash or Shockwave program, etc. Upon selecting one of the gender/marital status options, the user is prompted to enter the driver's age and driving history as illustrated in FIG. 7 .
FIG. 7 illustrates user interface 501 for the Driver tab 503 , which now indicates that one (1) driver has been added. User interface 501 also displays an Age input control 703 and Driving History input control 705 . Each input control may be any type of user input device, e.g., slider bars, drop down lists, radio buttons, check boxes, text boxes, etc. Here, input controls 703 , 705 are sliders, where each position on the slider corresponding to a valid input as defined by the value input filter corresponding to the rate factor for which input is sought. In the case of Age input control 703 , the user can slide the slider ball 704 until the desired age is displayed above the ball 704 (here, the selected age of 35 is displayed above the slider ball 704 ). Next, the user selects the driving history 705 that best corresponds to the driver. The allowable options, again defined by a value input filter, are 0, 1, and 2+, selectable via slider ball 706 . On each screen, supplementary information corresponding to the active input control may displayed in information area 707 . When the user is satisfied with the input, as confirmed in sidebar 709 , the user selects Next button 513 .
In FIG. 8 user interface 501 now displays the Vehicles tab 505 . The Vehicles tab 505 is the screen through which the user enters information regarding each of the vehicles that is to be insured. The user can select Add button 803 to add a vehicle to the estimate, or Next button 805 when done entering vehicle information to move on to the next tab. Upon selecting Add button 803 , user interface 501 displays vehicle information input controls 903 , 905 , 907 , as illustrated in FIG. 9 . In FIG. 9 , user interface 501 displays Vehicle Year input control 903 , Vehicle Make input control 905 , and Vehicle Model input control 907 . Each input control can be any variety of input control, including drop down lists, radio boxes, text input boxes, constrained lists, etc., as are known in the art. In this illustrative embodiment, input controls 903 , 905 , 907 are drop down lists from which a user can select valid input values as defined by the value input filters corresponding to each of the Vehicle Year input control 903 , Vehicle Make input control 905 , and Vehicle Model input control 907 . The user can confirm the information input via sidebar 911 , which displays the input information for each vehicle entered as part of the quote process. User interface 501 also updates Vehicles tab 505 to indicate the number of vehicles that have been added (here, one). Upon completion of entering all desired vehicles, for example as illustrated in FIG. 10 where two vehicles have been entered by the user, the user selects Next button 805 to proceed.
FIG. 11 illustrates user interface 501 displaying the Background tab 507 . The Background tab 507 is the screen through which the user enters background information regarding each of the drivers input via the Driver tab 503 ( FIG. 7 ). Background tab 507 includes Residence input control 1103 , Bill Payment History input control 1105 , and Insurance History input control 1107 . Each input control can be any variety of input control, including drop down lists, sliders, radio boxes, text input boxes, constrained lists, etc., as are known in the art. In this illustrative embodiment, input controls 1103 , 1105 , 1107 are sliders which a user can manipulate into a position corresponding to the desired input value. The slider positions are constrained to valid input values as defined by the value input filters corresponding to each of the Residence input control 1103 , Bill Payment History input control 1105 , and Insurance History input control 1107 . Additional information regarding the active input control may be displayed in information area 707 . After entering the requested information, the user selects Next button 1109 , which sends the last of the required information to web server 105 and rate server 103 for processing.
After rate server 103 has processed the information and compared the information to rate model 129 using any desired rate model, rate server sends rate information to web server 105 for presentation to the user via output grid 1201 displayed in the Pick a Plan tab 509 of user interface 501 , e.g., as illustrated in FIG. 12 . The output grid 1201 , in this illustrative embodiment, displays estimated 6 month premiums corresponding to the levels of insurance and add-ons shown in Table 2, above. When the user hovers over one of the grid entries with his or her mouse, additional information is displayed via popup interface 1301 , illustrated in FIG. 13 with respect to the Enhanced Value Package and in FIG. 14 with respect to the Enhanced Plus Platinum Package. Also as illustrated in 1303 , when the user hovers over a row, a drop down arrow 1303 may be displayed corresponding to the packages in that row. Upon selection of drop down arrow 1303 , detailed descriptive information 1502 common to all packages within that row may be displayed, for example as illustrated in FIG. 15 .
FIG. 16 illustrates informational screen 1601 which may be displayed when the user selects one of the provided estimates, here the Gold Package with Enhanced Plus (i.e., the Gold Package column and Enhanced Plus row of the grid). The estimation process is now complete, and the user can proceed to obtain a firm quote, e.g., from a local agent, via input button 1603 , print the estimate via input control 1605 , or cancel and return to the grid via input control 1607 .
At any point during the above process the user can roll/hover over informational icons, appearing in this illustrative embodiment as question marks in parentheses “(?)” displayed on the various user interface screens, to obtain additional information regarding the item next to which the informational icon (?) appears. Also at any time during the process the user can reset all the information entered so far via Reset input control 517 ( FIG. 5 ), or cancel out of the entire process via Cancel input control 519 ( FIG. 5 ).
FIG. 18 illustrates the method depicted in FIGS. 3-17 . Initially, in step 1801 , as illustrated in FIG. 3 the rate server obtains the desired geographic location of coverage, e.g., via a user interface provided to the user via web server 105 and client computer 107 or 109 . Next, in step 1803 , the user inputs the gender and marital status for the first driver. The gender uses the value input filter [male, female], and marital status uses the value input filter [single, married]. According to some embodiments, gender and marital status may be provided simultaneously. In step 1805 the user provides the age and driving history for the first driver. Age is provided according to a value input filter of [16, 17, . . . , 54, 55+], and driving history uses the value input filter [0, 1, 2+]. Steps 1803 and 1805 are illustrated in FIGS. 5-7 . If there are additional drivers to be insured, the method returns back to step 1803 to obtain driver information for each additional driver from the user.
In step 1807 the user provides the year, make, and model for each vehicle to be insured. The vehicle year is preferably provided first according to a value input filter similar to [1970, 1971, . . . , <present year>]. The make is then selected from a value input filter that includes all manufacturers that manufactured an insurable car during the selected year. The model is selected from a value input filter that includes all insurable models manufactured by the selected manufacturer. Step 1807 is illustrated further in FIGS. 8-10 .
In step 1809 the system obtains residence information from the user, indicating whether the user owns or rents (or neither) his or her home. The value input filter [own, rent, neither] may be used. In step 1811 the user provides a self declaration of bill payment history based on a value input filter similar to [Excellent, Very Good, Good, Fair, Poor], and in step 1813 provides a self declaration of prior insurance history. The prior insurance history may be entered according to the value input filter [0, 0.5, 1, 2, 3+, 5+, 10+], where the selected value is in years. Steps 1809 - 1813 are illustrated further in FIG. 11 . Allowing users to self-declare information helps to alleviate privacy concerns, because the user is not required to authorize the insurer to obtain personal information from alternative sources.
After the user completes the data entry portions of the process, the rate server in step 1815 generates one or more insurance estimates based on the received information, and displays the generated estimate(s) to the user via a user interface, e.g., an interactive dynamic user interface as illustrated in FIGS. 12-17 . If the user desires to obtain another estimate, the method may return to step 1801 , otherwise the estimation process ends. The steps illustrated in FIG. 18 may be reordered, combined, or split, without affecting the usability of the data. In addition, the data may be obtained via a user interface, or may be manually entered by an employee of the insurer (e.g., a customer service representative) based on verbal information given to the employee by the user over the phone, via written information received on an estimate inquiry form, or via other communication media.
Although the subject matter has been described in language specific to structural features and/or methodological acts, it is to be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.
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Methods and systems for providing estimated insurance quotes/premiums are described herein. After analyzing rate factors, a subset of rate factors are selected that yield a fairly accurate estimated insurance premium from a minimum amount of information easily obtainable from a user. The user inputs a value from a predetermined set of allowable inputs (value input filter). After receiving and analyzing the user inputs, the system generates one or more estimates and displays the one or more estimates to the user, e.g., via a web page. When multiple estimates are provided, the multiple estimates may differ based on the level of coverage, add-on features, or both. Readily known non-personal identifying information is preferably requested and used, thereby alleviating privacy concerns while still being able to provide an estimate to the user very quickly, e.g., under 30 seconds, once all the requested information is obtained.
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CROSS-REFERENCE TO RELATED APPLICATION(S)
This application is a continuation-in-part of U.S. application Ser. No. 13/758,408, now U.S. Pat. No. 9,365,801, filed Feb. 3, 2013 and entitled “Process of Converting Low and High Free Fatty Acid Containing Oils Into No Free Fatty Acid Containing Oils,” which is hereby incorporated by reference in its entirety under 35 U.S.C. §119(e).
TECHNICAL FIELD
The disclosure relates generally to oils for use as biodiesel feedstock and, more particularly, to improved processes and systems for refining low free fatty acid oils and high free fatty acid oils for use as biodiesel feedstock.
BACKGROUND
Biodiesel, defined as fatty-acid alkyl ester (“FAAE”), is most commonly produced by a process of trans-esterification of triglycerides. The process involves reacting oils and fats with alcohol, usually methyl alcohol, in the presence of an alkaline catalyst. The conversion of triglycerides with alkaline catalysis is described in U.S. Pat. Nos. 2,383,601 and 2,494,366. The process is most efficient when the feedstock is a pure glyceride (refined oils and fats) containing very low levels (typically lower than 1%) of free fatty acids (“FFA” which, for all practical purposes, is called a “No” FFA (“NFFA”) oil. Unfortunately, the price of NFFA oil has increased dramatically over the last several years rendering it impossible to produce biodiesel from such feedstocks and compete with petro-diesel. While cheaper feedstocks are available, they contain impurities (including greater than 1% FFAs) that require additional processing, thus increasing the cost of producing biodiesel. The challenge is to develop processes that can convert oils containing higher than 1% FFA into NFFA oils; thus producing a cheaper feedstock for producing biodiesel.
The literature includes a number of approaches of dealing with FFA (see, Tyson, Shaine K., “Brown Grease Feedstocks for Biodiesel,” 2002, pp. 1-34, National Renewable Energy Laboratory, Boulder, Colo.) (www.nrbp.org/pdfs/pub32.pdf). One of the options is to strip the FFAs from the oil. This is a well-known process, also known as physical refining or steam distillation. In this process, the FFA is stripped (evaporated) from the oil under vacuum. The FFA is condensed and recovered. The advantage of this process is that it produces oil that is practically free of FFAs and a very good feedstock for producing biodiesel. A challenge with this process is that there is a reduction in the amount of oil available to produce biodiesel due to loss of FFA and some neutral oil during the stripping process. Consequently, the higher the FFA the higher the yield loss and the lower the attractiveness of this approach. An example of this process of recovering fatty acids is set out in U.S. Pat. No. 6,423,857. This patent focuses on pre-treating high phospholipid containing oil (such as soybean oil) prior to steam distillation and subjecting the oil to steam distillation that produces a distillate containing at least about 97 percent by weight free fatty acids. It is well-known that soybean oil typically contains only about 0.6% FFA, therefore the losses are limited. With higher FFA oils, the losses will be greater.
Another option is to react the FFAs with an alcohol, usually methyl alcohol, in the presence of an acid catalyst to produce FAAE. For instance, U.S. Pat. No. 4,164,506 discloses a biodiesel synthesis wherein fatty acids are subjected to acid catalysis. This process is called acid esterification and would be very attractive if it could convert all FFA into FAAEs. Unfortunately, this process poses several challenges: (a) un-reacted or unconverted FFA left in the oil after esterification must be removed with additional intermediate steps and equipment; (b) the esterification process requires use of acidic catalyst which poses risk to people (risk of burning skin and flesh upon contact) as well as equipment (risk of corrosion upon contact); and (c) the esterification process requires a large quantity of excess methanol (needed to maintain the proper equilibrium for advancing the reaction which is inhibited by the formation of water during esterification) thus increasing the emission of volatile substance in the atmosphere. The acid esterification is especially unattractive when the FFA content is higher because a large amount of acid catalyst and methyl alcohol are required in order to convert feedstocks having high FFA content. Since the acid catalyst must be neutralized with alkali before processing the glycerides, the increased catalyst loading results in an excessive amount of salts produced as a consequence of alkali neutralization. Further, such processes generate a large volume of waste water as revealed in the disclosures of U.S. Pat. Nos. 4,303,590, 5,399,731 and 6,399,800.
Alternatively, solid catalysts can be used for the acid esterification reaction to avoid a neutralization step before the transesterification reaction. These processes have been extensively explored and documented, such as in U.S. Pat. No. 3,459,736 (which uses titanium oxide as a catalyst), U.S. Pat. No. 4,698,186 (which utilizes various solid catalysts), U.S. Pat. No. 4,267,393 which uses sulfonated resins as solid acid catalysts and U.S. Pat. No. 5,908,946 which employs zinc and aluminum oxide as catalysts for the esterification reaction).
U.S. Pat. Appl. No. 2003/0083514 discloses a single-phase process for production of fatty acid methyl esters from mixtures of triglycerides and fatty acids. This process is limited in that it requires acid catalyzed esterification of fatty acids prior to the transesterification step. U.S. Pat. No. 2,383,596 discloses a method for esterifying fatty acid and trans-esterifying glycerides. This process is limited in that only an esterification step is disclosed.
A third option is enzymatic catalysis. The conversion of both free fatty acids and triglycerides with enzyme catalysis is disclosed in U.S. Pat. Nos. 4,956,286, 5,697,986 and 5,713,965. A representative example of the esterification or transesterification method is disclosed in JP-B 6-65311, in which fatty acids or lower alcohol esters thereof are reacted with glycerol (or glycerin) in the presence of an immobilized lipase having 1,3-position selectivity and the by-product water or lower alcohol formed by the reaction is removed from the system at a reduced pressure to obtain the diglycerides. This reaction is preferably conducted in the presence of an enzyme having an ester activity, such as a lipase or an esterase, preferably in the presence of an immobilized or intracellular lipase having 1,3-position selectivity. Known methods for immobilization are described, for example, In “Koteika Koso (Immobilized Enzyme),” edited by Ichiro Chihata, published by Kodansha Ltd. Publishers, pp. 9-85 and “Koteika Seitai-shokubai (Immobilized Biocatalyst)” edited by Ichiro Chihata, published by Kodansha Ltd. Publishers, pp 12-101. Immobilization onto an ion-exchange resin is preferred. Lipases having 1,3-position selectivity and usable in immobilization include those derived from microorganisms of, for example, the genera Rhizopus, Aspergillus, Mucor , etc., as well as pancreatic lipases, and the like. For example, use can be made of the lipases derived from Rhizopus delemar, Rhizopus japonicus, Rhizopus niveus, Aspergillus niger, Mucor javanicus , and Mucor miehei . A commercial immobilized lipase having 1,3-position selectivity is Lipozyme® IM, manufactured by Novo-Nordisk Bioindustry A.S. An intracellular lipase having 1,3-position selectivity comprises a lipase having 1,3-position selectivity adsorbed or bonded to microbial cells. A commercially available example thereof is Olipase™, manufactured by Nagase & Co., Ltd.
This process is challenging because the reaction produces water which inhibits the forward reaction. Other problems with enzymatic processing are the slow reaction rates and high cost of enzymatic catalysts. Further, enzymatic catalysts have a limited life. These shortcomings when compared to alkaline and acidic reactions render the enzymatic processes economically unfavorable.
A fourth option is described in US Pat. Appl. No. 2012/0123140 involving glycerolysis of high free fatty acid (HFFA) oil. This process converts FFAs into oils through esterification of fatty acids with glycerol. The resulting product is oils which are fatty acid glycerin esters (or FAGE). This process is variously known as glycerolysis, alcoholysis, or esterification. Glycerolysis of fats and oils with glycerol has been intensively researched during the 1940's and 1950's. Sonntag (1982) (Sonntag, N.O.V., glycerolysis of Fats and Methyl Esters—Status, Review, and Critique, Journal of American Oil Chemists Society 59:795A-802A) has a complete collection of these patents in his review. The reaction produces a mixture of mono-, di- and tri-glycerides.
For example, U.S. Pat. No. 3,102,129 discloses a process for producing monoglycerides of fatty acids and U.S. Pat. No. 2,875,221 discloses a process for preparing monoglycerides of fatty acids. These processes are limited in that they require admixing a substantial proportion of previously reacted monoglyceride product with a freshly mixed stream of glycerol and fat and rapidly heating the mixture on a hot surface. U.S. Pat. No. 6,500,974 discloses a process for preparation of a monoglyceride. This process is limited in that the presence of a food grade polar solvent is required in the glycerolysis reactor.
Although the esterification or transesterification method is a process in which fatty acids or lower alcohol esters thereof and glycerol are converted to partial diglycerides through a one-step reaction, it is not cost efficient because the individual feedstock materials are expensive. For conducting the second stage esterification reaction, glycerol is added to the partial decomposition product, obtained through the first-stage reaction in such an amount that the mole number of fatty acid groups in the decomposition product mixture of the first stage is from 0.8 to 2.5 mol per 1 mol of glycerol groups based on the total of glycerol groups of the decomposition product mixture of the first stage and glycerol groups added to the second stage (see, e.g., U.S. Pat. No. 6,261,812).
On the other hand, U.S. Pat. No. 2,808,421 discloses a method for preparing mixed triglyceride compositions using a titanium alcoholate catalyst. U.S. Pat. Nos. 7,806,945, 8,088,183, 7,871,448, and US. Pat. Appl. No. 2012/0123140, disclose a process for preparation of fatty acid methyl ester using HFFA oil. The process includes glycerolysis as part of their overall process. The conditions taught for glycerolysis of free fatty acids (at a temperature of about 220° C. and at a pressure of about 2 pounds per square inch absolute) in a glycerolysis reaction without a catalyst to produce a glycerolysis reactor effluent stream that contains less than 0.5 percent by weight of free fatty acids and a plurality of glycerides, are similar to other literature. These patents teach there is a need for at least two continuous stirred tank reactors that are operated in series with a combined residence time of not more than about 500 minutes. For a 20% FFA stream, the time taken is no more than 200 minutes. A problem with this approach is that, despite claims to the contrary, it only efficiently reduces the FFA by 80-90%, thus making it necessary to either use catalysts or add intermediate steps and equipment to reduce the remaining FFA either chemically or physically. Moreover, the size of glycerolysis reactors is large because it is sized to handle the entire mass of oil even though the FFA content is a relatively small portion of that stream and consequently there is a waste of energy because a greater amount of material (the entire HFFA oil stream) is subject to higher temperature and then cooled down when it is only necessary to heat the FFA.
The background art is also characterized by a number of non-patent publications. Noureddini et al. in glycerolysis of Fats and Methyl Esters , JAOCS, 1997, pp. 419-425, vol. 74, no. 4 discloses the glycerolysis of methyl esters and triglycerides with crude glycerin. The main focus of their study is on utilization of “crude” glycerol obtained from the biodiesel industry as opposed to “pure” glycerin previously used in glycerolysis to mono-, di-, and tri-glycerides. They did not disclose glycerolysis of fatty acids and their focus was on production of mono- and di-glycerides from FAME and tri-glycerides using crude glycerin.
Felizardo, et al. in “Study on the glycerolysis reaction of High Free Fatty Acid Oils for Use as Biodiesel Feedstock”, Fuel Processing Technology, 2011, pp 1225-1229, vol 92, no. 6, discloses the conversion of oils with a high content of FFA (20-50%) by esterification with glycerol. The results suggest that the FFA content could be reduced from 50% to 5% in 3 hours at 200° C. without the use of a catalyst. The presence of a zinc-based catalyst reduced the reaction time to 1 hour and reduced the FFA to 1.2%.
Canakci, M. and J. Van Gerpen (2001) in Biodiesel Production from Oils and Fats with High Free Fatty Acids, Transactions of the American Society of Agricultural Engineers, 44(6):1429-1436 discloses that “glycerolysis” is an alternative process that can be used with feedstocks containing more than 10% FFAs. This involves adding glycerin at 400° F. and letting it react with the FFAs to form monoglycerides, a glycerol molecule to which one free fatty acid has been joined. These monoglycerides can then be processed using a standard alkaline catalyst transesterification process. Waste glycerin from biodiesel processing can be used in this process. Glycerolysis can be expensive because of the high heat involved, which requires a high-pressure boiler and trained boiler operator. Also, a vacuum must be applied while heating to remove water that is formed during the reaction. Another disadvantage is that the glycerin will also react with the triglycerides in the oil to convert some of them to monoglycerides. While this does not negatively impact the reaction, it means that more glycerin is required for the process, and therefore more glycerin must be removed at the end of the transesterification.
Kumoro in “Experimental and Modeling Studies of the Reaction Kinetics of Alkaline-Catalyzed used Frying Oil Glycerolysis using Isopropyl Alcohol as a Reaction Solvent, Research Journal of Applied Sciences, Engineering and Technology 4(8): 869-876, 2012, discloses a glycerolysis process using isopropyl alcohol and an alkaline catalyst. However, the focus of this and several other research is to convert tri-glycerides to mono-glycerides for use in foods, cosmetics, and pharmaceutical products. This study is not directly relevant to our invention because it does not address glycerolysis of fatty acids.
Tyson in Brown Grease Feedstocks for Biodiesel, WWW domain nrel.gov, 2002, pp. 1-33, National Renewable Energy Laboratory, Boulder, Colo., discloses techniques for converting greases to biodiesel. The techniques disclosed in this reference are limited. Moreover, the conditions taught for glycerolysis of free fatty acids are at temperatures in the range of 250° C. to 260° C. in the absence of a catalyst or at 220° C. with a catalyst. The reference teaches that there is “no proven technology for 50+% FFA mixes” and that “combined processes for ASTM [American Standard for Testing and Materials] quality biodiesel not well developed, technical and economic questions exist.”
Tyson in Biodiesel Technology and Feedstocks, WWW domain nrel.gov, 2003, pp. 1-37, National Renewable Energy Laboratory, Boulder, Colo., includes much of the same information as contained in her 2002 presentation. The reference notes that using “glycerolysis to treat FFA” to “convert FFA to monoglycerides, then transesterify” is “commercial, not currently used in biodiesel.”
Davis Clements in Pretreatment of High Free Fatty Acid Feedstocks, Biodiesel Production Technology Workshop III, Mar. 26-28, 2003, pp. 78c-78i, University of Nebraska, Lincoln, Nebr., discloses a number of methods for pretreatment of high free fatty acid feedstocks prior to transesterification. This process is limited in that glycerolysis is carried out at 200° C. under an 11 pounds per square inch vacuum, usually with a catalyst such as zinc chloride, with venting of water. This process is further limited in that, in the absence of a catalyst, a residence time of over 5 hours is required to achieve an effluent containing less than 1 percent free fatty acids.
BRIEF SUMMARY
We have listed the prior art and their merits and problems. Moreover, the goals of many prior art works pertaining to glycerolysis have been different. One stream of research has addressed the conversion of tri-glycerides to mono-glycerides for the purpose of producing emulsifiers used in foods, cosmetics, and pharmaceutical products. On the other hand, the goal of converting fatty acids to glycerides is more relevant to the disclosed systems and methods. Therefore, the attempt of the prior art has been to obtain close to full conversion of fatty-acids to glycerides. The goal of the disclosed systems and methods in the glycerin-esterification (glycerolysis) step is not to achieve full conversion of FFA into glycerides but rather to achieve about 80-95% conversion of FFA into glycerides. This can be achieved without the use of any catalyst and with less energy input. The glycerolysis is then coupled with FFA stripping to remove the remaining FFA to produce oil containing less than about 0.5% FFA or less than about 1.0% FFA. This combination of glycerin-esterification and subsequent stripping results in greater consistency of the final product.
Moreover, this combination process allows the flexibility to process Low Free Fatty Acid (“LFFA”) and High Free Fatty Acid (“HFFA”) oils in different ways to produce NFFA oils. Specifically, the disclosed systems and methods processes LFFA (containing from about 1% up to about 20% FFA) oil to an oil containing less than 1.0% FFA. This is accomplished by stripping the FFA from LFFA oil. The recovered FFA (which may have a concentration greater than 20% FFA) is then treated with glycerol to convert into glycerides (oil). The glyceride stream will contain 1-10% or more, up to 20% FFA that is returned to the front of the stripping process to remove the remaining FFA. This forms a closed loop wherein none of the FFA is wasted. In this implementation, the FFA remains in a closed loop where it is stripped from the LFFA oil and converted to glycerides by glycerolysis. Next, the oil returns to blend with the incoming LFFA oil. The resulting oil stripped of FFA that leaves the loop has less than about 0.5% FFA or less than about 1.0% FFA, and that is the product of interest. The disclosed systems and methods is a novel process for the conversion of HFFA oil (containing up to 100% FFA) to an oil containing as little as less than about 0.5% FFA or less than about 1.0% FFA. Through this novel combination process, these low-grade fatty materials that previously could not be utilized by existing processes are refined to biodiesel-ready feedstock by means of the invention disclosed herein. Since the cheapest feedstocks are the ones that have the highest FFA content, there is a need for a process that does not entail the shortcomings of existing processes described above. Such processes also need to reduce waste and energy consumption while increase yield. Further, the disclosed systems and methods combines several unit operations into an economical and unique process for the conversion of LFFA and HFFA to NFFA oils without wasting FFAs. The invention allows biodiesel producers to use NFFA feedstock.
One general aspect includes a method for producing oil having less than 1.0% free fatty acids from oil containing between about 1.0-20% free fatty acids, including the steps of purifying a stream of oil containing up to about 20% free fatty acid by steam distillation, where steam is used to strip the free fatty acids and produce a first stream of oil containing more than about 20% free fatty acid and a second stream of oil containing less than about 1.0% free fatty acid; recovering stripped fatty-acids from the first stream through condensation; reacting the recovered stripped free fatty acids with glycerin to produce glycerin-esterified oil containing about 0.2-20% free fatty acids; mixing the glycerin-esterified oil with the about 1.0-20% free-fatty acid containing oil and stripping the free fatty acids from the glycerin-esterified oil by steam distillation; recirculating any recovered free-fatty acids; and separating oil containing less than about 1.0% free fatty acid.
Implementations may include one or more of the following features. The method where deaeration of oil is performed at between about 70C and about 120C. The method further including pre-heating the stream of oil with hot refined oil in a series of economizers. The method further including flashing the pre-heated oil in a pre-distiller at between about 180 C and about 300 C. The method further including flashing the pre-heated oil in a pre-distiller at between about 1 mm and about 10 mm pressure. The method where to the steam stripping occurs at between about 180 C and about 300 C. The method where the stream oil is subject to steam stripping at between about 1 mm and about 10 mm pressure. The method where the stripped free fatty acid is recovered by condensing. The method further including collecting the purified free fatty acid in a fatty acid collection tank. The method where the recovering stripped fatty-acids from the first stream through condensation is performed at between about 160C and about 300C. The method recovering stripped fatty-acids from the first stream through condensation is performed on recovered FFA at a pressure of between about 10 mm to about 150 mm. The process further including reacting the recovered free fatty acids with glycerin to produce a fourth stream of oil. The system where the system is configured to react the stripped free fatty acids with glycerin at high temperature and low pressure to produce oil with up to about 20% free fatty acids. The system further including a scrubber configured to utilize cooled free fatty acids to scrub additional free fatty acid from steam vapors. The system where the free fatty acid stripper is configured to strip the free fatty acids from the oil by injecting steam at an elevated temperature and reduced pressure. The system further including a vacuum system. The system further including a first condenser configured to condense glycerol. The system further including a second condenser configured to condense water.
One general aspect includes a fatty acid stripping process, including: reacting the oil containing about 10-100% free fatty acids with glycerin to produce a stream of oil having up to about 20% free fatty acids; purifying the stream of oil having up to about 20% free fatty acids by steam distillation, where steam is used to strip the remaining free fatty acids and produce: a stream of oil that contains greater than 20% free fatty acid; and a stream of oil that contains less than 1.0% free fatty acid; recovering stripped free fatty acids from the stream of oil that contains less than 1.0% free fatty acid through condensation; mixing the stripped free-fatty acids with about 10-100% free-fatty acid containing oil and reacting the resulting stream with glycerin to produce a stream of oil having up to about 20% free fatty acids; recycling the stripped free fatty acids; and recovering a final oil having less than about 1.0% free fatty acid.
Implementations may include one or more of the following features. The process further including reacting the recovered free fatty acids with glycerin to produce a fourth stream of oil. The system where the system is configured to react the stripped free fatty acids with glycerin at high temperature and low pressure to produce oil with up to about 20% free fatty acids. The system further including a scrubber configured to utilize cooled free fatty acids to scrub additional free fatty acid from steam vapors. The system where the free fatty acid stripper is configured to strip the free fatty acids from the oil by injecting steam at an elevated temperature and reduced pressure. The system further including a vacuum system. The system further including a first condenser configured to condense glycerol. The system further including a second condenser configured to condense water.
One general aspect includes A system for producing oil having less than about 1.0% free fatty acids from an oil containing up to 100% free fatty acids, including: a reactor configured to react oil containing up to 100% free fatty acids with glycerin in the absence of a catalyst at high temperature and low pressure to produce a stream of oil having up to about 20% free fatty acids; a pre-distiller configured to purify the oil having up to about 20% free fatty acids by steam distillation at high temperature and low pressure; a free fatty acid stripper configured to steam-strip free fatty acids and produce oil having less than about 1.0% free fatty acids; and stripped free fatty acids; a fatty acid collection tank configured to recover the stripped free fatty acids through condensation; and a storage tank configured for collecting and storing oil having less than about 1.0% free fatty acids.
Implementations may include one or more of the following features. The system where the system is configured to react the stripped free fatty acids with glycerin at high temperature and low pressure to produce oil with up to about 20% free fatty acids. The system further including a scrubber configured to utilize cooled free fatty acids to scrub additional free fatty acid from steam vapors. The system where the free fatty acid stripper is configured to strip the free fatty acids from the oil by injecting steam at an elevated temperature and reduced pressure. The system further including a vacuum system. The system further including a first condenser configured to condense glycerol. The system further including a second condenser configured to condense water.
While multiple embodiments are disclosed, still other embodiments of the disclosure will become apparent to those skilled in the art from the following detailed description, which shows and describes illustrative embodiments of the disclosed apparatus, systems and methods. As will be realized, the disclosed apparatus, systems and methods are capable of modifications in various obvious aspects, all without departing from the spirit and scope of the disclosure. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature and not restrictive.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic flow diagram of the process of glycerin esterification and FFA stripping, according to an exemplary embodiment.
FIG. 1A is an expanded, detailed view of the upper left quarter of FIG. 1 .
FIG. 1B is an expanded, detailed view of the upper right quarter of FIG. 1 .
FIG. 1C is an expanded, detailed view of the lower left quarter of FIG. 1 .
FIG. 1D is an expanded, detailed view of the lower right quarter of FIG. 1 .
FIG. 2 is a flowchart showing steps for converting low FFA oils to no-FFA oils, according to an exemplary embodiment.
FIG. 3 is a flowchart showing steps for converting high FFA oils to no-FFA oils, according to an exemplary embodiment.
DETAILED DESCRIPTION
EXAMPLE 1
LFFA Oil (i.e., Oil Containing Up to about 1-20% FFA)
Step-1: As shown in FIGS. 1-2 generally at 10 and 100 , the low free fatty acid (“LFFA”) process according to certain implementations includes a FFA stripping step wherein LFFA oil (1-20% FFA by wt %) is first stripped of FFA. With reference to FIGS. 1A-D , the LFFA oil (shown in FIG. 2 at box 102 ) is pumped out of the low fatty acid tank 12 by a pump 14 through a start-up heater 16 to a deareator 18 . In this implementation, the deareator 18 is configured to remove any air or moisture contained in the feedstock (shown in FIG. 2 at box 104 ). In various implementations, the deaerator 18 operates at temperature of 70° C.-120° C. (preferably between 80-100° C.) and a pressure of 25-200 mm Hg absolute depending upon the moisture content (preferred between 50-75 mm). The deaerator 18 is in sealed fluidic and hermetic communication with the vacuum system 80 to regulate the pressure inside the deaerator 18 (shown in FIG. 2 at box 106 ).
The deaerated-oil is pumped by pump PU-707 20 through a series of economizers 22 , 23 , 24 , and (by way of line 25 ) 26 , prior to being pumped (along line 27 ) into a pre-distiller 30 for pre-distillation (box 108 ). In this implementation, the temperature is raised to between 180° C.-300° C. (preferably between 230-280° C.) at a pressure of 1-10 mm Hg absolute (preferred between 3-5 mm) by hot oil or other means which could be electric or high-pressure steam. Steam is infused to act as a carrier of fatty acids vapors (box 110 , line 109 ).
In certain implementations, the majority of the FFA flashes off in the pre-distiller 30 . The remaining oil flows to an FFA stripper 32 where the remaining FFA is stripped by injecting steam (box 110 , line 111 ) at various levels in the column (box 112 ). In this implementation, FFA-free, or refined oil is removed (box 114 ), and the steam strips the FFA and carries it with it as vapors into a fatty acid scrubber 40 where the FFA is condensed (box 116 ). In the scrubber 40 , cooled FFA is used to scrub the FFA from steam vapors. The liquid FFA is collected in the fatty acid collection tank 34 . The collected FFA is then pumped with a pump 36 through a cooler 38 back into the fatty acid scrubber 40 (shown at line 41 ). The vacuum system (box 118 ) is configured to achieve the desired pressure in the predistiller 30 and FFA stripper 32 as well as the scrubber 40 and fatty acid collection tank 34 . In various embodiments, the vacuum system can be steam driven, such as with boosters and ejectors, or electricity driven, such as by blowers and mechanical pumps. In various implementations, several distinct vacuum systems (boxes 106 and 118 ) can be used, while in other implementations a single vacuum system, 80 is used throughout the system.
The stream from the bottom of the stripper 32 is pumped with pump 42 . In various implementations, since the oil is at very high temperature, heat is recovered in economizers 22 , 23 , 24 , 26 to heat the incoming oil. The finished product is refined oil with less than 1% (preferably below 0.5%) FFA. The refined oil flows out of the economizer 22 (shown at line 43 ) and is cooled in cooler HE-708 44 and polished in the bag filter 46 before being sent to the refined oil storage tank 50 . The recovered fatty acids are again collected in the fatty acid collection tank 34 and pumped with an oil pump 55 back to the high fatty acid or feedstock storage tank 54 for feeding to the glycerin esterification in Step-1 with a pump 56 .
Step-2: Various implementations have a glycerin-esterification step (box 120 in FIG. 2 ) wherein the HFFA oil produced in Step-1 is next pumped with a pump 56 . in these implementations, the HFFA oil is pumped through a start-up heater 60 to a glyceroysis reactor 62 . The reaction temperature is between 160° C. to 300° C. (preferably between 200-260° C.) at a pressure of 10 mm to 150 mm Hg absolute (preferably between 30-75 mm). Glycerin (box 122 ) is pumped from a glycerin tank 66 into the reactor 62 with a dozing pump 64 . In certain implementations, the above reaction may be accomplished in multiple stage reactors in a continuous operation.
In the implementation of FIGS. 1 and 1A -D, the fatty-acid contained in HFFA oil reacts with glycerol and converts to oil. The byproduct of the reaction is water. This water is continuously removed from the reactor due to heat and vacuum (box 118 ). In these implementations, any glycerol that is vaporized and carried along with water is condensed in a first condenser 70 at a controlled temperature so only glycerin is condensed. The water vapors are allowed to pass on to another condenser 72 where the vapors are condensed. The water is collected in a condensate tank 52 and discharged with a pump 53 . The condensate tank 52 is connected to a vacuum system 80 . In various embodiments, the vacuum system can be steam driven, such as with boosters and ejectors, or electricity driven, such as by blowers and mechanical pumps. The finished product of the glycerolysis step is LFFA oil (box 124 ) and is transferred with a pump 82 to the FFA stripping step (Step 1, box 126 ) to completely remove FFA to less than about 1.0% or less than about 0.5%.
EXAMPLE 2
Oil Containing More than about 20% FFA
Step-1: As shown in FIGS. 1-1D and 3 at 10 and 200 , in certain implementations, the disclosed high free fatty acid (“HFFA”) process consists of a glycerin-esterification step wherein the HFFA containing oil (20-100% FFA, shown in FIG. 3 at box 210 ) is pumped from a high fatty acid tank 54 with a pump 56 . The HFFA oil (box 212 ) is pumped through a start-up heater 60 to a reactor 62 . The reaction temperature is between 160° C. to 300° C. (preferably between 200-260° C.) at a pressure of 10 mm to 150 mm Hg absolute (preferably between 30-75 mm Hg absolute).
Correspondingly, glycerin (box 122 ) is pumped from a glycerin tank 66 into the reactor 62 with a dozing pump 64 . The fatty-acid contained in HFFA oil reacts with glycerol and converts to oil (box 120 ). A byproduct of the reaction is water. The water is continuously removed from the reactor due to heat and vacuum. Any glycerol that is vaporized and carried along with water is condensed in a first condenser 70 at a controlled temperature so only glycerol is condensed. The water vapors are allowed to pass on to another condenser 72 where it is condensed. The water is collected in a condensate tank 52 and discharged with a pump 53 . The condensate tank 52 can also be connected to a vacuum system 80 . In various embodiments, the vacuum system can be steam driven, such as with boosters and ejectors, or electricity driven, such as by blowers and mechanical pumps. In various implementations, several distinct vacuum systems (boxes 106 and 118 ) can be used, while in other implementations a single vacuum system, 80 is used throughout the system.
The reaction presented above may be accomplished in multiple stage reactors in a continuous operation. The finished product is LFFA oil and is transferred with a pump 82 to the FFA stripping step (Step-2 below) to completely remove FFA to less than about 1.0% or less than about 0.5%, for example.
Step-2: The disclosed process further consists of an FFA stripping step wherein glycerin-esterified oil from Step-1 (box 126 ) is stripped of FFA. The LFFA oil is pumped with pump PU-701L 14 to a pre-distiller TK-704 30 , as previously described (boxes 104 - 116 ). In this implementation, the temperature is raised to between 180° C.-300° C. (preferably between 230-280° C.) at a pressure of 1-10 mm Hg absolute (preferably between 3-5 mm Hg absolute).
Again, the majority of the FFA flashes off in the pre-distiller 30 (box 108 ). The oil flows over to an FFA stripper 32 where the remaining FFA is stripped by injecting steam (box 110 ) at the various levels in the column. The steam strips FFA (box 112 ) and carries it with it into the fatty acid scrubber 40 where the FFA is condensed (box 116 ).
In various embodiments, cooled FFA is used to scrub the FFA from steam vapors. The liquid FFA is collected in the fatty acid collection tank 34 . The collected FFA is pumped with a pump 36 through a cooler 38 into the fatty acid scrubber 40 (shown at line 41 ). The stream from the bottom of the stripper 32 is pumped with a pump 42 . Since the oil is at very high temperature, heat is recovered in economizers 22 , 23 , 24 to heat the incoming oil. The finished product is refined oil with less than about 1.0% FFA, less than 1.0% FFA, or less than about 0.5% FFA. The refined oil (following line 43 ) is subsequently cooled in a cooler 44 and polished in the bag filter 46 before being sent to storage. The recovered fatty acids are collected in a collection tank 34 and pumped back to the feedstock storage tank 54 for feeding to the glycerin esterification in Step-1.
Although the disclosure has been described with reference to preferred embodiments, persons skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the disclosed apparatus, systems and methods.
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The disclosed apparatus, systems and methods relate to the conversion of high free fatty acid (“HFFA”) containing oils defined as oils containing 20-100% free fatty acids (“FFA”) and low free fatty acid (“LFFA”) containing oils defined as oils containing 1-20% free fatty acids (FFA) into oil with less than about 0.5-1% FFA. If the feedstock is HFFA oil, the process includes a combination of partial glycerolysis of HFFA oils to produce LFFA oils and subsequent stripping of LFFA oils to produce NFFA oils via steam distillation. If the feedstock is LFFA oil, the process includes stripping of LFFA oils to produce NFFA oils via steam distillation and subjecting FFA to partial glycerolysis to convert FFA to oil.
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BACKGROUND OF THE INVENTION
This invention relates to a process for cleaning soiled materials, the wastewaters from the process being chemically, mechanically and biologically treated and then returned to the process.
The industrial cleaning of soiled materials is normally carried out in washing machines using a detergent-containing aqueous liquor. After the actual washing process, the washed material is repeatedly rinsed with water and then dried and further processed. In this process, the disposal of the wastewater accumulating, which is polluted with detergent residues and other ingredients, represents a considerable cost factor. In the washing of feather or downs or in the washing of raw hide for leather manufacture, the wastewater is polluted, for example, with large amounts of emulsified fat. In the washing of dyed cotton fabrics, for example in mechanical stone-wash washing with pumice stones or in the washing of blue jeans, the wastewater contains dissolved and/or dispersed dyes and fiber residues.
In view of stricter anti-pollution legislation, the untreated wastewater is no longer allowed to leave the process so that treatment of the wastewater is unavoidable. The high consumption of freshwater for the treatment process, especially in countries and regions with limited water resources, is also a considerable cost factor.
Accordingly, there is a need for a cleaning process for soiled materials which would involve minimal water consumption and hence could be operated less expensively than known processes and which, at the same time, would lead to reduced environmental pollution by wastewater.
SUMMARY OF THE INVENTION
The present invention therefore relates to a washing process for soiled materials in which the material to be washed is contacted with an aqueous detergent-containing liquor and then rinsed at least once with water, the wastewater from the wash and rinse cycles is collected, chemically, mechanically and biologically treated and then returned to the washing process, characterized in that the treated wastewater is used both for the rinse cycle and, after addition of the detergent, for the wash cycle.
The process according to the invention is particularly suitable for washing fat-soiled material, the wastewater being treated by
A) complete or partial treatment in a fat separator after addition of a demulsifier and then
B) mechanical prepurification by flotation and/or sedimentation before the biological treatment step.
In the context of the invention, fat-soiled material is understood to be material which contains 0.3 to 16% by weight of fat, based on the weight of the material. The term “fat” in the context of the invention encompasses natural or synthetic glycerol esters of higher fatty acids as described, for example, in Römpps Chemie Lexikon, Vol. 2, pages 1339-1342, 1990. The process according to the invention is particularly suitable for cleaning feathers or downs. Besides fat, feathers and downs contain skin particles, blood, droppings, vegetable impurities and large quantities of dust. Fat-soiled material in the sense of the present invention also occurs in the washing of leather, especially raw hides.
However, the process according to the invention is also suitable for washing dye-soiled material, i.e. in the context of the invention material which releases dyes into the wastewater during washing. In this case, the wastewater is treated by complete or partial chemical and mechanical prepurification by
a) reaction with a suitable oxidizing agent and then
b) flotation and/or sedimentation before the biological treatment step.
Materials which release dyes into the wastewater include, for example, freshly dyed cotton fabrics or other textiles where excess dye is to be removed by washing as, for example, in mechanical stone-wash washing with pumice stones or in the washing of blue jeans.
The soiled material is washed in a suitable washing machine, for example a cylinder washing machine or a washer-extractor. Washing is normally carried out at temperatures of 5° C. to 60° C. However, feathers are preferably washed with cold water at temperatures of 20° C. to 30° C. while blue jeans are normally washed at up 60° C.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
FIG. 1 is a flow chart showing the steps of the claimed process.
DETAILED DESCRIPTION OF THE INVENTION
Detergents suitable for cleaning the material include any of the biodegradable types known to the expert for this purpose. These detergents normally contain anionic, cationic and/or nonionic surfactants. It is of particular advantage to use detergents based on nonionic surfactants, for example C 7-15 fatty alcohols which have been reacted with 3 to 10 mol of ethylene and/or propylene oxide per mol of fatty alcohol. Other suitable detergent ingredients are diethylene glycol ethers, more particularly diethylene glycol monobutyl ether, and reaction products of ethylene and/or propylene oxide with fatty acids. Reaction products of C 10-20 fatty acids with 8 to 12 mol of ethylene oxide per molecule of fatty acid are particularly suitable.
The quantity of detergent used depends mainly on the degree of soiling of the material. The detergent is preferably used in quantities of 0.1 to 5% by weight, based on the weight of the material to be washed. In addition, the process according to the invention is designed in such a way that the quantity ratio of material to water is preferably between 1:5 and 1:15. Besides the detergents described above, other substances may be used in the process according to the invention in the washing and rinsing steps, including for example antistatic agents, odor inhibitors, bleaching agents, water softeners, blueing agents and bacteriostatic agents. These auxiliaries are added to the wash or rinse liquor in the quantities known to the expert, normally between 0.1 and 3% by weight, based on the weight of the material to be washed.
The process according to the invention is distinguished by the fact that the water used in the washing and rinsing steps contains treated wastewater which has been returned to the process. The consumption of freshwater and hence the washing costs are thus reduced. The water used in the process preferably contains up to 80% by weight of treated wastewater. However, the process may also be designed with advantage in such a way that the proportion of freshwater that has to be added to the circuit can be reduced to 10% by weight. The wastewater can thus be almost completely recovered. The water losses are mainly attributable to evaporation and to the removal of water in the moisture of the washed material after undergoing the washing process.
After the washing step, the washing water is pumped off and the material is rinsed with water. Detergent residues and fat or dyes and optionally solids adhering to the washed material are rinsed off in the rinsing step until the rinsing water is clear. This may be done in the washing machine itself or in a separate rinsing unit. The rinsing steps are preferably carried out in the washing machine.
The quantity ratio of washed material to rinsing water is preferably between 1:5 and 1:40 per rinse cycle. The washed material is rinsed with water at least once but preferably several times, more particularly between 3 and 6 times.
The washing process according to the invention is advantageously designed in such a way that between 3 and 6 cubic meters of water are required for the complete washing of 100 kg of material, i.e. for the washing and rinsing steps.
The wastewaters from the rinse cycles are also collected, combined with the wastewater of the washing step, chemically, mechanically and then biologically treated and returned to the process. To this end, the wastewaters from the washing and rinsing steps are first completely or partly prepurified both chemically and mechanically.
In the case of fat-containing soils, a suitable chemical which breaks up the fat/water emulsion is first added to the wastewater. Iron salts, such as FeCl 3 , are preferably used as demulsifiers, although AlCl 3 or mixtures with iron salts may also be used. The demulsifier is used in quantities of preferably 1 to 10 g/m 3 wastewater and more preferably 2 to 5 g/m 3 wastewater.
The chemically treated wastewater is then introduced into a fat separator. Any units and equipment known to the expert may be used for this purpose. The fat globules separated off float on the surface of the water and are mechanically removed.
The wastewater thus prepurified is then freed from any solids present by flotation and/or sedimentation. It is preferably subjected both to sedimentation to remove coarse solids and to flotation to remove fine-particle soil, for example feather dust. This step may also be carried out in flotation or sedimentation units known to the expert.
If materials which release dyes to the wastewater are washed, the chemical treatment is carried out by first adding to the wastewater a suitable oxidizing agent which reacts with the dyes dissolved or dispersed in the water. Ozone is preferably used as this oxidizing agent in the process according to the invention.
The chemically and mechanically pretreated wastewater is then transferred to a biological treatment stage in which the wastewater is free from the surfactant residues. The biological treatment stage normally consists of a fixed-bed reactor and activated sludge. A degradation of more than 95% by weight of the surfactants is normally achieved in such treatment units. The treated wastewater is then introduced into a secondary sedimentation tank to separate the sludge from the water. The sludge accumulating there is dewatered and may then be put to use, for example as an agricultural fertilizer.
The wastewater thus treated may now be reused for the wash and rinse cycles. However, it has proved to be of advantage further to treat the wastewater—after the biological stage—in an aftertreatment step carried out by flocculation in the presence of a flocculation aid. Bacterial mass or activated sludge discharged from the biological treatment stage is removed by this aftertreatment. The flocculation agent used in this aftertreatment may be selected from any of the compounds known to the expert for this purpose, anionically modified polyacrylamides preferably being used. To this end, the flocculating agent is used in quantities of 0.1 to 2 g/m 3 wastewater and preferably in quantities of 0.5 to 1 g/m 3 wastewater. However, it can also be of advantage to filter the wastewater following the aftertreatment before it is returned to the wash and rinse cycles. This filtered water is particularly suitable for the final rinse cycle of the process.
In a particularly preferred embodiment of the process according to the invention, only the wastewater of the wash cycle and the first rinse cycle is chemically pretrated and the used water of the other rinse cycles is collected in an equalization tank. The chemically pretreated wastewater is combined with the water from the equalization tank and the combined wastewaters are then further prepurified by flotation and/or sedimentation and subsequently delivered to the biological treatment stage.
It can also be of advantage to design the process in such a way that the wastewater of the washing step is treated and the wastewater thus treated is used in countercurrent in the rinsing units. The wastewater from the rinsing units is then used for washing after addition of the detergents and other auxiliaries required and subsequently resubjected to the treatment process.
The process according to the invention enables soiled materials to be inexpensively washed. The materials are generally washed in batches. The wastewater accumulating is treated, being circulated—preferably continuously—to this end. However, to ensure that the biological treatment stage retains its cleaning effect, nutrient-containing water has to be continuously passed through this treatment stage. Accordingly, the problem arises of designing the process in such a way that, even where the level of pollution by waste matter is low and in non-operational periods, the biological treatment stage retains its cleaning effect because the bacterial lawn and/or the activated sludge would soon lose activity without sufficient nutrients from the wastewater. Accordingly, it has proved to be of advantage to design the process in these periods in such a way that the water is circulated between the equalization tank and the biological treatment stage. In order to retain the activity of the bacterial lawn or the bacterial flocs, a suitable food for bacteria is added in sufficient quantities to the water. This food provides the bacteria with the missing nutrients, particularly nitrogen and phosphorus.
EXAMPLE
The washing of feathers is described in the following as an example of the washing process according to the invention.
FIG. 1 is a flow chart of the process.
The following quantities of water were used to wash 100 kg of feathers:
1000 l of water in the washing step
1000 l of water in the 1st rinse
500 l of water in the 2nd rinse
500 l of water in the 3rd rinse
500 l of water in the 4th rinse
1000 l of water in the 5th rinse.
The wash and rinse cycles were carried out in a washing machine. The ratio of washing water to feathers was 1:10. The feathers were soiled with solids (feather dust etc.) and about 6.5% fat. About 0.5 to 1% fat remained on the feathers after washing so that ca. 5.5 to 6.0 g of fat entered 1 l of wash liquor. If the fat is assumed to be based on stearic acid, 1 g of fat corresponds to ca. 750 mg org. C and 6 g of fat to ca. 4500 mg org. C. The wash liquor contained 3 kg of detergent and 0.5 kg of auxiliaries per 100 kg of feathers. The detergent contained 70% of organic material of which about two thirds are org. C: accordingly, 3 g of detergent contain 1400 mg org. C. The auxiliary contains 50% organic material of which about two thirds are org. C; accordingly, 0.5 g of auxiliary contains 200 mg org. C.
1 l of wash liquor contains 4500 mg org. C from fat, 1400 mg of org. C from the detergent and 200 mg org. C from the auxiliary, making a total of 6100 mg org. C.
<3 g/l fat, <1 g/l detergent ingredients, ≦0.2 g/l auxiliary ingredients and various quantities of solids were removed from the wash liquor and rinsing water of rinse 1. They were introduced into the fat separator after demulsification with a demulsifier based on metal salt (Microfloc EFW, a product of Henkel KGaA). After fat separation, the wastewater still contained <1 mg/l fat. The other water ingredients were 20-30% removed, leaving 800 mg/l detergents ingredients, 150 mg/l auxiliary ingredients and various quantities of solids.
The following maximum quantities of org. C remained in 1 l pretreated wastewater: 0.7 mg from fat, 500 mg from detergent and 100 mg from auxiliary, making a total of 600 mg.
The pretreated wastewater (from the wash cycle and rinse 1) and the wastewater of the other rinses were combined in an equalization tank and then subjected to flotation/sedimentation. The combination of the two wastewaters changed the contents of the wastewater as follows:
Substance [mg/l]
Org. C [mg/l]
Fat
0.5
0.3
Detergent
350
225
Auxiliary
70
45
Total
270
The wastewater with these ingredients was freed from the solids in the flotation/sedimentation stage. This wastewater was introduced into an immersion-type bacteria bed reactor for biological treatment. This reactor consists of a fixed-bed reactor (wheels with upgrowth) and activated sludge. Given a holding time of about 12 h, the biological degradation can assumed to be >>95%.
After the biological treatment, the following C contents were obtained per liter of wastewater: 0.3 mg from fat, 45 mg from detergent and 9 mg from auxiliary, making a total of <55 mg.
The treated wastewater from the activated-sludge stage was introduced into a secondary sedimentation tank to separate the sludge from the water. Flocculation/precipitation in the presence of a flocculant based on an anionically modified polyacrylamide was then carried out for further purification. The water thus reconditioned was directly used for the wash cycle and for rinses 1 to 4. The remaining water was filtered for further purification and desalting. It was then used for the 5th rinse cycle. The water loss occurring was made up with freshwater (ca. 10%) in the 5th rinse.
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A process for washing fat- or dye-soiled materials involving: (a) providing a fat- or dye-soiled material; (b) providing an aqueous detergent-containing liquor; (c) contacting the fat- or dye-soiled material with the aqueous detergent-containing liquor, thus forming a washed material and wash wastewater; (d) providing a source of rinse water; (e) rinsing the washed material with the rinse water, at least once, thus forming rinsed material and rinse wastewater; (f) collecting both the wash and rinse wastewater; (g) chemically pretreating the collected wash and rinse wastewater by contacting it with a compound selected from the group consisting of a demulsifier, an oxidizing agent and mixtures thereof to form waste particles; (h) mechanically removing the waste particles from the collected wash and rinse wastewater by flotation or sedimentation to form prepurified wash and rinse wastewaters; (i) biologically treating the prepurified wash and rinse wastewater by introducing it into a fixed-bed reactor containing activated sludge to form a mixture of treated wastewater and sludge; (j) separating the treated wastewater from the sludge; and (k) recirculating the treated wastewater back into the aqueous detergent-containing liquor, the rinse water, or both.
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BACKGROUND
[0001] 1. Field of Invention
[0002] The present invention relates generally to a method and apparatus for shaping, storing, transporting and displaying athletic headwear. More particularly, the present invention relates to a method and apparatus for causing and maintaining a definite arch shape in the visor portion of a sports cap while the cap is being stored, transported or displayed. In addition, the lightweight, arched device allows for modular storage, easy transportation and enhanced display of the athletic headwear.
[0003] 2. Description
[0004] Various methods for curving the visor of headwear have been used for some time. Headwear—in particular sport team memorabilia such as ball caps—is fashionable, practical and comfortable. The most common type of headwear includes sports caps which have visors attached to help block out the sun and which are usually constructed of fabric covered cardboard or plastic. The purpose of a visor is to fashionably protect the face of the wearer from the environment, including rain, wind, and sun by providing a lateral appendage which extends from the head of the wearer. Because a flat visor is not as effective at blocking the rain, wind and sun and because an arched visor is more comfortable and considered more aesthetically pleasing, a visor is most effective if curved. However, most headwear manufacturers produce a flat visor.
[0005] The visor is usually constructed of a rigid material to help provide support to allow the visor to extend outward from the face and keep the visor from succumbing to the rain and wind. Because the material which forms the visor is rigid, it is not easy to maintain an arch in the visor. In fact, the current methods for curving the visor are problematic.
[0006] One method for curving the visor involves manually rolling the visor according to the wearer's preference. Other manual methods include using rubber bands of various types and sizes to curve the visor. Not only do these methods create an inconsistent arch and cause an early break-down of the visor materials due to the repeated physical stress of the materials, but also these methods fail over time and the visor loses its arch shape within a relatively short timeframe.
[0007] Another method of curving the visor involves using an apparatus to create tension on the visor either from compression, steam, hot air or moisture to impose an arch in the rigid visor material. These machines are costly, burdensome, bulky and difficult to use. Because of the stress imposed on the visor, visor breakdown is accelerated.
[0008] A third method currently used is to curve headwear during use. However, these devices change the nature of the headwear, increasing the weight of the headwear, changing the aesthetics and altering the mass distribution, ultimately causing the visor to wear lower on the head. In addition, because of the nature of the curving device, which remains on the headwear during use, over time a permanent discoloration of the visor will occur.
[0009] Another challenge is transporting headwear while retaining the curved arch. When packing headwear to travel, the visor is often smashed between multiple layers, causing the visor to lose any arch in the visor. Current methods involve bulky machinery or multiple components, which can be lost or damaged and thereby do not lend themselves to traveling.
[0010] Another known problem is that while traveling, in an effort to store the headwear inside the luggage, the headwear is often crushed or reshaped when other items are packed on top of the headwear or during the transportation of the luggage.
[0011] There is a need for a visor curving device which is compact, lightweight, easy to use, with a fixed arcuate channel for curving the visor during non use, providing a professional and aesthetic display during storage and transportation, while requiring a reduced material composition and therefore a more economical use of material and space.
[0012] Information relevant to attempt to address these problems can be found in U.S. Pat. Nos. 5,553,652; 5,685,465; 5,908,146; 5,991,927; 6,315,175; and published U.S. Patent Application Ser. Nos. 2003/0019890; 2003/0226861; and 2003/0217405. However, each one of these references suffers from one or more of the following disadvantages: unequal distribution of pressure, aesthetically distracting, inconsistent curve, overly complex, non-modular design, massive and non-economic use of material and space.
[0013] For the foregoing reasons, there is a need for a device which solves these problems by providing a cost effective, compact, lightweight device with a fixed arch for curving a visor.
SUMMARY OF THE INVENTION
[0014] The advantages of the present device include the simplicity, ease of use, light weight, reduced material consumption and compactness, all of which provide an improved method for shaping athletic headwear.
[0015] In addition, the present invention provides a unique display method which allows graphical images to be affixed along the arch or on the stabilizing arm of the shaping device. The present invention also provides a unique modular storage method by allowing the stacking of a plurality of headwear on top of one another positioning the bottom portion of one shaping device on top of the visor portion of another.
[0016] The current invention also solves the problem of transporting athletic headwear by allowing the user to place the visor portion of the headwear inside the curving device and then pack the headwear. The curving device will pack easily, maintain the visor's arch and is lightweight. In addition, because the headwear curvature device is comprised of a single compact unitary device, it will not get lost or tangled during transportation and will not take up a large space within the luggage.
[0017] It is an object of the current invention to provide an improved device, which modifies the visor portion of headwear by providing a simpler, easier to use, lightweight, compact and cost efficient shaping device which improves the method for shaping, storing, transporting and displaying athletic headwear.
[0018] It is a specific object of the invention to provide such a device which is comprised of an arch shaped structure attached to and supported by a stabilizing support member. The arch structure has an opening defined by a first terminal end and a second terminal end spaced apart a sufficient distance to allow the opening to receive the visor portion of headwear. The opening bisects the arch structure into an upper arcuate portion and a lower arcuate portion such that the upper and lower arcuate portions cause uniform pressure along the perimeter of the visor shaping the visor into the fixed arch shape. In addition, the invention provides an improved method for displaying, transporting, shaping and storing the athletic headwear.
[0019] In accordance with one aspect of the present invention, the shaping device is comprised of a unitary shaped body which includes an arch structure connected to and supported by a stabilizing arm. The arch structure provides a channel to receive the visor portion of athletic headwear.
[0020] In accordance with a second aspect of the invention, the invention provides an improved method for displaying the headwear such that a graphical image is affixed along the front face of the shaping device.
[0021] In accordance with a third aspect of the invention, the invention provides an improved method for storage of the headwear such that the shaping device provides support and spacing for the headwear while being stored.
[0022] In accordance with a fourth aspect of the invention, the invention provides an improved method for transporting the headwear such that the lightweight and compact shaping device maintains the shape of the headwear during transportation.
[0023] These, and further features and advantages of the invention, may be better understood with reference to the accompanying specification and drawings which illustrate by way of example, the principles of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] The accompanying drawings illustrate the present invention. In such drawings:
[0025] FIG. 1 depicts the front view of the improved shaping device in which the visor portion of the headwear is inserted inside the arcuate shaped channel of the shaping device.
[0026] FIG. 2 depicts a front profile view of the improved shaping device in which the arcuate shaped channel is in receipt of the headwear's visor.
[0027] FIG. 3 depicts a front profile of a plurality of headwear positioned such that the visor filled shaping devices are positioned vertically on top of each other.
[0028] FIG. 4 depicts the front face of the current invention.
[0029] FIG. 5 depicts a side profile of the current invention.
[0030] FIG. 6 depicts a profile view of the current invention rotated along the vertical axis.
[0031] FIG. 7 depicts the front plan view of the preferred embodiment of the current invention.
[0032] FIG. 8 depicts the front plan view of an alternative embodiment of the current invention.
DETAILED DESCRIPTION OF THE INVENTION
[0033] These, and further features of the invention, an improved athletic headwear shaping device, may be better understood with reference to the accompanying specification and drawings depicting the preferred embodiment, in which: FIG. 1 depicts a front view of the improved shaping device ( 10 ) and athletic headwear ( 20 ) in which the visor ( 21 ) is positioned in the channel ( 12 ) of the device. The improved shaping device ( 10 ) is an arcuate unibody device which is generally semi-circular. The shaping device is separated by an arcuate channel ( 12 ) into an upper arcuate region ( 13 ) and a lower arcuate region ( 14 ). The channel ( 12 ) has a first terminal end ( 15 ) and a second terminal end ( 16 ) which are connected to the first support stabilizing arm ( 17 ) and the second support stabilizing arm ( 18 ).
[0034] The shaping device ( 10 ) is designed to receive a visor ( 21 ) of standard width ( 22 ) and thickness ( 23 ). The molded visor will generally be semi-circular defined by a height (H) above a horizontal plane and an accurate width (W) bisected by the vertical axis of the headwear.
[0035] As shown in FIG. 1 the headwear's visor ( 21 ) fits into the shaping device ( 10 ) such that the upper arcuate region ( 13 ) and the lower arcuate region ( 14 ) distribute complementary forces along the perimeter of the visor ( 21 ) while positioned inside the channel ( 12 ). In FIG. 1 , the visor ( 21 ) of the headwear ( 20 ) is molded by distributing a downward force along the outer perimeter of visor ( 21 ) which is in contact with the upper arcuate region ( 13 ) and by distributing an upward force along the inner perimeter of visor ( 21 ) which is in contact with the lower arcuate region ( 14 ). The upper arcuate region ( 13 ) forces the visor ( 21 ) against the lower arcuate region ( 14 ). Conversely, the lower arcuate region ( 14 ) forces the visor ( 21 ) against the upper arcuate region ( 13 ). These complementary forces mold the visor ( 21 ) into an arcuate shape.
[0036] FIG. 2 . depicts a front perspective view of the improved shaping device in which the visor ( 21 ) is inserted a distance (D) from the edge of the visor ( 24 ) through the channel ( 12 ) of the shaping device ( 10 ). As seen in FIG. 2 the first and second terminal ends ( 15 & 16 ) are connected to a first stabilizing support arm ( 17 ) and a second stabilizing support arm ( 18 ).
[0037] In the preferred configuration the stabilizing support arms ( 17 & 18 ) are perpendicular to the visor ( 21 ) and at least one stabilizing support arm ( 17 ) is elongated outward to prevent rotation of the headwear. In addition, the preferred elongated support arm ( 17 ) has an elongated shape ( 19 ) which facilitates the placement of a graphical image onto the shaping device in close proximity to the shaped visor ( 21 ). The first and second support stabilizing arms ( 17 & 18 ) are preferably flat on their base, parallel to one another and fabricated from the same rigid material as the shaping device ( 10 ).
[0038] FIG. 2 also depicts the elevation and support of the visor ( 21 ) by the shaping device ( 10 ). Insertion of the visor ( 21 ) into the channel ( 12 ) of the shaping device ( 10 ) a distance (D) from an external edge of the visor ( 24 ) elevates the visor a height (H) above the horizontal plane.
[0039] The elevation of the visor ( 21 ) defines the molded shape and enhances the display characteristics of the headwear ( 20 ). This configuration also enhances the display of the headwear by allowing graphical images to be affixed along both the upper ( 13 ) and lower ( 14 ) arcuate portions of the device. In addition to the arcuate portions, the supporting structures ( 17 & 18 ) can display graphical images. By improving material efficiency, by elevating the visor above the horizontal plane and by displaying graphical images in multiple locations on the shaping device ( 10 ), the invention is an improvement over earlier inventions.
[0040] FIG. 3 depicts a plurality of headwear ( 20 ) and headwear devices ( 10 ) stacked vertically. The headwear can also be positioned side-by-side laterally from one another along a horizontal plane. In the preferred vertical arrangement the second headwear ( 40 ) is stacked on top of the first headwear ( 20 ). The first headwear visor ( 21 ) is inserted into the first shaping device ( 10 ). The second headwear visor ( 41 ) is inserted into the second shaping device ( 30 ). The lower arcuate portion ( 34 ) of the second shaping device ( 30 ) rests on top of the visor portion ( 21 ) of the first headwear ( 20 ) which is supported by the stabilizing support arms ( 17 & 18 ).
[0041] This improved, modular, compact, space saving design can accommodate a variable number of headwear ( 20 ) stacked vertically while molding the headwear visor ( 21 ) and provide for the display of a graphical image along the upper and lower arcuate portion ( 13 & 14 ) or on the stabilizing support arms ( 17 & 18 ).
[0042] FIG. 4 depicts the front plan view of the unibody shaping device, preferably constructed of a firm material such as metal or rigid plastic having an arched shape with a generally semi-circular cross section. The arcuate channel ( 12 ) which separates the unibody device. Said channel ( 12 ) having an upper edge, a lower edge, said upper edge separated from the lower edge by a width (W) that is greater than or equal to standard thickness ( 23 ) of the visor ( 21 ) and an arch length (P) that is equal to or greater than a lateral width ( 22 ) of the visor ( 21 ). In the preferred embodiment, P is approximately four inches in circumference and W is approximately one-quarter (¼) of an inch. The channel ( 12 ) has a first terminal end ( 15 ) a second terminal end ( 16 ) which define the perimeter of the channel and allow for positioning of the visor ( 21 ). In the preferred embodiment the first terminal end ( 15 ) and a second terminal end ( 16 ) are each integrated into the support stabilizing arms ( 17 & 18 ) of the shaping device. The shaping device ( 10 ) is preferably comprised of a single piece of rigid ABS plastic with an opening for the arcuate shaped channel ( 12 ) which extends through the interior of the device ( 10 ).
[0043] The portion of the shaping device ( 10 ) external to the arcuate channel ( 12 ) is referred to as the upper arcuate portion ( 13 ). The portion of the shaping device ( 10 ) internal to the arcuate channel ( 12 ) is referred to as the lower arcuate portion ( 14 ). In the preferred embodiment, one support stabilizing arm ( 17 ) is configured to prevent the athletic headwear from rotational movement along the longitudinal axis by elongating the stabilizing arm outward. In the preferred embodiment, this elongated support stabilizing arm ( 17 ) is of sufficient design ( 19 ) to allow a graphical image to be affixed near the first terminal end ( 15 ) and adjacent to the channel opening ( 12 ).
[0044] FIG. 5 depicts the side plan view which shows the improved shaping device ( 10 ) with a device thickness (d) which separated the front surface from the back surface. In the preferred embodiment the shaping device thickness (d) is one-eighth (⅛) inches thick. By minimizing the device thickness (d), the invention has an improved material efficiency over the current shaping devices. However, this thickness is optimized to provide sufficient support to mold and support the visor ( 21 ) during the invention's use.
[0045] FIG. 6 depicts the invention rotated around the vertical axis.
[0046] FIG. 7 depicts the preferred embodiment of the invention in which the support stabilizing arm ( 17 ) is elongated and preferably shaped ( 19 ) to display a one-half (½) inch graphical image adjacent to the arcuate channel ( 12 ).
[0047] FIG. 8 depicts an alternative embodiment of the invention in which the shaping device ( 10 ) is fabricated of a perforated material, further improving material efficiency.
[0048] The invention further includes a method for shaping the visor ( 21 ). The method comprises a plurality of steps. First, providing an article of headwear ( 10 ) having a visor ( 21 ) and providing an improved shaping device ( 20 ). The improved shaping device ( 20 ) has a channel ( 12 ) of width P sufficient to receive a standard width visor ( 21 ) and first and second support stabilizing arms ( 17 & 18 ). The visor ( 21 ) is inserted into the channel ( 12 ) such that the upper arcuate region ( 13 ) and lower arcuate region ( 14 ) forcibly hold the visor inside the channel ( 12 ). By forcibly holding the visor ( 21 ) inside the arcuate shaped channel ( 12 ), the improved shaping device imparts the desired shape on the visor ( 21 ).
[0049] The invention further includes a method for displaying the visor ( 21 ). The method comprises a plurality of steps. First, providing an article of headwear ( 10 ) having a visor ( 21 ) and providing an improved shaping device ( 20 ). The improved shaping device ( 20 ) has a channel ( 12 ) of width P sufficient to receive a standard width visor ( 21 ), upper and lower arcuate regions ( 13 & 14 ), first and second support stabilizing arms ( 17 & 18 ) and graphical images affixed to stabilizing arms. The visor ( 21 ) is inserted into the channel ( 12 ) such that the upper arcuate region ( 13 ) and lower arcuate region ( 14 ) forcibly hold the visor inside the channel ( 12 ). By forcibly holding the visor ( 21 ) inside the arcuate shaped channel ( 12 ), the improved shaping device forces the visor to extend horizontally, allowing for an improved graphical display alongside the visor ( 21 ).
[0050] The invention further includes a method for storing the visor ( 21 ). The method comprises a plurality of steps. First, providing a plurality of articles of headwear ( 10 ) having a visor ( 21 ) and providing a plurality of improved shaping devices ( 20 ). Each improved shaping device ( 20 ) has a channel ( 12 ) of width P sufficient to receive a standard width visor ( 21 ) upper and lower arcuate regions ( 13 & 14 ), and first and second support stabilizing arms ( 17 & 18 ). Each visor ( 21 ) is inserted into the channel of each shaping device ( 12 ) such that the upper arcuate region ( 13 ) and lower arcuate region ( 14 ) forcibly hold the visor inside the channel ( 12 ). Each successive headwear shaping device-combinations is vertically placed on top of one another such that each lower arcuate region ( 14 ) rests on the visor ( 21 ) of the previous item of headwear ( 10 ). By vertically stacking the headwear, an improved storage method is obtained. Although the present invention has been described in considerable detail with reference to certain features or preferred versions thereof, other versions are possible and the invention does not require the incorporation of all advantageous features into every embodiment of the invention. For example, multiple channels or multiple configurations for receiving a visor ( 21 ) or alternative stabilizing support arms ( 17 & 18 ) can be configured which support the arcuate shaping device ( 20 ). Therefore, the spirit and scope of the appended claims should not be limited to the description of the preferred versions contained herein.
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An improved headwear shaping device which is compact, lightweight, modular and contains an arcuate channel for receiving the visor portion of athletic headwear, shaping the visor by applying equal pressure throughout the perimeter of the visor. The shaping device also provides a stabilizing arm perpendicular to the inserted visor causing the visor to extend parallel to the horizontally axis of the cap for display and storage. The unitary shaped body of the invention is comprised of a lightweight, compact, cost-effective rigid material which also provides for enhanced portability of headwear while not in use.
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CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation of U.S. patent application Ser. No. 09 / 458 , 337 , filed on Dec. 10, 1999 which U.S. patent application Ser. No. 09/458,337 claims benefit of U.S. Provisional Patent Application Serial No. 60/126,836 filed Mar. 30, 1999.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The invention relates to electronic data storage and access. More particularly, the invention relates to a method and apparatus for storing and retrieving multiple electronic data streams having different bit rates.
[0004] 2. Description of the Background Art
[0005] Multimedia systems store and retrieve video, audio and other content from mass storage devices, e.g., disk drive arrays. One such system provides video-on-demand (VOD) to an end user. Such a VOD system stores video content in memory and retrieves the content upon demand. The VOD system then serves the video content to the end user requesting the video content.
[0006] The VOD system uses a VOD server for storing and accessing video content or a plurality of video files. The VOD server processes the video content as data packets and stores the video content into extents or logical memory blocks within a memory. The data packets generally comply with one or more of the Moving Pictures Experts Group (MPEG) standards. To store these data packets in a redundant manner, the VOD server may stripe the video content over an array of disks within the memory. Each video file may occupy several physical disk blocks or disk tracks within the disk drives.
[0007] Multimedia programs are encoded using various resolutions of encoding depending upon the content of the program, i.e., sporting events are encoded with higher resolution than situation comedies. The bit rate of high-resolution encoded program is greater than a bit rate of a low-resolution encoded program. As such, for a given unit of program time, a high resolution encoded program generates more packets than are generated when forming a low resolution encoded program. Consequently, a video server must be able to store a plurality of programs having constant bit rates. To facilitate storage of multiple constant bit rate programs, current servers require the bit rates of various programs to be integer multiple of one another such that the extents of any given program are of equal size and the extents across programs are integer multiples of each other. Such a restrictive storage system is not flexible in providing storage of any form of programming, i.e., programs having non-integer bit rates. Consequently, current video servers do not store programming in an optimal manner.
[0008] Therefore, there is a need in the art for an improved method and apparatus for storing an accessing multiple constant bit rate video programs wherein the bit rate of programming can be arbitrary.
SUMMARY OF THE INVENTION
[0009] The invention overcomes the disadvantages associated with the prior art by a method and apparatus for defining constant time length (CTL) extents to store packetized video streams having multiple constant bit rates (MCBR), i.e., each stream has a constant bit rate within the stream, but different as compared to other streams. Specifically, the method analyses the bit rate of a given stream and determines an appropriate length for a CTL extent within which to store data packets that comprise the stream. The extent is a number of bits that can be read from memory during a data read period for a given bit rate, rounded up to the next full packet. The method then stores the extents and pads some extents with a null packet, as needed, to compensate for accumulated partial packets of data. The null packets are referred to as dither null packets to differentiate them from the null packets that appear in a standard encoded video bitstream. Consequently, any bit rate stream can be stored in this manner with a minimum utilization of dither null packets. The extents are stored by striping them onto a disk array, i.e., one extent per disk drive, then wrapping from the last drive in the array to the first. The method repeats for each data stream such that a plurality of constant bit rate streams are stored.
[0010] To read the data from the array, the extents are recalled one at a time and temporarily stored in a buffer memory. A data pointer is used to access the packets from the buffer. The dither null packets are skipped such that the output stream of packets does not contain dither null packets. The packets are coupled to a multiplexer. The multiplexer combines the packets into a transport stream to deliver the packets of video data to a downstream user.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The teachings of the present invention can be readily understood by considering the following detailed description in conjunction with the accompanying drawings, in which:
[0012] [0012]FIG. 1 shows a high level block diagram of a system for storing and retrieving data;
[0013] [0013]FIG. 2 shows process for storing MCBR data streams;
[0014] [0014]FIG. 3 shows a flow diagram of a routine for storing multiple constant bit rate (MCBR) data streams into memory.
[0015] To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures.
DETAILED DESCRIPTION
[0016] [0016]FIG. 1 depicts a high level block diagram of a video server system 100 for storing and retrieving data. The system 100 of FIG. 1 finds great utility in, e.g., a video of demand (VOD) system, as described in U.S. patent application Ser. No. 08/984,710, filed Dec. 3, 1997 and incorporated herein by reference. The system 100 comprises a server 102 and an array of storage disks 104 1 , 104 2 . . . 104 n , where n is an integer equal to the number of storage disks in an array used to store and retrieve data. The server 102 comprises an access controller 108 , a data buffer 110 , and a multiplexer (MUX) 112 . Other components and features of the system 100 not essential to the invention are not discussed herein.
[0017] In operation of the system 100 , the server 102 receives a data stream or video file from a video source 106 via signal path S 1 . The data stream is typically video content, such as a movie or live broadcast, in the form of an encoded and/or compressed bitstream using, illustratively, the MPEG-2 standard. The data stream is generally a sequence of data packets. The packets may be standard MPEG packets or they may be special transport packets such as those described in U.S. patent application Ser. No. 09/458,339, filed Dec. 10, 1999, (Attorney Docket 051) and is incorporated herein by reference.
[0018] The packets are organized into groups to facilitate storage. The groups of packets are known as extents. The video source 106 generally provides a plurality of constant bit rate video programs, i.e., MPEG bitstreams, having arbitrary bit rates. Each program may have a different bit rate as compared to other programs such that programs of various video resolution are made available to a viewer. Thus, for a given length of programming time, more or less packets represent each program depending upon the encoding parameters used to produce the encoded program.
[0019] The server 102 stores the data stream in a memory comprising an array of disks 104 1 , 104 2 . . . 104 n or some storage medium. The array of disks 104 1 , 104 2 . . . 104 n may be arranged in a Redundant Array of Independent Disks (RAID) configuration as discussed in The RAIDbook: A Source Book for Disk Array Technology, Fourth Edition (1995). Each disk 104 1 , 104 2 . . . 104 n in the array stores data as extents.
[0020] The server 102 stripes the data into array of disks 104 1 , 104 2 . . . 104 n illustratively in the manner shown in U.S. U.S. Pat. No. 5,920,702, issued Jul. 6, 1999 and incorporated herein by reference. The size of the extent is a constant time length (CTL) extent, where the extent represents a fixed period of programming time, i.e., a fixed number of encoded video frames. Each extent may store a plurality of data packets that represent video content and a null packet, as needed. The use of null packets shall be described below.
[0021] When a user requests to view a particular video or data stream, the video session manager (not shown) of the system 100 sends a control or enable signal to the server 102 . In response to this signal, the access controller 108 of the server 102 retrieves the extents for the requested program from the array of disks 104 1 , 104 2 . . . 104 n . The server 102 then buffers the retrieved program in buffer 110 and, using MUX 112 , combines the packets of the retrieved program with those of other programs to form a transport stream on signal path S 2 . The transport stream is coupled to a network and sent downstream to a user set top terminal for viewing.
[0022] [0022]FIG. 2 diagrammatically depicts the process used to store multimedia programming on the disk array 104 of FIG. 1. For simplicity two encoded movies 200 and 202 are shown having bit rates b 1 and b 2 , where b 2 is greater than b 1 and both bit rates are arbitrary.
[0023] The process first computes an extent size for each movie. The extent size in equal to the bit rate of the movie times the service interval over which the extent will be read from the disk drive. For example, if the bit rate for movie 1 (M 1 ) is 5 Mbps and the service period is 1.8 seconds, then the extent size will be 5984.04 packets (assuming 188 byte MPEG packets are used to carry the data). Since partial packets can not be stored, i.e., cannot be divided over two extents, the process rounds up to the next full packet. Additionally, rounding up ensures that a data underflow condition will not occur at the decoder, i.e., more data is being supplied per service interval than is necessary. As such, in this example, the extent size is 5985 packets.
[0024] As movie 1 is stored in these 5985 packet long extents, a fractional packet accumulation occurs that, if not compensated for, would add substantial amount of buffer memory needed to process a movie within a decoder. In the example and as shown at reference number 208 , a 0.96 fraction of a packet is accumulated with each extent such that after 2 extents more than full packet of accumulation occurs, i.e., 1.92 packets. To minimize the size of the buffer memory in the server, the invention compensates for the accumulation by making the 5986 th packet a null packet after a full packet of accumulation occurs. Without such null packet utilization, the buffer memory would accumulate a substantial number of packets, since the access controller would be providing more packets than are sent to users. In this example, after 2 extents have been stored, the 3rd extent (E 3 ) contains a null packet (P null ). The null packet used for accumulation compensation is referred to as a dither null packet to differentiate the packet from a standard null packet that may appear in an MPEG stream.
[0025] The access controller maintains a sum of the fractional packet accumulation. As such, a fractional packet accumulation value is computed and, when a null packet is used, one packet is subtracted from the accumulation value and the remainder is used as the accumulation value to which additional fractional packet values are added. In the example above, the first extent fractional value is 0.96 and the accumulated value after the second extent is 1.92 (i.e., 0.96 plus 0.96). Then, one dither null packet is used and the accumulation value falls to 0.92, but the third packet adds a 0.96 fractional packet to the accumulation value causing the accumulation value to rise to 1.88. As such, the fourth extent will contain a dither null packet. This process is repeated until the entire movie is stored in memory.
[0026] The present invention typically stores packets that have a header in which a special code is used to identify a dither null packet. This code is used to ensure that the dither null packets are removed from the data before the data is sent to a user. Sending such null packets would use bandwidth in the transmission channel for no reason. The removal of dither null packets is described below.
[0027] These extents are striped onto the disk array as shown in striping map 206 , where movie 1 , extent 1 (M 1 E 1 ) is stored on disk drive 1 (D 1 ), then M 1 E 2 is stored on D 2 and so on.
[0028] If, for example and as shown at 202 , the bit rate for movie 2 (M 2 ) is 6 Mbps and the service period is 1.8 seconds, then the extent size will be 7180.85 packets (assuming 188 byte MPEG packets are used to carry the data). The process rounds up to the next full packet, to an extent size is 7181 packets. As movie 2 is stored in these 7181 packet long extents, the fractional packet accumulation is a 0.15 fraction of a packet for each extent such that after 6 extents a full packet of accumulation occurs. The invention, as shown at 204 , compensates for the fractional packet accumulation by using a dither null packet after a full packet of accumulation occurs. In this example, after 6 extents have been stored, the 7th extent (E 7 ) uses a dither null packet (P null ). The extents for movie 2 are stored on the disk drive array as shown in the striping map 206 .
[0029] Using null packets in this manner, any arbitrary bit rate packet stream can be easily stored and the server uses a minimal sized buffer.
[0030] Returning to FIG. 1, upon a request for delivery of programming to a user, the program extents are recalled from the disk drives by the access controller 108 . The extents are buffered in buffer 110 . Since the server is simultaneously processing and fulfilling request form many users, the access controller interleaves the extent accesses of the various requested movies. Although the extents for a requested movie are generally accessed sequentially, they are not accessed contiguously. As such, a given movie's extents are placed in the buffer interspersed with other movie's extents. In fact, to minimize buffer size, an extent for a given movie is not added to the buffer until the previous extent has been read out of the buffer and sent to the user.
[0031] As the extents are stored in the buffer 110 , the access controller monitors the packet headers within the extents to detect dither null packets. Once identified, the pointer that is used to access the packets for transfer to the multiplexer 112 is instructed to skip the dither null packets. As such, the dither null packets are not transferred to the multiplexer 112 .
[0032] The multiplexer 112 is provided the buffered packets as needed to maintain a steady video signal at a user's television. The individual packets from the buffer 110 are positioned into a transport stream along with packets of many other programs. The transport stream is transmitted along with as many as 270 other streams through a 1 G bps fiber optic channel to the user. The user's equipment extracts from the transport stream the packets associated with the requested program, decodes the packets, and displays the program.
[0033] [0033]FIG. 3 shows a flow diagram of a routine 300 for storing multiple constant bit rate (MCBR) data streams into a memory. The routine 300 begins with a start signal at step 302 . The routine 300 then proceeds to step 304 to determine the extent size to use for the MCBR stream. As discussed above, the extent size (E) is the bit rate (BR) of the stream times the service interval (T s ) (i.e., the time required to read an extent from a disk drive to fulfill a user request).
[0034] The routine 300 then proceeds to step 308 to determine which of the extents will receive a dither null packet. The process maintains an accumulation value, as described above. This accumulation value is the sum of the fractional packet value that is contained in each extent. When the accumulation value reaches a value that is greater than or equal to one, a dither null packet is used. This reduces the accumulation value by one and the remainder is then used as the accumulation value to which the following extent's fractional value is added. Thus, step 308 uses the accumulation value to determine which of the extents will contain a dither null packet. used
[0035] At step 310 , the server 102 stores the data stream into the extents as defined in step 306 and inserts dither null packets in the extents as determined in step 308 . The extents are striped across the array as discussed with respect to FIG. 2.
[0036] After storing the extents, the routine 300 proceeds to step 312 to determine whether there are any more data streams to be stored. If there is additional data to receive, then the routine 300 returns to step 304 to receive and store an additional data stream. If there is no additional data to receive, then the routine 300 proceeds to step 314 to stop the storage of MCBR data streams.
[0037] The numerical values used herein in FIGS. 1 to 3 are illustrative and are not intended as limiting the invention. As such, other values and standards may be used without affecting the scope of the invention.
[0038] Although various embodiments which incorporate the teachings of the present invention have been shown and described in detail herein, those skilled in the art can readily devise many other varied embodiments that still incorporate these teachings.
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A method of defining extent for storing a plurality data streams having different bit rates. The method calculates the size of the extent for a given data stream then periodically inserts at least one null packet into the extents to enable any bit rate to be able to be stored using a fixed extent size for the stream.
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BACKGROUND OF THE INVENTION
The invention relates to a method for treating a photosensitive material by conveying the material vertically with a U-turn in a treating bath in which a treating liquid is circulated and an apparatus for practicing the method. The invention also relates particularly to the flow of the treating liquid in the treating bath.
In the case where a photosensitive material is treated by conveying it through a treating bath in which a treating liquid is circulated, it is difficult to finish the photosensitive material with a uniform density and uneven developing results if the treating liquid near the photosensitive material is exhausted. In order to prevent uneven developing, it is necessary to permit the treating liquid to flow continuously. In the treatment of ordinary photographic photosensitive materials or X-ray films, good results can be obtained if the treating liquid is maintained in motion. When it is necessary to add supplemental liquid, uneven developing can be prevented by uniformly mixing the supplemental liquid in the treating liquid in the treating bath.
In treating a graphic arts-type photosensitive material such as a lithographic film in which the picture density is expressed as variations in dot area, the preferred developing method employs infectious development. Accordingly, it is difficult to finish the photosensitive material with a uniform density because of the non-uniform velocity of the treating liquid on the surface of the photosensitive material caused by circulation of the treating liquid and because of eddies formed in the treating liquid. Especially, as the width of the photosensitive material increases, this particular difficulty becomes more prominent.
In order to prevent such uneven developing, a method has been previously employed in the art in which concentration of exhausted treating liquid near a film surface is prevented. In another conventional method for preventing uneven developing, the treating liquid is allowed to flow to the extent that no exhausted treating liquid remains near the film surface and no turbulence is permitted in the flow of treating liquid. In most of these conventional methods, a film is conveyed by means of a rack including plural rollers which are supported between side boards and a treating liquid discharging pipe and a treating liquid withdrawal pipe are provided inside the rack in order to obtain a uniform flow of treating liquid for the surface of the film. Accordingly, it is substantially essential to use such a rack in the conventional method.
One example of a conventional method in which a treating liquid is withdrawn into the inside of a rack so as to provide a uniform liquid flow on the surface of a film is shown in FIG. 1 and FIG. 2. Feeding rollers 1, guides 2, flow regulating boards 3 serving also as guides, and a suction chamber 4 are provided between side boards 5. The suction chamber 4 is provided with a number of liquid withdrawal inlets 6 adapted to withdraw the liquid by suction between the flow regulating boards 3 and a conveyed film P. Circulation of the treating liquid is as shown in FIG. 2. That is, the treating liquid supplied by a circulating pump 7 passes through a filter 8 and enters a temperature control chamber 10 provided at the bottom of a treating bath 9. The temperature of the liquid in the temperature control chamber 10 is controlled by a temperature control system including a heater 11, a cooling pipe 1 and a thermistor 13. The temperature controlled liquid introduced through a liquid discharging outlet 14 into the treating bath 9. The treating liquid in the treating bath flows between the film P conveyed as shown in FIG. 1 and the flow regulating boards 3 in the rack (not shown in FIG. 2) and circulates by force of the suction pressure provided through withdrawal inlets 6. The treating liquid is supplemented by supplying additional treating liquid to the treating liquid circulating path through a supplementing pipe 15. Excess amounts of treating liquid are discharged by overflow. The discharge of the treating liquid in the system is carried out by operating a discharge valve 16.
An example of a method in which treating liquid is discharged from the inside of a rack to provide a uniform liquid flow on the surface of a film is as shown in FIGS. 3 and 4. That is, feeding rollers 1, guides 2, and a liquid discharging pipe 17 are disposed between side boards 5. The liquid discharging pipe 17 is provided with a number of liquid discharging outlets 18 so as to provide a uniform liquid flow on the surface of a conveyed film. Circulation of the treating liquid is such that the liquid is delivered by a pump (not shown) and subjected to temperature control by a temperature control system after which the liquid thus processed is supplied to the liquid discharging pipe 17 to be discharged through the liquid discharging outlets 18. Furthermore, the treating liquid in a treating bath 9 is circulated through a liquid withdrawal inlets 19.
The apparatus for implementing these conventional methods are intricate in construction and accordingly difficult to manufacture. The method illustrated in FIGS. 1 and 2 in which a number of liquid withdrawal inlets are provided inside the rack is advantageous in that the direction and velocity of the flow of treating liquid are uniform on the surface of the film. However, it is still disadvantageous in that uneven developing is caused because the film is attracted towards the liquid withdrawal inlets 6 thus bringing the film into contact with the guides or the flow regulating boards 3. Furthermore, the method is disadvantageous in the following points. First, if the liquid flow openings 20A of the suction chamber 4 are completely connected to the liquid flowing openings 20B of the liquid treating bath 9, it is then difficult to disconnect the suction chamber 4 from the bath 9 for inspecting and cleaning the rack. If these openings 20A and 20B are not completely connected to one another, then the liquid leaks as a result of which the efficiency of feeding the liquid through the liquid withdrawal inlets 6 decreases. Furthermore, since a number of liquid withdrawal inlets 6 having a small diameter and a number of liquid regulating boards 3 are used, the resistance to the flow of liquid is high and, accordingly, the pump for circulating the treating liquid must be a high head.
The method described with reference to FIGS. 3 and 4 in which a number of liquid discharging outlets 18 are provided inside the rack is also disadvantageous in that the position of the liquid discharging pipe 17 and the diameter and orientation of the liquid discharging outlets 18 must be determined carefully. In addition, the method suffers from the same problems as those suffered by the method using the liquid withdrawal inlets 8 described above. Moreover, the apparatus for practicing these conventional methods are also disadvantageous in that they are intricate in construction and accordingly high in manufacturing cost.
Accordingly, an object of the invention is to provide a method by which a flow of liquid suitable for treating a graphic arts process photosensitive material can be maintained at the surface of the material without employing a conventional intricate method in which the liquid withdrawal or discharging openings are provided inside the rack. It is also an object of the invention to provide an apparatus for practicing this method.
SUMMARY OF THE INVENTION
The foregoing objects and other objects of the invention have been achieved by the provision of a method for treating a graphic arts process photosensitive material by conveying the photosensitive material vertically with a U-turn in a treating bath in which a treating liquid is circulated, in which method, according to the invention, the photosensitive material is conveyed with the photosensitive layer thereof facing outwardly and with the flow of the treating liquid directed along the photosensitive layer surface of the photosensitive material substantially perpendicular to the direction of conveyance of the photosensitive material. There is also provided in accordance with the invention an apparatus for implementing the method, that is an apparatus for treating a graphic arts process photosensitive material by conveying the photosensitive material vertically with a U-turn in a treating bath in which a treating liquid is circulated, in which apparatus, according to the invention, a space is provided between the bottom of the treating bath and a part of the photosensitive material at which the photosensitive material makes the U-turn so that the treating liquid flows therein. A liquid discharging pipe is provided which is adapted to discharge the treating liquid into a liquid pool formed in the space in such a manner that the treating liquid flows from one side wall of the treating bath to the other side wall thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side view showing the essential components of a rack employed in a conventional treating apparatus;
FIG. 2 is a front view showing a section of a liquid suction chamber and a treating bath in the apparatus of FIG. 1 and a circulation system thereof;
FIG. 3 is a side view showing the essential components of a rack employed in another conventional treating apparatus;
FIG. 4 is a front view showing a section of the rack, a liquid discharging pipe of the rack and a treating bath in the apparatus shown in FIG. 3;
FIG. 5 is a front view showing components of a treating apparatus according to the invention;
FIG. 6 is a sectional view taken along the line VI--VI in FIG. 5;
FIG. 7 is a side view of the apparatus shown in FIG. 5; and
FIG. 8 is a sectional view of the apparatus of FIGS. 5-7 showing the flow of the treating liquid therein.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The invention will be described in detail with reference to FIGS. 5 through 8 which illustrate an example of an apparatus for treating a graphic arts process photosensitive material according to the invention.
FIGS. 5 through 7 show the relation between a treating bath and a rack in the apparatus according to the invention. More specifically, FIG. 5 is a front view, partly as a sectional view, of the bath and the rack while FIG. 6 is a sectional view taken along the line VI--VI in FIG. 5 and FIG. 7 is a side view.
In the example shown in these figures, the rack includes feed rollers 1 arranged along three lines. The rollers 1 are rotatably mounted on side boards 5. The shafts of the rollers 1 are connected through gears (not shown) so that they can be rotated by a drive means (not shown). A lithographic film P is inserted between the rollers 1 on the center line and the rollers 1 provided outside them to the left in the view of FIG. 6. The feed roller 1 provided in the U-turn section of the rack is larger in diameter so that the lithographic film P can make a gradual U-turn at that position. Film guides (not shown) are provided between the feed rollers and at the U-turn section. The film guides other than those at the U-turn section are in the form of a comb so that the treating liquid can pass therethrough. The side boards 5 have apertures in the form of through-holes 21 through which the treating liquid can readily pass. The through-holes 21 are positioned outside the film path and the area of each through-hole 21 is made as large as possible so that the treating liquid can readily pass therethrough. Instead of the through-holes 21, slots may be employed. In that case, it is preferable that the slots do not greatly overlap the positions of the rollers.
In a treating bath 9, the rack is sufficiently spaced from the bottom of the treating bath 9 so that the treating liquid can freely flow therein. The treating bath 9 is provided with a liquid discharging pipe 14 adapted to introduce the liquid into a liquid pool in the space formed by the rack and the bottom of the treating bath and a liquid withdrawal pipe 19 adapted to return the treating liquid from the treating bath 9 to a circulating pump.
It is necessary that the space between the rack and the bottom of the treating bath be at least 40 mm, preferably 80 mm, depending on the width of the lithographic film P to be treated. In this example, the space is about 80 mm for treating a film having a width of about 635 mm. Preferably, the flow rate of the treating liquid discharged through the liquid discharging inlet 14 is about 30 cm/sec. With a total quantity of treating liquid in the treating bath of 40 liters, the total flow rate of circulating liquid is of the order of 10 liters/min which is about half of that necessary in the conventional treating method. As for the through-holes 21 of the rack, the positions of the liquid withdrawal pipes 19 are outside the film path. The most suitable positions of the pipes 19 depend on various factors such as the length of the rack and the arrangement of the rollers. However, a preferable result can be obtained by providing one pipe 14 at a height of about 10 to 30% of the total height of the device and another pipe 19 at a height of about 55 to 75% of the total height.
In the treating bath 9, the treating liquid flows outside the rollers generally as indicated by the arrows in FIG. 8. As a result of this flow of treating liquid in the in the treating bath, a secondary flow of treating liquid in the form of laminar flow is produced on the surface of the film and in the vicinity thereof. This secondary flow makes it possible to provide a uniform development density. The liquid withdrawal pipe 19 may be provided at a position opposite to the position of the liquid discharging inlet as indicated by the chain line 19'. In this case, the general flow of liquid is substantially similar to that described above and substantially the same effect can be obtained.
The general circulation of treating liquid in the treating bath is indicated by the arrows in FIG. 8. That is, the flow A moves from one side wall of the treating bath to the other side wall between the bottom of the treating bath and the photosensitive material which is conveyed while making the U-turn, the flow B moves upwardly along the edge of the photosensitive material which is conveyed vertically, the flow C moves from the other side wall of the treating bath to the one side wall along the surface of the photosensitive material, and the flow D moves downwardly along the edge of the photosensitive material as has been confirmed experimentally. The fact that the secondary flow is in the form of laminar flow on the surface of the photosensitive material and in the vicinity thereof has also been confirmed experimentally. However, the precise reasons why such a phenomena occurs are not understood as yet. This however, in no manner detracts from the usefulness of the invention.
A preferred method of treating a graphic arts process photosensitive material and an apparatus for practicing the method according to the invention have been described above. In accordance with this method and apparatus, the amount of treating liquid circulated by continuous withdrawal and discharge is of the order of half of that required by the conventional method in which the treating liquid is discharged from inside the rack or withdrawn into the inside of the rack.
In the case where a rack is employed in which rollers are arranged in three lines, it is difficult to effectively carry out the discharging and withdrawal of the treating liquid inside the rack. However, this difficulty can be eliminated by employing the method according to the invention.
Furthermore, in the conventional method, if the type rack is changed, then it is necessary to modify or adjust the various components thereof in order to effectively withdraw or discharge the treating liquid. On the other hand, in the present invention, irrespective of the construction of the rack, photosensitive material can be finished with a uniform density and, accordingly, the apparatus can be easily designed and manufactured.
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A method and apparatus for uniformly developing a graphic arts process photosensitive film by producing a uniform laminar flow of treating liquid over the surface of the film as it passes through a treatment bath. The film is conveyed vertically on a rack through the bath with a U-turn near the bottom. Treatment fluid is flowed horizontally below the U-turn. Discharge and withdrawal pipes in the treatment bath container and apertures in the rack positioned at disclosed preferred locations provide the desired flow pattern.
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RELATED APPLICATIONS
[0001] This application is a continuation of U.S. application Ser. No. 12/366,508, filed Feb. 5, 2009, entitled SELF-TREPHINING IMPLANT AND METHODS THEREOF FOR TREATMENT OF OCULAR DISORDERS, which is a divisional of U.S. patent application Ser. No. 11/598,542, filed Nov. 13, 2006, entitled IMPLANT AND METHODS THEREOF FOR TREATMENT OF OCULAR DISORDERS, which is a continuation of U.S. patent application Ser. No. 10/118,578, filed Apr. 8, 2002, entitled GLAUCOMA STENT AND METHODS THEREOF FOR GLAUCOMA TREATMENT, now U.S. Pat. No. 7,135,009 B2, issued Nov. 14, 2006, which claims the benefit of U.S. Provisional Application No. 60/281,973, filed Apr. 7, 2001, entitled GLAUCOMA SHUNT AND METHODS THEREOF FOR GLAUCOMA TREATMENT, the entire contents of which are hereby incorporated by reference herein.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The invention relates generally to medical devices and methods for reducing the intraocular pressure in an animal eye and, more particularly, to shunt type devices for permitting aqueous outflow from the eye's anterior chamber and associated methods thereof for the treatment of glaucoma.
[0004] 2. Description of the Related Art
[0005] The human eye is a specialized sensory organ capable of light reception and able to receive visual images. The trabecular meshwork serves as a drainage channel and is located in anterior chamber angle formed between the iris and the cornea. The trabecular meshwork maintains a balanced pressure in the anterior chamber of the eye by draining aqueous humor from the anterior chamber.
[0006] About two percent of people in the United States have glaucoma. Glaucoma is a group of eye diseases encompassing a broad spectrum of clinical presentations, etiologies, and treatment modalities. Glaucoma causes pathological changes in the optic nerve, visible on the optic disk, and it causes corresponding visual field loss, resulting in blindness if untreated. Lowering intraocular pressure is the major treatment goal in all glaucomas.
[0007] In glaucomas associated with an elevation in eye pressure (intraocular hypertension), the source of resistance to outflow is mainly in the trabecular meshwork. The tissue of the trabecular meshwork allows the aqueous humor (“aqueous”) to enter Schlemm's canal, which then empties into aqueous collector channels in the posterior wall of Schlemm's canal and then into aqueous veins, which form the episcleral venous system. Aqueous humor is a transparent liquid that fills the region between the cornea, at the front of the eye, and the lens. The aqueous humor is continuously secreted by the ciliary body around the lens, so there is a constant flow of aqueous humor from the ciliary body to the eye's front chamber. The eye's pressure is determined by a balance between the production of aqueous and its exit through the trabecular meshwork (major route) or uveal scleral outflow (minor route). The trabecular meshwork is located between the outer rim of the iris and the back of the cornea, in the anterior chamber angle. The portion of the trabecular meshwork adjacent to Schlemm's canal (the juxtacanilicular meshwork) causes most of the resistance to aqueous outflow.
[0008] Glaucoma is grossly classified into two categories: closed-angle glaucoma, also known as angle closure glaucoma, and open-angle glaucoma. Closed-angle glaucoma is caused by closure of the anterior chamber angle by contact between the iris and the inner surface of the trabecular meshwork. Closure of this anatomical angle prevents normal drainage of aqueous humor from the anterior chamber of the eye.
[0009] Open-angle glaucoma is any glaucoma in which the angle of the anterior chamber remains open, but the exit of aqueous through the trabecular meshwork is diminished. The exact cause for diminished filtration is unknown for most cases of open-angle glaucoma. Primary open-angle glaucoma is the most common of the glaucomas, and it is often asymptomatic in the early to moderately advanced stage. Patients may suffer substantial, irreversible vision loss prior to diagnosis and treatment. However, there are secondary open-angle glaucomas which may include edema or swelling of the trabecular spaces (e.g., from corticosteroid use), abnormal pigment dispersion, or diseases such as hyperthyroidism that produce vascular congestion.
[0010] Current therapies for glaucoma are directed at decreasing intraocular pressure. Medical therapy includes topical ophthalmic drops or oral medications that reduce the production or increase the outflow of aqueous. However, these drug therapies for glaucoma are sometimes associated with significant side effects, such as headache, blurred vision, allergic reactions, death from cardiopulmonary complications, and potential interactions with other drugs. When drug therapy fails, surgical therapy is used. Surgical therapy for open-angle glaucoma consists of laser trabeculoplasty, trabeculectomy, and implantation of aqueous shunts after failure of trabeculectomy or if trabeculectomy is unlikely to succeed. Trabeculectomy is a major surgery that is widely used and is augmented with topically applied anticancer drugs, such as 5-flurouracil or mitomycin-C to decrease scarring and increase the likelihood of surgical success.
[0011] Approximately 100,000 trabeculectomies are performed on Medicare-age patients per year in the United States. This number would likely increase if the morbidity associated with trabeculectomy could be decreased. The current morbidity associated with trabeculectomy consists of failure (10-15%); infection (a life long risk of 2-5%); choroidal hemorrhage, a severe internal hemorrhage from low intraocular pressure, resulting in visual loss (1%); cataract formation; and hypotony maculopathy (potentially reversible visual loss from low intraocular pressure).
[0012] For these reasons, surgeons have tried for decades to develop a workable surgery for the trabecular meshwork.
[0013] The surgical techniques that have been tried and practiced are goniotomy/trabeculotomy and other mechanical disruptions of the trabecular meshwork, such as trabeculopuncture, goniophotoablation, laser trabecular ablation, and goniocurretage. These are all major operations and are briefly described below.
[0014] Goniotomy/Trabeculotomy: Goniotomy and trabeculotomy are simple and directed techniques of microsurgical dissection with mechanical disruption of the trabecular meshwork. These initially had early favorable responses in the treatment of open-angle glaucoma. However, long-term review of surgical results showed only limited success in adults. In retrospect, these procedures probably failed due to cellular repair and fibrosis mechanisms and a process of “filling in.” Filling in is a detrimental effect of collapsing and closing in of the created opening in the trabecular meshwork. Once the created openings close, the pressure builds back up and the surgery fails.
[0015] Trabeculopuncture: Q-switched Neodynium (Nd) YAG lasers also have been investigated as an optically invasive technique for creating full-thickness holes in trabecular meshwork. However, the relatively small hole created by this trabeculopuncture technique exhibits a filling-in effect and fails.
[0016] Goniophotoablation/Laser Trabecular Ablation: Goniophotoablation is disclosed by Berlin in U.S. Pat. No. 4,846,172 and involves the use of an excimer laser to treat glaucoma by ablating the trabecular meshwork. This was demonstrated not to succeed by clinical trial. Hill et al. used an Erbium:YAG laser to create full-thickness holes through trabecular meshwork (Hill et al., Lasers in Surgery and Medicine 11:341-346, 1991). This technique was investigated in a primate model and a limited human clinical trial at the University of California, Irvine. Although morbidity was zero in both trials, success rates did not warrant further human trials. Failure was again from filling in of surgically created defects in the trabecular meshwork by repair mechanisms. Neither of these is a viable surgical technique for the treatment of glaucoma.
[0017] Goniocurretage: This is an ab interno (from the inside), mechanically disruptive technique that uses an instrument similar to a cyclodialysis spatula with a microcurrette at the tip. Initial results were similar to trabeculotomy: it failed due to repair mechanisms and a process of filling in.
[0018] Although trabeculectomy is the most commonly performed filtering surgery, viscocanulostomy (VC) and non-penetrating trabeculectomy (NPT) are two new variations of filtering surgery. These are ab externo (from the outside), major ocular procedures in which Schlemm's canal is surgically exposed by making a large and very deep scleral flap. In the VC procedure, Schlemm's canal is cannulated and viscoelastic substance injected (which dilates Schlemm's canal and the aqueous collector channels). In the NPT procedure, the inner wall of Schlemm's canal is stripped off after surgically exposing the canal.
[0019] Trabeculectomy, VC, and NPT involve the formation of an opening or hole under the conjunctiva and scleral flap into the anterior chamber, such that aqueous humor is drained onto the surface of the eye or into the tissues located within the lateral wall of the eye. These surgical operations are major procedures with significant ocular morbidity. When trabeculectomy, VC, and NPT are thought to have a low chance for success, a number of implantable drainage devices have been used to ensure that the desired filtration and outflow of aqueous humor through the surgical opening will continue. The risk of placing a glaucoma drainage device also includes hemorrhage, infection, and diplopia (double vision).
[0020] Examples of implantable shunts and surgical methods for maintaining an opening for the release of aqueous humor from the anterior chamber of the eye to the sclera or space beneath the conjunctiva have been disclosed in, for example, U.S. Pat. No. 6,059,772 to Hsia et al., and U.S. Pat. No. 6,050,970 to Baerveldt.
[0021] All of the above surgeries and variations thereof have numerous disadvantages and moderate success rates. They involve substantial trauma to the eye and require great surgical skill in creating a hole through the full thickness of the sclera into the subconjunctival space. The procedures are generally performed in an operating room and have a prolonged recovery time for vision.
[0022] The complications of existing filtration surgery have prompted ophthalmic surgeons to find other approaches to lowering intraocular pressure.
[0023] The trabecular meshwork and juxtacanilicular tissue together provide the majority of resistance to the outflow of aqueous and, as such, are logical targets for surgical removal in the treatment of open-angle glaucoma. In addition, minimal amounts of tissue are altered and existing physiologic outflow pathways are utilized.
[0024] As reported in Arch. Ophthalm. (2000) 118:412, glaucoma remains a leading cause of blindness, and filtration surgery remains an effective, important option in controlling the disease. However, modifying existing filtering surgery techniques in any profound way to increase their effectiveness appears to have reached a dead end. The article further states that the time has come to search for new surgical approaches that may provide better and safer care for patients with glaucoma.
[0025] Therefore, there is a great clinical need for a method of treating glaucoma that is faster, safer, and less expensive than currently available modalities.
SUMMARY OF THE INVENTION
[0026] The trabecular meshwork and juxtacanilicular tissue together provide the majority of resistance to the outflow of aqueous and, as such, are logical targets for surgical approach in the treatment of glaucoma. Various embodiments of glaucoma shunts are disclosed herein for aqueous to exit through the trabecular meshwork (major route) or uveal scleral outflow (minor route) or other route effective to reduce intraocular pressure (TOP).
[0027] Glaucoma surgical morbidity would greatly decrease if one were to bypass the focal resistance to outflow of aqueous only at the point of resistance, and to utilize remaining, healthy aqueous outflow mechanisms. This is in part because episcleral aqueous humor exerts a backpressure that prevents intraocular pressure from going too low, and one could thereby avoid hypotony. Thus, such a surgery would virtually eliminate the risk of hypotony-related maculopathy and choroidal hemorrhage. Furthermore, visual recovery would be very rapid, and the risk of infection would be very small, reflecting a reduction in incidence from 2-5% to about 0.05%.
[0028] Copending U.S. application Ser. No. 09/549,350, filed Apr. 14, 2000, entitled APPARATUS AND METHOD FOR TREATING GLAUCOMA, and copending U.S. application Ser. No. 09/704,276, filed Nov. 1, 2000, entitled GLAUCOMA TREATMENT DEVICE, disclose devices and methods of placing a trabecular shunt ab interno, i.e., from inside the anterior chamber through the trabecular meshwork, into Schlemm's canal. The entire contents of each one of these copending patent applications are hereby incorporated by reference herein. The invention encompasses both ab interno and ab externo glaucoma shunts or stents and methods thereof.
[0029] Techniques performed in accordance with aspects herein may be referred to generally as “trabecular bypass surgery.” Advantages of this type of surgery include lowering intraocular pressure in a manner which is simple, effective, disease site-specific, and can potentially be performed on an outpatient basis.
[0030] Generally, trabecular bypass surgery (TBS) creates an opening, a slit, or a hole through trabecular meshwork with minor microsurgery. TBS has the advantage of a much lower risk of choroidal hemorrhage and infection than prior techniques, and it uses existing physiologic outflow mechanisms. In some aspects, this surgery can potentially be performed under topical or local anesthesia on an outpatient basis with rapid visual recovery. To prevent “filling in” of the hole, a biocompatible elongated device is placed within the hole and serves as a stent. U.S. patent application Ser. No. 09/549,350, filed Apr. 14, 2000, the entire contents of which are hereby incorporated by reference herein, discloses trabecular bypass surgery.
[0031] As described in U.S. patent application Ser. No. 09/549,350, filed Apr. 14, 2000, and U.S. application Ser. No. 09/704,276, filed Nov. 1, 2000, the entire contents each one of which are hereby incorporated by reference herein, a trabecular shunt or stent for transporting aqueous humor is provided. The trabecular stent includes a hollow, elongate tubular element, having an inlet section and an outlet section. The outlet section may optionally include two segments or elements, adapted to be positioned and stabilized inside Schlemm's canal. In one embodiment, the device appears as a “T” shaped device.
[0032] In one aspect of the invention, a delivery apparatus (or “applicator”) is used for placing a trabecular stent through a trabecular meshwork of an eye. Certain embodiments of such a delivery apparatus are disclosed in copending U.S. application Ser. No. 10/101,548 (Inventors: Gregory T. Smedley, Irvine, Calif., Morteza Gharib, Pasadena, Calif., Hosheng Tu, Newport Beach, Calif.; Attorney Docket No.: GLAUKO.012A), filed Mar. 18, 2002, entitled APPLICATOR AND METHODS FOR PLACING A TRABECULAR SHUNT FOR GLAUCOMA TREATMENT, and U.S. Provisional Application No. 60/276,609, filed Mar. 16, 2001, entitled APPLICATOR AND METHODS FOR PLACING A TRABECULAR SHUNT FOR GLAUCOMA TREATMENT, the entire contents of each one of which are hereby incorporated by reference herein.
[0033] The stent has an inlet section and an outlet section. The delivery apparatus includes a handpiece, an elongate tip, a holder and an actuator. The handpiece has a distal end and a proximal end. The elongate tip is connected to the distal end of the handpiece. The elongate tip has a distal portion and is configured to be placed through a corneal incision and into an anterior chamber of the eye. The holder is attached to the distal portion of the elongate tip. The holder is configured to hold and release the inlet section of the trabecular stent. The actuator is on the handpiece and actuates the holder to release the inlet section of the trabecular stent from the holder. When the trabecular stent is deployed from the delivery apparatus into the eye, the outlet section is positioned in substantially opposite directions inside Schlemm's canal. In one embodiment, a deployment mechanism within the delivery apparatus includes a push-pull type plunger.
[0034] Some aspects of the invention relate to devices for reducing intraocular pressure by providing outflow of aqueous from an anterior chamber of an eye. The device generally comprises an elongated tubular member and cutting means. The tubular member is adapted for extending through a trabecular meshwork of the eye. The tubular member generally comprises a lumen having an inlet port and at least one outlet port for providing a flow pathway. The cutting means is mechanically connected to or is an integral part of the tubular member for creating an incision in the trabecular meshwork for receiving at least a portion of the tubular member.
[0035] In one aspect, a self-trephining glaucoma stent is provided for reducing and/or balancing intraocular pressure in an eye. The stent generally comprises a snorkel and a curved blade. The snorkel generally comprises an upper seat for stabilizing said stent within the eye, a shank and a lumen. The shank is mechanically connected to the seat and is adapted for extending through a trabecular meshwork of the eye. The lumen extends through the snorkel and has at least one inlet flow port and at least one outlet flow port. The blade is mechanically connected to the snorkel. The blade generally comprises a cutting tip proximate a distal-most point of the blade for making an incision in the trabecular meshwork for receiving the shank.
[0036] Some aspects of the invention relate to methods of implanting a trabecular stent device in an eye. In one aspect, the device has a snorkel mechanically connected to a blade. The blade is advanced through a trabecular meshwork of the eye to cut the trabecular meshwork and form an incision therein. At least a portion of the snorkel is inserted in the incision to implant the device in the eye.
[0037] Some aspects provide a self-trephining glaucoma stent and methods thereof which advantageously allow for a “one-step” procedure in which the incision and placement of the stent are accomplished by a single device and operation. This desirably allows for a faster, safer, and less expensive surgical procedure. In any of the embodiments, fiducial markings, indicia, or the like and/or positioning of the stent device in a preloaded applicator may be used for proper orientation and alignment of the device during implantation.
[0038] Among the advantages of trabecular bypass surgery is its simplicity. The microsurgery may potentially be performed on an outpatient basis with rapid visual recovery and greatly decreased morbidity. There is a lower risk of infection and choroidal hemorrhage, and there is a faster recovery, than with previous techniques.
[0039] For purposes of summarizing the invention, certain aspects, advantages and novel features of the invention have been described herein above. Of course, it is to be understood that not necessarily all such advantages may be achieved in accordance with any particular embodiment of the invention. Thus, the invention may be embodied or carried out in a manner that achieves or optimizes one advantage or group of advantages as taught or suggested herein without necessarily achieving other advantages as may be taught or suggested herein.
[0040] All of these embodiments are intended to be within the scope of the invention herein disclosed. These and other embodiments of the invention will become readily apparent to those skilled in the art from the following detailed description of the preferred embodiments having reference to the attached figures, the invention not being limited to any particular preferred embodiment(s) disclosed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0041] Having thus summarized the general nature of the invention and some of its features and advantages, certain preferred embodiments and modifications thereof will become apparent to those skilled in the art from the detailed description herein having reference to the figures that follow, of which:
[0042] FIG. 1 is a coronal cross-sectional view of an eye;
[0043] FIG. 2 is an enlarged cross-sectional view of an anterior chamber angle of the eye of FIG. 1 ;
[0044] FIG. 3 is a simplified partial view of an eye illustrating the implantation of a glaucoma stent having features and advantages in accordance with one embodiment of the invention;
[0045] FIG. 4 is a side elevation view of the stent of FIG. 3 ;
[0046] FIG. 5 is a top plan view of the stent of FIG. 3 ;
[0047] FIG. 6 is a bottom plan view of the stent of FIG. 3 ;
[0048] FIG. 7 is a front end view of the stent of FIG. 3 (along line 7 - 7 of FIG. 4 );
[0049] FIG. 8 is a rear end view of the stent of FIG. 3 (along line 8 - 8 of FIG. 4 );
[0050] FIG. 9 is an enlarged top plan view of a cutting tip of the stent of FIG. 3 ;
[0051] FIG. 10 is a top plan view of one exemplary embodiment of a snorkel top seating surface;
[0052] FIG. 11 is a top plan view of another exemplary embodiment of a snorkel top seating surface;
[0053] FIG. 12 is a top plan view of yet another exemplary embodiment of a snorkel top seating surface;
[0054] FIG. 13 is a top plan view of still another exemplary embodiment of a snorkel top seating surface;
[0055] FIG. 14 is a simplified partial view of an eye illustrating the implantation of a glaucoma stent having features and advantages in accordance with another embodiment of the invention;
[0056] FIG. 15 is a simplified partial view of an eye illustrating the implantation of a glaucoma stent having features and advantages in accordance with a further embodiment of the invention;
[0057] FIG. 16 is a side elevation view of a glaucoma stent having features and advantages in accordance with one embodiment of the invention;
[0058] FIG. 17 is a top plan view of the stent of FIG. 16 ;
[0059] FIG. 18 is a bottom plan view of the stent of FIG. 16 ;
[0060] FIG. 19 is a front end view along line 19 - 19 of FIG. 16 ;
[0061] FIG. 20 is a rear end view along line 20 - 20 of FIG. 16 ;
[0062] FIG. 21 is a side elevation view of a glaucoma stent having features and advantages in accordance with one embodiment of the invention;
[0063] FIG. 22 is a top plan view of the stent of FIG. 21 ;
[0064] FIG. 23 is a bottom plan view of the stent of FIG. 21 ;
[0065] FIG. 24 is a front end view along line 24 - 24 of FIG. 21 ;
[0066] FIG. 25 is a rear end view along line 25 - 25 of FIG. 21 ;
[0067] FIG. 26 is a front elevation view of a glaucoma stent having features and advantages in accordance with one embodiment of the invention;
[0068] FIG. 27 is a side elevation view along line 27 - 27 of FIG. 26 ;
[0069] FIG. 28 is a rear end view along line 28 - 28 of FIG. 26 ;
[0070] FIG. 29 is a simplified partial view of an eye illustrating the temporal implantation of a glaucoma stent using a delivery apparatus having features and advantages in accordance with one embodiment of the invention;
[0071] FIG. 30 is an oblique elevational view of an articulating arm stent delivery/retrieval apparatus having features and advantages in accordance with one embodiment of the invention;
[0072] FIG. 31 is a simplified partial view of an eye illustrating the implantation of a glaucoma stent using a delivery apparatus crossing through the eye anterior chamber;
[0073] FIG. 32 is a simplified partial view of an eye illustrating the implantation of a glaucoma stent having features and advantages in accordance with one embodiment of the invention;
[0074] FIG. 33 is a detailed enlarged view of the barbed pin of FIG. 32 ;
[0075] FIG. 34 is a simplified partial view of an eye illustrating the implantation of a glaucoma stent having features and advantages in accordance with one embodiment of the invention;
[0076] FIG. 35 is a simplified partial view of an eye illustrating the implantation of a glaucoma stent having features and advantages in accordance with one embodiment of the invention;
[0077] FIG. 36 is a simplified partial view of an eye illustrating the implantation of a glaucoma stent having features and advantages in accordance with one embodiment of the invention;
[0078] FIG. 37 is a simplified partial view of an eye illustrating the implantation of a glaucoma stent having features and advantages in accordance with one embodiment of the invention;
[0079] FIG. 38 is a simplified partial view of an eye illustrating the implantation of a glaucoma stent having features and advantages in accordance with one embodiment of the invention;
[0080] FIG. 39 is a simplified partial view of an eye illustrating the implantation of a glaucoma stent having features and advantages in accordance with one embodiment of the invention;
[0081] FIG. 40 is a simplified partial view of an eye illustrating the implantation of a glaucoma stent having features and advantages in accordance with one embodiment of the invention;
[0082] FIG. 41 is a simplified partial view of an eye illustrating the implantation of a glaucoma stent having features and advantages in accordance with one embodiment of the invention;
[0083] FIG. 42 is a simplified partial view of an eye illustrating the implantation of a glaucoma stent having features and advantages in accordance with one embodiment of the invention;
[0084] FIG. 43 is a simplified partial view of an eye illustrating the implantation of a valved tube stent device having features and advantages in accordance with one embodiment of the invention;
[0085] FIG. 44 is a simplified partial view of an eye illustrating the implantation of an osmotic membrane device having features and advantages in accordance with one embodiment of the invention;
[0086] FIG. 45 is a simplified partial view of an eye illustrating the implantation of a glaucoma stent using ab externo procedure having features and advantages in accordance with one embodiment of the invention;
[0087] FIG. 46 is a simplified partial view of an eye illustrating the implantation of a glaucoma stent having features and advantages in accordance with a modified embodiment of the invention; and
[0088] FIG. 47 is a simplified partial view of an eye illustrating the implantation of a drug release implant having features and advantages in accordance with one embodiment of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0089] The preferred embodiments of the invention described herein relate particularly to surgical and therapeutic treatment of glaucoma through reduction of intraocular pressure. While the description sets forth various embodiment specific details, it will be appreciated that the description is illustrative only and should not be construed in any way as limiting the invention. Furthermore, various applications of the invention, and modifications thereto, which may occur to those who are skilled in the art, are also encompassed by the general concepts described herein.
[0090] FIG. 1 is a cross-sectional view of an eye 10 , while FIG. 2 is a close-up view showing the relative anatomical locations of a trabecular meshwork 21 , an anterior chamber 20 , and Schlemm's canal 22 . A sclera 11 is a thick collagenous tissue which covers the entire eye 10 except a portion which is covered by a cornea 12 .
[0091] Referring to FIGS. 1 and 2 , the cornea 12 is a thin transparent tissue that focuses and transmits light into the eye and through a pupil 14 , which is a circular hole in the center of an iris 13 (colored portion of the eye). The cornea 12 merges into the sclera 11 at a juncture referred to as a limbus 15 . A ciliary body 16 extends along the interior of the sclera 11 and is coextensive with a choroid 17 . The choroid 17 is a vascular layer of the eye 10 , located between the sclera 11 and a retina 18 . An optic nerve 19 transmits visual information to the brain and is the anatomic structure that is progressively destroyed by glaucoma.
[0092] Still referring to FIGS. 1 and 2 , the anterior chamber 20 of the eye 10 , which is bound anteriorly by the cornea 12 and posteriorly by the iris 13 and a lens 26 , is filled with aqueous humor (hereinafter referred to as “aqueous”). Aqueous is produced primarily by the ciliary body 16 , then moves anteriorly through the pupil 14 and reaches an anterior chamber angle 25 , formed between the iris 13 and the cornea 12 .
[0093] As best illustrated by the drawing of FIG. 2 , in a normal eye, aqueous is removed from the anterior chamber 20 through the trabecular meshwork 21 . Aqueous passes through the trabecular meshwork 21 into Schlemm's canal 22 and thereafter through a plurality of aqueous veins 23 , which merge with blood-carrying veins, and into systemic venous circulation. Intraocular pressure is maintained by an intricate balance between secretion and outflow of aqueous in the manner described above. Glaucoma is, in most cases, characterized by an excessive buildup of aqueous in the anterior chamber 20 which leads to an increase in intraocular pressure. Fluids are relatively incompressible, and thus intraocular pressure is distributed relatively uniformly throughout the eye 10 .
[0094] As shown in FIG. 2 , the trabecular meshwork 21 is adjacent a small portion of the sclera 11 . Exterior to the sclera 11 is a conjunctiva 24 . Traditional procedures that create a hole or opening for implanting a device through the tissues of the conjunctiva 24 and sclera 11 involve extensive surgery by an ab externo procedure, as compared to surgery for implanting a device, as described herein, which ultimately resides entirely within the confines of the sclera 11 and cornea 12 .
Self-Trephining Glaucoma Stent
[0095] FIG. 3 generally illustrates the use of one embodiment of a trabecular stenting device 30 for establishing an outflow pathway, passing through the trabecular meshwork 21 , which is discussed in greater detail below. FIGS. 4-9 are different views of the stent 30 . Advantageously, and as discussed in further detail later herein, the self-trephining-stent allows a one-step procedure to make an incision in the trabecular mesh 21 and place the stent or implant 30 at the desired or predetermined position within the eye 10 . Desirably, this facilitates and simplifies the overall surgical procedure.
[0096] In the illustrated embodiment of FIGS. 3-9 , the shunt or stent 30 generally comprises a snorkel 32 and a main body portion or blade 34 . The snorkel 32 and blade 34 are mechanically connected to or in mechanical communication with one another. The stent 30 and/or the body portion 34 have a generally longitudinal axis 36 .
[0097] In the illustrated embodiment of FIGS. 3-9 , the stent 30 comprises an integral unit. In modified embodiments, the stent 30 may comprise an assembly of individual pieces or components. For example, the stent 30 may comprise an assembly of the snorkel 32 and blade 34 .
[0098] In the illustrated embodiment of FIGS. 3-9 , the snorkel 32 is in the form of a generally elongate tubular member and generally comprises an upper seat, head or cap portion 38 , a shank portion 40 and a lumen or passage 42 extending therethrough. The seat 38 is mechanically connected to or in mechanical communication with the shank 40 which is also mechanically connected to or in mechanical communication with the blade 34 . The snorkel 32 and/or the lumen 42 have a generally longitudinal axis 43 .
[0099] In the illustrated embodiment of FIGS. 3-9 , the seat 38 is generally circular in shape and has an upper surface 44 and a lower surface 46 which, as shown in FIG. 3 , abuts or rests against the trabecular meshwork 21 to stabilize the glaucoma stent 30 within the eye 10 . In modified embodiments, the seat 38 may efficaciously be shaped in other suitable manners, as required or desired, giving due consideration to the goals of stabilizing the glaucoma stent 30 within the eye 10 and/or of achieving one or more of the benefits and advantages as taught or suggested herein. For example, the seat 38 may be shaped in other polygonal or non-polygonal shapes and/or comprise one or more ridges which extend radially outwards, among other suitable retention devices.
[0100] In the illustrated embodiment of FIGS. 3-9 , and as best seen in the top view of FIG. 5 , the seat top surface 44 comprises fiducial marks or indicia 48 . These marks or indicia 48 facilitate and ensure proper orientation and alignment of the stent 30 when implanted in the eye 10 . The marks or indicia 48 may comprise visual differentiation means such as color contrast or be in the form of ribs, grooves, or the like. Alternatively, or in addition, the marks 48 may provide tactile sensory feedback to the surgeon by incorporating a radiopaque detectable or ultrasound imaginable substrate at about the mark 48 . Also, the seat 38 and/or the seat top surface 44 may be configured in predetermined shapes aligned with the blade 34 and/or longitudinal axis 36 to provide for proper orientation of the stent device 30 within the eye 10 . For example, the seat top surface 44 may be oval or ellipsoidal ( FIG. 10 ), rectangular ( FIG. 11 ), hexagonal ( FIG. 12 ), among other suitable shapes (e.g. FIG. 13 ).
[0101] In the illustrated embodiment of FIGS. 3-9 , and as indicated above, the seat bottom surface 46 abuts or rests against the trabecular meshwork 21 to stabilize and retain the glaucoma stent 30 within the eye 10 . For stabilization purposes, the seat bottom surface 46 may comprise a stubbed surface, a ribbed surface, a surface with pillars, a textured surface, or the like.
[0102] In the illustrated embodiment of FIGS. 3-9 , the snorkel shank 40 is generally cylindrical in shape. With the stent 30 implanted, as shown in FIG. 3 , the shank 40 is generally positioned in an incision or cavity 50 formed in the trabecular meshwork 21 by the self-trephining stent 30 . Advantageously, and as discussed further below, this single step of forming the cavity 50 by the stent 30 itself and placing the stent 30 in the desired position facilitates and expedites the overall surgical procedure. In modified embodiments, the snorkel shank 40 may efficaciously be shaped in other suitable manners, as required or desired. For example, the shank 40 may be in the shape of other polygonal or non-polygonal shapes, such as, oval, elliposoidal, and the like.
[0103] In the illustrated embodiment of FIGS. 3-9 , and as best seen in FIG. 3 , the shank 40 has an outer surface 52 in contact with the trabecular meshwork 21 surrounding the cavity 50 . For stabilization purposes, the shank outer surface 52 may comprise a stubbed surface, a ribbed surface, a surface with pillars, a textured surface, or the like.
[0104] In the illustrated embodiment of FIGS. 3-9 , the snorkel lumen 42 has an inlet port, opening or orifice 54 at the seat top surface 44 and an outlet port, opening or orifice 56 at the junction of the shank 40 and blade 34 . The lumen 42 is generally cylindrical in shape, that is, it has a generally circular cross-section, and its ports 54 , 56 are generally circular in shape. In modified embodiments, the lumen 42 and ports 54 , 56 may be efficaciously shaped in other manners, as required or desired, giving due consideration to the goals of providing sufficient aqueous outflow and/or of achieving one or more of the benefits and advantages as taught or suggested herein. For example, the lumen 42 and/or one or both ports 54 , 56 may be shaped in the form of ovals, ellipsoids, and the like, or the lumen 42 may have a tapered or stepped configuration.
[0105] Referring in particular to FIG. 3 , aqueous from the anterior chamber 20 flows into the lumen 42 through the inlet port 54 (as generally indicated by arrow 58 ) and out of the outlet port 56 and into Schlemm's canal 22 (as generally indicated by arrows 60 ) to lower and/or balance the intraocular pressure (IOP). In another embodiment, as discussed in further detail below, one or more of the outlet ports may be configured to face in the general direction of the stent longitudinal axis 36 . In modified embodiments, the snorkel 32 may comprise more than one lumen, as needed or desired, to facilitate multiple aqueous outflow transportation into Schlemm's canal 22 .
[0106] In the illustrated embodiment of FIGS. 3-9 , the blade longitudinal axis 36 and the snorkel longitudinal axis 43 are generally perpendicular to one another. Stated differently, the projections of the axes 36 , 43 on a common plane which is not perpendicular to either of the axes 36 , 43 intersect at 90°. The blade longitudinal axis 36 and the snorkel longitudinal axis 43 may intersect one another or may be offset from one another.
[0107] In the illustrated embodiment of FIGS. 3-9 , the main body portion or blade 34 is a generally curved elongated sheet- or plate-like structure with an upper curved surface 62 and a lower curved surface 64 which defines a trough or open face channel 66 . The perimeter of the blade 34 is generally defined by a curved proximal edge 68 proximate to the snorkel 32 , a curved distal edge 70 spaced from the proximal edge 68 by a pair of generally straight lateral edges 72 , 74 with the first lateral edge 72 extending beyond the second lateral edge 74 and intersecting with the distal edge 70 at a distal-most point 76 of the blade 34 proximate a blade cutting tip 78 .
[0108] In the illustrated embodiment of FIGS. 3-9 , and as shown in the enlarged view of FIG. 9 , the cutting tip 78 comprises a first cutting edge 80 on the distal edge 70 and a second cutting edge 82 on the lateral edge 72 . The cutting edges 80 , 82 preferably extend from the distal-most point 76 of the blade 34 and comprise at least a respective portion of the distal edge 70 and lateral edge 72 . The respective cutting edges 80 , 82 are formed at the sharp edges of respective beveled or tapered surfaces 84 , 86 . In one embodiment, the remainder of the distal edge 70 and lateral edge 72 are dull or rounded. In one embodiment, the tip 78 proximate to the distal-most end 76 is curved slightly inwards, as indicated generally by the arrow 88 in FIG. 5 and arrow 88 (pointed perpendicular and into the plane of the paper) in FIG. 9 , relative to the adjacent curvature of the blade 34 .
[0109] In modified embodiments, suitable cutting edges may be provided on selected portions of one or more selected blade edges 68 , 70 , 72 , 74 with efficacy, as needed or desired, giving due consideration to the goals of providing suitable cutting means on the stent 30 for effectively cutting through the trabecular meshwork 21 ( FIG. 3 ) and/or of achieving one or more of the benefits and advantages as taught or suggested herein.
[0110] Referring in particular to FIG. 9 , in one embodiment, the ratio between the lengths of the cutting edges 80 , 82 is about 2:1. In another embodiment, the ratio between the lengths of the cutting edges 80 , 82 is about 1:1. In yet another embodiment, the ratio between the lengths of the cutting edges 80 , 82 is about 1:2. In modified embodiments, the lengths of the cutting edges 80 , 82 may be efficaciously selected in other manners, as required or desired, giving due consideration to the goals of providing suitable cutting means on the stent 30 for effectively cutting through the trabecular meshwork 21 ( FIG. 3 ) and/or of achieving one or more of the benefits and advantages as taught or suggested herein.
[0111] Still referring in particular to FIG. 9 , in one embodiment, the ratio between the lengths of the cutting edges 80 , 82 is in the range from about 2:1 to about 1:2. In another embodiment, the ratio between the lengths of the cutting edges 80 , 82 is in the range from about 5:1 to about 1:5. In yet another embodiment, the ratio between the lengths of the cutting edges 80 , 82 is in the range from about 10:1 to about 1:10. In modified embodiments, the lengths of the cutting edges 80 , 82 may be efficaciously selected in other manners, as required or desired, giving due consideration to the goals of providing suitable cutting means on the stent 30 for effectively cutting through the trabecular meshwork 21 ( FIG. 3 ) and/or of achieving one or more of the benefits and advantages as taught or suggested herein.
[0112] As shown in the top view of FIG. 9 , the cutting edge 80 (and/or the distal end 70 ) and the cutting edge 82 (and/or the lateral edge 72 ) intersect at an angle θ. Stated differently, θ is the angle between the projections of the cutting edge 80 (and/or the distal end 70 ) and the cutting edge 82 (and/or the lateral edge 72 ) on a common plane which is not perpendicular to either of these edges.
[0113] Referring to in particular to FIG. 9 , in one embodiment, the angle θ is about 50°. In another embodiment, the angle θ is in the range from about 40° to about 60°. In yet another embodiment, the angle θ is in the range from about 30° to about 70°. In modified embodiments, the angle θ may be efficaciously selected in other manners, as required or desired, giving due consideration to the goals of providing suitable cutting means on the stent 30 for effectively cutting through the trabecular meshwork 21 ( FIG. 3 ) and/or of achieving one or more of the benefits and advantages as taught or suggested herein.
[0114] The stent 30 of the embodiments disclosed herein can be dimensioned in a wide variety of manners. Referring in particular to FIG. 3 , the depth of Schlemm's canal 22 is typically about less than 400 microns (μm). Accordingly, the stunt blade 34 is dimensioned so that the height of the blade 34 (referred to as H 41 in FIG. 4 ) is typically less than about 400 μm. The snorkel shank 40 is dimensioned so that it has a length (referred to as L 41 in FIG. 4 ) typically in the range from about 150 μm to about 400 μm which is roughly the typical range of the thickness of the trabecular meshwork 21 .
[0115] Of course, as the skilled artisan will appreciate, that with the stent 30 implanted, the blade 34 may rest at any suitable position within Schlemm's canal 22 . For example, the blade 34 may be adjacent to a front wall 90 of Schlemm's canal 22 (as shown in FIG. 3 ), or adjacent to a back wall 92 of Schlemm's canal 22 , or at some intermediate location therebetween, as needed or desired. Also, the snorkel shank 40 may extend into Schlemm's canal 22 . The length of the snorkel shank 40 and/or the dimensions of the blade 34 may be efficaciously adjusted to achieve the desired implant positioning.
[0116] The trabecular stenting device 30 ( FIGS. 3-9 ) of the exemplary embodiment may be manufactured or fabricated by a wide variety of techniques. These include, without limitation, by molding, thermo-forming, or other micro-machining techniques, among other suitable techniques.
[0117] The trabecular stenting device 30 preferably comprises a biocompatible material such that inflammation arising due to irritation between the outer surface of the device 30 and the surrounding tissue is minimized. Biocompatible materials which may be used for the device 30 preferably include, but are not limited to, titanium, titanium alloys, medical grade silicone, e.g., Silastic™, available from Dow Corning Corporation of Midland, Mich.; and polyurethane, e.g., Pellethane™, also available from Dow Corning Corporation.
[0118] In other embodiments, the stent device 30 may comprise other types of biocompatible material, such as, by way of example, polyvinyl alcohol, polyvinyl pyrolidone, collagen, heparinized collagen, polytetrafluoroethylene, expanded polytetrafluoroethylene, fluorinated polymer, fluorinated elastomer, flexible fused silica, polyolefin, polyester, polysilicon, and/or a mixture of the aforementioned biocompatible materials, and the like. In still other embodiments, composite biocompatible material may be used, wherein a surface material may be used in addition to one or more of the aforementioned materials. For example, such a surface material may include polytetrafluoroethylene (PTFE) (such as Teflon™), polyimide, hydrogel, heparin, therapeutic drugs (such as beta-adrenergic antagonists and other anti-glaucoma drugs, or antibiotics), and the like.
[0119] In an exemplary embodiment of the trabecular meshwork surgery, the patient is placed in the supine position, prepped, draped and anesthetized as necessary. In one embodiment, a small (less than about 1 mm) incision, which may be self sealing is made through the cornea 12 . The corneal incision can be made in a number of ways, for example, by using a micro-knife, among other tools.
[0120] An applicator or delivery apparatus is used to advance the glaucoma stent 30 through the corneal incision and to the trabecular meshwork 21 . Some embodiments of such a delivery apparatus are disclosed in copending U.S. application Ser. No. 10/101,548 (Inventors: Gregory T. Smedley, Irvine, Calif., Morteza Gharib, Pasadena, Calif., Hosheng Tu, Newport Beach, Calif.; Attorney Docket No.: GLAUKO.012A), filed Mar. 18, 2002, entitled APPLICATOR AND METHODS FOR PLACING A TRABECULAR SHUNT FOR GLAUCOMA TREATMENT, and U.S. Provisional Application No. 60/276,609, filed Mar. 16, 2001, entitled APPLICATOR AND METHODS FOR PLACING A TRABECULAR SHUNT FOR GLAUCOMA TREATMENT, the entire contents of each one of which are hereby incorporated by reference herein. Some embodiments of a delivery apparatus are also discussed in further detail later herein. Gonioscopic, microscopic, or endoscopic guidance may be used during the trabecular meshwork surgery.
[0121] With the device 30 held by the delivery apparatus, the blade 34 of the self-trephining glaucoma stent device 30 is used to cut and/or displace the material of the trabecular meshwork 21 . The snorkel shank 40 may also facilitate in removal of this material during implantation. The delivery apparatus is withdrawn once the device 30 has been implanted in the eye 10 . As shown in FIG. 3 , once proper implantation has been accomplished the snorkel seat 38 rests on a top surface 94 of the trabecular meshwork 21 , the snorkel shank 40 extends through the cavity 50 (created by the device 30 ) in the trabecular meshwork 21 , and the blade extends inside Schlemm's canal 22 .
[0122] Advantageously, the embodiments of the self-trephining stent device of the invention allow for a “one-step” procedure to make an incision in the trabecular meshwork and to subsequently implant the stent in the proper orientation and alignment within the eye to allow outflow of aqueous from the anterior chamber through the stent and into Schlemm's canal to lower and/or balance the intraocular pressure (IOP). Desirably, this provides for a faster, safer, and less expensive surgical procedure.
[0123] Many complications can arise in trabecular meshwork surgeries, wherein a knife is first used to create an incision in the trabecular meshwork, followed by removal of the knife and subsequent installation of the stent. For instance, the knife may cause some bleeding which clouds up the surgical site. This may require more effort and time to clean the surgical site prior to placement of the stent. Moreover, this may cause the intraocular pressure (IOP) to rise or to fall undesirably. Thus, undesirably, such a multiple step procedure may demand crisis management which slows down the surgery, makes it less safe, and more expensive.
[0124] FIG. 14 is a simplified partial view of an eye 10 illustrating the implantation of a self-trephining glaucoma stent device 30 a having features and advantages in accordance with one embodiment. The stent 30 a is generally similar to the stent 30 of FIGS. 3-9 except that its snorkel 32 a comprises a longer shank 40 a which extends into Schlemm's canal 22 and a lumen 42 a which bifurcates into two output channels 45 a.
[0125] In the illustrated embodiment of FIG. 14 , the shank 40 a terminates at the blade 34 . Aqueous flows from the anterior chamber 20 into the lumen 42 a through an inlet port 54 a (as generally indicated by arrow 58 a ). Aqueous then flows through the output channels 45 a and out of respective outlet ports 56 a and into Schlemm's canal 22 (as generally indicated by arrows 60 a ). The outlet channels 45 a extend radially outwards in generally opposed directions and the outlet ports 56 a are configured to face in the general direction of the stent longitudinal axis 36 so that they open into Schlemm's canal 22 and are in proper orientation to allow aqueous outflow into Schlemm's canal 22 for lowering and/or balancing the intraocular pressure (IOP). As indicated above, fiducial marks or indicia and/or predetermined shapes of the snorkel seat 38 allow for proper orientation of the blade 34 and also the output channels 45 a and respective ports 56 a within Schlemm's canal.
[0126] In the illustrated embodiment of FIG. 14 , two outflow channels 45 a are provided. In another embodiment, only one outflow channel 45 a is provided. In yet another embodiment, more than two outflow channels 45 a are provided. In modified embodiments, the lumen 42 a may extend all the way through to the blade 34 and provide an outlet port as discussed above with reference to the embodiment of FIGS. 3-9 .
[0127] FIG. 15 is a simplified partial view of an eye 10 illustrating the implantation of a self-trephining glaucoma stent device 30 b having features and advantages in accordance with one embodiment. The stent 30 b is generally similar to the stent 30 of FIGS. 3-9 except that its snorkel 32 b comprises a longer shank 40 b which extends into Schlemm's canal 22 and a lumen 42 b which bifurcates into two output channels 45 b.
[0128] In the illustrated embodiment of FIG. 15 , the shank 40 b extends through the blade 34 . Aqueous flows from the anterior chamber 20 into the lumen 42 b through an inlet port 54 b (as generally indicated by arrow 58 b ). Aqueous then flows through the output channels 45 b and out of respective outlet ports 56 b and into Schlemm's canal 22 (as generally indicated by arrows 60 b ). The outlet channels 45 b extend radially outwards in generally opposed directions and the outlet ports 56 b are configured to face in the general direction of the stent longitudinal axis 36 so that they open into Schlemm's canal 22 and are in proper orientation to allow aqueous outflow into Schlemm's canal 22 for lowering and/or balancing the intraocular pressure (IOP). As indicated above, fiducial marks or indicia and/or predetermined shapes of the snorkel seat 38 allow for proper orientation of the blade 34 and also the output channels 45 b and respective ports 56 b within Schlemm's canal.
[0129] In the illustrated embodiment of FIG. 15 , two outflow channels 45 b are provided. In another embodiment, only one outflow channel 45 b is provided. In yet another embodiment, more than two outflow channels 45 b are provided. In modified embodiments, the lumen 42 b may extend all the way through to the blade 34 and provide an outlet port as discussed above with reference to the embodiment of FIGS. 3-9 .
[0130] FIGS. 16-20 show different views of a self-trephining glaucoma stent device 30 c having features and advantages in accordance with one embodiment. The stent 30 c is generally similar to the stent 30 of FIGS. 3-9 except that it has a modified blade configuration. The stent 30 c comprises a blade 34 c which is a generally curved elongated sheet- or plate-like structure with an upper curved surface 62 c and a lower curved surface 64 c which defines a trough or open face channel 66 c . The perimeter of the blade 34 c is generally defined by a curved proximal edge 68 c proximate to the snorkel 32 , a curved distal edge 70 c spaced from the proximal edge 68 c by a pair of generally straight lateral edges 72 c , 74 c which are generally parallel to one another and have about the same length.
[0131] In the illustrated embodiment of FIGS. 16-20 , the blade 34 c comprises a cutting tip 78 c . The cutting tip 78 c preferably includes cutting edges formed on selected portions of the distal edge 70 c and adjacent portions of the lateral edges 72 c , 74 c for cutting through the trabecular meshwork for placement of the snorkel 32 . The cutting edges are sharp edges of beveled or tapered surfaces as discussed above in reference to FIG. 9 . The embodiment of FIGS. 16-20 may be efficaciously modified to incorporate the snorkel configuration of the embodiments of FIGS. 14 and 15 .
[0132] FIGS. 21-25 show different views of a self-trephining glaucoma stent device 30 d having features and advantages in accordance with one embodiment. The stent 30 d is generally similar to the stent 30 of FIGS. 3-9 except that it has a modified blade configuration. The stent 30 d comprises a blade 34 d which is a generally curved elongated sheet- or plate-like structure with an upper curved surface 62 d and a lower curved surface 64 d which defines a trough or open face channel 66 d . The perimeter of the blade 34 d is generally defined by a curved proximal edge 68 d proximate to the snorkel 32 , a pair of inwardly converging curved distal edges 70 d ′, 70 d ″ spaced from the proximal edge 68 d by a pair of generally straight respective lateral edges 72 d , 74 d which are generally parallel to one another and have about the same length. The distal edges 70 d ′, 70 d ″ intersect at a distal-most point 76 d of the blade 34 d proximate a blade cutting tip 78 d.
[0133] In the illustrated embodiment of FIGS. 21-25 , the cutting tip 78 d preferably includes cutting edges formed on the distal edges 70 d ′, 70 d ″ and extending from the distal-most point 76 d of the blade 34 d . In one embodiment, the cutting edges extend along only a portion of respective distal edges 70 d ′, 70 d ″. In another embodiment, the cutting edges extend along substantially the entire length of respective distal edges 70 d ′, 70 d ″. In yet another embodiment, at least portions of the lateral edges 72 d , 74 d proximate to respective distal edges 70 d ′, 70 d ″ have cutting edges. In a further embodiment, the tip 78 d proximate to the distal-most end 76 d is curved slightly inwards, as indicated generally by the arrow 88 d in FIG. 21 and arrow 88 d (pointed perpendicular and into the plane of the paper) in FIG. 22 , relative to the adjacent curvature of the blade 34 d.
[0134] In the embodiment of FIGS. 21-25 , the cutting edges are sharp edges of beveled or tapered surfaces as discussed above in reference to FIG. 9 . The embodiment of FIGS. 21-25 may be efficaciously modified to incorporate the snorkel configuration of the embodiments of FIGS. 14 and 15 .
[0135] FIGS. 26-28 show different views of a self-trephining glaucoma stent device 30 e having features and advantages in accordance with one embodiment. The stent device 30 e generally comprises a snorkel 32 e mechanically connected to or in mechanical communication with a blade or cutting tip 34 e . The snorkel 32 e has a seat, head or cap portion 38 e mechanically connected to or in mechanical communication with a shank 40 e , as discussed above. The shank 40 e has a distal end or base 47 e . The snorkel 32 e further has a lumen 42 e which bifurcates into a pair of outlet channels 45 e , as discussed above in connection with FIGS. 14 and 15 . Other lumen and inlet and outlet port configurations as taught or suggested herein may also be efficaciously used, as needed or desired.
[0136] In the illustrated embodiment of FIGS. 26-28 , the blade 34 e extends downwardly and outwardly from the shank distal end 47 e . The blade 34 e is angled relative to a generally longitudinal axis 43 e of the snorkel 32 e , as best seen in FIGS. 27 and 28 . The blade 34 e has a distal-most point 76 e . The blade or cutting tip 34 e has a pair of side edges 70 e ′, 70 e ″, including cutting edges, terminating at the distal-most point 76 e , as best seen in FIG. 26 . In one embodiment, the cutting edges are sharp edges of beveled or tapered surfaces as discussed above in reference to FIG. 9 .
[0137] Referring to FIGS. 26-28 , in one embodiment, the blade 34 e includes cutting edges formed on the edges 70 e ′, 70 e ″ and extending from the distal-most point 76 e of the blade 34 d . In one embodiment, the cutting edges extend along only a portion of respective distal edges 70 e ′, 70 e ″. In another embodiment, the cutting edges extend along substantially the entire length of respective distal edges 70 e ′, 70 e ″. In yet another embodiment, the blade or cutting tip 34 e comprises a bent tip of needle, for example, a 30 gauge needle.
[0138] In general, any of the blade configurations disclosed herein may be used in conjunction with any of the snorkel configurations disclosed herein or incorporated by reference herein to provide a self-trephining glaucoma stent device for making an incision in the trabecular meshwork for receiving the corresponding snorkel to provide a pathway for aqueous outflow from the eye anterior chamber to Schlemm's canal, thereby effectively lowering and/or balancing the intraocular pressure (IOP). The self-trephining ability of the device, advantageously, allows for a “one-step” procedure in which the incision and placement of the snorkel are accomplished by a single device and operation. In any of the embodiments, fiducial markings or indicia, and/or preselected configuration of the snorkel seat, and/or positioning of the stent device in a preloaded applicator may be used for proper orientation and alignment of the device during implantation.
Delivery Apparatus
[0139] In many cases, a surgeon works from a temporal incision when performing cataract or goniometry surgery. FIG. 29 illustrates a temporal implant procedure, wherein a delivery apparatus or “applicator” 100 having a curved tip 102 is used to deliver a stent 30 to a temporal side 27 of the eye 10 . An incision 28 is made in the cornea 10 , as discussed above. The apparatus 100 is then used to introduce the stent 30 through the incision 28 and implant it within the eye 10 .
[0140] Still referring in particular to FIG. 29 , in one embodiment, a similarly curved instrument would be used to make the incision through the trabecular meshwork 21 . In other embodiments, a self-trephining stent device 30 may be used to make this incision through the trabecular meshwork 21 , as discussed above. The temporal implantation procedure illustrated in FIG. 29 may be employed with the any of the various stent embodiments taught or suggested herein.
[0141] FIG. 30 illustrates one embodiment of an apparatus comprising an articulating stent applicator or retrieval device 100 a . In this embodiment, a proximal arm 106 is attached to a distal arm 108 at a joint 112 . This joint 112 is movable such that an angle formed between the proximal arm 106 and the distal arm 108 can change. One or more claws 114 can extend from the distal arm 108 , in the case of a stent retrieval device. Similarly, this articulation mechanism may be used for the trabecular stent applicator, and thus the articulating applicator or retrieval device 100 a may be either an applicator for the trabecular stent, a retrieval device, or both, in various embodiments. The embodiment of FIG. 30 may be employed with the any of the various stent embodiments taught or suggested herein.
[0142] FIG. 31 shows another illustrative method for placing any of the various stent embodiments taught or suggested herein at the implant site within the eye 10 . A delivery apparatus 100 b generally comprises a syringe portion 116 and a cannula portion 118 . The distal section of the cannula 118 has at least one irrigating hole 120 and a distal space 122 for holding the stent device 30 . The proximal end 124 of the lumen of the distal space 122 is sealed from the remaining lumen of the cannula portion 118 . The delivery apparatus of FIG. 30 may be employed with the any of the various stent embodiments taught or suggested herein.
[0143] In one aspect of the invention, a delivery apparatus (or “applicator”) is used for placing a trabecular stent through a trabecular meshwork of an eye. Certain embodiments of such a delivery apparatus are disclosed in copending U.S. application Ser. No. 10/101,548 (Inventors: Gregory T. Smedley, Irvine, Calif., Morteza Gharib, Pasadena, Calif., Hosheng Tu, Newport Beach, Calif.; Attorney Docket No.: GLAUKO.012A), filed Mar. 18, 2002, entitled APPLICATOR AND METHODS FOR PLACING A TRABECULAR SHUNT FOR GLAUCOMA TREATMENT, and U.S. Provisional Application No. 60/276,609, filed Mar. 16, 2001, entitled APPLICATOR AND METHODS FOR PLACING A TRABECULAR SHUNT FOR GLAUCOMA TREATMENT, the entire contents of each one of which are hereby incorporated by reference herein.
[0144] The stent has an inlet section and an outlet section. The delivery apparatus includes a handpiece, an elongate tip, a holder and an actuator. The handpiece has a distal end and a proximal end. The elongate tip is connected to the distal end of the handpiece. The elongate tip has a distal portion and is configured to be placed through a corneal incision and into an anterior chamber of the eye. The holder is attached to the distal portion of the elongate tip. The holder is configured to hold and release the inlet section of the trabecular stent. The actuator is on the handpiece and actuates the holder to release the inlet section of the trabecular stent from the holder. When the trabecular stent is deployed from the delivery apparatus into the eye, the outlet section is positioned in substantially opposite directions inside Schlemm's canal. In one embodiment, a deployment mechanism within the delivery apparatus includes a push-pull type plunger.
[0145] In some embodiments, the holder comprises a clamp. In some embodiments, the apparatus further comprises a spring within the handpiece that is configured to be loaded when the stent is being held by the holder, the spring being at least partially unloaded upon actuating the actuator, allowing for release of the stent from the holder.
[0146] In various embodiments, the clamp comprises a plurality of claws configured to exert a clamping force onto the inlet section of the stent. The holder may also comprise a plurality of flanges.
[0147] In some embodiments, the distal portion of the elongate tip is made of a flexible material. This can be a flexible wire. The distal portion can have a deflection range, preferably of about 45 degrees from the long axis of the handpiece.
[0148] The delivery apparatus can further comprise an irrigation port in the elongate tip.
[0149] Some aspects include a method of placing a trabecular stent through a trabecular meshwork of an eye, the stent having an inlet section and an outlet section, including advancing a delivery apparatus holding the trabecular stent through an anterior chamber of the eye and into the trabecular meshwork, placing part of the stent through the trabecular meshwork and into a Schlemm's canal of the eye; and releasing the stent from the delivery apparatus.
[0150] In various embodiments, the method includes using a delivery apparatus that comprises a handpiece having a distal end and a proximal end; an elongate tip connected to the distal end of the handpiece, the elongate tip having a distal portion and being configured to be placed through a corneal incision and into an anterior chamber of the eye; a holder attached to the distal portion of the elongate tip, the holder configured to hold and release the inlet section of the trabecular stent; and an actuator on the handpiece that actuates the holder to release the inlet section of the trabecular stent from the holder.
[0151] In one aspect, the trabecular stent is removably attached to a delivery apparatus (also known as “applicator”). When the trabecular stent is deployed from the delivery apparatus into the eye, the outlet section is positioned in substantially opposite directions inside Schlemm's canal. In one embodiment, a deployment mechanism within the delivery apparatus includes a push-pull type plunger. In some embodiments, the delivery applicator may be a guidewire, an expandable basket, an inflatable balloon, or the like.
Other Embodiments
Screw/Barb Anchored Stent
[0152] FIGS. 32 and 33 illustrate a glaucoma stent device 30 f having features and advantages in accordance with one embodiment. This embodiment of the trabecular stent 30 f includes a barbed or threaded screw-like extension or pin 126 with barbs 128 for anchoring. The barbed pin 126 extends from a distal or base portion 130 of the stent 30 f.
[0153] In use, the stent 30 f ( FIG. 32 ) is advanced through the trabecular meshwork 21 and across Schlemm's canal 22 . The barbed (or threaded) extension 126 penetrates into the back wall 92 of Schlemm's canal 22 up to the shoulder or base 130 that then rests on the back wall 92 of the canal 22 . The combination of a shoulder 130 and a barbed pin 126 of a particular length limits the penetration depth of the barbed pin 126 to a predetermined or preselected distance. In one embodiment, the length of the pin 126 is about 0.5 mm or less. Advantageously, this barbed configuration provides a secure anchoring of the stent 30 f As discussed above, correct orientation of the stent 30 f is ensured by appropriate fiducial marks, indicia or the like and by positioning of the stent in a preloaded applicator.
[0154] Referring to FIG. 32 , the aqueous flows from the anterior chamber 20 , through the lumen 42 f , then out through two side-ports 56 f to be directed in both directions along Schlemm's canal 22 . Alternatively, flow could be directed in only one direction through a single side-port 56 f In other embodiments, more then two outlet ports 56 f , for example, six to eight ports (like a pin wheel configuration), may be efficaciously used, as needed or desired.
[0155] Still referring to FIG. 32 , in one embodiment, the stent 30 f is inserted through a previously made incision in the trabecular meshwork 21 . In other embodiments, the stent 30 f may be combined with any of the blade configurations taught or suggested herein to provide self-trephining capability. In these cases, the incision through the trabecular meshwork 21 is made by the self-trephining stent device which has a blade at its base or proximate to the base.
Deeply Threaded Stent:
[0156] FIG. 34 illustrates a glaucoma stent device 30 g having features and advantages in accordance with one embodiment. The stent 30 g has a head or seat 38 g and a shank or main body portion 40 g with a base or distal end 132 . This embodiment of the trabecular stent 30 g includes a deep thread 134 (with threads 136 ) on the main body 40 g of the stent 30 g below the head 38 g . The threads may or may not extend all the way to the base 132 .
[0157] In use, the stent 30 g ( FIG. 34 ) is advanced through the meshwork 21 through a rotating motion, as with a conventional screw. Advantageously, the deep threads 136 provide retention and stabilization of the stent 30 g in the trabecular meshwork 21 .
[0158] Referring to FIG. 34 , the aqueous flows from the anterior chamber 20 , through the lumen 42 g , then out through two side-ports 56 g to be directed in both directions along Schlemm's canal 22 . Alternatively, flow could be directed in only one direction through a single side-port 56 g . In other embodiments, more then two outlet ports 56 g may be efficaciously used, as needed or desired.
[0159] One suitable applicator or delivery apparatus for this stent 30 g ( FIG. 34 ) includes a preset rotation, for example, via a wound torsion spring or the like. The rotation is initiated by a release trigger on the applicator. A final twist of the applicator by the surgeon and observation of suitable fiducial marks, indicia or the like ensure proper alignment of the side ports 56 g with Schlemm's canal 22 .
[0160] Referring to FIG. 34 , in one embodiment, the stent 30 g is inserted through a previously made incision in the trabecular meshwork 21 . In other embodiments, the stent 30 g may be combined with any of the blade configurations taught or suggested herein to provide self-trephining capability. In these cases, the incision through the trabecular meshwork 21 is made by the self-trephining stent device which has a blade at its base or proximate to the base.
Rivet Style Stent:
[0161] FIG. 35 illustrates a glaucoma stent device 30 h having features and advantages in accordance with one embodiment. The stent has a base or distal end 138 . This embodiment of the trabecular stent 30 h has a pair of flexible ribs 140 . In the unused state, the ribs are initially generally straight (that is, extend in the general direction of arrow 142 ).
[0162] Referring to FIG. 35 , upon insertion of the stent 30 h through the trabecular meshwork 21 , the ends 144 of respective ribs 140 of the stent 30 h come to rest on the back wall 92 of Schlemm's canal 22 . Further advancement of the stent 30 h causes the ribs 140 to deform to the bent shape as shown in the drawing of FIG. 35 . The ribs 140 are designed to first buckle near the base 138 of the stent 30 h . Then the buckling point moves up the ribs 140 as the shank part 40 h of the stent 30 h is further advanced through the trabecular meshwork 21 .
[0163] The lumen 42 h ( FIG. 35 ) in the stent 30 h is a simple straight hole. The aqueous flows from the anterior chamber 20 , through the lumen 42 h , then out around the ribs 140 to the collector channels further along Schlemm's canal 22 in either direction.
[0164] Referring to FIG. 35 , in one embodiment, the stent 30 h is inserted through a previously made incision in the trabecular meshwork 21 . In other embodiments, the stent 30 h may be combined with any of the blade configurations taught or suggested herein to provide self-trephining capability. In these cases, the incision through the trabecular meshwork 21 is made by the self-trephining stent device which has a blade at its base or proximate to the base.
Grommet Style Stent:
[0165] FIG. 36 illustrates a glaucoma stent device 30 i having features and advantages in accordance with one embodiment. This embodiment of the trabecular stent 30 i includes a head or seat 38 i , a tapered base portion 146 and an intermediate narrower waist portion or shank 40 i.
[0166] In use, the stent 30 i ( FIG. 36 ) is advanced through the trabecular meshwork 21 and the base 146 is pushed into Schlemm's canal 22 . The stent 30 i is pushed slightly further, if necessary, until the meshwork 21 stretched by the tapered base 146 relaxes back and then contracts to engage the smaller diameter portion waist 40 i of the stent 30 i . Advantageously, the combination of the larger diameter head or seat 38 i and base 146 of the stent 30 i constrains undesirable stent movement. As discussed above, correct orientation of the stent 30 i is ensured by appropriate fiducial marks, indicia or the like and by positioning of the stent in a preloaded applicator.
[0167] Referring to FIG. 36 , the aqueous flows from the anterior chamber 20 , through the lumen 42 i , then out through two side-ports 56 i to be directed in both directions along Schlemm's canal 22 . Alternatively, flow could be directed in only one direction through a single side-port 56 i . In other embodiments, more then two outlet ports 56 i may be efficaciously used, as needed or desired.
[0168] Still referring to FIG. 36 , in one embodiment, the stent 30 i is inserted through a previously made incision in the trabecular meshwork 21 . In other embodiments, the stent 30 i may be combined with any of the blade configurations taught or suggested herein to provide self-trephining capability. In these cases, the incision through the trabecular meshwork 21 is made by the self-trephining stent device which has a blade at its base or proximate to the base.
Biointeractive Stent:
[0169] FIG. 37 illustrates a glaucoma stent device 30 j having features and advantages in accordance with one embodiment. This embodiment of the trabecular stent 30 j utilizes a region of biointeractive material 148 that provides a site for the trabecular meshwork 21 to firmly grip the stent 30 j by ingrowth of the tissue into the biointeractive material 148 . As shown in FIG. 37 , preferably the biointeractive layer 148 is applied to those surfaces of the stent 30 j which would abut against or come in contact with the trabecular meshwork 21 .
[0170] In one embodiment, the biointeractive layer 148 ( FIG. 37 ) may be a region of enhanced porosity with a growth promoting chemical. In one embodiment, a type of bio-glue 150 that dissolves over time is used to hold the stent secure during the time between insertion and sufficient ingrowth for stabilization. As discussed above, correct orientation of the stent 30 j is ensured by appropriate fiducial marks, indicia or the like and by positioning of the stent in a preloaded applicator.
[0171] Referring to FIG. 37 , the aqueous flows from the anterior chamber 20 , through the lumen 42 j , then out through two side-ports 56 j to be directed in both directions along Schlemm's canal 22 . Alternatively, flow could be directed in only one direction through a single side-port 56 j . In other embodiments, more then two outlet ports 56 j may be efficaciously used, as needed or desired.
[0172] Still referring to FIG. 37 , in one embodiment, the stent 30 j is inserted through a previously made incision in the trabecular meshwork 21 . In other embodiments, the stent 30 j may be combined with any of the blade configurations taught or suggested herein to provide self-trephining capability. In these cases, the incision through the trabecular meshwork 21 is made by the self-trephining stent device which has a blade at its base or proximate to the base.
Glued or Welded Stent:
[0173] FIG. 38 illustrates a glaucoma stent device 30 k having features and advantages in accordance with one embodiment. This embodiment of the trabecular stent 30 k is secured in place by using a permanent (non-dissolving) bio-glue 152 or a “welding” process (e.g. heat) to form a weld 152 . The stent 30 k has a head or seat 38 k and a lower surface 46 k.
[0174] The stent 30 k is advanced through the trabecular meshwork 21 until the head or seat 38 k comes to rest on the trabecular meshwork 21 , that is, the head lower surface 46 k abuts against the trabecular meshwork 21 , and the glue or weld 152 is applied or formed therebetween, as shown in FIG. 38 . As discussed above, correct orientation of the stent 30 k is ensured by appropriate fiducial marks, indicia or the like and by positioning of the stent in a preloaded applicator.
[0175] Referring to FIG. 38 , the aqueous flows from the anterior chamber 20 , through the lumen 42 k , then out through two side-ports 56 k to be directed in both directions along Schlemm's canal 22 . Alternatively, flow could be directed in only one direction through a single side-port 56 k . In other embodiments, more then two outlet ports 56 k may be efficaciously used, as needed or desired.
[0176] Still referring to FIG. 38 , in one embodiment, the stent 30 k is inserted through a previously made incision in the trabecular meshwork 21 . In other embodiments, the stent 30 k may be combined with any of the blade configurations taught or suggested herein to provide self-trephining capability. In these cases, the incision through the trabecular meshwork 21 is made by the self-trephining stent device which has a blade at its base or proximate to the base.
Hydrophilic Latching Stent:
[0177] FIG. 39 illustrates a glaucoma stent device 30 m having features and advantages in accordance with one embodiment. This embodiment of the trabecular stent 30 m is fabricated from a hydrophilic material that expands with absorption of water. Desirably, this would enable the device 30 m to be inserted through a smaller incision in the trabecular meshwork 21 . The subsequent expansion (illustrated by the smaller arrows 154 ) of the stent 30 m would advantageously enable it to latch in place in the trabecular meshwork 21 . As discussed above, correct orientation of the stent 30 m is ensured by appropriate fiducial marks, indicia or the like and by positioning of the stent in a preloaded applicator.
[0178] Referring to FIG. 39 , the aqueous flows from the anterior chamber 20 , through the lumen 42 m , then out through two side-ports 56 m to be directed in both directions along Schlemm's canal 22 . Alternatively, flow could be directed in only one direction through a single side-port 56 m . In other embodiments, more then two outlet ports 56 m may be efficaciously used, as needed or desired.
[0179] Still referring to FIG. 39 , in one embodiment, the stent 30 m is inserted through a previously made incision in the trabecular meshwork 21 . In other embodiments, the stent 30 m may be combined with any of the blade configurations taught or suggested herein to provide self-trephining capability. In these cases, the incision through the trabecular meshwork 21 is made by the self-trephining stent device which has a blade at its base or proximate to the base.
Photodynamic Stent:
[0180] FIG. 40 illustrates a glaucoma stent device 30 n having features and advantages in accordance with one embodiment. This embodiment of the trabecular stent 30 n is fabricated from a photodynamic material that expands on exposure to light.
[0181] It is commonly known that there is a diurnal variation in the aqueous humor production by the eye—it is higher during the day than it is at night. The lumen 42 n of the stent 30 n responds to light entering the cornea during the day by expanding and allowing higher flow of aqueous through the lumen 42 n and into Schlemm's canal 22 . This expansion is generally indicated by the smaller arrows 156 ( FIG. 40 ) which show the lumen 42 n (and ports) expanding or opening in response to light stimulus. (The light or radiation energy E is generally given by E=hν, where h is Planck's constant and ν is the frequency of the light provided.) At night, in darkness, the lumen diameter decreases and reduces the flow allowed through the lumen 42 n . In one embodiment, an excitation wavelength that is different from that commonly encountered is provided on an as-needed basis to provide higher flow of aqueous to Schlemm's canal 22 .
[0182] This photodynamic implementation is shown in FIG. 40 for the self-latching style of stent 30 n , but can be efficaciously used with any of the other stent embodiments, as needed or desired. As discussed above, correct orientation of the stent 30 n is ensured by appropriate fiducial marks, indicia or the like and by positioning of the stent in a preloaded applicator.
[0183] Referring to FIG. 40 , the aqueous flows from the anterior chamber 20 , through the lumen 42 n , then out through two side-ports 56 n to be directed in both directions along Schlemm's canal 22 . Alternatively, flow could be directed in only one direction through a single side-port 56 n . In other embodiments, more then two outlet ports 56 n may be efficaciously used, as needed or desired.
[0184] Still referring to FIG. 40 , in one embodiment, the stent 30 n is inserted through a previously made incision in the trabecular meshwork 21 . In other embodiments, the stent 30 n may be combined with any of the blade configurations taught or suggested herein to provide self-trephining capability. In these cases, the incision through the trabecular meshwork 21 is made by the self-trephining stent device which has a blade at its base or proximate to the base.
Collector Channel Alignment Stent:
[0185] FIG. 41 illustrates a glaucoma stent device 30 p having features and advantages in accordance with one embodiment. This figure depicts an embodiment of a stent 30 p that directs aqueous from the anterior chamber 20 directly into a collector channel 29 which empties into aqueous veins. The stent 30 p has a base or distal end 160 .
[0186] In the illustrated embodiment of FIG. 41 , a removable alignment pin 158 is utilized to align the stent lumen 42 p with the collector channel 29 . In use, the pin 158 extends through the stent lumen 42 p and protrudes through the base 160 and extends into the collector channel 29 to center and/or align the stent 30 p over the collector channel 29 . The stent 30 p is then pressed firmly against the back wall 92 of Schlemm's canal 22 . A permanent bio-glue 162 is used between the stent base and the back wall 92 of Schlemm's canal 22 to seat and securely hold the stent 30 p in place. Once positioned, the pin 158 is withdrawn from the lumen 42 p to allow the aqueous to flow directly from the anterior chamber 20 into the collector duct 29 . The collector ducts are nominally 20 to 100 micrometers (μm) in diameter and are visualized with a suitable microscopy method (such as ultrasound biomicroscopy (UBM)) or laser imaging to provide guidance for placement of the stent 30 p . Referring to FIG. 41 , in one embodiment, the stent 30 p is inserted through a previously made incision in the trabecular meshwork 21 . In other embodiments, the stent 30 p may be combined with any of the blade configurations taught or suggested herein to provide self-trephining capability. In these cases, the incision through the trabecular meshwork 21 is made by the self-trephining stent device which has a blade at its base or proximate to the base.
Barbed Stent (Anterior Chamber to Collector Channel):
[0187] FIG. 42 illustrates a glaucoma stent device 30 q having features and advantages in accordance with one embodiment. This figure depicts an embodiment of a stent 30 q that directs aqueous from the anterior chamber 20 directly into a collector channel 29 which empties into aqueous veins. The stent 30 q has a base or distal end 166 and the channel 29 has wall(s) 164 .
[0188] In the illustrated embodiment of FIG. 42 , a barbed, small-diameter extension or pin 168 on the stent base 166 is guided into the collector channel 29 and anchors on the wall(s) 164 of the channel 29 . The pin 168 has barbs 170 which advantageously provide anchoring of the stent 30 q . The collector ducts 29 are nominally 20 to 100 micrometers (μm) in diameter and are visualized with a suitable microscopy method (such as ultrasound biomicroscopy (UBM)) or laser imaging to provide guidance for placement of the stent.
[0189] Referring to FIG. 42 , in one embodiment, the stent 30 q is inserted through a previously made incision in the trabecular meshwork 21 . In other embodiments, the stent 30 q may be combined with any of the blade configurations taught or suggested herein to provide self-trephining capability. In these cases, the incision through the trabecular meshwork 21 is made by the self-trephining stent device which has a blade at its base or proximate to the base.
Valved Tube Stent (Anterior Chamber to Choroid):
[0190] FIG. 43 illustrates a valved tube stent device 30 r having features and advantages in accordance with one embodiment. This is an embodiment of a stent 30 r that provides a channel for flow between the anterior chamber 20 and the highly vascular choroid 17 . Clinically, the choroid 17 can be at pressures lower than those desired for the eye 10 . Therefore, this stent 30 r includes a valve with an opening pressure equal to the desired pressure difference between the choroid 17 and the anterior chamber 10 or a constriction that provide the desired pressure drop.
Osmotic Membrane (Anterior Chamber to Choroid):
[0191] FIG. 44 illustrates an osmotic membrane device 30 s having features and advantages in accordance with one embodiment. This embodiment provides a channel for flow between the anterior chamber 20 and the highly vascular choroid 17 . The osmotic membrane 30 s is used to replace a portion of the endothelial layer of the choroid 17 . Since the choroid 17 is highly vascular with blood vessels, the concentration of water on the choroid side is lower than in the anterior chamber 20 of the eye 10 . Therefore, the osmotic gradient drives water from the anterior chamber 20 into the choroid 17 .
[0192] Clinically, the choroid 17 ( FIG. 44 ) can be at pressures lower than those desired for the eye 10 . Therefore, desirably, both osmotic pressure and the physical pressure gradient are in favor of flow into the choroid 17 . Flow control is provided by proper sizing of the area of the membrane,—the larger the membrane area is the larger the flow rate will be. This advantageously enables tailoring to tune the flow to the desired physiological rates.
Ab Externo Insertion of Stent via Small Puncture:
[0193] FIG. 45 illustrates the implantation of a stent 30 t using an ab externo procedure having features and advantages in accordance with one embodiment. In the ab externo procedure of FIG. 45 , the stent 30 t is inserted into Schlemm's canal 21 with the aid of an applicator or delivery apparatus 100 c that creates a small puncture into the eye 10 from outside.
[0194] Referring to FIG. 45 , the stent 30 t is housed in the applicator 100 c , and pushed out of the applicator 100 c once the applicator tip is in position within the trabecular meshwork 21 . Since the tissue surrounding the trabecular meshwork 21 is optically opaque, an imaging technique, such as ultrasound biomicroscopy (UBM) or a laser imaging technique, is utilized. The imaging provides guidance for the insertion of the applicator tip and the deployment of the stent 30 t . This technique can be used with a large variety of stent embodiments with slight modifications since the trabecular meshwork 21 is punctured from the scleral side rather than the anterior chamber side in the ab externo insertion.
[0195] FIG. 46 a glaucoma stent device 30 u having features and advantages in accordance with a modified embodiment. This grommet-style stent 30 u for ab externo insertion is a modification of the embodiment of FIG. 36 . In the embodiment of FIG. 46 , the upper part or head 38 u is tapered while the lower part or base 172 is flat, as opposed to the embodiment of FIG. 36 . The stent 30 u is inserted from the outside of the eye 10 through a puncture in the sclera. Many of the other embodiments of stents taught or suggested herein can be modified for similar implantation.
[0196] This ultra microscopic device 30 u ( FIG. 46 ) can be used with (1) a targeting Lasik-type laser, or with (2) contact on eyes or with (3) combined ultrasound microscope or (4) other device insertor handpiece.
Targeted Drug Delivery to the Trabecular Meshwork:
[0197] FIG. 47 illustrates a targeted drug delivery implant 30 v having features and advantages in accordance with one embodiment. This drawing is a depiction of a targeted drug delivery concept. The slow release implant 30 v is implanted within the trabecular meshwork 21 .
[0198] A drug that is designed to target the trabecular meshwork 21 to increase its porosity, or improve the active transport across the endothelial layer of Schlemm's canal 22 can be stored in this small implant 30 v ( FIG. 47 ). Advantageously, slow release of the drug promotes the desired physiology at minimal dosage levels since the drug is released into the very structure that it is designed to modify.
[0199] While the components and techniques of the invention have been described with a certain degree of particularity, it is manifest that many changes may be made in the specific designs, constructions and methodology herein above described without departing from the spirit and scope of this disclosure. It should be understood that the invention is not limited to the embodiments set forth herein for purposes of exemplification, but is to be defined only by a fair reading of the appended claims, including the full range of equivalency to which each element thereof is entitled.
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Implants and methods for treating ocular disorders are disclosed. One implant has a tubular member, with inlet and outlet ends, and a cutting member connected thereto. The tubular member is configured to extend through eye tissue such that the inlet and outlet ends reside respectively in an anterior chamber and a physiologic outflow pathway of the eye. Desirably, the cutting member is configured to make an incision in the eye tissue for receiving at least a portion of the tubular member. One method involves introducing an implant, with proximal and distal ends, into the anterior chamber and penetrating eye tissue using an implant distal portion. The implant is advanced from the anterior chamber into the penetrated eye tissue to locate the distal and proximal ends respectively in the physiologic outflow pathway and the anterior chamber. Aqueous humor is conducted between the proximal and distal ends.
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CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of co-pending U.S. application Ser. No. 11/362,297, filed Feb. 24, 2006 and entitled “Repair Swatch for Hail Damaged Asphalt Roofing,” hereby incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates generally to the repair of damaged roofing, particularly roofing referred to as steep slope, and more specifically, to a repair swatch for the protection of part of a roofing that has been damaged, such as by extreme weather, hailstorms, foot traffic equipment installation or removal, or the like.
[0004] 2. Prior Art
[0005] Asphalt-based roofing materials, such as roofing shingles, roll roofing and commercial roofing, are installed on the roofs of buildings to provide protection from the elements. Typically, the roofing material is constructed of a substrate such as a glass fiber mat or an organic felt, an asphalt coating on the substrate, and a surface layer of granules embedded in the asphalt coating.
[0006] The typical roofing material construction is suitable under most circumstances. However, sometimes a roofing material is subjected to environmental conditions that may damage the roofing material. For example, storms are responsible for billions of dollars in damage to roofing materials every year. During storms, hailstones may impact the roofing material, which may cause tears or punctures in the roofing material. The hailstone impacts may also cause an immediate loss of some granules from the impacted areas of the roofing material and a further loss of granules from those areas over time. The loss of granules creates an unattractive appearance and leaves the asphalt coating in those areas unprotected from the degrading effects of the elements. Even in cases where there are no obvious fabric ruptures the roof may be compromised since the exposed asphalt may prematurely age compromising the roof and/or adversely affecting the esthetics. Similarly foot traffic in hot weather can “scuff” the roof surface affecting the esthetics and ultimate durability of the roof. The installation of equipment or its removal can put holes in the roof with the potential to leak.
[0007] Losses sustained to building roofs caused by climatic conditions such as hail storms has focused development of roofing materials having increased impact resistance, and having an improved ability to withstand the destructive forces of storms. This need in the art is particularly acute in those geographic areas which are subject to these climatic conditions. Specifically, such areas as the Plain and Rocky Mountain states are particularly subject to roofing damage caused by hailstorms and the like. Indeed, the insurance laws of the state of Texas provide cash rebates to homeowners insurance policies wherein the insured property's roof employs Class 4 roof covering materials.
[0008] Further, roofing material that is storm proof has been developed in response to damages sustained by rooftops in geographic areas such as those described above. For example, U.S. Patent Publication No. 2002/0110679 provides for a storm proof roofing material where a protective coating is applied to the upper surface of the asphalt coating.
[0009] It is known to apply a surface coating onto a roof after the roofing shingles have been installed to protect the shingles from granule loss and other damage. Unfortunately, surface coatings require additional labor to apply after the roofing shingles have been installed, they are relatively expensive, and they may create safety problems by producing a slick roof. It is also known to manufacture roofing materials with polymer-modified asphalt to provide some improvement in impact resistance. Unfortunately, roofing materials made with polymer-modified asphalt are more difficult to manufacture, handle, store and install, and they are more expensive, than roofing materials made with conventional roofing asphalt. Also, the rubber-modified asphalt shingles are not completely effective in resisting impacts.
[0010] Also, when damage is sustained by the roofing, whether the impact resisting and storm proofing materials are used or not, the entire roofing of the structure may need to be replaced. This is a very expensive project for the owner, and can also take a long period of time for the complete replacement of the roof.
[0011] The above remarks establish the need in the art for a cheap and easy to install type of replacement for roofing material that has been damaged by hail storms or other conditions, and that does not require replacement of the entire roofing when the roofing has been partly damaged.
SUMMARY OF THE INVENTION
[0012] The present invention provides a repair patch that protects and covers damaged areas of shingles or other roofing materials. Accordingly, a repair swatch for a damaged area of a roofing material is provided, the repair swatch comprising a front face having granules, and a back face having an adhesive to secure the repair swatch onto the roofing material. Further, the granules on the front face match granules on the roofing material. The roofing material can comprise a shingle. The adhesive is selected from a group consisting of a rubber polymer-modified asphalt, an acrylic, a polyurethane, a silicone and a rubber polymer. The repair swatch can be of a size that covers the damaged area of the roofing material. The shape of the repair swatch can be selected from a group consisting of square, rectangular, circular and dragon tooth.
[0013] Further, a method of repairing a damaged area of a roofing material is provided, the method comprising covering the damaged area of the roofing material with a repair swatch having a front side with granules, and securing a back side of the repair swatch to the roofing material.
[0014] The above and other features of the invention, including various novel details of construction and combinations of parts, will now be more particularly described with reference to the accompanying drawings and pointed out in the claims. It will be understood that the particular device embodying the invention is shown by way of illustration only and not as a limitation of the invention. The principles and features of this invention may be employed in various and numerous embodiments without departing from the scope of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] These and other features, aspects, and advantages of the apparatus and methods of the present invention will become better understood with regard to the following description, appended claims, and accompanying drawings where:
[0016] FIG. 1 is a perspective view of a section of roof laid with shingles, with one or more shingles being damaged;
[0017] FIG. 2 illustrates a repair swatch in accordance with the principles of the present invention; and
[0018] FIG. 3 shows an application of the repair swatch of FIG. 2 to a section of roof laid with one or more damaged shingles as shown in FIG. 1 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0019] Although this invention is applicable to numerous and various types of roofing materials, it has been found particularly useful in the environment of roofing shingles. Therefore, without limiting the applicability of the invention to the above, the invention will be described in such environment.
[0020] With reference now to the drawings, the present invention will be described. As shown in FIG. 1 , a roof is generally laid out with many shingles in a formation such as shown in the figure. Each roofing shingle 10 generally includes a rectangular sheet 11 of asphalt-impregnated substrates, including webs, scrims, and felts of fibrous material, such as mineral fibers, cellulosic fibers, rag fibers, synthetic fibers and mixtures thereof. The asphalt coating employed in the production of roofing shingles encompass any type of bituminous material suitable for use as a roofing material. Thus, asphalts, tars, pitches and mixtures thereof are all encompassed within the meaning of the term “asphalt coating.” The asphalt can be either a manufactured asphalt, produced by refining petroleum, or a naturally occurring asphalt. The asphalt coating can include various additives and/or modifiers, such as inorganic fillers, mineral stabilizers, organic materials including polymers, recycled streams or ground tire rubber.
[0021] Each rectangular sheet 11 has a headlap portion 12 , and a butt portion 13 which is divided into spaced apart tabs 14 . An elongated strip 16 is secured to the sheet 11 at a position underlying the tabs 14 . Preferably, a lower marginal edge 17 of the headlap portion 12 slightly overlaps an upper marginal edge 18 of the strip 16 and is secured thereto by asphaltic adhesive or other suitable means to ensure a watertight seal between the sheet 11 and strip 16 . Each tab 14 is further secured to the strip 16 by adhesive or other suitable means.
[0022] The asphalt coating may include fillers, in the form of inorganic particulates or mineral stabilizers. Granules 15 are deposited in and over the top or exposed asphalt coating, such that granules 15 are deposited on the sheet 11 and the strip 16 . During hail storms, it is these granules 15 that are damaged and are separated from the shingles 10 . Damaged areas 20 of the shingles 10 therefore lack the protection provided by the granules 15 , and the asphalt portion 30 of the shingle 10 is exposed. For purposes of description of the present invention, two damaged areas 20 are shown on the shingles laid out on the rooftop, with the exposed asphalt portions 30 showing. Obviously, more or less areas of the rooftop can be damaged.
[0023] The present invention provides a repair swatch 100 , as shown in FIGS. 2( a ) and 2 ( b ). FIG. 2( a ) shows a repair swatch having a square shape, and FIG. 2( b ) shows a repair swatch having a “dragon tooth” shape. Many different shapes are contemplated by the present invention, including but not limited to rectangular, circular, trapezoidal, etc., and are not limited by the shapes as shown in the figures. The size of the repair swatch can be of any size, and is preferably manufactured in many different sizes. Thus, a consumer can purchase the appropriate size depending on the size of the damaged area 20 .
[0024] Each repair swatch has a front face 101 and a back face 102 . The front face 1010 f the repair swatch has granules 15 that match the granules 15 of the shingles 10 . The back face 102 of the repair swatch contains an adhesive that allows the patch 100 to be secured onto the shingle 10 , and specifically, the damaged area 20 of the shingle 10 . Any type of adhesive that can secure the repair swatch onto the roofing material, or shingle, can be used, such as but not limited to a rubber polymer-modified asphalt, an acrylic, a polyurethane, a silicone or a rubber polymer. Different types and colors of granules 15 can be used, and the consumer can purchase the specific repair swatch 100 that matches the colors of the granules on the shingles or roofing of his/her particular roof.
[0025] FIG. 3 shows the application of the repair swatch of FIG. 2 on the damaged areas 20 of the shingles 10 of FIG. 1 . For purposes of the figure, a “dragon tooth” shape repair swatch 100 is placed on the damaged area of shingle 10 a, and a square shape repair swatch 100 is placed on the damaged area of shingle 10 b. The backside 102 of the repair swatch has the adhesive which is used to secure the repair swatch 100 onto the shingles 10 a, 10 b. The front face 101 has granules 15 that match the size and shape of the granules 15 of the shingles 10 a, 10 b. From a distance, the border of the repair swatch 100 cannot be seen as the granules 15 on the shingle 10 and repair swatch 100 match, so that it appears that the shingles 10 a and 10 b were never damaged.
[0026] The present invention provides several advantages that solve the problems with prior art methods. The repair swatch 100 provides the same protection as a brand new shingle would, making it a cheaper alternative to replacing shingles and/or the entire roofing. The granules on the front face of the repair swatch match the granules on the shingle, so that it is nearly impossible to tell that a repair swatch was placed on the shingle or that the shingle was ever damaged. The repair swatches come in various sizes and shapes, so that appropriate ones can be used or trimmed to size depending on the size and shape of the damaged area on the shingle or roofing material. Further, different colors and sizes of granules can be used on different sizes and shapes of repair swatches, so that the appropriate one can be used to match the damaged area of the particular shingle or roofing.
[0027] The above description of the present invention is only the preferred embodiment of the invention. Embodiments may include any currently or hereafter-known versions of the elements described herein. Different types, sizes, colors of granules can be used. Different sizes and shapes of repair swatches can be used, and any known adhesive can be used to secure the repair swatch securely to the shingle or roofing material. Although the invention was described in regard to damaged shingles, it is understood that the invention can be used on any type of applicable roofing material in accordance with the same principles described herein, and is not limited to shingles.
[0028] While there has been shown and described what is considered to be preferred embodiments of the invention, it will, of course, be understood that various modifications and changes in form or detail could readily be made without departing from the spirit of the invention. It is therefore intended that the invention be not limited to the exact forms described and illustrated, but should be constructed to cover all modifications that may fall within the scope of the appended claims.
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A repair swatch (such as a patch) is provided that is preferably covered with appropriate granules on one face, with an opposite (back) face having an adhesive that allows the material to be placed over and adhere to small damaged areas of shingles and/or other types of roofing. The size, shape and color of the patch are such that it closely matches that of the existing shingle. Further, the size and shape of the patch are similar to shapes on laminated shingle products rendering the repair essentially invisible on such products.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a process of reducing friction, which is encountered in molds utilized in injection molded solder processing.
2. Background Art
In the fabrication of mold plates, which are utilized for purposes of injection molded solder processes, particularly those employed to produce semiconductor chip connection processes, for instance, such as for the controlled collapse chip connect new process (C4NP), the normally glass material mold plates are generally produced utilizing an etching process which causes the surface of the mold plates to be provided with mold pits or cavities. These etched mold pits in the mold plate surfaces are frequently encountered in possessing sharp edges, whereby the sharp edges have a tendency to abrade the mold fill head o-rings of the mold apparatus. This may cause debris from the o-rings to be located on or embedded in the mold plate, which is equipped with pits or cavities to be filled with solder in order to produce the solder connections. Consequently, this presence of the sharp pit edges may result in defects in the components and operation of the molding apparatus, and in a reduced service life for the o-rings due to excessive wear during the employment thereof.
Moreover, the abrasive phenomenon which is encountered through the presence of the sharp edges of the etched pits in the surface of the mold plates, may also lead to an increase in friction forces opposing the motion of the mold plates during operation of the molding apparatus, potentially producing a reduction in operating margins or efficiency caused by a twisting of the fill head while dispensing the solder into the cavities which are to be filled therewith. Moreover, the resultant increase in friction may also generate debris deposited on the mold plate surface, which emanates from the fill head seal of the apparatus, thereby rendering the mold filling process subject to considerable difficulties.
Generally, as indicated, the mold plates may be constituted of a material such as glass, the property of which may be considered as constituting a “solid liquid” in the technology, and which, at elevated temperatures, acts in many instances like any other liquid, with forces due to surface tension, viscosity and interaction with neighboring materials comprising a determining in its behavior and characteristic.
In this instance, surface tension forces may possess a tendency to soften any sharp edges in the pits, which have been formed in the surface of the glass mold plates, and whereby an increase in the temperature to levels at which these forces can overcome the viscosity over a period of time at elevated temperatures may tend to smooth or round off the sharp edges of the mold pits.
SUMMARY OF THE INVENTION
Accordingly, in order to alleviate the problems which are encountered in the presence of sharp edges in mold pits on the mold plate surface, the edges of the mold pits can be radiused or smoothed and resultingly rounded off through the intermediary of a heat treatment imparted to the glass mold plate at a temperature which is sufficiently high and over a sufficient duration of so as to enable the surface tension forces in a glass material which approaches a “near melting” or lowered viscosity condition to soften the sharp edges of the mold edge pits without substantially affecting the overall shape and volume of the mold pits. Some minor degree of alteration in shape and/or volume may be encountered, but can be precedingly compensated for during the etching of the mold pits.
Alternatively, some type of a mechanical polishing process with a compliant backing and polishing compound may be another method employed in accomplishing the smoothing of the pit edges, but may be somewhat more difficult to control and be more expensive in the implementation thereof than the process of heat treating the glass mold plate, as proposed by the present invention. Moreover, it may also be possible to utilize a surface, rather than a bulk or through-extending heat treatment, in effect, treating only the surface of the mold plate, rather than the entire thickness thereof, but this may involve an increase in stresses and difficulties in controlling the pit edge smoothing or radiusing process. Consequently, a bulk heat treatment process may be more advantageous in reducing surface texture of the glass mold plate, and thereby further reducing friction attributable to the flat areas of the glass mold plate material.
In order to attain the foregoing pit edge smoothing effect, it may be advantageous to increase the temperature of the glass mold plate up to a range of approximately 760° C., in essence, approximately 60° C. below the “softening” temperature of glass material, and to then reduce the temperature over a period of time, whereby this maximum temperature level, although well above the “annealing” temperature of the glass, may be designated as a “heat-treatment”, rather than an annealing of the glass, per se.
Furthermore, other aspects may be considered in identifying the optimum heat treating time and temperature profile imparted to the glass mold plate in order to appropriately soften the mold pit edges, whereby possibly two kinds of substrate coatings, such as graphite and a refactory kiln wash on a substrate on which the glass plate is mounted, may be considered in addressing the problem of mold sticking to a substrate on which it is heat treated.
Possibly, particularly if a graphite substrate is to be employed, it may be desirable to control the heat-treatment environment in order to restrict the presence of oxygen. Another approach may be to coat a substrate or the back surface of the mold plate with a sacrificial or possibly permanent layer in order to prevent sticking between the components. An oxide or nitride possessing a sufficient temperature stability may also be employed, whereby if the coating layer is to be permanent, in essence, not sacrificial to require being removed subsequent to treatment, the coating layer may be applied to the backside of the mold plate, rather than to the substrate.
A substrate, which is adapted to be utilized in order to support the backside of the glass mold plate, may have to be flat and stable throughout the temperature cycle which is imparted to the mold plate, and whereby a material choice among other suitable materials may be that of quartz. There may also be provided a stable substrate material, which the glass mold plate will not adhere to at elevated temperatures, and moreover, lengthier time intervals at lower heat treatment temperatures may possibly mitigate sticking between the substrate and the glass mold plate being treated while maintaining the desired mold plate pit edge modifications.
In essence, during the heat-treatment of the glass mold plate, the underlying substrate must be of an essentially completely or precisely flat or panel configuration, inasmuch as treatments that are implemented when the substrates are not acceptably flat or planar, may produce unacceptably deformed mold pit configurations.
Necessarily, the substrate is required to be stable in both of its mechanical and chemical characteristics under extremely large temperature ramping cycles, whereby as indicated, a material such as quartz for the substrate may be an acceptable choice.
In as much as elevated temperatures cause other liquid aspects to come into consideration or play, in particular, such as “wetting” or its equivalent, an initial experimentation with a mold plate located on a quartz substrate resulted in the mold plate sticking to the substrate and possibly damaging both the mold plate and the substrate, requiring that a further investigation be made that the temperature ramping up and ramping down process or cycling may not be a well-controlled aspect and exact time at the treatment temperature can vary significantly so as to render an issue the consideration of uniformities and temperature and duration of time across a large surfaced mold plate utilizing such an approach.
BRIEF DESCRIPTION OF THE DRAWINGS
Reference may now be made to the following detailed description of a preferred embodiment of the invention in the effectuating heat treatment of glass mold plates having mold pits or cavities etched therein, wherein:
FIGS. 1A and 1B illustrate, respectively, plan and side spectroscopic views of a mold plate pit in an initially untreated configuration;
FIGS. 2A and 2B illustrate, respectively, plan and side spectroscopic views of the mold plate pit in a post heat-treatment stage; and
FIG. 3 illustrates a graphical representation of a process window work in progress.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIGS. 1A and 1B of the drawings, there is spectroscopically illustrated a typical pit or cavity 10 , which has been etched into the upper surface 12 of a glass mold plate 14 , and which shows the peripheral edge 16 of the pit having a relatively sharp configuration at the meeting location with the plate surface, which can readily cause undue damage to be sustained by o-rings of the apparatus and adversely affect the operation of the molding apparatus, such as be a deposition of debris and particulate contaminants of the mold plate surface and in the mold cavities. Moreover, the sharp edge 16 of the mold pit 10 may result in a shortened service life for the o-ring and also adversely affect the functioning of the fill head of the mold apparatus.
As illustrated in FIGS. 2A and 2B of the drawings, wherein the glass mold plate 14 has been heat-treated at the temperatures such as from about 740° C. to about 800° C. for a predetermined period of time, preferably within about 1 minute to about 20 minutes. In that instance, the peripheral edge 16 of the mold pit 10 in the surface 12 of the glass mold plate 14 has been radiused and shown to be in a smoother rounded-off configuration, thereby reducing or eliminating the sharpness of the edge, so as to have a reduced tendency to adversely affect the process of injection molded soldering for which the glass mold plate 14 is employed. Further experiments indicate that in one useful case, the borosilicate glass mold plate is heated to 760° C. and held there for 10 minutes before being allowed to cool.
Quite evidently, the heat-treatment of the glass mold plate 14 will successfully increase the pit smoothing at the edge 16 thereof, with no significant alteration of mold pit or cavity volume. Moreover, utilizing suitable material for a flat or planar substrate 20 on which the glass mold plate 14 is mounted will also enable the heat-treatment to be implemented without any adverse effect on the planarity and quality of the upper mold plate surface 12 . Other substrate materials besides quartz, such as graphite plates, may also be successfully employed, as well as different temperature and time cycles for the heat treatment. Moreover, a coating of materials may also be utilized, such as a graphite powder, and other materials, which are being investigated. This may provide a solution to the “sticking” problem between the mold plate and substrate, which has been encountered to some extent in connection with the foregoing process. Best results have been obtained utilizing a refectory kiln wash such as “AMACO Kiln Wash.”
As illustrated in FIG. 3 of the drawings, showing a graphical representation of viscosity versus temperature and degrees in centigrade, a treatment at lower temperatures with a controlled dwelling time period may provide for a more manufacturing-friendly process work window in the treatment of the glass mold plate, in order to reduce the sharp edges of the mold pits, and wherein this aspect may be predicated on different factors depending upon the types of materials being employed.
While the present invention has been particularly shown and described with respect to preferred embodiments thereof, it will be understood by those skilled in the art that the foregoing and other changes in forms and details may be made without departing from the spirit and scope of the present invention. It is therefore intended that the present invention not be limited to the exact forms and details described and illustrated, but to fall within the spirit and scope of the appended claims.
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A process of reducing friction, which is encountered in molds utilized in injection molded, solder processing, and wherein glass mold plates have mold pits etched therein. The mold pates are subjected to a heat treatment so as to smooth or round-off sharp edges along the periphery of the mold pits.
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FIELD OF THE INVENTION
[0001] The present invention relates generally to the field of video coding. More particularly, the present invention relates to scalable video coding and decoding.
BACKGROUND OF THE INVENTION
[0002] This section is intended to provide a background or context to the invention that is recited in the claims. The description herein may include concepts that could be pursued, but are not necessarily ones that have been previously conceived or pursued. Therefore, unless otherwise indicated herein, what is described in this section is not prior art to the description and claims in this application and is not admitted to be prior art by inclusion in this section.
[0003] Video coding standards include ITU-T H.261, ISO/IEC MPEG-1 Visual, ITU-T H.262 or ISO/IEC MPEG-2 Visual, ITU-T H.263, ISO/IEC MPEG-4 Visual and ITU-T H.264 (also known as ISO/IEC MPEG-4 AVC). In addition, there are currently efforts underway with regards to the development of new video coding standards. One such standard under development is the scalable video coding (SVC) standard, which will become the scalable extension to the H.264/AVC standard.
[0004] Conventional video coding standards such as MPEG-1, H.261/263/264 encode video either at a given quality setting or at a relatively constant bit rate via the use of a rate control mechanism. If the video needs to be transmitted or decoded at a different quality, the data must first be decoded and then re-encoded using the appropriate setting. In some scenarios, such as in low-delay real-time applications, this “transcoding” procedure may not be feasible.
[0005] Scalable video coding overcomes this problem by encoding a “base layer” with some minimal quality, and then encoding enhancement information that increases the quality up to a maximum level. In addition to selecting between the “base” and “maximum” qualities through inclusion or exclusion of the enhancement information in its entirety, the enhancement information may often be truncated at discrete points, permitting intermediate qualities between the “base” layer and “maximum” enhancement layer. In cases where the discrete truncation points are closely-spaced, the scalability is referred to as being “fine-grained,” from which the term “fine grained scalability” (FGS) is derived. A “progressive-refinement (PR) slice,” which is also known as FGS, is introduced in Annex F of the H.264/AVC video coding standard.
[0006] A key characteristic of FGS slices is that their truncation results in an almost proportional loss of perceptual quality. For example, truncating a FGS slice to 75% of its original length may result in losing 25% of the perceptual benefit attributable to the FGS slice, as opposed to a catastrophic failure whereby 90% of the perceptual benefit is lost.
[0007] In fine grain scalability, transform coefficients are encoded in successive refinements, starting with the minimum quality provided by AVC compatible intra/residual coding. This is accomplished by repeatedly decreasing the quantization step size and applying a modified entropy coding process similar to sub-bitplane coding. For each quality enhancement layer, the coding process for the transform coefficient refinement levels is divided into two scans. Coefficients that were not zero in the previous layer (or layers) are classified as belonging to a “significance pass.” Other coefficients belong to the “refinement pass.” The entropy coding mechanism used for a given coefficient depends on whether it was classified as belonging to the “significance pass” or the “refinement pass.” In practice, the two passes may be interleaved, so that a coefficient belonging to the refinement pass is coded between two coefficients belonging to the significance pass; however, the distinction in entropy coding remains.
[0008] When variable length codes (VLCs) are used to code coefficients in FGS slices, coefficient magnitudes are initially assumed to be 0 or 1. Coefficient magnitudes of two or greater are generally rare, and are due to H.264/AVC features such as isolated coefficient removal. To include magnitudes greater than one in the VLC design when these magnitudes have a low probability would lead to a design with reduced coding efficiency. Instead, information about the number of coefficients in a block with magnitude greater than 1, and the maximum magnitude in the block, is embedded into the end-of-block (EOB) symbol. Any such “high magnitude” coefficients are then coded following the EOB symbol. It is desirable to code these “high magnitude” coefficients in the most efficient way possible.
[0009] According to Annex F of the H.264/AVC standard, information about the number of coefficients with magnitude greater than 1 (CountMag2), and the maximum magnitude (MaxMag), is extracted from EOB symbol using the following pseudo-code:
[0000]
if ( EOBsymbol < NumSigCoeff*2 )
{
MaxMag = (EOBsymbol % 2) + 2;
CountMag2 = (EOBsymbol / 2) + 1;
} else {
MaxMag = (EOBsymbol / NumSigCoeff) + 2;
CountMag2 = (EOBsymbol % NumSigCoeff) + 1;
}
[0010] NumSigCoeff indicates the number of coefficients that were found to have a magnitude of 1 or greater. This value is known from the coefficients coded prior to the EOB symbol. The “%” symbol indicates the “modulus” operator (or “remainder when divided by”).
[0011] As an example, one can assume a vector of significance pass coefficients is {0, 0, 1, 0, 1, 2, 1, 0}. When decoding, all magnitudes would initially be decoded as 1, i.e. {0, 0, 1, 0, 1, 1, 1, 0}, followed by an EOBsymbol=0. The NumSigCoeff value is known to be 4 from the decoded coefficient values. According to the above pseudo-code, MaxMag=(0% 2)+2=2, and CountMag2=(0/2)+1=1. Therefore, it is known that one out of the four non-zero coefficients has a magnitude of two. The only remaining question is which one out of the four has this magnitude.
[0012] The location and exact magnitudes of the coefficients are decoded using exp-Golomb codes. However, since the values of MaxMag and CountMag2 are known, it is sometimes possible terminate coding early. Continuing the above example, there are four coefficients decoded with magnitude 1. These can be written as {1, 1, 1, 1}. It is also recalled that the original coefficient values are {1, 1, 2, 1}. In decoding the exp-Golomb codes, a zero bit is decoded for the first of these coefficients, indicating that its magnitude is no greater than 1. Similarly, a zero is decoded for the second coefficient. For the third coefficient, the exp-Golomb code can be truncated and simply decoded as “1” rather than “1 0” since the maximum magnitude (MaxMag) is known. The fourth coefficient does not need to be refined at all, since it is known that CountMag2=1. Therefore, only 3 bits are required to refine the “high magnitude” values instead of 5 that would be needed if complete exp-Golomb codes were used.
[0013] Unfortunately, there are two problems with the existing approach depicted above. First, the formula used to compute MaxMag and CountMag2 from the EOB symbol is designed based on the assumption that these values are typically small (for example, less than 4). When either or both of these values are large, the number of bits required to code the EOB symbol itself becomes prohibitively large. Because motion compensation has recently been added to FGS slices, the possibility of this problem occurring is now greater than when the scheme was initially designed. Second, the exp-Golomb may not be the most efficient VLC when the values of MaxMag or CountMag2 are large. For example, in some situations it may be better to code the magnitude of each coefficient using a binary representation rather than exp-Golomb. In other situations, it may be better to use a trained VLC known to both encoder and decoder.
SUMMARY OF THE INVENTION
[0014] The present invention provides an improved coding efficiency while coding the transform coefficient refinement levels. The invention observes the high likelihood of the high-magnitude refinement coefficient levels under certain coding conditions, and advantageously determines tradeoff thresholds to adapt the coding of the EOB symbol that conveys information associated with the remaining number of coefficients in a block with magnitude greater than 1, as well as the maximum magnitude in the block. The present invention also proposes a variable-length coding (VLC) method to encode high magnitude values, wherein the VLC table to be used is conveyed in the EOB symbol. The present invention results in an improvement in coding efficiency over conventional arrangements.
[0015] The present invention can be implemented directly in software using any common programming language, e.g. C/C++, or assembly language. The present invention can also be implemented in hardware and used in a wide variety of consumer devices.
[0016] These and other advantages and features of the invention, together with the organization and manner of operation thereof, will become apparent from the following detailed description when taken in conjunction with the accompanying drawings, wherein like elements have like numerals throughout the several drawings described below.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] FIG. 1 shows a generic multimedia communications system for use with the present invention;
[0018] FIG. 2 is a perspective view of a mobile telephone that can be used in the implementation of the present invention; and
[0019] FIG. 3 is a schematic representation of the circuitry of the mobile telephone of FIG. 2 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0020] FIG. 1 shows a generic multimedia communications system for use with the present invention. As shown in FIG. 1 , a data source 100 provides a source signal in an analog, uncompressed digital, or compressed digital format, or any combination of these formats. An encoder 110 encodes the source signal into a coded media bitstream. The encoder 110 may be capable of encoding more than one media type, such as audio and video, or more than one encoder 110 may be required to code different media types of the source signal. The encoder 110 may also get synthetically produced input, such as graphics and text, or it may be capable of producing coded bitstreams of synthetic media. In the following, only processing of one coded media bitstream of one media type is considered to simplify the description. It should be noted, however, that typically real-time broadcast services comprise several streams (typically at least one audio, video and text sub-titling stream). It should also be noted that the system may include many encoders, but in the following only one encoder 110 is considered to simplify the description without a lack of generality.
[0021] The coded media bitstream is transferred to a storage 120 . The storage 120 may comprise any type of mass memory to store the coded media bitstream. The format of the coded media bitstream in the storage 120 may be an elementary self-contained bitstream format, or one or more coded media bitstreams may be encapsulated into a container file. Some systems operate “live”, i.e. omit storage and transfer coded media bitstream from the encoder 110 directly to the sender 130 . The coded media bitstream is then transferred to the sender 130 , also referred to as the server, on a need basis. The format used in the transmission may be an elementary self-contained bitstream format, a packet stream format, or one or more coded media bitstreams may be encapsulated into a container file. The encoder 110 , the storage 120 , and the sender 130 may reside in the same physical device or they may be included in separate devices. The encoder 110 and sender 130 may operate with live real-time content, in which case the coded media bitstream is typically not stored permanently, but rather buffered for small periods of time in the content encoder 110 and/or in the sender 130 to smooth out variations in processing delay, transfer delay, and coded media bitrate.
[0022] The sender 130 sends the coded media bitstream using a communication protocol stack. The stack may include but is not limited to Real-Time Transport Protocol (RTP), User Datagram Protocol (UDP), and Internet Protocol (IP). When the communication protocol stack is packet-oriented, the sender 130 encapsulates the coded media bitstream into packets. For example, when RTP is used, the sender 130 encapsulates the coded media bitstream into RTP packets according to an RTP payload format. Typically, each media type has a dedicated RTP payload format. It should again be noted that a system may contain more than one sender 130 , but for the sake of simplicity, the following description only considers one sender 130 .
[0023] The sender 130 may or may not be connected to a gateway 140 through a communication network. The gateway 140 may perform different types of functions, such as translation of a packet stream according to one communication protocol stack to another communication protocol stack, merging and forking of data streams, and manipulation of data streams according to the downlink and/or receiver capabilities, such as controlling the bit rate of the forwarded stream according to prevailing downlink network conditions. Examples of gateways 140 include multipoint conference control units (MCUs), gateways between circuit-switched and packet-switched video telephony, Push-to-talk over Cellular (PoC) servers, IP encapsulators in digital video broadcasting-handheld (DVB-H) systems, or set-top boxes that forward broadcast transmissions locally to home wireless networks. When RTP is used, the gateway 140 is called an RTP mixer and acts as an endpoint of an RTP connection.
[0024] Alternatively, the coded media bitstream may be transferred from the sender 130 to the receiver 150 by other means, such as storing the coded media bitstream to a portable mass memory disk or device when the disk or device is connected to the sender 130 and then connecting the disk or device to the receiver 150 .
[0025] The system includes one or more receivers 150 , typically capable of receiving, de-modulating, and de-capsulating the transmitted signal into a coded media bitstream. De-capsulating may include the removal of data that receivers are incapable of decoding or that is not desired to be decoded. The codec media bitstream is typically processed further by a decoder 160 , whose output is one or more uncompressed media streams. Finally, a renderer 170 may reproduce the uncompressed media streams with a loudspeaker or a display, for example. The receiver 150 , decoder 160 , and renderer 170 may reside in the same physical device or they may be included in separate devices.
[0026] Scalability in terms of bitrate, decoding complexity, and picture size is a desirable property for heterogeneous and error prone environments. This property is desirable in order to counter limitations such as constraints on bit rate, display resolution, network throughput, and computational power in a receiving device.
[0027] Various embodiments of the present invention provide improved coding efficiency while coding the transform coefficient refinement levels by addressing two principal problems with the conventional approach to coding “high magnitude” coefficients in Annex F of H.264/AVC: the EOB symbol itself and the VLC used to refine high magnitude coefficients. The invention observes the high likelihood of the high-magnitude refinement coefficient levels under certain coding conditions, and advantageously determines tradeoff thresholds to adapt the coding of the EOB symbol that conveys information associated with the remaining number of coefficients in a block with magnitude greater than 1, as well as the maximum magnitude in the block. For example, the tradeoff thresholds may be determined according to an input signal which limits either or both the values of MaxMag and CountMag2.
[0028] In one embodiment of the invention, MaxMag is capped so that a value of MaxMag=4 indicates that the block contains at least one coefficient with value of 4 or higher. In this case, the precise value of MaxMag is unknown, and coding of the exp-Golomb codes cannot be terminated early, which is contrary to what occurs in conventional arrangements as discussed previously. Although this may result in a few extra bits being coded, the EOB symbol is potentially much smaller, thus requiring fewer bits and resulting in a net saving of bits.
[0029] In another embodiment of the invention, CountMag2 is capped so that a value of CountMag2=6 indicates that the block contains at least 6 coefficients with magnitude greater than 1. The precise value of CountMag2 is unknown so that coding of the exp-Golomb codes could not be terminated early. Although this may also result in a few extra bits being coded, the EOB symbol is potentially much smaller, thus requiring fewer bits and resulting in a net saving of bits.
[0030] In still another embodiment of the present invention, the cap on CountMag2 is not a constant number, but instead is at least partially relative to the number of non-zero coefficients in the block, NumSigCoeff. For example, a value of CountMag2 in the range 1.3 may indicate the exact number of coefficients with a magnitude greater than 1; CountMag2=4 may indicate that at least the greater of 4 or half of NumSigCoeff coefficients have a magnitude greater than 1; and CountMag2=5 may indicate that at least the greater of 5 or three-quarters of NumSigCoeff coefficients have a magnitude greater than 1.
[0031] The present invention also involves the utilization of a VLC code for refining coefficients with a magnitude greater than 1. In one embodiment, the invention uses a VLC known to both the encoder and the decoder for refining coefficient magnitudes. The VLC that is selected may depend upon one or more of the values of NumSigCoeff, MaxMag, and CountMag2. For example, one VLC may be used if MaxMag<4, and a different VLC may be used if MaxMag>=4. In cases where more than one of the values NumSigCoeff, MaxMag and CountMag2 is used, a lookup table may be utilized to determine which VLC is used.
[0032] In a further embodiment of the present invention, the invention uses binary values to code coefficient magnitudes. In this embodiment, for example, given MaxMag=4, 00 means a magnitude of 1, 01 means a magnitude of 2, 10 means a magnitude of 3, and 11 means a magnitude of 4. In the event that MaxMag is not a power of two, early truncation of the coding process may be used, since not all binary values are permitted.
[0033] In still another embodiment, a VLC table to be used is embedded in the EOB symbol. This may occur along with, or instead of, the values MaxMag and CountMag2, which are already embedded in the EOB symbol. In this embodiment, the EOB symbol is a function that takes MaxMag, CountMag2 and/or the VLC table index as parameters.
[0034] In a particular embodiment of the present invention, the pseudo-code discussed previously with regard to conventional arrangements is modified as follows:
[0000]
if ( EOBsymbol < 8 )
{
MaxMag = (EOBsymbol % 2) + 2;
CountMag2 = (EOBsymbol / 2) + 1;
VLC = 1;
} else {
MaxMag = (EOBsymbol % 2 ) + 4;
CountMag2 = (EOBsymbol / 16);
VLC = 2;
}
[0035] In the above embodiment, MaxMag is capped at 5, i.e. MaxMag=5 means that the maximum coefficient magnitude is at least 5. Similarly, CountMag2 is capped at 4 for MaxMag<4. The value of EOBsymbol also provides a VLC table index to be used in refining magnitude information. In one embodiment, a VLC=1 indicates exp-Golomb, and a VLC=2 indicates a binary representation of the coefficient magnitude minus 1. It should be noted that the VLC indication may be explicitly coded. In other words, the VLC indication may be determined directly from the EOB symbol value, rather than inferred from the maximum magnitude or number of coefficients.
[0036] In another embodiment of the invention, the pseudo-code is modified as follows:
[0000]
if ( EOBsymbol < 4)
{
MaxMag = 5;
CountMag2 = 6;
VLC = EOBsymbol + 1;
} else {
MaxMag = (EOBsymbol / 4) % 4) + 1;
CountMag2 = min(6, EOBsymbol / 16);
VLC = 0;
}
[0037] In another embodiment, the VLC used for encoding high magnitude coefficients involves binarizing the magnitude values and forming a VLC codeword based on bitplane values. This can be particularly useful if the maximum magnitude (MaxMag) is small, but the number of coefficients with magnitude greater than 1 is large. For example, if the vector of coefficients is {1, 1, 2, 1, 1}, using a VLC to code the individual magnitudes of each coefficient is not very beneficial. But, if the VLC codeword is formed based on the bitplane 00100, the probability of the various magnitudes may be better approximated.
[0038] It should be noted that, although the various embodiments of the present invention described herein are described in the context of significance pass coding for FGS slices in the H.264/AVC standard, some or all of these embodiments can be similarly applied to other types of coefficients (e.g., refinement coefficients), other types of values (e.g., pixel values instead of coefficients), other slice types, or other video coders.
[0039] The mobile telephone 12 of FIGS. 2 and 3 includes a housing 30 , a display 32 in the form of a liquid crystal display, a keypad 34 , a microphone 36 , an ear-piece 38 , a battery 40 , an infrared port 42 , an antenna 44 , a smart card 46 in the form of a UICC according to one embodiment of the invention, a card reader 48 , radio interface circuitry 52 , codec circuitry 54 , a controller 56 and a memory 58 . Individual circuits and elements are all of a type well known in the art, for example in the Nokia range of mobile telephones.
[0040] Communication devices of the present invention may communicate using various transmission technologies including, but not limited to, Code Division Multiple Access (CDMA), Global System for Mobile Communications (GSM), Universal Mobile Telecommunications System (UMTS), Time Division Multiple Access (TDMA), Frequency Division Multiple Access (FDMA), Transmission Control Protocol/Internet Protocol (TCP/IP), Short Messaging Service (SMS), Multimedia Messaging Service (MMS), e-mail, Instant Messaging Service (IMS), Bluetooth, IEEE 802.11, etc. A communication device may communicate using various media including, but not limited to, radio, infrared, laser, cable connection, and the like.
[0041] The present invention is described in the general context of method steps, which may be implemented in one embodiment by a program product including computer-executable instructions, such as program code, executed by computers in networked environments. Generally, program modules include routines, programs, objects, components, data structures, etc. that perform particular tasks or implement particular abstract data types. Computer-executable instructions, associated data structures, and program modules represent examples of program code for executing steps of the methods disclosed herein. The particular sequence of such executable instructions or associated data structures represents examples of corresponding acts for implementing the functions described in such steps.
[0042] Software and web implementations of the present invention could be accomplished with standard programming techniques with rule based logic and other logic to accomplish the various database searching steps, correlation steps, comparison steps and decision steps. It should also be noted that the words “component” and “module,” as used herein and in the claims, is intended to encompass implementations using one or more lines of software code, and/or hardware implementations, and/or equipment for receiving manual inputs.
[0043] The foregoing description of embodiments of the present invention have been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the present invention to the precise form disclosed, and modifications and variations are possible in light of the above teachings or may be acquired from practice of the present invention. The embodiments were chosen and described in order to explain the principles of the present invention and its practical application to enable one skilled in the art to utilize the present invention in various embodiments and with various modifications as are suited to the particular use contemplated.
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A system and method for improved video encoding and decoding. The present invention addresses issues that arise in the H.264/AVC standard involving “high magnitude coefficients.” According to various embodiments of the present invention, an encoded end of block (EOB) symbol provides information comprising at least one of the maximum magnitude of values in a block, the number of values in the block with a magnitude greater than 1, and a variable length code (VLC) index indicating a VLC to be used in decoding precise magnitudes for non-zero values in the block. By including this information in the EOB symbol, improved coding efficiency is achieved.
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BACKGROUND OF THE PRESENT INVENTION
1. Field of Invention
The present invention relates to an advanced treatment method for water.
2. Description of Related Arts
Recent industrial and agricultural developments have led to discharges of a large amount of industrial wastewater and domestic sewage into rivers, lakes and reservoirs. While these rivers, lakes and reservoirs are usually the water source of domestic water supply for local inhabitants, the wastewater discharge has aggravated the problem of organic pollution in the water source of drinking water. Some organic pollutants, such as chemical substances which include chemical raw materials, pesticides and plasticizers, are carcinogenic, teratogenic and mutagenic. The concentration of these substances is generally low in water but the presence of these substances is extremely harmful to health because of their high level of toxicity. Conventional water treatment methods have very limited effect on the removal of these substances. For example, in Nov. 13, 2005, an accident occurred in Jilin, China. A diphenyl factory owned by China National Petroleum Corporation exploded and led to a massive nitrobenzene pollution in the Songhua River and the emergency use of activated carbon powder. This activated carbon powder provided strengthened adsorption for coagulation so that the emergency use of activated carbon powder is required to ensure the safety of drinking water because the conventional water treatment has very poor nitrobenzene removal effect on water. However, activated carbon has a problem of saturated adsorption capacity and has to be regenerated after its adsorption capacity is saturated. Hence, the cost of the use of activated carbon powder is relatively high. For removal of this type of organic substances, ozonation is another possible method. However, because of the limited ability of ozonation in which only a selective portion of the easily oxidized organic substances containing benzene ring or double bond structure can be removed, the removal of organic pollutants which are highly stable and hard-to-degrade are very difficult to achieve to the extent of complete mineralization. In order to enhance the effect of ozone on the removal of organic pollutants in water, catalytic ozonation is employed. It is generally accepted that this method can effectively remove the organic pollutants in water by promoting the decomposition of ozone in water and producing strong oxidizing hydroxyl radicals. Common catalytic processes include homogeneous catalytic ozonation which utilizes metal ions as the catalyst and heterogeneous catalytic ozonation which utilizes metal oxides and supported noble metals as the catalyst. However, the common catalytic processes also have the following drawbacks. For homogeneous catalytic ozonation, the metal ions are dissolved in water and are lost with the water flow, therefore causing secondary pollution. For heterogeneous catalytic ozonation, the metal oxides are usually in powder form and have to be supported by other materials in order to prevent loss with water flow, therefore complicated manufacturing process and higher manufacture cost are involved while the problems of low catalytic efficiency and dissolution of metal ions have adversely affected the water quality and treatment result. The supported noble metal catalyst involves high manufacturing cost and is not suitable for large-scale application. At present, there is also water treatment method for removal of organic pollutants by a combination use of metal and ozone. For example, in Chinese patent application number 20081006448.7, a method of removing organic substance in water by catalytic ozonation was disclosed in which the catalyst makes use of a mixture of zerovalent iron and filler material. However, the catalytic ozonation process produces ferric ion which causes the treated water to turn yellowish, hence adversely affects the sensory properties of water and produces poor water treatment result.
SUMMARY OF THE PRESENT INVENTION
An object of the present invention is to provide an advanced treatment method of water by combination of metal zinc and ozone so as to solve the existing problems in ozonation process which involves poor removal effect of organic pollutants, secondary pollution easily caused by the use of catalyst in catalytic ozonation, complicated manufacture process, high cost and poor treatment result.
Additional advantages and features of the invention will become apparent from the description which follows, and may be realized by means of the instrumentalities and combinations particular point out in the appended claims.
According to the present invention, the foregoing and other objects and advantages are attained by an advanced treatment method of water by a combination of metal zinc and ozone, comprising the steps of: placing metal zinc into an ozone contact reactor; and introducing water subject to treatment into the reactor at a flow rate of 1˜50 m/h while at the same introducing ozone to the water subject to treatment so that the ozone, the metal zinc and the water contact adequately, wherein a hydraulic retention time of the water subject to treatment in the reactor is 1˜200 min and the amount of the ozone which is introduced into the water subject to treatment is 0.1-100 mg per liter water subject to treatment.
According to the preferred embodiment of the present invention, the metal zinc has a strip-like structure having a width of 1 cm˜10 cm and a thickness of 1 mm˜1 cm and is woven into a mesh structure having a grid size of 1 cm 2 ˜100 cm 2 ; the metal zinc has a thread-like structure having a diameter of 1 μm˜1 cm and is woven into a mesh structure having a grid size of 1 mm 2 ˜100 cm 2 ; the metal zinc has a granular structure having a grain size of 1 mm˜10 cm; and/or the metal zinc has a powder structure having a particle size of 10 μm˜1 mm.
The principle of advanced treatment method for water according to the present invention is as follows: the present invention provides a method which utilizes a combination of metal zinc and ozone of which the metal zinc serves as a catalyst for rapid catalytic decomposition of ozone to produce strong oxidizing intermediates (such as hydroxyl radicals or peroxyl radicals) through redox reaction between the metal zinc and the ozone. These strong oxidizing intermediates are capable of oxidizing the organic pollutants in the water subject to treatment into water and carbon dioxide. At the same time, the metal zinc and the ozone produce zinc oxides and hydroxides on their surface respectively in such a manner that the zinc oxides and the hydroxides bind together to form an orderly 3-dimensional organized structure which has good dispersion properties without occurrence of agglomeration. The organized structure provides a large number of oxygen vacancies on its surface and many dangling bonds, therefore capable of bonding to the organic pollutants which is hard to oxidize and remove to form a mesh floc (bridging function). The mesh floc can further adsorb organic pollutants in water and increase the removal efficiency of organic pollutants in water. In addition, zinc oxides and hydroxides have larger surface area ratio and higher reactivity, and their catalytic and adsorption abilities are strong, therefore allowing further adsorption of organic pollutants and ozone in water, causing the increase in localized concentration of organic pollutants, accelerating the reaction between ozone and organic pollutants under catalysis of zinc oxides and hydroxides, enhancing the oxidation efficiency of ozone and facilitating the removal of organic pollutants in water.
The advanced treatment method of water by combination of metal zinc and ozone according to the preferred embodiment of the present invention has the following advantageous effect:
1. The metal zinc which is utilized in the present invention is readily available without special preparation, therefore the cost of treatment is lowered;
2. The advanced treatment method of water by combination of metal zinc and ozone of the present invention has high removal efficiency for organic pollutants and produces good treatment result. In addition, the water after treatment is clear and transparent with good looking perception. The treatment method of the present invention can achieve a removal rate or 90% or above for removal of nitrobenzene, chlorobenzoic acid, diethyl phthalate, dibutyl phthalate and p-chloronitrobenzene.
3. The advanced treatment method of water by a combination of metal zinc and ozone of the present invention can utilize metal zinc processed into different shapes or structures without imposing any support requirement and easily manufactured. The water after treatment is analyzed by zinc ion detector and the test result shows that the water after treatment does not contain zinc ion. Therefore it is indicated that the method of the present invention does not produce secondary pollution. Moreover, the metal zinc catalyst of the present invention can be recycled and re-used, which is cost saving.
4. The advanced treatment method of water by combination of metal zinc and ozone of the present invention employs simple steps and is easy to operate. It can also be used in conjunction with existing water treatment processes and is suitable and applicable for modification or upgrade of a variety of water treatment plants.
Still further objects and advantages will become apparent from a consideration of the ensuing description and drawings. These and other objectives, features, and advantages of the present invention will become apparent from the following detailed description, the accompanying drawings, and the appended claims.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The embodiment of the present invention as shown and described below is exemplary only and not intended to be limiting. Therefore, this invention includes all modifications or any combination encompassed within the spirit and scope of the followings.
Embodiment 1
The advanced treatment method for water by a combination of metal zinc and ozone according to this embodiment is realized by the following steps: placing metal zinc into an ozone contact reactor; and introducing water subject to treatment into the ozone contact reactor at a flow rate of 1˜50 m/h while at the same to introducing ozone to the water subject to treatment so that the ozone, the metal zinc and the water subject to treatment are contacted adequately, wherein a hydraulic retention time of the water subject to treatment in the ozone contact reactor is 1˜200 min and an amount of the ozone which is introduced into the water subject to treatment is 0.1-100 mg per liter of the water subject to treatment.
According to this embodiment, through controlling the flow rate of the water subject to treatment, the ozone, the metal zinc and the water subject to treatment are contacted adequately such that the ozone and the metal zinc have complete reaction.
According to this embodiment, the metal zinc is placed into the ozone contact reactor through a fixed-bed or a fluidized-bed arrangement. The ozone contact reactor is a tubular reactor, a tank reactor or a tower reactor.
According to this embodiment, the water subject to treatment is guided to flow into the reactor in a cocurrent manner, a countercurrent manner or a mixture of concurrent and countercurrent manner.
According to this embodiment, a removal efficiency of nitrobenzene, p-chlorobenzoic acid, diethyl phthalate, dibutyl phthalate and p-chloronitrobenzene from the water subject to treatment can reach 90% or above. The efficiency of advanced treatment method for water according to this embodiment is good. Compared to conventional ozonation method, the removal efficiency of nitrobenzene is increased by more than 60%, the removal efficiency of p-chlorobenzoic acid is increased by more than 85%, the removal efficiency of diethyl phthalate is increased by more than 90%, the removal efficiency of dibutyl phthalate is increased by more than 63%, and the removal efficiency of p-chloronitrobenzene is increased by more than 72%.
According to this embodiment, water after treatment is analyzed by a zinc ion analyzer and the test result shows that the water after treatment does not contain zinc ion. According to this embodiment, the ion dissolution problem does not exist and the water after treatment is clear and transparent with good sensory properties.
Embodiment 2
The embodiment 2 and the embodiment 1 have identical steps and parameters except that in the embodiment 2, the hydraulic retention time of the water subject to treatment in the ozone contact reactor is 30˜120 min.
Embodiment 3
The embodiment 3 and the embodiments 1 and 2 have identical steps and parameters except that in the embodiment 3, the metal zinc has a strip-like structure having a width of 1 cm˜10 cm and a thickness of 1 mm˜1 cm, and an amount of metal zinc is 10˜2000 g per liter of the water subject to treatment.
According to this embodiment, the catalyst is placed into the ozone contact reactor through a fixed-bed arrangement and is continuously or spacedly provided in the reactor.
Embodiment 4
The embodiment 4 and the embodiments 1 and 2 have identical steps and parameters except that in the embodiment 4, the metal zinc has a strip-like structure having a width of 1 cm˜10 cm and a thickness of 1 mm˜1 cm and is woven into a mesh structure having a grid size of 1 cm 2 ˜100 cm 2 , wherein an amount of metal zinc is 10˜2000 g per liter of the water subject to treatment.
According to this embodiment, the catalyst is placed into the ozone contact reactor through a fixed-bed arrangement and is continuously or spacedly provided in the reactor.
Embodiment 5
The embodiment 5 and the embodiments 1 and 2 have identical steps and parameters except that in the embodiment 5, the metal zinc has a thread-like structure having a diameter of 1 μm˜1 cm and is woven into a mesh structure having a grid size of 1 mm 2 ˜100 cm 2 , wherein an amount of metal zinc is 1˜1000 g per liter of the water subject to treatment.
According to this embodiment, the catalyst is placed into the ozone contact reactor through a fixed-bed arrangement and is continuously or spacedly provided in the reactor.
Embodiment 6
The embodiment 6 and the embodiments 1 and 2 have identical steps and parameters except that in the embodiment 6, the metal zinc has a granular structure having a grain size of 1 mm˜10 cm, wherein an amount of metal zinc is 1˜1000 g per liter of the water subject to treatment.
According to this embodiment, the catalyst is placed into the ozone contact reactor through a fixed-bed or a fluidized bed arrangement. When a fixed-bed arrangement is used, the catalyst is continuously or spacedly provided in the reactor.
Embodiment 7
The embodiment 7 and the embodiments 1 and 2 have identical steps and parameters except that in the embodiment 7, the metal zinc has a powder structure having a particle size of 10 μm˜1 mm, wherein an amount of metal zinc is 1 mg˜10 g per liter of the water subject to treatment.
According to this embodiment, the catalyst is placed into the ozone contact reactor through a fluidized bed arrangement. Through water flow and air flow control, the catalyst is maintained at a fluidized state. The catalyst can be recovered by precipitation or filtration.
Embodiment 8
The advanced treatment method for water by a combination of metal zinc and ozone according to this embodiment is realized by the following steps: placing metal zinc into an ozone contact reactor; and introducing water subject to treatment into the ozone contact reactor at a flow rate of 20 m/h while at the same introducing ozone to the water subject to treatment so that the ozone, the metal zinc and the water subject to treatment are contacted adequately, wherein a hydraulic retention time of the water subject to treatment in the ozone contact reactor is 30 min, an amount of the ozone which is introduced into the water subject to treatment is 10 mg per liter of the water subject to treatment, and the metal zinc has a strip-like structure having a width of 5 cm and a thickness of 0.5 cm.
According to this embodiment, the metal zinc is placed into the ozone contact reactor through a fixed-bed arrangement and is continuously provided in the reactor. The ozone contact reactor is a tubular reactor, a tank reactor or a tower reactor, wherein an amount of metal zinc is 1000 g per liter of the water subject to treatment.
According to this embodiment, the water subject to treatment is guided to flow into the reactor in a cocurrent manner, a countercurrent manner or a mixture of concurrent and countercurrent manner.
According to this embodiment, water after treatment is analyzed by a zinc ion analyzer and the test result shows that the water after treatment does not contain zinc ion. According to this embodiment, the ion dissolution problem does not exist and the water after treatment is clear and transparent with good sensory properties.
In the water subject to treatment of this embodiment, the nitrobenzene concentration is 0.8 mg/L, the p-chlorobenzoic acid concentration is 1 mg/L, the diethyl phthalate concentration is 0.5 mg/L, the dibutyl phthalate concentration is 0.65 mg/L and the p-chloronitrobenzene concentration is 0.89 mg/L. According to this embodiment, a removal efficiency of nitrobenzene is 98%, a removal efficiency of p-chlorobenzoic acid is 95.6%, a removal efficiency of diethyl phthalate is 98.9%, a removal efficiency of dibutyl phthalate is 96.8%, and a removal efficiency of p-chloronitrobenzene is 97.2%. The efficiency of advanced treatment method for water according to this embodiment is good. Compared to conventional ozonation method, the removal efficiency of nitrobenzene is increased by 69%, the removal efficiency of p-chlorobenzoic acid is increased by 87%, the removal efficiency of diethyl phthalate is increased by 99%, the removal efficiency of dibutyl phthalate is increased by 65%, and the removal efficiency of p-chloronitrobenzene is increased by 80%.
Embodiment 9
The advanced treatment method for water by a combination of metal zinc and ozone according to this embodiment is realized by the following steps: placing metal zinc into an ozone contact reactor; and introducing water subject to treatment into the ozone contact reactor at a flow rate of 30 m/h while at the same introducing ozone to the water subject to treatment so that the ozone, the metal zinc and the water subject to treatment are contacted adequately, wherein a hydraulic retention time of the water subject to treatment in the ozone contact reactor is 50 min, an amount of the ozone which is introduced into the water subject to treatment is 6 mg per liter of the water subject to treatment, and the metal zinc has a strip-like structure having a width of 1 cm and a thickness of 0.2 cm and is woven into a mesh structure having a grid size of 2 cm 2 .
According to this embodiment, the metal zinc is placed into the ozone contact reactor through a fixed-bed arrangement (spacedly provided at a vertical interval of 5 cm in the reactor). The ozone contact reactor is a tubular reactor, a tank reactor or a tower reactor, wherein an amount of metal zinc is 500 g per liter of the water subject to treatment.
According to this embodiment, the water subject to treatment is guided to flow into the reactor in a cocurrent manner, a countercurrent manner or a mixture of concurrent and countercurrent manner.
According to this embodiment, water after treatment is analyzed by a zinc ion analyzer and the test result shows that the water after treatment does not contain zinc ion. According to this embodiment, the ion dissolution problem does not exist and the water after treatment is clear and transparent with good sensory properties.
In the water subject to treatment of this embodiment, the nitrobenzene concentration is 0.2 mg/L, the p-chlorobenzoic acid concentration is 0.3 mg/L, the diethyl phthalate concentration is 0.2 mg/L, the dibutyl phthalate concentration is 0.1 mg/L and the p-chloronitrobenzene concentration is 0.2 mg/L. According to this embodiment, a removal efficiency of nitrobenzene, p-chlorobenzoic acid, diethyl phthalate, dibutyl phthalate and p-chloronitrobenzene from the water subject to treatment can reach 90% or above. The efficiency of advanced treatment method for water according to this embodiment is good.
Embodiment 10
The advanced treatment method for water by a combination of metal zinc and ozone according to this embodiment is realized by the following steps: placing metal zinc into an ozone contact reactor; and introducing water subject to treatment into the ozone contact reactor at a flow rate of 40 m/h while at the same introducing ozone to the water subject to treatment so that the ozone, the metal zinc and the water subject to treatment are contacted adequately, wherein a hydraulic retention time of the water subject to treatment in the ozone contact reactor is 30 min, an amount of the ozone which is introduced into the water subject to treatment is 4 mg per liter of the water subject to treatment, and the metal zinc has a thread-like structure having a diameter of 0.4 mm and is woven into a mesh structure having a grid size of 1 cm 2 .
According to this embodiment, the metal zinc is placed into the ozone contact reactor through a fixed-bed arrangement (continuous fixed-bed arrangement). The ozone contact reactor is a tank reactor.
According to this embodiment, the water subject to treatment is guided to flow into the reactor in a cocurrent manner, a countercurrent manner or a mixture of concurrent and countercurrent manner.
According to this embodiment, water after treatment is analyzed by a zinc ion analyzer and the test result shows that the water after treatment does not contain zinc ion. According to this embodiment, the ion dissolution problem does not exist and the water after treatment is clear and transparent with good sensory properties.
In the water subject to treatment of this embodiment, the nitrobenzene concentration is 0.12 mg/L, the p-chlorobenzoic acid concentration is 0.16 mg/L, the diethyl phthalate concentration is 0.18 mg/L, the dibutyl phthalate concentration is 0.22 mg/L and the p-chloronitrobenzene concentration is 0.15 mg/L. According to this embodiment, a removal efficiency of nitrobenzene is 96%, a removal efficiency of p-chlorobenzoic acid is 93%, a removal efficiency of diethyl phthalate is 98%, a removal efficiency of dibutyl phthalate is 94%, and a removal efficiency of p-chloronitrobenzene is 94%. The efficiency of advanced treatment method for water according to this embodiment is good. Compared to conventional ozonation method, the removal efficiency of nitrobenzene is increased by 70%, the removal efficiency of p-chlorobenzoic acid is increased by 82%, the removal efficiency of diethyl phthalate is increased by 92%, the removal efficiency of dibutyl phthalate is increased by 67%, and the removal efficiency of p-chloronitrobenzene is increased by 81%.
Embodiment 11
The advanced treatment method for water by a combination of metal zinc and ozone according to this embodiment is realized by the following steps: placing metal zinc into an ozone contact reactor; and introducing water subject to treatment into the ozone contact reactor at a flow rate of 45 m/h while at the same introducing ozone to the water subject to treatment so that the ozone, the metal zinc and the water subject to treatment are contacted adequately, wherein a hydraulic retention time of the water subject to treatment in the ozone contact reactor is 100 min, an amount of the ozone which is introduced into the water subject to treatment is 5 mg per liter of the water subject to treatment, and the metal zinc has a granular structure having a grain size of 1 cm, wherein an amount of metal zinc is 10˜1000 g per liter of the water subject to treatment.
According to this embodiment, the metal zinc is placed into the ozone contact reactor through a fixed-bed arrangement (continuous fixed-bed arrangement). The ozone contact reactor is a tank reactor.
According to this embodiment, the water subject to treatment is guided to flow into the reactor in a cocurrent manner, a countercurrent manner or a mixture of concurrent and countercurrent manner.
According to this embodiment, water after treatment is analyzed by a zinc ion analyzer and the test result shows that the water after treatment does not contain zinc ion. According to this embodiment, the ion dissolution problem does not exist and the water after treatment is clear and transparent with good sensory properties.
According to this embodiment, a removal efficiency of nitrobenzene, p-chlorobenzoic acid, diethyl phthalate, dibutyl phthalate and p-chloronitrobenzene from the water subject to treatment can reach 90% or above. The efficiency of advanced treatment method for water according to this embodiment is good. Compared to conventional ozonation method, the removal efficiency of nitrobenzene is increased by 69%, the removal efficiency of p-chlorobenzoic acid is increased by 87%, the removal efficiency of diethyl phthalate is increased by 95%, the removal efficiency of dibutyl phthalate is increased by 65%, and the removal efficiency of p-chloronitrobenzene is increased by 79%.
Embodiment 12
The embodiment 12 and the embodiment 11 have identical steps and parameters except that in the embodiment 12, an amount of metal zinc is 100˜900 g per liter of the water subject to treatment.
Embodiment 13
The embodiment 13 and the embodiment 11 have identical steps and parameters except that in the embodiment 13, an amount of metal zinc is 200˜800 g per liter of the water subject to treatment.
Embodiment 14
The embodiment 14 and the embodiment 11 have identical steps and parameters except that in the embodiment 14, an amount of metal zinc is 700 g per liter of the water subject to treatment.
According to this embodiment, the metal zinc is placed into the ozone contact reactor through a fixed-bed arrangement (spacedly provided at a horizontal interval of 10 cm). The ozone contact reactor is a tank reactor.
According to this embodiment, the water subject to treatment is guided to flow into the reactor in a countercurrent manner.
According to this embodiment, water after treatment is analyzed by a zinc ion analyzer and the test result shows that the water after treatment does not contain zinc ion. According to this embodiment, the ion dissolution problem does not exist and the water after treatment is clear and transparent with good sensory properties.
In the water subject to treatment of this embodiment, the nitrobenzene concentration is 0.96 mg/L, the p-chlorobenzoic acid concentration is 0.56 mg/L, the diethyl phthalate concentration is 1.1 mg/L, the dibutyl phthalate concentration is 0.22 mg/L and the p-chloronitrobenzene concentration is 0.45 mg/L. According to this embodiment, a removal efficiency of nitrobenzene is 96%, a removal efficiency of p-chlorobenzoic acid is 99%, a removal efficiency of diethyl phthalate is 97.6%, a removal efficiency of dibutyl phthalate is 98.9%, and a removal efficiency of p-chloronitrobenzene is 99.5%. The efficiency of advanced treatment method for water according to this embodiment is good. Compared to conventional ozonation method, the removal efficiency of nitrobenzene is increased by 69%, the removal efficiency of p-chlorobenzoic acid is increased by 86%, the removal efficiency of diethyl phthalate is increased by 93%, the removal efficiency of dibutyl phthalate is increased by 65%, and the removal efficiency of p-chloronitrobenzene is increased by 80%.
Embodiment 15
The embodiment 15 and the embodiment 11 have identical steps and parameters except that in the embodiment 15, the metal zinc has a granular structure having a grain size of 1 mm and an amount of metal zinc is 500 g per liter of the water subject to treatment.
According to this embodiment, the metal zinc is placed into the ozone contact reactor through a fluidized-bed arrangement, the ozone contact reactor is a tank reactor, the catalyst maintains its fluidized state by water and air flow control, the catalyst is recovered by precipitation or filtration.
According to this embodiment, the water subject to treatment is guided to flow into the reactor in a cocurrent manner.
According to this embodiment, water after treatment is analyzed by a zinc ion analyzer and the test result shows that the water after treatment does not contain zinc ion. According to this embodiment, the ion dissolution problem does not exist and the water after treatment is clear and transparent with good sensory properties.
In the water subject to treatment of this embodiment, the nitrobenzene concentration is 0.6 mg/L, the p-chlorobenzoic acid concentration is 0.3 mg/L, the diethyl phthalate concentration is 0.56 mg/L, the dibutyl phthalate concentration is 0.12 mg/L and the p-chloronitrobenzene concentration is 0.35 mg/L. According to this embodiment, a removal efficiency of nitrobenzene is 96%, a removal efficiency of p-chlorobenzoic acid is 97.9%, a removal efficiency of diethyl phthalate is 99.9%, a removal efficiency of dibutyl phthalate is 95.6%, and a removal efficiency of p-chloronitrobenzene is 96.8%. The efficiency of advanced treatment method for water according to this embodiment is good. Compared to conventional ozonation, method, the removal efficiency of nitrobenzene is increased by 70%, the removal efficiency of p-chlorobenzoic acid is increased by 84%, the removal efficiency of diethyl phthalate is increased by 93%, the removal efficiency of dibutyl phthalate is increased by 65%, and the removal efficiency of p-chloronitrobenzene is increased by 76%.
Embodiment 16
The advanced treatment method for water by a combination of metal zinc and ozone according to this embodiment is realized by the following steps: placing metal zinc into an ozone contact reactor; and introducing water subject to treatment into the ozone contact reactor at a flow rate of 35 m/h while at the same introducing ozone to the water subject to treatment so that the ozone, the metal zinc and the water subject to treatment are contacted adequately, wherein a hydraulic retention time of the water subject to treatment in the ozone contact reactor is 150 min, an amount of the ozone which is introduced into the water subject to treatment is 3 mg per liter of the water subject to treatment, the metal zinc has a powder structure having a particle size of 100 μm, and an amount of metal zinc is 1 mg˜10 g per liter of the water subject to treatment.
According to this embodiment, the catalyst is placed into the ozone contact reactor through a fluidized bed arrangement. Through water flow and air flow control, the catalyst is maintained at a fluidized state. The catalyst can be recovered by precipitation or filtration.
According to this embodiment, a removal efficiency of nitrobenzene, p-chlorobenzoic acid, diethyl phthalate, dibutyl phthalate and p-chloronitrobenzene from the water subject to treatment can reach 90% or above. The efficiency of advanced treatment method for water according to this embodiment is good. Compared to conventional ozonation method, the removal efficiency of nitrobenzene is increased by 69%, the removal efficiency of p-chlorobenzoic acid is increased by 87%, the removal efficiency of diethyl phthalate is increased by 99%, the removal efficiency of dibutyl phthalate is increased by 65%, and the removal efficiency of p-chloronitrobenzene is increased by 80%.
Embodiment 17
The embodiment 17 and the embodiment 16 have identical steps and parameters except that in the embodiment 17, an amount of metal zinc is 40˜900 mg per liter of the water subject to treatment.
Embodiment 18
The embodiment 18 and the embodiment 16 have identical steps and parameters except that in the embodiment 18, an amount of metal zinc is 50˜800 mg per liter of the water subject to treatment.
Embodiment 19
The embodiment 19 and the embodiment 16 have identical steps and parameters except that in the embodiment 19, an amount of metal zinc is 70 mg per liter of the water subject to treatment.
According to this embodiment, the water subject to treatment is guided to flow into the reactor in a mixture of concurrent and countercurrent manner. Through water flow and air flow control, the catalyst is maintained at a fluidized state. The catalyst can be recovered by precipitation or filtration.
In the water subject to treatment of this embodiment, the nitrobenzene concentration is 0.1 mg/L, the p-chlorobenzoic acid concentration is 0.1 mg/L, the diethyl phthalate concentration is 0.2 mg/L, the dibutyl phthalate concentration is 0.05 mg/L and the p-chloronitrobenzene concentration is 0.12 mg/L. According to this embodiment, a removal efficiency of nitrobenzene is 96.9%, a removal efficiency of p-chlorobenzoic acid is 99%, a removal efficiency of diethyl phthalate is 97.6%, a removal efficiency of dibutyl phthalate is 99.6%, and a removal efficiency of p-chloronitrobenzene is 94.8%. The efficiency of advanced treatment method for water according to this embodiment is good. Compared to conventional ozonation method, the removal efficiency of nitrobenzene is increased by 70%, the removal efficiency of p-chlorobenzoic acid is increased by 84%, the removal efficiency of diethyl phthalate is increased by 93%, the removal efficiency of dibutyl phthalate is increased by 65%, and the removal efficiency of p-chloronitrobenzene is increased by 76%.
Embodiment 20
The embodiment 20 and the embodiment 16 have identical steps and parameters except that in the embodiment 20, an amount of metal zinc is 500 mg per liter of the water subject to treatment.
According to this embodiment, the water subject to treatment is guided to flow into the reactor in a concurrent manner. Through water flow and air flow control, the catalyst is maintained at a fluidized state. The catalyst can be recovered by precipitation or filtration.
In the water subject to treatment of this embodiment, the nitrobenzene concentration is 0.24 mg/L, the p-chlorobenzoic acid concentration is 0.14 mg/L, the diethyl phthalate concentration is 0.25 mg/L, the dibutyl phthalate concentration is 0.11 mg/L and the p-chloronitrobenzene concentration is 0.06 mg/L. According to this embodiment, a removal efficiency of nitrobenzene is 97.6%, a removal efficiency of p-chlorobenzoic acid is 94.9%, a removal efficiency of diethyl phthalate is 98.7%, a removal efficiency of dibutyl phthalate is 92%, and a removal efficiency of p-chloronitrobenzene is 99%. The efficiency of advanced treatment method for water according to this embodiment is good. Compared to conventional ozonation method, the removal efficiency of nitrobenzene is increased by 71%, the removal efficiency of p-chlorobenzoic acid is increased by 85%, the removal efficiency of diethyl phthalate is increased by 95%, the removal efficiency of dibutyl phthalate is increased by 69%, and the removal efficiency of p-chloronitrobenzene is increased by 78%.
It will thus be seen that the objects of the present invention have been fully and effectively accomplished. It embodiments have been shown and described for the purposes of illustrating the functional and structural principles of the present invention and is subject to change without departure from such principles. Therefore, this invention includes all modifications encompassed within the spirit and scope of the following claims.
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An advanced treatment method of feed water by combination of metal zinc and ozone is provided. The advanced treatment method of feed water comprises putting metal zinc into an ozone contact reactor, adding water to be treated into the reactor at a flow rate of 1-50 m/h, at the same time, introducing ozone into the water such that the ozone, the metal zinc and the water can be contacted with each other fully. The hydraulic retention time of the water to be treated in the reactor is 1-200 min. The amount of the ozone which is introduced into the water to be treated is 0.1-100 mg per liter water. During the water treatment process of the invention, the metal ions cannot be lost, the secondary pollution cannot be caused, and the preparation technology is simple with low cost and good treatment effect.
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This application is a continuation of application Ser. No. 07/360,061 filed Jun. 1, 1989, now abandoned.
BACKGROUND OF THE INVENTION
Field of the Invention
The present invention relates to a data communication apparatus and method, and especially relates to a data communication apparatus and method which provide the ability to switch between data communication and voice communication.
Related Art
A conventional facsimile apparatus is used with a telephone to enable both voice communication and data communication.
In the case where one communication line is used for both the voice communication and the data communication, the facsimile apparatus is usually set in a manual receiving mode. When a call is received, an operator picks up and listens to a handset to make sure whether it is a person or a facsimile apparatus which is calling. If the calling station is a telephone, i.e., if a person is calling, the operator engages in conversation. If the calling station is a facsimile apparatus, the operator sets the apparatus to a data-communication mode.
Thus, in a conventional apparatus, the operator has to confirm whether it is a person or a facsimile apparatus calling. Especially, if the line is used with the facsimile apparatus more frequently than with the telephone, it is extremely inefficient.
SUMMARY OF THE INVENTION
A purpose of the present invention is to provide a data communication apparatus/method which overcomes the above-mentioned shortcomings.
According to one aspect of the present invention, a data communication apparatus and method are provided by means of which it is possible to discriminate whether voice communication or data communication is established when the call is received, by detecting noise on the communication line.
According to another aspect of the present invention, a data communication apparatus and method are provided in which a frequency of an input signal is measured by means of detecting a standard tonal-procedure signal which is used in data communication, and in which voice is detected by normalizing the detected tonal signal data, and which selects data communication or voice communication in accordance with whether the input signal from the calling station is a voice signal or not.
According to another aspect of the present invention, a data communication apparatus and method are provided which enable one to operate both a sending means for sending a procedure signal used in data communication and a discriminating means for discriminating whether the input signal is a voice signal or not, simultaneously.
The foregoing summary of certain advantageous features of the invention is provided in order that the detailed description of the preferred embodiments thereof that follows may be better understood, and in order that the present contribution to the art may be better appreciated. There are, or course, additional features of the invention that will be described in that detailed description with reference to the accompanying drawings. Those skilled in the art will appreciate that the conception upon which this disclosure is based may readily be utilized as a basis for designing other structures or methods for carrying out the purposes of the invention. It will be understood what the claims are to be regarded as including such other constructions and methods as do not depart from the spirit and scope of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram showing a structure of a facsimile apparatus according to a first preferred embodiment of the invention;
FIG. 2 is a block diagram showing a modified structure of the facsimile apparatus shown in FIG. 1;
FIG. 3 is a flow chart illustrating a control operation of a controller in the first embodiment;
FIG. 4 is a drawing showing a map of a RAM in the first embodiment;
FIGS. 5a and 5b are drawings showing examples of distribution of sampled frequency data by a tonal counter in the first embodiment;
FIG. 6 is a block diagram showing a structure of a facsimile apparatus according to a second preferred embodiment of the invention;
FIG. 7 is a flow chart illustrating a control operation of a controller in the second embodiment;
FIG. 8 is a block diagram showing a well known tonal counter; and
FIGS. 9a to 9f are timing charts showing a plurality of signal waveforms at various locations in the tonal counter.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The facsimile apparatus shown in FIG. 1 includes a control unit or controller 5 which is structured to have a micro-processor, and which controls the whole facsimile apparatus in accordance with a program stored in a ROM 2.
The controller 5 lets a communication unit 8 catch a line 11 and checks a procedure signal when a call is received. Then the controller 5 lets a tonal counter 9 receive a tonal signal. As a result, when the controller 5 recognizes that the calling station is a facsimile apparatus, the controller 5 encodes image data read by a reader 4 and transmits the coded image data via the communication unit 8, during a transmission operation, or receives the image data via the communication line 11 and the communication unit 8 and decodes the image data to be printed out by a recorder 6, during a receiving operation.
On the other hand, when the controller 5 recognizes that a person is on the line, the controller 5 activates a speaker 10, and makes a display unit 1 display a message, e.g., "PLEASE, ANSWER THE PHONE" to inform the operator of the called station that a person is calling to have a conversation.
The above-mentioned processes are explained more concretely as follows referring to the flow chart in FIG. 3 illustrating the control operation of the controller 5 of the first embodiment.
Initially, when the controller 5 of the called station detects a call signal on the line 11 via the communication unit 8, the controller 5 makes the communication unit 8 catch the line 11, and sets a receiving mode for receiving an input signal on the line 11 (S0).
In step S1, the controller 5 checks a binary procedure signal for a predetermined period. If the controller detects the binary procedure signal, the controller 5 processes the facsimile communication, because the calling station is a facsimile apparatus. Also in step S1, the controller 5 checks the tonal procedure signal and voice, which are detected by a tonal counter 9. The tonal counter 9, as well known, is structured as shown in FIG. 8. The input signal on the line 11 is input to input terminals 50, and is filtered by a low-pass filter 51. The input level of the signal is adjusted by an absolute level adjuster 52 and a variable level adjuster 53 to get a signal (a). The adjusted input signal (a) is digitized with a threshold level TH1 by a digitizer 54 to get a signal (b). The digitized signal (b) is input to a frequency counter 55 and a integrating circuit 56. The frequency counter 55 counts a number of sampling clocks falling in one period, shown a signal (c) of a frequency of the input signal. The counted number of sampling clocks is converted to a code, and then the code is output to the controller 5 as frequency data relating to the input signal.
The integrating circuit 56 integrates the digitized signal (b) to check whether energy is present on the line 11 or not. If the level of the input signal is extremely low, as shown in signal (f) (see FIG. 9), the output level of the integrating circuit 56 is low, and a binarizing circuit 57 outputs an inversion of a signal-energy-detect signal SDT, which is shown in FIG. 9 as signal (e).
As described above, the tonal counter 9 is structured to check the frequency of the input signal and the energy level on the line 11.
The frequency band from 300 Hz to 3.4 kHz of the input signal to be detected is divided into a plurality of areas. For example, a tonal procedure signal GC2, which is a command signal to command use of the G2 mode, has a frequency of 2100 Hz. Therefore, one divided frequency band is set from 2000 Hz to 2200 Hz by taking account of several conditions during transmission with error at the transmission side.
Counters corresponding to the divided areas respectively are set in a RAM 7 (see FIG. 1). The controller 5 discriminates which divided area the frequency data detected by the tonal counter 9 corresponds to, and the counter corresponding to the detected frequency data is incremented.
After the frequency data has been detected a predetermined number of times, or after a predetermined checking time is finished, the controller 5 discriminates whether the tonal procedure signal or a voice signal exists on the line 11 in accordance with a distribution state, or a histogram, of the detected frequency data.
FIG. 4 shows the structure of the counters in the RAM 7, and FIGS 5(a) and 5(b) shows examples of the frequency distribution. In FIGS. 4, 5(a) and 5(b), the magnitude relationships among a, b, c, d and n are a>b>c>d, and n<b-c. During the checking time, each time additional frequency data is obtained, the counter in the RAM 7 corresponding to the newly-obtained frequency data is incremented or decremented.
After the checking time is terminated, the contents of the counters in the RAM 7 are checked by the controller 5. If the frequency distribution is spread out, and the detected rate of one frequency area is lower than a predetermined rate, which detects a single tonal signal considering several conditions during transmission, as shown in FIG. 5(a), the controller 5 discriminates that the input signal on the line 11 represents a voice.
On the other hand, if the detected rate of one frequency area is higher than the predetermined rate which is the standard to detect the single tonal signal, as in FIG. 5(b), the controller 5 discriminates that the calling station is a facsimile apparatus, and performs data communication in response to the detection of the tonal procedure signal having the detected frequency component.
In this embodiment, count values of the counters corresponding to all the frequency areas are normalized with sums of all the count values as a population to detect the rate of the specified frequency data in step S5 in FIG. 3.
The bandwidth of each frequency area and the mentioned predetermined rate may be fixed, but it may instead be arranged that these values are set by means of a keyboard on an operation panel 3, by the operator.
As a result of the above-mentioned checking, if the level of signal energy on the line is low or no tonal signal is on the line during the checking period, the controller 5 moves to the facsimile-communication procedure because the controller 5 discriminates that the calling station is a facsimile apparatus and waits for response from the called station, in step S4.
In this embodiment, especially regarding step S4, if the controller 5 does not clearly decide whether the calling station is a facsimile apparatus or a telephone, the controller 5 gives priority to facsimile communication over voice communication.
If it is discriminated in step S4 that the tonal signal is detected during the checking time, the controller 5 checks the frequency distribution by normalizing the detected data in step S5 as mentioned above. In step S6, the controller 5 discriminates that a person is on the line at the calling station when a voice signal is detected, and discriminates that the calling station is a facsimile apparatus when the tonal procedure signal is detected.
Accordingly, if the controller 5 recognizes the tonal procedure signal, the controller 5 moves to facsimile-communication procedure, and if the controller 5 recognizes a voice signal, the controller 5 activates the speaker 10 or other device to output an appropriate sound, e.g., the ringing of a bell, and outputs the message "PLEASE, ANSWER THE PHONE" to the display unit 1 to be displayed to inform the operator that a person is on the line at the calling station in step S7.
Instead of the controller 5 activating the speaker 10, the controller 5 may activate a ringing signal generator 12 so that the bell (or the like) of a telephone 13 (see FIG. 2) rings, which achieves the effect of summoning the operator, even if the facsimile apparatus is some distance from the telephone 13.
Furthermore, if the controller 5 is unable to determine with certainty whether a facsimile apparatus or a person is on the line at the calling station, the controller 5 may cause the speaker 10 to output the signal on the line, to enable the operator to listen to that signal. Accordingly, the operator can discriminate the nature of the incoming signal even when the controller cannot do so. This reduces the possibility of error.
As mentioned above, the facsimile apparatus of the first embodiment checks the received signal on the line using the tonal counter, normalizes the frequency data, and discriminates automatically whether a facsimile apparatus or a person is on the line at the calling station. Accordingly, the operator need not pick up the handset of the telephone to check whether the calling station is a voice terminal or a facsimile terminal, every time a call is received. Therefore the communication line can be used more effectively, i.e., with less wasted time. Further, since the tonal counter, the speaker and the ringing signal generator are installed even in conventional facsimile apparatus, the cost of making a facsimile apparatus with the above-described operation is no higher than that of a conventional facsimile machine.
The explanation of a second embodiment is as follows:
FIG. 6 is a block diagram showing the structure of a facsimile apparatus of the second preferred embodiment. A control unit or controller 25 including a microprocessor is provided to control the whole apparatus according to a program stored in a ROM 22. When a call is received via a communication unit 28, the controller 25 causes the communication unit 28 to catch and keep a communication line 31, and the controller 25 lets the communication unit 28 transmit the facsimile procedure signal to the line 31 while the controller 25 checks the procedure signal and voice on the line 31. If neither a procedure signal nor a voice signal is detected during a predetermined time, the controller 25 causes the communication unit 28 to release the line 31, and the controller 25 goes back to a standby state.
If a procedure signal which shows that the calling station is in the receiving state is detected during the predetermined time, the controller 25 goes to a transmitting mode for transmitting image data. In the transmitting mode, the controller 25 causes a reader to read an original document which is to be sent, encodes the read image data, and transmits the coded image data to the calling station via the communication unit 28 and the line 31.
If a procedure signal which shows that the calling station is about to transmit image data is detected, the controller 25 causes the communication unit 28 to receive the image data, decodes the received image data, and lets a recorder 26 print the decoded image data.
If the voice of a person on the line is detected by voice detector 27, the controller 25 activates speaker 29, e.g., to produce a bell sound, and causes a display unit 21 to display the message "PLEASE, ANSWER THE PHONE". Thereby, the operator can be notified that a person is on the line at the calling station and wants a voice communication.
In this case, it is more effective that the facsimile apparatus inform the calling station that the line is connected both to a facsimile apparatus and to a telephone, by means of a voice response device 23.
A more concrete explanation is as follows, referring to FIG. 7.
When the controller 25 of the called station detects the calling signal, the controller 25 causes the communication unit 28 to catch and keep the communication line 31, to assume a receiving state, in step S11.
In step S12, the voice response device 23 generates a voice message, "This line is connected to a facsimile apparatus. In order to change to a telephone, please give your name. Thank you." This message is sent to the calling station via the communication unit 28 and the line 31.
Then the controller 25 checks the response signal from the calling station in steps S16 and S17 while the controller 25 causes the communication unit 28 to send facsimile procedure signals GI2 and DIS in step S15.
If no response from the calling station is detected in step S13 during a predetermined period, which is set by a timer T1 according to the CCITT recommendation T30, the controller 25 causes the communication unit 28 to release the line 31.
If, during the predetermined period, the controller 25 recognizes the facsimile procedure signal in step S16, the controller 25 immediately starts facsimile communication to process transmission or receiving of image data.
On the other hand, when a voice signal is detected by the voice detector 27 during the predetermined period, controller 25 causes the speaker 29 to ring the bell and causes the display unit 21 to display the message "PLEASE, ANSWER THE PHONE" (S18). Thereby, the operator of the called station can be informed that a person who wants voice communication is on the line at the calling station.
In the above embodiment, although the controller 25 causes the speaker to ring the bell to inform the operator that it is necessary to answer the phone, if a ringing signal generator for ringing the telephone as shown in FIG. 2 is installed, the same effect can be obtained even if the facsimile apparatus is apart from the telephone.
When the voice detector 27 is structured as a conventional tonal counter, and voice is checked for by a software control as described in the first embodiment, it is not necessary to install another circuit device for that purpose. Thereby, the apparatus need not be complicated and the cost of the apparatus does not increase, even though the facsimile apparatus has the described capabilities.
As mentioned above, the facsimile apparatus of the second embodiment is structured such that the communication line is seized by the facsimile apparatus at once, the facsimile procedure signals GI2 and DIS are transmitted while the facsimile procedure signal and voice signal are checked for, and the controller causes the facsimile communication to be performed when the calling station is a facsimile apparatus, and causes the bell to inform the operator of the need to answer the telephone when a person is on the line. As a result, the operator need not confirm, by picking up the handset, that a voice call is being received, every time a call comes in.
During the predetermined period set by the T1 timer, which in this embodiment is, e.g., 35±15 seconds, the controller 25 can check for the facsimile procedure signal and for a voice signal a plurality of times. As a result, the discrimination is carried out precisely and reliably, and since the apparatus has the voice response device, the operator at the calling station is not discountenanced by hearing a facsimile signal. Further, the T1 timer is used so that it is not necessary to install another timer, and the cost of the apparatus therefore does not increase.
The first and second preferred embodiments are explained above with reference to facsimile apparatus, by way of example. However, the present invention can be applied to other data communication apparatus, for example, teletex apparatus, personal computer communication devices, and word-processor communication devices.
As mentioned above, according to the present invention, one or more communication lines can be used effectively both for data communication and for voice communication, and whether a person, a voice terminal or a data-communication terminal is at the calling station is discriminated with a simple structure.
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A data communication apparatus/method discriminates whether a calling station is a data communication terminal or a voice terminal by sampling information on the communication line to obtain frequency data relating to that information, and summons an operator at the destination to let the operator answer when it is discriminated that the calling station is a voice terminal.
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[0001] This application claims benefit, under U.S.C. §119(a) of French National Application Number 03.03999, filed Apr. 1, 2003.
SUMMARY OF THE INVENTION
[0002] The invention relates to the use of alkoxyamines derived from β-phosphorylated nitroxides of formula (I):
in which A represents a hydroxyl radical, a radical R 1 O-in which R 1 represents a linear or branched alkyl residue with a number of carbon atoms ranging from 1 to 6; a radical MeO—in which Me represents an alkali metal such as Li, Na or K, an H 4 N +—, Bu 4 N +—or Bu 3 HN + — radical; a chlorine atom; R represents a hydrogen atom or a methyl radical; M is a free-radical-polymerizable vinyl monomer sequence; n is an integer that may be equal to 0; for the preparation of polymerized or non-polymerized mono- or polyalkoxyamines, of formula (II):
in which Z, which represents a mono- or polyfunctional structure, will be defined more fully later: x is an integer at least equal to one.
BACKGROUND OF THE INVENTION
[0005] European patent application EP 903 787 discloses alkoxyamines derived from β-phosphorylated nitroxides, which are used as free-radical polymerization initiators affording good polymerization control from (control of the masses, low polydispersities) in the case of numerous vinyl monomers: styrene and substituted styrenes, dienes, acrylic or methacrylic monomers, acrylonitrile.
[0006] The Applicant has found that reactive functions of ester type present on these alkoxyamines, and also derived functions such as an acid, acid salt or acid chloride function, allow chemical conversions to be performed easily either on the initial alkoxyamine or on the polymer derived from this alkoxyamine. The conversion of the initial alkoxyamine gives access to a novel alkoxyamine and allows the adaptation of the initiator to the intended application. In particular, this conversion may make it possible to synthesize polyalkoxyamines from a monoalkoxyamine. The conversion of the polymer derived from the alkoxyamine allows novel functional groups to be introduced or allows coupling reactions with another polymer. In particular, this conversion can give access to block copolymers involving blocks that are not available via free-radical polymerization.
SUMMARY OF THE INVENTION
[0007] One subject of the invention is thus the use of the alkoxyamines of formula (I):
in which A represents a hydroxyl radical, a radical R 1 O— in which R1 represents a linear or branched alkyl residue containing a number of carbon atoms ranging from 1 to 6; a radical MeO— in which Me represents an alkali metal such as Li, Na or K; an H4N +—, Bu 4 N +— or Bu 3 HN + — radical; a chlorine atom; R represents a hydrogen atom or a methyl radical; M is a free-radical-polymerizable vinyl monomer sequence; n is an integer that may be equal to 0; for the preparation of polymerized or non-polymerized mono- or polyalkoxyamines, of formula (II):
in which R and n have the same meaning as in formula (I); x is an integer at least equal to 1; Z represents a mono- or polyfunctional structure chosen from the structures given below in a non-limiting manner: CH 2 ═CH—CH 2 —O—, CH 2 ═CH—CH 2 —NH—, CH 3 —(OCH 2 CH 2 )p—O—, —O—(CH 2 )q—O—, p and q being integers at least equal to one, or more generally derived from compounds such as alcohols, polyols, amines, polyamines, epoxides, polyepoxides, esters, polyesters, amides, polyamides, imines, polyimines, polycarbonates, polyurethanes and silicones.
DETAILED DESCRIPTION OF THE INVENTION
[0010] As non-limiting examples of vinyl monomers M that may be used according to the present invention, mention will be made of styrene, substituted styrenes, dienes, acrylic monomers, for instance acrylic acid or alkyl acrylates, methacrylic monomers, for instance methacrylic acid or alkyl methacrylates, acrylonitrile, acrylamine and its derivatives, vinylpyrrolidinone or a mixture of at least two abovementioned monomers.
[0011] Alkoxyamines of formula (I) in which A represents a radical R 1 O— are known.
[0012] A subject of the invention is thus also the alkoxyamines of formula (I), with the exclusion of the alkoxyamines of formula (I) in which A represents a radical R 1 O—.
[0013] The compounds (I) in which A is OR 1 may be obtained according to a method described in European patent application EP 903 787.
[0014] The compounds in which A is OH and n=0 may be prepared according to methods known in the literature. The most common method involves the coupling of a carbon radical with a nitroxide radical. The method involving the ATRA (Atom Transfer Radical Addition) reaction, as described in French patent application 2 791 979 incorporated into the present text by reference, may be used.
[0015] This method consists in reacting a nitroxide of formula (III):
with a halogenated derivative of formula (IV):
in which X represents a chlorine atom or a bromine atom, R having the same meaning as in formula (I), in water-immiscible organic solvent medium in the presence of an organometallic system of formula Metal Y(L)r, in which the Metal is copper, Y represents a chlorine atom or a bromine atom,
L represents a ligand of the metal, and is chosen from polyamines such as:
tris[2-(dimethylamino)ethyl]amine:
N,N,N′,N′,N″-pentamethyldiethylenetriamine (PMDETA)
N,N,N′,N′-tetramethylethylenediamine:
(CH 3 ) 2 —N —CH 2 CH 2 —N—(CH3)2,
1,1,4,7,10,10-hexamethyltriethylenetetramine (HMTETA):
cyclic polyamines such as:
1,4,7-trimethyl-1,4,7-triazacyclononane, 1,5,9-trimethyl-1,5,9-triazacyclododecane, 1,4,8,11-tetramethyl-1,4,8,11-tetraazacyclotetradecane, by mixing together with stirring in the organic solvent a metal salt Metal-Y, the ligand L, the halogenated derivative (IV) and the nitroxide (III) in a (IV)/(III) molar ratio ranging from 1 to 1.4, and keeping the reaction medium stirred at a temperature of between 0° C. and 40° C. until the nitroxide (III) has completely disappeared, and then recovering the organic phase, which is washed with water, followed by isolating the alkoxyamine(I) by evaporating off the organic solvent under reduced pressure.
[0027] The organic solvent that will preferably be used is an aromatic hydrocarbon or a chlorinated derivative such as CH 2 Cl 2 .
[0028] The metal salt preferably used is CuBr.
[0029] CuBr (in which the copper is in oxidation state 1) and copper may also be introduced into the reaction medium.
[0030] The alkali metal salts of the alkoxyamines (I) (A=MeO—) may be readily obtained by dissolving, without heating, the alkoxyamine(I) in acid form in a minimum amount of methanol, followed by addition of 1.05 equivalents of alkali metal hydroxide in a minimum amount of water. The water/methanol mixture is evaporated off under reduced pressure and the remaining water is removed azeotropically with cyclohexane or benzene.
[0031] The compounds (I) in which A is Cl may be obtained by reacting compound (I) in which A is equal to OH with thionyl chloride.
[0032] The compounds (I) in which n=0 and R═H may be introduced as initiators-polymerization controllers to gain access to the compounds (I) in which n is other than 0.
[0033] The compounds of formula (II) may preferably be obtained via esterification, transesterification, amidation, transamidation and epoxide-opening reactions. It would not constitute a departure from the context of the invention if, for the esterification or amidation reactions, an intermediate acid chloride was used.
[0034] The esterification processes may in particular be used advantageously to prepare polyalkoxyamines from monoalkoxyamines.
[0035] The esterification and amidation processes may also be used advantageously to condense polymers that are not obtained via free-radical polymerization, for instance polyesters, polyamides or polyepoxides. These reactions thus allow access to a multitude of block copolymer structures, for instance polystyrene-polyester, polystyrene-polyamide, polystyrene-polyepoxide, polyacrylate-polyester, polyacrylate-polyamide or polyacrylate-polyepoxide.
[0036] By way of illustration, such reactions may be represented schematically as follows:
[0037] In general, to make a polymer reactive, a person skilled in the art generally uses either a free-radical grafting technique or a technique involving a functional initiator, for example of azo type. These techniques are not entirely satisfactory. The first method leads to a random distribution of the reactive functions on the chains. The second is limited by the initiation efficacy of the initiator used (which is not equal to 1) and by the fact that the initiated chains may become terminated by coupling or transfer (which gives rise to chains bearing 0, 1 or 2 functionalities).
[0038] The invention thus has in particular the advantage of producing and of using polymers whose chain-end functionality is fully controlled.
EXAMPLES
[0039] The examples that follow illustrate the invention in a non-limiting manner.
Example 1
Preparation of 2-[N-tert-butyl-N-(1-diethoxyphosphoryl-2,2-dimethylpropyl)aminoxy]propionic acid, referred to hereinbelow as AA-SG1 by hydrolysis of N-tert-butyl-N-1-diethylphophono-2,2-dimethylpropyl-O-1-methoxycarbonylethylhydroxylamine, referred to hereinbelow as MONAMS according to the reaction:
[0040]
[0041] MONAMS is prepared according to European patent application EP 903 787.
[0042] 3 g of MONAMS (7.9 mmol) dissolved in 45 ml of methanol are placed in a 100 ml round-bottomed flask. 0.4 g of sodium hydroxide (10 mmol) dissolved in 30 ml of water is added. The mixture is left to react at 50° C. for 24 hours. The reaction mixture is extracted with ether. The resulting aqueous phase is acidified to pH=2 with 5N HCl and then extracted with dichloromethane. The organic phase is evaporated under vacuum to give 2.6 g of the acid form of the alkoxyamine referred to as AA-SG1 in the form of a white powder (yield=90%).
Characterization of 2-[N-tert-butyl-N-(1-diethoxyphosphoryl-2,2-dimethylpropyl)-aminoxy]propionic acid
[0043]
m.p.=145° C.
31 P NMR (121.59 MHz, CDCl 3 ):□27.65 (s, Dia I, 65%). 24.60 (s, Dia II, 35%).
1 H NMR (300 MHz, CDCl 3 ): Dia I. □4.68 (q, J=6 Hz, 1H), 3.90-4.35 (m, 4H), 3.38 (d, J=27 Hz, 1H), 1.61 (d, J=6 Hz, 3H), 1.34 (m, 6H), 1.20 (s, 9H), 1.19 (s, 9H). Dia II. □4.54 (q, J=9 Hz, 1H), 3.90-4.35 (m, 4H), 3.38 (d, J=27 Hz, 1H), 1.49 (d, J=9 Hz, 3H), 1.31 (t, J=9 Hz, 6H), 1.17 (s, 9H), 1.12 (s, 9H).
13 C NMR (75.54 MHz, CDCl 3 ): Dia I. □174.17 (s, C OOH), 81.46 (s, C H—O), 68.12 (d, J=139 Hz, C H—P), 62.53 (s, N— C (CH 3 ) 3 ), 62.65 (d, J=5.28 Hz, CH 2 ), 59.86 (d, J=7.55 Hz, CH 2 ), 35.54 (d, J=4.53 Hz, CH— C (CH 3 ) 3 ), 30.24 (d, J=6.8 Hz, CH—C( C H 3 ) 3 ), 27.80 (s, N—C( C H 3 ) 3 ), 19.35 (s, CH— C H 3 ), 16.31 (d, J=5.29 Hz, CH 2 C H 3 ), 16.04 (d, J=6.8 Hz, CH 2 C H 3 ). Dia II. □174.78 (s, C OOH), 81.31 (s, C H—O), 69.47 (d, J=141.26 Hz, C H—P), 62.53 (s, N— C (CH 3 ) 3 ), 62.22 (d, J=6.8 Hz, CH 2 ), 59.86 (d, J=7.55 Hz, CH 2 ), 35.59 (d, J=2.26 Hz, CH— C (CH 3 ) 3 ), 29.85 (d, J=6.04 Hz, CH—C(CH 3 ) 3 ), 27.72 (s, N—C(H 3 ) 3 ), 18.43 (s, CH— C H 3 ), 16.35 (d, J=6.8 Hz, CH 2 C H 3 ), 16.13 (d, J=6.8 Hz, CH 2 ! C H 3 ).
Example 2
Esterification of AA-SG1
[0047]
[0048] 2 g of AA-SG1 (5.4 mmol) dissolved in 25 ml of dichloromethane predried over molecular sieves are placed in a 100 ml round-bottomed flask under a nitrogen atmosphere. 1.9 g of thionyl chloride (16.2 mmol) are added and the mixture is left to react for 45 minutes at room temperature. The reaction mixture is evaporated under vacuum to give the acid chloride of the alkoxyamine in the form of an oil, which is used in the subsequent synthesis without further purification.
[0049] The acid chloride obtained above is redissolved in 30 ml of ethyl ether (predried by distillation over sodium-benzophenone). A mixture containing 0.62 g of allyl alcohol (10.8 mmol), 0.55 g of triethylamine (5.4 mmol), 0.13 g of 4-dimethylaminopyridine (1.1 mmol) and 10 ml of ether is added thereto at room temperature. The mixture is left to react for 2 hours at room temperature. The reaction mixture is filtered, washed with aqueous 0.1 M HCl solution and then washed with aqueous 5% potassium bicarbonate solution. The organic phase is evaporated to give 1.53 g of the allylic amide of the alkoxyamine AA-SG1 (yield=60%).
Characterization of allyl 2-[N-tert-butyl-N-(1-diethoxnihosphoryl-2,2-dimethylpropyl)-aminoxy]propionate
[0050]
31 P NMR (121.59 MHz, CDCl 3 ): □23.23 (s, Dia I, 80%). 22.61 (s, Dia II, 20%).
1 H NMR (300 MHz, CDCl 3 ): □5.96-5.87 (m, 2H, dia I+II), 5.37-5.23 (m, 4H, dia I+II), 4.64-4.58 (m, 6H, dia I+II), 4.25-3.93 (m, 8H, dia I+II), 3.37 (d, J=27 Hz, 1H, dia II), 3.27 (d, J=24 Hz, dia I), 1.53 (d, J=9 Hz, 3H, dia I), 1.50 (d, J=6 Hz, 3H, dia II), 1.36-1.27 (m, 12H, dia I+II), 1.17 (s, 9H, dia II), 1.16 (s, 9H, dia I), 1.14 (s, 9H, dia II), 1.11 (s, 9H, dia I).
13 C NMR (75.54 MHz, CDCl 3 ): Dia I. □173.43 (s, C O), 131.69 (s, C H═CH 2 ), 118.50 (s, CH═ C H 2 ), 82.49 (s, C H—ON), 69.51 (d, J=139.75 Hz, C H—P), 64.90 (s, O— C H 2 — C H), 61.71 (d, J=6.04 Hz, CH 2 ), 61.52 (s, N— C (CH 3 ) 3 ), 58.67 (d, J=7.55 Hz, CH 2 ), 35.45 (d, J=5.28 Hz, CH— C (CH 3 ) 3 ), 29.46 (d, J=5.28 Hz, CH—C( C H 3 ) 3 ), 27.81 (s, N—C( C H 3 ) 3 ), 19.19 (s, CH— C H 3 ), 16.40 (d, J=5.29 Hz, CH 2 C H 3 ), 16.10 (d, J=6.8 Hz, CH2 C H 3 ). Dia II. □172.03 (s, C O), 132.06 (s, CH═ C H 2 ), 117.97 (s, CH═ C H 2 ), 82.49 (s, C H—ON).69.17 (d, J=139.75 Hz, C H—P), 64.83 (s, O—CH 2 —CH), 61.81 (d, J=8.3 Hz, CH 2 ), 61.27 (s, N— C (CH 3 ) 3 ), 58.82 (d, J=6.8 Hz, CH 2 ), 35.10 (d, J=5.28 Hz, CH— C (CH 3 ) 3 ), 30.17 (d, J=6.04 Hz, CH—C( C H 3 ) 3 ), 27.87 (s, N—C( C H 3 ) 3 ), 17.73 (s, CH— C H 3 ), 15.80 (d, J=6.8 Hz, CH 2 C H 3 ), 15.77 (d, J=6.8 Hz, CH 2 C H 3 ).
Example 3
Amidation of AA-SG1
[0053]
[0054] The acid chloride of the alkoxyamine AA-SG1 is synthesized in the same manner as in Example 2.
[0055] 2.1 g of acid chloride (5.4 mmol) are dissolved in 30 ml of ethyl ether. A mixture containing 0.62 g of allylamine (10.8 mmol), 0.55 g of triethylamine (5.4 mmol), 0.13 g of 4-dimethylaminopyridine (1.1 mmol) and 10 ml of ether is added at room temperature. The mixture is left to react for two hours at room temperature. The reaction mixture is filtered, washed with aqueous 0.1 M HCl solution and then washed with aqueous 5% potassium bicarbonate solution. The organic phase is evaporated to give 1.53 g of the allylic amide of the alkoxyamine AA-SG1 (yield=70%).
Characterization of N-allyl-2-[N-tert-butyl-N-(1-diethoxyphosphoryl-2,2-dimethyl-propyl)aminoxy]propionamide
[0056]
31 P NMR (121.59 MHz, CDCl 3 ): □27.42 (s, Dia I, 35%). 27.05 (s, Dia II, 65%).
1 H NMR (300 MHz, CDCl 3 ): Dia I □8.61 (b, NH, 1H), 5.96-5.83 (m, 1H), 5.19 (dq, J HH =1.5 Hz, J HH =18 Hz, 1H), 5.08 (dq, J HH =1.5 Hz, J HH =9 Hz, 1H), 4.48 (q, J=6 Hz, 1H), 4.29-3.97 (m, 5H), 3.67 (m, 1H), 3.35 (d, J=27 Hz), 1.51 (d, J=6 Hz, 3H), 1.35-1.28 (m, 6H), 1.21 (s, 9H), 1.08 (s, 9H). Dia II. 7.74 (b, NH, 1H), 5.96-5.83 (m, 1H), 5.21 (d, J=18 Hz, 1H), 205.11 (d, J=9 Hz, 1H), 4.51 (q, J=9 Hz, 1H), 4.20-3.95 (m, 5H), 3.88 (t, J=7.5 Hz, 1H), 3.28 (d, J=24 Hz), 1.63 (d, J=6 Hz, 3H), 1.36-1.28 (m, 6H), 1.25 (s, 9H), 1.24 (s, 9H).
13 C NMR (75.54 MHz, CDCl 3 ): Dia I. □173.55 (s, C O), 134.40 (s, C H═CH 2 ), 115.18 (s, CH═ C H 2 ), 81.76 (s, C H—ON), 68.56 (d, J=137.48 Hz, C H—P), 62.17 (s, N— C (CH 3 ) 3 ), 61.56 (d, J=6.04 Hz, CH 2 ), 59.64 (d, J=7.55 Hz, CH 2 ), 41.06 (s, N—CH 2 ), 35.36 (d, J=5.28 Hz, CH— C (CH 3 ) 3 ), 29.69 (d, J=6.04 Hz, CH—C(CH 3 ) 3 ), 28.15 (s, N—C(CH 3 ) 3 ), 19.21 (s, CH— C H 3 ), 16.25 (d, J=6.04 Hz, CH 2 C H 3 ), 15.91 (d, J=6.8 Hz, CH 2 C H 3 ). Dia II. □173.42 (s, C O), 134.27 (s, C H═CH 2 ), 116.30 (s, CH═ C H 2 ), 83.05 (s, C H—ON), 69.25 (d, J=137.48 Hz, C H—P), 62.85 (s, N— C (CH 3 ) 3 ), 61.55 (d, J=6.04 Hz, CH 2 ), 60.04 (d, J=7.55 Hz, CH 2 ), 41.46 (s, N—CH 2 ), 35.33 (d, J=5.28 Hz, CH— C (CH 3 ) 3 ), 30.06 (d, J=5.28 Hz, CH—C( C H 3 ) 3 ), 28.38 (s, N—C( C H 3 ) 3 ), 19.55 (s, CH— C H 3 ), 16.55 (d, J=6.80 Hz, CH 2 CH 3 ), 16.30 (d, J=6.8 Hz, CH 2 C H 3 ).
Example 4
Preparation of the alkoxyamine 2-methyl-2 [N-tert-butyl-N-(1-diethoxyphosphoryl-2,2-dimethylpropyl)aminoxy]propionic acid) referred to as methylpropionic acid-SG1
[0059]
Procedure:
[0061] 500 ml of degassed toluene, 35.9 g of CuBr (250 mmol), 15.9 g of copper powder (250 mmol) and 86.7 g of N,N,N′,N′,N″-pentamethyldiethylenetriamine-PMDETA-(500 mmol) are introduced into a 2 l glass reactor purged with nitrogen, followed by introduction, with stirring and at room temperature (20° C.), of a mixture (a solution) containing 500 ml of degassed toluene, 42.1 g of 2-bromo-2-methylpropionic acid (250 mmol) and 78.9 g of 84% SG1, i.e. 225 mmol.
[0062] The mixture is left to react for 90 minutes at room temperature and with stirring, and the reaction medium is then filtered. The toluene filtrate is washed twice with 1.5 l of saturated aqueous NH 4 Cl solution.
[0063] A yellowish solid is obtained, which is washed with pentane to give 51 g of N-tert-butyl-N-1-diethylphosphono-2,2-dimethylpropyl-O-1-carboxymethylethylhydroxyl-amine (yield=60%).
[0064] The analytical results are given below:
molar mass determined by mass spectrometry: 381.44/g.mol −1 (for C 17 H 36 NO 6 P) elemental analysis (empirical formula: C 17 H 36 NO 6 P) % calculated: C=53.53, H=9.51, N=3.67 % found: C=53.57, H=9.28, N=3.77 melting performed on Büchi B-540 apparatus: 124-125° C.
31 p NMR (CDCl 3 ): δ 27.7 1 H NMR (CDCl 3 ):
δ 1.15 (singlet, 9H on carbons 15, 21 and 22), δ 1.24 (singlet, 9H on carbons 17, 23 and 24), δ 1.33-1.36 (multiplet, 6H on carbons 4 and 7), δ 1.61 (multiplet, 3H on carbon 18), δ 1.78 (multiplet, 3H on carbon 13), δ 3.41 (doublet, 1H on carbon 9), δ 3.98-4.98 (multiplet, 4H on carbons 3 and 6) δ 11.8 (singlet —O H ).
[0080] 13 C NMR (CDCl 3 ):
Carbon atoms No. δ 3 and 6 60.28-63.32 9 69.86 12 63 13 28.51 14 36.04 15, 21 and 22 29.75 16 63.31 17, 23 and 24 28.74 18 24.08 19 176.70
Example 5
Synthesis of a dialkoxyamine from the alkoxyamine methylpropionic acid-SG1
[0081]
[0082] The alkoxyamine methylpropionic acid-SG1 is prepared according to Example 4.
[0083] 10 g of alkoxyamine methylpropionic acid-SG1 (26 mmol) and 50 ml of dichloromethane (dried over calcium hydride) are introduced into a 250 ml reactor purged with nitrogen. 6.2 g of SOCl 2 (52 mmol) are added, via a dropping funnel, at room temperature. The mixture is left to react for 2 hours at room temperature with stirring and under a gentle stream of nitrogen. Evaporation under vacuum is performed to remove the excess SOCl 2 and the solvent. The acid chloride of the alkoxyamine is obtained, and is used in the subsequent synthesis without further purification.
[0084] The resulting oil is redissolved in 50 ml of dry dichloromethane. A mixture containing 1.2 g of 1,4-butanediol (13 mmol), 2.6 g of triethylamine (26 mmol) and 0.3 g of 4-dimethylaminopyridine (2.6 mmol) dissolved in 10 ml of dichloromethane is placed in the dropping funnel, under a nitrogen atmosphere. The above mixture is added dropwise to the reactor and the mixture is then left to react for three hours at room temperature. The reaction mixture is filtered, washed with a KHCO 3 solution and then washed with water. The organic phase is recovered, dried over magnesium sulphate and evaporated to dryness under vacuum at room temperature. A solid is obtained, which is washed with cold pentane to give 5.2 g of dialkoxyamine (yield=50%).
[0085] The dialkoxyamine was characterized by proton, carbon-13 and phosphorus NMR. 31 P NMR (CDCl 3 ): δ=26 ppm.
Example 6
Coupling Between the alkoxyamine methylpropionic Acid-SG1 and a POE-Ome Block (Mn=750 g.mol −1 )
[0086]
[0087] The alkoxyamine methylpropionic acid-SG1 (1 equivalent), the α-methoxylated poly(ethylene oxide) (1 equivalent) and 4-dimethylaminopyridine (DMAP) (1 equivalent) are placed in anhydrous dichloromethane in a round-bottomed flask equipped with a magnetic stirrer and a condenser. The solution is degassed by sparging with nitrogen for 10 to 15 minutes. Dicyclohexylcarbodiimide (DCC) (2.6 equivalents), dissolved in a minimum amount of dichloromethane, is added to the mixture via a syringe. The mixture is stirred for three hours at 0° C. The residual POE-OMe is removed by selective precipitation from ethanol. The filtrate is evaporated under vacuum. The degree of coupling, determined by proton NMR, is 37%.
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The invention relates to the use of alkoxyamines of formula (I):
for the preparation of polymerized or non-polymerized mono- or polyalkoxyamines of formula (II):
| 2
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RELATED APPLICATIONS
[0001] This is a continuation-in-part of U.S. patent application Ser. No. 10/731,264, filed Dec. 9, 2003, pending, which is a continuation of U.S. patent application Ser. No. 10/086,285, filed Mar. 1, 2002, now U.S. Pat. No. 6,662,574, which claims domestic priority from U.S. Provisional Patent Application No. 60/272,510 filed Mar. 1, 2001. All of the teachings of the foregoing applications are incorporated by reference herein.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] This invention relates to devices for use in the rapid cooling of fluids in various containers of differing geometry, and more particularly to such devices in communication with freezer units, refrigerator-freezers, and the like.
[0004] 2. Description of the Related Art
[0005] Various devices and methods have been employed in cooling beverages or fluids in containers from room temperature to consumption-pleasing low temperatures (or other desirable storage-type low temperatures), generally of about 5° C. The most common method is the use of commercial or household refrigerators or freezer units into which the beverage containers are statically placed. Air inside the conventional refrigerator or freezer is cooled, and the air cools the beverages or fluids. While effective, such cooling means entails the utilization of massive refrigerator and freezer space (especially in commercial establishments) which is costly and is at a premium, particularly when freezer or refrigerator space is generally required for other food storage purposes.
[0006] In addition to occupying a lot of space, these conventional refrigeration and freezer units require inordinate initial periods of time to cool a liquid such as a beverage, for example, from room temperature (20°-25° C.) to the desired 5° C., approximately an hour to several hours. If reasonably immediate consumption is required, such as at point of sale, at parties, or on very hot days, this time delay for cooling is unacceptable. Also, many individuals prefer beverages at temperatures colder than a conventional refrigerator can provide, e.g., 1-2° C. (or even at colder temperatures, as beer can be chilled down to −5° C.).
[0007] Accordingly, quick cooling devices have been developed specifically for use with beverage containers. Some of these devices, while generally effective in reducing the time for cooling beverages, nevertheless still require a minimum of about five minutes for the cooling of a standard 12 oz aluminum beverage can, still an inordinate amount of waiting time for a customer; this cooling lag time increases for larger containers, such as 16 oz or 20 oz soda or beer bottles and roughly 25 oz wine bottles.
[0008] Existing cooling devices operate on one of two general methods involving heat transfer. A first method involves cooling with ice such as embodied in a commercial device known as the Chill Wizzard and as described in U.S. Pat. No. 4,580,405 to Cretemeyer, III. This device provides for placement of a beverage can on a bed of ice to effect heat transfer and cooling. Since only a portion of the container is in contact with the ice, the container is rotated against the ice. In order to rotate the device, a suction cup connected to the spindle of a motor is attached to the bottom of the can. In addition, in order to maintain heat transfer-contact with the ice, the device provides for a constant mechanically-exerted contact pressure of the container against the ice to compensate for the melting and consequent reduction of height of the ice. Since ice can have substantially lower temperatures than the desired drinking temperature, heat exchange and beverage temperature lowering is facilitated and hastened. However, the Chill Wizzard device can only chill 12 oz cans and is unable to accommodate a variety of different-sized or -shaped containers. Further problems with this method are discussed below.
[0009] A second, less effective method involves conveying or placing the beverage containers into a cold water or bath. Because the container is stationary, cooling times for this method have been substantially longer than that for methods which utilize horizontal rotation of the container. This is also true because the water is stationary as well.
[0010] Another commercial device is the Vin Chilla (and similar products made by Breville and Salton), a bucket-shaped device for cooling wine bottles. A bottle is placed upright in the bucket and ice and water are added thereto. The device swirls the water around the bottle. Although the Vin Chilla commercial literature claims it can chill wine to a drinkable temperature in about 4 minutes, this period is only valid for cooling red wines, which are to be consumed at only 1-2 degrees below room temperature. A white wine requires up to 20 minutes of cooling to be brought to a desirable temperature, e.g., 5° C.
[0011] Despite its effectiveness in cooling (because of its low temperatures relative to water), the use of ice as a direct cooling medium can however be detrimental in certain common uses. When used for cooling carbonated beverages, particularly when such cooling is not carefully monitored, freezing of the beverage, with untoward consequences (i.e., the rupturing of the container and spilling of its contents), is possible. Specifically, the temperature of ice is rarely at 0° C. and is usually significantly lower. As a result, if the ice temperature is sufficiently low, freezing of the beverage within the container is possible, especially with extended cooling times. Since such containers are closed, it is difficult if not impossible to monitor temperature and phase conditions of the beverage during the cooling process to stop the process prior to any freezing. Under these conditions, with excessive cooling, partially frozen carbonated beverages will erupt when the container is opened. Though cold water is not subject to this detrimental effect with carbonated beverages, its use is however not as efficient in effecting the requisite rapid cooling.
[0012] One major improvement in this field of endeavor is described in U.S. Pat. No. 5,505,054 to Loibl et al., the same inventors as the instant inventors and which patent is assigned to the same entity to which the instant invention is assigned. Loibl et al. teach an extremely rapid method and device for cooling beverages. One or more beverage containers are rapidly rotated substantially along their respective longitudinal axes while being downwardly sprayed with a cooling water spray, with the water being recycled from a 0° C. ice water bath. The volumetric rate of the water in the water spray is sufficient to form a continuous coating on the rotating container. Rotation of the containers is effected in a horizontal direction, with the containers being nested between adjacent rotating rollers and rotated with a speed of between 200-500 rpm. Standard 12 oz. beverage cans can be cooled thereby from room temperature to a drinking temperature of 5° C. in under one minute. The teachings of the Loibl patent are herein incorporated by reference, particularly col. 2, line 55-col. 5, line 58.
[0013] Yet the prior Loibl device, while extremely effective, incorporates a number of spray jets positioned in various locations above the rotating containers and a number of rollers positioned below the containers. It is desirable to simplify this design. Moreover, it is desired to be able to incorporate the basic principles of Loibl '054 within a household refrigerator-freezer or freezer unit. One of the drawbacks of the original Loibl device is that it is a tabletop device or otherwise stand-alone device that requires a replenishible source of ice. It would be advantageous to incorporate the Loibl device into a refrigerator and take advantage of a cooling device that is already present in almost every home.
SUMMARY OF THE INVENTION
[0014] It is an object of the present invention to provide a means for the very rapid cooling of liquids such as beverages within containers, with a time period of cooling which is significantly shorter than that of prior art devices which utilize cooling with ice.
[0015] It is another object of the present invention to provide a rapid cooling device which is safe, easily manufactured, and appropriate for a fairly unsophisticated consumer/retail market.
[0016] It is another object of the present invention to provide a rapid cooling device without the detriment of possible freezing of carbonated beverages.
[0017] It is another object of the invention to provide a single, simple-to-use control system for cooling a beverage or other fluid within a container.
[0018] It is another object of the invention to provide a rapid cooling system as part of a refrigerator-freezer or -freezer unit.
[0019] The above and other objects are fulfilled by the invention, which is an apparatus for rapidly cooling a liquid in a container in a freezer or refrigerator-freezer unit. A housing is provided having a bottom and side walls defining an interior volume adapted to receive a container of liquid. A rotating mechanism is disposed in the housing adapted to rotate a container about the container's longitudinal axis. A source of a cooling medium is provided to cool the container, and a chilling means is provided to chill the cooling medium. When the container is placed within the interior volume, the cooling medium thermally communicates with the container while the rotating mechanism rotates the container.
[0020] The chilling means preferably includes at least one ice tray having an inlet receiving the cooling medium, a chilling surface in thermal communication with the freezer compartment and receiving the cooling medium from the inlet, and an outlet allowing the cooling medium to exit the ice tray. Preferably, the ice tray includes a plurality of stages having chilling surfaces disposed one atop another, wherein the cooling medium passes over each of the chilling surfaces one after another. In one embodiment, water is introduced above the top stage and flows downward to a lower stage in a cascading fashion. In another embodiment, water is pumped up from beneath the lowest stage and moves upward over succeeding upper stages.
[0021] The inventive apparatus preferably further includes a reservoir for storing the cooling medium and maintaining the cooling medium substantially at a given temperature. In one embodiment, the reservoir preferably has a reservoir inlet communicating with the ice tray outlet and a reservoir outlet communicating to the cooling medium source. The housing empties cooling medium into the ice tray inlet.
[0022] Insulation is preferably provided around the various portions of the apparatus. A first section of insulation preferably substantially insulates the housing from the freezer compartment, a second section of insulation preferably substantially insulates the ice tray from ambient air, and a third section of insulation is provided in two parts, a first part that partially insulates the reservoir from the freezer compartment and a second part that partially insulates the reservoir from ambient air. The first and second parts of the third section of insulation are adapted to keep the reservoir substantially as cold as possible without completely freezing the cooling medium.
[0023] Turning to some optional specifics of the ice tray, the ice tray further includes a pair of side walls; each of the stages may be attached to one of the side walls in a cantilever manner having a fixed end and a free end. In this embodiment, a free end of a given stage is disposed above a fixed end of the stage immediately therebelow. Preferably, a lip is disposed on the free end of each of the stages. In embodiments in which the cooling medium flows downward via gravity in the ice tray, the lip is a raised lip. In embodiments in which the cooling medium is pumped upward, the lip may be raised or downwardly projecting, or both. Each of the chilling surfaces may be angled away from its respective side wall, particularly in the downward flowing ice tray. Alternatively, each stage may be fixed to both side walls at both ends and provided with through holes which allow the cooling medium to reach the next stage. Posts or small protrusions may preferably project from the chilling surfaces to create turbulence within the fluid flow.
[0024] The housing may be disposed on or as a part of the door of the freezer, as may the reservoir and/or the ice tray. At least one fin may be provided projecting into either the ice tray or the reservoir (or both) in thermal communication with the freezer compartment.
[0025] The inventive apparatus may employ both ice tray and reservoir, or only a reservoir, or only an ice tray, depending on the thermal properties of the cooling medium, the temperature of the freezer, and a variety of other factors.
[0026] The invention also includes a freezer incorporating any of the embodiments of inventive apparatus described above.
[0027] The invention also includes an apparatus for rapidly cooling a liquid in a container as part of a domestic cooling device having a compressor and at least two cooling compartments, one compartment being colder than the other warmer compartment. The apparatus includes a housing having an interior volume adapted to receive a container, the housing being disposed in one of the two compartments. A rotating mechanism is disposed in the housing adapted to rotate a container placed in the housing about the container's longitudinal axis. A source of a cooling medium is provided to cool the container in the housing. At least one ice tray is disposed in either cooling compartment having a chilling surface in thermal communication with the colder compartment adapted to chill the cooling medium. The apparatus also preferably includes a reservoir disposed in either compartment and in thermal communication with the colder compartment adapted to substantially maintain the cooling medium at a given temperature. The cooling medium recirculates among the housing, the ice tray, and the reservoir. Preferably, at least one fin projects into the reservoir and is in thermal communication with the colder compartment or, alternatively, directly with the evaporator of the domestic cooling device. Optionally, the ice tray acts as a shelf in its compartment upon which items (such as food) may be placed.
[0028] In one embodiment, the housing is disposed in the warmer compartment, and includes a housing outlet. Here, the ice tray may be disposed in the warmer compartment and may include: a fin projecting into the colder compartment; an ice tray inlet communicating with the housing outlet; and an ice tray outlet. In this embodiment, the reservoir includes a reservoir inlet communicating with the ice tray outlet and a reservoir outlet communicating with the cooling medium source in the housing. The ice tray may include baffles, projecting from the chilling surface, adapted to direct flow of the cooling medium across the chilling surface. The baffles encourage the cooling medium to spread substantially over the chilling surface before draining out of the ice tray via the ice tray outlet.
[0029] In another embodiment, the housing is disposed in the colder compartment and has a housing outlet (drain). Here, the ice tray may be disposed in the colder compartment and may include: an ice tray outlet in communication with the cooling medium source in the housing; and an ice tray inlet. The reservoir includes a reservoir inlet in communication with the housing outlet and a reservoir outlet in communication with the ice tray inlet. A supplemental ice tray may optionally be disposed between the housing outlet and the reservoir inlet, or in between any of the components in any of the embodiments.
[0030] In another embodiment, the housing may again be disposed in the colder compartment and have a housing outlet (drain). Here, the ice tray is disposed in the colder compartment and includes: an ice tray inlet in communication with the housing outlet; and an ice tray outlet. The reservoir includes a reservoir inlet in communication with the ice tray outlet and a reservoir outlet in communication with the cooling medium source in the housing. A supplemental ice tray may optionally be disposed between the reservoir outlet and the cooling medium source in the housing.
[0031] In all of the above embodiments, the ice tray may include a plurality of chilling surfaces disposed one atop another, wherein the cooling medium passes over each of the chilling surfaces one after another. As above, the cooling medium may enter via the top of the ice tray and cascade down via gravity, or the cooling medium may be introduced from the bottom of the ice tray and pumped upwards over the various chilling surfaces.
[0032] Generally, the invention includes is a system for rapidly cooling a liquid in a container within a refrigerator-freezer or freezer, having: a housing having a space for receiving a container; a rotator adapted to rotate the container; a sprayer adapted to spray chilled cooling medium on the container in the housing; a reservoir adapted to store the cooling medium when the system is not being used and to maintain the cooling medium as a given temperature; and a recirculator adapted to recirculate the cooling medium throughout the system.
[0033] The inventive method preferably includes a number of features to accommodate a variety of different containers. For example, the rotation of the container may be selectively disabled to accommodate containers that may not rotate conveniently (e.g., containers with non-round cross-sections, containers with corners, irregular-shaped containers, etc.).
[0034] Optionally, the device includes a timing means for showering the containers for a pre-determined time sufficient to effect the requisite cooling. The device may be pre-programmed with a set number of different timing sequences and/or rotational speeds depending on the type of container, the type of liquid/beverage, and the desired temperature of the liquid. The device may include a means for continuing the sequence beyond the predetermined period of time if the user wishes to provide extra cooling or warming for the liquid. Temperature sensors may be provided to monitor the reservoir, the liquid in the container, or both. The container sensors may be contact sensors, infrared sensors, or the like.
[0035] The invention may preferably have a drain located at the bottom of the reservoir to enable the system to be drained during cleaning. It may also include an optional inlet line to allow the provision of cooling medium during the initial charge-up, replenishment, and routine cleaning. The invention may also include a timing mechanism that recirculates the cooling medium through the system at certain intervals independent of the consumer and set at predetermined times, based on temperature sensor readings, or based on the time between uses of the system. The invention may also include a sanitizing means such as an ultraviolet light, a chemical in the cooling medium, or another mechanism to sanitize the cooling medium.
BRIEF DESCRIPTION OF THE DRAWINGS
[0036] FIGS. 1A and 1B depict a standard beverage container in the upright and horizontal positions, showing the liquid contents level therein in dotted lines.
[0037] FIGS. 2A-B are rear and side cutaway schematics showing the interior of a previous tabletop embodiment of the invention.
[0038] FIG. 2C is a top view showing the interior of an alternate embodiment of a tabletop version of the invention.
[0039] FIG. 3 is a perspective schematic of the previous tabletop embodiment of FIGS. 2A-B .
[0040] FIG. 4 is a schematic of an embodiment of a control panel for the invention.
[0041] FIGS. 5A-B are schematics of one preferred embodiment of the invention as part of a refrigerator-freezer unit.
[0042] FIGS. 6A-B are perspective schematics of the inside of a door of a refrigerator-freezer in accordance with the invention.
[0043] FIG. 7 is a schematic flow diagram of the embodiment of FIG. 6 .
[0044] FIG. 8 is a side sectional view of a second embodiment of a freezer unit in accordance with the invention.
[0045] FIG. 9 is a front elevational schematic of an embodiment of a refrigerator-freezer unit in accordance with the invention.
[0046] FIGS. 10A-B are side view schematics and FIG. 10C is a top view schematic of ice trays in accordance with the invention.
[0047] FIG. 11 is a front view schematic of another embodiment of a refrigerator-freezer unit in accordance with the invention.
[0048] FIG. 12 is a front view schematic of yet another embodiment of a refrigerator-freezer unit in accordance with the invention.
[0049] FIG. 13 is a side view schematic of a reservoir in accordance with the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0050] Detailed description of the invention will now be provided with reference to FIGS. 1-13 . It should be understood that these drawings and this detailed description are exemplary in nature only, and do not serve to limit the scope of the invention, which is defined by the claims appearing hereinbelow.
[0051] FIGS. 1A and 1B depict a typical 12 ounce beverage container 10 positioned vertically and horizontally respectively. The beverage 11 , contained therein is shown with an air space 12 A in FIG. 1A and a full can length air space 12 B in FIG. 1A . Rotation of the container along its longitudinal axis L, when the container is positioned vertically, results in a rotation of an essentially rigid body with little mixing and extensive cooling times being required. By contrast, the horizontally disposed container 10 in FIG. 1B , when rotated about its longitudinal axis L, results in a high degree of agitation with a high degree of mixing and exchange heat transfer rates.
[0052] FIGS. 2A-B depict a previous stand-alone or tabletop embodiment of the invention as described, e.g., in U.S. Pat. No. 6,662,574 to Loibl et al, the instant inventors. Cooling unit 20 has a housing 22 which has an interior volume or reservoir 32 into which an ice water solution is disposed. The housing is preferably made of plastic, however any material can be used. Housing 22 is preferably double-walled, i.e., has a layer of insulation such as air disposed between two layers of housing material. The air layer serves two insulative functions. First, by insulating the exterior from the ice-cold ice water reservoir, a layer of condensation (“sweat”) will not form on the exterior of housing 22 , an otherwise undesirable occurrence. Second, by insulating the interior from the outside ambient air (which is presumably at room temperature or approximately 25EC), the ice water reservoir 32 remains colder longer because it is absorbing less heat from the environment. Air is an excellent insulator, however other insulation materials may be employed instead of or in addition to air. The two layers also increase the strength of the housing and provide better stability for the system.
[0053] Leaving a gap between the two layers of housing material also enables active control of the temperature of the reservoir in that cooling elements may be disposed between the layers in the bottom and/or sidewalls of housing 22 . For example, such cooling elements may include standard refrigeration coils.
[0054] A container such as soda can 10 is intended to be placed within housing 22 ; depending on the relative height of the support structure upon which the container rests, the container may not be in direct contact with the ice water solution disposed in reservoir 32 , or it may be partially submerged in reservoir 32 . As shown in FIG. 2 , a drive roller 34 is provided on which the container is to be placed. The drive roller 34 preferably includes several spaced apart contact rings 36 upon which the container is intended to be supported. As mentioned above, contact rings 36 provide for better frictional contact between roller 34 and container 10 than a simple smooth roller would provide, because the same weight of the container is contacting a much smaller surface area (i.e., the ring-container interface is significantly smaller than a smooth roller-container interface). The contact rings also allow water (or other cooling medium) that is sprayed onto the container for cooling (see below) to wrap fully around the container and thus contact a greater surface area of the container, thereby maximizing heat transfer. Further, the gaps between adjacent contact rings provide channels into which water may fall off of the container back into reservoir 32 ; this channeling effect helps to prevent hydroplaning of the container on the roller, which would otherwise be caused by a thin layer of water getting trapped between the container and a smooth roller. Of course, a roller of uniform profile may also be employed without departing from the invention. It would be desirable to create good frictional contact between the roller and the container in any event.
[0055] Since roller 34 is circular in section and the majority of beverage containers are also circular in section, single roller 34 by itself provides insufficient support for a typical container, particularly since roller 34 will be rotating and causing can 10 to rotate. Thus, a plurality of ribs 38 (see FIG. 3 ) may be formed in one or both of the side walls to provide lateral support for a container to be placed within cooling unit 20 . That is, when a container is placed therein, it is supported on the bottom by roller 34 and on the side by ribs 38 . Ribs 38 are preferably spaced apart to enable a person to get his/her fingers around the container more easily when removing the container after chilling, and strengthen the wall upon which they are provided.
[0056] The ribs also facilitate the addition of ice into reservoir 32 by providing additional clearance between roller 34 and wall 30 . Were the ribs not provided, wall 30 would need to be moved to where the innermost portions of ribs 38 are, i.e., inwardly closer to the roller, thereby reducing the sectional area through which ice may be added to the reservoir. As with the contact rings 36 , ribs 38 also allow water to flow smoothly entirely around container 10 ; if a smooth wall were provided, the water sprayed on top of the container would flow to the wall/container interface and stop. The ribs allow the water to flow smoothly around the bottom of the container and then neatly collect back in the reservoir. Ribs 38 are preferred but not required; a flat or curved wall or additional roller(s) could be used to provide support for the container as well. As shown in FIG. 2C , convex wall 37 A can be used if the container is rotated in a manner that it is pulling away from the wall. And conversely, concave wall 37 B can be used if the container is rotated in a manner that it is pushing into the wall. Both the concave and convex wall will position the container directly at the center of mass. Alternatively, as shown in FIG. 2C , both convex wall 37 A and concave wall 37 B may be used together for positioning the container. Further, additional support structure may be provided to secure the container and prevent it from falling into the reservoir; for example, a clamp or netting may be provided which keeps the container in contact with roller 34 may be provided in the interior volume of the housing, either attached to a side wall or from the underside of lid 50 , for example.
[0057] As shown in FIGS. 2A-B , a pump 40 is preferably provided, powered by a power supply (not shown), to send water from the ice water reservoir 32 up through tubing or piping 41 to spray jet or nozzle 44 . The floor of housing 22 is preferably angled to cause water in reservoir 32 to collect or pool nearest the pump inlet. In this way, the amount of water required to run the cooling cycle is minimized, thereby allowing a maximum amount of ice to be employed to maximize the amount of heat the ice-water solution can absorb. A grill 43 is provided in front of the intake 42 of pump 40 to minimize air bubbles and large chunks of ice being pulled into the pump.
[0058] Spray jet 44 is designed to shower the circumferential surface of a container placed in the cooling unit with ice-cold water so as to cool the contents of the container. Optionally, an additional spray jet may be provided to coat the bottom surface of a container with a separate jet spray. It is preferred to provide a single spray jet for each surface of the container so that the film of water sprayed onto a given surface of the container is smooth and clings to the container; the provision of multiple spray jets for a given surface (i.e., a number of spray jets positioned above the circumferential surface of the container) is not preferred, because the respective jets of water interfere with each other and prevent a smooth film of water from forming over the entire container. A container must therefore be placed within the cooling unit so that the sprayed water from spray jet 44 will substantially contact the container. In the preferred embodiment shown, since spray jet 44 is only provided in the rear of the cooling unit 20 , the proper placement of the container is extremely important. Accordingly, ribs 38 are not preferably provided as being identical. Rather, the distance from the drive roller to the outer edge of the ribs 38 preferably varies from front to back; that is, front-most rib 38 A is the closest to the roller 34 , rib 38 B is further than rib 38 A, rib 38 C is further than rib 38 B, and rib 38 D is further than rib 38 C. As a result, the profile or outer extent of the ribs is not parallel to roller 34 but rather skewed at an angle from parallel to the roller. The angling of the profile of ribs 38 causes the container placed in the cooling unit to be angled with respect to roller 34 . As such, the roller 34 causes a corkscrew-like rotation in the container with respect to the roller, and container will travel in the longitudinal direction. If the container is made to rotate as shown by arrow A in FIG. 2 , the corkscrew motion will cause the container to travel in the direction of arrow B, towards the rear 26 of cooling unit 20 and thus closer to spray jet 44 .
[0059] The operation of this embodiment of the invention is as follows. Ice is added to reservoir 32 of cooling unit 20 , and then water added to reservoir 32 . Next, container 10 is placed in cooling unit 20 . Can 10 rests on support rings 36 of roller 34 and against ribs 38 projecting from at least one of the side walls of housing 22 . Ribs 38 are angled and cause can 10 to sit on roller 34 askew from the axis of the roller by an angle. Finally, the user selects a button from control panel 60 (or an on-off switch) to activate the device. Roller 34 begins to rotate in this embodiment, which causes can 10 to rotate in the opposite direction as depicted by arrow A. The angle of can 10 with respect to the axis of rotation of roller 34 causes can 10 to migrate in the direction of arrow B towards spray jet 44 . As can 10 rotates, the impinging water jet from spray jet 44 hits the can and is directed by the rotation of the can to coat the can with a thin film heat transfer layer of constantly replenished water at approximately 0° C. At the same time, agitated fluid within the cans presents an extended surface area to the heat transfer effects of the cooling water. The water thereafter falls off of can 10 and drains into the ice water reservoir 32 so that it may be re-cooled to 0° C. and be re-sprayed onto the container. No special suction cups, chambers, or other holding devices are required to keep the container in place for the requisite rotations. The clear advantage of the simple roller and ribs configuration is that the device may accommodate containers of significantly different geometries and sizes.
[0060] One roller may be used to chill two containers on opposite sides (assuming that the dimensions of the containers and the housing allow), and the length of the roller can be increased to accommodate multiple containers at the same time.
[0061] As shown in FIGS. 2A and 2B , roller 34 is rotated by motor 44 in a direct drive configuration. It is also possible to use gearing between the motor and the roller, however the unit operates more quietly and fails less often using a direct drive configuration.
[0062] The longer a container is rotated and sprayed, the cooler the contents become. Accordingly, control panel settings such as “chilled”, “cold”, and “ice-cold” may be provided on a control panel as described below to provide the user with an idea of how cold he/she can make the fluid inside the container. As a simpler alternative, a basic on-off switch may be provided instead of a timing switch.
[0063] One preferred control panel is shown as user interface 60 in FIG. 4 . User interface 60 includes several container selector buttons 62 and an on-off button 64 . The user determines which container he/she is going to be chilling and depresses the appropriate button 62 . The user then presses the start button 64 to begin the chilling cycle. LEDs 63 indicate which chilling cycle has been selected and whether the device is on or off. A computer chip (not shown) or a mechanical timing mechanism (also not shown) may be connected to the container selector buttons 62 which will provide the proper length of chilling cycle for the desired container. In a more advanced embodiment, the selector buttons 62 may also change the volumetric flow rate of the water coming out of the spray jet and/or the speed of rotation of the roller (and thus the speed of rotation of the container); such parameters may be pre-programmed on a computer chip, a programmable logic controller, or the like.
[0064] In the preferred interface 60 of FIG. 4 , the user is also provided with two additional cooling options. The first is a “spray only” button 66 . This feature disables the rotation aspect of the process; roller 34 will not rotate, but spray jet 44 will coat the container with ice-cold water from the reservoir. The “spray only” option allows for the cooling of non-cylindrical containers that would not necessarily rotate smoothly over roller 34 . Also, certain carbonated beverages (e.g., Guinness Stout and Murphy's Stout) are sold in containers having a diaphragm built into the container. The agitation of such a container via rotation may cause the product to fizz over when opened. A consumer may wish to chill champagne via the “spray only” method; champagne is notoriously explosive when disturbed or agitated (even though champagne does not explode when rotated, only when it is shaken). A cooling cycle having spraying without rotating will take somewhat longer than a spraying and rotating cooling cycle, however the fluid will still be cooled quicker than by conventional means.
[0065] A second feature enabled by user interface 60 is the “extra cold” button 67 . By depressing this button in conjunction with any of the container selector buttons 62 , the cooling cycle is extended by a predetermined period of time, depending on which container was selected. This will cool the beverage beyond the initial set point of, for example, 5° C. and bring it down to a lower temperature of, for example, 1 or 2° C.
[0066] Through use of the cooling unit of the invention, eventually all of the ice will melt and the cooling medium in reservoir 32 will begin to heat up. The user interface may preferably include an indicator 65 which informs the user that the ice-water solution is no longer at an optimal temperature. A temperature sensing device, such as a thermocouple, may be disposed in the housing in thermal communication with the reservoir 32 . The temperature sensor may be disposed in reservoir 32 or in or near spray jet 44 , or anywhere else that is convenient in the cooling medium flow path. When the cooling medium temperature rises above a certain point, for example, 3EC, the “Add Ice/Remove Water” indicator 65 is lighted to inform the user that the solution needs replenishing.
[0067] Another feature includes sensing or detecting the temperature of the container itself. This is helpful in determining when a liquid is properly cooled, so that the cooling unit may be deactivated when the set point temperature is reached. A temperature sensor may be provided in or on roller 34 in contact with the container being cooled for a direct contact measurement of the container's temperature, Alternatively, an infrared sensor may be disposed in the interior of housing 22 to visually detect the temperature of the container. An infrared detector might be disposed, for example, on an underside of lid 50 so that it would not be in contact with the cooling medium.
[0068] The rapid cooling unit described above is shown as a stand-alone or tabletop device. As briefly mentioned above, two of the inherent disadvantages of the tabletop version are that it constantly requires its ice supply to be replenished, and it takes up counter top or tabletop space. As such, the inventors have determined that the cooling unit may be incorporated into a refrigerator or freezer as shown in FIGS. 5-13 to thereby take advantage of a source of heat removal (i.e., a source of “cold”) already present in almost every home, the refrigerator-freezer or freezer unit. As an example, refrigerator-freezer 100 may be provided with a conventional ice maker 110 recessed in the front of the unit and may be provided with a beverage chiller 120 in accordance with the present invention. As shown in FIG. 5B , chiller 120 includes at least one roller 134 and a spray jet 144 , both substantially similar to their respective counterparts described in the aforementioned embodiments. Ribs 138 may be provided corresponding in function (positioning, stabilization, etc.) to ribs 38 described above. However, ribs 138 may be removable from the housing of chiller 120 to fit even larger containers such as champagne or 1-2 liter containers. Ribs 138 may be connected to or integral with a removable wall section 131 that can be snapped into place or removed as the consumer desires. Similarly, removable wall section 131 may not be provided with ribs 138 but instead with a convex or concave wall of the type shown in FIG. 2C . Drain or outlet 132 is provided to allow cooling medium runoff to be collected in other components to be described below.
[0069] As illustrated in various embodiments in FIGS. 6-13 , the chief components of the inventive system refrigerator-freezer or freezer unit rapid chilling system are the chiller 120 and the cooling medium chilling means. The chilling means preferably includes one or both of reservoir 160 and ice tray 180 in one form or another. Chiller 120 has essentially been described above, in that a container is placed on roller 134 and rotated about an axis while being sprayed by spray jet 144 with a cooling medium such as water. Reservoir 160 is a collection tank for storing cooling medium and maintaining the cooling medium at a usable temperature. Reservoir 160 is preferably at least partially in thermal communication with the freezer compartment so as to keep the cooling medium retained therein cold without freezing it completely solid (although some ice formation is acceptable and, in fact, desirable). Reservoir 160 is preferably provided with port 163 , for allowing the system to be filled with cooling medium and/or cleaning solution, and drain 165 for allowing the cooling medium (or cleaning solution) to be removed from the system for cleaning, maintenance, and the like. A sanitizing means 167 is provided in the system, preferably within reservoir 160 . Sanitizing means 167 may be an ultraviolet light that kills bacteria that may form in the cooling medium. Alternatively or in addition, sanitizing means 167 may be a device that generates ozone or releases another chemical for the purposes of sanitizing the system. Such a chemical may be released periodically or continuously, depending on design requirements.
[0070] Typically, a pump 170 is provided in or near reservoir 160 so as to enable the circulation of the cooling medium between/among the various components of the system. The pump causes the cooling medium to flow so that when the user wishes to cool a beverage in chiller 120 , cooling medium showers the beverage container. The pump may also be provided with a recirculating timing mechanism that causes the system to run at predetermined intervals so that the cooling medium does not freeze completely solid in any point of the system and to prevent any particulate matter (which might be picked up from a dirty beverage container, for example) from settling in one place and potentially clogging the system.
[0071] The term “ice tray” does not refer to a conventional device for making and storing ice cubes as found in a conventional freezer but to the type of chilling element described hereinbelow and equivalents thereof. The inventive ice tray is an element having one or more chilling surfaces in thermal communication with the freezer compartment (which may be the sole cold compartment of a freezer unit or the colder compartment of a refrigerator-freezer unit). The cooling medium is directed to flow over the chilling surface, upon which the cooling medium is chilled. If the cooling medium is water, ice preferably forms upon the chilling surface(s) of the ice tray. It is here where ice is essentially “stored” for use in the cooling process, instead of having to replenish ice as in the tabletop model. The area of the chilling surface is determined to be great enough so that the system may be used substantially continuously for chilling beverages or other liquids in succession without having to stop to allow the cooling medium to cool off. More specific descriptions of various embodiments of ice trays will be described below.
[0072] The three main components, the chiller, the ice tray, and the reservoir, are all in successive communication with one another so that cooling medium exits one component and enters the next component. The invention may be configured with the ice tray between the outlet of the chiller housing and the inlet of the reservoir, or with the ice tray between the outlet of the reservoir and the inlet of the chiller housing, or in any combination or permutation of the three elements. More than one ice tray may be used in the system and may be disposed substantially anywhere in the system.
[0073] Description of several specific preferred embodiments follow.
[0074] One preferred embodiment is shown in FIGS. 5-7 which incorporates the inventive rapid fluid cooling system into a refrigerator-freezer 100 . It should be noted that, although refrigerator-freezer 100 is shown to be a “side-by-side” model, it is contemplated that the inventive system may be incorporated into a “top and bottom” refrigerator-freezer unit as well.
[0075] In this embodiment, chiller 120 is formed in the door 108 of unit 100 . Chiller door 150 is provided to cover chiller 120 during use (e.g., to prevent splashing of the cooling medium) and when not in use (e.g., to insulate the unit better). Door 150 is shown as hinged to be openable to allow access to place or remove a container from within chiller 120 , however a sliding door or any other type door may be employed as well. FIG. 6A shows a general broad schematic of this particular embodiment, in which ice tray 180 is disposed atop chiller 120 and reservoir 160 is disposed at the bottom. All three elements are disposed in door 108 of the freezer section of unit 100 . Greater detail of this embodiment is shown in FIGS. 6B and 7 . In this embodiment, the outlet of ice tray 180 feeds directly into the inlet or spray nozzle 144 of chiller 120 , and the outlet 132 of chiller 120 feeds into inlet 162 of reservoir 160 via piping 155 .
[0076] There are two ways that ice tray 180 may be operated, both of which are shown in FIGS. 6B and 7 and alternatively shown in FIGS. 10A and B (only one way would be employed in a given unit) as ice tray 180 or 180 ′. In the first configuration shown in FIG. 10B in detail, ice tray 180 has an inlet 182 at its bottom portion and receives pressurized cooling medium from the bottom courtesy of pump 170 in reservoir 160 . This embodiment includes at least one and preferably multiple stages 188 attached at least on one end to side walls 187 and 189 . Stages 188 may be cantilever (as shown in FIG. 10A ) and have a fixed end 190 (attached to a side wall 187 or 189 ) and a free end 192 . Alternatively, stages 188 may each be attached to both side walls 187 and 189 (as shown in FIG. 10B ). In this latter arrangement, it would be necessary to provide holes 194 in stages 188 so that the cooling medium may circulate through successive stages 188 of ice tray 180 . In any event, in this first configuration, inlet 182 is provided on the bottom of ice tray 180 and receives cooling medium from reservoir 160 via piping 172 in the direction of arrow A ( FIG. 7 ). Each stage 188 has chilling surfaces 181 which, when they come into contact with the cooling medium, reduces the temperature of the cooling medium. Stages 188 are in thermal communication with the freezer compartment of unit 100 , either directly or via fins (not shown) or both. As the cooling medium is pumped upwards through successive stages 188 of ice tray 180 , the various chilling surfaces 181 (which may also include side walls 187 and 189 ) chill the cooling medium. When the cooling medium reaches the top stage 188 of ice tray 180 , the cooling medium exits ice tray 180 via outlet 184 , whereupon it is conducted to spray nozzle 144 of chiller 120 via piping 186 . After being used to cool a liquid in a container in chiller 120 , the cooling medium drains out of chiller 120 via outlet 132 , whereupon it is conducted to reservoir 160 via piping 155 in the direction of arrow B ( FIG. 7 ).
[0077] The other version of the ice tray, ice tray 180 ′, is shown in detail in FIG. 10A and also in FIGS. 6B and 7 . Stages 188 are provided as above, and again, the stages may be cantilever or fixed at both ends and provided with holes 194 . In this embodiment, inlet 182 ′ of ice tray 180 ′ is disposed on the top portion of ice tray 180 , and the cooling medium is allowed to cascade down over successive stages 188 via gravity. In this embodiment, should the cantilever design be employed, it is preferred to provide a raised lip 195 at the free end of the stage 188 so that cooling medium may accumulate and pool a bit prior to spilling over lip 195 and down onto the next stage 188 . The longer the cooling medium remains on a chilling surface 181 ′, and the more the cooling medium is spread out evenly and thinly over chilling surfaces 181 ′, the more it is cooled, and the more ice will be formed (assuming water or something similar is the cooling medium). Stages 188 , be they cantilevered or fixed, may be angled downward towards either their respective free ends 192 or their respective holes 194 so as to insure the cooling medium does not back up and does flow onward to the next successive stage. In any event, in this second gravity-driven configuration, inlet 182 ′ is provided on the top of ice tray 180 ′ and receives cooling medium from reservoir 160 via piping 172 in the direction of arrow A ( FIG. 7 ). Each stage 188 has chilling surfaces 181 ′ which, when they come into contact with the cooling medium, reduce the temperature of the cooling medium. As above, stages 188 are in thermal communication with the freezer compartment of unit 100 , either directly or via fins (not shown) or both. As the cooling medium cascades downward over successive stages 188 of ice tray 180 ′, the various chilling surfaces 181 ′ chill the cooling medium. When the cooling medium reaches the bottom stage 188 of ice tray 180 ′, the cooling medium exits ice tray 180 via outlet 184 ′, whereupon it enters spray nozzle 144 of chiller 120 . After being used to cool a liquid in a container in chiller 120 , the cooling medium drains out of chiller 120 via outlet 132 , whereupon it is conducted to reservoir 160 via piping 155 in the direction of arrow B ( FIG. 7 ).
[0078] In both of the embodiments of FIGS. 10A and 10B , i.e., the pressurized ice trays and the gravity-driven ice trays, small posts or protrusions 183 are preferably provided extending from chilling surfaces 181 , 181 ′ for the purpose of creating turbulence in the flow of the cooling medium. Posts 183 may be substantially cylindrical or of other geometric configurations. The distribution of posts 183 shown in FIGS. 10A-B is not representative of and not meant to be limiting as a specific pattern of post distribution contemplated as part of the invention.
[0079] FIG. 8 is a side sectional schematic of a chilling system similar to that shown in FIGS. 6 and 7 , i.e., freezer door mounted, except that here, chiller 120 is atop ice tray 188 , which is in turn atop reservoir 160 . This system is well-suited for small freezer units but may be employed in larger units and refrigerator-freezer units as well. The left side of the drawing is the freezer compartment, which is kept at around −15° C., and the right side of the drawing is the outside of the unit, which is ambient air of approximately 22° C. Chiller 120 has a front face exposed to ambient air, i.e., the opening into which a user places the container for rapid chilling. Insulation 202 is provided on the freezer side of the chiller to substantially thermally isolate chiller 120 from the freezer compartment so that heat does not leak into the freezer compartment via chiller 120 . Therebelow is provided ice tray 180 . Because stages 188 are designed to be in thermal communication with the freezer compartment, no insulation is provided between the freezer compartment and ice tray 180 . This allows stages 188 and their respective chilling surfaces to be maintained at −15° C. or thereabouts so that ice may form on the chilling surfaces and so that cooling medium passing over the chilling surfaces is chilled. However, insulation 208 is provided between ice tray 180 and the ambient air to substantially thermally isolate ice tray 180 from the ambient air so that the ice tray remains chilled and heat does not leak into the freezer compartment. Finally, reservoir 160 is provided with insulation 206 A between it and the freezer compartment and insulation 206 B between it and the ambient air. Insulation sections 206 A and B are not so thick that they completely thermally isolate reservoir 160 from either the freezer compartment or the ambient air. Rather, the insulative properties of insulation sections 206 A and B are selected so that the reservoir—and the cooling medium therein—is maintained substantially at a desired temperature above freezing. Of course, if a cooling medium with a very low melting point, such as propylene glycol, is used, the temperature of the cooling medium may be allowed to approach that of the freezer compartment and less insulation may be required.
[0080] In all of the above embodiments, the components of the inventive chilling system are disposed in the freezer compartment (they may be disposed inside the actual compartment or within the door of a compartment or attached to an inside surface of the door; the door is considered part of the compartment). However, the invention will work equally well with one or more of the components disposed in the warmer refrigerator compartment, albeit with at least part of the system in thermal communication with the colder freezer compartment. FIG. 9 depicts a refrigerator-freezer unit 200 having chiller 220 disposed within the freezer compartment, an ice tray 280 disposed above chiller 220 also in the freezer compartment, and a reservoir 260 disposed in the refrigerator compartment. As above, the cooling medium is pumped out of reservoir outlet 264 via pump 270 into inlet 282 of ice tray 280 . From ice tray 280 , the cooling medium passes into the chiller 220 . Used cooling medium leaves chiller 220 via outlet 232 and is conducted back to inlet 262 of reservoir 260 . Reservoir 260 is provided with at least one fin 266 which, at one end, projects into the freezer compartment. In the embodiment shown, fin 266 is an L-shaped flat piece of metal or similar material having good thermal conductivity. Any other practical or effective-shaped fin is contemplated.
[0081] Ice tray 280 in this embodiment may be slightly different from those described above. As shown in the top view schematic of FIG. 10C , ice tray 280 is a single-stage broad element. Cooling medium enters via inlet 282 and passes over a partial barrier or lip 286 . Lip 286 is provided to prevent back flow of the cooling medium and to encourage ice growth. Internal baffles 288 are walls that are the full height or thickness of ice tray 280 , and they conduct the flow of the cooling medium to insure the cooling medium spreads over the entire chilling surface 281 of ice tray 280 . Posts 283 protrude from chilling surface 281 serve to create or enhance turbulence in the flow of the cooling medium and to increase the rate of heat transfer across the chilling surface. Outlet 284 is at least partially (and preferably, completely) surrounded by a partial barrier or lip 289 . The provision of lips 286 and 289 insures that the cooling medium lingers over the chilling surface for as long as possible and enable ice to form in the ice tray. This type of ice tray 280 may also be provided in stages.
[0082] As mentioned above, other combinations of the main components are possible. For example, in FIG. 11 , chiller 220 , ice tray 280 , and reservoir are all disposed in the refrigerator compartment. Here, both ice tray 280 and reservoir 260 are flat and can serve as shelves for the user to place items upon, i.e., food. In this embodiment, ice tray 280 is provided with a fin 266 A, having a large surface area, in the freezer compartment, and a rod 266 B attached thereto and projecting into the ice tray. Reservoir 260 may also be provided with a fin (not shown).
[0083] Another combination is shown in FIG. 12 . Here, ice tray 280 is provided above chiller 220 , and a supplemental ice tray 280 A is provided below chiller 220 . Supplemental ice tray 280 A feeds into reservoir 260 . The primary ice tray 280 may be disposed either above or below chiller 220 , and the supplemental ice tray is optionally provided also either above or below chiller 220 , or anywhere in the cooling medium circuit.
[0084] As mentioned above, the inventive system may be used without ice trays altogether. FIG. 13 depicts a portion of such a system. Reservoir 260 is connected thermally to the freezer compartment by a fin system that passes through the compartment wall. Specifically, the fin system has a number of fins 266 A disposed in the freezer compartment and a rod 266 B projecting into reservoir 260 . Ice 261 forms around rod 266 B. The transient growth rate of ice is constrained by the convective heat transfer between the air and the system (both refrigerator and freezer). On the other hand, there is a great degree of control of the total quantity of ice that can form at steady state by suitable design choices. To maximize the amount of ice formed, an effective fin system (perhaps coupled with an active fan to enhance heat transfer rate) on the freezer side is needed, while reservoir 260 should be insulated somewhat on the refrigerator side.
[0085] Desired use patterns of the system may be defined in terms of total beverages per day and/or the requirements for continuous chilling. The total amount of ice formed at steady-state provides a means for storing an energy sink during active chilling. Approximately 100 grams (0.1 liters) of ice is needed to chill a standard 12 oz. beverage. If, for example, it is required that 10 beverages be chilled in succession before the ice is consumed, then the system must form approximately 1 kg (1 liter) of ice at steady state. The active load of chilling is approximately 500 watts for canned beverages. For continuous chilling, ice must be formed at the same energy equivalent rate, and heat must be transferred from the freezer fins to the freezer air at the same rate, or an ice surface area must be provided that can absorb 500 watts of heat and provide enough mass of ice to be able to handle the desired quantity of beverages.
[0086] The invention is not limited to the above description. For example, the invention describes the container as being placed horizontally within the housing of the device. However, the container may be placeable at an angle to the horizontal and still be within the scope of the invention. One way this could be accomplished is by the angling of the roller away from the horizontal. The container may be at an angle of as much as 45° and still be within the scope of the invention. The angling of the container allows for certain open containers to be chilled with the inventive process, e.g., open bottles of wine. It would be recommended that the bottle be recorked prior to chilling, however recorking may not be required. The pump and motor are electrically interconnected with a computer controller which is preprogrammed with time parameters for cooling of the cans based on the desired temperature, can material and size of the can, with information entered via a keyboard. In other embodiments, such parameters can be readily written into EPROM for dedicated microprocessor control. At the appropriate cooling time, the pumps and motor stop and the beverage cans can then be removed from the device.
[0087] The cooling medium to be used in the invention is not limited to water. Other fluids such as propylene glycol, alcohol, and the like, as well as chilled gases, may be employed. In another variation, water may be used with a solute that could both depress the freezing point of the water and sanitize or sterilize the water, e.g., an ethanol/water mixture, water with calcium chloride, etc. The cooling medium may work in conjunction with sanitizing means 167 described above. Similarly, the materials out of which the components of the system may be made can be virtually any material exhibiting adequate thermal properties that will be non-reactive to the cooling medium selected. It is preferred that the ice trays of varying designs described above and their equivalents have at least their chilling surfaces made from metal having good to excellent thermal conductivity. Indeed, the entire ice tray may be made from such metal.
[0088] Having described the invention with regard to specific embodiments, it is to be understood that the above description is not meant as a limitation excluding such further variations or modifications as may be apparent or may suggest themselves to those skilled in the art. The invention is defined by the claims appearing hereinbelow.
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A system for rapidly cooling a liquid in a container within a refrigerator-freezer or freezer is provided. The housing has a space for receiving a container, and a rotator rotates the container about an axis. While the container is rotating, a sprayer sprays chilled cooling medium on the container in the housing. A reservoir stores the cooling medium when the system is not being used and maintains the cooling medium at a given temperature. At least one chilling surface is preferably provided over which the cooling medium flows and where ice may be stored. A recirculator such as a pump recirculates the cooling medium throughout the system.
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DESCRIPTION
1. Phagocyte-a cell that engulfs bacteria and other foreign particles by phagocytosis.
2. Macrophage-a cell derived from the reticuloendothelial system that functions in phagocytosis. Macrophages are phagocytes.
3. Activate-transforming a cell from a resting state to one where it actively performs its biological function. For example, a macrophage or phagocyte is activated when it encounters a foreign object. Upon encountering the foreign object, the macrophage releases a respiratory burst of oxidizing chemicals to kill or otherwise destroy the object.
4. Elicit-to evoke a response from a cell. For example, foreign objects might be provided to macrophages to elicit the respiratory burst activity.
5. Priming-converting a cell from one state to another, whereby its primed state is more active to a biological substance than if the cell had not been primed. In this patent, the difference between priming a macrophage, as opposed to activating a macrophage or eliciting a response, is very important.
6. Cytokine-a group of substances formed by an animal in response to infection. Cytokines are similar to hormones in their function, whereby they are produced in one cell and stimulate a response in another cell. Cytokines includes such substances as interferon, interleukin, and tumor necrosis factor.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention is generally related to priming macrophages for enhanced killing potential. More particularly, the invention includes administering a priming factor to a patient so that the macrophages in the patient will be primed for enhanced killing activity a certain number of days after the priming factor was administered.
2. Description of the Prior Art
It is now well understood that phagocytes, such as alveolar macrophages and the like, play an important role in controlling microbial infections. Baboir, New Eng. J. Med., 298:659-68 (1978), has explained that upon encountering a foreign material, such as an invading bacterial cell, phagocytes produce a respiratory burst wherein highly oxidative species, such as superoxide anion (O 2 - ), singlet oxygen (O 2 ), and hydrogen peroxide (H 2 O 2 ), are produced. The purpose of the respiratory burst is to provide a battery of oxidizing agents that can be used by the phagocyte for the destruction of invading micro-organisms and other foreign material. Many agents, both particulate and soluble, are able to activate the respiratory burst. Particulate activating agents include opsonized bacteria, zymosan (a preparation of yeast cell walls), and latex spheres. Among the soluble activating agents are phorbol myristate acetate, a complex plant product; a variety of ionophores; the complement C5a; and fluoride ion. Activation may not require phagocytosis; rather, simply contact of the foreign stimulant with the phagocyte surface may be enough to activate the phagocyte to produce the respiratory burst. The oxygen-dependent cytotoxic mechanisms of phagocytes are discussed at length in Klebanoff, Adv. Host Def. Mech., (Vol. 1, eds. J. Gallin and A. Fauci, Raven Press, New York 1982 pp.111-163).
Baboir also explains that the respiratory burst activity can be detected by monitoring the chemiluminescence phenomena wherein light emission accompanies activation of the phagocyte. The light emission stems from the oxidative species produced by the phagocyte. For example, singlet oxygen is an electronically excited state of oxygen that can revert spontaneously to atmospheric oxygen, and this reversion is accompanied by a pulse of light. However, it is now generally believed that superoxide anion is responsible for the chemiluminescent response.
Many researcher groups have used chemiluminescence to study macrophage activity. For example, Donaldson et al., Br. J. exp. Path., 65:81-90 (1984), used chemiluminescence measurements to show that macrophages treated with chrysotile asbestos and Cornyebacterium parvum elicited greater levels of reactive oxygen species than saline treated macrophages. In addition, Donaldson showed that peritoneal exudate cells harvested from CF I mice five days after injection with chrysotile asbestos or C. parvum had a approximately a two to three fold increase in measured chemiluminescence. Donaldson et al. suggest that the asbestos-activated macrophages are primed to produce increased amounts of reactive oxygen species which could be triggered by a number of inhalable particles (e.g., bacteria, yeast, pollen, and asbestos itself), and that an excess of these reactive oxygen species in the alveolar spaces leads to epithelial damage and ultimately to fibrosis. Other examples where chemiluminescent response measurements were used include: Chida et al., Infect. Immun., 55:1476-1483 (1987), reports on a study where infant and mature rabbits were vaccinated with the heat killed Bacillus Calmette Guerin (BCG) strain of Myobacterium bovis and shows that the alveolar macrophages (AM) of infant rabbits were poor responders to phorbol myristate acetate (PMA)-induced chemiluminescent responses compared to AM from older rabbits which were vaccinated with BCG, thus illustrating a deficiency in the AM of neonatal and infant animals that may account for their increased susceptibility to pulmonary infections; Hayakawa et al., J. Leuk. Biol., 45:231- 238 (1989), reports on a study where a chemiluminescent assay was used to show that AM from BCG vaccinated rabbits (3 weeks after i.v. injection), when cultured in vitro with various serum preparations, could result in significant changes in the chemiluminescent (CL) response; Myrvik et al., J. Invest. Surg., 2:381-389 (1989), reports on a study where extracellular slime from Staphyloccocus epidermis was found to affect the CL response on PMA-induced rabbit AM; Umehara et al., Cell. Immun., 119:67-72 (1989), reports on a study where CL responses were used to show L-Fucose blocks migration inhibition factor (MIF)/macrophage activation factor (MAF) priming of rabbit AM (PMA-induced oxidative response used); Giridhar et al., J. Leuk. Biol., 49:442-448 (1991), reports on a study where CL responses were used to show priming of rabbit AM by herpes simplex virus type 2 infection.
There has been much effort made in finding materials which can provide protection from infection. U.S. Pat. Nos. 4,707,471 and 4,795,745 to Larm et al. disclose that pretreatment with water soluble aminated β-1,3-D-glucans can stimulate the activity of macrophages such that animals are protected from virulent pneumococci. U.S. Pat. No. 5,045,320 to Mescher discloses that immunization with a solid support having a variety of different ligands attached can elicit and augment T cell mediated responses U.S. Pat. No. 4,900,722 to Williams et al. discloses a class of phosphorylated glucans useful in the treatment of infections. U.S. Pat. No. 5,078,996 to Conlon et al. discloses the use of granulocyte stimulating factor to activate macrophage tumoricidal activity U.S. Pat. No. 3,119,741 discloses an acylated bacterial lipopolysaccharide useful as a non-specific immunological agent.
There is a need for a short-term, non-specific therapeutic which provides protection against a wide variety of bacterial and viral infections. Such a therapeutic could ideally be used in anticipation of events which lead to infections such as surgery, biological warfare, natural disasters and the like. Up-regulation of the macrophage oxidative killing potential could be beneficial to such an end; however, the time duration for such priming would advantageously be limited so as to avoid cellular and matrix protein damage, fibrosis, and other injuries which would occur from the chronic production of reactive oxygen species.
SUMMARY OF THE INVENTION
It is therefore an object of this invention to provide an immunomodulation technique for non-specific cellular immune stimulation.
It is another object of this invention to provide a method for up-regulating macrophages for a short duration by using phagocytosable particulates to prime the macrophages for a short period of time.
It is yet another object of this invention to provide compositions suitable for use in priming macrophages for enhanced killing potential.
According to the invention, macrophages can be primed for a markedly enhanced oxidative response by injecting a patient with phagocytosable particles a few days before the enhanced activity is required. Experiments suggest that the primed macrophages could have greater than 100 times the activity potential than normal, non-primed macrophages. However, the priming is for a short duration and wears off to normal after a week so that the treatment process does not pose long term hazards for enhanced in vivo reactive oxygen production.
In the experiments, adult rabbits were injected intravenously (i.v.) with phagocytosable (1-5 μm) particulate preparations such as zymosan, latex particles or heat-killed BCG. The preparations primed AM rapidly in 1-4 days for greatly enhanced phorbol myristate acetate (PMA) or opsonized zymosan (Op-zym) elicited chemiluminescent (CL) responses. AM obtained from particle injected rabbits showed more than 100-fold higher levels of CL responses than AM from normal rabbits Specifically, AM from resident rabbits normally generate about 3,000 cpm when challenged with PMA, whereas AM from rabbits injected i.v. with 20 mg of zymosan three days prior to harvesting AM, generated up to 900,000 cpm when challenged with PMA. In contrast, the particles failed to prime normal AM in vitro for enhanced CL responses. Furthermore, AM could not be primed in vivo with non-phagocytosable (-25 μm diameter) particles. The priming effect was of short duration and declined 5 to 7 days after injection of the particle preparations It was also observed that AM from normal rabbits could be primed in vitro for enhanced CL responses by incubating AM for 3 to 18 h with the lung lavage fluids obtained from particle-primed rabbits which suggests the presence of a macrophage priming factor(s) in the lung lavage fluid.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing and other objects, aspects and advantages will be better understood from the following detailed description of a preferred embodiment of the invention with reference to the drawings, in which:
FIG. 1 is a graph showing in vitro priming of normal rabbit AM with BAL extracted from rabbits injected with zymosan 1, 2, or 3 days prior to harvesting AM for enhanced PMA-elicited CL responses; and
FIG. 2 is a graph showing in vitro priming of normal rabbit AM with various concentrations of BAL extracted from zymosan injected rabbits for enhanced latex elicited CL responses.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION
A number of experiments have been performed which demonstrate that phagocytosable particles are effective for up-regulating macrophages for short duration.
1. Materials and Methods
Reagents
Tissue culture reagents were purchased from Curtin Matheson Scientific Company, Inc. (Columbia, Md.). Polystyrene and PMMA latex particles were purchased from Polysciences, Inc. (Warrington, Pa.). Other chemicals were purchased from Sigma Chemical Company (St. Louis, Mo.) unless otherwise specified.
Animals
New Zealand white SPF rabbits of either sex, 4-5 months old, were purchased from Hazleton Research Products, Inc. (Denver, Pa.). The animals were housed for 3-4 days in our animal facility to allow the animals to adjust to their new environment before being used.
Collection of Macrophages
Rabbits were sacrificed by pentobarbital given i.v. (75-85 mg/kg) or rabbits were anesthetized with Ketamine/rompon (40 mg/kg and 5-10 mg/kg i.m.) and then exsanguinated or given air embolism while under anesthesia. AM were harvested by lung lavage technique described in Myrik et al., J. Immunol. 86:128-132 (1961), which is herein incorporated by reference, using 200 ml of cold saline. The harvested cells were washed 3× by centrifugation (200× g, 10 min) in RPMI 1640 medium (pH 7.2) containing penicillin (100 U/ml), streptomycin. (100 μg/ml), and L-glutamine (2 mM), but without phenol red and serum. The cells were resuspended in the same medium to obtain a cell density of 3×10 7 cells/ml.
Cell Viability
The viability of the AM was determined by trypan blue (0.25%) exclusion staining.
Protocol for In Vivo Priming of Rabbit AM
To prime AM in vivo, adult rabbits were injected i.v. with 10 mg of heat-killed BCG strain of Mycobacterium bovis suspended in 4 ml of saline or with 20 mg of zymosan in 2 ml of saline. The AM were harvested 1 to 7 days after injection.
Chemiluminescence Assay
The CL response was assayed by a previously described procedure of Girdhar et al., J. Leuk. Biol. 49:442-448 (1991), which is herein incorporated by reference. The assay was done in diffused light using dark-adapted 3.5 ml polypropylene scintillation vials. A typical assay mixture consisted of 3 ml Hanks' Balanced Salt Solution (HBSS) (pH 7.2) at 37° C., 0.1 ml cell suspension (3×10 6 cells), and 30 μl, 0.5 μg/ml), latex (7.5 μl, 250 μg/ml), Polybead Polystyrene Microspheres, 2.5% solid latex of 1.03 μm diameter, or opsonized zymosan (Op-zym), (30 μl; 100 μg/ml) were added to elicit the CL response. The counts per minute (cpm) were recorded by scintillation spectrometry using a Beckman LS 100 C scintillation counter.
Collection of Bronchoalveolar Lavage Fluids (BAL)
BAL were collected from control as well as particle-primed rabbits. Lungs removed from rabbits were lavaged using 100 ml of cold saline, and the fluids were centrifuged at 300× g for 10 min to remove the cells and cell debris. The supernatant fluids were centrifuged at 60,000× g for 2 h at 4° C., and the supernatant fluids were filtered (0.45 μm pore size) and used as crude BAL containing the putative macrophage priming factor (MPF).
In Vitro Priming of Normal Rabbit AM with BAL
Freshly-harvested AM from normal rabbits were incubated with various concentrations (10 to 100%) of BAL from primed animals for 3 to 18 h in RPMI 1640 medium at a cell density of 1×10 6 /ml in Teflon flasks. After incubation, the cells were washed 2× with RPMI 1640 medium and assayed for a CL response with PMA or OP-zym as the eliciting agents. AM incubated with or without BAL from normal animals served as controls.
2. Experiments
In Vivo Priming of AM in Adult Rabbits Following Zymosan Administration for Enhanced Oxidative Responses
Adult rabbits were injected i.v. with 20 mg of zymosan particles in 2 ml of saline. On the days following injection, the animals were sacrificed, AM was harvested, and either PMA or Op-zym was used to elicit chemiluminescence from the harvested AM. Table 1 presents the measured cpm*10 -4 ±SEM for the two eliciting agents on the test days.
TABLE 1______________________________________Days Oxidative Responses (CPM* 10.sup.-4)After Eliciting AgentsPriming PMA Op-zym______________________________________0 (control; no injection) 0.3 ± 0.5 7 ± 2.51 7.0 ± 1.1 17 ± 3.82 25 ± 5.2 45 ± 8.33 92 ± 10.1 >1004 7 ± 2.5 12 ± 2.45 5 ± 0.3 21 ± 2.27 4 ± 0.4 25 ± 8.5______________________________________
Table 1 shows a very dramatic short-term priming effect caused by the injected particles. While the CPM values increased immediately after injection, unusually high levels of PMA- or Op-elicited oxidative responses was observed when particles were administered three days prior to harvest. AM harvested three days after zymosan injection generated a PMA-elicited CPM of more than 900,000 and Op-zym-elicited CPM were greater than 1,000,000. In addition, an increase in the resting values from less than 500 CPM for normal AM to about 2,000 CPM for primed AM was also observed (resting values being the CPM when no eliciting agent was provided). The decline in the oxidative response observed from days 4 to 7 demonstrates that the observed particle induced priming of the macrophages was for only a short duration.
Alternate modes of administration, such as intratracheal microdroplet instillation (e.g., aerosols and the like), yielded similar results. Adult rabbits were injected intratracheally (i.t.) with 20 mg of zymosan in 2 ml of saline four days prior to harvesting their AM. Control rabbits received 2 ml of saline. The harvested AM were assayed for CL responses with PMA or Op-zym as eliciting agents. Table 2 presents data showing enhanced oxidative responses for AM obtained from rabbits injected i.t. with zymosan (data represent three separate experiments).
TABLE 2______________________________________ Oxidative responses (CPM* 10.sup.-4)Particle Eliciting Agentsinjected PMA Op-zym______________________________________Saline (control) 0.2 5.1Zymosan (20 mg) 14.6 >100______________________________________
Table 2 shows that AM from rabbits injected i.t. with 20 mg of zymosan 4 days prior to harvesting AM generated Op-zym elicited CL responses of more than 1,000,000 CPM.
Cell Analysis of Lavagates from Zymosan-Injected Animals and Evidence that AM are Involved in the Priming Response
Adult rabbits were injected i.v. with 20 mg of zymosan in 2 ml of saline. Groups of rabbits were sacrificed and the cells (AM) were harvested by lavage 1, 2, 3, or 4 days after zymosan injection. The viability of the cells was determined by the trypan blue exclusion test and differential cell counts were determined by evaluating cytocentrifuge slide preparations stained with Wright-Giemsa solution. Table 3 presents the differential numbers of AM, lymphocytes (Lym) and polymorphonuclear leukocytes (PMN) from normal and zymosan injected adult rabbits (results are ±SEM (n=4)).
TABLE 3______________________________________Days After iv Differentiation of Cell Counts (%)injection AM Lym PMN______________________________________Control 95.5 ± 22.0 5.0 ± 1.1 1.1 ± 0.21 72.2 ± 15.5 1.9 ± 0.7 24.7 ± 13.82 78.5 ± 9.3 5.5 ± 2.6 16.2 ± 8.23 84.8 ± 0.8 9.0 ± 1.0 6.3 ± 2.24 95.4 ± 5.3 2.8 ± 3.1 1.9 ± 2.2______________________________________
Table 3 shows that total neutrophils comprised about 25% of the total recovered on day 1, 16% on day 2, 6% on day 3 and 2% on day 4. In view of the fact that AM from zymosan-injected rabbits exhibited about a 20 to 200-fold increase in Op-zym or PMA elicited CL responses compared to AM from control rabbits (Table 1), and that the in vivo priming effect was highest on day 3 when the AM population was 85% and the RMN population was only about 6% of the cells harvested (Tables 1 and 3), the data establish AM was the predominant cell population involved in the generation of the oxidative burst.
Comparative In Vivo Priming of AM From Adult Rabbits Following i.v. Injection of Zymosan, HK-BCG or Latex Particles
To study the comparative effects of other particles on priming macrophages, adult rabbits were injected i.v. with 20 mg latex in 2 ml saline, 20 mg zymosan in 2 ml of saline, or 10 mg heat killed (HK)-BCG in 4 ml of saline two days prior to harvesting AM. Oxidative responses were then elicited by PMA (0.5 μg/ml), latex (100 μg/ml) or opsonized zymosan (100 μg/ml). Table 4 presents data showing the in vivo priming of adult rabbit AM by zymosan, HK-BCG, and latex for enhanced oxidative responses elicited by PMA, latex, and op-zym.
TABLE 4______________________________________ Oxidative Responses (CPM* 10.sup.-4)Particles Conc. Eliciting Agentsinjected (mg) PMA Latex Op-zym______________________________________Control 0 0.25 ± 0.03 0.5 ± 0.2 7.5 ± 1.5Zymosan 20 6.2 ± 0.3 11.5 ± 2.2 46.0 ± 3.6HK-BCG 10 8.3 ± 0.4 >100Latex 20 3.3 14.9______________________________________
Table 4 shows that HK-BCG and latex particles were also highly effective in priming normal rabbit AM in vivo for markedly enhanced CL responses. Preliminary results with other particles have been similar. The results indicate that the in vivo priming of normal rabbit AM is non-specific with respect to the types of particle preparations injected into the rabbits as well as with respect to the eliciting agents. It is preferable that the particles that are administered be biodegradable within a few days after their priming function is fulfilled. Specifically, particles should remain substantially intact for 1-4 days to achieve the priming function presented in the above tables; however, after the fourth day, when the priming function has been found to diminish (Table 1), the particles would preferably be broken down by bodily functions so that the particles themselves would not present a medical challenge to the patient.
Failure of Non-Phagocytosable (˜25 μm) Latex Particles to Prime AM In Vivo
In the above experiments, the particles employed were phagocytosable (e.g., 1-5 μm in diameter). To determine whether the size of the particle plays an important role in priming the macrophages, adult rabbits were injected i.v. with 20 mg of non-phagocytosable latex particles on the order of 25 μm in diameter. The latex beads were suspended in 2 ml of saline. AM were harvested two days after injection and assayed for PMA or Op-zym elicited CL responses. Table 5 shows that i.v. injection of adult rabbits in vivo with 20 mg of non-phagocytosable latex particles approximately 25 μm in diameter did not result in priming AM.
TABLE 5______________________________________ Oxidative Responses (CPM* 10.sup.-4)Source Eliciting Agentsof AM PMA Op-zym______________________________________Control Rabbit 0.4 ± 0.1 7.0 ± 1.1Latex-injected 0.8 ± 0.09 0.6 ± 0.05Rabbit______________________________________
Table 5 clearly shows that priming which results from prior treatment with non-phagocytosable particles was insignificant. Contrasting Table 5 with the results above, clearly the size of the particle plays an important role in priming macrophages for enhanced killing potential.
Failure of Zymosan to Prime Normal AM In Vitro
To determine whether zymosan particles can prime normal resident AM in vitro, freshly harvested AM from normal rabbits were incubated with 5 mg zymosan/ml of AM suspension in RPMI 1640 medium for 18 hours at 37° C. in 5% CO 2 . AM incubated without zymosan served as controls. After incubation, the cells were washed and assayed for CL responses using PMA as the eliciting agent. Table 6 shows that zymosan particles did not prime normal AM in vitro for enhanced oxidative responses as they did when injected i.v. into rabbits.
TABLE 6______________________________________Treatments Chemiluminescence (CPM* 10.sup.-4)of AM Resting Peak______________________________________AM incubated alone 0.1 ± 0.02 2.5 ± 1.1AM incubated with 0.06 ± 0.01 0.4 ± 0.06zymosan______________________________________
Table 6 shows that incubating AM for 18 hours with zymosan particles actually resulted in a reduced level of the oxidative responses. Incubating normal AM for 18 h resulted in an enhanced PMA-elicited CL responses (25,000 CPM) compared to the level of CL responses generated by freshly harvested AM (3,000 to 5,000 CPM). This phenomenon was referred to as "spontaneous priming" by Hayakawa et al., J. Leuk. Biol., 45:231-238 (1989), which is noted above.
In Vitro Priming of Normal AM with Bronchoalveolar Lavage Fluids (BAL) Produced from Zymosan Injected Rabbit
FIG. 1 shows that when freshly harvested AM from normal rabbits were incubated for three hours with BAL procured from rabbits injected with zymosan particles three days prior to harvesting cells, it primed normal AM for more than as 2-fold increase in PMA-elicited CL responses compared to untreated AM. In FIG. 1, rabbits were injected i.v. with 20 mg of zymosan in 2 ml of saline three days prior to extracting BAL. AM harvested from control rabbits were incubated for three hours at 37° C. with BAL preparations (50%) and were subsequently assayed for oxidative responses with PMA as the eliciting agent. It is noted that the level of oxidative burst by AM primed in vitro with BAL was much lower compared to in vivo priming with particle injection (see Table 1 above).
FIG. 2 shows that when AM from normal rabbits were incubated for 18 h with various concentrations of BAL fluids procured from zymosan injected rabbits, BAL fluids primed normal AM for as high as a 15-fold increase in latex elicited CL responses compared to that observed with untreated AM. In FIG. 2, BAL was extracted from rabbits two days after i.v. injection with 20 mg of zymosan. AM harvested from control rabbits were incubated with various concentrations of BAL for 18 hours at 37° C. and subsequently assayed for CL responses with latex as the eliciting agent. FIG. 2 shows that incubation of normal AM with lavage fluids procured from normal rabbits did not prime normal AM.
FIGS. 1 and 2 indicate that BAL fluids of zymosan-injected rabbits contain a macrophage priming factor (e.g., a cytokine) capable of priming macrophages that have not been exposed to particles. Only the BAL fluids of zymosan-injected rabbits contained a macrophage priming factor(s) that can prime normal AM in vitro. It is anticipated that the macrophage priming factor can be isolated and administered to patients instead of the phagocytosable particles to achieve the short duration priming effect shown in the data above. Hence, patients would be provided (e.g., by injection (intravenous, intratracheal, intraperitoneal, intramuscular, subcutaneous etc.), aerosol, or other means such as suppository, oral or nasal delivery, etc.) with a preparation containing the macrophage priming factor so that the macrophages in that patient could be primed for enhanced killing potential a certain number of days after such administration. It was observed that the macrophage priming factor present in BAL is relatively unstable and that about 50% of its activity is lost on storage at -60° C. over a 15-day period.
3. Applications
The important points discovered in the above experiments were: (1) the injection of adult rabbits with particulate preparations (zymosan, latex, or HK-BCG) of phagocytosable size prime AM in vivo in 1 to 4 days to give a very large oxidative burst when elicited in vitro with PMA, Op-zym or latex; (2) AM cannot be primed in vitro with the particulate preparations used; (3) AM are not primed in vivo by injecting large non-phagocytosable particle preparations; and (4) normal AM are primed in vitro with BAL procured from zymosan injected rabbits.
It is of particular interest that the magnitude of the elicited oxidative burst observed in the experiments of AM primed by i.v. injection of particulate preparations was equal to the maximal priming achieved three weeks after immunization with heat-killed BCG in oil (See, Chida et al., Infect. Immun.,55:1476-1483 (1987), Giridhar et al., J. Leuk. Biol., 49:442-448 (1991), and Hayakawa et al., J. Leuk. Biol., 45:231-238 (1989)). This level of response is indeed impressive because it represents more than a 100-fold increase in the capacity of AM to generate oxygen radicals as compared to resident AM from normal animals when elicited in vitro. This response is markedly different from classical T cell-mediated priming of macrophages in that the post-injection interval is only two to three days before maximal priming is observed.
The fact that AM cannot be primed in vitro with the particulate preparations used is of particular interest. This suggests that a second cell type may be involved in the priming of AM. A requirement of a particle of phagocytosable size is also notable. We were unable to induce any detectable priming of AM with non-phagocytosable latex particles. The requirement that particles must be of phagocytosable size suggests that phagocytosis of the injected particulates triggered the production of some macrophage-derived cytokine that activated a secondary cell type, such as a lymphoid, which is ultimately responsible for production of a priming factor(s). In this regard, either interleukin-1 or tumor necrosis factor could be candidates for activating the cell that ultimately synthesizes a priming factor(s). The observation that the lavage fluid obtained from particulate-injected rabbits primed normal AM in vitro (FIGS. 1 and 2) indicates a priming factor(s) accumulates in the lungs of injected rabbits.
The priming mechanism discovered, which has a rapid and short term, represents a non-specific form of a cell-mediated defense system. The potential of more than a 100-fold increase in the oxidative responses of lung macrophages and the associated killing capacity will have a highly beneficial effect in controlling lung infections, as well as other infections, under circumstances in which classical cell-mediated immunity does not have time to develop.
It is anticipated that in situations where patients who are about to undergo a planned surgery, or where soldiers are about to undergo a planned invasion or encounter biological weaponry, or in any other situation contagion will be encountered, a person could be provided with either preparations of phagocytosable particles or preparations including a macrophage priming factor one to four days, and more preferably two to three days, prior to the event.
The administration of the particles could be by injection, inhalation of an aerosolized dose, or by other suitable means.
In view of the particle preparations which were effective in priming the macrophages for significantly enhanced activity in rabbits, a suitable dose range for administration to human beings would be between 0.5 and 2 mg per kg of body weight. These estimations are based on the rabbit data that would produce about 75% of the maximal response. It is expected that higher dosages may be possible. Providing enough particles for the maximal response would be a goal. It is critical that the particulates used for priming of macrophages be phagocytosable (e.g., between 0.3 and 5 μm in diameter). In view of the results above, almost any type of particle would be suitable for quickly priming macrophages to an enhanced killing potential. It is preferred that the particles be biodegradable. For example, suitable biodegradable particles would include: biodegradable microspheres that are compounds of L-lactic acid/glycolic acid homo- and co-polymers (see, Tabata et al., J. Biomed. Mat. Res. 22:837-858 (1988)); gelatin particles (cross-linked); degradable starch complexes; biodegradable hydrogel such as poly(2-hydroxy-ethyl-L-glutamine) (PHEG) (see, Merchant et al., J. Biomed Mat. Res. 17:301-325 (1983)); hydroxybutyrate-hydroxyvalerate copolymers (see, Yasin et al., Biomaterials 13:9-16 (1992)); concanavalin A; colloidal particles of organic origin; degradable polyesters including block copolymer poly(ethylene succinate)-b-poly(ethylene glycol) (PES/PEG) (see, Albertsson et al., Acta Polymerica 30:95-104 (1988)); chitin; and cellulose. If biodegradable particles are used, they should remain relatively intact in the body for the 1-4 days required optimum short-term priming of macrophages.
A major point of interest is that the interval required for maximal particle-induced priming coincides with the 3- to 4-day interval commonly observed as the period between bacterial contamination, colonization, and apparent infection following surgery. If priming of macrophages could be achieved during this interval, the risk of infection may be greatly reduced. Hence, patients which have been exposed to contagion (viruses or bacteria) could be provided with a suspension phagocytosable particles so that in the short term, the patient's macrophages could be primed for enhanced killing potential within a short time period (1-4 days).
There are two lines of rationale that support the proposition that a macrophage priming system might be helpful to cancer patients. First, it has been established that some tumors are destroyed by activated macrophages, especially sarcomas. Second, some tumors of lymphoid cell origin cause a marked immunodepression which can result in severe opportunistic infections. Hence, a system like that which has been disclosed which primes macrophages to a high level of anti-tumor activity as well as anti-microbial activity could have beneficial effects in such patients. In addition, the macrophage priming capability of the inventive system will be useful in patients suffering from the acquired immune difficiency syndrome (AIDS). AIDS and cancer patients have increased susceptibility to secondary infections and their macrophage system is usually preserved until very late stages in their disease. Therefore, this macrophage augmentation effect should be extremely useful in preventing and treating secondary and opportunistic infections. As the effects last one week and are expected to be non-toxic to tissue cells, the administration may be repeated at monthly intervals for both cancer and AIDS patients.
Particle preparations may be administered by intravenous or intraperitoneal injection. The preparations may be prepared in saline as well as conventional buffers to render the injectable particle suspensions isotonic.
Aerosol delivery of the particles might also be used (e.g. via a nebulizer or metered dose inhaler). A chief advantage of aerosolization of the particles would be the non-invasive delivery procedure. If the particles are formulated into a metered dose inhaler (MDI) for aerosol delivery to the lungs, it will need to be dispersed in a propellant and packaged in a canister under pressure. The propellant could be any or a combination of the commonly used freons or CFCs, such as CCl 3 F (Freon 11 or CFC-11), CCl 2 F 2 (Freon 12 or CFC-12), and CClF 2 -CClF 2 (Freon 114 or CFC-114). However, there has recently been much emphasis on using more ozone friendly propellants such as 1,1,1,2-tetrafluoroethane (HFC-134a) and propellant 227, hydrocarbons (propane, butane, isobutane, etc.), fluorocarbons (perfluoropentane), dimethyl ether, or the like, in MDI applications and any of these gases or combinations thereof could be used. As with almost all MDI applications, the propellant typically constitutes over 90% by weight of the composition mixture. Surfactants such as oleic acid, lecithin, sorbitan trioleate, and the like, might also be included for lubricating the metering valve and aiding in dispersing the particles within the mixture.
As discussed above, alternative preparations for short term priming of macrophages would include the macrophage priming factor released by cells in response to encountering the phagocytosable particles. As shown in FIGS. 1 and 2, a macrophage priming factor exists in BAL fluids from animals exposed to phagocytosable particles in vivo two or three days prior to harvesting AM. This macrophage priming factor could be obtained from fluids in animals pretreated with phagocytosable particles or by recombinant or other suitable techniques. Preparations containing the macrophage priming factor, similar to the particle preparations described above, could be prepared for delivery by aerosol, i.v. or i.p or i.t. injection, or by other suitable means. The macrophage priming factor would be dissolved or dispersed in a pharmaceutically acceptable carrier fluid or gas or binder or elixir which would facilitate providing the macrophage priming factor to the patient.
While the invention has been described in terms of its preferred embodiments, those skilled in the art will recognize that the invention can be practiced with modification within the spirit and scope of the appended claims.
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A non-specific host defense cell augmentation technique for enhanced microorganism killing utilizes any phagocytosable, biocompatible particle to prime macrophages for enhanced oxidative response and bacterial killing. Patients can have the benefits of primed macrophages in one to four days, and experiments have demonstrated over a 100-fold increase in oxidative potential within this time period. The oxidative response and killing potential is non-immunospecific, meaning not one organism, not a vaccine, and broadly applicable simultaneously to bacteria and viruses as well as tumor cells. The effects have been demonstrated to have a seven day duration indicating non-tissue toxic residual effects and potential for repeated use at monthly intervals.
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This application claims benefit of 60/249,930, filed Nov. 17, 2000.
FIELD OF THE INVENTION
This invention relates to novel couplers for use in hair coloring compositions comprising one or more oxidative hair coloring agents in combination with one or more oxidizing agents. The invention also relates to hair coloring compositions of these novel couplers and to coloring or dyeing of hair using compositions containing these couplers.
BACKGROUND OF THE INVENTION
Coloration of hair is a procedure practiced from antiquity employing a variety of means. In modern times, the most extensively used method employed to color hair is to color hair by an oxidative dyeing process employing hair coloring systems utilizing one or more oxidative hair coloring agents in combination with one or more oxidizing agents.
Most commonly a peroxy oxidizing agent is used in combination with one or more oxidative hair coloring agents, generally small molecules capable of diffusing into hair and comprising one or more primary intermediates and one or more couplers. In this procedure, a peroxide material, such as hydrogen peroxide, is employed to activate the small molecules of primary intermediates so that they react with couplers to form larger sized compounds in the hair shaft to color the hair in a variety of shades and colors.
A wide variety of primary intermediates and couplers have been employed in such oxidative hair coloring systems and compositions. Among the primary intermediates employed there may be mentioned p-phenylenediamine, p-toluenediamine, p-aminophenol, 4-amino-3-methylphenol, and as couplers there may be mentioned resorcinol, 2-methylresorcinol, 3-aminophenol, and 5-amino-2-methyl phenol. A majority of the shades have been produced with dyes based on p-phenylenediamine.
For providing an orange coloration to hair 2-methyl-5-aminophenol has been extensively used in combination with p-aminophenol as a primary intermediate. However, the resulting orange color on hair undergoes significant changes on exposure to light or shampooing. U.S. Pat. No. 4,065,255 and EP patent to publications EP 634165 A1 and EP 667143 A1 suggest the use of 2-methyl-5-N-hydroxyethylaminophenol, 2-methyl-5-alkylaminophenol and 2-methyl-5-aminophenol as couplers. Therefore, there is a need for new orange couplers for use in oxidative hair dyeing compositions and systems.
BRIEF SUMMARY OF THE INVENTION
This invention provides novel couplers of the formula (1):
wherein X is selected from halogen where the halogen is preferably Cl, Br or I; R 3 is selected from C 1 to C 2 alkyl and hydroxyethyl; and R, R 1 and R 2 are each independently selected from C 1 to C 22 alkyl or C 1 to C 22 mono or dihydroxyalkyl groups or two of R, R 1 and R 2 together with the nitrogen atom to which they are attached form a C 3 to C 6 cycloaliphatic or a C 3 to C 14 aromatic group, the cycloaliphatic or aromatic group optionally containing in their rings one or more hetero atoms selected from O, S and N atoms. These novel couplers are used to provide coloration to hair in which there is good dye uptake by the hair and provides shades or colors which are stable over a relatively long period of time. The novel couplers provide for dyeing of hair that provides color or shades that possess good wash fastness and do not undergo the significant changes on exposure to light or shampooing as experienced with 2-methyl-5-aminophenol.
DETAILED DESCRIPTION OF THE INVENTION
Preferred coupler compounds of this invention are those of formula (1)
wherein X is Cl, Br or I; R 3 is methyl, ethyl or hydroxyethyl; and two of R, R 1 and R 2 together with the nitrogen atom to which they are attached form an C 3 to C 6 cycloaliphatic or C 3 to C 6 aromatic group optionally containing in the ring another N atom.
Especially preferred couplers of this invention are the following compounds:
1-[2-(3-hydroxy-4-methyl-phenylamino)-ethyl]-3 methyl 3-H-imidazol-1-ium chloride;
1-[2-(3-hydroxy-4-ethyl-phenylamino)-ethyl]-3 methyl 3-H-imidazol-1-ium chloride;
1-[2-(3-hydroxy-4-hydroxyethyl-phenylamino)-ethyl]-3 methyl 3-H-imidazol-1-ium chloride;
1-[2-(3-hydroxy-4-methyl-phenylamino)-ethyl]-3 methyl 3-H-imidazol-1-ium bromide;
1-[2-(3-hydroxy-4-methyl-phenylamino)-ethyl]-3 methyl 3-H-imidazol-1-ium iodide;
1-[2-(3-hydroxy-4-ethyl-phenylamino)-ethyl]-3 methyl 3-H-imidazol-1-ium propyl sulfate;
N-[2-(3-hydroxy-4-methyl-phenylamino)-ethyl-N′-methyl-piperidinium chloride;
N-[2-(3-hydroxy-4-ethyl-phenylamino)-ethyl-N′-methyl-piperidinium chloride;
N-[2-(3-hydroxy-4-hydroxyethyl-phenylamino)-ethyl-N′-methyl-piperidinium chloride;
N-[2-(3-hydroxy-4-methyl-phenylamino)-ethyl-N′-methyl-piperidinium bromide; and
N-[2-(3-hydroxy-4-methyl-phenylamino)-ethyl-N′-methyl-piperidinium iodide.
The compounds of formula (1) of this invention are readily prepared according to the following reaction sequence.
In the reaction sequence a solution of an aminophenol of formula (2) in tetrahydrofuran (THF) is added to a solution of haloacetyl chloride to produce a compound of formula (5). Treatment of the compound of formula (5) with a borane-THF complex produces a compound of formula (6) and reaction of this compound of formula (6) with a quaternization reagent of the formula N(R 1 )(R 2 )(R 3 ) produces a compound of formula (1).
SYNTHESIS EXAMPLES 1-10
Employing the appropriate aminophenol, haloacetylchloride, and N(R1)(R2)(R3) quaternization reagent in the forgoing described synthesis procedure the following coupler compounds of this invention are prepared.
1-[2-(3-hydroxy-4-methyl-phenylamino)-ethyl]-3 methyl 3-H-imidazol-1-ium chloride;
N-[2-(3-hydroxy-4-methyl-phenylamino)-ethyl-N′-methyl-piperidinium chloride;
1-[2-(3-hydroxy-4-ethyl-phenylamino)-ethyl]-3 methyl 3-H-imidazol-1-ium chloride;
1-[2-(3-hydroxy-4-hydroxyethyl-phenylamino)-ethyl]-3 methyl 3-H-imidazol-1-ium chloride;
1-[2-(3-hydroxy-4-methyl-phenylamino)-ethyl]-3 methyl 3-H-imidazol-1-ium bromide;
1-[2-(3-hydroxy-4-methyl-phenylamino)-ethyl]-3 methyl 3-H-imidazol-1-ium iodide;
N-[2-(3-hydroxy-4-ethyl-phenylamino)-ethyl-N′-methyl-piperidinium chloride;
N-[2-(3-hydroxy-4-hydroxyethyl-phenylamino)-ethyl-N′-methyl-piperidinium chloride;
N-[2-(3-hydroxy-4-methyl-phenylamino)-ethyl-N′-methyl-piperidinium bromide; and
N-[2-(3-hydroxy-4-methyl-phenylamino)-ethyl-N′-methyl-piperidinium iodide.
Hair coloring compositions of this invention can contain the novel couplers of this invention as the sole coupler or can also contain other couplers in combination with primary intermediates.
For hair coloring compositions of this invention, there may be used one or more suitable primary intermediates in combination with the novel couplers of this invention. Suitable primary intermediates include, for example,
p-phenylenediamine derivatives such as: benzene-1,4-diamine (commonly known as p-phenylenediamine), 2-methyl-benzene-1,4-diamine, 2-chloro-benzene-1,4-diamine, N-phenyl-benzene-1,4-diamine, N-(2-ethoxyethyl)benzene-1,4-diamine, 2-[(4-amino-phenyl)-(2-hydroxy-ethyl)-amino]-ethanol, (commonly known as N,N-bis(2-hydroxyethyl)-p-phenylenediamine) (2,5-diamino-phenyl)-methanol, 1-(2,5-diamino-phenyl)-ethanol, 2-(2,5-diamino-phenyl)-ethanol, N-(4-aminophenyl)benzene-1,4-diamine, 2,6-dimethyl-benzene-1,4-diamine, 2-isopropyl-benzene-1,4-diamine, 1-[(4-aminophenyl)amino]-propan-2-ol, 2-propyl-benzene-1,4-diamine, 1,3-bis[(4-aminophenyl)(2-hydroxyethyl)amino]propan-2-ol, N 4 ,N 4 ,2-trimethylbenzene-1,4-diamine, 2-methoxy-benzene-1,4-diamine, 1-(2,5-diaminophenyl)ethane-1,2-diol, 2,3-dimethyl-benzene-1,4-diamine, N-(4-amino-3-hydroxy-phenyl)-acetamide, 2,6-diethylbenzene-1,4-diamine, 2,5-dimethylbenzene-1,4-diamine, 2-thien-2-ylbenzene-1,4-diamine, 2-thien-3-ylbenzene-1,4-diamine, 2-pyridin-3-ylbenzene-1,4-diamine, 1,1′-biphenyl-2,5-diamine, 2-(methoxymethyl)benzene-1,4-diamine, 2-(aminomethyl)benzene-1,4-diamine, 2-(2,5-diaminophenoxy)ethanol, N-[2-(2,5-diaminophenoxy)ethyl]-acetamide, N,N-dimethylbenzene-1,4-diamine, N,N-diethylbenzene-1,4-diamine, N,N-dipropylbenzene-1,4-diamine, 2-[(4-aminophenyl)(ethyl)amino]ethanol, 2-[(4-amino-3-methyl-phenyl)-(2-hydroxy-ethyl)-amino]-ethanol, N-(2-methoxyethyl)-benzene-1,4-diamine,-[(4-aminophenyl)amino]propan-1-ol, 3-[(4-aminophenyl)-amino]propane-1,2-diol, N-{4-[(4-aminophenyl)amino]butyl}benzene-1,4-diamine, and 2-[2-(2-{2-[(2,5-diaminophenyl)-oxy]ethoxy}ethoxy)ethoxy]benzene-1,4-diamine;
p-aminophenol derivatives such as: 4-amino-phenol (commonly known as p-aminophenol), 4-methylamino-phenol, 4-amino-3-methyl-phenol, 4-amino-2-hydroxymethyl-phenol, 4-amino-2-methyl-phenol, 4-amino-2-[(2-hydroxy-ethylamino)-methyl]-phenol, 4-amino-2-methoxymethyl-phenol, 5-amino-2-hydroxy-benzoic acid, 1-(5-amino-2-hydroxy-phenyl)-ethane-1,2-diol, 4-amino-2-(2-hydroxy-ethyl)-phenol, 4-amino-3-(hydroxymethyl)phenol, 4-amino-3-fluoro-phenol, 4-amino-2-(aminomethyl)-phenol, and 4-amino-2-fluoro-phenol;
o-aminophenol derivatives such as: 2-amino-phenol (commonly known as o-aminophenol), 2,4-diaminophenol, 2-amino-5-methyl-phenol, 2-amino-6-methyl-phenol, N-(4-amino-3-hydroxy-phenyl)-acetamide, and 2-amino-4-methyl-phenol; and
heterocyclic derivatives such as: pyrimidine-2,4,5,6-tetramine (commonly known as 2,4,5,6-tetraaminopyridine), 1-methyl-1H-pyrazole-4,5-diamine, 2-(4,5-diamino-1H-pyrazol-1-yl)ethanol, N 2 ,N 2 -dimethyl-pyridine-2,5-diamine, 2-[(3-amino-6-methoxypyridin-2-yl)amino]ethanol, 6-methoxy-N 2 -methyl-pyridine-2,3-diamine, 2,5,6-triaminopyrimidin-4(1H)-one, pyridine-2,5-diamine, 1-isopropyl-1H-pyrazole-4,5-diamine, 1-(4-methylbenzyl)-1H-pyrazole-4,5-diamine, 1-(benzyl)-1H-pyrazole-4,5-diamine and 1-(4-chlorobenzyl)-1H-pyrazole-4,5-diamine.
The couplers of formula (1) of this invention may be used with any suitable coupler(s) in hair coloring compositions or systems of this invention.
Suitable known couplers include, for example:
phenols, resorcinol and naphthol derivatives such as: naphthalene-1,7-diol, benzene-1,3-diol, 4-chlorobenzene-1,3-diol, naphthalen-1-ol, 2-methyl-naphthalen-1-ol, naphthalene-1,5-diol, naphthalene-2,7-diol, benzene-1,4-diol, 2-methyl-benzene-1,3-diol, 7-amino-4-hydroxy-naphthalene-2-sulfonic acid, 2-isopropyl-5-methylphenol, 1,2,3,4-tetrahydro-naphthalene-1,5-diol, 2-chloro-benzene-1,3-diol, 4-hydroxy-naphthalene-1-sulfonic acid, benzene-1,2,3-triol, naphthalene-2,3-diol, 5-dichloro-2-methylbenzene-1,3-diol, 4,6-dichlorobenzene-1,3-diol, and 2,3-dihydroxy-[1,4]naphthoquinone;
m-phenylenediamines such as: 2,4-diaminophenol, benzene-1,3-diamine, 2-(2,4-diamino-phenoxy)-ethanol, 2-[(3-amino-phenyl)-(2-hydroxy-ethyl)-amino]-ethanol, 2-mehyl-benzene-1,3-diamine, 2-[[2-(2,4-diamino-phenoxy)-ethyl]-(2-hydroxy-ethyl)-amino]-ethanol, 4-{3-[(2,4-diaminophenyl)oxy]propoxy}benzene-1,3-diamine, 2-(2,4-diamino-phenyl)-ethanol, 2-(3-amino-4-methoxy-phenylamino)-ethanol, 4-(2-amino-ethoxy)-benzene-1,3-diamine, (2,4-diamino-phenoxy)-acetic acid, 2-[2,4-diamino-5-(2-hydroxy-ethoxy)-phenoxy]-ethanol, 4-ethoxy-6-methyl-benzene-1,3-diamine, 2-(2,4-diamino-5-methyl-phenoxy)-ethanol, 4,6-dimethoxy-benzene-1,3-diamine, 2-[3-(2-hydroxy-ethylamino)-2-methyl-phenylamino]-ethanol, 3-(2,4-diamino-phenoxy)-propan-1-ol, N-[3-(dimethylamino)phenyl]urea, 4-methoxy-6-methylbenzene-1,3-diamine, 4-fluoro-6-methylbenzene-1,3-diamine, 2-({3-[(2-hydroxyethyl)amino]-4,6-dimethoxyphenyl}-amino)ethanol, 3-(2,4-diaminophenoxy)-propane-1,2-diol, 2-[2-amino-4-(methylamino)-phenoxy]ethanol, 2-[(5-amino-2-ethoxy-phenyl)-(2-hydroxy-ethyl)-amino]-ethanol, 2-[(3-aminophenyl)amino]ethanol, N-(2-aminoethyl)benzene-1,3-diamine, 4-{[(2,4-diamino-phenyl)oxy]methoxy}-benzene-1,3-diamine, and 2,4-dimethoxybenzene-1,3-diamine;
m-aminophenols such as: 3-amino-phenol, 2-(3-hydroxy-4-methyl-phenylamino)-acetamide, 2-(3-hydroxy-phenylamino)-acetamide, 5-amino-2-methyl-phenol, 5-(2-hydroxy-ethylamino)-2-methyl-phenol, 5-amino-2,4-dichloro-phenol, 3-amino-2-methyl-phenol, 3-amino-2-chloro-6-methyl-phenol, 5-amino-2-(2-hydroxy-ethoxy)-phenol, 2-chloro-5-(2,2,2-trifluoro-ethylamino)-phenol, 5-amino-4-chloro-2-methyl-phenol, 3-cyclopentylamino-phenol, 5-[(2-hydroxyethyl)amino]-4-methoxy-2-methylphenol, 5-amino-4-methoxy-2-methylphenol, 3-(dimethylamino)phenol, 3-diethylamino)phenol, 5-amino-4-fluoro-2-methylphenol, 5-amino-4-ethoxy-2-methylphenol, 3-amino-2,4-dichloro-phenol, 3-[(2-methoxyethyl)amino]phenol, 3-[(2-hydroxyethyl)amino]phenol, 5-amino-2-ethyl-phenol, 5-amino-2-methoxyphenol, 5-[(3-hydroxypropyl)amino]-2-methylphenol, 3-[(3-hydroxy-2-methylphenyl)-amino]propane-1,2-diol, and 3-[(2-hydroxyethyl)amino]-2-methylphenol; and
heterocyclic derivatives such as: 3,4-dihydro-2H-1,4-benzoxazin-6-ol, 4-methyl-2-phenyl-2,4-dihydro-3H-pyrazol-3-one, 6-methoxyquinolin-8-amine, 4-methylpyridine-2,6-diol, 2,3-dihydro-1,4-benzodioxin-5-ol, 1,3-benzodioxol-5-ol, 2-(1,3-benzodioxol-5-ylamino)ethanol, 3,4-dimethylpyridine-2,6-diol, 5-chloropyridine-2,3-diol, 2,6-dimethoxypyridine-3,5-diamine, 1,3-benzodioxol-5-amine, 2-{[3,5-diamino-6-(2-hydroxy-ethoxy)-pyridin-2-yl]oxy}-ethanol, 1H-indol-4-ol, 5-amino-2,6-dimethoxypyridin-3-ol, 1H-indole-5,6-diol, 1H-indol-7-ol, 1H-indol-5-ol, 1H-indol-6-ol, 6-bromo-1,3-benzodioxol-5-ol, 2-aminopyridin-3-ol, pyridine-2,6-diamine, 3-[(3,5-diaminopyridin-2-yl)oxy]propane-1,2-diol, 5-[(3,5-diaminopyridin-2-yl)oxy]pentane-1,3-diol, 1H-indole-2,3-dione, indoline-5,6-diol, 3,5-dimethoxypyridine-2,6-diamine, 6-methoxypyridine-2,3-diamine, and 3,4-dihydro-2H-1,4-benzoxazin-6-amine.
Preferred primary intermediates include:
p-phenylenediamine derivatives such as: 2-methyl-benzene-1,4-diamine, benzene-1,4-diamine, 1-(2,5-diamino-phenyl)-ethanol, 2-(2,5-diamino-phenyl)-ethanol, N-(2-methoxyethyl)benzene-1,4-diamine, 2-[(4-amino-phenyl)-(2-hydroxy-ethyl)-amino]-ethanol, and 1-(2,5-diaminophenyl)ethane-1,2-diol;
p-aminophenol derivatives such as 4-amino-phenol, 4-methylamino-phenol, 4-amino-3-methyl-phenol, 4-amino-2-methoxymethyl-phenol, and 1-(5-amino-2-hydroxy-phenyl)-ethane-1,2-diol;
o-aminophenol derivatives such as: 2-amino-phenol, 2-amino-5-methyl-phenol, 2-amino-6-methyl-phenol, N-(4-amino-3-hydroxy-phenyl)-acetamide, and 2-amino-4-methyl-phenol;
heterocyclic derivatives such as: pyrimidine-2,4,5,6-tetramine, 1-methyl-1H-pyrazole-4,5-diamine, 2-(4,5-diamino-1H-pyrazol-1-yl)ethanol, 1-(4-methylbenzyl)-1H-pyrazole-4,5-diamine, 1-(benzyl)-1H-pyrazole-4,5-diamine and N 2 , N 2 -dimethyl-pyridine-2,5-diamine.
Preferred couplers include:
phenols, resorcinol and naphthol derivatives such as: naphthalene-1,7-diol, benzene-1,3-diol, 4-chlorobenzene-1,3-diol, naphthalene-1-ol, 2-methyl-naphthalen-1-ol, naphthalene-1,5-diol, naphthalene-2,7-diol, benzene-1,4-diol, 2-methyl-benzene-1,3-diol, and 2-isopropyl-5-methylphenol;
m-phenylenediamines such as: benzene-1,3-diamine, 2-(2,4-diamino-phenoxy)-ethanol, 4-{3-[(2,4-diaminophenyl)oxy]propoxy}benzene-1,3-diamine, 2-(3-amino-4-methoxy-phenylamino)-ethanol, 2-[2,4-diamino-5-(2-hydroxy-ethoxy)-phenoxy]-ethanol, and 3-(2,4-diamino-phenoxy)-propan-1-ol;
m-aminophenols such as: 3-amino-phenol, 5-amino-2-methyl-phenol, 5-(2-hydroxy-ethylamino)-2-methyl-phenol, and 3-amino-2-methyl-phenol; and
heterocyclic derivatives such as: 3,4-dihydro-2H-1,4-benzoxazin-6-ol, 4-methyl-2-phenyl-2,4-dihydro-3H-pyrazol-3-one, 1,3-benzodioxol-5-ol, 1,3-benzodioxol-5-amine, 1H-indol-4-ol, 1H-indole-5,6-diol, 1H-indol-7-ol, 1H-indol-5-ol, 1H-indol-6-ol, 1H-indole-2,3-dione, pyridine-2,6-diamine, and 2-aminopyridin-3-ol.
Most preferred primary intermediates include:
p-phenylenediamine derivatives such as: 2-methyl-benzene-1,4-diamine, benzene-1,4-diamine, 2-(2,5-diamino-phenyl)-ethanol, 1-(2,5-diamino-phenyl)-ethanol, and 2-[(4-amino-phenyl)-(2-hydroxy-ethyl)-amino]-ethanol;
p-aminophenol derivatives such as: 4-amino-phenol, 4-methylamino-phenol, 4-amino-3-methyl-phenol, and 1-(5-amino-2-hydroxy-phenyl)-ethane-1,2-diol;
o-aminophenols such as: 2-amino-phenol, 2-amino-5-methyl-phenol, 2-amino-6-methyl-phenol, and N-(4-amino-3-hydroxy-phenyl)-acetamide; and
heterocyclic derivatives such as: pyrimidine-2,4,5,6-tetramine, 2-(4,5-diamino-1H-pyrazol-1-yl)ethanol, 1-(4-methylbenzyl)-1H-pyrazole-4,5-diamine, and 1-(benzyl)-1H-pyrazole-4,5-diamine.
Most preferred couplers include:
phenols, resorcinol and naphthol derivatives such as: benzene-1,3-diol, 4-chlorobenzene-1,3-diol, naphthalen-1-ol, 2-methyl-naphthalen-1-ol, and 2-methyl-benzene-1,3-diol;
m-phenylenediamine such as: 2-(2,4-diamino-phenoxy)-ethanol, 2-(3-amino-4-methoxy-phenylamino)-ethanol, 2-[2,4-diamino-5-(2-hydroxy-ethoxy)-phenoxy]-ethanol, and 3-(2,4-diamino-phenoxy)-propan-1-ol;
m-aminophenols such as: 3-amino-phenol, 5-amino-2-methyl-phenol, 5-(2-hydroxy-ethylamino)-2-methyl-phenol, and 3-amino-2-methyl-phenol; and
heterocyclic derivatives such as: 3,4-dihydro-2H-1,4-benzoxazin-6-ol, 4-methyl-2-phenyl-2,4-dihydro-3H-pyrazol-3-one, 1H-indol-6-ol, and 2-aminopyridin-3-ol.
Understandably, the coupler compounds and the primary intermediate compounds, as well as the other dye compounds, in so far as they are bases, can be used as free bases or in the form of their physiologically compatible salts with organic or inorganic acids, such as hydrochloric acid or sulfuric acid, or, in so far as they have aromatic OH groups, in the form of their salts with bases, such as alkali phenolates.
The total amount of the combination of dye precursors (e.g., primary intermediate and coupler compounds) in the hair coloring compositions or systems of this invention is generally from about 0.001 to about 10, preferably from about 0.02 to about 10, and most preferably from about 0.2 to about 6.0 weight percent based on the total weight of the hair coloring composition. The primary intermediate and coupler compounds are generally used in equivalent amounts. However, it is possible to use the primary intermediate compounds in either excess or deficiency, i.e., a molar ratio of primary intermediate to coupler generally ranging from about 5:1 to about 1:5.
The hair coloring compositions of this invention will contain the couplers of this invention in an effective coloring amount, generally in an amount of from about 0.001 to about 6 weight percent by weight of the hair dye composition, preferably from about 0.01 to about 3.5 weight percent. Other couplers, when present, are typically present in an amount such that in aggregate the concentration of couplers in the composition is from about 0.01 to about 6 weight percent. The primary intermediate(s) is present in an effective dyeing concentration generally an amount of from about 0.001 to about 6.0 weight percent by weight of the hair dye composition, preferably from about 0.01 to about 3.5 weight percent. Any suitable carrier or vehicle, generally an aqueous or hydroalcoholic solution, can be employed, preferably an aqueous solution. The carrier or vehicle will generally comprise up to about 40 weight percent.
The hair coloring compositions of this invention may contain one or more cationic, anionic or amphoteric surface active agents, perfumes, antioxidants, sequestering agents, thickening agents, alkalizing or acidifying agents, and other dyeing agents.
The compositions of the present invention are used by admixing them with a suitable oxidant, which reacts with the hair dye precursors to develop the hair dye. Any suitable peroxide providing agent can be employed in the coloring compositions of this invention, particularly hydrogen peroxide (H 2 O 2 ) or precursors therefor. Also suitable are urea peroxide, sodium perborate, sodium percarbonate, and melamine peroxide.
Moreover, cosmetic additive ingredients, which are commonly used in compositions for coloring hair, can be used in the hair coloring compositions according to the invention, for example antioxidants, such as ascorbic acid, thioglycolic acid or sodium sulfite, and perfume oils, complex formers, wetting agents, emulsifiers, thickeners and care materials.
The form of the hair coloring compositions according to the invention can be, for example, a solution, especially an aqueous or aqueous-alcoholic solution. However, the form that is particularly preferred is a cream, gel or an emulsion. Its composition is a mixture of the dye ingredients with the conventional cosmetic additive ingredients suitable for the particular preparation.
Conventional cosmetic additive ingredients in solutions, creams, emulsion or gels include, for example:
Solvents: In addition to water, solvents that can be used are lower alkanols (e.g., ethanol, propanol, isopropanol); polyols (e.g., carbitols, propylene glycol, glycerin). Under suitable processing, higher alcohols, such as cetyl alcohol, are suitable organic solvents, provided they are first liquified by melting, typically at low temperature (50 to 80° C.), before incorporation of other, usually lipophilic, materials. See WO 98/27941 (section on diluents) incorporated by reference.
Anionic and Nonionic Surfactants: These materials are from the classes of anionic, cationic, amphoteric or nonionic surfactant compounds, such as fatty alcohol sulfates, ethoxylated fatty alcohol sulfates, alkylsulfonates, alkylbenzensulfonates, alkyltrimethylammonium salts, alkylbetaines, ethoxylated fatty alcohols, ethoxylated nonylphenols, fatty acid alkanol amides and ethoxylated fatty acid esters. They are included for various reasons, e.g., to assist in thickening, for forming emulsions, to help in wetting hair during application of the hair dye composition, etc. Suitable materials are alkyl sulfates, ethoxylated alkyl sulfates, alkyl glyceryl ether sulfonates, methyl acyl taurates, acyl isethionates, alkyl ethoxy carboxylates, fatty acid mono- and diethanolamides. Reference is made to WO 98/52523 published Nov. 26, 1998 and incorporated herein by reference.
Thickeners: Suitable thickeners include such as higher fatty alcohols, starches, cellulose derivatives, petrolatum, paraffin oil, fatty acids and anionic and nonionic polymeric thickeners based on polyacrylic and polyurethane polymers. Examples are hydroxyethyl cellulose, hydroxymethylcellulose and other cellulose derivatives, hydrophobically modified anionic polymers and nonionic polymers, particularly such polymers having both hydrophilic and hydrophobic moieties (i.e., amphiphilic polymers). Useful nonionic polymers include polyurethane derivatives such as PEG-150/stearyl alcohol/SDMI copolymer and PEG-150/stearyl alcohol SDMI copolymer. Other useful amphiphilic polymers are disclosed in U.S. Pat. No. 6,010,541 incorporated by reference. Examples of anionic polymers that can be used as thickeners are acrylates copolymer, acrylates/ceteth-20 methacrylates copolymer, acrylates/ceteth-20 itaconate copolymer, and acrylates/beheneth-25 acrylates copolymer. Aculyn® polymers sold by Rohm & Haas, as well as hair care materials, such as cationic resins, lanolin derivatives, cholesterol, pantothenic acids and betaine.
Alkalizing agents: Suitable materials that are used to increase pH of the hair dye compositions include ammonia, aminomethylpropanol, methylethanolamine, triethanolamine and ethanolamine.
Conditioners: Suitable materials include silicones and silicone derivatives; hydrocarbon oils; monomeric quaternary compounds, and quaternized polymers. Monomeric quaternary compounds are typically cationic compounds, but may also include betaines and other amphoteric and zwitterionic materials. Suitable monomeric quaternary compounds include behentrialkonium chloride, behentrimonium chloride, benzalkonium bromide or chloride, benzyl triethyl ammonium chloride, bis-hydroxyethyl tallowmonium chloride, C12-18 dialkyldimonium chloride, cetalkonium chloride, ceteartrimonium bromide and chloride, cetrimonium bromide, chloride and methosulfate, cetylpyridonium chloride, cocamidoproypl ethyldimonium ethosulfate, cocamidopropyl ethosulfate, coco-ethyldimonium ethosulfate, cocotrimonium chloride and ethosulfate, dibehenyl dimonium chloride, dicetyidimonium chloride, dicocodimonium chloride, dilauryl dimonium chloride, disoydimonium chloride, ditallowdimonium chloride, hydrogenated tallow trimonium chloride, hydroxyethyl cetyl dimonium chloride, myristalkonium chloride, olealkonium chloride, soyethomonium ethosulfate, soytrimonium chloride, stearalkonium chloride, and many other compounds. See WO 98/27941 incorporated by reference. Quaternized polymers are typically cationic polymers, but may also include amphoteric and zwitterionic polymers. Useful polymers are exemplified by polyquaternium-4, polyquaternium-6, polyquaternium-7, polyquaternium-8, polyquaternium-9, polyquaternium-10, polyquaternium-22, polyquaternium-32, polyquaternium-39, polyquaternium-44 and polyquaternium-47. Silicones suitable to condition hair are dimethicone, amodimethicone, dimethicone copolyol and dimethiconol. See also WO 99/34770 published Jul. 15, 1999, incorporated by reference, for suitable silicones. Suitable hydrocarbon oils would include mineral oil.
Natural ingredients: For example, protein derivatives, aloe, camomile and henna extracts.
Other adjuvants include acidulents to lower pH, buffers, chelating agents antioxidants, sequestrants, etc. These classes of materials and other species of materials in the classes referred to above but not specifically identified that are suitable are listed in the International Cosmetics Ingredient Dictionary and Handbook, (Eighth Edition) published by The Cosmetics, Toiletry, and Fragrance Association, incorporated by reference. In particular reference is made to Volume 2, Section 3 (Chemical Classes) and Section 4 (Functions) are useful in identifying a specific adjuvant/excipient to achieve a particular purpose or multipurpose.
The above-mentioned conventional cosmetic ingredients are used in amounts suitable for their purposes. For example the wetting agents and emulsifiers are used in concentrations of from about 0.5 to 30 percent by weight, the thickeners are used in an amount of from about 0.1 to 25 percent by weight and the hair care materials are used in concentrations of from about 0.1 to 5.0 percent by weight.
The hair coloring compositions according to the invention can be weakly acidic, neutral or alkaline according to their composition. The compositions typically have pH values of from 6.8 to 11.5. Their pH can be adjusted in the basic range with ammonia. Also, organic amines can be used for this purpose, including monoethanolamine and triethanolamine, or also inorganic bases, such as sodium hydroxide and potassium hydroxide. Inorganic or organic acids can be used for adjusting the pH in the acid range, for example phosphoric acid, acetic acid, citric acid or tartaric acid.
The hair coloring compositions of this invention will contain the couplers of this invention, alone or in combination with other couplers, in an effective coloring amount, generally in an amount of from about 0.01 to about 2.5 weight percent. Other couplers, when present will be present in an amount up to about 2.5 weight percent. The primary intermediate(s) will generally be present in an amount of from about 0.01 to about 3.5 weight percent. The molar ratio of primary intermediate to coupler will generally range from about 5:1 to about 1:5 and be employed in any suitable carrier or vehicle, generally an aqueous or hydroalcoholic solution, preferably an aqueous solution. The carrier or vehicle will generally comprise up to about 40 weight percent.
In order to use the oxidation hair coloring composition for dyeing hair one mixes the above-described hair coloring compositions according to the invention with an oxidizing agent immediately prior to use and applies a sufficient amount of the mixture to the hair, according to the hair abundance, generally from about 60 to 200 grams. Some of the adjuvants listed above (e.g., thickeners, conditoners, etc.) can be provided in the dye composition or the developer, or both, depending on the nature of the ingredients, possible interactions, etc., as is well known in the art.
Typically hydrogen peroxide, or its addition compounds with urea, melamine, sodium borate or sodium carbonate, can be used in the form of a 3 to 12 percent, preferably 6 percent, aqueous solution as the oxidizing agent for developing the hair dye. Oxygen can also be used as the oxidizing agent. If a 6 percent hydrogen peroxide solution is used as oxidizing agent, the weight ratio of hair coloring composition and oxidizing agent is 5:1 to 1:2, but preferably 1:1. The mixture of the oxidizing agent and the dye composition of the invention is allowed to act on the hair for about 10 to about 45 minutes, preferably about 30 minutes, at about 15 to 50° C., the hair is rinsed with water and dried. If necessary, it is washed with a shampoo and eventually after-rinsed with a weak organic acid, such as citric acid or tartaric acid. Subsequently the hair is dried.
The hair coloring composition according to the invention with a compound of formula (1) of this invention as coupler substances permits hair dyeing with outstanding color fastness, especially light fastness, fastness to washing and fastness to rubbing.
In general, a first composition of primary intermediate(s) and coupler(s) is prepared and then, at the time of use, the oxidizing agents, such as H 2 O 2 , is admixed therewith until an essentially homogenous composition is obtained which is applied to the hair to be dyed and permitted to remain in contact with the hair for a dyeing effective amount of time, generally for a period of from about 2 to 45, preferably about 2 to 30, minutes, after which the hair is rinsed, shampooed and dried. Optionally, a separate conditioning product may also be provided. Together the hair dye composition of the present invention comprising the hair dye coupler (1) and the developer comprising the oxidizing agent form a system for dyeing hair. This system may be provided as a kit comprising in a single package separate containers of the hair dye compositions, the developer, the optional conditioner or the hair treatment product, and instructions for use.
EXAMPLE 11
The following compositions shown in Table 1 can be used for dyeing Piedmont hair. The dyeing solution is mixed with 100 g 20 volume hydrogen peroxide. The resulting mixture is applied to the hair and permitted to remain in contact with the hair for 30 minutes. This dyed hair is then shampooed and rinsed with water and dried
TABLE I
Composition for Dyeing Hair
Ingredients
Range (wt %)
Weight (%)
Cocamidopropyl betaine
0-25
17.00
Monoethanolamine 1
0-15
2.00
Oleic Acid
2-22
0.75
Citric Acid
0-3
0.10
28% Ammonium hydroxide 1
0-15
5.00
Behentrimonium chloride
1-5
0.50
Sodium sulfite
0-1
0.10
EDTA
0-1
0.10
Erythorbic acid
0-1
0.40
Ethoxydiglycol
1-10
3.50
C11-15 Pareth-9 (Tergitol 15-S-9)
0.5-5
1.00
C12-15 Pareth-3 (Neodol 25-3)
0.25-5
0.50
Isopropanol
2-10
4.00
Propylene glycol
1-12
2.00
P-phenylenediamine 2
0-5
2 mmoles
N,N-Bis(hydroxyethyl)-p-phenylene
0-5
2 mmoles
diamine 2
3-Methyl-p-aminophenol 2
0-5
1 mmoles
p-Aminophenol 2
0-5
5 mmoles
Coupler of this invention
0.5-5
5 mmoles
5-Amino-2-Methyl Phenol
0-5
2 mmoles
2,4-Diaminophenoxyethanol
0-5
2 mmoles
Water
qs to 100.00
qs to 100.00
1 In the aggregate, these ingredients are in the range of 2 to 15% by weight.
2 At least one of these dye precursors is typically present.
Exemplary combinations of hair coloring components employing a coupler compound of formula (1) of this invention are show in combinations in Table 1 and in C1 to C126 in Table A. Reading down the columns in Table A, the Xes designate the dye compounds (including the novel couplers of the instant invention) that form illustratively suitable combinations of dyes that can be formulated according to the present invention. For example, in Combination No. C1 the novel couplers of the present invention (Row 1 of Table A) with X, R, R 1 , R 2 and R 3 are as defined hereinbefore, can be combined with p-toluene diamine and 2-amino-phenol. Especially preferred as the couplers of formula (1) of this invention in the combinations C1 to C126 of Table A are:
1-[2-(3-hydroxy-4-methyl-phenylamino)-ethyl]-3 methyl 3-H-imidazol-1-ium chloride;
1-[2-(3-hydroxy-4-ethyl-phenylamino)-ethyl]-3 methyl 3-H-imidazol-1-ium chloride;
1-[2-(3-hydroxy-4-hydroxyethyl-phenylamino)-ethyl]-3 methyl 3-H-imidazol-1-ium chloride;
1-[2-(3-hydroxy-4-methyl-phenylamino)-ethyl]-3 methyl 3-H-imidazol-1-ium bromide;
1-[2-(3-hydroxy-4-methyl-phenylamino)-ethyl]-3 methyl 3-H-imidazol-1-ium iodide;
N-[2-(3-hydroxy-4-methyl-phenylamino)-ethyl-N′-methyl-piperidinium chloride;
N-[2-(3-hydroxy-4-ethyl-phenylamino)-ethyl-N′-methyl-piperidinium chloride;
N-[2-(3-hydroxy-4-hydroxyethyl-phenylamino)-ethyl-N′-methyl-piperidinium chloride;
N-[2-(3-hydroxy-4-methyl-phenylamino)-ethyl-N′-methyl-piperidinium bromide; and
N-[2-(3-hydroxy-4-methyl-phenylamino)-ethyl-N′-methyl-piperidinium iodide.
TABLE A
DYE COMBINATIONS
Structure
IUPAC Name
Name
C1
C2
C3
C4
C5
C6
C7
C8
C9
C10
C11
C12
C13
C14
C15
3-Hydroxy-4-alkyl- phenylamino-ethyl-1- trialkyl-ammonium halide
3-Hydroxy-4-alkyl- phenylamino-ethyl-1- trialkyl-ammonium halide
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
2-Methyl-benzene- 1,4-diamine
p-Toluene-diamine
X
X
X
X
X
X
X
X
X
Benzene-1,4- diamine
p-Phenylene-diamine
X
X
X
X
X
X
2-[(4-Amino-phenyl)- (2-hydroxy-ethyl)- amino]-ethanol
N,N-Bis(2- hydroxyethyl)-p- phenylene-diamine
4-Amino-phenol
p-Aminophenol
4-Amino-3-methyl- phenol
3-Methyl-p- aminophenol
2-Amino-phenol
o-Aminophenol
X
X
Benzene-1,3-diol
Resorcinol
X
X
2-Methyl-benzene- 1,3-diol
2-Methyl-resorcinol
X
X
Naphthalen-1-ol
1-Naphthol
X
X
2-Methyl-naphthalen- 1-ol
2-Methyl-1-naphthol
X
X
2-(2,4-Diamino- phenoxy)-ethanol
2,4-Diamino- phenoxyethanol
X
X
Benzene-1,3- diamine
m-Phenylenediamine
X
3-Amino-phenol
m-Aminophenol
X
5-Amino-2-methyl- phenol
2-Hydroxy-4- aminotoluene
X
2-(4,5-Diamino- pyrazol-1-yl-ethanol
1-Hydroxyethyl-4,5- diamino-pyrazole
Structure
C16
C17
C18
C19
C20
C21
C22
C23
C24
C25
C26
C27
C28
C29
C30
C31
C32
C33
C34
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Structure
C35
C36
C37
C38
C39
C40
C41
C42
C43
C44
C45
C46
C47
C48
C49
C50
C51
C52
C53
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Structure
C54
C55
C56
C57
C58
C59
C60
C61
C62
C63
C64
C65
C66
C67
C68
C69
C70
C71
C72
C73
C74
C75
C76
X
X
X
X
X
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Couplers for hair coloring compositions for oxidative dyeing of hair are compounds of formula (1):
wherein X is selected from halogen; R 3 is selected from the group consisting of C 1 to C 2 alkyl and hydroxyethyl; and R, R 1 and R 2 are each independently selected from C 1 to C 22 alkyl or C 1 to C 22 mono or dialkyl groups, or two of R, R 1 and R 2 together with the the nitrogen atom to which they are attached form a C 3 to C 6 cycloaliphatic or a C 3 to C 14 aromatic group, the cycloaliphatic or aromatic group optionally containing in their rings one or more hetero atoms selected from O, S and N atoms.
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TECHNICAL FIELD
The invention relates generally to the transmission of data to multiple computers in a computer network and, more particularly, to a designating the minimum-cost paths for disseminating data in a computer network.
BACKGROUND OF THE INVENTION
In the field of computer networking, many efforts have been made to determine the best way for servers within a computer network to communicate with one another. In particular, the problem of which network links to use has been a challenge. While there may be a dozen paths that communication between two computers may use, only one or two of those paths may actually be the best. In making this determination, a network engineer may have a set of parameters to follow. These parameters may include: minimizing the distance that communications need to travel, maximizing the bandwidth available for each communication, or minimizing the amount of money spent creating the links between the computers. Such parameters will hereinafter be grouped under the general category of “cost.” In other words, a network engineer tries to minimize the cost of sending messages between computers in a network. The “cost” of a network link as used herein may include, but is not limited to, one or more of the following: the time it takes for data to travel over the link, the physical length of the link, or the monetary cost of the link. Thus, if travel time is being used as a parameter, then a “cheap” link is one that is relatively fast, whereas an “expensive” link is relatively slow.
Several techniques have been developed to create minimum-cost network topologies. However, many of these techniques become unworkable when the problem of intermediate servers is introduced into a network. Intermediate servers are those servers that co-exist in a network with the servers for which communication is being optimized, but are not the intended recipients of the message. Those servers that are the intended recipients will be referred to herein as “recipient servers.”
For example, servers on computer networks may share what is known as a “multi-master” or “distributed” database, in which multiple servers share responsibility for keeping the contents of the database current. An example of such a database is the MICROSOFT ACTIVE DIRECTORY SERVICE. Copies of parts or all of a shared database may be stored on several servers. When one server makes a change to a portion of the database, that change needs to be transmitted to all of the other servers that possess copies of that portion. Transmitting database changes from one server to another is also known as “replicating” the changes. Replication among the various servers of a network takes place according to an established pattern or “replication topology.” Those servers that share the responsibility for maintaining the shared database will be referred to herein as “replicating servers.” A replicating server is one implementation of a “recipient server.”
There are many situations in which a network may have both replicating servers and intermediate servers. One such situation is when a shared database is divided into several partitions, in which a server may only exchange database updates with another server in the same partition. For example, a corporate directory may be divided into sales, development and marketing partitions, such that sales servers only replicate with other sales servers, development servers only replicate with other development servers, and marketing servers only replicate with other marketing servers. In such a network, dissimilar servers would be seen as intermediate servers with respect to one another. For example, marketing servers and development servers would be seen as intermediate servers by the sales servers, since sales data would not be replicated by the other two types of servers, but would simply be passed through. Data replicated between recipient servers may have to pass through these intermediate servers, and therefore they may need to be considered when determining a minimum-cost replication scheme.
Thus it can be seen that there is a need for a new method for designating communication paths in a computer network.
SUMMARY OF THE INVENTION
In accordance with the foregoing, a method for designating communication paths in a computer network is provided. According to the invention, communication paths are designated for the transmission of data throughout a network that has both recipient computers, which are the intended recipients of the data, and intermediary computers, which are not the intended recipients, but merely relay the data. Each intermediary computer is grouped with the “closest” recipient computer (i.e. the recipient computer with whom it is “least expensive” to communicate). Communication paths between the resulting groups are then identified. A representation of the network is then created. The representation replaces the intermediary computers with the inter-group communication paths, so that the inter-group communication paths appear to pass directly through the locations occupied by the intermediary computers. The created representation is then further processed so that the “least expensive” communication paths may be designated.
Additional features and advantages of the invention will be made apparent from the following detailed description of illustrative embodiments that proceeds with reference to the accompanying figures.
BRIEF DESCRIPTION OF THE DRAWINGS
While the appended claims set forth the features of the present invention with particularity, the invention, together with its objects and advantages, may be best understood from the following detailed description taken in conjunction with the accompanying drawings of which:
FIG. 1 is an example of a computer network;
FIG. 2 is an example of a computer;
FIGS. 3 a - 3 e , are an example of a procedure that may be followed in an embodiment of the invention to create a tree for a shortest path forest;
FIG. 4 shows a network having both recipient servers and intermediate servers;
FIGS. 4 a - 4 e show how an example of how to create a shortest-path forest from the network of FIG. 4 ;
FIG. 5 shows how the network of FIG. 4 may then be redrawn after a shortest-path forest has been created;
FIG. 6 illustrates a modified network representation that does not have intermediary servers;
FIGS. 7 a - 7 g show an example how a spanning tree may be created from the modified network representation of FIG. 6 ;
FIG. 8 shows the final topology of the network of FIG. 4 after a procedure is performed according to an embodiment of the invention;
FIG. 9 shows an example architecture of an embodiment of the invention;
FIG. 10 shows how communication may occur in a network having some servers that are designated as read-only and some servers that are designated as writeable; and,
FIG. 11 shows an example of how a two-tier topology may result when read-only and writeable servers are used in an embodiment of the invention.
DETAILED DESCRIPTION OF THE INVENTION
Although it is not required, the invention may be implemented by program modules that are executed by a computer. Generally, program modules include routines, objects, components, data structures and the like that perform particular tasks or implement particular abstract data types. A program may include one or more program modules. The invention may be implemented on a variety of types of computers, including personal computers (PCs), hand-held devices, multi-processor systems, microprocessor-based programmable consumer electronics, network PCs, minicomputers, mainframe computers and the like. The invention may also be employed in distributed computing environments, where tasks are performed by remote processing devices that are linked through a communications network. In a distributed computing environment, modules may be located in both local and remote memory storage devices.
An example of a networked environment in which this system may be used will now be described with reference to FIG. 1 . The example network includes several computers 100 communicating with one another over a network 102 , represented by a cloud. Network 102 may include many well-known components, such as routers, gateways, hubs, etc. and may allow the computers 100 to communicate via wired and/or wireless media.
Referring to FIG. 2 , an example of a basic configuration for a computer on which the system described herein may be implemented is shown. In its most basic configuration, the computer 100 typically includes at least one processing unit 112 and memory 114 . Depending on the exact configuration and type of the computer 100 , the memory 114 may be volatile (such as RAM), non-volatile (such as ROM or flash memory) or some combination of the two. This most basic configuration is illustrated in FIG. 2 by dashed line 106 . Additionally, the computer may also have additional features/functionality. For example, computer 100 may also include additional storage (removable and/or non-removable) including, but not limited to, magnetic or optical disks or tape. Computer storage media includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storage of information such as computer readable instructions, data structures, program modules, or other data. Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, digital versatile disk (DVD) or other optical storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium which can be used to stored the desired information and which can be accessed by the computer 100 . Any such computer storage media may be part of computer 100 .
Computer 100 may also contain communications connections that allow the device to communicate with other devices. A communication connection is an example of a communication medium. Communication media typically embodies computer readable instructions, data structures, program modules or other data in a modulated data signal such as a carrier wave or other transport mechanism and includes any information delivery media. By way of example, and not limitation, communication media includes wired media such as a wired network or direct-wired connection, and wireless media such as acoustic, RF, infrared and other wireless media. The term computer readable media as used herein includes both storage media and communication media.
Computer 100 may also have input devices such as a keyboard, mouse, pen, voice input device, touch input device, etc. Output devices such as a display 116 , speakers, a printer, etc. may also be included. All these devices are well known in the art and need not be discussed at length here.
According to an embodiment of the invention, the topology of a computer network having intermediate servers may be generated or reorganized so that each intermediate server is grouped with the recipient server with which it is cheapest to communicate. These groupings will be referred to herein as “trees,” with the collection of trees being referred to as a “shortest-path forest.” In a shortest-path forest, each tree has a replicating server as its “root,” and possibly one or more intermediate servers as its “branches.” Links between these groups or “trees” may then be identified and the paths between recipient servers through the branches and through the inter-tree links may be represented without the intermediate servers. As used herein, the terms “shortest path” “closest” and the like do not necessarily equate to physical distance, but are rather meant to be expressions of cost as defined in the Background section. In other words, two servers having a direct link between them that is relatively cheap are said to be “close.” Likewise, the “shortest path” between two servers is really the “cheapest” path in terms of bandwidth, monetary cost, speed, physical distance or whatever other criteria is being used to set up the communication topology.
In one embodiment of the invention, a shortest path forest is first generated using a procedure that is based on Dijkstra's Algorithm. According to this procedure, the replicating servers are designated as the roots. Then, each intermediate server is grouped with the root having the cheapest link to it. Referring to FIGS. 3 a - 3 e , an example of a procedure that may be followed in an embodiment of the invention to create a tree for a shortest path forest is shown. It is assumed in this example that server 150 is a recipient server, while servers 152 , 154 , 156 and 158 are intermediate servers. The costs of the links between the servers is also shown. For example, the cost of the link between server 152 and 154 is 2 units. Again, the units can signify any factor or combination of factors that need to be minimized.
According to the procedure, the server 150 is designated as the root server as shown in FIG. 3 a . Server 156 is then determined to be the intermediate server that is closest to the root server (i.e. the intermediate server to which the link is cheapest), since the link to it costs 5. The server 156 is therefore added to the shortest path tree ( FIG. 3 b ). In the following phase of the procedure, the server 158 is determined to be the next closest intermediate server (with a cost of 5+2=7). The server 158 is thus added to the tree ( FIG. 3 c ). The program continues this process as shown in FIGS. 3 d - 3 e , until all intermediate servers are grouped into the tree. The result is a shortest path tree that has server 150 as its root and servers 152 , 154 , 156 and 158 as its branches via the boldfaced links.
An example of a procedure that creates a shortest-path forest according to an embodiment of the invention will now be described. To aid in this example, a network having both recipient servers and intermediate servers is shown in FIG. 4 . The network, generally labeled 180 , maintains a directory service database that is shared by servers A-J. These servers replicate changes to the database to one another. The database is divided into several partitions, including a “sales partition.” The sales partition is maintained by sales servers A-E while the other partitions are maintained by intermediate servers F-J. The cost of each link is also shown. To create a shortest path forest from the network 180 , the recipient servers A-E are designated to be roots, as shown in FIG. 4 a . Then, the intermediate server that is closest to the roots is identified. In this example, intermediate servers I and J are each 10 units away from the roots (servers C and E). Thus, server I is grouped with server C, and server J is grouped with server E ( FIGS. 4 b and 4 c ). Since servers I and J have already been grouped with respective roots, they should not be grouped with any other roots. The procedure then continues as shown in FIGS. 4 d and 4 e , in which the next closest intermediate servers are identified and grouped with the root servers to which they are closest. Thus, server G is grouped with server B, while server F is grouped with server D. Thus far, four trees have been created, having servers B, C, D and E as their roots. Since all of the intermediate servers having direct links to root servers have been accounted for, the procedure will move on to the next layer of intermediate servers. In this example, there is only one intermediate server remaining—server H. The root server closest to server H is server E, with a total distance (i.e. cost) of 20 units. This includes the distance of 10 from server H to server J plus the distance of 10 from server J to server E. Thus, server H is added on as a “branch” to the tree whose root is server E.
Once all of the servers of the network 180 have been grouped into trees, the shortest-path forest can be considered complete. The network 180 may then be redrawn so that the roots of the trees are at the bottom, as shown in FIG. 5 . As shown, the trees do not touch one another. Based on the shortest-path forest representation of the network, the intermediate servers G-J can be eliminated, leaving only the sales servers A-F. In an embodiment of the invention, this may be accomplished by the following: for each link in the shortest-path forest that connects two trees, calculating the total cost of the path that connects the roots of the two trees over those links—including any intervening branches, and creating a new replication topology map that shows the link as passing directly from one root to another, without any intervening servers, and having the calculated total cost. This is illustrated in the modified network representation 190 of FIG. 6 .
Now, the most efficient network links for the recipient servers of the network 180 to use for communication can be determined. Typically, determining which network links to use for sending data between recipient servers involves three goals. First, all recipient servers should be connected in the communication topology. Second, redundant communication paths should be avoided. Finally, the total cost of the network links used in the topology should be minimized. One way to fulfill these three goals is to create a so-called “minimum-cost spanning tree”—referred to herein as a “spanning tree.” Several methods exist for creating a spanning tree, one of which involves the use of Kruskal's algorithm, developed by Joseph Kruskal of BELL LABS. This method involves:
(1) Finding the cheapest link that has not yet been considered; (2) If the link is not redundant, adding it to the tree; (3) If there are no more edges, stopping the procedure; and, (4) If there are more edges, repeating steps (1)-(3).
Referring to FIGS. 7 a - 7 g , an example how a spanning tree may be created from the modified network representation 190 will now be described. First, the cheapest link is identified. In this case, the cheapest link is the one between servers E and C. Since the link is not redundant, it is added to the spanning tree ( FIG. 7 a ). The next cheapest link is the one between servers C and D. Again, since the link is not redundant, it is added to the spanning tree ( FIG. 7 b ). The process then moves to the next cheapest link, which is the 45-unit link between servers E and D. This link is redundant, since there is already a path between servers E and D in the spanning tree—namely, the path that passes through server C ( FIG. 7 c ). The process then continues, and the link between servers B and E is added ( FIG. 7 d ), the 50-unit link between servers E and D is ignored ( FIG. 7 e ), the link between servers B and A is added ( FIG. 7 f ), and the remaining links that are not already in the spanning tree are ignored ( FIG. 7 g ). At this point, the generation of the communication topology for the network 180 ( FIG. 4 ) is complete. The final version of the topology is illustrated in FIG. 8 , with the intermediate servers being shown in their respective positions. The total cost of the communication path (in bold) is 181 units.
In the previous examples, it has been assumed that there is full connectivity between the various servers of the network 180 . In reality certain links may not have full connectivity with one another, even if they have endpoints at the same server. For example, a bridge may be required to get data from one link to another. When bridges are present, the above-described procedure may have to be modified so that a shortest-path forest is generated for each bridge prior to the creation of a minimum-cost spanning tree. Also, some links may use incompatible transport protocols, or be available only at certain times. In such cases, the above-described procedure may also have to be modified so that those servers that share a transport protocol or have compatible schedules are treated separately for the purpose of generating a shortest-path forest.
In an embodiment of the invention, the network 180 ( FIG. 4 ) is implemented as a shared database network in which servers A-E are replicating servers and servers F-J are intermediate servers. For example, the network 180 may be a directory service network that is partitioned between sales, marketing and development. The servers A-E may be sales servers, and have the need to replicate sales directory changes to one another, while the servers F-J may be either marketing or development servers, which do not change the sales directory and do not need to receive sales directory changes. In this embodiment, the goal of the shortest-path forest and spanning tree procedures described in conjunction with FIG. 4 , FIGS. 4 a-j , FIG. 5 , FIG. 6 , FIGS. 7 a - 7 g and FIG. 8 is to establish the most optimal replication paths between replicating servers A-E.
There are many ways to implement the present invention in software. In one implementation, illustrated in FIG. 9 , a software module 182 executes on each of the recipient servers A-E, maintains a communication topology map, and is responsible for communicating with the other servers as necessary. For example, if the network 180 is a shared database network, then the software module 182 on each recipient (i.e. replicating) server A-E would be responsible for maintaining a replication topology map and for ensuring that all database updates that occurred locally are replicated to other replicating servers along the designated replication paths.
The invention described herein may be used to establish communication paths between computers located at the same site and/or between groups of computers located at different sites. Referring to FIG. 4 , for example, the servers A-E may represent five satellite offices located in five different cities. Each satellite office may have dozens of computers, but with only one server in the office designated to communicate outside of the site. There may be one communication topology map for communication within a site and another map for communication between sites.
When implemented on a shared database network, it may be desirable to modify certain aspects of the invention in order to account for read-only servers. For example, in a directory service database, some servers may hold ‘writeable’ copies of a partition, while others may hold ‘read-only’ copies. In such a scenario, database replication may be set up so that changes are only replicated from writeable servers. In other words, replication between two writeable servers occurs in both directions, but if a writeable server and a read-only server are involved, then replication only occurs from the writeable server to the read-only server, and not vice versa.
According to an embodiment of the invention, additional parameters may be included in the process of designating communication links in order to account for the presence of read-only servers. These parameters include, but are not limited to:
(1) All writeable servers should be linked to one another without any intervening read-only servers;
(2) Read-only servers should be connected to the writeable servers so that they can replicate in any changed data; and,
(3) Read-only servers should not replicate in from other read-only servers, since the other read-only servers cannot possibly have any changes. However, read-only servers may replicate from other read-only servers if required by the communication links of the network. An example would be where a read-only server was connected to the rest of the network solely by a link to another read-only server that was, itself, well connected to the rest of the network.
To illustrate an implementation of these parameters, a simple network, generally labeled 200 , is shown in FIG. 10 , with the resulting spanning tree next to it. Even though the link between servers A and B is the most expensive, parameter number one indicates that it should be used for replication, since servers A and B are both writeable. Additionally, since server D is read-only, any changes to it must have come from server C. Thus, server C does not have to replicate from server D.
As a result, when there are both writeable and read-only servers in a shared-database network, and this embodiment of the invention is used, the replication topology ends up being a ‘two-tiered’ tree, in which the top tier includes all of the writeable servers linked in a bi-directional minimum spanning tree, and the bottom tier includes the read-only servers. The bottom tier may include several trees appended to the tier, in which replication occurs in a downward direction. In this example, “downward” means “away from the writeable servers.” An example of a two-tier tree is shown in FIG. 11 . As it can be seen, some read-only servers are closer to the writeable servers than other read-only servers, but the closer read-only servers don't need to replicate in from the farther ones.
It can thus be seen that a new a useful method for designating communication paths in a network has been provided. In view of the many possible embodiments to which the principles of this invention may be applied, it should be recognized that the embodiments described herein with respect to the drawing figures is meant to be illustrative only and should not be taken as limiting the scope of invention. For example, those of skill in the art will recognize that the elements of the illustrated embodiments shown in software may be implemented in hardware and vice versa or that the illustrated embodiments can be modified in arrangement and detail without departing from the spirit of the invention. Therefore, the invention as described herein contemplates all such embodiments as may come within the scope of the following claims and equivalents thereof.
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A method for designating communication paths in a computer network is provided, in which communication paths are designated for the transmission of data throughout a network. The network may have both recipient computers, which are the intended recipients of the data, and intermediary computers, which are not the intended recipients, but merely relay the data. Each intermediary computer is grouped with the “closest” recipient computer (i.e. the recipient computer with whom it is “least expensive” to communicate). Communication paths between the resulting groups are then identified. A representation of the network is then created. The representation replaces the intermediary computers with the inter-group communication paths, so that the inter-group communication paths appear to pass directly through the locations occupied by the intermediary computers. The created representation is then further processed so that the “least expensive” communication paths may be designated.
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FIELD OF THE INVENTION
This invention pertains to binders and plasticizers for pyrotechnic materials and, more specifically, to energetic binders and plasticizers for solid propellant systems.
DESCRIPTION OF RELATED ART
Solid propellants may be formulated from an oxidizer and fuel together with suitable binders and plasticizers to impart physical integrity. Most highly energetic systems utilize binders and plasticizers containing energetic moieties such as nitro (--NO 2 ), or other groups. In addition to the nitro-containing binders and plasticizers, azido-substituted binders and plasticizers are also utilized because of their ability to impart substantial energy to propellants.
One known azido binder is a hydroxy-terminated aliphatic polyether having directly pendant azidoalkyl groups such as disclosed and claimed in U.S. Pat. No. 4,268,450. The present invention, while contemplating the production of a polyether having a general structural formula such as described in U.S. Pat. No. 4,268,450, utilizes select reactants in preparing glycidyl azide polymers at a substantially improved rate of production.
SUMMARY OF THE INVENTION
Accordingly, there is provided by the present invention a family of compounds having the general formula ##STR1## wherein x is an integer having a value of from about 10 to about 60, y is an integer having a value from 1 to about 4, and R is the hydroxy-free residue of a mono-hydric alcohol, diol, triol, or polyol initiator. The novel method for production is hereinafter set out in greater detail.
OBJECTS OF THE INVENTION
It is an object of the present invention to provide a new method of glycidyl azide polymer production.
It is yet another object of the invention to provide an improved method of polymer production wherein the rate of reaction of the polyepichlorohydrin precursor with an azide ion in a solvent is enhanced utilizing select catalysts.
These and other objects of the present invention will be apparent from the following description of the preferred embodiment.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In accordance with the present invention there is provided a hydroxy-terminated aliphatic polyether having pendant azidoalkyl groups. These hydroxy-terminated aliphatic polyethers synthesized in accordance with the present invention have the following generic or general structural formula ##STR2## wherein x is an integer having a value of from about 10 to about 60, R is the hydroxy-free residue of a mono-hydric alcohol, diol, triol, or polyol initiator, and y is an integer having a value of 1 to about 4 indicative of the number of hydroxy groups present in the initiator. For example and without limitation, R may be CH 2 CH 2 , CH 2 CHCH 2 and C(CH 2 ) 4 from HOCH 2 CH 2 OH, HOCH 2 CHOHCH 2 OH and C(CH 2 OH) 4 , respectively, which are representative of initiator residues which provide multifunctional azidoalkyl polymeric ethers.
The glycidyl azide polymer (GAP) may be produced in a solution of dimethylsulfoxide (DMSO) from the azide ion, and polyepichlorohydrin (PECH), which is prepared by polymerization of epichlorohydrin (ECH) using ethylene glycol or other polyol initiator and boron trifluoride catalyst.
A representative hydroxy-terminated aliphatic polyether, for example, a glycidyl azide diol, is prepared from a diol polyepichlorohydrin (PECH) in accordance with the present invention as follows: ##STR3## where x is an integer having a value of from about 10 to 60.
GAP triol, GAP tetraol, and GAP polyols would be prepared in analogous manner using triol, tetraol and polyol initiators in the epichlorohydrin polymerization step.
The rate of synthesis of said glycidyl azide polymers may be enhanced by utilizing a heretofore unknown catalytic interaction to enhance the solubility of the azide in DMSO. The azide reacts at a more rapid rate with the polyepichlorohydrin due to the presence of the catalyst to yield the desired polymer. The catalysts useful for increasing the rate of reaction of PECH and NaN 3 are salts selected from the chlorides and bromides of quaternary ammonium and lithium cations. The catalysts or reactants preferred for the present substitution reaction include methyltrioctylammonium chloride, dodecyltrimethylammonium chloride, lithium chloride, and lithium bromide. It has been found that these catalytic agents undergo metathesis with sodium azide to produce an azide which is more soluble than NaN 3 in the DMSO reaction mixture. The consequence of the higher concentration of azide ion so produced is to increase the reaction rate.
Solvents other than DMSO can be used for the reaction medium provided that they are good solvents for both PECH and azide ion. For example, solvents such as dimethylformamide (DMF), dimethylacetamide (DMAC), ethylene glycol, and hexamethylphosphorotriamide (HMPTA) have been used and the rates of reaction for conversion of PECH to GAP in a given solvent are increased in the presence of the said catalysts.
By way of example and not limitation, the improved synthesis according to the present invention may best be understood by the following examles.
EXAMPLE 1
Reaction Using Methyltrioctylammonium Chloride
To a stirred slurry of 37.25 g (0.573 mol) NaN 3 in 25 g DMSO was added 7.5 g (0.0186 mol) methyltrioctylammonium chloride catalyst and the mixture was heated to 100° C. A separate solution of 50 g (0.546 equivalents) PECH diol in 25 g DMSO was also heated to 100° C. prior to its rapid addition to the NaN 3 /catalyst mixture. The resulting reaction mixture slurry was maintained at 100° C. and periodically 5 ml aliquots were withdrawn to determine the extent of reaction. The aliquots were washed sequentially with 4×40 ml H 2 O and 3×4 ml (CH 3 ) 2 CHOH and then transferred with the aid of 5 ml tetrahydrofuran (THF) to a rotary vacuum evaporator where all volatile solvents were removed. From the infrared spectrum of each of the aliquots the fraction of PECH remaining was determined (from the ratio of the intensities of the C--Cl/C--H bands at 2875 cm -1 and 747 cm -1 , respectively) by comparison with a calibration curve obtained from known mixtures of the same PECH diol and the GAP prepared from it. A plot of the logorithm of the ratio of PECH concentration over initial PECH concentration as a function of reaction time yields a straight line the slope of which is the rate constant for the reaction (See Table 1). Because of the exothermic nature of the substitution reaction, the procedure can be modified slightly to permit facile management of the heat released. The modification consists of adding the PECH/DMSO mixture more gradually to the NaN 3 /catalyst/DMSO mixture such that the reaction temperature is maintained at ±5° C. of the reaction temperature of about 100° C.
EXAMPLE 2
Lithium Chloride
The experimental procedure and the quantities of reactants used were identical to those in Example 1 except that the catalyst LiCl (0.80 g, 0.0189 mol) was substituted for the methyltrioctylammonium chloride. The reaction rate constant obtained is shown in Table 1.
As shown in Table 1 below, the effect of the NaN 3 /catalyst mol ratio on the reaction rate is indicated.
TABLE 1______________________________________Psuedo First Order Rate Constants at 100° C.Catalyst NaN.sub.3 /Catalyst K.sup.-hr______________________________________Control (no catalyst) ∞ 0.659Methyltrioctylammonium 30.8 1.178chlorideLithium chloride 30.3 0.928Lithium chloride 10.0 1.587______________________________________
From Table 1, it is noted that the reaction rate is substantially accelerated in the nucelophilic substitution reaction wherein the presence of methyltrioctylammonium chloride (78.8 percent) or lithium chloride (40.8 percent) at a N 3 - /additive mole ratio of approximately 30. The substitution reaction is further accelerated (increase of 141 percent) with lithium chloride when the N 3 - /additive ratio is decreased to about 10.
Obviously, numerous variations and modifications may be made without departing from the present invention. Accordingly, it should be clearly understood that the form of the present invention described above is illustrative only and is not intended to limit the scope of this present invention.
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A method of producing a hydroxy-terminated aliphatic polyether utilizing a specific catalytic interaction to enhance the solubility and resulting reactivity of an azide moiety.
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This is a continuation of application Ser. No. 316,714, filed on Feb. 28, 1989, now abandoned, which is a continuation of application Ser. No. 122,986, filed on Nov. 19, 1987, now abandoned.
TECHNICAL FIELD
The present invention is related to antidandruff shampoos containing selenium sulfide which shampoos achieve dispersion of the selenium sulfide particles through the use of low levels of hydroxypropyl methyl cellulose.
BACKGROUD OF THE INVENTION
Lotion shampoos are widely accepted due to their ease of use, including spreading the shampoo through the hair. However, when particulate, small size active ingredients are used in lotion shampoos, dispersion of those ingredients such as selenium sulfide presents a variety of problems.
The prior art discloses antidandruff shampoos containing components designed to suspend particulate matter. Japanese Application with Open for Public Inspection No. 60,810, May 19, 1977 (Lion Fat & Oil), discloses shampoos containing 5% to 50% of an anionic surfactant, 1% to 10% of a fatty acid diethanol amide, 0.1% to 10% of an insoluble fine powder and 1% to 10% of an ethylene glycol ester. U.S. Pat. No. 4,470,982, to Winkler discloses similar compositions containing from 11% to 20% of an anionic surfactant, from 4% to 6% of a suspending agent, from 2% to 4% of an amide, a particulate antidandruff agent and water. British Patent 1,051,268, Dec. 14, 1966 to Colgate-Palmolive Company discloses selenium sulfide shampoos containing suspending agents.
While these references disclose suspending antidandruff actives, they do not provide satisfactory answers to the problems associated with dispersing particulate antidandruff agents.
It has been surprisingly found by the present inventors that certain selenium sulfide compositions can utilize low levels of nonionic polymeric materials to disperse the selenium sulfide particles.
It is an object of the present invention, therefore, to provide stable selenium sulfide lotion shampoos.
It is a further object of the present invention to provide selenium sulfide lotion shampoos utilizing low levels of nonionic polymeric dispersing agents.
It is a still further object of the present invention to provide methods of shampooing hair with improved selenium sulfide compositions.
These and other objects will become readily apparent from the detailed description which follows.
Unless otherwise indicated, all percentages and ratios herein are by weight. Additionally, all measurements are made at 25° C. in the composition or on the pure material unless otherwise specified.
SUMMARY OF THE INVENTION
The present invention relates to shampoo compositions comprising from about 10% to about 30% of a synthetic surfactant, from about 0.001% to about 0.100% of a nonionic polymeric material, from about 0.1% to about 5.0% of particulate selenium sulfide having an average particle size of less than 25 μm and water. These as well as optional components are described in detail below.
DETAILED DESCRIPTION
The essential components of the present invention as well as optional components are given in the following paragraphs.
Surfactant
An essential component of the present compositions is a surfactant. The surfactant, which may be selected from any of a wide variety of synthetic anionic, amphoteric, zwitterionic and nonionic surfactants, is present at a level of from about 10% to about 30%, preferably from about 15% to about 22%, most preferably from about 18% to about 20%.
Synthetic anionic surfactants can be exemplified by the alkali metal salts of organic sulfuric reaction products having in their molecular structure an alkyl radical containing from 8-22 carbon atoms and a sulfonic acid or sulfuric acid ester radical (included in the term alkyl is the alkyl portion of higher acyl radicals). Preferred are the sodium, ammonium, potassium or triethanolamine alkyl sulfates, especially those obtained by sulfating the higher alcohols (C 8 -C 18 carbon atoms), sodium coconut oil fatty acid monoglyceride sulfates and sulfonates; sodium or potassium salts of sulfuric acid esters of the reaction product of 1 mole of a higher fatty alcohol (e.g., tallow or coconut oil alcohols) and 1 to 12 moles of ethylene oxide; sodium or potassium salts of alkyl phenol ethylene oxide ether sulfate with 1 to 10 units of ethylene oxide per molecule and in which the alkyl radicals contain from 8 to 12 carbon atoms, sodium alkyl glyceryl ether sulfonates; the reaction product of fatty acids having from 10 to 22 carbon atoms esterified with isethionic acid and neutralized with sodium hydroxide; water soluble salts of condensation products of fatty acids with sarcosine; and other known in the art.
Zwitterionic surfactants can be exemplified by those which can be broadly described as derivatives of aliphatic quaternary ammonium, phosphonium, and sulfonium compounds, in which the aliphatic radicals can be straight chain or branched, and wherein one of the aliphatic substituents contains from about 8 to 18 carbon atoms and one contains an anionic water-solubilizing group, e.g., carboxy, sulfonate, sulfate, phosphate, or phosphonate. A general formula for these compounds is: ##STR1## wherein R 2 contains an alkyl, alkenyl, or hydroxy alkyl radical of from about 8 to about 18 carbon atoms, from 0 to about 10 ethylene oxide moieties and from 0 to 1 glyceryl moiety; Y is selected from the group consisting of nitrogen, phosphorus, and sulfur atoms; R 3 is an alkyl or monohydroxyalkyl group containing 1 to about 3 carbon atoms; X is 1 when Y is a sulfur atom and 2 when Y is a nitrogen or phosphorus atom; R 4 is an alkylene or hydroxyalkylene of from 1 to about 4 carbon atoms and Z is a radical selected from the group consisting of carboxylate, sulfonate, sulfate, phosphonate, and phosphate groups.
Examples include:
4-[N,N-di(2-hydroxyethyl)-N-octadecylammonio]-butane-1-carboxylate;
5-[S-3-hydroxypropyl-S-hexadecylsulfonio]-3-hydroxypentane-1-sulfate;
3-[P,P-diethyl-P-3,6,9-trioxatetradexocylphosphonio]-2-hydroxypropane-1-phosphate;
3-[N,N-dipropyl-N-3-dodecoxy-2-hydroxypropylammonio]-propane-1-phosphonate;
3-(N,N-dimethyl-N-hexadecylammonio)propane-1-sulfonate;
3-(N,N-dimethyl-N-hexadecylammonio)-2-hydroxypropane-1-sulfonate;
4-[N,N-di(2-hydroxyethyl)-N-(2-hydroxydodecyl)ammonio]-butane-1-carboxylate;
3-[S-ethyl-S-(3-dodecoxy-2-hydroxypropyl)sulfonio]-propane-1-phosphate;
3-[P,P-dimethyl-P-dodecylphosphonio]-propane-1-phosphonate; and
5-[N,N-di(3-hydroxypropyl)-N-hexadecylammonio]-2-hydroxypentane-1-sulfate.
Other zwitterionics such as betaines are also useful in the present invention. Examples of betaines useful herein include the high alkyl betaines such as coco dimethyl carboxymethyl betaine, lauryl dimethyl carboxymethyl betaine, lauryl dimethyl alpha-carboxy-ethyl betaine, cetyl dimethyl carboxymethyl betaine, lauryl bis-(2-hydroxy-ethyl) carboxy methyl betaine, stearyl bis-(2-hydroxy-propyl) carboxymethyl betaine, oleyl dimethyl gamma-carboxypropyl betaine, lauryl bis-(2-hydroxypropyl) alpha-carboxyethyl betaine, etc. The sulfobetaines may be represented by coco dimethyl sulfopropyl betaine, stearyl dimethyl sulfopropyl betaine, lauryl dimethyl sulfoethyl betaine, lauryl bis-(2-hydroxy-ethyl) sulfopropyl betaine and the like; amido betaines and amidosulfobetaines, wherein the RCONH(CH 2 ) 3 radical is attached to the nitrogen atom of the betaine are also useful in this invention.
Examples of amphoteric surfactants which can be used in the compositions of the present invention are those which can be broadly described as derivatives of aliphatic secondary and tertiary amines in which the aliphatic radical can be straight chain or branched and wherein one of the aliphatic substituents contains from about 8 to about 18 carbon atoms and one contains an anionic water solubilizing group, e.g., carboxy, sulfonate, sulfate, phosphate, or phosphonate. Examples of compounds falling within this definition are sodium 3-dodecyl-aminopropionate, sodium 3-dodecylaminopropane sulfonate, N-alkyltaurines such as the one prepared by reacting dodecylamine with sodium isethionate according to the teaching of U.S. Pat. No. 2,658,072, N-higher alkyl aspartic acids such as those produced according to the teaching of U.S. Pat. No. 2,438,091, and the products sold under the trade name "Miranol" and described in U.S. Pat. No. 2,528,378.
Nonionic surfactants, which are preferably used in combination with an anionic, amphoteric or zwitterionic surfactant, can be broadly defined as compounds produced by the condensation of alkylene oxide groups (hydrophilic in nature) with an organic hydrophobic compound, which may be aliphatic or alkyl aromatic in nature. Examples of preferred classes of nonionic surfactants are:
1. The polyethylene oxide condensates of alkyl phenols, e.g., the condensation products of alkyl phenols having an alkyl group containing from about 6 to 12 carbon atoms in either a straight chain or branched chain configuration, with ethylene oxide, the said ethylene oxide being present in amounts equal to 10 to 60 moles of ethylene oxide per mole of alkyl phenol. The alkyl substituent in such compounds may be derived from polymerized propylene, diisobutylene, octane, or nonane, for example.
2. Those derived from the condensation of ethylene oxide with the product resulting from the reaction of propylene oxide and ethylene diamine products which may be varied in composition depending upon the balance between the hydrophobic and hydrophilic elements which is desired. For example, compounds containing from about 40% to about 80% polyoxyethylene by weight and having a molecular weight of from about 5,000 to about 11,000 resulting from the reaction of ethylene oxide groups with a hydrophobic base constituted of the reaction product of ethylene diamine and excess propylene oxide, said base having a molecular weight of the order of 2,500 to 3,000, are satisfactory.
3. The condensation product of aliphatic alcohols having from 8 to 18 carbon atoms, in either straight chain or branched chain configuration, with ethylene oxide, e.g., a coconut alcohol ethylene oxide condensate having from 10 to 30 moles of ethylene oxide per mole of coconut alcohol, the coconut alcohol fraction having from 10 to 14 carbon atoms.
4. Long chain tertiary amine oxides corresponding to the following general formula:
R.sub.1 R.sub.2 R.sub.3 N→O
wherein R 1 contains an alkyl, alkenyl or monohydroxy alkyl radical of from about 8 to about 18 carbon atoms, from 0 to about 10 ethylene oxide moieties, and from 0 to 1 glyceryl moiety, and R 2 and R 3 contain from 1 to about 3 carbon atoms and from 0 to about 1 hydroxy group, e.g., methyl, ethyl, propyl, hydroxy ethyl, or hydroxy propyl radicals. The arrow in the formula is a conventional representation of a semipolar bond. Examples of amine oxides suitable for use in this invention include dimethyldodecylamine oxides, oleyldi(2-hydroxyethyl) amine oxide, dimethyloctylamine oxide, diemthyl-decylamine oxide, diemthyltetradecylamine oxide, 3,6,9-trioxaheptadecyldiethylamine oxide, di(2-hydroxyethyl)-tetradecylamine oxide, 2-dode-coxyethyldimethylamine oxide, 3-dodecoxy-2-hydroxypropyldi(3-hydroxypropyl)amine oxide, dimethylhexadecylamine oxide.
5. Long chain tertiary phosphine oxides corresponding to the following general formula:
RR'R"P→O
wherein R contains an alkyl, alkenyl or monohydroxyalkyl radical ranging from 8 to 18 carbon atoms in chain length, from 0 to about 10 ethylene oxide moieties and from 0 to 1 glyceryl moiety and R' and R" are each alkyl or monohydroxyalkyl groups containing from 1 to 3 carbon atoms. The arrow in the formula is a conventional representation of a semipolar bond. Examples of suitable phosphine oxides are: dodecyldimethylphosphine oxide, tetradecyldimethylphosphine oxide, tetradecylmethylethylphosphine oxide, 3,6,9,-trioxaoctadecyldimethylphosphine oxide, cetyldimethylphosphine oxide, 3-dodecoxy-2-hydroxypropyldi(2-hydroxyethyl) phosphine oxide, stearyldimethylphosphine oxide, cetylethylpropylphosphine oxide, oleyldiethylphosphine oxide, dodecyldiethylphosphine oxide, tetradecyldiethylphosphine oxide, dodecyldipropylphosphine oxide, dodecyldi(hydroxymethyl)phosphine oxide, dodecyldi(2-hydroxyethyl)phosphine oxide, tetradecylmethyl-2-hydroxypropylphosphine oxide, oleyldimethylphosphine oxide, 2-hydroxydodecyldimethylphosphine oxide.
6. Long chain dialkyl sulfoxides containing one short chain alkyl or hydroxy alkyl radical of 1 to about 3 carbon atoms (usually methyl) and one long hydrophobic chain which contain alkyl, alkenyl, hydroxy alkyl, or keto alkyl radicals containing from about 8 to about 20 carbon atoms, from 0 to about 10 ethylene oxide moieties and from 0 to 1 glyceryl moiety. Examples include: octadecyl methyl sulfoxide, 2-ketotridecyl methyl sulfoxide, 3,6,9,-trioxaoctadecyl 2-hydroxyethyl sulfoxide, dodecyl methyl sulfoxide, oleyl 3-hydroxypropyl sulfoxide, tetradecyl methyl sulfoxide, 3-methoxytridecyl methyl sulfoxide, 3-hydroxytridecyl methyl sulfoxide, 3-hydroxy-4-dodecoxybutyl methyl sulfoxide.
Many additional nonsoap surfactants are described in McCUTCHEON'S, DETERGENTS AND EMULSIFIERS, 1986 ANNUAL, published by Allured Publishing Corporation, which is incorporated herein by reference.
The above-mentioned surfactants can be used alone or in combination in the shampoo compositions of the present invention. The anionic surfactants, particularly the alkyl sulfates, the ethoxylated alkyl sulfates and mixtures thereof are preferred for use herein as well as the isethionates.
Nonionic Polymeric Material
Another essential component of the present compositions is a nonionic polymer material which is used at a low level to aid in keeping the particles of selenium sulfide dispersed. The material can be any of a large variety of types including cellulosic materials such as hydroxypropyl methyl cellulose, carboxymethyl cellulose, hydroxyethyl cellulose and sodium carboxymethyl cellulose. Other materials include alginates, polyacrylic acids, polyethylene glycol and starches among many others. The nonionic polymers are discussed in detail in Industrial Gums, Edited by Roy L. Whistler, Academic Press, Inc., (1973) and Handbook of Water-Soluble Gums and Resins, Edited by Robert L. Davidson, McGraw-Hill, Inc. (1980). Both of these references in their entirety are incorporated herein by reference.
The nonionic polymer is used at a level of from about 0.001% to about 0.100%, preferably from about 0.002% to about 0.05%. Hydroxypropyl methyl cellulose is the preferred polymer.
Selenium Sulfide
Selenium sulfide is a staple item of commerce. Selenium sulfide is generally regarded as a compound having one mole of selenium and two moles of sulfur. However, it may take the form of a cyclic structure, Se x S y , wherein x+y=8.
Selenium sulfide as provided by suppliers can be used in the present compositions provided the particle size of the selenium sulfide particles, on an average, is less than about 25μ, preferably less than about 15. These measurements are made using a forward laser light scattering device (e.g., a Malvern 3600 instrument).
Selenium sulfide is present in the compositions of this invention at a level of from about 0.1% to about 5.0%, preferably from about 0.6% to about 2.5%.
Water
Water is the last essential component of the present invention and forms the remainder of the composition. It is generally present at a level of from about 20% to about 95%, preferably from about 60% to about 85%.
Optional Components
A preferred optional component is a suspending agent. The suspending agent useful in the present compositions can, for example, be any of several long chain acyl derivative materials or mixtures of such materials. Included are ethylene glycol esters of fatty acids having from about 16 to about 22 carbon atoms. Preferred are the ethylene glycol stearates, both mono and distearate, but particularly the distearate containing less than about 7% of the mono stearate. Still other suspending agents found useful are alkanol amides of fatty acids, having from about 16 to about 22 carbon atoms, preferably about 16 to 18 carbon atoms. Preferred alkanol amides are stearic monoethanolamide, stearic diethanolamide and stearic monoisopropanolamide. Still other long chain acyl derivatives include long chain esters of long chain fatty acids (e.g., stearyl stearate, cetyl palmitate, etc.); glyceryl esters (e.g., glyceryl distearate) and long chain esters of long chain alkanol amides (e.g., stearamide DEA distearate, stearamide MEA stearate).
Still other suitable suspending agents are alkyl (C 16-22 ) dimethyl amine oxides such as stearyl dimethyl amide oxide. If the compositions contain an amine oxide or a long chain acyl derivative as a surfactant the suspending function could also be provided and additional suspending agent may not be needed if the level of those materials are at least the minimum level given below.
Another suspending agent is veegum (magnesium, aluminum silicate). Xanthan gum is another agent used to suspend the selenium sulfide in the present compositions. This biosynthetic gum material is commercially available and is a heteropolysaccharide with a molecular weight of greater than 1 million. It is believed to contain D-glucose, D-mannose and D-glucuronate in the molar ratio of 2.8:2.0:2.0. The polysaccharide is partially acetylated with 4.7% acetyl. This information and other is found in Whistler, Roy L. Editor Industrial Gums--Polysaccharides and Their Derivatives New York: Academic Press, 1973. Kelco, a Division of Merck & Co., Inc. offers xanthan gum as Keltrol®.
The suspending agent is present at a level of from about 0.10% to about 5.0%, preferably from about 0.5% to about 3.0%. The suspending agent serves to assist in suspending the selenium sulfide and may give pearlescence to the product. Mixtures of suspending agents are also suitable for use in the compositions of this invention.
Another preferred optional component for use in the present compositions is an amide. The amide used in the present compositions can be any of the alkanolamides of fatty acids known for use in shampoos. These are generally mono- and diethanolamides of fatty acids having from about 8 to about 14 carbon atoms. Preferred are coconut monoethanolamide, lauric diethanolamide and mixtures thereof.
The amide is present at a level of from about 1% to about 10%.
Another suitable optional component useful in the present compositions is a nonvolatile silicone fluid.
The nonvolatile silicone fluid may be either a polyalkyl siloxane, a polyaryl siloxane, a polyalkylaryl siloxane or a polyether siloxane copolymer and is present at a level of from about 0.1% to about 10.00%, preferably from about 0.5% to about 5.0%. Mixtures of these fluids may also be used and are preferred in certain executions. The dispersed silicone particles should also be insoluble in the shampoo matrix. This is the meaning of "insoluble" as used hereinbefore and hereinafter.
The essentially nonvolatile polyalkyl siloxane fluids that may be used include, for example, polydimethyl siloxanes with viscosities ranging from about 5 to 600,000 centistokes at 25° C. These siloxanes are available, for example, from the General Electric Company as the Viscasil series and from Dow Corning as the Dow Corning 200 series. The viscosity can be measured by means of a glass capillary viscometer as set forth in Dow Corning Corporate Test Method CTM0004, Jul. 20, 1970. Preferably the viscosity range from about 350 centistokes to about 100,000 centistokes.
The essentially nonvolatile polyalkylaryl siloxane fluids that may be used include, for example, polymethylphenylsiloxanes having viscosities of about 15 to 30,000 centistokes at 25° C. These siloxanes are available, for example, from the General Electric Company as SF 1075 methyl phenyl fluoride or from Dow Corning as 556 Cosmetic Grade Fluid.
The essentially nonvolatile polyether siloxane copolymer that may be used is, for example, a polypropylene oxide modified dimethylpolysiloxane (e.g., Dow Corning DC-1248) although ethylene oxide or mixtures of ethylene oxide and propylene oxide may also be used.
References disclosing suitable silicone fluids include the previously mentioned U.S. Pat. No. 2,826,551 to Geen; U.S. Pat. No. 3,964,5000, Jun. 22, 1976 to Drakoff; U.S. Pat. No. 4,364,837 to Pader and British Patent 849,433 to Woolston. All of these patents are incorporated herein by reference. Also incorporated herein by reference is Silicon Compounds distributed by Petrarch Systems, Inc., 1984. This reference provides a very good listing of suitable silicone materials.
Another silicone material found especially useful in the present compositions to provide good dry combing is a silicone gum. Silicone gums described by Petrarch and others including U.S. Pat. No. 4,152,416, May 1, 1979 to Spitzer, et al. and Noll, Walter, Chemistry and Technology of Silicones, New York: Academic Press 1968. Also describing silicone gums are General Electric Silicone Rubber Product Data Sheets Se 30, SE 33, SE 54 and SE 76. All of these described references are incorporated herein by reference. "Silicone gum" materials denote high moleculate weight polydiorganosiloxanes having a mass molecular weight of from about 200,000 to about 1,000,000. Specific examples include polydimethylsiloxane, (polydimethylsiloxane) (methylvinylsiloxane) copolymer, poly(dimethylsiloxane) (diphenyl) (methylvinylsiloxane) copolymer and mixtures thereof.
The shampoos herein can contain a variety of other non-essential optional components suitable for rendering such compositions more acceptable. Such conventional optional ingredients are well known to those skilled in the art, e.g., preservatives such as benzyl alcohol, methyl paraben, propyl paraben and imidazolidinyl urea; cationic surfactants such as cetyl trimethyl ammonium chloride, lauryl trimethyl ammonium chloride, tricetyl methyl ammonium chloride, stearyldimethyl benzyl ammonium chloride, and di(partially hydrogenated tallow) dimethylammonium chloride; menthol; thickeners and viscosity modifiers such as block polymers of ethylene oxide and propylene oxide such as Pluronic F88 offered by BASF Wyandotte, sodium chloride, sodium sulfate, propylene glycol, and ethyl alcohol; pH adjusting agents such as citric acid, succinic acid, phosphoric acid, sodium hydroxide, sodium carbonate, etc.; perfumes; dyes; and, sequestering agents such as disodium ethylenediamine tetraacetate. Such agents generally are used individually at a level of from about 0.01% to about 10%, preferably from about 0.5% to about 5.0% by weight of the composition.
The pH of the present compositions is generally not critical and may be obtained through the proper selection of surfactants or through the use of appropriate buffer systems to control pH such as citric acid/sodium citrate. Improved color stability is, however, achieved by maintaining the pH within the range of from about 2 to about 6, preferably from about 3 to about 5.
METHOD OF MANUFACTURE
One method for manufacturing the present composition is described below in the Examples.
INDUSTRIAL APPLICABILITY
The present compositions are used in a conventional manner for cleaning hair. From about 0.1 g to about 10 g of a composition is applied to hair that has been wetted, generally with water, worked through the hair and then rinsed out.
The following Examples further describe and demonstrate the preferred embodiments within the scope of the present invention. The Examples are given solely for the purpose of illustration and are not to be construed as limitations of the present invention as many variations thereof are possible without departing from its spirit and scope.
EXAMPLES I-III
The following compositions are representative of the present invention.
______________________________________ Weight %Component I II III______________________________________EGDS PremixWater 52.44 52.44 52.44Alkyl sulfate 28.84 28.84 28.84Alkyl xylene sulfonate 2.69 2.69 2.69Cetyl alcohol 0.57 0.57 0.57Stearyl alcohol 0.42 0.42 0.42Coconut monoethanolamide 6.87 6.87 6.87Ethylene glycol distearate 6.87 6.87 6.87(EGDS)Tricetyl methyl ammonium chloride 1.30 1.30 1.30 100.00 100.00 100.00______________________________________Silicone PremixAlkyl (ethoxy) sulfate 62.24 62.24 62.24Cetyl alcohol 5.46 5.46 5.46Dimethicone (fluid/gum) 30.30 30.30 30.30 100.00 100.00 100.00______________________________________Selenium Sulfide PremixDRO water 63.74 68.24 63.74Sodium citrate 0.95 0.95 0.95Citric acid 0.81 0.81 0.81Sodium alkyl sulfate 4.00 4.00 4.00Selenium sulfide 25.00 25.00 25.00Preservative 0.50 0.50 0.50Methocel Premix 5.00 0.50 5.00 100.00 100.00 100.00______________________________________Methocel PremixMethocel (Hydroypropyl 10.00 10.00 10.00methyl cellulose)DRO water 90.00 90.00 90.00 100.00 100.00 100.00______________________________________Main MixEGDS premix 42.88 42.88 42.107Silicone premix 3.24 3.24 3.24AE.sub.3 S 47.36 47.36 47.36Selenium sulfide premix 4.00 4.00 4.00Methocel premix -- -- 1.30DRO water 0.527 0.527 --Sodium citrate 0.71 0.71 0.71Citric acid 0.60 0.60 0.60Fragrance 0.65 0.65 0.65Preservative 0.033 0.033 0.033 100.000 100.000 100.000______________________________________
The above compositions are prepared by heating all of the premixes except for the selenium sulfide premix in separate making containers to 71° C., agitating them and cooling the compositions to 38° C. The selenium sulfide premix and the methocel premix are then mixed together and then combined with the other premixes to form the main mix.
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Disclosed are selenium sulfide lotion shampoos containing low levels of hydroxypropyl methylcellulose as an agent to keep the selenium sulfide particles dispersed.
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This is a Divisional of co-pending application Ser. No. 08/539,861, filed on Oct. 6, 1995.
BACKGROUND OF THE INVENTION
The present invention relates to an improvement in farm machinery which greatly increases its life. More specifically, the present invention provides an improved mechanism for attaching a closing wheel assembly to the remainder of a planter.
In modern day farm operations, spring planting is accomplished through use of a planter which deposits seeds in the ground in an orderly fashion so as to allow for controlled growing and harvesting of crops. One type of planter utilizes a mechanism known as a closing wheel assembly. The purpose of this closing wheel assembly is to compact the soil around the seed after it has been deposited in the ground so as to promote germination of the seed. As will be appreciated by those skilled in the art, the operation of this closing wheel assembly can drastically affect the manner in which crops grow each year. Improper operation has the potential to defeat the purpose of the closing wheel assembly altogether. In turn, this can directly affect crop production and yield.
Referring to FIG. 1, there is shown the side view of a typical closing wheel assembly 10. Closing wheel assembly 10 consists of a pair of closing wheels 12 attached to a closing wheel arm 20. Closing wheels 12 are attached on either side of closing wheel arm 20 and are typically aligned at an angle which causes the two wheels to meet at a bottom edge 14. Closing wheel arm 20 is then attached to the planter by a planter arm 16. Typically connection between closing wheel arm 20 and planter arm 16 is accomplished by a pair of attachment bolts 18 on either side of closing wheel arm 20.
The configuration of closing wheel assembly 10 allows the entire assembly to rotate about the axis of attachment bolts 18. This rotation allows bottom edge 14 of closing wheels 12 to travel up and down as the planter traverses the ground. As can be expected, this up and down motion (and likely some further jarring forces) causes wear at the connection joint between planter arm 16 and closing wheel arm 20.
Referring to FIG. 2 there is shown a perspective view of closing wheel arm 20 shown alone. Closing wheel arm 20 includes a pair of apertures 22 existing in a pair of parallel mounting or attachment structures 24. Also shown in FIG. 2 is an attachment structure 26 to which a closing wheel 12 is attached. The alignment of apertures 22 and an aperture in planter arm 16 (not shown) along with attachment bolts 18 is very critical to the proper alignment of the closing wheel assembly 10. The alignment of each of these apertures and their relationships to one another will affect the tracking characteristics of bottom edge 14 of closing wheels 12. As misalignment can be detrimental to the growth of seeds, such misalignment must be avoided.
As previously mentioned, the motion or movement of closing wheel assembly 10 in relation to the planter causes wear on and structural degradation in closing wheel arm 20. Specifically, wear is caused in attachment apertures 22 causing them to be enlarged. Typically the inner surface of apertures 22 is relatively small (approximately 1/8 to 1/16 inch). Thus, wear is inevitable. Once this occurs, a good deal of "play" is created in the closing wheel assembly causing it to track incorrectly.
At this point, the operator has a number of alternatives in order to correct this problem. A first alternative is to replace closing wheel arm 20 entirely. While this solution will suffice to make the planter operational once again, it is not an optimum solution as closing wheel arm 20 will simply wear out in some period of time. Furthermore, the replacement of closing wheel arm 20 with a new part creates a cumbersome and involved repair process which must be undertaken by the owner. This process is undesirable as it requires removal of all parts (including closing wheels 12) and reattachment to a new closing wheel arm 20.
Another alternative is to fill in the wear created in closing wheel arm 20. Again, this is a very involved and somewhat futile process as closing wheel arm 20 is likely to wear out once again within a short period of time. Other ineffective alternatives include the use of a washer or filler part which is adjusted to pick up slack in attachment aperture 22. This solution is also ineffective due to the need for constant readjustment as the planter is used.
Consequently, a need exists for a solution which will avoid the wear which takes place in attachment apertures 22 altogether.
SUMMARY OF THE INVENTION
The present invention provides an improved attachment assembly for a planter closing wheel arm which will substantially eliminate wear. The present invention provides a solution which will fix any problems wear has already created and also will create an improvement in the closing wheel arm 20 which will essentially eliminate any future wear. Furthermore, the present invention is extremely adaptable to a number of different configurations of the closing wheel arm 20 and very easy to install.
The present invention provides a grease bushing assembly which is attached to the closing wheel arm. This bushing assembly greatly increases the wear surface utilized by the closing wheel arm. Furthermore, the invention creates the opportunity to grease the wear surfaces thus greatly increasing their life.
When installed, the resulting product consists of a pair of outer bushings attached to the closing wheel arm. This attachment is typically done by welding. Situated within an aperture in the outer bushings is an inner bushing. This inner bushing is bolted to the planter so as to be rigidly affixed thereto. Motion of the closing wheel arm relative to the planter takes the form of rotation around the bushing configuration.
In order to achieve the improved bushing configuration contemplated by the present invention, a welding jig is provided to easily accommodate the improvement process. In the performance of the repair, the welding jig is attached to the closing wheel arm which will hold a pair of bushings in close contact with the closing wheel arm. Furthermore, the apertures in the outer bushings are held in a position so as to be coaxially aligned with one another and with the apertures contained in the closing wheel arm. This holding and alignment is essential to the proper installation of the necessary bushings. Furthermore, by the use of this welding jig, the easy attachment or welding of bushings to the closing wheel arm is accomplished.
It is therefore an object of the present invention to provide an improved configuration for the attachment of the closing wheel assembly to the planter. Further, it is an object to provide a repair kit which will repair and improve the aforementioned connection. This repair and improvement provides a rotational attachment mechanism which is low wearing and has long life.
It is a further object of the present invention to provide a process and tools necessary for easy repair of a planter by its owners. This easy repair is accomplished by providing proper alignment and holding tools so as to simplify any welding or connections required.
BRIEF DESCRIPTION OF THE DRAWINGS
Further objects and advantages of the present invention can be seen by reading the following detailed description in conjunction with the drawings in which:
FIG. 1 is a side view of the closing wheel assembly of the prior art;
FIG. 2 is a perspective view of the closing wheel arm of the prior art;
FIG. 3 is an exploded view of the parts making up the closing wheel arm repair kit; and
FIG. 4 is an exploded view of an improved closing wheel arm and its cooperating parts.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to FIGS. 3 and 4, there is shown exploded views of both of a welding jig 80 and associated parts used to incorporate the improvement (FIG. 3) and the final product (FIG. 4). Referring first to FIG. 4, there is shown the improved closing wheel arm attachment mechanism 32. Closing wheel arm 20 is shown without closing wheels 12 attached. It is understood by those skilled in the art that it is not necessary to remove closing wheels 12 during the repair or improvement process. However, these wheels are not shown for simplicity in describing the structure of the invention.
Attached to closing wheel arm 20 are a first outer bushing 40 and a second outer bushing 50. First outer bushing 40 and second outer bushing 50 are attached to a first attachment surface 28 and a second attachment surface 30, respectively. It will be noted that first attachment surface 28 and second attachment surface 30 are integral portions of closing wheel arm 20 and are the outer surfaces of attachment structure 24. The two attachment surfaces 28 and 30 are configured to be substantially parallel to one another. The attachment structure 24 extends from closing wheel assembly 20 in an ear-type configuration whereby these ears extend from and are clear from other portions of closing wheel arm 20. As previously stated with reference to FIG. 2, attachment structure 24 (and thus first attachment surface 28 and second attachment surface 30) contain attachment apertures 22 therein.
Both first outer bushing 40 and second outer bushing 50 are substantially cylindrical in configuration, each having a cylindrical aperture therein (first outer bushing aperture 42 and second outer bushing aperture 52, respectively). These bushings (40 and 50) are attached to closing wheel arm 20 such that the outer bushing apertures 42 and 52 are coaxially aligned with attachment apertures 22. Consequently, first outer bushing aperture 42, second outer bushing aperture 52 and attachment apertures 22 of closing wheel arm 20 are all aligned along a single alignment axis 34. This alignment allows for proper rotation and movement of closing wheel arm 20 as necessary during operation of the aforementioned planter.
First outer bushing 40 has a second aperture or grease aperture 44 included therein. Grease aperture 44 exists in the cylindrical wall of first outer bushing 40 and is configured such that the axis of the aperture is perpendicular to the aforementioned alignment axis 34. Placed within first bushing grease aperture 44 is a first grease fitting 46. This grease fitting is a well-known part which allows for the insertion of grease into bushing aperture 42 when assembled.
Similar to first outer bushing 40, second outer bushing 50 also has a grease aperture 54 therein. Again, this aperture is configured to be perpendicular to alignment axis 34. Fitted within aperture 54 is a second grease fitting 56.
Also shown in FIG. 4 are a first inner bushing 60 and a second inner bushing 70. Each of these bushings are also substantially cylindrical and further have a cylindrical aperture 62 and 72, respectively, therein. These bushings are configured to be inserted into first bushing aperture 42 and second bushing aperture 52. The dimensions are configured such that these bushing sets (e.g. first inner bushing 60 and first outer bushing 40, or, second inner bushing 70 and second outer bushing 50) fit in tight cooperation with one another. Following the insertion of first inner bushing 60 into first outer bushing aperture 42, a first attachment bolt 64 is inserted into first inner bushing aperture 62. This bolt is configured to extend through the inner bushing and attached to the frame or planter arm 16 (not shown) of the planter. Once so attached, first attachment bolt 64 and first inner bushing 60 are rigidly attached to planter arm 16. Similarly, a second attachment bolt 74 is inserted through second inner bushing aperture 72 and is also attached to a second side of planter arm 16 (again not shown). This attachment causes second inner bushing 70 and second attachment bolt 74 to be rigidly attached to planter arm 16.
In operation, inner bushings 60 and 70 are rigidly attached to the planter. However, they are placed in tight cooperation with outer bushings 40 and 50. This cooperation allows for rotational motion of closing wheel arm 20 about the alignment axis 34. As previously mentioned, first outer bushing 40 and second outer bushing 50 each contain grease fittings (46 and 56) so as to allow the insertion of grease into the outer bushing apertures (42 and 52). This insertion of grease causes the inner surface of apertures 42 and 52 to be coated with grease along with the outer surfaces of both first inner bushing 60 and second inner bushing 70. Thus, there is created a lubricated bushing assembly with a large wear surface. This combination (large surface area and lubrication) creates for a long wearing bushing assembly which will be resistant to structural degradation.
It will be recognized and understood that certain modifications may be necessary to adapt the improved attachment mechanism to different planters. For example, attachment apertures 22 may be smaller than first and second outer bushing apertures 42 and 52, thus requiring first inner bushing 50 and second inner bushing 70 to be modified. In this situation, first inner bushing 60 may have a portion thereof reduced in diameter such that the reduced portion will fit into attachment aperture 22, while the remaining portion will work in tight cooperation with the inner surface of first bushing aperture 42. Similar alterations will also be made to second inner bushing 70.
Referring back to FIG. 3, there is shown an exploded view of the repair system parts used to install the improved lubricated attachment mechanism. Welding jig 80 is utilized to properly align all of the parts during the installation of the improved bushing system. Initially welding jig 80 is attached to closing wheel arm 20 by use of an attachment bolt 82, a first nut 84 and an attachment wing nut 86. Attachment bolt 82 is inserted through a connection aperture 88 in welding jig 80 and attached thereto by first nut 84. An extending portion of first attachment bolt 82 is extended through an aperture 90 in closing wheel arm 20. Attachment wing nut 86 can then be used to secure closing wheel arm 20 to welding jig 80.
Welding jig 80 is utilized to properly align and position first outer bushing 40 and second outer bushing 50 so they can be easily attached to closing wheel arm 20. This attachment is typically done via welding the parts together. However, other attachment methods could be used. To accomplish this alignment, welding jig 80 includes an alignment structure 92 consisting of a structure containing two alignment apertures 94 axially aligned on either side of welding jig 80. Welding jig 80 is configured such that the alignment apertures 94 are coaxially aligned with closing wheel arm attachment apertures 22 when welding jig 80 is attached to closing wheel arm 20.
Following the attachment of welding jig 80 to closing wheel arm 20, a pair of alignment bushings 96 are inserted through attachment apertures 22 and into alignment apertures 94. Alignment bushings 96 are configured such that they will be seated in alignment aperture 94 and will extend beyond attachment surfaces 28 and 30 of closing wheel arm 20. Due to this configuration, first outer bushing 40 and second outer bushing 50 can thus be positioned around alignment bushings 96. Again, alignment bushings 96 are of a proper size such that they can be inserted into first bushing aperture 42 and second bushing aperture 52.
When properly positioned, first outer bushing 40 and second outer bushing 50 are positioned adjacent to first attachment surface 28 and second attachment surface 30 of closing wheel arm 20. All of these parts are then held in place by a holding bolt 98, a pair of washers 100 and 102, and a holding wing nut 104. Washers 100 and 102 are of a sufficient size to cover the edges of first outer bushing 40 and second outer bushing 50. Through the use of holding bolt 98 and holding wing nut 104, all of these parts are then sandwiched together and held in place so as to facilitate the attachment of first outer bushing 40 and second outer bushing 50 to the closing wheel arm 20. Due to the use of a single holding bolt 98, alignment bushings 96 and welding jig 80, first outer bushing 40 and second outer bushing 50 are axially aligned with the attachment apertures 22 in closing wheel arm 20. This alignment will assure proper operation of the closing wheel arm assembly and when used in a planter.
Again, it will be understood that modifications may be necessary to adapt to different closing wheel arm assemblies. As an example, alignment structure apertures 94 may have a smaller diameter and alignment bushings 96 may have a portion thereof with a reduced diameter. This reduced diameter again may be necessary to accommodate a reduced size of attachment apertures 22.
Having described the present invention in considerable detail, it is understood that certain modifications can be made to the specific detail described. We claim all modifications coming within the scope and spirit of the following claims.
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The disclosed invention is an improved closing wheel attachment mechanism which has longer wear life than that of the typical attachment mechanism. The closing wheel arm on an agricultural planter has installed thereon an improved grease bushing assembly which has increased wear surface and the capability to utilize a grease on the surface. The combination of increased wear surface and greasing will greatly increase the operational life of the planter. Also included in the invention is the process and fixturing to incorporate the improved configuration on to an existing planter closing wheel structure. Included in this attachment mechanism is a welding jig which assures proper alignment of the improved bushing assembly.
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FIELD OF THE INVENTION
The present invention generally relates to an apparatus for burrowing pest control, and more particularly to an apparatus for injecting flammable gas and oxygen into underground pest burrows for combustion and extermination of burrowing pests.
BACKGROUND OF THE INVENTION
Burrowing pests have been a problem for gardeners, ranchers, and farmers since time in immemorial. There have been many devices for the specific purpose of combating burrowing pests in their underground burrows including spring traps, jaw traps, spring spears, steel traps, poisons, and explosive devices. Eradicating burrowing pests is made more difficult because the pest burrow may be quite long with various entry points, underground chambers, and various escape routes. Poisonous gases have been utilized but this is dangerous to the operator and may involve such environmental impact as to make it impractical.
Explosive gases have also been injected into the system of burrows of burrowing animals. The use of explosive gases can be effective, but faces certain challenges. An applicator for injecting flammable gases into an underground burrow must cause the gas to penetrate deeply into the system of burrows for it to be effective. Usually, the flammable gas is a mixture of oxygen and a flammable gas and, at a certain distance from the injection point, the two gases can separate and the effectiveness of the combustion may become greatly reduced. Such a device also has to be very safe for the applicator so that there is no possibility of combustion around the applicator or of carrying the combustion into the device itself.
SUMMARY OF THE INVENTION
The present invention is a burrowing pest control device based on injecting a mixture of oxygen and a flammable gas into underground borrows. The device includes a valve assembly, a combustion assembly, an ignition assembly, an injector assembly, and a control panel assembly. The burrowing pest control device works by mixing oxygen and a flammable gas and injecting that mixture of gases into the hole of the burrowing pest, so that the mixture of gases penetrates some distance into the hole. At a selected time, the mixture of oxygen and flammable gas is ignited by the ignition assembly and the mixture combusts underground, thus eliminating the burrowing pest in the underground burrow.
The valve assembly includes a hose connection for an oxygen hose from a source of compressed oxygen. It also includes a hose connection for a hose supplying flammable gas from a flammable gas source. The flammable gas and the oxygen are connected from exterior sources to provide the burrowing pest control device with both of these gases. The valve assembly also includes an oxygen valve, which is configured to open and close a pathway for oxygen into the device of the invention. The flammable gas valve is also configured to open and close a pathway for flammable gas into the device. The functions of both of these valves can be combined into one valve, which controls the flow of both gases. The valve assembly also includes a valve controller which controls the oxygen valve and may also control the flammable gas valve. The oxygen and gas can be controlled by two separate valve controllers.
The combustion assembly includes a combustion chamber in which combustion of the mixture of oxygen and flammable gas is initiated. The device also includes an ignition assembly which includes a spark plug, a device for generating and sending energy for the spark to the spark plug, an ignition switch, and a radio receiver for receiving a signal from a remote location to initiate a spark. The ignition assembly includes a transmitter for remote detonation of the gases.
The device also includes an injection assembly, which includes an injection tube, which is adjacent to the combustion chamber, which directs the mixture of gases into an underground burrow.
The device also includes a control panel assembly, which includes a control panel and a remote transmitter, with the remote transmitter configured for remote operation of the device. In one configuration of the device the remote transmitter is able to control one or more valves, which allows oxygen and flammable gas to flow into the combustion chamber, as well as to control the initiation of the spark in the ignition assembly from a remote location.
The device can include a mixing tip, which creates a thorough mixing of the oxygen and flammable gas. The device can also include a nozzle tip in the injection tube, which contains a narrowing internal diameter followed by a gradually expanding internal diameter. This constricting flare in the passageway through which the mixture of gases flows is designed to impart a shockwave to the gas and oxygen as the gases are ignited. In one configuration of the mixing tip, the flow of oxygen can serve as an eductor to draw the appropriate flow of flammable gas into the oxygen stream, which contributes to thorough mixing. The mixing tip can further include a turbo tip, which is configured to impart a vortex, or a spiraling flow, to the mixture of gases as they enter the combustion chamber. When the gases pass from the combustion chamber they pass through a nozzle tip which has reduced diameter and directional vanes to further impart vortex flow to the mixture of gases.
In one configuration of the device, the valve assembly is contained in a valve housing with the combustion ignition and injector assemblies located in a device tip. In this configuration, the valve housing and the device tip are connected by conduits which contain a line for flammable gas, a line for oxygen, and a line which contains the electronics line to the ignition assembly. In this configuration, the valve housing is held in a spaced apart relation from the device tip and the two are joined by extended lines containing flammable gas conduit, oxygen conduit, and electronics line.
The device can also include a thermal switch in the combustion chamber for the purpose of cutting off the flow of gases when the temperature of the combustion chamber exceeds a pre-selected temperature. The device can further include a check valve in the combustion assembly for the purpose of preventing the gases in the combustion chamber from being ignited and from burning material coming from outside of the device itself. This can occur when gas has been injected and ignited into a section of burrow, and flammable material in the burrow is still being burned. Then, when gas begins to be injected into another opening into the same burrow system, it is possible for the gas to be ignited by the burning material in the burrow rather than from the spark plug. In that case, the flow of new gas would be cut off by the check valve or the thermal switch.
The panel assembly can further include a status board on which various parameters of the device can be displayed. This includes information about the status of the gas and oxygen valve, power to the unit, and the battery.
One embodiment of the device includes a configuration in which the oxygen and the flammable gas are not mixed together until the combustion chamber, which is adjacent to the nozzle tip.
One embodiment of the device includes structure such as a mixture tip and a turbo tip to induce a vortex flow into the device, coupled with a constriction in the exit line, which creates a shockwave of combustion in the mixture of gases.
The purpose of the foregoing Abstract is to enable the public, and especially the scientists, engineers, and practitioners in the art who are not familiar with patent or legal terms or phraseology, to determine quickly from a cursory inspection, the nature and essence of the technical disclosure of the application. The Abstract is neither intended to define the invention of the application, which is measured by the claims, nor is it intended to be limiting as to the scope of the invention in any way.
Still other features and advantages of the present invention will become readily apparent to those skilled in this art from the following detailed description describing preferred embodiments of the invention, simply by way of illustration of the best mode contemplated by carrying out my invention. As will be realized, the invention is capable of modification in various obvious respects all without departing from the invention. Accordingly, the drawings and description of the preferred embodiments are to be regarded as illustrative in nature, and not as restrictive in nature.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross sectional view of the device of the invention.
FIG. 2 is a view of the control panel of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
While the invention is susceptible of various modifications and alternative constructions, certain illustrated embodiments thereof have been shown in the drawings and will be described below in detail. It should be understood, however, that there is intention to limit the invention to the specific form disclosed, but, on the contrary, the invention is to cover all modifications, alternative constructions, and equivalents falling within the spirit and scope of the invention as defined in the claims.
The preferred embodiment of the invention is shown in the figures. FIG. 1 shows the burrowing pest control device 10 of the invention which includes a valve housing 12 , a device tip 14 , a handle 16 for carrying the device. The device is generally divided into a valve assembly 50 which is located within the valve housing 12 . Another division is the combustion assembly 52 which is located within the device tip 14 . The injector assembly 54 is also located in the device tip 14 and includes an injection tube 34 and a nozzle tip 76 . In this embodiment of the invention, device tip 14 is held in a spaced apart relationship from the valve housing 12 , and the two are connected by pipes. An oxygen pipe 18 transfers oxygen from the valve housing 12 into the metering and mixing region of the device tip 14 . A flammable gas pipe 20 conducts a flammable gas from the valve housing 12 to the metering and mixing region of the device tip 14 . A third pipe may also be present which houses wires and other electrical components for sending a signal from the valve housing 12 to the device tip 14 .
The valve housing 12 is preferably made of metal, but other materials can be utilized such as a suitable plastic, fiberglass or other material. The gas lines 18 and 20 are preferably made of metal pipe and may be approximately 24 inches long and ½ inch in diameter.
FIG. 1 shows a pipe clamp 22 and a pipe seal 40 which are devices utilized with the gas pipes 18 and 20 . The combustion assembly is shown as 52 and is located in the device tip 14 . The combustion assembly 52 includes a combustion chamber 66 and an oxygen conduit or pipe 18 and a flammable gas conduit or pipe 20 . An ignition assembly includes a spark generator 68 and a spark plug 24 , an ignition switch 70 , a valve controller 96 , and a radio receiver 72 . The spark plug 24 is preferably housed in a spark plug sleeve 26 . The spark plug 24 is electrically connected to the spark generator 68 by an electronics line 100 , and to an ignition switch 70 , as well as ignition control mechanisms in the valve housing 12 , which may be activated from the control panel 74 or from the remote transmitter 44 . A factory-set timed activation switch may also be added. A preferred design of the mixing tip 36 is one in which the flow of oxygen can serve as an eductor 85 , to draw the appropriate flow of flammable gas into the oxygen stream, which contributes to thorough mixing.
Located in the device tip 14 is also a thermal switch 28 , and a check valve 30 . The thermal switch 28 detects the temperature in the combustion chamber 66 and shuts off the flow of gases if the temperature in the combustion chamber exceeds a preset temperature. The temperature in the combustion chamber could exceed a preset temperature if gas has been ignited and dispensed for a period of time sufficient for the injection tube 34 to become hot.
The device tip 14 also includes a check valve 30 . When activated, the check valve 30 prevents the propagation of flame from the combustion chamber or the device tip 14 into the gas line 18 or 20 .
The device can be sized according to the requirements of the particular application, but one advantageous configuration is one in which the injection nozzle tube is made of non-ferrous metal and is a tube approximately 2 inches in diameter.
Sequentially, a valve controller 96 is activated by a controller valve activation switch 102 . The valve controller 96 opens the oxygen valve 46 and the flammable gas valve 48 , and gases flow toward the mixing tip 36 . The gases are mixed in the mixing tip 36 , which encloses the eductor 85 . From the mixing tip 36 the gases flow through a check valve 30 which prevents backflow. From the check valve 30 the mixed gases enter the combustion chamber 66 through a turbo tip which disperses the mixed gases in multiple directions into the combustion chamber 66 . From the combustion chamber, the gases flow through a nozzle tip 76 in which is located a vortex generator 32 . The vortex generator 32 imparts a swirling motion to the gases by use of directional vanes 106 . The directional vanes 106 impart a swirling motion into the mixture of gases coming from the combustion chamber 66 and exiting the nozzle tip 76 . The swirling of the gases creates a vortex effect which extends not only out the device tip as the gases exit the device, but also extends into the combustion chamber and serves to draw the two gases towards the exit of the device tip and to mix them together when in the swirling vortex. The vortex generator 32 , by creating a vortex in the gases, serves to mix the two gases together better and, since the vortex extends into the burrow, the two gases stay mixed together longer, and the stream of flammable gas and oxygen mixing together in a vortex extends for a greatly enhanced distance into the burrow. The vortex also serves to keep the two gases from separating as the distance from the device tip becomes greater. The nozzle tip 76 preferably includes a constricting flare 78 , which is a section in the tubing of the nozzle tip 76 which has a narrowing internal diameter followed by a gradually expanding internal diameter. This constricting flare 78 in the passageway through which the mixture of gases flows is designed to impart a shockwave to the gas and oxygen as the gases are ignited.
Within the valve housing 12 is located a valve controller 96 , an oxygen valve 36 , and a gas valve 48 . Within the valve housing 12 is also located a radio receiver 72 for receiving a signal from the remote transmitter 44 . From the remote transmitter 44 a signal can be received to begin the flow of gases and a separate signal can be sent to activate the ignition of the gases. When the gases have flowed for a sufficient time, a signal to ignite is sent from the remote transmitter 44 . The radio receiver sends that signal to the spark generator 68 , which uses the battery 80 to generate a spark at the spark plug 24 .
On the valve housing 12 is located a gas line connection 82 and an oxygen line connection 84 . To these connections are attached an oxygen hose 62 and a gas hose 64 which connect the device to an oxygen source 58 and a gas source 60 .
FIG. 2 shows the configuration of the control panel assembly 56 . The control panel assembly 56 includes a control panel 74 , with a unit off/on switch 94 for turning the unit on or off. Also shown on the control panel 74 is a gas line connection 82 and an oxygen line connection 84 for manually attaching the gas and oxygen line. The control panel 74 can include a power indicator 86 in the form of a light, which would indicate if the power to the unit is activated or not. A flow indicator 88 , battery indicator 90 , and a spark indicator 92 , may also be present and form a status board 104 as part of the control panel 74 .
In the following description and in the figures, like elements are identified with like reference numerals. The use of “or” indicates a non-exclusive alternative without limitation unless otherwise noted. The use of “including” means “including, but not limited to,” unless otherwise noted.
While there is shown and described the present preferred embodiment of the invention, it is to be distinctly understood that this invention is not limited thereto, but may be variously embodied to practice within the scope of the following claims. From the foregoing description, it will be apparent that various changes may be made without departing from the spirit and scope of the invention as defined by the following claims.
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The invention is BURROWING PEST CONTROL DEVICE, while mixing together oxygen and a flammable gas and injecting it into an underground burrow. The device includes the feature of being operated from a remote position, a vortex injection of the gases, and a device for generating a shockwave to propagate combustion throughout the stream of mixed gases.
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FIELD OF THE INVENTION
The present invention relates generally to an apparatus used to treat semiconductor wafer surfaces. More particularly, the present invention is an apparatus, for treating spinning semiconductor wafer surfaces, in which there is provided a head, for contacting the surface of the wafer, having attached thereto a first means for setting the head against the wafer surface with a selected predetermined force and a second means for temporarily and selectively altering the selected predetermined force set by the first means without altering the setting established by said first means.
BACKGROUND OF THE INVENTION
Production of semiconductor devices requires the treatment of a semiconductor wafer with a number of chemical, mechanical or chemical-mechanical processing steps.
During these processing steps, even minute changes or variations in the wafer surface can produce effects that can adversely affect later processing steps and thus affect the reliability of the devices formed in the wafer. For example, such changes and variations can fail to remove contaminants or otherwise fail to appropriately condition the surface of the semiconductor wafer such that later processing steps are interfered with. When such processing steps fail they usually result in either instant or premature failure or long term degradation and shortened life of some or all or the devices produced in the wafer.
Certain of these processing steps require the use of an apparatus that can place a head, carrying a pad or brush, steeped in a suitable chemical such as a cleansing agent, adjacent to or against the surface of the wafer to treat, e.g., clean, or otherwise condition, the surface of the wafer.
In all such presently available apparatuses the force between the brush or pad carrying head and the surface, i.e., the head pressure, is substantially unknown and uncontrolled. Further the prior art apparatuses lack any means for consistently setting, maintaining or monitoring the head pressure. This lack of control of the head pressure is inherent in the prior art apparatuses because their rigid design renders them incapable of either achieving or consistently maintaining a known head pressure.
The present inventors have now found that many of such wafer processing steps require, for optimum results, that distinct head pressures be maintained and that for most process steps that the head pressure be, at least, a selected minimum pressure. The present inventors have also found that by doing so more consistent production results can be obtained.
The present inventors have also found that while many steps require this minimum head pressure other steps require that the head pressure be altered from this minimum pressure.
Therefore, it is most desirable that such semiconductor devices be fabricated using an apparatus that is capable of producing and maintaining different selected head pressures as required by the process steps.
It is also desirable, for many process steps, that the apparatus be readily and quickly capable of returning the applied head pressure to a preselected minimum head pressure.
SUMMERY OF THE PRESENT INVENTION
The present invention provides a head processing apparatus having a first means that can be set to establish and provide a selected head loading or pressure, i.e., the loading or pressure between a brush or pad carrying head and a wafer surface, and a second means that can be activated to temporarily alter or adjust the selected head pressure without affecting the setting of the said first means that establishes the selected head pressure such that when said second means is deactivated, the apparatus will instantly return to the selected head pressure established by said first means.
The present invention by providing said first and second head loading means maintains better processing conditions thus causing all the processing steps performed by the apparatus to be performed under optimum and repeatable conditions.
In this way, the present invention, achieves better more consistent results and a lower defect or scrap rate.
More particularly, the present invention accomplishes these desirable results in a semiconductor wafer chemical mechanical treatment apparatus having a sectional extended arm carrying a head. The sectional arm is comprised of a fixed yoke and an elongated arm positioned in said yoke on a pivot. The elongated arm carries a first means thereon for establishing and maintaining a given loading or pressure on the head. A second means, is positioned on the yoke, adjacent to the elongated arm for temporarily altering the given loading or pressure on the head established by the first means without disturbing the setting of the first means such that when the second means is reset the given head load or pressure established by said first means is automatically restored.
Therefore it is an object of the present invention to provide a new wafer treatment apparatus which is provided with first means that can be set to create a selected head pressure between a brush and pad carrying head and a wafer surface and with second means for altering the selected head pressure as required by the process without altering the setting of the first means.
These objects, features and advantages of the present invention will be become further apparent to those skilled in the art from the following detailed description taken in conjunction with the accompanying drawings wherein:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an isometric top view of the wafer processing apparatus of the present invention.
FIG. 2 is an isometric view of the bottom of the head assembly of the wafer processing apparatus of the present invention as shown in FIG. 1 .
FIG. 3 is a partial sectional view of the head assembly of FIG. 1 .
FIG. 4 shows the wafer holding chuck of FIG. 1 having a special load cell plate thereon.
DESCRIPTION OF THE PREFERRED EMBODIMENT
With reference now to FIGS. 1, 2 and 3 a wafer processing apparatus 10 employing the present invention will be described.
The apparatus 10 includes a rotary chuck 12 supported by the shaft 14 of motor 16 as is well known to the art. A semiconductor wafer 18 is supported on chuck 12 and maintained centrally thereon by a plurality of clips or edge supports 20 . The wafer chuck is mounted on the motor 16 so that the wafer 18 can be spun around its axis as shown by arrow 19 .
Adjacent the chuck 12 there is positioned a hollow vertical post 22 coupled to a reciprocating motor 24 via a shaft 25 which extends from the motor 24 , up through the post 22 , to connect to one end of a cantilevered assembly 26 supported on the post 22 . The other end of the cantilevered assembly 26 is provided with a brush head assembly 27 formed of a descending rod 30 having a passage extending along its vertical axis. The rod 30 carries, at its lower end, a head 32 provided with means 34 for mounting either a brush or pad 35 thereon.
The motor 24 is designed to move the assembly 26 in a reciprocating arcuate path across the surface of the wafer 18 , as shown by the double headed arrow 36 , and to step the assembly 26 up and down, as shown by the double headed arrow 37 so that the brush 35 can be positioned with respect to the wafer surface as required by the process.
When the wafer is being spun by the motor 16 turning the chuck 12 , the brush 35 , is stepped, by the motor 24 , into position so as to touch the wafer surface and then moved, by the same motor 24 , back and forth in a series of reciprocating arcuate paths across the spinning wafer surface. Because the wafer is spinning and the brush or pad is being moved across the surface of the wafer, the entire surface of the wafer will pass under the head and is thus treated as required by the process.
In the prior art, the assembly 26 was rigid, and therefore the amount of pressure applied by the brush 35 to the wafer surface was solely based on position of the brush 35 with respect to the wafer surface as determined by the stepping motor 24 . As is well known to the art, the stepping motor 24 moves the head assembly toward the surface of the wafer in fixed incremental steps. To assure that the head did not crush the wafer surface the prior art limited the position of the head to a preset position above where the surface the wafer was expected to be.
Because the stepping motor moves only with incremental steps, these limits would in some instances cause the motor to stop the head so that the brush 35 was above and not touching the wafer surface, in other cases the limits would cause the brush 35 to barely touch the wafer surface and in still other case the brush 35 would be stopped in full contact with the surface but without knowing if what pressure, if any, was being applied to the wafer surface. Thus, in the first above described case, little or no pressure would exist between the brush 35 and the wafer surface and, in the other cases, the pressure applied would be unknown. Further, in those cases where the head did contact the wafer surface if the surface was warped or undulating the applied head pressure would vary as the head passed over the warped or undulating surface.
If the treatment being performed required a minimum amount of pressure greater than that actually being applied, the treatment could either take substantially longer than expected or could even be ineffective. On the other hand if head was positioned such that too much pressure was applied to the wafer surface the wafer surface could be damaged.
Because of this uncontrolled reliance on the positioning of the head by the stepping motor the pressure applied between the head and the wafer surface was effectively uncontrollable.
Later techniques attempted to more accurately position the bead with respect to the wafer surface by using proximity senors such as laser beams but again, because of the limiting incremental steps imposed by the stepping motor, the pressure applied by the head arm remained unknown and indeterminable.
The present invention avoids these problems of the prior art by designing the assembly 26 as a yoke supported pivoting arm carrying a pivoting head assembly and a primary means for providing the brush 35 with a selected brush to wafer pressure or loading whenever the brush is placed in contact with a wafer surface. Once this primary mean has established the selected brush to wafer pressure, then whenever the stepping motor places the brush 35 anywhere within a specified distance from the wafer surface that the brush 35 will bear on the wafer surface with the known preestablished loading or pressure.
Still further the present invention provides secondary means which when activated, can selectively alter the loading or pressure between the brush and the wafer surface established by the primary means without disturbing the setting of the primary means that established the preload. This means that the brush to wafer loading or pressure can be altered on the fly at any time during the process and also means that when the secondary means is deactivated that the pre-loaded brush head to wafer pressure established by the primary means will automatically be restored.
The head assembly 26 , of the present invention, achieves these desirable results by use of a cantilevered, sectional assembly 40 maintained at a right angle to the post 22 and extending horizontally therefrom. This sectional assembly 40 comprises a yoke 41 , having a body portion 41 a and bifurcated arms 41 b and 41 c , and a pivoting, extended, brush head carrying, elongated bar arm 42 . Preferably both the yoke 41 and the arm 42 are made of stainless steel. This bar arm 42 is positioned between and supported in the yoke arms 41 b and 41 c by a pivot pin 43 passing through the center of the bar arm 42 and the end of the yoke arms, 41 b and 41 c . Thus the bar arm 42 has a proximal end 42 a generally positioned between the bifurcated arms 41 b and 41 c and a distal end extending past the ends of the bifurcated arms 41 b and 41 c . It is of course understood that the pivot pin 43 is made such that the bar arm 42 can rotate within the yoke arms 41 b and 41 c . The yoke body 41 a is also provided with an opening 41 d therein so that the yoke may be secured to the shaft 25 of the motor 24 passing up through the hollow center of the post 22 .
As shown in the FIGS. 1, 2 , 3 , and 4 , the bar arm 42 has its proximal end 42 a enclosed between the bifurcated arms 41 b and 41 c and its distal end 42 b extending, i.e.; cantilevered, past the ends of the bifurcated arms 41 b and 41 c . The distal end 42 b of the bar arm 42 is provided with an opening 42 d in which there is positioned a descending shaft 30 having the head 32 thereon. The top of the descending shaft 30 is connected to a cross bar 44 located in the opening 42 d . This crossbar is supported in the opening 42 d by locating it between a pair of shoulder screws 45 . These shoulder screws 45 are designed to permit the shaft 30 to swing or pivot in the opening 42 d.
As especially shown in FIG. 2, the bar 42 has a first means for applying a selected force on the brush head 32 when the brush head is brought close to a wafer positioned on the chuck 12 . These first means comprise the one or more sliding weights such as weights 46 a and 46 b hung on the bottom of the bar 42 . Each of these weights 46 a and 46 b is provided with a pair of inwardly projecting ears 47 that hang in longitudinal grooves 49 positioned along the lower edge of the bar 42 . The weights 46 a and 46 b are further provided with screws 48 a and 48 b passing there through so that the weights may be locked in position anywhere along the bar 42 as will be further explained below.
The proximal end 42 a of the bar arm 42 is positioned between the bifurcated arms 41 b and 41 c such that is beneath and spaced from a second means, such as an electromagnet 49 , for selectively altering the amount of head pressure applied by the weighs 46 a and 46 b . The electromagnet 49 is supported a fixed height above the proximal end 30 a of the bar arm 30 by hangers 60 , which are secured atop the yoke arms 41 b and 41 c . Because stainless steel is nonmagnetic, it is necessary that an iron plate 42 e be secured to the proximal end 42 a of the bar 42 . With this plate 42 e is in position and the electromagnet is activated the plate will be pulled up causing the distal end 42 b of the bar 42 to press harder against the surface of the wafer 18 . If, instead of being made out of iron, the plate 42 e is formed of magnetic material then the electromagnet can, by selecting the direction of current flow there though, be used to either attract or repel the proximal end of arm 42 and thereby increase or decrease the pressure applied by the head 32 on the wafer surface. The length of the entire head assembly 26 , i.e., the yoke 41 and the arm 42 , is, as shown in the FIG. 1, sufficient to position the head 32 over the center of the rotary chuck 12 .
Positioned on the distal end of the arm 42 is a “T” shaped drip arm 51 having an extended leg end 51 a cantilevered over the brush head. This cantilevered end 51 a supports a hose 52 coupled to a suitable source 52 a of the fluids required in the wafer treatment process as is well known to the art. The cross bar Sib of the T shaped drip arm 51 spans across and is fixed between the bifurcated arms 41 b and 41 c of the yoke 41 . The extended leg of the “T” is of a length as to position the hose 52 over the port 30 a passing along the axis of the shaft 30 such that the fluids passing through the hose 52 will be delivered through the brush 35 onto the surface of the wafer being treated, as will be discussed further below.
The operation of the equipment will now be described. In present day wafer treatment processes, ideal brush to wafer pressures for various steps have been established either empirically or by calculation. When the apparatus of the invention is to be used for a selected process, the brush head locking screws 50 and 51 are loosened to allow the head 32 to swing in the pivot screws 45 . The wafer chuck 14 has a special load cell plate 62 placed thereon. This plate 62 is designed to have, in its center, a load cell 63 electrically coupled to a detection meter 64 by wires 65 . The plate 62 is designed to carry the load cell 63 such that the upper surface of the load cell 63 is positioned at same height as the surface of a wafer 18 placed on the chuck 12 . The head 32 is then moved vertically so that it is placed in contact with the surface of the pressure detector or load cell 63 . Once the head 32 is in the desired position the weights 46 a and 46 b are moved along the arm 42 to pivot the bar 42 and establish a selected head to surface pressure.
For example, it has been found that, for effective cleaning of a wafer surface, a head to surface pressure of 0.75 ounces/inch 2 is especially beneficial. It is, of course, understood that for other processes a greater or lessor pressure may be required.
One acceptable pressure sensor that has been used for measuring the head to wafer surface pressure is a 0 to 5 pound/inch 2 load cell, model LCGC-5, sold by Omega Engineering Inc. of Stamford, Conn. This load cell is used in conjunction with a model DP25S load cell meter also sold by Omega Engineering Inc.
Although, for purposes of illustration and ease of description, the pressure sensor 63 is, as shown in FIG. 1, positioned adjacent the chuck 12 , in production conditions, it is preferred to use a special pressure sensor holder that can be substituted for the wafer 18 on the chuck 12 .
Once the desired head to wafer surface pressure has been established, by moving the weights 46 a and 46 b , the weights are locked in position, the head raised off the surface of the pressure sensor. If the sensor is on the chuck 12 then the entire pressure sensor holder is removed off the chuck 12 and replaced thereon by the wafer that is to be treated.
Because the pressure sensor, whether used in the pressure sensor holder positioned on the chuck 12 or positioned adjacent the chuck 12 , has its upper surface in the same plane as the surface of a wafer 18 held in chuck 12 the brush will be, when the assembly 26 is again positioned over a wafer in the chuck as it was positioned over the pressure sensor, in contact with the wafer surface with the same force as it contacted the pressure detector 63 .
Thus once a wafer 18 , to be treated, is placed on the chuck 12 , the chuck is set spinning, the assembly 26 is swung over the spinning wafer and the desired fluid is passed through the hose as the brush is lowered against the wafer surface. Because this lowering of the brush is accomplished by the same stepping motor used to set the brush in position over the pressure sensor surface, the brush 35 will be positioned at the same distance from the wafer surface as it was positioned from the surface of the pressure head. Thus the brush will bear on the wafer surface with the same pressure that it bore against the pressure head, i.e., the pressure established by positioning the sliding weighs 45 and 46 on the arm 42 . In this way a known brush to wafer pressure can be established and maintained during the process steps.
Once the brush arm 35 is in contact with the rotating surface of the wafer 18 , the brush is moved, in the above described arcuate path, so that it will treat the entire wafer surface at the preestablished pressure.
If we now assume that the next process step requires an increase in the pressure applied between the brush and the wafer surface, such an increase can easily be achieved by activating the electromagnet so as to attract the iron plate 42 e . By attracting the plate 42 e the proximal end of the arm 42 is raised and the distal end is pivoted down placing the brush against the wafer surface with greater force.
If it is found desirable to either increase or decrease the pressure applied between the brush and the wafer surface the iron plate 42 e should be replaced by a fixed magnet. By so substituting a fixed magnet for the iron plate and by changing the direction and amount of current through the electromagnet 49 the applied head to surface pressure can be either increased or decreased. As is well known, when a current is passed through an electromagnet it creates magnetic forces that will either attract to or repel another adjacent magnet. In this way the fixed magnet, substituted for iron plate 42 e can be either pulled up toward the electromagnet 49 or repelled therefrom. These forces either pull or push the proximal end 42 a of arm 42 , positioned beneath the electromagnet, thus pivoting the distal end 42 b in the opposite direction. By so pivoting the bar 42 around the pin 43 , the brush will be either pushed harder against the wafer thus increasing the brush to wafer surface pressure or be pulled away from the wafer surface thus reducing the brush to wafer pressure.
In this way the electromagnet 49 in conjunction with a magnetic plate can be used to alter the pressure between the brush head and the wafer surface established by the weights 46 a and 46 b.
Once this altered pressure is no longer required, the current, applied to the electromagnet is cut off and causing the preestablished pressure created by the weights to be automatically restored.
This completes the description of the preferred embodiment of the invention. Since changes may be made in the above construction without departing from the scope of the invention described herein, it is intended that all the matter contained in the above description or shown in the accompanying drawings shall be interpreted in an illustrative and not in a limiting sense. Thus other alternatives and modifications will now become apparent to those skilled in the art without departing from the spirit and scope of the invention as set forth in the following claims.
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A semiconductor wafer chemical mechanical treatment apparatus having a sectional extended arm carrying a head. The sectional arm is comprised of a fixed yoke and an elongated arm positioned in said yoke on a pivot. The elongated arm carries a first means thereon for establishing and maintaining a given loading or pressure on the head. A second means, is positioned on the yoke, adjacent to the elongated arm for temporarily altering the given loading or pressure on the head established by the first means without disturbing the setting of the first means such that when the second means is reset the given head load or pressure established by said first means is automatically restored.
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CROSS REFERENCE TO RELATED APPLICATION
[0001] The present application is related to U.S. Provisional Patent Application No. 60/113,926, filed on Dec. 24, 1998 and entitled METHOD FOR ERROR COMPENSATION IN AN OFDM SYSTEM WITH DIVERSITY.
BACKGROUND OF THE INVENTION
[0002] The present invention is directed to a method for error compensation in a communication transmission environment. More particularly, the present invention is directed to a method for providing for channel compensation in a multi-carrier tone environment whereby the method minimizes the number of pilot tones needed to estimate a complex channel coefficient.
[0003] Wireless communications have become a popular mode by which users can exchange voice and/or data information. In fact, wireless communications, which initially were thought to be primarily useful for establishing mobile communication systems, have also become a popular option for extending access to subscribers without requiring the outlay of additional resources and labor to put wireline configurations into place. For example, it has been proposed to provide a service referred to as “fixed wireless” as an. alternative to wireline connections into local exchange carriers. The fixed wireless service provider would then be able to provide local service to a fixed location, for instance, a subscriber's home, without having to incur the expense of placing cables or wires to each subscriber in a geographic region.
[0004] As wireless communications have become more popular, service providers have explored different options for transmitting and receiving these communication signals. In so doing, designers have taken into account the possible negative impacts of wireless communications such as those arising from multi-path fading. It has been determined that orthogonal frequency division multiplexing (OFDM) is an effective scheme for combating adverse effects of multi-path fading. In OFDM a plurality of tones or subcarrier frequencies are used to carry information via an over-the-air channel. FIG. 1 illustrates how a plurality of carrier tones f 1 to f k constitute the carrier signal and that signal can be produced at time intervals with the interval selected to avoid the impact of certain delays arising in the communication path. Modulation of information onto the carriers can be performed by a simple inverse discrete Fourier transform (IDFT) which can be implemented very efficiently as an inverse fast Fourier transform (IFFT). In such an arrangement, a receiver needs a fast Fourier transform (FFT) device in processing the received signal to reverse the modulation operation. The spectrum of the subcarriers in the OFDM environment is permitted to overlay to some degree since the orthogonality relationship between the signals provides the appropriate separation between the carriers.
[0005] Both coherent and incoherent modulation schemes can be used in OFDM. Since coherent schemes have better performance, they are used in most OFDM systems. In practice, the transmitted symbols transported on the OFDM signals on the over-the-air channel are disturbed by the physical channel which is said to include the transmitter, the propagation channel, and the receiver itself. The disturbance can be represented or characterized in the form of a multiplicative complex coefficient. In the case that the bandwidth of an OFDM channel is sufficiently narrow, one may assume a model with a complex coefficient is common to all the subcarriers (or tones) across the channel. This complex coefficient has to be estimated and then removed or compensated for.
[0006] One well known technique for estimating the physical channel coefficient is to transmit one or more pilot symbols along with information symbols on the carriers. By pilot symbols we mean a known symbol at a particular tone. At the receiver, knowing the symbol that is expected to be received on a given tone, the receiver can estimate the complex coefficient. The receiver can then apply the inverse of this coefficient to the other information symbols, thereby compensating for channel disturbances to the information symbols. Following the compensation process, signals from different receiving branches are combined for diversity gain. Decisions as to the content of the information symbols are made based on the combined signals.
[0007] Even using this pilot symbol detection technique, symbol errors may arise because the received pilot signals are contaminated by noise. This means that the detected coefficient estimation is inaccurate to some extent. It is expected that the noise will not have the stable characteristics that the remainder of the channel coefficient may have and in fact may vary with time and frequency. Thus, it would be beneficial if there was some way to reduce the effect of this noise since the inaccuracy it introduces will typically degrade the system performance by 3 dB in terms of the signal to noise ratio (SNR).
[0008] A number of solutions have been considered in attempting to overcome this problem. One solution is to introduce additional pilots into the system. By using additional pilots there are further reference points for detecting the complex coefficient and noise terms. The drawback from this technique is that with each pilot used the spectrum efficiency of the spectrum is reduced since the number of information carrying tones is reduced. Simply put, additional pilots require additional channel space. A second option is to boost the power of the pilot tone so that the signal-to-noise ratio of the pilot signal is higher than that of the data signals. This would mean that upon detection of the pilot tone it would presumably be a more accurate detection of the complex coefficient as the impact from noise would be smaller or reduced. This solution has its own cost in that as one boosts the power of the pilot tone there is a higher likelihood that there would be interference with adjacent tones.
[0009] It would be beneficial if there was a technique for improving the channel compensation operation to take into account the presence of noise without significantly reducing channel capacity or increasing the probability of interference between carrier tones.
SUMMARY OF THE INVENTION
[0010] The present invention provides a method for channel compensation which improves upon the known system of employing pilot tones for estimation of the complex coefficient of the transmission channel. More particularly, the present invention provides a technique by which a pilot tone is used to generate an initial correction coefficient. This correction coefficient is used in connection with the processing of information tones whereby a subset of all of the information tones are treated as if they were pilot tones when it is determined that the probability that their symbols have been accurately detected exceeds a particular threshold. These are so-called pseudo pilot tones. These pseudo pilot tones increase the reference base for the coefficient calculation so that it is as if the system is utilizing multiple pilot tones for generating the complex coefficient of the channel and yet it still keeps a higher spectrum efficiency since these pseudo pilot tones carry information over the channel. The pseudo pilot tones are used to generate an enhanced or secondary error estimation which in turn is used to correct the information signals in a manner that has been detected to be more accurate. Thus, the impacts of the channel are more completely compensated using this enhanced or secondary error estimation based on actual information carrying tones.
[0011] The present invention maintains spectrum efficiency while improving estimation of the complex coefficient of the channel which in turn improves the symbol error rate without need of introducing additional sources of interference.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] [0012]FIG. 1 provides an illustration for understanding a multi-tone carrier signal.
[0013] [0013]FIG. 2 illustrates a system in which the present invention can be employed.
[0014] [0014]FIG. 3 illustrates a block diagram of a signal processor arrangement in accordance with an embodiment of the present invention.
[0015] FIGS. 4 to 6 are plots for showing the results of a simulation of the present invention.
DETAILED DESCRIPTION
[0016] In accordance with an embodiment of the present invention, a receiver system has a plurality of antennas that are diverse so as to maximize the receipt or capture of signals from a transmitter. These multiple antennas may be placed in different orientations with respect to one another so as to capture the same sepal transmitted from the base station, but in different positions thereby adapting to the multiple paths that the signal may traverse between the transmitter and the receiving station. An example of such an arrangement of diverse antennas is illustrated in a block diagram form in FIG. 2. Here a system of four antennas is shown. This should not be taken as a restrictive number. More or fewer antennas may be used in a given system depending on the multi-path fading which might be expected from the channel. All of the antennas are coupled to a signal processor arrangement which takes the signals captured by the respective antennas and ultimately combines them into a meaningful information signal representative of the information sent from the transmitter. The present invention involves itself with the processing of the captured signals as it is performed in the signal processor 200 .
[0017] In general, the present invention takes advantage of the known technique of utilizing a pilot tone on a given one of the multiple tones to establish a base line or initial complex coefficient representative of the channel's characteristics. Say for example, a known symbol was to be transmitted on frequency F 1 on a first transmission in the OFDM system, then F 1 would be considered a pilot tone and the receiver processing would be looking for that specific symbol on the pilot tone on the captured first transmission signal from each of the multiple antennas. A compensation for a given antenna, as each antenna has its own path or channel between that antenna orientation and the transmitter, would include an initial calculation of a complex coefficient for the channel generated by comparing the detected symbol on the pilot tone versus what is expected to have been placed on the pilot tone. This comparison yields a primary or a first stage complex coefficient channel. The present invention then improves upon this known technique by looking at information signals captured by the same antenna, such as those on frequencies F 2 to F 6 and determining that some subset of those symbols and respective carriers can be treated as if they were pilot tones. That is, an estimation is made of the probability that the signal processor has correctly identified or detected the information symbol on that information carrier using the corrected version of the information signal generated from the primary complex coefficient of the channel. If there is a sufficient probability that the detected symbol does correspond to the symbol transmitted on that information carrier, then that information carrier is treated as if it were a pilot tone and the received signal is, compared to the ideal symbol to create an increased number of reference points for calculation of the complex coefficient. As more pseudo pilot tones are used in connection with a given receiving antenna, the effect of the noise on each of the frequencies can be factored into the calculation with the hope being that the impact of the noise as a separate element can be reduced.
[0018] [0018]FIG. 3 illustrates in block diagram form a processing arrangement which performs this series of operations. First, for reference purposes, it is assumed that there are “k” receiver antennas. It is also assumed that there are N carrier tones. The signals received by the various k antennas are represented as S( 1 ) to S(k). These signals impliedly include all N tones captured by their respective antennas.
[0019] The processing arrangement of the present invention operates in at least two stages, 300 and 350 . The first stage employs the well known technique of detecting some aspect of the channel characteristics based on a known pilot symbol. Here the first stage is shown as having discrete processing elements 201 1 to 201 k for each of the k antennas. While the drawing shows discrete processing for symbols received on each of those antennas, it is not necessary for purposes of this invention that the elements performing that processing be in fact physically discrete elements. Looking for example at the element 201 a, a pilot detector 203 , detects the symbol on the pilot tone and an error estimator 204 , performs error estimation based on comparing the detected symbol to the expected symbol on the pilot tone. The information carriers on the first antenna are subjected to a time delay device 206 which delays the signals S( 1 ) for a time that corresponds to the time period necessary for the error estimation operation to be performed. The delayed signal and the error estimation (1) are provided to an error correction device 207 1 which generates a corrected version of the information symbols captured by that antenna. This corrected version of antenna 1's symbols is represented by (1). As this error correction operation entails additional processing time, a second delay device 209 1 delays the entire captured signal (S( 1 )) for the period of time needed to allow all of the other processing to occur before the delayed signal is transmitted to the second stage 350 of the processing operation As is suggested by FIG. 3, these first stage processing operations can be performed with respect to each of the k antennas.
[0020] As a consequence, the second stage of the operation receives corrected versions of the captured signals of each receiving antenna and the captured signals themselves. All of this information is provided to a pseudo pilot selector, 255 . The pseudo pilot selector's job is to select among the information signals for each of the captured signal sets to determine a subset of information signals which can be treated as if they were additional pilot tones even though they in fact carry information. This can be achieved by determining a probability that a symbol detected from a given information carrying tone is the correct symbol and corresponds to that transmitted. When there is a high degree of certainty or a sufficient degree of certainty, namely that the probability exceeds a satisfactory threshold, then that information carrier can be included in a reference set of information carriers which will have an impact on a second calculation of the channel coefficient. In this instance, the second stage performs a second error estimation with second error estimator 260 , based on those carrier signals which have been identified as pseudo pilots, that is carriers in which the system has a high degree of confidence it has accurately detected the information carried on those tones. Once the secondary error estimation factor, (1), is detected, then the information signal captured on that respective antenna, here S( 1 ), having been delayed for a time period necessary to ascertain this secondary error correction, is subjected to a correction with second error correction device, 270 1 . This secondary error correction provides an enhanced compensation for channel characteristics and this enhanced compensated signal is transferred to the diversity combiner 375 where the system picks up the processing that was done in the art for combining information signals from a plurality of diverse antennas. As can be seen from the drawing figure, separate elements can be provided in connection with each of the diverse antennas in the second stage as well. These elements need not be discrete and separate elements, however.
[0021] The selection of the pseudo pilot signals relies upon a presumption that the system can identify those tones at which the difference between the estimate of a symbol and the true symbol on that tone, which is simply δ i (k)=δ i (k)−c i is so small that the estimated datapoint i (k) remains inside the correct decision boundaries for c i (that is, a correct decision has been made), the coefficient can be estimated using the signal associated with this datapoint, that is,
α ~ i ( k ) = s i ( k ) c i * c i 2 = α ( k ) + Δ i ( k ) Equation 1
[0022] For N data points or OFDM tones, the average value of the coefficient is
α ( k ) = 1 N ∑ i = l N s i ( k ) c i * c i = α ( k ) + 1 N ∑ i = l N Δ i ( k ) Equation 2
[0023] The error term with a factor of 1/N indicates that a more accurate estimate can be obtained. However, the assumption that all signals result in correct decisions is an unrealistic and unreasonable one. In reality, each data point has a probability that it will lead to a correct decision. That is, given a data point, it may lead to a correct or wrong decision. Furthermore, if all the correct decisions can be obtained, there is no need to reduce the estimation error.
[0024] The probability of leading to a correct decision is a conditional probability, which is normally written as p 1 =p[ (k)=μ|c=μ] (that is, the probability that the estimated symbol is μ given that the symbol μ is transmitted). If one is able to pick those signals from the captured signal having a higher conditional probability amongst all the signals, one should be able to use above equation 2 where N would correspond to the number of picked signals.
[0025] An additional factor comes into play where there are multiple diversity branches that can be used for selecting the suitable signals. If the signals from all the branches, s i ( 1 ), s i (k) lead to the same decision (that is, they are within the same decision boundaries) this decision should have a higher probability to be correct than in cases that they do not. That is, it is possible to look at a given tone over a plurality of the antennas and determine if the detected value of that information symbol on that tone matches across those diverse antennas. Where there is such a match, there is a higher probability that the detected symbol on that carrier tone in fact corresponds to the transmitted symbol. Thus, one can use this diversity branch information to select a set of symbols on given diversity antennas as pseudo pilot tones since they have the appropriate level of probability that they correspond to the correct or transmitted symbol. This permits the same type of improvement to arise in the compensation scheme as would arise where multiple pilot tones are employed, however, it avoids taking up unnecessary channel capacity in gaining this improvement.
[0026] Simulation results generated in testing out this operation may be helpful for understanding the impact of the present invention.
[0027] A number of numerical examples in terms of symbol error rate (SER) versus signal-to-noise ratio (SNR), are given here to illustrate the improvement by using the data-aided method. FIG. 4 shows the SER performance against the. SNR for 16-QAM modulation with two-branch (K=2) MRC under Gaussian channel conditions. In the simulations, two complex terms are applied to the received signals at the two branches, respectively, to emulate the complex coefficients. For the SER curves with estimation errors (i.e., |Δ(k)|>0), the SNR of the pilot is the same as that of the data. By comparing the curve without estimation error with that obtained by using conventional method, the degradation in SNR is about three decibels at high SNR. The SER curve obtained by using the data-aided method shows that the loss in SNR is cut at least by two decibels. FIG. 5 illustrates the SER performance as a function of the Ricean K Factor, where SNR per bit is 15 dB. The results show that the performance improvement by using the data-aided method is more substantial as the value of the Ricean K factor increases.
[0028] The final example given here is a case where the parameters used in the simulation are close to the values in a practical environment where a fixed wireless access network may operate. In the simulation, the Ricean K factor is set to be five. The SNR of the pilot signal is three decibels higher than that of the data signals. The number (3 dB) accounts for the fact that the corner symbols of the 16-QAM constellation are used for pilots and their power is 2.6 dB higher the average power of 16-QAM signals. The results are shown in FIG. 6, from which two observations can be made:
[0029] 1 By comparing the SER curve without estimation error with that obtained by using conventional method, the degradation in SNR is at least two decibels at high SNR;
[0030] 2. The SER curve obtained by using the data aided method shows that the improvement in terms of SNR is more than one decibel over the case of the conventional method. In effect, the loss in terms of SNR due to the entire error compensation process is less than a decibel.
[0031] In summary, the present invention provides a technique which builds upon the technique of using pilot tones to detect a complex coefficient of a channel in that it selects from a plurality of information carrying tones, those tones which can operate as pseudo pilot tones. Those pseudo pilot tones can then be employed in an error estimation and an error correction operation which reduces the overall effect or impact of noise on the calculation of the complex coefficient for the channel.
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A method provides for an improved compensation Fourier channel characteristics in a wireless communication embodiment. The method identifies one or more information carriers as pseudo pilot tones whose information may be realized to enhance the determination of the complex coefficient of the communication channel.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a mobile machine, in particular an industrial truck or a fork lift truck, having a chassis and an operator's cab located on it by a suspension system.
2. Description of the Prior Art
Operators of mobile machines are frequently subjected to significant vibration stresses because the machines are not equipped with a suspension system. Fork lift trucks in particular normally have no suspension elements between the frame and the chassis. When the mobile machine travels over bumps or depressions, whole-body vibrations can be transmitted to the driver. These vibrations are then damped only by the driver's seat. In machines of the prior art, the operator's cab is mounted on steel-rubber bearings, which of course reduces the vibration load to some extent, but still lets through significantly more vibrations for the driver than are desirable.
Cabs mounted on suspension systems have recently become common on utility vehicles and agricultural tractors.
The journal “Noise & Vibration Worldwide,” November 1997, pages 17 to 26, contains a scientific article on the development of suspended cabs for fork lift trucks. In the right-hand column on page 22, the above referenced article proposes replacing the four steel-rubber bearings that normally connect the cab with the chassis with four metal springs and shock absorbing elements. One embodiment of this suspension system is illustrated in FIG. 5 on page 24. The suspension system proposed in the above-referenced article significantly damps the vibrations that are transmitted to the driver's cab, although an even more effective damping of impact loads would be desirable.
The object of the invention is therefore a mobile machine in which the impact load on the operator's cab is reduced even further.
SUMMARY OF THE INVENTION
The invention teaches a mobile machine having a chassis and an operator's cab located on it, in which there are one or more pneumatic or hydropneumatic suspension elements between the chassis and the operator's cab.
The use of a pneumatic or hydropneumatic suspension system significantly reduces the vibration load exerted on the operator. The driver's comfort, while operating the machine, is increased significantly. The expected result is a decrease in injuries to the driver's spinal column. There is also reason to expect an increase in productivity as a result of the greater feeling of well being on the part of the operator.
In one embodiment of the invention, the operator's workplace, or the driver's cab, is guided in the vertical direction by guide elements and is supported on one, two or more cylinders filled with one or two fluids. The guide elements used can be either conventional linear guides such as slides, roller guides, circulating ball guides, and dovetail guides or lifting platform guides. If the travel of the cab is not particularly long, guides consisting of leaf springs or movable arms, for example of the type used on sliding lattice grates, can also be used. Guides on levers or connecting rods can also be used, of the type widely used in the design of suspended chassis of motor vehicles. The fluid is initially pressurized by an adjustable-pressure reservoir unit. The initial pressure can be set to the desired level and thereby adjusted to the weight of the driver. The use of a hydropneumatic suspension system also makes it possible to adjust the height of the cab, and is recommended in particular for use on fork lift trucks, because on these vehicles there is generally already a hydraulic pump that provides sufficient hydraulic pressure.
In one embodiment of the invention, there is an adjustable throttle in the fluid line between the cylinder and the reservoir element, in which case the system consisting of the cylinder, reservoir and throttle represents a spring-mass-damper system, in which the stiffness of the spring can be adjusted by the initial pressure in the reservoir unit, and the damping can be modified by adjusting the cross section of the throttle. This spring-mass-damper system can be adapted to the different cab models or to different driver weights by modifying the initial pressure and the cross section of the throttle. The operator's cab can then be moved up and down by several centimeters, for example, and is effectively suspended by the system described above.
In an additional embodiment of the invention, there can be an active regulation of the suspension system. A system of sensors in the machine can record the operating conditions, and a closed-loop control system continuously sets and adjusts the optimal parameters for the suspension system (initial pressure in the reservoir and throttle cross section). This system further increases the quality of the ride in the vehicle during travel and operation.
BRIEF DESCRIPTION OF THE DRAWINGS
Additional advantages and features of the invention are described in greater detail hereinafter, with reference to the exemplary embodiment of the invention which is illustrated in the accompanying three drawings wherein:
FIG. 1 is a schematic view of a portion of the chassis of a fork lift truck showing the operator's station and its suspension system according to the present invention;
FIG. 2 is a schematic view of a hydropneumatic system as shown in FIG. 1; and
FIG. 3 is a partial view of the chassis of a fork lift truck including the suspension system according to the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 is a schematic illustration of a portion of a chassis 2 of a fork lift truck with an operator's cab 4 which contains the driver's seat. An operator's cab 4 of this type is generally in the form of a driver's cab, to protect the driver from falling loads or in the event the vehicle tips over. In this exemplary embodiment, the operator's cab 4 is mounted by guide elements 6 so that its height can be adjusted in relation to the chassis 2 . The weight of the operator's cab 4 is supported by a pneumatic or hydropneumatic spring element 8 , which in this case is located centrally in relation to the operator's cab 4 . This pneumatic or hydropneumatic spring element 8 , therefore, makes it possible to damp vibrations that would otherwise be transmitted undamped to the operator's cab 4 from the frame of the chassis 2 .
FIG. 2 is a more detailed illustration of the spring element 8 of a hydropneumatic suspension system. In this case, the spring element 8 consists essentially of the cylinder 10 , the piston of which supports the operator's cab 4 , a reservoir unit 12 with an adjustable initial pressure and a fluid line between the cylinder 10 and the reservoir element 12 . An adjustable throttle element 14 is provided in this fluid line. Inside the reservoir element 12 there is an elastic membrane, e.g. a rubber membrane, which separates an incompressible fluid such as oil, for example, from a compressible fluid such as air. In this case, the compressible fluid is in the lower half of the reservoir element 12 . The incompressible fluid fills the other half of the reservoir element 12 , the fluid line and part of the cylinder 10 . Impact loads that result from travel over bumps and depressions and are exerted on the chassis 2 are elastically absorbed by the cushion of air in the reservoir element 12 . The piston of the cylinder 10 transmits the impact to the operator's cab 4 only in a greatly damped form.
FIG. 3 shows a chassis 2 of a fork lift truck that is equipped with the suspension system according to the invention. In this case, the chassis 2 contains an electric motor 2 a , an electronic control system 2 b , fastening elements 2 c for the lifting platform and a plurality of batteries 2 d . The invention teaches that there are guide slides 6 a , in this case on each on the left and right sides in the vicinity of the front wheels and a third in the rear center. Engaged with these guide slide elements are the guide rods that are located on the operator's cab 4 and project downward. When the operator's cab 4 is occupied, the height of the cab can be adjusted vertically with respect to the chassis 2 . The spring element 8 is provided to support the load of the cab or of the operator's cab 4 . In this case, the spring element 8 is located directly next to the guide element 6 a and is shown pushed all the way down. When there is an initial pressure provided by the hydraulic fluid, the cylinder in the spring element 8 moves up and thus supports the weight of the occupied operator's cab 4 .
Having described presently preferred embodiments of the invention, it is to be understood that it may be otherwise embodied within the scope of the appended claims.
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A mobile machine, in particular a fork lift truck, having a chassis and a cab located on the chassis. There are one or more pneumatic or hydropneumatic suspension elements to improve comfort and ride quality between the chassis and the cab.
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BACKGROUND OF THE INVENTION
The invention relates to oxy-acetylene and the like gas torches, and in particular to those which have application to the sprayed deposition of metal or other powdered material to form a coating on a substrate. Such torches are exemplified by constructions disclosed in Huhne et al. U.S. Pat. No. 3,986,668.
A torch of the character indicated must be able to apply intense heat to the powder material to be sprayed, and the problem of high-heat delivery for a given size torch increases as higher-temperature materials become available or are specified for incorporation in the powder formulation. Higher heat delivery means greater flows of oxygen and of fuel gas, and thus larger gas-flow passages, with increasing susceptibility to "flash-back", involving shock-wave transmission through the mixed-gas distribution system; and shock-wave incidence at the mixing locale is sufficient to extinguish the torch, thus frustrating the otherwise uniform coating or other function of the torch, and sometimes requiring rejection or costly reworking of the incompletely coated substrate article.
BRIEF SUMMARY OF THE INVENTION
It is an object of the invention to provide an improved torch of the character indicated, avoiding or substantially reducing operational problems of past configurations.
A specific object is to meet the above object via characterizing features of the nozzle construction per se, whereby "flash-back" tendencies can be materially reduced and localized near the region of multiple-jet discharge for establishment of the flame of the torch.
Another specific object is to provide such a nozzle as a simple removable attachment to the gas and powder distributor of a torch assembly.
A general object is to meet the above objects with minimum modification of existing torch structures, with inherent simplicity of construction and ease of servicing, and without undue expense.
The foregoing objects and other features are achieved by the invention as applied to a nozzle construction for removable attachment to the gas and powder distributor of a torch for flame-spraying of powder material, the configuration being such that a flow of powder material is discharged within a surrounding annular locus of torch-flame development. Flash-back tendencies are reduced to relative insignificance by providing within the nozzle first and second successive annular manifold cavities of relatively large sectional area for supply of a flow of combustible-gas mixture to an angularly spaced plurality of discharge-jet passages, there being a circumferentially continuous annular restrictive baffle formation between the two large-area manifold cavities. The dimensional proportions of the manifolds of the baffle restriction and of the discharge-jet passages are important to achievement of the indicated objects.
DETAILED DESCRIPTION
Illustrative embodiments of the invention are shown in the accompanying drawings, in which:
FIG. 1 is a longitudinal sectional view of a gas distributor of a torch, a preferred nozzle of the invention being shown secured to the distributor, and a flame-shaping shroud being mounted to the nozzle;
FIG. 2 is a right-end view of the nozzle of FIG. 1, shown without the shroud of FIG. 1; and
FIG. 3 is a fragmentary view similar to FIG. 1, to show a modified nozzle construction.
In FIG. 1, the invention is shown in application to a gas distributor 10 carrying a detachably secured nozzle 11 of the invention. The gas distributor 10 includes means, such as threads 12 at its upstream end, for attachment to available flame-spraying torch-body structure (not shown) but which will be understood to include its own means for mixing oxygen with fuel gas, such as acetylene, to provide a continuous flow of the same to plural angularly spaced elongate passages 13 in the annular body of distributor 10. At the same time, the torch body will be understood to include provision for suitably controlled carrier-gas entrainment of powder to be sprayed, the flow of carrier gas and powder being independently delivered to the upstream end of a central passage of the distributor 10; such central passage is shown lined with a wear-resistent sleeve-liner insert 14, as of tungsten carbide.
The nozzle 11 is a replaceable insert characterized by first and second cylindrical lands 15-16 having sealed telescopic fit to inner and outer counterbores 17-18 at the downstream end of distributor 10. A first of these seals is provided by an elastomeric O-ring 19 in a peripheral groove in the land 15, thus assuring independence of carrier gas and powder flow, along a straight central course from the distributor liner 14 to the straight central bore 20 of nozzle 11. The second of these seals is provided by a second elastomeric O-ring 21 in a peripheral groove in the land 16, the latter being the outer finish of a shoulder-forming radial flange 22; a flanged nut 23 circumferentially engages the shoulder at flange 22 and removably retains the telescoping fit via threaded engagement to distributor 10, at 24. The land 15 extends beyond land 18 in the upstream direction, so that in insertably assembling nozzle 11 to distributor 10, initial centering contact will be made by the chamfered end of land 15 to a flare or bevel formation 17' at the downstream end of counterbore 17.
The nozzle 11 comprises a cupped generally cylindrical body with a central tubular stem 25 extending in the upstream direction, from the closed end 26 of the body and coaxially within the skirt 27 of the body, to define a relatively large manifold region between the stem 25 and the skirt 27 of the body. And the downstream end of the manifold region communicates with a plurality of elongate cylindrical discharge-jet passages 28, at angularly spaced locations about the nozzle axis. A central tubular extension 29 of passage 20 assures carrier-gas and powder discharge at a location downstream of the base of flame development, at the respective discharge ends of jet passages 28.
In the form of FIG. 1, an annular baffle ring 30 is secured to the outer wall surface of the tubular stem 25, at a location intermediate the longitudinal ends of the inner wall surface of the body skirt 27, thus establishing a succession of communicating first, second, and third annular manifold regions, namely, a substantially restricted but circumferentially continuous manifold region (second annular manifold region) 31 between a substantially larger upstream manifold region (first annular manifold region) 32 and a substantially larger downstream manifold region (third annular manifold region) 33. And by providing in distributor 10 an intermediate counterbore 34 of axial extent Δ, adjacent to and upstream from counterbore 18, a substantially enlarged circumferentially continuous extension of manifold region 32 is established for free and unimpeded combustible-gas supply from passages 13 to the manifold region 32.
For assurance against flash-back in the context of the relatively great flows of combustible-gas mixture contemplated for the described structure, it is important that certain dimensional proportions be observed. Thus, the combined sectional areas of the discharge jets 28 should be less than the sectional area of the restricted (baffled) annular manifold 31, and the latter should be less than the combined sectional areas of the distributor passages 13; by the same token, the sectional area of each of the manifold regions 32-33 should substantially exceed that of the restricted manifold 31. The axial length of all discharge-jet passages 28 should be at least five and preferably about ten times their diameter; and the axial length of the restricted manifold region 31 should be several times its radial span, being shown as preferably three times.
More specifically, for an illustrative case of a torch equipped with a distributor 10 and nozzle 11 and wherein oxy-acetylene mixture provided a maximum 1250 b.t.u. per minute flame discharge, in the circumstance of inert carrier gas and non-exothermic powder, the jet passages 28 were 0.035-inch diameter and 0.375-inch length. The restrictive radial gap at 31 was 0.031 inch to a skirt 27 having a bore diameter of 0.60 inch, the length of gap 31 being 0.094 inch. And the distributor passages were six in number, and of 0.094 inch diameter. The combined sectional area at 28 was thus 14 times 0.0243 in 2 , i.e., 0.340 in 2 ; the restrictive area at 31 was 0.026 in 2 , and the combined sectional area at 13 was 0.040 in 2 ; thus importantly, the restrictive area at 31 is close to but greater than the combined sectional area of discharge at 28, but the area at 31 is substantially less than the combined feed area at 13. A smooth flame of the indicated heat output is developed, free of flash-back, and even in the circumstance of carrier gas and/or powder material contributing to the heat development, there were no disabling flash-backs.
It will be seen that the described structure meets all stated objects. The nozzle 11 per se is structurally simple, effective in performance, and easily removed and installed.
While the invention has been described for the preferred forms of FIGS. 1 and 2, it will be understood that modifications may be made without departure from the scope of the invention. For example, detachable annular shroud subassembly 35 may be telescopically fitted to the downstream end of nozzle 11, being shown in partial overlap with an elongate hub portion 36 of nut 23, for attachment by set-screw means 38. The subassembly 35 is characterized by an annular manifold cavity 37 serving a plurality of inwardly canted discharge jets 39, for directional discharge of flows of air, inert gas or oxygen, provided by independent supply via passage means 40. When such jets 39 are sufficiently close and in sufficient number, they achieve a gas shroud around the flame spray, serving to accelerate the same; and two such jets 39, at diametrically opposite locations will produce a flame-flattening effect upon the discharge of flame and powder, thus enabling the user to apply the flame spray as a ribbon. Other flame-shaping configurations are disclosed in my copending patent application, Ser. No. 131,199, filed Mar. 17, 1980.
Still further, although the form of FIGS. 1 and 2 has been said to be preferred, it is possible to achieve the indicated baffle effect by forming the restrictive gap 31' (between manifolds 32'-33') along the outer-wall surface of stem 25, as shown specifically in FIG. 3. However, it will be appreciated that to achieve the same sectional area for restrictive gap 31' (FIG. 3) as for gap 31 (FIG. 1), all other conditions being the same, the gap 31' will necessarily be of greater radial extent than the gap 31, due to the shorter radius at which gap 31' is located.
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The invention contemplates improved nozzle structure removably securable to a gas-distributor body for delivering and discharging independent flows of combustible-gas mixture and of powder material to be flame-sprayed by a gas torch to which the nozzle is fitted. The combustible-gas mixture is successively accommodated in annular manifold regions of relatively large sectional area, respectively upstream and downstream from an intermediate annular manifold region of relatively restricted sectional area, for inhibiting flash-back to the gas distributor and for effectively limiting any flash-back effects to the manifold region downstream of the annular restriction.
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CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This is a continuation-in-part application of pending international application PCT/EP2014/054493 filed Mar. 7. 2014, and claiming the priority of German application No. 10 2013 102 898.5 filed Mar. 21, 2013. The said International application PCT/EP2014/054493 and German application No. 10 2013 102 898.5 are both incorporated herein by reference in their entireties as though fully set forth.
BACKGROUND OF THE INVENTION
[0002] The invention relates to an ironing ring for use in a press for ironing pressing of a workpiece.
[0003] Such ironing rings have been known per se. In a press for ironing pressing or drawing a workpiece, for example a cup, several such ironing rings are successively arranged, as a rule, in the direction of the working stroke in order to intermittently or incrementally reduce the outside diameter of the workpiece. As a result of this, it is possible, for example, to ultimately form a hollow cylindrical can body from a cup.
[0004] During the deforming process, a radially inward facing work surface of the ironing ring comes into contact with the workpiece. Depending on the material of the workpiece, more or less viscous, smeary material build-up or friction deposits occurs. This phenomenon is known. Nowadays, the ironing rings are therefore deinstalled from the press after a certain number of deforming processes, cleaned and subsequently reinstalled. This is labor-intensive and expensive and has caused the shutdown of the press.
[0005] In order to avoid friction deposits, publication DE 22 56 334 A1 discloses the possibility of applying a special lubricant to the ironing ring or the workpiece. However, such lubricants must subsequently be removed again from the deformed workpiece. This option is labor-intensive and expensive as well. Publication DE 22 56 334 A1 suggests that the ironing ring be made of ceramic material. However, if pressure is suddenly removed from the ceramic ironing ring, fissures may form, this being prevented according to DE 22 56 334 A1 in that the end region of the workpiece may immerse into a recess on the ironing stamp in order to avoid the sudden removal of pressure from the ceramic ironing ring.
[0006] Considering this, the object of the present invention may be viewed to be an ironing ring in which the risk of friction deposits is reduced and which does not require any design changes on other press components.
SUMMARY OF THE INVENTION
[0007] The invention provides an ironing ring 10 for use in a press for ironing pressing or drawing of a workpiece 11 . The ironing ring 10 has a work surface 15 which, upon deforming the workpiece 11 , contacts the workpiece 11 and causes flowing of the workpiece material. In order to prevent friction deposits (friction deposits) in the region of the work surface 15 of the ironing ring 10 , a microstructure 22 , differing from the roughness of the work surface, is introduced into the work surface 15 , which forms elevations 23 and/or recesses 24 in the work surface 15 . Material particles remaining on the work surface 15 after the deforming of a workpiece 11 thus adhere less strongly to the work surface 15 and can be stripped off during the next deforming process.
[0008] On its inside, the ironing ring has an interior work surface that comes into contact with the workpiece when the workpiece is being deformed. As a rule, the part of the ironing ring comprising the work surface or the entire ironing ring is made of a metallic material, in particular hard metal or tool steel. In particular on its work surface, the ironing ring is not provided with a coating and can be used without the use of lubricants. In accordance with the invention, the work surface is provided with a microstructure that includes elevations and/or recesses. These elevations and/or recesses form an uneven microstructure in the nanometer-range or micrometer range. The result of the microstructure is that, during a deforming process, particles of the deformed workpiece remaining on the work surface of the ironing ring adhere less strongly and can thus be removed easily, for example, they can be stripped off during one of the subsequent deforming processes. As a result of this, the risk of friction deposits is at least greatly reduced. In this manner, it is possible to avoid cleaning of the ironing ring or to at least drastically reduce the number of cleaning processes.
[0009] The microstructure is a form design of the work surface that is formed independently of and in addition to the roughness of the work surface. The microstructure of the work surface is directly introduced in the metallic material, in particular hard metal or tool steel, of the ironing ring. Therefore, additional coatings are not necessary. Metallic materials that are standard in ironing rings may be used. The microstructure can be produced by the defined ablation of material, for example by laser ablation.
[0010] In a few exemplary embodiments, the elevations and/or recesses of the microstructure have a regular pattern, for example due to the uniform arrangement of the elevations and/or recesses along the work surface. However, it is also possible to provide irregular microstructures, for example by varying the form, size and arrangement of elevations and/or recesses which may take place stochastically or consistent with a prespecified rule of arithmetic. A combination of regular and irregular sections or regions of the microstructure is also possible.
[0011] With a regular pattern of the microstructure, the center axes or center planes or maxima of adjacent elevations of the microstructure are preferably at the same distance. The contour of the elevations as well as the distance between the center axes or center planes or maxima, of two adjacent elevations can be defined as a function of the material of the workpiece that is to be deformed. For example, elevations may have a spherical, cylindrical or conical contour, or they may have the contour of a truncated cone, a pyramid, a truncated pyramid, a parallelepiped or a cube. Recesses of the microstructure form an intermediate space between these elevations.
[0012] Alternatively or in addition to elevations rising in the direction of the normal vector on the work surface of the ironing ring, there may also be recesses. The distance of the center axes or center planes or minima of respectively adjacent recesses of the microstructure may be the same, so that also in this case a uniformity in the microstructure is achieved.
[0013] The distance between the center axes or center planes or minima or maxima of adjacent elevations or adjacent recesses is preferably less than 50 micrometers. Depending on the material of the workpiece that is to be deformed, this distance may also be less than 1000 nanometers. Preferably, this distance is greater than 50 nanometers.
[0014] The microstructure may be embodied as a 3-dimensional or a 2.5-dimensional structure. If a three-dimensional microstructure is intended, the maximum height difference between the maxima of the elevations and the minima of the recesses measured in the direction of the normal vector on the work surface is at most 500 nanometers.
[0015] In one embodiment of the invention the elevations of the microstructure taper in the direction of the normal vector of the work surface. Therefore, the elevations have lateral flanks that are inclined relative to the normal vector on the work surface. The recess or the distance between two elevations thus increases toward the maximum or toward the free end of the elevation. As a result of this, an additional reduction of the adhesion of particles can be achieved.
[0016] An elevation and/or a recess of the microstructure, preferably measured transversely to the extension direction of the normal vector, may have in one or more dimensions a transverse dimension that is smaller than 10 micrometer and, in particular smaller than 1000 nanometers.
[0017] Preferably, the work surface has two surface sections that subtend an angle. The two surface sections are inclined relative to the longitudinal axis of the ironing ring. An ironing edge may exist in the transition region between the two surface section.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] Advantageous embodiments of the ironing ring can be inferred from the dependent claims as well as the description. The description is restricted to essential features of the invention. The drawings are to be used for supplementary reference. Hereinafter, exemplary embodiments of the invention are explained in detail with reference to the appended drawings. They show in:
[0019] FIG. 1 a schematic representation of an ironing ring, an ironing stamp, as well as of a workpiece, in a sectional view along the longitudinal axis of the ironing ring;
[0020] FIG. 2 a schematic sectional view of the ironing ring according to FIG. 1 , along the longitudinal axis of the ironing ring; and,
[0021] FIGS. 3 to 12 show a schematic diagram of elevations and/or recesses of the microstructure of the work surface of the ironing ring.
DETAILED DESCRIPTION OF THE INVENTION
[0022] FIGS. 1 and 2 show, greatly schematized, an ironing ring 10 for ironing a workpiece 11 , i.e., a cup in accordance with the example, wherein the workpiece 11 is moved with the aid of a stamp 12 through the ironing ring 10 . The ironing ring 10 is supported by a ring holder 13 in a die 14 of a press that is not specifically shown in detail. By means of the press drive of the press, the stamp 12 with the workpiece 11 is pressed for deformation through the ironing ring 10 . In doing so, the workpiece 11 comes into contact with a radially interior work surface 15 of the ironing ring and is thus deformed. Referring to the exemplary embodiment, the wall thickness of the workpiece 11 , i.e., a cup is reduced as a result of this, whereby the length of the cup increases. Usually, considering presses for ironing drawing or ironing pressing of a workpiece 11 in a die 14 , there are several ironing rings 10 arranged at distance from each other, as a result of which the deformation of the workpiece 11 takes place intermittently or incrementally.
[0023] In the exemplary embodiment, the ironing ring 10 consists of metal and, in particular, of hard metal or tool steel. About its longitudinal axis L, this ring is completely closed. The work surface 15 is arranged on the interior surface 16 of the ironing ring 10 facing the longitudinal axis L. In doing so, the work surface 15 may be a component of the interior surface 16 or be formed by the entire interior surface 16 . In the exemplary embodiment, the work surface 15 has a first surface section 15 a and a second surface section 15 b. Both surface sections 15 a, 15 b are inclined relative to the longitudinal axis L and have the form of the circumferential surface of a truncated cone. At the location of transition between the two surface sections 15 a, 15 b there is formed an ironing edge 17 that, in modification of the schematic drawings of FIGS. 1 and 2 , may also be provided with a radius. The diameter of the work surface 15 is the smallest at the ironing edge, in which case the diameter increases in the direction of the longitudinal axis L in both directions.
[0024] When ironing the workpiece 11 , the work surface 15 comes into contact with the workpiece 11 . Due to the friction and the pressure between the workpiece 11 and the work surface 15 it may happen that particles of the workpiece material cling to the ironing ring 11 and adhere there due to the action of the pressure between the workpiece 11 and the ironing ring 10 . This process is also referred to as friction deposits. These material adhesions to the ironing ring 10 cause the form to change in the region of the work surface 15 and to thus no longer result in the desired deformation of the workpiece 11 . Therefore, until now, the ironing ring 10 must be deinstalled and cleaned after a certain number of deforming processes. During this time, the press is stopped.
[0025] According to the invention such friction deposits during deformation is avoided or at least reduced. This is accomplished in that the work surface 15 and/or the entire interior surface 16 of the ironing ring 10 are provided with a microstructure 22 that is shown highly schematized in dotted lines in FIG. 2 . In modification of the illustration as in FIG. 2 , the microstructure 22 can also be provided on the entire interior surface 16 . The microstructure 22 is directly formed in the material of the ironing ring 10 . The ironing ring 10 is not provided with a coating in the region of the work surface 15 and, in particular, in the region of the entire interior surface 16 . In the exemplary embodiment, the ironing ring 10 is completely made of a uniform metal material.
[0026] The microstructure 22 has elevations 23 and/or recesses 24 , as a result of which a regular pattern of elevations 23 and thus of interspaced recesses 24 is formed in the work surface 15 of the ironing ring 10 in accordance with the example. Alternatively, it would also be possible to distribute the elevations 23 and/or the recesses 24 irregularly and, for example, stochastically, within the work surface 15 , which is only shown in an exemplary manner in the schematic of FIG. 12 . The microstructure 22 has the form design of the work surface 15 that is created independently of or in addition to the roughness of the work surface 15 .
[0027] FIGS. 3 to 12 schematically illustrate different forms and/or exemplary embodiments of elevations 23 to produce a microstructure 22 . It is also possible to use the contours or forms of these elevations 23 for the recesses 24 and, as it were, provide recesses complementary to the elevations and thus obtain a microstructure 22 . Likewise, a combination of such recesses with the depicted elevations 23 is possible.
[0028] Transversely to the normal vector N relative to the work surface 15 or a surface section 15 a, 15 b of the work surface 15 , the elevations 23 and/or recesses 24 have at least one dimension of a transverse measurement Q that, in accordance with the example, is less than 20 micrometers and, in particular, less than 1000 nanometers. In the respectively other dimension transversely to the normal vector N, the dimension of the elevation 23 or the recess 24 can be greater, in which case these may be, in particular, also so-called linear elevations 23 and recesses 24 that are configured so as be closed in a ring form around the longitudinal axis L or may end at the ends of the work surface 15 —viewed in the direction of the longitudinal axis L. Such examples of linear elevations or recesses are schematically illustrated in cross-section by FIGS. 8 to 11 .
[0029] Due to the microstructure 22 , it is possible to avoid or at least reduce friction deposits on the work surface 15 of the ironing ring 10 . When the workpiece 11 is being deformed it may happen that particles of the workpiece material remain clinging to the work surface 15 of the ironing ring 10 . Due to the microstructure 22 , the contact surface between such particles and the work surface 15 is reduced. Consequently, adhesion is decreased. The result of this is that, during the next deforming process, such particles located on the work surface 15 can be readily stripped off, thus clearly reducing the risk of friction deposits.
[0030] Depending on the concrete deforming task, the design and dimensioning of the microstructure 22 may vary. For example, the form and dimensioning of elevations 23 and recesses 25 is dependent on the material of which the workpiece 11 is made. In doing so, in particular the pairing of materials between the material of the ironing ring 10 and the material of the workpiece 11 must be taken into account. When cups are being ironed for the deformation of can bodies, aluminum or tinplate are frequently used, the latter also being potentially coated with plastic material, depending on the purpose of use of the can.
[0031] It is thus possible to vary the design and dimensioning of the irregularities 23 , 24 of the microstructure 22 . The use of linear elevations 23 or recesses 24 ( FIGS. 8 to 11 ) as well as the use of bump-like elevations 23 or recesses 24 is possible. FIGS. 3 to 7 illustrate—only as examples—a few designs of bump-like elevations 23 , between which grid-like, linear recesses 24 are provided, said recesses separating the individual elevations 23 from each other.
[0032] In the exemplary embodiment, the maximum height difference H between the maxima S or peaks of the elevations 23 and the minima G or the bottom of the recesses 24 is less than 500 nanometers. The height difference H is measured in the direction of the normal vector N on the work surface 15 or the respective work surface section 15 a, 15 b.
[0033] FIGS. 3 to 7 show, highly schematized, different exemplary embodiments of microstructures 22 . In these exemplary embodiments, the individual elevations 23 are separated from each other by linear, groove-like recesses 24 . The elevations 23 may have the form of parallelepipeds or cubes ( FIG. 3 ), the form of a cylinder ( FIG. 4 ), the form of a truncated cone ( FIG. 5 ), be ring-shaped ( FIG. 6 ) or have the form of a pyramid or tetrahedron ( FIG. 7 ). Other forms such as, for example, honeycomb-shaped elevations 23 or spherical elevations 23 can also be used. These mentioned embodiments are only exemplary. There exists a multitude of possibilities of configuring the elevations 23 . Important is that the support surface or contact surface between the material of the workpiece 11 and the ironing ring 10 is reduced, thus reducing the adhesion between a material particle of the workpiece material and the work surface 15 .
[0034] The elevations 23 may by rotation-symmetrical about their respective longitudinal center axis M ( FIGS. 4 to 6 ). They may also taper toward their free end, this being illustrated, for example, by the form of a truncated cone in FIG. 5 and by the form of a pyramid in FIG. 7 . Instead of the pyramid or tetrahedron form in FIG. 7 , it would thus be possible to provide, for example, elevations 23 having the form of a truncated pyramid or a truncated tetrahedron. Considering such embodiments of the elevations 23 , flanks 25 being inclined relative to the center axis M are formed. The angle of inclination a measured between such a flank 25 and the center axis M or a parallel line relative to the center axis M may be in the range of 110° to 160°.
[0035] In accordance with the example, the distance between two elevations 23 is defined between the center axes M and the center planes E, respectively, of two adjacent elevations 23 . Accordingly, the distance A between two adjacent recesses 24 is defined as the distance A between their center axes M and their center planes E, respectively. If, based on the form, a center axis M or a center plane E cannot be determined at an elevation 23 or a recess 24 , the distance A between two adjacent elevations 23 or two adjacent recesses 24 between the maxima S of the adjacent elevations 23 or the minima G between adjacent recesses 24 can be measured. In the case of irregular microstructures 22 , it is also possible—as illustrated in an exemplary manner by FIG. 12 —to determine the distance A between the centroids of the elevations 23 . Accordingly, this distance determination can also be used with adjacent recesses 24 .
[0036] In the exemplary embodiment, the distance A determined in one of the mentioned ways between two adjacent elevations 23 or two adjacent recesses 24 is less than 50 micrometers and, preferably, less than 1000 nanometers. Preferably, this distance A is greater than 50 nanometers.
[0037] Such microstructures 22 in the nanometer range or the micrometer range can be generated on the work surface 15 by laser ablation. For example, several laser beams may be interferometrically superimposed in order to produce the desired structures on the work surface 15 .
[0038] In regular microstructures 22 , the distance A between two adjacent recesses 24 or two adjacent elevations 23 is constant. As a result of this, a regular, uniform pattern of the microstructure 22 along the entire work surface 15 is achieved. It is also possible to provide different microstructures 22 in different sections or regions of the work surface 15 . For example, it is possible to provide a different microstructure 22 in the region of the first surface section 15 a than in the second surface section 15 b.
[0039] FIGS. 8 to 11 show elevations 23 and recesses 24 that, in accordance with the example, extend closed in the form of a ring around the longitudinal axis L, so that ring-shaped elevations 23 or ring-shaped recesses 24 are formed. As illustrated schematically and in an exemplary manner by FIGS. 8 and 9 , the elevations 23 or recesses 24 need not be symmetrical with respect to a radial plane relative to the longitudinal axis L. Starting at a maximum S of an elevation 23 , for example, the steepness of the flanks may be different in the opposite direction. Viewed in the direction of movement of the workpiece 11 through the ironing ring 10 , the workpiece is only or mainly in contact with the flatter flanks 25 a increasing to the maximum S, as is schematically illustrated by FIGS. 8 and 9 . A sawtooth-shaped microstructure 22 , as it were, can be achieved, wherein the edges in the region of the maxima S of the elevations and/or in the region of the minima G of the recesses can be embodied so as to have a sharp edge or be rounded.
[0040] According to FIG. 10 , the elevations 23 have a bump-like cross-section and thus form annular ribs. All previously described contours for the elevations 23 can also form—as a negative profile—recesses 24 in the work surface 15 or in the respective surface section 15 a, 15 b. FIG. 11 illustrates an example of this. Instead of the ring-shaped rib-like elevations 23 ( FIG. 10 ), it is also possible to form ring-shaped recesses 24 having the appropriate cross-sectional contour.
[0041] In modification of the representations of FIGS. 3 to 11 , the center axes M or center plane E need not have the same orientation as the normal vector N of the respective surface sections 15 a, 15 b or the work surface 15 .
[0042] The contours of the elevations 23 and recesses 24 described in conjunction with FIGS. 3 to 11 may also be used in any desired combination. Inasmuch as the distance of the work surface 15 from the longitudinal axis L is not consistent due to the inclination of the surface sections 15 a, 15 b, the pressure between the workpiece 11 and the work surface 15 increases as the distance of the work surface 15 from the longitudinal axis L decreases. Therefore, it may be advantageous to configure the microstructure 22 in regions of higher pressure differently from regions of lower pressure.
LIST OF REFERENCE SIGNS
[0043] 10 Ironing ring
[0044] 11 Workpiece
[0045] 12 Stamp
[0046] 13 Ring holder
[0047] 14 Die
[0048] 15 Work surface
[0049] 15 a First surface section
[0050] 15 b Second surface section
[0051] 16 Interior surface
[0052] 17 Ironing edge
[0053] 22 Microstructure
[0054] 23 Elevation
[0055] 24 Recess
[0056] 25 Flank
[0057] 25 a Flank with a smaller inclination
[0058] A Distance
[0059] G Minimum
[0060] E Center plane
[0061] H Height difference
[0062] L Longitudinal axis
[0063] M Center axis
[0064] N Normal vector
[0065] Q Transverse dimension
[0066] S Maximum
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An ironing ring for use in a press for ironing pressing or drawing of a workpiece. The ironing ring has a work surface which, upon deforming the workpiece, contacts the workpiece, and causes flowing of the workpiece material. In order to prevent friction deposits in the region of the work surface of the ironing ring, a microstructure, differing from the roughness of the work surface, is introduced into the work surface, which forms elevations and/or recesses in the work surface. Material particles remaining on the work surface after the deforming of a workpiece thus adhere less strongly to the work surface and can be stripped off during the next deforming process.
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RELATED APPLICATIONS
[0001] This patent application makes reference to, claims priority to and claims benefit from Chinese Patent Application No. 200710119205.1 filed on Jul. 18, 2007. The disclosure of this Chinese Patent Application is incorporated herein by reference in its entirety.
FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] [Not Applicable]
MICROFICHE/COPYRIGHT REFERENCE
[0003] [Not Applicable]
BACKGROUND OF THE INVENTION
[0004] The presently described technology relates to a low-nickel austenitic stainless steel and method for producing same. More particularly, this invention relates to an austenitic stainless steel retaining excellent mechanical properties and corrosion resistance with low-nickel level, and method for producing the same.
[0005] In recent years, the commercially available stainless steels are mainly 300 series and 200 series between which there is a difference in the level of element nickel that results in an obvious difference in their properties and cost.
[0006] The 300 series is known as chromium-nickel stainless steel, of which the typical steel grade is 304 stainless steel characterized by the basic composition of 18Cr-8Ni. The 200 series is known as chromium-manganese stainless steel, of which the typical steel grade is 201 stainless steel characterized by the basic composition of 17Cr-5Ni-7Mn. The 200 series is also known as nickel-saving stainless steel, in which a part of nickel is replaced by manganese. Although the 200 series is low-priced, they have decreased corrosion resistance, improved tensile strength and elevated cold work hardening rate as compared to the 300 series, which result in elevated cost of casting's cold working.
[0007] Nickel resource is so rare that it exists naturally only in about 15 countries in the world. It is, therefore, necessary to develop an austenitic stainless steel having sufficient properties and decreased nickel content, so as to save nickel, reduce casting production cost and improve commercial competitiveness.
[0008] For this reason, a low-nickel austenitic stainless steel STC204Cu based on chromium-manganese stainless steel 201 has been developed by the inventors and used in investment casting, in order to improve corrosion resistance and cold work formability of Alloy 201.
BRIEF SUMMARY OF THE INVENTION
[0009] One object of the presently described technology is to provide an economical and low-nickel austenitic stainless steel with excellent mechanical properties and corrosion resistance.
[0010] Another object of the presently described technology is to provide a method for producing the low-nickel austenitic stainless steel.
[0011] The low-nickel austenitic stainless steel of the invention (referred to as “STC204Cu” hereafter) comprising by weight:
[0000]
C
≦about 0.08%
Mn
about 4.0~5.0%
Si
about 0.7~1.0%
Ni
about 3.5~4.5%
Cr
about 16.0~18.0%
Cu
about 3.0~3.50%
S
≦about 0.045%
P
≦about 0.030%
total amount of impurity elements
≦about 0.2%
Fe
balance.
[0012] In a preferred embodiment of the invention, the composition of STC204Cu is as follows:
[0000]
C
≦about 0.06%
Mn
about 4.0~4.5%
Si
about 0.7~1.0%
Ni
about 4.0~4.2%
Cr
about 17~17.5%
Cu
about 3.0~3.2%
S
≦about 0.045%
P
≦about 0.030%
total amount of impurity elements
≦about 0.2%
Fe
balance.
[0013] In accordance with one embodiment of the presently described technology, the method for producing the stainless steel STC204Cu comprises steps of: providing metallic raw materials (charge calculation), smelting the metallic raw materials in an electric furnace to form a composition, on-the-spot sample analyzing composition, adjusting the composition according to the analysis result, regulating the temperature of the composition, pouring the composition, and heat-treating the composition.
Advantageous Effects
[0014] The low-nickel austenitic stainless steel STC204Cu in accordance with at least one embodiment of the presently described technology has a reduced nickel level, lower material cost, corresponding work hardening behavior and processing cost as compared to usual stainless steel 304. After being heat treated, the STC204Cu in accordance with at least one embodiment of the presently described technology has improved strength and corresponding corrosion resistance while cost is lower as compared to stainless steel 304.
[0015] Expensive stainless steel 304 may be replaced by STC204Cu in the applications for architectural hardware, household goods, cookware and hardware for bath, such as glass wall claws, handles of window and door, handles of window or door lock, chaining, fastener, handles of tableware etc., and metallic harness, for example stirrup, bit, spur and the like in general operating environment (not more than 400° C. of operating temperature, medium corrosion environment and below).
BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS
[0016] [Not Applicable]
DETAILED DESCRIPTION OF THE INVENTION
[0017] Based on the composition of stainless steel 201, copper is added to avoid the trouble of cold working on conventional chromium-manganese stainless steel, furthermore, carbon level is decreased and the proportion among silicon, manganese, chromium, nickel and carbon is adjusted so as to improve corrosion resistance and weldability of the alloy.
[0018] In accordance with some embodiments, the composition of low-nickel austenitic stainless steel STC204Cu of the present technology comprises by weight:
[0000]
C
≦about 0.08%
Mn
about 4.0~5.0%
Si
about 0.7~1.0%
Ni
about 3.5~4.5%
Cr
about 16.0~18.0%
Cu
about 3.0~3.50%
S
≦about 0.045%
P
≦about 0.030%
total amount of impurity elements
≦about 0.2%
Fe
balance.
[0019] In some preferred embodiments of the presently describe technology, the composition of STC204Cu is as follows:
[0000]
C
≦about 0.06%
Mn
about 4.0~4.5%
Si
about 0.7~1.0%
Ni
about 4.0~4.2%
Cr
about 17~17.5%
Cu
about 3.0~3.2%
S
≦about 0.045%
P
≦about 0.030%
total amount of impurity elements
≦about 0.2%
Fe
balance.
[0020] A comparison of the compositions of STC204Cu of the present technology, stainless steel 201 and 304 are listed in table 1 below.
[0000]
TABLE 1
Comparison of Compositions
Chemical analysis wt. %
Material
C
Mn
Si
Ni
Cr
Cu
S
P
Fe
STC204Cu
≦0.08
4.0~5.0
0.7~1.0
3.5~4.5
16.0~18.0
3.0~3.5
≦0.045
≦0.030
balance
201 (ASTM)
≦0.15
5.5~7.5
≦1.0
3.5~5.5
16.0~18.0
≦0.060
≦0.030
balance
304 (ASTM)
≦0.08
2.0
1.0
8.0~10.0
18.0~21.0
≦0.045
≦0.030
balance
[0021] In providing metallic raw materials, the use of stainless steel 430 scrap having low carbon content can be helpful for achieving object of the presently described technology. Otherwise, more expensive pure iron, for example, needs to be added to adjust the proportion frequently with increased cost. The amounts of starting materials can be calculated on the basis of the constituent proportion of the low-nickel austenitic stainless steel of the presently described technology.
[0022] During the smelting in an electric furnace, in accordance with one embodiment, the charge is fed in proper order of 430 stainless steel scrap, nickel block and electrolytic manganese; and ferrochrome and copper are fed into the furnace after the charge has been melt. The molten steel is subject to deoxidation after intense stirring, and then the composition and temperature are regulated for pouring.
[0023] During the smelting, in accordance with one embodiment of the present technology, skimming and deoxidizing are important to achieve required molten steel and unique corrosion resistance of castings. The temperatures of deoxidizing and pouring are determined on the basis of the shape and size of castings. It is normal that deoxidizing and standing are carried out at higher temperature while pouring is carried out at lower temperature.
[0024] In accordance with some embodiments of the present technology, the heat-treatment procedure of castings can be critical for excellent combined properties, and especially, the tempering after solution treatment can be important to achieve mechanical property balance and excellent corrosion resistance. The temperature scope of high temperature tempering can be about 500-650° C. In accordance with at least one embodiment, the higher is the temperature for tempering, the better is ductility, and excellent mechanical properties can be retained while corrosion resistance is decreased in some degree (for example, endurance time decreased to 37 hr in 5% salt-fog test box at 96° C.). The process condition for heat treatment should be determined appropriately depending on the desired properties of work piece.
EXAMPLE 1
[0025] Starting metal materials were provided which had the composition of sample 001-1 shown in Table 2. The starting materials in desired proportion were charged into a smelting furnace in the sequence of: scrap of 430 steel, nickel block and electrolytic manganese. After the charge had been melt, ferrochrome and copper were added in. The molten steel was mixed at 180˜220 KW power, and covered with deslagging agent after melting had been finished. The slag was raked off for the first time when the furnace temperature was raised to 1620° C. Sample analysis was carried out on the spot, and then the melt was covered with deslagging agent again. When the temperature reached about 1680° C. to about 1700° C., the melt was subject to skimming and deoxidizing at high temperature, then skimming throughout. If the composition did not need to be adjusted, the melt was covered with deslagging agent and then power supply was cut off in order to regulate temperature. If the composition should be adjusted, the proper alloying agents were added into the furnace, and then the melt was covered with deslagging agent and power supply was cut off in order to adjust the temperature.
[0026] During the period of power-off, slag was raked off for three or four times until all slag had been removed. The molten steel was poured as soon as the desired pouring temperature had been reached.
[0027] The casting was subject to heat treatment after residual mould had been removed from it. The mechanical strength and corrosion resistance measurements of the castings are listed in Tables 3 and 4, respectively, from which it is can be seen that the castings made of the low-nickel stainless steel of presently described technology have improved mechanical strength, corresponding corrosion resistance, decreased nickel level and reduced production cost as compared to stainless steel 304.
EXAMPLE 2˜6
[0028] Stainless steels were produced in the same manner as Example 1, except they had different compositions (002-1, 003-1, 001-2, 002-2, 003-2) as listed in Table 2 below, and were produced at different heat-treatment conditions. The heat treatment procedure for sample 001-1 (Example 1), 002-1 (Example 2) and 003-1 (Example 3) was solution treatment followed by tempering at 570° C., while the heat treatment procedure for sample 001-2, 002-2 and 003-2 (Examples 4-6) was solution treatment followed by tempering at 620° C.
[0029] The chemical analysis listed in Table 2 are the measurements by means of a high-speed spectrum analyzer (HILGGER ANALYTICAL, made in France).
[0000]
TABLE 2
Comparison of Compositions between the Samples of the
Invention and the Stainless Steel 304
Chemical Analysis wt. %
Sample
impurity
No.
C
Mn
Si
Ni
Cr
Cu
S
P
elements
Fe
001-1
0.058
4.8
0.9
4.2
17.6
3.1
0.032
0.025
0.15
balance
002-1
0.052
4.6
0.82
4.3
18
3.25
0.030
0.023
0.17
balance
003-1
0.072
4.5
1.0
4.05
17.1
3.0
0.035
0.022
0.16
balance
001-2
0.058
4.8
0.9
4.2
17.6
3.1
0.032
0.025
0.15
balance
002-2
0.052
4.6
0.82
4.3
18
3.25
0.030
0.023
0.17
balance
003-2
0.072
4.5
1.0
4.05
17.1
3.0
0.035
0.022
0.16
balance
304
≦0.08
2.0
1.0
8.0~10.0
18.0~21.0
none
≦0.045
≦0.030
balance
(1) Mechanical Properties
[0030] All samples, which were smelted, poured and heat treated in the same furnaces as described in Example 1, were tested by means of a tensile tester (TF-212B tensile-and-compression-testing machine, Tuo Feng Instrument Co. Ltd., Shanghai, China) and a hardness tester (TH310 Hardness Tester, Beijing, China). The rounded results are listed in Table 3.
[0000]
TABLE 3
Comparison of Mechanical Properties between the Samples of
the Invention and the Stainless Steel 304
Ductility
Hardness
Material
Yield Strength
Tensile Strength
(%)
(HB)
001-1
310
705
56
200
002-1
305
700
58
198
003-1
325
720
55
210
001-2
310
710
58
199
002-2
307
704
60
196
003-2
330
720
58
206
STC204Cu
≧300
MPa
≧700
MPa
≧55
≦210
304
260
MPa
645
MPa
60
≦180
(2) Corrosion Resistance
[0031] Three (3) sets of castings were tested on the corrosion resistance using the same corrosion testing method. The heat-treated states and compositions of six (6) samples of three (3) sets of castings were shown in Table 2, wherein the chemical compositions were measured by a high-speed spectrum analyzer (HILGGER ANALYTICAL, France). The salt-fog test was carried out for 48 hours in 5% salt-fog at temperature of 96° C. The result data on the corrosion resistance were compared between these 6 samples of the present invention and stainless steel 304. The results are shown in Table 4.
[0000]
TABLE 4
Corrosion Test Results of the Samples of the Invention and the
Stainless Steel 304
Comparative
Sample No.
Corrosion Time (hr)
Results
Sample 304
001-1
48
no corrosion
no corrosion
002-1
48
no corrosion
no corrosion
003-1
48
no corrosion
no corrosion
001-2
48
no corrosion
no corrosion
002-2
48
no corrosion
no corrosion
003-2
48
little pitting corrosion
no corrosion
[0032] It is known from the results that the stainless steel samples of the invention are not corroded after keeping in 5% salt-fog test box at 96° C. for 48 hours, that is, the alloy of the invention and alloy 304 have the corresponding corrosion resistance.
(3) Economic Analysis
[0033] Nickel is one very expensive rare metal. Nickel level of the nickel-saving stainless steel STC204Cu of the present technology is merely half of alloy 304 so that the material cost of STC204Cu is lower than alloy 304 (about 70% of alloy 304 cost), and its expense for casting is about 80% of alloy 304. Furthermore, STC204Cu alloy can be produced in enormous quantities, without modifications of existing equipments.
[0034] In the production of 150t/a tableware's handles, for example, the replacement of usual stainless steel 304 by nickel-saving stainless steel STC204Cu of the present technology would reduce 15% production cost, i.e. about ¥1,665,000 per year.
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A low-nickel austenitic stainless steel is provided which comprises by weight: ≦0.08% C, 4.0˜5.0% Mn, 0.7˜1.0% Si, 3.5˜4.5% Ni, 16.0˜18.0% Cr, 3.0˜3.50% Cu, ≦0.045% S, ≦0.030% P, impurity elements in the total amount of ≦0.2%, and Fe as the balance. This low-nickel austenitic stainless steel has decreased nickel content, but retains excellent mechanical properties and corrosion resistance property. Therefore, the cost for producing the stainless steel can be reduced remarkably. The method for producing the low-nickel austenitic stainless steel is also provided.
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CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of, priority to, and is a non-provisional application of U.S. Provisional Application No. 62/110,357, entitled “SOFTWARE LICENSE RATIO MONITORING AND LICENSE REUSE OPTIMIZATION,” filed Jan. 30, 2015, the contents of which incorporated herein by reference in their entirety for all purposes.
TECHNICAL FIELD
[0002] Various of the present embodiments relate to software/firmware/hardware systems for managing license deployments.
BACKGROUND
[0003] The software ecosystem has developed a myriad of different licensing and implementation environments. Some licensors impose detailed restrictions on their licensees' behavior, limiting the relationships between different active software licenses used by the licensee. Given the diversity of businesses which license such software, businesses are rarely able to comply with such licenses in an optimal manner. Resources are often unavailable, low priority tasks receive excessive access while high priority tasks are underserved, users accustomed to one level of availability find themselves subject to various inconveniences, etc. Additionally, licensees may have differently sized user bases and may employ the software for very different tasks. Thus, a benign restriction in one licensee's context may impose an onerous burden for another licensee.
[0004] Accordingly, there is a need for more effective compliance monitoring and enforcement systems. These systems must be strict enough to honor the required licensing terms, but flexible enough to adapt to the particular circumstances of a given licensee's organization.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] The techniques introduced here may be better understood by referring to the following Detailed Description in conjunction with the accompanying drawings, in which like reference numerals indicate identical or functionally similar elements:
[0006] FIG. 1 is an example license hierarchy as may apply in some embodiments;
[0007] FIG. 2 is an example deployment system topology for optimizing license assignments as contemplated in some embodiments;
[0008] FIG. 3 is an example system topology for a manager system and deployment system optimizing license assignments as contemplated in some embodiments;
[0009] FIGS. 4 and 5 are a flow diagram depicting various steps in a license optimization process as may be implemented in some embodiments;
[0010] FIG. 6 depicts example entities as may be applied in some embodiments;
[0011] FIG. 7 is a flow diagram depicting various steps in a license recommendation process (e.g., as may occur in block 420 in some embodiments) as may be implemented in some embodiments;
[0012] FIG. 8 is a flow diagram depicting various steps in a license recommendation process (e.g., as may occur in block 425 in some embodiments) as may be implemented in some embodiments;
[0013] FIG. 9 is a flow diagram depicting various steps in a license update process (e.g., as may occur in block 435 in some embodiments) as may be implemented in some embodiments;
[0014] FIG. 10 is a flow diagram depicting various steps in a license update process (e.g., as may occur in block 440 in some embodiments) as may be implemented in some embodiments; and
[0015] FIG. 11 is a block diagram of a computer system as may be used to implement features of some of the embodiments.
[0016] While the flow and sequence diagrams presented herein show an organization designed to make them more comprehensible by a human reader, those skilled in the art will appreciate that actual data structures used to store this information may differ from what is shown, in that they, for example, may be organized in a different manner; may contain more or less information than shown; may be compressed and/or encrypted; etc.
[0017] The headings provided herein are for convenience only and do not necessarily affect the scope or meaning of the embodiments. Further, the drawings have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be expanded or reduced to help improve the understanding of the embodiments. Similarly, some components and/or operations may be separated into different blocks or combined into a single block for the purposes of discussion of some of the embodiments. Moreover, while the various embodiments are amenable to various modifications and alternative forms, specific embodiments have been shown by way of example in the drawings and are described in detail below. The intention, however, is not to limit the particular embodiments described. On the contrary, the embodiments are intended to cover all modifications, equivalents, and alternatives falling within the scope of the disclosed embodiments.
DETAILED DESCRIPTION
[0018] Various examples of the disclosed techniques will now be described in further detail. The following description provides specific details for a thorough understanding and enabling description of these examples. One skilled in the relevant art will understand, however, that the techniques discussed herein may be practiced without many of these details. Likewise, one skilled in the relevant art will also understand that the techniques can include many other obvious features not described in detail herein. Additionally, some well-known structures or functions may not be shown or described in detail below, so as to avoid unnecessarily obscuring the relevant description.
[0019] The terminology used below is to be interpreted in its broadest reasonable manner, even though it is being used in conjunction with a detailed description of certain specific examples of the embodiments. Indeed, certain terms may even be emphasized below; however, any terminology intended to be interpreted in any restricted manner will be overtly and specifically defined as such in this section.
Overview
[0020] Many organizations rely heavily upon disparate collections of licensed software associated with various licensing terms and conditions. For example, SAP SE® provides various software solutions under different licensing terms. Organizations using SAP® software (or a similar organization) may have contracts stipulating a “license ratio” condition. The “license ratio” is a minimum ratio between (but not limited to) two license types. For example, given hypothetical license type A and hypothetical license type B, an NB ratio of ¼ may require that there be at least four times as many B licenses as A licenses in effect at any time during the agreement. Due to this contract requirement, the organization may be responsible for ensuring that the number of licenses that have been purchased meets the minimum ratio. In some agreements, each time additional licenses are purchased, the purchaser must ensure that the ratio is maintained. Thus, the terms may reflect an ongoing obligation rather than just an agreement regarding the initial purchases of the license (though in some embodiments, only an initial requirement may be imposed). In some contracts, the ratio is between groups of licenses, e.g., the ratio of one license to a group of two or more license, or the ratio of a group of two or more licenses to another group of two or more licenses. In these instances, each active instance of a license may contribute to the total for the group.
[0021] To facilitate discussion in this document, a license ratio requirement is assumed to exist between two hypothetical license types: “LicenseTypeA” and “LicenseTypeB”. A hypothetical contract may state that there exists a minimum ratio between the numbers of licenses purchased of each license type. For example of the total licenses of type LicenseTypeA and LicenseTypeB owned by an organization, the agreement may require that 40% of the active software instances (e.g., a number of processes across a computer network) be under LicenseTypeA and 60% must be under LicenseTypeB. It is further assumed in some instances that the license type that allows a user to access greater functionality within the licensing organization (e.g., SAP®) has a higher priority in the license type hierarchy and accordingly has the higher ratio percentage (e.g., LicenseTypeB would be higher than LicenseTypeA as it receives 60%). The license type hierarchy may be defined by the licensor (e.g., SAP®) and may represent the amount of functionality a user can access based on a specific license type. An example of a subset of the SAP license type hierarchy can be seen in FIG. 1 . The exemplary blocks in FIG. 1 refer to the different license types available from the vendor. As shown in this example, the highest priority licenses are indicated at the top of the tree, with increasingly less prioritized licenses provided below. The licenses may be ordered in a total or partial ordering based upon their level in the tree. Accordingly, the ratio may require that fewer licenses lower in the tree be in effect when licenses higher in the tree are in effect (or vice versa in some circumstances).
Example System Topology Overview
[0022] FIG. 2 is an example deployment system 200 topology for optimizing license assignments as contemplated in some embodiments. A central system 210 , may run one or more monitoring programs which coordinate license assignments for client systems 220 a - f across a computer network 215 . A license database 205 may include information indicating terms of an agreement between a license provider and a licensee. For example, access to software and/or services from a licensor server system 225 may be predicated upon compliance with the conditions of the license agreement.
[0023] In this example, the agreement mandates a ratio of no more than ½ between Licenses A and B. At the depicted time, client systems 220 a , 220 b , 220 c , and 220 f may be in use while systems 220 d and 220 e are inactive (one will recognize that independent machines are depicted here for clarity, but that actual license terms may mandate a number of processes/threads running, regardless of whether they run on one or many machines). Thus, at present, it is acceptable for client system 220 a to run License A, while systems 220 b , 220 c , and 220 f run License B (presenting 1 active License A instance for 3 active License B instances, or a ratio of ⅓ which is <=½). However, if a new system is brought online, e.g., system 220 d , it will not be able to instantiate a software or service under License A as doing so would exceed the mandated ratio (i.e., a ratio of ⅔ which is >½). If system 220 d instead instantiates License B, a user subsequently beginning a session on system 220 e may have the choice of using either License A or License B (as instantiating either would result in License A to License B ratios of ½ or ⅕ respectively, each of which are <=½). Complications can arise, however, when users close instances. For example, a user engaged in a session under License A may suddenly be required to transition to License B if a sufficient number of License B sessions are closed (some contracts may permit existing instances to continue so long as new instances are only created in compliance with the mandated ratio).
[0024] Accordingly, the central system 210 , may coordinate licenses to optimize their compliant usage under the terms of the agreement. As discussed herein, the central system 210 may be integrated with the network such that license ratios are properly maintained in an effective and streamlined manner. Though the central system 210 is depicted here as a single, overarching device, one will recognize topologies wherein the central system 210 is distributed among client systems, shared among multiple devices, etc.
[0025] FIG. 3 is an example system topology for a manager system and deployment system optimizing license assignments as contemplated in some embodiments. A deployment system 200 such as the one previously described in FIG. 2 may communicate with an application manager 305 locally or remotely, e.g., across a network. The application manager 305 may include a corpus of information and tools 310 , including, e.g., reports 310 a , analysis results 310 b , a user GUI dashboard 310 c , licensing rules 310 d , etc. Business rules at the application manager 305 may be used by the system to derive recommendations 315 from this information corpus. The deployment system 200 may report usage data 320 to the application manager 305 at various times, which may be used to supplement the corpus of information 310 . Thus, the deployed system 200 may be managed by central system 210 , but central system 210 may itself interact with an application manager 305 to optimize its behavior to a particular licensee's circumstances. In some embodiments, the central system 210 may incorporate, or contain, application manager 305 .
Example Central System Operation Overview
[0026] Some computer system embodiments obtain an optimal license position for an organization by analyzing an organization's current license assignments and then comparing usage data against optimization rules defined by the organization (e.g., as specified in application manager 305 or central system 210 ). In this manner, the optimal license type for each user can be recommended or assigned. A license breach may occur when there aren't enough purchases of a license type to cover the necessary assignments of that license type (e.g., to meet the ratio requirement, 30 licenses must be in effect, but only 10 are available).
[0027] Various computer system embodiments include a mechanism for considering the existence of a license ratio within the user's contract. The system may calculate the optimal license position and remove as many license breaches as possible by re-using as many, if any, spare superior (higher priority) licenses as are available. This process may be independent of the initial license assignment recommendation. The process may activate or deactivate at any time during the calculation of a license position in some embodiments.
[0028] In some embodiments, the computer process begins with the calculation of the most optimal license position 405 based upon, e.g., the user consolidation, optimization and duplicate creation of user rules. The system may check if a license ratio has been defined and activated at block 410 . If a ratio has not been defined, the system may move on to the block 445 and then 505 of possibly promoting users to spare superior (higher priority) licenses.
[0029] If a license ratio is defined and active at block 410 , the system may then enforce the license beginning at block 415 . The respective percentage values for each license type may be retrieved and stored at block 415 along with the optimal license count for both license types that have been calculated earlier in the process. The system may then calculate the recommended license counts for both license types of the license ratio at blocks 420 and 425 (as well as the other licenses if more than two licenses are being considered).
[0030] FIG. 7 is a flow diagram depicting various steps in a license recommendation process (e.g., as may occur in block 420 in some embodiments) as may be implemented in some embodiments. At block 705 , the recommended license count may be calculated by identifying the lower priority license type and then comparing that license count to determine whether the percentage value of this license type is less than or equal to the percentage value of the higher priority license type. If the lower priority license satisfies this condition, then the system may proceed to block 710 .
[0031] If the optimal license count of the lower priority license type is less than the sum of both license types multiplied by the lower priority license type percentage value, then the recommended license count may be equal to the optimal license count for that license type at block 715 . However if the optimal license count of the lower priority license type is greater than or equal to the sum of the both license types multiplied by the lower priority license type percentage value, then the recommended license count may be the sum of the both license types multiplied by the lower priority license type percentage value rounded down to the nearest whole number as indicated at block 720 .
[0032] If the percentage value of the lower priority license type is greater than the percentage value of the higher priority license type then the computer system may check at block 725 to see if the optimal license count of the lower priority license type is greater than or equal to the sum of both license types multiplied by the lower priority license type percentage value. If this condition is met, then at block 730 , the recommended license count may be equal to the optimal license count for that license type.
[0033] If the condition is not met, then at block 735 the recommended license count may be the sum of both license types multiplied by the lower priority license type percentage value rounded up to the nearest whole number. An analogous process may then be followed for the higher priority license type as indicated in FIG. 8 for block 425 . At this point the system may now have the constrained license position, that is, the optimal license position updated to include the constraints of a license ratio.
[0034] Returning to the process of FIG. 4 , FIG. 9 is a flow diagram depicting various steps in a license update process (e.g., as may occur in block 435 in some embodiments) as may be implemented in some embodiments. FIG. 10 is another flow diagram depicting various steps in a license update process (e.g., as may occur in block 440 in some embodiments for a higher priority license) as may be implemented in some embodiments. The license position may then be retrieved at block 445 .
[0035] The process of FIG. 4 is continued in FIG. 5 , where blocks 505 and 510 the computer system may then determine if any license types that are in breach can be brought back into compliance by using spare licenses of a superior license type. As with license ratios, the system may first check if the option to use spare license purchases is active (e.g., the option may be set by an administrator, by a term in the license database, etc.). If the option is not active, the system may return the current license position.
[0036] However, if the option is active, the computer system may then build up two separate lists. One list may contain all license types that have spare licenses available and the other list may contain a list of license types that are in breach. Both lists may then be ordered at block 515 based upon the predefined license type hierarchy, e.g., as defined by the license provider (e.g., SAP®). The system may then iterate through these lists, comparing the parent license type of each item in the breach list to the license type of the items in the spare list. When a match is found the computer system may reassign the first user with the breached license type at block 525 such that they now use the license type of one of the spare licenses. These updates may avoid the need to purchase an extra license. License substitutions may continue until there are either no more spare licenses or all breaches have been removed as determined at block 530 . At this point the computer system may return the final license position.
Example Entities
[0037] FIG. 6 depicts example entities 600 as may be applied in some embodiments. The “optional license count” may specify the count of licenses without any licensing constraints being taken into consideration. In contrast, the “recommended license count” may reflect the license count with constraints taken into consideration.
User License Adjustment
[0038] One will recognize that in all the examples provided herein LicenseTypeA and LicenseTypeB are considered as single licenses for purposes of clarity to facilitate understanding. As discussed, groups of licenses rather than single licenses may be managed, mutatis mutandis, using the systems and methods described herein.
Computer System
[0039] FIG. 11 is a block diagram of a computer system as may be used to implement features of some embodiments. The computing system 1100 may include one or more central processing units (“processors”) 1105 , memory 1110 , input/output devices 1125 (e.g., keyboard and pointing devices, display devices), storage devices 1120 (e.g., disk drives), and network adapters 1130 (e.g., network interfaces) that are connected to an interconnect 1115 . The interconnect 1115 is illustrated as an abstraction that represents any one or more separate physical buses, point to point connections, or both connected by appropriate bridges, adapters, or controllers. The interconnect 1115 , therefore, may include, for example, a system bus, a Peripheral Component Interconnect (PCI) bus or PCI-Express bus, a HyperTransport or industry standard architecture (ISA) bus, a small computer system interface (SCSI) bus, a universal serial bus (USB), IIC (I2C) bus, or an Institute of Electrical and Electronics Engineers (IEEE) standard 1394 bus, also called “Firewire”.
[0040] The memory 1110 and storage devices 1120 are computer-readable storage media that may store instructions that implement at least portions of the various embodiments. In addition, the data structures and message structures may be stored or transmitted via a data transmission medium, e.g., a signal on a communications link. Various communications links may be used, e.g., the Internet, a local area network, a wide area network, or a point-to-point dial-up connection. Thus, computer readable media can include computer-readable storage media (e.g., “non transitory” media) and computer-readable transmission media.
[0041] The instructions stored in memory 1110 can be implemented as software and/or firmware to program the processor(s) 1105 to carry out actions described above. In some embodiments, such software or firmware may be initially provided to the processing system 1100 by downloading it from a remote system through the computing system 1100 (e.g., via network adapter 1130 ).
[0042] The various embodiments introduced herein can be implemented by, for example, programmable circuitry (e.g., one or more microprocessors) programmed with software and/or firmware, or entirely in special-purpose hardwired (non-programmable) circuitry, or in a combination of such forms. Special-purpose hardwired circuitry may be in the form of, for example, one or more ASICs, PLDs, FPGAs, etc.
Remarks
[0043] The above description and drawings are illustrative and are not to be construed as limiting. Numerous specific details are described to provide a thorough understanding of the disclosure. However, in certain instances, well-known details are not described in order to avoid obscuring the description. Further, various modifications may be made without deviating from the scope of the embodiments.
[0044] Reference in this specification to “one embodiment” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the disclosure. The appearances of the phrase “in one embodiment” in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Moreover, various features are described which may be exhibited by some embodiments and not by others. Similarly, various requirements are described which may be requirements for some embodiments but not for other embodiments.
[0045] The terms used in this specification generally have their ordinary meanings in the art, within the context of the disclosure, and in the specific context where each term is used. Certain terms that are used to describe the disclosure are discussed below, or elsewhere in the specification, to provide additional guidance to the practitioner regarding the description of the disclosure. For convenience, certain terms may be highlighted, for example using italics and/or quotation marks. The use of highlighting has no influence on the scope and meaning of a term; the scope and meaning of a term is the same, in the same context, whether or not it is highlighted. It will be appreciated that the same thing can be said in more than one way. One will recognize that “memory” is one form of a “storage” and that the terms may on occasion be used interchangeably.
[0046] Consequently, alternative language and synonyms may be used for any one or more of the terms discussed herein, nor is any special significance to be placed upon whether or not a term is elaborated or discussed herein. Synonyms for certain terms are provided. A recital of one or more synonyms does not exclude the use of other synonyms. The use of examples anywhere in this specification including examples of any term discussed herein is illustrative only, and is not intended to further limit the scope and meaning of the disclosure or of any exemplified term. Likewise, the disclosure is not limited to various embodiments given in this specification.
[0047] Without intent to further limit the scope of the disclosure, examples of instruments, apparatus, methods and their related results according to the embodiments of the present disclosure are given above. Note that titles or subtitles may be used in the examples for convenience of a reader, which in no way should limit the scope of the disclosure. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains. In the case of conflict, the present document, including definitions will control.
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Systems and methods for managing and optimizing licensing restrictions for deployed systems are presented. Particularly, a central system may be used to coordinate license assignments to a plurality of users in accordance with ratios mandated as part of a licensing agreement. The system may reassess the ratios after deployment and may adjust licensing allocations to preserve the ratio, as well as to better accord with usage behavior by the organization as a whole. Some embodiments employment specific enforcement provisions, mandating the recommended licensing percentage for a license type based upon scaled sums of optimal ratio values for different license types.
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CROSS-REFERENCE TO RELATED APPLICATIONS
This Application is a non-provisional application claiming priority to provisional application 61/526,808 filed on Aug. 24, 2011, under 35 USC 119(e). The entire disclosure of the provisional application is incorporated herein by reference.
BACKGROUND
Methods and systems disclosed herein relate generally to display features that could be distracting. Most eye-trackers come equipped with software to analyze the eye-movements of individual participants, including fixations and saccades (eye movements between fixations). What is needed is a method that combines and compiles fixations of multiple participants.
SUMMARY
The system and method of the present embodiment analyze multiple participants' eye-movements (specifically, fixations) over a visual display (e.g., anything displayed on a computer screen) to determine which features on the display universally attract the most attention, or are the most distracting. Eye movement data are generally recorded by an eye-tracking device as either fixations (when visual attention is focused on an item in the field of view) or saccades (when there is eye movement—and therefore a change in visual attention—from one fixation to another). A saccade is detected when eye movement velocity is more than a predetermined speed (e.g., 30 degrees of visual angle per second), and a fixation is detected when eye movement velocity is less than that speed. When a region of interest is fixated upon (which subtends approximately 2 degrees of visual angle), that region is brought into focus and, the observer may be attending to and attempting to perceive and understand the information there. By recording and then clustering many observers' fixations over a common display, the regions of the display that are universally attracting people's attention can be analyzed.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a pictorial representation of a digital aeronautical chart overlaid with locations of fixations from 24 participants;
FIG. 2 is the chart of FIG. 1 with all fixations within 0.5° visual angle of each other clustered together;
FIG. 3 is the chart of FIG. 1 showing fixations color-coded by participant;
FIG. 4 is the chart of FIG. 1 with the “most visited” cluster of fixations highlighted and all other clusters grayed out;
FIG. 5 is the chart of FIG. 1 with only the “most visited” cluster of fixations plotted thereon;
FIG. 6 is the chart of FIG. 1 with the “most visited” cluster expanded to represent at least 2° of visual angle, revealing the most distracting feature of the chart (the red town);
FIG. 7 is a flowchart of the method of the present embodiment;
FIG. 8 is a schematic block diagram of the system of the present embodiment; and
FIG. 9 is a schematic block diagram of the cluster processor of the present embodiment.
DETAILED DESCRIPTION
The problems set forth above as well as further and other problems are solved by the present teachings. These solutions and other advantages are achieved by the various embodiments of the teachings described herein below.
The invention is a computer system and method for determining distracting features on an electronic visual display. The system and method cluster multiple observers' fixations, and track various information for each fixation, including (as a minimum) the screen location (X and Y) of the fixation and a unique index number representing the participant who made the fixation. Any other information that was measured in association with the fixation can also be tracked. Counts, averages, standard deviations, and other statistical analyses of the information for each cluster of fixations can be determined. This additional information could include, but is not limited to including, the length (dwell time) of the clustered fixations, the direction and length of previous or following saccades, the amount of clutter immediately surrounding the fixation (as measured by various clutter models), and the average salience of features immediately surrounding the fixation (as measured by various saliency models). The system and method of the present embodiment can be used to filter all the fixation clusters by number of observers, such that only clusters containing at least a pre-selected minimum number (or a maximum number, for a given display) of observers' fixations are analyzed. One method of viewing the resulting clusters is to save them as shapefiles and view/analyze them with ARCINFO® or ARCGIS®.
In the present embodiment, fixations for twenty-four observers are included. The following fixations can be, but are not required to be, excluded from clustering: (1) first fixation for each observer/map (center point fixation); (2) all fixations after each observer completed any assigned tasks (e.g., if this was a target detection task, omit all fixations after the observer detected the target); and (3) all fixations for a trial suspected of eye-tracker drift. Clusters are created using, for example, but not limited to, a circular expansion of size five pixels (diameter=10 pix, or 0.5° visual angle). Thus, in the present embodiment, the furthest that two fixations could be separated and still be clustered together would be 0.5°. Clusters containing fixations from at least a pre-selected number of different observers, for example, but not limited to, six or 25% of the observer pool in the exemplary configuration, are shown. In this example, the largest number of observers that were represented in a single cluster was six. After removing the smallest clusters (with, for example, but not limited to, <6 observers' fixations), a border of pre-selected pixel width, for example, but not limited to, fifteen pixels, is added to the remaining clusters, resulting in a minimum of a forty pixel diameter (2° visual angle) per cluster, to make it easier to see what feature is being viewed. All values denoted as “pre-selected” could be constant, computed, retrieved from electronic storage, or user-selected, for example.
Referring now to FIG. 1 , an exemplary chart is shown upon which the method of the present embodiment is pictorially illustrated. In this example, all fixations 125 for twenty-four observers are included, except (1) the first fixation for each observer/map (center point fixation), (2) all fixations after each observer completed an assigned task (e.g., clicking on a randomly placed target feature, not shown in this image), and (3) all fixations for a trial suspected of eye-tracker drift.
Referring now to FIG. 2 , all fixations 125 ( FIG. 1 ) within 0.5° visual angle of each other are clustered together. In the present embodiment, clusters 129 are created using a circular expansion of size 5 (diameter=10 pix, or 0.5° visual angle). Thus, the farthest that two fixations 125 ( FIG. 1 ) are separated and still be clustered together is 0.5°.
Referring now to FIG. 3 , clusters 129 ( FIG. 2 ) are shown with color-coded fixations 130 , color-coded by observer 127 ( FIG. 8 ). Only clusters 129 ( FIG. 2 ) containing fixations 125 ( FIG. 1 ) from at least six different observers 127 ( FIG. 8 ) (25% of the observer pool) are retained.
Referring now to FIG. 4 , only one processed clustered fixation 131 has fixations 125 ( FIG. 1 ) from at least six different observers.
Referring now to FIG. 5 , the smallest of clusters 129 ( FIG. 2 ) (with fewer than six different observers' fixations) have been removed. In the present embodiment, a fifteen-pixel border is added to the remaining of clusters 129 ( FIG. 2 ), resulting in a minimum forty-pixel diameter (2° visual angle) per isolated clustered fixation 133 , to make it easier to see the feature that is viewed by the observers.
Referring now to FIG. 6 , the underlying chart 134 of FIG. 1 corresponding to the isolated clustered fixation 133 ( FIG. 5 ), which became the subject of most observers' fixations, as isolated by the method of the present embodiment is shown.
Referring now to FIG. 7 , method 150 for analyzing multiple observers' fixations, recorded by an eye-tracker, over a visual display to determine distracting features, can include, but is not limited to including, the steps of automatically detecting 151 fixations on an electronic display, each of the fixations being associated with an observer, automatically clustering 153 together the fixations within a pre-selected visual angle of other of the fixations, automatically isolating 155 the clustered fixations associated with at least a preselected number of different observers, automatically removing 157 the fixations that are not part of the isolated clustered fixations, automatically expanding 159 the isolated clustered fixations to represent a pre-selected output visual angle, and automatically providing 161 the expanded isolated clustered fixations as the distracting features. The pre-selected visual angle can optionally be user-selected. The pre-selected number of different observers can optionally be a pre-selected percentage of the total number of the observers. The pre-selected output visual angle can optionally be user-selected. The step of detecting fixations can include, but is not limited to including, the step of configuring an electronic automated device for detecting the fixations. Optionally, method 150 can include the step of planting targets and distractors on the display. Method 150 can optionally include the step of excluding predetermined fixations, where the predetermined fixations can include, but are not limited to including, the first fixation in each trial, the fixations following the successful completion of some task, the fixations deemed to be affected by drift of the eye tracking device, and fixations over specified features. The step of expanding can include, but is not limited to including, the step of adding a border of pre-selected pixel width to the isolated clustered fixations. The pre-selected pixel width can optionally be user-selected.
Optional steps can include (1) while forming each cluster, automatically calculating and maintaining a running summation and count of various measureable parameters associated with each fixation in each cluster, including, but not limited to including, (a) the number of unique observers represented by the fixations in each cluster; (b) the duration (in milliseconds) of each of the fixations in each cluster; (c) the index (i.e., location in time, per trial) of each fixation in each cluster; (d) any other measureable, user-specified parameters associated with each fixation in each cluster; (2) after forming each cluster, automatically calculating the final number of unique observers represented by the fixations in each cluster; and standard statistical measures (e.g., minimum, maximum, average, median, mode, standard deviation, etc.) for each measurable parameter calculated for the fixations in each cluster; and (3) automatically providing the clustered fixation statistics for each distracting feature.
The method of the present embodiment could be implemented as executable computer code configured with, for example, but not limited to: (1) default values for clustering resolution, e.g. 10, and the clustering radius, e.g. 5 (such that 2 points would be clustered together if they are 10 (or fewer) pixels apart); (2) the location of the fixations input file; (3) the location in which are to be written the output files, e.g. shapefiles; (4) a flag to indicate whether a) exact point locations are used or b) point locations are “snapped” to the nearest grid location, based on a preset resolution; (5) the resolution (in pixels) if the previous flag is set to “snap” to a grid; and (6) a flag to indicate whether or not to smooth the cluster boundaries, which a) would compress the final cluster file and b) might in some cases (e.g., for very complex cluster boundaries) produce cleaner, less jagged-looking cluster boundaries. The executable computer code could be invoked with parameters such as, for example, but not limited to, (1) a unique identifier per fixation; (2) the screen coordinates of the fixation; (3) the observer's identifier; (4) the fixation length (amount of time fixated, in milliseconds); and (5) the average clutter and saliency of the region immediately surrounding the fixation (e.g., 2° of visual angle centered on the fixation point).
Referring now to FIG. 8 , system 100 for analyzing multiple observers' fixations, recorded by tracking device 140 , over a visual display 138 to determine distracting features 135 , can include, but is not limited to including, fixation processor 101 including, but not limited to, detector 103 automatically detecting, from tracking device data 126 , fixations 125 on visual display 138 , each fixation 125 being associated with one of a plurality of observers 127 , cluster processor 105 automatically clustering together fixations 125 within pre-selected visual angle 115 of other of fixations 125 , isolator 107 automatically isolating clustered fixations 129 associated with at least preselected number 119 of different observers 127 , remover 109 automatically removing fixations 125 that are not part of processed clustered fixations 131 , expander 111 automatically expanding isolated clustered fixations 133 to represent pre-selected output visual angle 122 , expander 111 automatically providing to chart processor 123 expanded isolated clustered fixations as distracting features 135 . Pre-selected visual angle 115 can optionally be user-selected. Pre-selected number 119 of different observers 127 can optionally be pre-selected percentage 117 of the total number of the observers 127 . Pre-selected output visual angle 115 can optionally be user-selected. Detector 103 can optionally provide configuration information 121 to tracking device 140 for detecting fixations 125 . Detector 103 can also plant targets 15 and distractors 13 on the display. Optionally, excluder 113 can exclude predetermined of fixations 125 , where the predetermined of fixations 125 can include, but are not limited to including, the first of fixations 125 in each trial, fixations 125 following the successful completion of a task, fixations 125 deemed to be affected by drift of tracking device 140 , and fixations 125 over specified features. Expander 111 can optionally add a border of pre-selected pixel width to isolated clustered fixations 133 . The pre-selected pixel width can optionally be user-selected.
Referring now to FIG. 9 , cluster processor 105 can include, but is not limited to including, cluster statistics processor 137 automatically calculating and maintaining measureable parameters statistics 136 associated with each fixation 125 in each of clustered fixations 129 , including, but not limited to including, (a) the number of unique observers 127 represented by fixations 125 in each of clustered fixations 129 ; (b) the duration (in milliseconds) of each of the fixations 125 in each of clustered fixations 129 ; (c) the index (i.e., location in time, per trial) of each fixation 125 in each of clustered fixations 129 ; (d) any other measureable, user-specified parameters associated with each fixation 125 in each of clustered fixations 129 ; (2) after forming each of clustered fixations 129 , automatically calculating the final number of unique of observers 127 represented by fixations 125 in each of clustered fixations 129 ; and standard statistical measures (e.g., minimum, maximum, average, median, mode, standard deviation, etc.) for each measurable parameter calculated for the fixations 125 in each of clustered fixations 129 . Cluster processor 105 can also include distractions statistics processor 139 automatically providing the clustered fixation statistics 134 for each distracting feature 135 .
Embodiments of the present teachings are directed to computer systems for accomplishing the methods discussed in the description herein, and to computer readable media containing programs for accomplishing these methods. The raw data and results can be stored for future retrieval and processing, printed, displayed, transferred to another computer, and/or transferred elsewhere. Communications links can be wired or wireless, for example, using cellular communication systems, military communications systems, and satellite communications systems. In an exemplary embodiment, the software for the system is written in Fortran and C. The system operates on a computer having a variable number of CPUs. Other alternative computer platforms can be used. The operating system can be, for example, but is not limited to, WINDOWS® or LINUX®.
The present embodiment is also directed to software for accomplishing the methods discussed herein, and computer readable media storing software for accomplishing these methods. The various modules described herein can be accomplished on the same CPU, or can be accomplished on a different computer. In compliance with the statute, the present embodiment has been described in language more or less specific as to structural and methodical features. It is to be understood, however, that the present embodiment is not limited to the specific features shown and described, since the means herein disclosed comprise preferred forms of putting the present embodiment into effect.
Referring again primarily to FIG. 7 , method 150 can be, in whole or in part, implemented electronically. Signals representing actions taken by elements of system 100 ( FIG. 8 ) and other disclosed embodiments can travel over at least one live communications network. Control and data information can be electronically executed and stored on at least one computer-readable medium. The system can be implemented to execute on at least one computer node in at least one live communications network. Common forms of at least one computer-readable medium can include, for example, but not be limited to, a floppy disk, a flexible disk, a hard disk, magnetic tape, or any other magnetic medium, a compact disk read only memory or any other optical medium, punched cards, paper tape, or any other physical medium with patterns of holes, a random access memory, a programmable read only memory, and erasable programmable read only memory (EPROM), a Flash EPROM, or any other memory chip or cartridge, or any other medium from which a computer can read. Further, the at least one computer readable medium can contain graphs in any form including, but not limited to, Graphic Interchange Format (GIF), Joint Photographic Experts Group (JPEG), Portable Network Graphics (PNG), Scalable Vector Graphics (SVG), and Tagged Image File Format (TIFF).
Although the present teachings have been described with respect to various embodiments, it should be realized these teachings are also capable of a wide variety of further and other embodiments.
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System and method for analyzing multiple participants' eye-movements over a visual display to determine which features on the display universally attract the most attention, or are the most distracting.
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The present application claims benefit under 35 U.S.C. §119 (e) to U.S. provisional patent application 61/095,854, filed Sep. 10, 2008, and U.S. provisional patent application 61/095,869, filed Sep. 10, 2008, the entire disclosures of which are incorporated herein by reference.
BACKGROUND
In the middle of the twentieth century, comic strip detective Dick Tracy was famous for his two-way wrist radio. Comic strip readers probably considered that radio a fanciful invention of science fiction. Today, cellular telephones, wireless Internet connections, keyless automobile control, wireless game controllers, and many other everyday wireless devices have features that Dick Tracy would not have imagined. Today's wireless devices require small, low-cost integrated circuit transmitters, and they often use sophisticated methods of controlling the power output of the transmitter, for extending battery life and for transmitting data. They also need to work across different wireless standards and multiple frequency bands.
Modulation is the process of combining analog or digital data with a carrier signal for transmission. FIG. 1 illustrates a conceptual view of a modulator 100 .
In operation, modulator 100 combines an information signal 102 with a carrier signal 104 to create a modulated carrier signal 106 . Carrier signal 104 is often a radio frequency (RF) signal, but other carrier signals are possible. For example, the carrier signal could be coherent light from a laser.
FIG. 2 illustrates a conventional transmitter 200 with quadrature amplitude modulation (QAM). QAM is a method of sending two information signals on one carrier.
As illustrated in FIG. 2 , transmitter 200 comprises a digital-to-analog converter (DAC) 204 , a low pass filter 206 , a local oscillator 208 , a multiplier 210 , a DAC 214 , a low pass filter 216 , a local oscillator 218 , a multiplier 220 , an adder 222 , a variable gain amplifier (VGA) 224 , a VGA 226 , an impedance matching device 228 and a load 230 . Load 230 could, for example, be an antenna or a power amplifier.
DAC 204 is arranged to receive I-Data 202 and to output a signal 232 . Low pass filter 206 is arranged to receive signal 232 and output a signal 234 . Local oscillator 208 is arranged to provide a carrier signal 236 . Multiplier 210 is arranged to receive single 234 and carrier signal 236 and to output a signal 238 .
DAC 214 is arranged to receive I-Data 212 and to output a signal 213 . Low pass filter 216 is arranged to receive signal 213 and output a signal 247 . Local oscillator 218 is arranged to provide a carrier signal 245 . Multiplier 220 is arranged to receive signal 247 and carrier signal 245 and to output a signal 248 .
Adder 222 is arranged to receive signal 238 and signal 248 and to output a signal 240 . VGA 224 is arranged to receive signal 240 and to output a signal 242 . VGA 226 is arranged to receive signal 242 and output a signal 244 . Impedance matching device 228 is arranged to receive signal 244 and output a signal 246 . Load 230 is arranged to receive signal 246 and is connected to ground.
In operation, local oscillators 208 and 218 both operate at the same carrier frequency at which transmitter 200 will be operating. Carrier signal 236 provided by local oscillator 208 is in quadrature with carrier signal 245 provided by local oscillator 218 , meaning that carrier signals 236 and 245 have the same frequency but differ in phase by 90°. DAC 204 , low pass filter 206 and multiplier 210 make up an in-phase leg of transmitter 200 . DAC 214 , low pass filter 216 , oscillator 218 and multiplier 220 make up a quadrature leg of transmitter 200 .
DAC 204 converts I-Data 202 data from digital to analog. Low pass filter 206 removes high frequency quantization noise from signal 232 . Multiplier 210 multiplies signal 234 with carrier signal 236 to create signal 238 , which is carrier signal 236 modulated by signal 234 .
DAC 214 converts Q-Data 212 data from digital to analog. Low pass filter 216 removes high frequency quantization noise from signal 213 . Multiplier 220 multiplies signal 247 with carrier signal 245 to create signal 248 , which is carrier signal 245 modulated by signal 247 .
Adder 222 creates signal 240 by adding signals 238 and 248 . Signal 240 is amplified by VGA 224 . Signal 242 is amplified by VGA 226 . Both VGA 224 and VGA 226 provide gain control in the form of amplification or attenuation.
Transmitter 200 has several problems. If, for example, transmitter 200 is implemented as a conventional CMOS integrated circuit, many current-to-voltage and voltage-to-current conversions are required as signals move from the output of one functional block to the input of the next functional block. For example, a current-to-voltage conversion would be required at DAC 204 output, while low pass filter 206 needs to convert signal 234 from an input voltage to an input current. The input current needs to be converted to a voltage at the output of low pass filter 206 as signal 234 . Current-to-voltage and voltage-to-current conversions introduce undesirable nonlinearities. These conversions also cause undesirable increases in power consumption and in noise, and these conversions have the undesirable side effect of increasing the number of devices needed in the integrated circuit.
If transmitter 200 is implemented in a technology other than bipolar transistors, problems arise in adjusting the gain of VGA 224 and VGA 226 .
FIG. 3 illustrates a conventional system 300 used to control the gain of a VGA in a conventional transmitter.
System 300 includes a linear to exponential converter 302 and a bipolar VGA 304 . Converter 302 is arranged to receive a linear control voltage 306 and to output an exponential signal 308 . Bipolar VGA 304 is arranged to receive an input signal 310 and output an amplified or attenuated signal 312 .
In operation, converter 302 performs the mathematical function of taking the exponential value of linear control voltage 306 . Exponential signal 308 is exponentially related to linear control voltage 306 . Exponential signal 308 is used to control the gain of VGA 304 .
Because the collector current of a bipolar transistor is exponentially related to the base-to-emitter voltage, converter 302 can be easily implemented with a bipolar transistor. In other technologies, however, a linear to exponential converter similar to 302 cannot be easily implemented.
The gain control of system 300 will now be described with reference to FIG. 4 .
FIG. 4 is a graph, wherein the x-axis corresponds to linear control voltage 306 , and the y-axis is the output power of VGA 304 . Arbitrary x-axis values are shown going from 0 to 1023 because it is assumed, for purposes of example, that linear control voltage 306 is provided by a 10-bit digital-to-analog converter. The y-axis units are dBm. The dBm scale is a logarithmic scale in which 1 milliwatt is taken as zero. A power P, in milliwatts, can be expressed as 10 log (P) dBm.
A line 402 in FIG. 4 is a straight line because the dBm scale is a logarithmic scale and because the output power from VGA 304 is proportional to the exponential of linear control voltage 306 . This linear relationship between linear control voltage 306 and output power from VGA 304 , expressed in dBm, is the desired relationship for transmitter 200 .
FIG. 5 illustrates an example of a CMOS VGA circuit 500 using a conventional method for controlling power output.
As illustrated in FIG. 5 , CMOS VGA circuit 500 includes NMOS FETs 502 , 504 , 506 , 508 , 510 and 512 . CMOS VGA circuit 500 is connected to a center-tapped load 514 .
The gates of FETs 502 and 512 are connected to a control voltage V ON 516 . The gates of FETs 504 and 510 are connected to a control voltage V 1 528 . The gates of FETs 506 and 508 are connected to a control voltage V 2 530 . FETs 502 and 512 are each a single FET. Although FETs 504 , 506 , 508 and 510 are each illustrated as a single FET, each of FETs 504 , 506 , 508 and 510 is an arrangement of multiple (100 in this example) FETs. The number of FETs depend on the total desired gain control range.
Control voltage V ON 516 is at its maximum value whenever CMOS VGA circuit 500 is operational. When control voltage V 1 528 is at its maximum value and control voltage V 2 530 is at zero volts, no current flows through FET 506 . In this case, a current I 0 + 524 is equal to a current I RF + 526 . Similarly, when control voltage V 1 528 is at its maximum value and control voltage V 2 530 is at zero volts, no current flows through FET 508 . In this case, a current I 0 − 532 is equal to a current I RF − 534 .
Further, when control voltage V 1 528 is at its maximum value and control voltage V 2 530 is zero, CMOS VGA circuit 500 provides maximum power to load 514 . FET 504 , which is controlled by control voltage V 1 528 , is an arrangement of 100 FETs and FET 506 , which is controlled by control voltage V ON 516 , is a single FET. So when control voltage V 1 528 is at its maximum value and control voltage V 2 530 is at zero volts, 101 FETs are providing gain. If FET 502 and each device within FET 504 have a transconductance of G m , the total transconductance is 101 G m .
To begin decreasing the power delivered to load 514 , control voltage V 2 530 is increased. When control voltage V 2 530 reaches its maximum value, current I RF + 526 splits up among FETs 502 , 504 and 506 . Because FETs 504 and 506 are, in actuality, each 100 FETs, the current division is such that 100/201 of current I RF + 526 flows in a path 520 through FET 504 , another 100/201 of the current flows in a path 522 through FET 506 and 1/201 of the current flows in a path 518 through FET 502 .
Because of the symmetry of CMOS VGA circuit 500 , similar current division occurs for I RF − 534 . This means that 101/201 of the current now flows through load 514 . The other 100/201 of the current now flows in path 522 through FET 506 and in path 536 through FET 508 . This means that when control voltage V 2 530 reaches its maximum value, the current delivered to load 514 is about ½ of the maximum possible current. This change in current corresponds to a change in power of about 6 dB because the power is proportional to the square of the current.
As shown in FIG. 4 , output changes of much more than 6 dB are needed, but changing control voltage V 2 530 from zero to its maximum value causes a change of only about 6 dB. Further changes in power output require changing control voltage V 1 528 .
For CMOS VGA circuit 500 , changing control voltage V 2 530 from zero to its maximum value results in a decrease in output power of only 6 dB. Further decreases in output power require a decrease in control voltage V 1 528 . To decrease power by much more than 6 dB, most of the decrease in output power will have to come from decreasing control voltage V 1 528 .
If all of the FETs in CMOS VGA circuit 500 were turned OFF, I 0 + 524 , I RF + 526 , I 0 − 532 and I RF − 534 would, in theory, all be zero. Because the FETs in CMOS VGA circuit 500 are not ideal, their leakage will cause this minimum value to be nonzero and not well-controlled. Because this current is not well-controlled, V ON 516 is always kept at its maximum value. The minimum value of I 0 + 524 then occurs when FET 504 is turned OFF and FET 506 is fully ON. Similarly, the minimum value of I 0 − 532 occurs when FET 510 is turned OFF and FET 508 is fully ON. Since FETs 502 and 512 are single FETs but FETs 506 and 508 are, in fact, each an arrangement of 100 FETs, the minimum possible current through load 514 is 1/101 of the maximum possible current. The minimum possible current of about 1/100 of the maximum possible current corresponds to a power difference, from a maximum to a minimum power, of about 40 dB.
In CMOS VGA circuit 500 , varying control voltage V 2 530 through its entire range results in a power change of 6 dB. As discussed above, the total power range of the circuit is about 40 dB. Of this 40 dB, about 34 dB comes from varying control voltage V 1 528 . This means that a linear relationship, like one shown in FIG. 4 , cannot be obtained with CMOS VGA circuit 500 .
FIG. 2 shows a conventional transmitter and FIG. 5 shows a conventional method of controlling the gain when an amplifier in the conventional transmitter is not implemented with bipolar transistors and is, for example, implemented in CMOS. As explained above, voltage-to-current and current-to-voltage conversions in transmitter 200 cause many undesirable results. Also as explained above, the conventional gain control method of FIG. 5 does not give the desired gain curve shown in FIG. 4 .
What is needed is a transmitter that eliminates the undesirable results caused by voltage-to-current and current-to-voltage conversions and that also provides a gain curve similar to the one shown in FIG. 4 .
BRIEF SUMMARY
It is an object of the present invention to provide a transmitter that eliminates the undesirable results caused by voltage-to-current and current-to-voltage conversions and that also provides a gain curve similar to the one shown in FIG. 4 .
In accordance with an aspect of the present invention, a current canceling CMOS variable gain amplifier includes a first leg and a second leg. The first leg has a first input line, a first output line, a first ON transistor, a first control transistor and a first subtracting transistor. The second leg has a second input line, a second output line, a second ON transistor, a second control transistor and a second subtracting transistor. The second input line can provide a second input current. The second output line can provide a second output current. The first input line is arranged to provide a first input current to each of the first ON transistor, the first control transistor and the first subtracting transistor. The second input line is arranged to provide a second input current to each of the second ON transistor, the second control transistor and the second subtracting transistor. The first output line is in electrical connection with each of the first ON transistor, the first control transistor and the second subtracting transistor. The second output line is in electrical connection with each of said second ON transistor, said second control transistor and said first subtracting transistor.
Additional objects, advantages and novel features of the invention are set forth in part in the description which follows, 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.
BRIEF SUMMARY OF THE DRAWINGS
The accompanying drawings, which are incorporated in and form a part of the specification, illustrate an exemplary embodiment of the present invention and, together with the description, serve to explain the principles of the invention. In the drawings:
FIG. 1 illustrates a conceptual view of a modulator;
FIG. 2 illustrates a conventional integrated circuit transmitter with QAM:
FIG. 3 illustrates a conventional system 300 used to control the gain of a VGA in a conventional transmitter;
FIG. 4 is a graph, wherein the x-axis corresponds to linear control voltage and the y-axis is the gain of the VGA of FIG. 3 ;
FIG. 5 illustrates an example of a CMOS VGA circuit using a conventional method for controlling power output;
FIG. 6 illustrates an example quadrature modulation transmitter in accordance with an aspect of the present invention;
FIG. 7 illustrates an example embodiment of a CMOS transmitter in accordance with an aspect of the present invention;
FIG. 8 illustrates an example current canceling VGA 800 in accordance with an aspect of the present invention;
FIG. 9 a graph, wherein the x-axis corresponds to linear control voltage and the y-axis is the output power of VGA 800 ; and
FIG. 10 illustrates an example system for controlling a current canceling VGA, in accordance with an aspect of the present invention, to make to make the output power in dBm linearly proportional to a control code.
DETAILED DESCRIPTION
In accordance with an aspect of the present invention, an example CMOS transmitter eliminates the problems caused by voltage-to-current and current-to-voltage conversions. The example CMOS transmitter also solves the problem of providing a linear relationship between power output in dBm and control voltage when bipolar transistors are not used to provide linear to exponential conversion of the control voltage.
The example CMOS transmitter avoids the problems caused by voltage-to-current and current-to-voltage conversion because the example CMOS transmitter has no such conversions. In accordance with an aspect of the present invention, all of the circuit portions within the modulator as well as the first amplifier in an example CMOS transmitter accept current as input and provide current as output. Accordingly, in an example CMOS transmitter in accordance with an aspect of the present invention, no voltage-to-current conversions and no current-to-voltage conversions are required between functional blocks.
The problem of providing a linear relationship between output power in dBm and control voltage is solved by using a current canceling amplifier that provides a curve similar to the one shown in FIG. 4 . Because the curve is similar, but not identical, to the shape shown in FIG. 4 , a lookup table may be used to provide the needed corrections.
Aspects of the present invention will now be further described with reference to FIGS. 6-10 .
FIG. 6 illustrates an example quadrature modulation transmitter 600 in accordance with an aspect of the present invention.
Transmitter 600 includes a first amplification stage 602 , a transformer 625 , a transconductance amplifier 626 , a VGA 628 , an impedance matching device 660 and a load 662 . First amplification stage 602 includes a DAC 606 , a DAC 616 , a low pass filter 608 , a low pass filter 618 , a mixer 610 , a mixer 620 and a VGA 624 .
First amplification stage 602 is arranged to receive data 607 , data 609 , a local oscillator signal 611 and a local oscillator signal 621 . First amplification stage 602 is additionally arranged to output a current 637 . Transformer 625 is arranged to receive current 637 and output a voltage 638 . Transformer 625 provides impedance matching between VGA 624 and transconductance amplifier 626 . Transconductance amplifier 626 is arranged to receive voltage 638 and to output a current 640 . VGA 628 is arranged to receive current 640 and to output a current 642 . Impedance matching device 660 is arranged to receive current 642 and to output a voltage 644 . Load 662 is arranged to receive voltage 644 .
Within first amplification stage 602 , DAC 606 is arranged to receive data 607 from an external source and to output a current 630 . Low pass filter 608 is arranged to receive current 630 from DAC 606 and to output a current 632 . Mixer 610 is arranged to receive current 632 from low pass filter 608 . Mixer 610 is also arranged to receive local oscillator signal 611 from an external source and to output a current 634 .
Within first amplification stage 602 , DAC 616 is arranged to receive data 609 from an external source and to output a current 631 . Low pass filter 618 is arranged to receive current 631 from DAC 616 and to output a current 633 . Mixer 620 is arranged to receive current 633 from low pass filter 618 . Mixer 620 is also arranged to receive local oscillator signal 621 from an external source and to output a current 636 .
VGA 624 is arranged to receive a current 622 as a combination of current 634 and current 636 and to output current 638 .
The operation of transmitter 600 will now be explained with additional reference to FIG. 2 .
In operation, local oscillator signal 611 and local oscillator signal 621 are both at a carrier frequency at which transmitter 600 will be operating. Local oscillator signal 611 is in quadrature with local oscillator signal 621 , meaning that local oscillator signals 611 and 621 have the same frequency but differ in phase by 90°. DAC 606 , low pass filter 608 and mixer 610 make up an in-phase leg of transmitter 600 . DAC 616 , low pass filter 618 and mixer 620 make up a quadrature leg of transmitter 600 . A current path 604 exists through the in-phase leg of transmitter 600 , and a current path 614 exists through the quadrature leg of transmitter 600 .
DAC 606 converts data 607 from digital to analog data as current 630 . Low pass filter 608 removes high frequency noise from current 630 . Mixer 610 combines the filtered current 632 with local oscillator signal 611 to create current 634 , which is local oscillator signal 611 modulated by data 607 .
DAC 616 converts data 609 data from digital to analog data as current 631 . Low pass filter 618 removes high frequency noise from current 631 . Mixer 620 combines current 633 with local oscillator signal 621 to create current 636 , which is local oscillator signal 611 modulated by data 609 .
Current 634 and current 636 combine to create current 622 . VGA 624 amplifies/attenuates current 622 and outputs current 638 . Transformer 625 matches the output impedance of VGA 624 to the input impedance of transconductance amplifier 626 . Transconductance amplifier 626 accepts voltage 638 and outputs current 640 . VGA 628 amplifies/attenuates current 640 and outputs current 642 . Impedance matching device 660 matches the output impedance of VGA 628 to the impedance of load 662 . Impedance matching device 660 also matches the balanced output of VGA 628 to the unbalanced load 662 .
If the output of VGA 624 is sufficient, transconductance amplifier 626 and VGA 628 can be eliminated, in which case current 638 from VGA 624 would be connected directly to impedance matching device 660 .
Impedance matching device 660 and load 662 are of conventional design, and they serve the same function as impedance matching device 228 and load 230 , respectively, of transmitter 200 .
DACs 606 and 616 provide a current output with no internal voltage-to-current conversions and no internal current-to-voltage conversions. Low pass filter 608 and low pass filter 618 are designed to accept current inputs. There are no voltage-to-current conversions and no current-to-voltage conversions between DAC 606 and low pass filter 608 . Similarly, there are no voltage-to-current conversions and no current-to-voltage conversions between DAC 616 and low pass filter 618 . Further, low pass filter 608 and low pass filter 618 are designed to provide a current output with no internal voltage-to-current conversions and no internal current-to-voltage conversions. Mixers 610 and 620 are designed to accept current as input and provide current as output with no internal voltage-to-current conversions and no internal current-to-voltage conversions.
In FIG. 6 , current path 604 shows the path of current flowing with no voltage-to-current conversions and no current-to-voltage conversions in the in-phase leg of transmitter 600 . Current path 614 shows the path of current flowing with no voltage-to-current conversions and no current-to-voltage conversions in the quadrature leg of transmitter 600 . There are no voltage-to-current conversions and no current-to-voltage conversions along either of these paths. There are no voltage-to-current conversions and no current-to-voltage conversions within DACs 606 and 616 , low pass filters 608 and 618 , mixers 610 and 620 and VGA 624 .
Because there are no voltage-to-current conversions and no current-to-voltage conversions within DACs 606 and 616 , low pass filters 608 and 618 , mixers 610 and 620 and VGA 624 , the problems associated with transmitter 200 caused by such conversions do not occur in transmitter 600 .
VGA 624 and VGA 628 may be, in an example embodiment, implemented as current canceling VGAs. Such an implementation addresses the mentioned gain control problems of CMOS VGA circuit 500 of FIG. 5 . Current canceling VGAs are another aspect of the present invention as will be discussed below.
FIG. 7 illustrates an example embodiment of a CMOS transmitter 700 in accordance with an aspect of the present invention. CMOS transmitter 700 is an example implementation of transmitter 600 of FIG. 6 .
As illustrated in FIG. 7 , CMOS transmitter 700 includes a DAC 702 , a low pass filter 704 , a mixer 706 , a VGA 708 , a DAC 712 , a low pass filter 714 , a mixer 716 , a current junction 735 , a current junction 739 , a transformer 710 , a transconductance amplifier 718 , a VGA 720 , a transformer 722 and a load 724 .
DAC 702 includes an FET 762 , an FET 764 , an FET 766 and an FET 768 . Low pass filter 704 includes a capacitor 770 , a capacitor 772 and a capacitor 774 . Mixer 706 includes an FET 775 , an FET 776 , an FET 777 and an FET 778 .
DAC 712 includes an FET 782 , an FET 784 , an FET 786 and an FET 788 . Low pass filter 714 includes a capacitor 790 , a capacitor 792 and a capacitor 794 . Mixer 716 includes an FET 795 , an FET 796 , an FET 797 and an FET 798 .
VGA 708 includes an FET 741 , an FET 743 , an FET 745 and an FET 747 . Transconductance amplifier 718 includes an FET 751 and an FET 753 . VGA 720 includes an FET 719 , an FET 721 , an FET 723 and an FET 725 .
Within DAC 702 , FET 762 and FET 764 are arranged as a current source that provides a current at the drain of FET 764 . FET 766 is arranged to receive current from the drain of FET 764 at its source and to receive a stream of digital data 730 at its gate. FET 768 is arranged to receive current from the drain of FET 764 at its source and to receive a stream of digital data 731 at its gate. Because this is a balanced system, digital data 731 has an opposite polarity of digital data 730 . FET 766 is arranged to supply an analog current at its drain, and FET 768 is arranged to supply an analog current at its drain.
Within low pass filter 704 , capacitor 770 , capacitor 772 and capacitor 774 are arranged to receive current from FET 766 and FET 768 and to supply current to the sources of FETs 775 , 776 , 778 and 779 .
Within mixer 706 , FETs 775 and 776 are arranged to receive at their sources a current 703 from low pass filter 704 . FETs 777 and 778 are arranged to receive at their sources a current 705 from low pass filter 704 . FET 775 is arranged to receive a local oscillator signal 707 at its gate, and FET 778 is arranged to receive local oscillator signal 707 at its gate. Local oscillator signal 707 is a balanced signal, and the gates of FETs 776 and 777 are arranged to receive a signal 709 , which is 180° out of phase from local oscillator signal 707 . The drains of FETs 775 and 777 are arranged to provide a current 732 . The drains of FETs 776 and 778 are arranged to provide a current 738 .
Within DAC 712 , FET 782 and FET 784 are arranged as a current source that provides a current at the drain of FET 784 . FET 788 is arranged to receive current from the drain of FET 784 at its source and to receive a stream of digital data 740 at its gate. FET 786 is arranged to receive current from the drain of FET 784 at its source and to receive a stream of digital data 791 at its gate. Because this is a balanced system, digital data 791 has an opposite polarity of digital data 740 . FET 788 is arranged to supply an analog current at its drain, and FET 786 is arranged to supply an analog current at its drain.
Within low pass filter 714 , capacitor 790 , capacitor 792 and capacitor 794 are arranged to receive current from FET 788 and FET 786 and to supply current to the sources of FETs 798 , 797 , 796 and 795 .
Within mixer 716 , FETs 795 and 796 are arranged to receive at their sources a current 713 from low pass filter 714 . FETs 797 and 798 are arranged to receive at their sources a current 715 from low pass filter 714 . FET 795 is arranged to receive a local oscillator signal 717 at its gate, and FET 798 is arranged to receive a local oscillator signal 717 at its gate. Local oscillator signal 717 is a balanced signal, and the gates of FETs 796 and 797 are arranged to receive a signal 711 , which is a 180° out of phase version of local oscillator signal 717 . The drains of FETs 795 and 797 are arranged to together provide a current 734 . The drains of FETs 796 and 798 are arranged to together provide a current 742 . Local oscillator signals 707 and 717 are 90° out of phase. Local oscillator signals 709 and 711 are 90° out of phase.
Current junction 735 is arranged to receive current 732 and current 734 and to output a current 736 . Current junction 739 is arranged to receive current 738 and current 742 and to output a current 744 .
Within VGA 708 , FETs 741 and 743 are arranged to receive current 744 . FETs 745 and 747 are arranged to receive current 736 . FETs 741 and 745 are arranged to together output a current 746 . FETs 743 and 747 are arranged to together output a current 748 . With this arrangement, VGA 708 is a current canceling VGA. Current canceling VGAs are an aspect of the present invention and will be discussed in more detail later.
Transformer 710 is arranged to receive at its primary currents 746 and 748 , which are balanced with respect to a ground node 749 . Transformer 710 is also arranged, by correctly configuring its' turns ratio, to output at its secondary winding, a voltage 750 and a voltage 752 , which voltages are measured with respect to ground node 749 . Transformer 710 turns ratio provides impedance matching between VGA 708 and transconductance amplifier 718 .
Within transconductance amplifier 718 , FET 751 is arranged to receive voltage 750 and to output a current 754 . FET 753 is arranged to receive voltage 752 and to output a current 756 .
Within VGA 720 , FETs 719 and 721 are arranged to receive current 754 . FETs 723 and 725 are arranged to receive current 756 . FETs 719 and 723 are arranged to together output a current 758 . FETs 721 and 725 are arranged to together output a current 760 . With this arrangement, VGA 720 is another current canceling VGA, which will be discussed in more detail later.
Transformer 722 is arranged, by properly configuring its' turns ratio, to provide impedance matching between VGA 720 and load 724 . Transformer 722 also provides balanced to unbalanced signal conversion for the single ended load 724 .
Operation of CMOS transmitter 700 will now be described in greater detail.
DAC 702 converts digital data 730 from digital to analog, and DAC 712 converts digital data 740 from digital to analog. DACs 702 and 712 are designed to convert a digital input directly to a differential output current. Low pass filter 704 removes high frequency noise from the output of DAC 702 . Low pass filter 714 performs a similar function for DAC 712 . Low pass filters 704 and 714 operate in the current domain and perform no voltage-to-current conversions and no current-to-voltage conversions.
Mixer 706 will now be explained with additional reference to FIGS. 1 and 2 . Mixer 706 combines data, in the form of currents at 703 and 705 , with local oscillator signal 707 . Currents 703 and 705 together correspond to information signal 102 of modulator 100 of FIG. 1 and to signal 234 of transmitter 200 of FIG. 2 . Local oscillator signal 707 corresponds to carrier signal 104 in modulator 100 of FIG. 1 and to carrier signal 236 of transmitter 200 of FIG. 2 . Currents at 732 and 738 together correspond to modulated carrier signal 106 of modulator 100 of FIG. 1 and to signal 238 of transmitter 200 of FIG. 2 .
As previously explained, local oscillator signal 707 is a balanced signal, and signal 717 is the quadrature version of local oscillator signal 707 . When local oscillator signal 707 is positive with respect ground node 749 , signal 709 is negative with respect to ground node 749 , and vice versa. When local oscillator signal 707 is positive with respect to ground node 749 , FETs 775 and 778 are OFF, and FETs 776 and 777 are ON. In this case, current 732 is the same as current 705 , and current 738 is the same as current 703 . When local oscillator signal 707 is negative with respect to ground node 749 , FETs 776 and 777 are OFF, and FETs 775 and 778 are ON. In this case, current 732 is the same as current 703 , and current 738 is the same as current 705 .
When local oscillator signal 707 is positive with respect to ground node 749 , the differential current flowing out of mixer 706 is the differential input current multiplied by one (1). When local oscillator signal 707 is negative with respect to ground node 749 , the differential current flowing out of mixer 706 is the differential input current multiplied by negative one (−1). For a square wave local oscillator signal 707 , these multiplications are equivalent to multiplying the input of mixer 706 by local oscillator signal 707 times a constant.
Mixer 706 is known as a Gilbert cell mixer. Mixer 706 corresponds to multiplier 210 of transmitter 200 of FIG. 2 . Other embodiments may include other known mixers, non-limiting examples of which include a current commutating mixer and an I/Q rejection mixer.
Mixer 716 performs the same function as mixer 706 except that its data is in the form of currents 713 and 715 and its oscillator signal is 717 .
Current junctions 735 and 739 together correspond to adder 222 in FIG. 2 .
Currents 746 and 748 are the output of VGA 708 . Currents 746 and 748 flow into ground node 749 , completing current flow from the V DD node 727 to ground node 749 . In accordance with an aspect of the present invention, current flows from V DD node 727 to ground node 749 with no intervening current-to-voltage conversions and with no intervening voltage-to-current conversions.
Transformer 722 converts the output of VGA 720 from balanced to unbalanced with respect to ground and matches the impedance of load 724 .
If the output power of VGA 708 is sufficient for a particular application, transformer 710 could be used to match the output of VGA 708 to a load. In that case, transconductance 718 , VGA 720 and transformer 722 would not be needed.
In the embodiment shown in FIG. 7 , DAC 702 , DAC 712 , mixer 706 and mixer 716 are all implemented in PMOS, whereas VGA 708 is implemented in NMOS. In another example embodiment, DAC 702 , DAC 712 , mixer 706 and mixer 716 may all be implemented in NMOS, whereas VGA 708 would be implemented in PMOS. In such an embodiment, ground node 749 in FIG. 7 would be changed to a V DD node, and V DD node 727 would be changed to a ground node. Other combinations of NMOS and PMOS devices can also be utilized to implement DAC 702 and DAC 712 , LPF 704 and 714 , mixer 706 and 716 and VGA 708 .
FIG. 7 is an example embodiment or a CMOS transmitter in accordance with an aspect of the present invention. Other example embodiments of a transmitter in accordance with the present invention may comprise other semiconducting devices, non-limiting examples of which include bipolar devices and gallium arsenide devices.
A portion of the example embodiment shown in FIG. 7 will be described with additional reference to FIG. 6 .
DACs 702 and 712 correspond to DACs 606 and 616 respectively. Low pass filters 704 and 714 correspond to low pass filters 608 and 618 , respectively. Mixers 706 and 716 correspond to mixers 610 and 620 respectively. VGA 708 corresponds to VGA 624 . DACs 702 and 712 , low pass filters 704 and 714 , mixers 706 and 716 and VGA 708 together correspond to first amplification stage 602 . There are no current-to-voltage conversions and no voltage-to-current conversions in the circuits that correspond to first amplification stage 602 .
Data 607 and data 609 correspond to digital data 730 and digital data 740 , respectively. Local oscillator signal 611 and local oscillator signal 621 correspond to local oscillator signal 707 and local oscillator signal 717 , respectively.
Current flowing along current path 604 in FIG. 6 corresponds to current flowing from FET source 701 to current junction 735 and current junction 739 . Current flowing along current path 614 in FIG. 6 corresponds to current flowing from FET source 703 to current junction 735 and current junction 739 .
In CMOS transmitter 700 , VGA 708 and VGA 720 are implemented as current canceling VGAs. Current canceling VGAs provide better gain control linearity than conventional VGAs such as CMOS VGA circuit 500 of FIG. 5 .
FIG. 8 illustrates an example current canceling VGA 800 in accordance with an aspect of the present invention.
As illustrated in FIG. 8 , current canceling VGA 800 includes an FET 802 , an FET 804 , an FET 806 , an FET 808 , an FET 810 and an FET 812 . FIG. 8 also shows a center-tapped load 814 . Load 814 is not pan of current canceling VGA 800 .
FET 802 is arranged to receive a control voltage V ON 816 at its gate and to output a current 818 at its drain. FET 804 is arranged to receive a control voltage V 1 828 at its gate and to output a current 820 at its drain. FET 806 is arranged to receive a control voltage V 2 830 at its gate and to output a current 822 at its drain. The sources of FETs 802 , 804 and 806 are arranged to receive current from a current I RF + 826 .
FET 808 is arranged to receive a control voltage V 2 830 at its gate and to output a current 823 at its drain. FET 810 is arranged to receive a control voltage V 1 828 at its gate and to output a current 821 at its drain. FET 812 is arranged to receive a control voltage V ON 816 at its gate and to output a current 819 at its drain. The sources of FETs 808 , 810 and 812 are arranged to receive current from a current I RF − 834 .
Load 814 is arranged to receive a current I 0 + 824 and a current I 0 − 832 . Current I 0 + 824 and current I 0 − 832 both flow into the V DD node 836 .
Control voltage V ON 816 is connected to the gates of FETs 802 and 812 . Control voltage V 1 828 is connected to the gates of FETs 804 and 810 , and control voltage V 2 830 is connected to the gates of FETs 806 and 808 . Although FETs 802 , 804 , 806 , 808 , 810 and 812 are each illustrated as a single FET, FETs 804 , 806 , 808 and 810 are, in fact, each an arrangement of 50 FETs, whereas each of FETs 802 and 812 are, in fact, an arrangement of 51 FETs. The actual number of FETs depend on the desired total gain control range, however the difference of number of FETs between 802 and 804 , and between 802 and 806 is 1. The difference of number of FETs between 812 and 810 , and between 812 and 808 is 1.
When voltage V 1 828 is at its maximum value and voltage V 2 830 is at zero volts, no current flows through FETs 806 and 808 , and current I 0 + 824 is equal to current I RF + 826 . Similarly, when voltage V 1 828 is at its maximum value and voltage V 2 830 is at zero volts, current I 0 − 832 is equal to current I RF − 834 . When voltage V 1 828 is maximum and voltage V 2 830 is zero, as just described, current canceling VGA 800 provides maximum power to load 814 .
To begin decreasing the power delivered to load 814 , voltage V 2 830 is increased. As voltage V 2 830 is increased from zero, current I 0 + 824 originates from FETs 802 , 804 and 808 . Current I 0 − 832 originates in a similar way from FETs 806 , 810 and 812 . Because FET 808 provides cross coupling between current I 0 + 824 and current I RF − 834 , a negative current is added to current I 0 + 824 . Because FET 802 is actually 51 FETs and because FETs 804 , 806 and 808 are actually 50 FETs, the current division and redirection is such that when V 2 830 reaches its maximum value, which is equal to the maximum value of voltage V 1 828 , current I 0 + 824 is 51/151 of current I RF + 826 . Similarly, current I 0 − 832 is 51/151 of current I RF − 834 . This means that when voltage V 1 828 and voltage V 2 830 are equal and are at their maximum values, the change in current I 0 + 824 and current I 0 − 832 corresponds to change in power of 10(log(51/151)) dB, which is a change of approximately 9.5 dB because power is proportional to the square of the current.
One of the advantages of current canceling VGA 800 will now be described with additional reference to FIGS. 4 and 5 .
CMOS VGA circuit 500 of FIG. 5 provides a change of power output of 6 dB when control voltage V 1 528 is at its maximum value and control voltage V 2 530 is changed from zero to its maximum, wherein further changes in power output require changing control voltage V 1 528 . This means that a linear relationship, like the one shown in FIG. 4 , between control voltage and output power in dBm cannot be obtained with CMOS VGA circuit 500 .
On the other hand, current canceling VGA 800 provides a change of power output of 9.5 dB when voltage V 1 828 is at its maximum and voltage V 2 830 is changed from zero to its maximum, wherein further changes in power output require changing voltage V 1 828 . Although current canceling VGA 800 does not provide a perfectly linear curve like the one shown in FIG. 4 , it provides an improved curve when compared to CMOS VGA circuit 500 of FIG. 5 . As will be described later, the output power versus control voltage curve for current canceling VGA 800 can be further improved, in accordance with another aspect of the present invention.
Another advantage of current canceling VGA 800 will now be described with reference to CMOS VGA circuit 500 of FIG. 5 .
In CMOS VGA circuit 500 , FETs 502 , 504 and 506 include a total of 201 FETs and provide a maximum transconductance of 101 G m . For current canceling VGA 800 , FETs 802 , 804 and 806 include a total of only 151 FETs and provide a maximum transconductance of (51+50)G m , which equals 101 G m . Current canceling VGA 800 uses fewer devices than CMOS VGA circuit 500 , but provides the same maximum transconductance. The decreased number of devices decreases capacitance, power dissipation and physical size of the circuit.
In both VGA 800 and VGA 500 , the minimum current that flows through loads 814 and 514 is 1/101 on input current I RF + or I RF − . The total gain control range (dynamic range) is 40 dB.
FIG. 9 will now be described with additional reference to current canceling VGA 800 .
FIG. 9 is a graph, wherein the x-axis corresponds to control voltages V 2 830 and V 1 828 and the y-axis corresponds to the power output of current canceling VGA 800 in units of dBm. The right half 902 of the x-axis shows control codes when an 8-bit DAC is used to control V 2 830 . The left half 904 of the x-axis shows control codes when an 8-bit DAC is used to control V 1 828 . The control codes on right half 902 increase from right to left, whereas the control codes on left half 904 increase from left to right.
FIG. 9 shows that the shape of the curve of output power in dBm as a function of control codes for VGA 800 is similar, but not identical, to the desired curve shape shown in FIG. 4 . A system for controlling VGA 800 to make FIG. 9 linear like FIG. 4 is an aspect of the present invention and will now be discussed.
FIG. 10 illustrates an example system 1000 for controlling a current canceling VGA 800 in accordance with an aspect of the present invention, to make the output power in dBm linearly proportional to a control code.
As illustrated in FIG. 10 , system 1000 includes a lookup table (LUT) 1002 , a DAC 1004 and a VGA 1006 .
Lookup table 1002 is arranged to receive a VGA control word 1008 and to output a control code 1010 . DAC 1004 is arranged to receive control code 1010 and to output a control voltage 1012 . Current canceling VGA 1006 is arranged to receive control voltage 1012 and a signal 1014 and to output a signal 1016 .
In accordance with an aspect of the present invention, because voltage V 1 828 is adjusted only when voltage V 2 830 is at its minimum, only one DAC is required for the control of these two signals. DAC 1004 is switched between voltage V 2 830 and voltage V 1 828 depending on which one is being adjusted.
The operation of system 1000 will now be explained with additional reference to FIGS. 4 , 8 and 9 .
FIG. 9 shows output power in dBm as a function of control voltage for current canceling VGA 800 . The right half 902 of FIG. 9 shows, going from right to left, the decrease in output power as V 2 830 is increased from zero to its maximum value while V 1 828 is at its maximum. The left half 904 of FIG. 9 shows, going from right to left, the decrease in output power as V 1 828 is decreased from its maximum value to zero while V 2 830 is zero. Look up table 1002 converts input control word 1008 into control code 1010 to create a linear output power in dBm as a function of control code curve similar to FIG. 4 . If, for example, DAC 1004 is an 8-bit DAC, lookup table 1002 would have 512 entries, 256 for use when DAC 1004 is controlling V 2 830 and 256 others for use when DAC 1004 is controlling V 1 828 . In this example, input control word 1008 would include nine (9) bits, one bit to select between V 2 830 and V 1 828 and eight (8) bits for the control code for the selected control voltage.
A CMOS transmitter in accordance with the present invention eliminates several problems in prior art implementations.
In prior art implementations, inherent current-to-voltage conversions and voltage-to-current conversions introduce undesirable nonlinearities. These conversions also cause undesirable increases in power consumption and in noise, and these conversions have the undesirable side effect of increasing the number of devices needed in an integrated circuit. A CMOS transmitter in accordance with the present invention eliminates these problems by operating in the current mode and thereby eliminating all current-to-voltage and all voltage-to-current conversions.
Furthermore, prior art VGAs that did not use bipolar junction transistors could not provide a linear power output per in dBm as a function of control code curve for controlling power output. A current cancelling VGA in accordance with the present invention solves this problem.
The foregoing description of various preferred embodiments of the invention have 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, and obviously many modifications and variations are possible in light of the above teaching. The exemplary embodiments, as described above, were chosen and described in order to best explain the principles of the invention and its practical application to thereby enable others skilled in the 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 scope of the invention be defined by the claims appended hereto.
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A current canceling CMOS variable gain amplifier includes a first leg and a second leg. The first leg has a first input line, a first output line, a first ON transistor, a first control transistor and a first subtracting transistor. The second leg has a second input line, a second output line, a second ON transistor, a second control transistor and a second subtracting transistor. The second input line can provide a second input current. The second output line can provide a second output current. The first input line is arranged to provide a first input current to each of the first ON transistor, the first control transistor and the first subtracting transistor. The second input line is arranged to provide a second input current to each of the second ON transistor, the second control transistor and the second subtracting transistor. The first output line is in electrical connection with each of the first ON transistor, the first control transistor and the second subtracting transistor. The second output line is in electrical connection with each of the second ON transistor, the second control transistor and the first subtracting transistor.
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This invention relates to a method of improving the quality of a product made from or made in contact with a body of vitreous silica.
In one aspect, the invention relates to a method of making an improved vitreous silica product, such as a crucible, a tube or a plate, having a reduced impurity content, and to a product produced by the method.
The invention also relates to an improved method for using a vitreous silica vessel for the high temperature processing of a material contained therein. Particularly valuable uses of this method of the invention are found in the treatment of molten semiconductor materials in a vitreous silica crucible (e.g. in the drawing of a single crystal of silicon).
DISCUSSION OF PRIOR ART
An arc moulded crucible (AMC) is normally produced by fusing a powder material under the influence of an electrical arc while the powder material (e.g. quartz powder) is held in place in a rotating mould (e.g. of water cooled metal) by centrifugal force, with or without the application of a vacuum via the mould wall(s).
A vitreous silica crucible is commonly used to contain a melt from which a single crystal is drawn. In the case of semiconductor materials, high purity is of vital importance and much effort has been, and is still being, given to avoiding impurity contamination of the melt during the crystal pulling operation. The crucible is one potential source of such contamination.
In the case of the pulling of a silicon crystal from melt in a vitreous silica crucible, alkali impurities may transfer to the molten silicon from the wall(s) of the crucible and a variety of different, often time-consuming and otherwise expensive, procedures have been proposed for the purification of the starting material used for a vitreous silica crucible to reduce the alkali impurities therein.
It has now been discovered that a reduced impurity content in material fused in a vitreous silica crucible can be obtained by the simple expedient of applying a polarising potential across the wall(s) of the crucible, at least while the latter is at a temperature in excess of 700° C., for such a period and with such a polarity that ions of the or each impurity will migrate across the wall(s) of the crucible away from the inside surface thereof.
Impurity migration can be effected when the crucible is first fused from the starting material and/or by applying a correctly polarised potential across the wall(s) of the crucible when it contains melt. In the case of alkali impurity ions (which so far appear to be the impurities most easily removed from the crucible wall/melt interface) a voltage with positive polarity on the inside and negative polarity on the outside of the crucible will be required. Voltages between 1 and 2000 volts appear to be effective over the temperatures and times typical for pulling a single crystal from a bath of molten semiconductor material. The migration rate is a function of temperature and applied voltage and preferably the temperature of the inside surface of the crucible wall(s) is in excess of 900° C.
The crucible wall(s) is/are not a significant barrier to the diffusion of impurities (e.g. Na, K or Li) which in the absence of an electrolysing potential may migrate through the wall(s) from the crucible holder, and which in the presence of an electrolysing potential can migrate into the wall(s) from melt in the crucible.
Although the invention is thought to have an important commercial impact in the areas of the high temperature production of products from vitreous silica vessels and the manufacture of such vessels with reduced alkali impurity content, it will be appreciated that vitreous silica tubing whose impurity content has been reduced by electrolysis can have other useful applications than as an intermediary in the manufacture of a vitreous silica vessel.
Hence it should be appreciated that the invention also extends to the production of improved vitreous silica products (e.g. tubing) either by a one-stage process in which an ion-migrating potential is applied across the product during manufacture, or by a two-stage process in which an ion-migrating potential is applied across a heated billet prior to further processing (e.g. drawing) with or without further electrolysis during that further processing.
Once ion migration in a vitreous silica body has been achieved using the principles described herein, it would often be desirable to remove any ion-enhanced region from the body so that even if back diffusion should subsequently occur, there will be a net improvement in impurity content of the vitreous silica body.
SUMMARY OF THE INVENTION
Thus, in its broadest aspect, the present invention relates to a method of improving the quality of a product made from, or made in contact with, a body of vitreous silica, which is characterised in that impurity ions are made to migrate away from one boundary surface of the body towards an opposite boundary surface thereof by applying a polarising potential across the boundary surfaces of the body while the body is maintained at a temperature above 700° C.
The polarising potential is typically poled to make alkali metal ions migrate away from the said one boundary surface. Typical temperatures are in the range 800° to 2000° C., typical process times are from one to a few tens of hours at the lower end of the range and a few minutes to an hour at higher temperatures and typical polarising potentials from a few tens of volts to a few kilovolts.
The method can be used to make tubing and other vitreous silica products of improved purity.
It is thus feasible to electrolyse tubing during fusing to cause migration of ions away from one wall surface and then to produce the desired product either from a powder starting material taken from ion-depleted regions of the tubing (e.g. by grinding off the ion-rich region(s)), or directly from the electrolysed tubing using ion-depleted regions for the inside walls. Preferably polarising potential should be reapplied every time the wall material is heated above about 750° C. and certainly above 900° C. if some back-diffusion is not to occur but if a sufficient impurity depletion has been achieved during manufacture of the product or its starting material, such back-diffusion may not matter. In practice, however, since electrolysing a vitreous silica vessel during use is neither difficult nor expensive to achieve, it could be employed even where a low-alkali-impurity content vitreous silica material was used in its manufacture.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will now be more fully described with reference to the accompanying drawings, in which:
FIG. 1 is a schematic indication of the invention applied to improve single crystal semiconductor material drawn from a vitreous silica crucible and as described in the following Examples 10 to 12,
FIG. 2 shows a vitreous silica crucible whose purity has been improved by the method of the invention which is being processed as described in the following Examples 1 and 2,
FIG. 3 shows how a vitreous silica crucible can be made in accordance with the invention in the manner described in the following Examples 3 and 4,
FIGS. 4 and 5 show a crucible being made in the manner described, respectively, in the following Examples 5 to 7 and Example 8, and
FIG. 6 shows how the quality of vitreous silica tubing can be improved as described in the following
DESCRIPTION OF PREFERRED EMBODIMENTS
FIG. 1 shows, purely schematically, a single crystal 10 of silicon being drawn from a bath 12 of molten silicon contained in a vitreous silica arc moulded crucible 14. In the usual way, the crucible 14 is contained within a graphite susceptor 16 heated by an induction coil (not shown) and the crystal 10 depends from a seed crystal 10a which has been slowly drawn upwards out of the surface of the bath 12.
A d.c. potential is applied between the seed crystal 10a and the susceptor 16 with the polarity as shown, this potential being maintained throughout the pulling operation. The magnitude of the applied potential can vary from a minimum which is sufficient to overcome contact resistances and ionisation potentials and establish a current of a few microamps, to a maximum where the high voltage causes arcing or other problems. In practice, a potential of between a few volts and a few hundred volts would normally be used. FIG. 1 is further discussed in the following Examples 10 to 13.
EXAMPLES OF THE INVENTION
Example 1
(see FIG. 2)
A previously manufactured crucible 20 of 300 mm diameter with a 6 mm wall thickness was heated to 1050° C. in nitrogen. An internal electrodes 21, consisting of high purity carbon powder loosely filled into the crucible 20, and an external electrode was provided by a graphite holder 22 into which the crucible 20 fitted loosely. The gap between the holder 22 and the crucible 20 was filled with high purity carbon powder 23. Care was taken to ensure excess carbon powder did not cause short circuits. The upper 10 mm of the crucible protruded above the holder and internal powder fill to act as a barrier to surface tracking by the applied voltage. The holder was made the negative electrode.
The voltage was applied gradually on the crucible reaching 1050° C. to keep the electrolysing current below 50 mA. After 40 minutes, the full voltage of 2.5 KV could be applied.
Electrolysis continued for 4 hours, then the temperature was allowed to drop to room temperature with the full voltage still applied.
Analysis of the crucible material after this treatment is shown in Table 1 as AMC 3.
Example 2
A second crucible was treated as in Example 1 except that the polarising voltage was switched off at 800° C. as the crucible was cooling following electrolysis at 1050° C.
Analysis of the crucible is shown in Table 1 as AMC 4. From the results it can be seen that back diffusion of the alkali ions is insignificant below 800° C.
Example 3
(see FIG. 3)
A further crucible 30 was heated directly in a spinning graphite mould 31 using an oxy propane flame 32 so that the crucible softened and came into intimate contact with the mould. The mould was made negative and the burner positive using a voltage of 3.8 KV. The high electrical impedance of the flame greatly reduced the voltage available for electrolysis but some improvement was measured as can be seen from the figures shown in Table 1 as AMC 10. The time of electrolysis was 5 minutes.
Example 4
A further crucible was treated as in Example 3 except that an R.F. induction plasma replaced the flame 32. The analysis of this treated crucible is shown as AMC 14 in Table 1.
Example 5
(see FIG. 4)
A crucible 40 was manufactured using the spinning mould method to hold high purity quartz powder in position. Heating was with an arc 41 and the mould 42 was of water-cooled metal. An electrolysing voltage of 10 KV was applied for the final 2 minutes of heating using the arc 41 as the positive electrode and the mould 42 as the negative electrode. The analytical result is shown as AMC 21 in Table 1.
Example 6
A crucible was manufactured as for Example 5 except that an uncooled graphite mould was used in place of the water-cooled mould 42. The analytical result is shown in Table 1 as AMC 23. The improved result when compared with Example 5 is believed to be due to the higher electrical resistance of the quartz powder kept cold by the water-cooled mould in Example 5, reducing the voltage available for electrolysis.
Example 7
A crucible was manufactured as for Example 6 except that during fusion a partial vacuum of 8-7 kPa was applied between the mould 42 and the forming crucible 40 via a pipe 45.
The analytical result is shown as AMC 31. The lower impurity content in this case is believed to be due to partial ionisation of the gas in the gap between the mould and the forming crucible due to the partial vacuum and this ionised gas acting as the negative electrode.
TABLE 1______________________________________ Noted impurity in ppm by weightCrucible Position Surface Na.sub.2 O K.sub.2 O Li.sub.2 O______________________________________AMC3 Side Inner <0.1 <0.1 <0.1 Wall Outer 1.5 4.2 3.3 Base Inner 0.2 0.2 0.2 Wall Outer 1.6 3.3 2.8AMC4 Side Inner <0.1 <0.1 <0.1 Wall Outer 2.5 2.0 4.4 Base Inner <0.1 <0.1 <0.1 Wall Outer 0.1 0.2 0.3AMC10 Mean Inner 0.9 1.5 0.2 Value Outer 2.2 2.0 2.0AMC14 Mean Inner <0.1 <0.1 <0.1 Value Outer 0.2 0.4 0.2AMC21 Mean Inner 0.9 1.2 0.2 Value Outer 1.4 2.5 2.0AMC23 Mean Inner 0.2 1.3 <0.1 Value Outer 0.9 2.5 0.5AMC31 Mean Inner <0.1 0.2 <0.1 Value Outer 0.1 0.4 0.1AMC33 Mean Inner <0.1 <0.1 <0.1 Value Outer 0.2 0.5 <0.1Starting Material for AMC 3, 4, 5.6 5.4 3.810, 14Starting Material for AMC 21, 23, 1.4 2.5 3.231______________________________________
Example 8
(see FIG. 5)
A manufactured crucible 50 was placed over a closely fitting graphite internal mould 51 and heated externally with an oxy-propane ribbon burner 52. The temperature reached on the surface of the crucible was sufficient to remelt it.
A potential difference was applied between the burner 52 and the mould 51 of 4.5 KV. The mould was rotated at 1 RPM so that the flame swept over all the crucible. The mould was the positive electrode. During the processing it was noted that the flame was coloured by the ions being electrolysed from the crucible.
An additional result of the heating was that the outside of the crucible became glazed.
The analytical results appear in Table 1 as AMC 33.
Example 9
(see FIG. 6)
A cylindrical pipe 60 of fused quartz with an external diameter of 200 mm, a length of 1500 mm and a wall thickness of 25 mm was subject to electrolysis across the wall with a potential difference of 10 KV.
An inner electrode 61 (anode) was made by coating the inner surface with a layer approximately 2 mm thick consisting of a paste of low alkali titanium dioxide (British Titan Products Ltd.--Grade A-HR) and a proprietary low alkali silica sol (Nalfloc Ltd.--"Nalcoag 1034A"). Connection to this electrode was made with a nickel chromium alloy band 62 which was a spring fit in the bore.
An outer electrode (cathode) consisted of a layer 63 approximately 2 mm thick coating the whole outer surface except the ends and consisting of a paste of ferric oxide and a silica sol. Connection to this electrode was made with an open pitch coil 64 of nickel chromium heat resisting wire.
Electrolysis was carried out at 1050° C. On reaching temperature, the voltage was gradually increased so as to avoid exceeding the current limitation of the power supply (100 ma). Maximum voltage of 10 KV was reached after 8 hours 40 minutes.
Electrolysis continued for 30 hours, when the furnace was allowed to cool naturally. The voltage was switched off when the pipe had cooled to 800° C.
The results of the electrolysis are shown as B4 in Table 2.
Example 10
The cylindrical pipe of fused quartz from Example 9 was machined externally to remove 1 mm from the bore and 3 mm from the external surface leaving a wall thickness of 21 mm. After cleaning with detergent and dilute hydrofluoric acid it was reheated in a graphite resistance furnace and drawn into tubing. Some of this tubing was reworked with flames on a glass working lathe to the form of a crucible. The analysis of the crucible is shown in Table 2 as Cl.
TABLE 2______________________________________ Impurity concentration in ppm by weightSurface Na.sub.2 O K.sub.2 O Li.sub.2 O______________________________________B4 Inner <0.1 <0.1 <0.1 Centre <0.1 <0.1 <0.1 Outer 13.9 4.8 8.0Tube from B4 0.1 0.1 <0.1C1 Inner <0.1 <0.1 <0.1 Outer <0.1 0.1 <0.1Starting Material 8.8 4.3 4.4for B4______________________________________
Example 11
(see FIG. 1)
A single crystal "puller" was modified to allow a voltage to be applied between the silicon single crystal 10a of FIG. 1 and the graphite susceptor 16 during that growing operation which was carried out in Argon at 1 atmosphere gauge. After the crystal 10 had achieved the desired diameter, a voltage of 50-1000 V was applied between the crystal (positive) and the susceptor (negative). The voltage was derived from a current limited source of 0.010A.
Results for the silicon crystal 10 are shown in Table 3.
Example 12
A single crystal was grown as for Example 11 except that a sub-atmospheric pressure of 15-20 torr was used in the puller. The maximum polarising voltage was limited to 200 V.
The results are shown in Table 3 (S2).
Example 13
A single crystal was grown as for Example 11 except that a coating of glassy carbon (obtained by the pyrolysis of propane diluted with Argon) had been made on the outside of the quartz crucible before use in order to improve the electrical contact between the crucible and the susceptor.
The results are shown in Table 3 (S3).
TABLE 3______________________________________Resistivity of Single Crystalohm-cm P.Type Silicon______________________________________Without polarizing Crystal Shoulder 145Voltage Crystal end 115With polarizing S1 Crystal Shoulder 500Voltage Crystal end 300 S2 Crystal Shoulder 850 Crystal end 600 S3 Crystal Shoulder 1250 Crystal end 1050______________________________________
From the foregoing Examples, it will be appreciated that the electrolysing temperature and time conditions are related one to the other and to the wall thickness across which the polarising potential is applied. In summary, these process conditions are preferably that the body is maintained for a time of at least 1 hour/mm wall thickness in the temperature range 800°-1200° C. and at least 1 min/mm thickness in the temperature range 1201°-2000° C. The effective polarising potential applied across the boundary surfaces preferably exceeds 10 V/mm thickness but not 1 KV/mm thickness.
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An improved quality vitreous silica boby and/or improved quality product made at high temperature in a vitreous silica vessel is/are obtained by applying a polarizing potential across the boundary surfaces of the vitreous silica body or vessel to cause migration of impurity ions away from one of the boundary surfaces thereof. Single crystal silicon (10) of reduced alkali content is drawn from melt (12) in a vitreous silica crucible (14) with a polarizing voltage applied across the wall of the crucible.
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CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This case claims priority of U.S. Provisional Patent Application U.S. 60/908,679, which is incorporated by reference herein.
FIELD OF THE INVENTION
[0002] The present invention relates to weapon systems in general, and, more particularly, to a system for testing a weapons system.
BACKGROUND OF THE INVENTION
[0003] The Shkval is a high-speed, supercavitating, rocket-propelled torpedo developed by Russia. It was designed to be a rapid-reaction defense against U.S. submarines undetected by sonar. It can also be used as a countermeasure to an incoming torpedo, forcing the hostile projectile to abruptly change course and possibly break its guidance wires.
[0004] The solid-rocket propelled torpedo achieves a high velocity of 250 knots (288 mph) by producing an envelope of supercavitating bubbles from its nose and skin, which coat the entire weapon surface in a thin layer of gas. This causes the metal skin of the weapon to avoid contact with the water, significantly reducing drag and friction.
[0005] The Shkval is fired from the standard 533-mm torpedo tube at a depth of up to 328 ft (100 m). The rocket-powered torpedo exits the tube at 50 knots (93 kmh) and then ignites the rocket motor, propelling the weapon to speeds four to five times faster than other conventional torpedoes. The weapon reportedly has an 80 percent kill probability at a range of 7,655 yd (7,000 m).
[0006] The torpedo is guided by an autopilot rather than by a homing head as on most torpedoes. Reportedly, there is a homing version of the Shkval that starts at the higher speed but slows and enters a search mode.
[0007] Notwithstanding its defense-motivated origins, the Shkval is potentially a very significant offensive threat. To defeat such a torpedo, a surface ship deck-launched anti-torpedo must be capable of (1) brief but stable flight, (2) entering the water at a low grazing angle, and (3) sustaining a supercavitating running mode under water.
[0008] There are no torpedo vehicles available that are capable of approaching the Shkval's speed. It is not possible, therefore, to access the feasibility of any anti-Shkval weapon system to a reasonable level of confidence. Consequently, there is a need for a test set-up that can act as a surrogate for an attacking Shkval torpedo, so that an anti-Shkval weapon system can be developed and tested.
SUMMARY OF THE INVENTION
[0009] The present invention provides a test system that is capable of evaluating the effectiveness of an anti-Shkval weapon system or other weapons system designed to defeat an incoming, very fast-moving, underwater munition.
[0010] In the illustrative embodiment, an extremely large tubular sheath is inflated underwater. The sheath, which is effectively a “balloon,” is maintained at a depth and inclination that is appropriate for an incoming torpedo. An inert projectile is flown/propelled inside the sheath at the speed of a Shkval torpedo—250 knots.
[0011] The sheath must be large enough in diameter to accommodate at least a minimal amount of projectile maneuvering. And the sheath must be long enough to provide for an expected amount of travel based on the projectile's speed and the time it is likely to take for the defensive system to “acquire” and destroy the projectile. A sheath having a diameter (inflated) that is in the range of about 5 to 15 meters and a length (inflated) that is in the range of about 50 to 500 meters should be adequate, as a function of the specific aspects of the anti-weapon that are being tested.
[0012] The sheath must of course be sufficiently pressurized to resist water pressure, as a function of its depth under water. In some embodiments in which the projectile is missile (i.e., self-powered), the sheath is reinforced at the region where the missile initially fires, to accommodate the heat and erosive exhaust is generated.
[0013] The sheath, projectile, or both can be appropriately painted to simulate the reflectivity of a Shkval, as influenced by the supercavitating bubbles that would be shrouding it in its supercavitating running mode. Alternatively, the air can be colored or misted for the same purpose.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 depicts a diagram of a test system in accordance with the illustrative embodiment of the present invention.
[0015] FIG. 2 depicts a further embodiment of the test system of FIG. 1 , wherein floats and/or weights are used to adjust the inclination of the sheath.
[0016] FIG. 3 depicts an example in which a proposed anti-supercavitating torpedo weapon system is tested via the test system of FIG. 1 .
[0017] FIG. 4 depicts a block diagram of the weapon system of FIG. 2 .
DETAILED DESCRIPTION
[0018] FIG. 1 depicts a diagram of test system 100 in accordance with the illustrative embodiment of the present invention. The test system can be located in a large and sufficiently deep pond or tank, or in a natural water way, as appropriate. In the illustrative embodiment, test system 100 is used to test a ship-mounted high-speed-torpedo defense system, such as system 122 , which is located on vessel 120 .
[0019] In the illustrative embodiment, system 100 includes gas supply line 102 , sheath 110 , and inert projectile 112 . Gas supply line 102 is partially submerged; gas intake 104 is above the water line and gas discharge 108 is below the water line. Gas supply line 102 is supported in an appropriate fashion (e.g., from above, from below, etc.).
[0020] Gas intake 104 of the gas supply line receives flow 118 of gas (e.g., air, nitrogen, etc.). In some embodiments, the gas as supplied is appropriately pressurized. In some other embodiments, gas supply line 102 includes an inline gas compressor (not shown). The inline gas compressor draws gas (e.g., air, etc.) into gas intake 104 , compresses the gas, and then directs it toward gas discharge 108 . Some embodiments will receive gas from a pressurized source and then pressurize it further via an inline compressor.
[0021] Control valve 106 controls flow 118 of gas through supply line 102 . In some embodiments, control valve 106 is remotely controlled. Control valve 106 is meant to be representative of what is more likely to be an arrangement of valves (e.g., check valves, flow control valves, etc.) for controlling the flow of gas through supply line 102 .
[0022] Sheath 110 is coupled, via a gas-tight connection, to gas discharge 108 of gas supply line 102 . The sheath is a non-porous bag, typically flexible, that is suitable for inflation with a gas. Effectively, sheath 110 is a very long, tube-shaped balloon.
[0023] Flow 118 of compressed gas exits gas discharge 108 of gas supply line 102 and inflates sheath 110 .
[0024] Supported within sheath 110 is projectile 112 . The projectile is inert; in other words, it does not carry a munitions payload. Projectile 112 is supported by support 114 , which in the illustrative embodiment, is coupled to gas supply line 102 .
[0025] Projectile 112 can be self-powered (e.g., a missile, etc.), or it can be ejected (e.g., launched via an auxiliary power source). To the extent that projectile 112 is self-powered, shield 116 is advantageously employed to protect sheath 110 from hot exhaust gases. Furthermore, in some embodiments, sheath 110 is reinforced and appropriately lined, proximal to the launch location, with a heat- and abrasion-resistant material. Once launched, projectile 112 proceeds through sheath 110 .
[0026] Sheath 110 must be large enough in diameter to accommodate at least a minimal amount of projectile maneuvering. To that end, diameter D of the inflated sheath is typically in a range of about 5 to 15 meters. Furthermore, the sheath must be long enough to provide for an expected amount of travel based on the speed of projectile 112 speed and the time it is likely to take for the defensive system to “acquire” and, as appropriate, destroy the projectile. Length L of the sheath is typically in a range of about 50 to 500 meters, as a function of the specific aspects of the anti-weapon that are being tested (e.g., target acquisition or target acquisition and neutralization, etc.).
[0027] To serve as a useful test bed, sheath 110 should be situated underwater at an appropriate depth. That depth will typically be 100 meters or less.
[0028] In most instances, a torpedo will be fired from a depth that is greater than that of its target. In other words, the torpedo will rise from its launch depth to a target depth. As a consequence, it is advantageous to control the inclination of sheath 110 to permit projectile 112 to follow a typically inclined trajectory.
[0029] Sheath 110 is depicted in a horizontal attitude in FIG. 1 . Actually, it's free end would typically rise higher in the water than the fixed end (located at discharge 108 ), since the sheath is filled with gas and is less dense than the water. The inclination of sheath 110 can be controlled using floats 224 and weights 225 , as depicted in FIG. 2 . Any desired inclination/declination can be provided with an appropriate selection of floats and weights.
[0030] In some embodiments, ribs (not depicted), are positioned along the length of sheath 110 . The ribs provide rigidity to inflated sheath 110 to help maintain an elongated cylindrical shape.
[0031] FIG. 3 depicts test system 100 being used to test ship-mounted high-speed-torpedo defense system 122 aboard vessel 120 . The high-speed torpedo-defense system integrates several conventional technologies via a command and control system. The control system coordinates the activities of these various technologies to acquire and destroy a rocket-propelled or other high-speed torpedo.
[0032] Torpedo defense system 122 , which is not a part of test system 100 , includes command and control system 326 , SONAR 328 , LIDAR 330 , and weapons system 334 . See also FIG. 4 , depicting the flow of communications and information between the various elements of high-speed torpedo defense system.
[0033] Command and control system (“CCS”) 326 coordinates the activities of and provides processing for the constituent systems (SONAR 328 , LIDAR 330 , and weapons system 332 ). More particularly, CCS 326 coordinates initial detection, via SONAR, which provides the torpedo's bearing to about +/− one degree. The CCS also coordinates hand-off to LIDAR 330 for high resolution bearing and ranging. Furthermore, CCS 326 coordinates weapons system 332 , under the control of LIDAR 330 .
[0034] CCS 326 comprises one or more processors. Due to the rapid response time required to acquire and destroy a high-speed torpedo (i.e., about 5 seconds), CCS 326 operates with relative autonomy. CCS 326 does require operator interaction for initialization, system troubleshooting, training, and support. In some embodiments, CCS 326 includes redundant hardware that is disposed in several locations aboard ship to improve the survivability of system 122 .
[0035] SONAR system 328 comprises conventional passive SONAR, active SONAR, or both. In some embodiments, the SONAR system is modified to provide higher-frequency detection for increased resolution by reducing the spacing of hydrophones in the SONAR array. CCS 326 supports the operation of SONAR 328 by performing data processing for passive SONAR (e.g., beamforming, classification, track, etc.) to develop the initial detection and bearing information relative to the frame of reference for the other systems (e.g., LIDAR 330 and weapons 332 . CCS 326 also controls active SONAR with information for waveforms, source level, and other acoustic parameters that are required for proper operation.
[0036] LIDAR 330 is a conventional light detection and ranging system for ranging and tracking. It typically utilizes a high-power pulsed laser system. CCS 326 provides LIDAR 330 with control data for operation and aiming. Further, CCS 326 takes the optical data from LIDAR receivers and develops high-resolution track information relative to the gun frame of reference.
[0037] Weapons system 332 comprises one or more rotary guns (e.g., a gatling gun, etc.) or reciprocating guns. In some embodiments, the gun fires low-grazing angle, supercavitating projectiles, such as projectile 336 . CCS 326 develops gun control information that will properly lead the gun to fire projectiles where the target will be when the projectiles travel to that volume. The software for CCS 326 accounts for any translation impacts due to ship movement, including mast motions, gun recoils, gun inertial, ship movement due to weather, etc.
[0038] In operation of test system 100 to evaluate the efficacy of high-speed torpedo defense system 122 , projectile 112 is launched/fired. SONAR 328 of defense system 122 detects (or, if ineffective, does not detect) the launch of projectile 112 and determines bearing and approximate range. Bearing accuracy is about +/− one degree.
[0039] SONAR 328 hands over bearing and range to LIDAR 330 , which places an initial range “gate” in a fixed position at approximately a standoff range. In an actual encounter, the gate would be at about 1000 yards. But in the context of test system 100 , the gate is suitably adjusted to meet the limitations (reduced size scale) of test system 100 .
[0040] When projectile 112 breaches the gate, LIDAR 330 initiates tracking of the torpedo, determining its position in angle-angle range space. LIDAR 330 then hands this information over to weapons system 332 . More particularly, the information from LIDAR 330 is used to position the guns to an initial pointing position, positioning the gun at the exact firing point to provide a high probability of projectile impact with the incoming projectile 112 .
[0041] In an actual attack scenario, weapons system 332 would open fire at about 500 meters. This distance is suitably adjusted for the reduced size scale of test system 100 . In some embodiments, projectiles are not fired from weapons system 332 toward test system 100 . In some other embodiments, projectiles 334 are fired from weapons system 332 , which will damage or destroy sheath 110 . In some embodiments, projectiles 334 from the deck launcher are preferably cavity-running, delayed-ignition, high-explosive projectiles. The projectiles are designed to enter the water at low grazing angles, and enter into a cavity-running or super-cavitation mode. On impact with the torpedo, a delayed ignition system detonates a high-explosive fill.
[0042] The performance of the high-speed-torpedo defense system is evaluated based on target acquisition time and other performance measures.
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A test system that is capable of evaluating the effectiveness of a weapons system designed to defeat an incoming, fast-moving, underwater munition is disclosed. In the illustrative embodiment, an extremely large tubular sheath is inflated underwater. The sheath is maintained at a depth and inclination that is appropriate for an incoming torpedo. An inert projectile is launched or flown inside the sheath at a speed that is consistent with the speed of munition that the weapons system is intended to defeat.
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CROSS-REFERENCE TO RELATED APPLICATION
This application claims priority to co-pending U.S. Provisional Patent Application No. 62/259,859, filed on Nov. 25, 2015, the entire contents of which is hereby incorporated by reference.
FIELD
The present invention relates to mobile (e.g., wheeled) devices and, more particularly, to a handle assembly for such devices.
SUMMARY
Tool storage devices are often used to transport tools and accessories between and around worksites. As such, the devices may include wheels and a telescoping handle assembly to allow for convenient transportation of the tool storage devices. However, durability is a factor because the devices may be used in various terrain and weather conditions on the worksite. Due to these conditions and the generally rugged use, the devices sustain various shocks and impacts that are transmitted from the device (e.g., the wheels) through the telescoping handle assembly. These impacts and shocks can lead to early failure of the mechanism that secures the telescoping handle assembly in an extended position.
In one independent aspect, a telescoping handle assembly for a mobile device, such as a wheeled device, a storage device, etc. may be provided. The handle assembly may generally include a first handle section; a second handle section telescopingly arranged relative to the first handle section; and a latch assembly fixed to one of the first handle section and the second handle section and selectively engageable with the other of the first handle section and the second handle section. The latch assembly may include a latch body positioned between the first handle section and the second handle section, and a shock-absorbing mount positioned between the latch body and the one of the first handle section and the second handle section.
In another independent aspect, a wheeled mobile device may generally include a frame; a wheel assembly supporting the frame; and a telescoping handle assembly including a first handle section, a second handle section telescopingly arranged relative to the first handle section, and a latch assembly fixed to one of the first handle section and the second handle section and selectively engageable with the other of the first handle section and the second handle section. The latch assembly may include a latch body positioned between the first handle section and the second handle section, and a shock-absorbing mount positioned between the latch body and the one of the first handle section and the second handle section.
In yet another independent aspect, a method of assembling a telescoping handle assembly for a mobile device may be provided. The method may generally include fixing a latch body of a latch assembly to one of a first handle section and a second handle section; positioning a shock-absorbing mount between the latch body and the one of the first handle section and the second handle section; and inserting the one of the first handle section and the second handle section into the other of the first handle section and the second handle section in a telescoping arrangement with the latch assembly positioned in the other of the first handle section and the second handle section.
Other independent features and independent aspects of the invention will become apparent by consideration of the following detailed description, claims and accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a mobile device, such as a wheeled storage device (e.g., a portable rolling tool bag).
FIG. 2 is an enlarged exploded view of a handle assembly for the device shown in FIG. 1 .
FIG. 3 is a perspective view of a latch assembly for the handle assembly shown in FIG. 2 .
FIG. 3A is a perspective view of a bushing of the latch assembly shown in FIG. 3
FIG. 4 is an enlarged cross-sectional view of the handle assembly of FIG. 2 taken generally along line 4 - 4 in FIG. 1 .
FIG. 5 is an enlarged cross-sectional view of the handle assembly of FIG. 2 taken generally along line 5 - 5 in FIG. 1 .
FIG. 6 is a perspective view of a prior art latch assembly.
DETAILED DESCRIPTION
Before any independent embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other independent embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting.
Use of “including” and “comprising” and variations thereof as used herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Use of “consisting of” and variations thereof as used herein is meant to encompass only the items listed thereafter and equivalents thereof.
FIG. 1 illustrates a mobile device 10 , such as a portable rolling tool bag, movable between and around various locations (e.g., work sites, construction sites, garages, etc.). Exemplary devices are shown and described in U.S. Patent Application Publication No. 2016/0023349, filed Jul. 17, 2015, the entire contents of which is hereby incorporated by reference. In other constructions (not shown), the device 10 may include a tool box, a storage device, a suitcase, a trolley, a dolly, a hand truck, a cart, a wheel barrow, a stroller, a wheel chair, a bed, a table, etc.
The device 10 generally includes a frame 14 supported by one or more wheels 18 . As a tool bag, the illustrated device 10 also includes a body 22 defining a storage compartment (not shown), capable of supporting and storing tools, accessories, materials, etc., in an organized manner. A handle assembly 26 is connected to the frame 14 and facilitates maneuvering of the device 10 .
The handle assembly 26 includes a handle member 30 connected to an end of one or more support arms 34 (two in the illustrated construction) adjustably supported by the frame 14 . Each support arm 34 includes a number of telescoping arm sections 38 a , 38 b . . . 38 n (three in the illustrated construction). The arm sections 38 a - 38 c are adjustable between an extended position (see FIGS. 1-2 ) and a retracted position (not shown) to adjust the position of the handle member 30 relative to the frame 14 and the body 22 .
Each arm section 38 is an elongated hollow member with a substantially uniform cross-section extending along its length. Each outer arm section (e.g., the arm section 38 b ) has a cross-section sized to slidingly receive an associated inner arm section (e.g., the arm section 38 a ) having a relatively smaller concentric cross-section. In the illustrated embodiment, each arm section 38 has a generally rectangular cross-section defined by a pair of short walls 47 and a pair of long walls 48 . In other embodiments (not shown), the arm sections 38 may have any shape cross-section with corresponding walls.
With reference to FIGS. 1-2 , a latch assembly 42 is provided between adjacent arm sections 38 to selectively and releasably hold the arm sections 38 in the extended position. In the illustrated construction, each outer arm section (e.g., the arm section 38 b ) defines a recess (e.g., an opening 46 ) proximate its upper end 39 , and each inner arm section (e.g., the arm section 38 a ) supports a projection 50 proximate its lower end 40 . Each projection 50 is selectively engageable in an associated opening 46 to hold the adjacent arm sections (e.g., the arm sections 38 a , 38 b ) in a selected relative position. In the illustrated embodiment, the opening 46 arranged to receive the projection 50 is defined in one of the short walls 47 .
Each projection 50 (see FIG. 3 ) is movably supported on a lower portion 55 of a latch body 54 . The lower portion 55 of the latch body 54 is sized to be slidingly received in the outer arm section 38 (e.g., the arm section 38 b ) and is too large to be received in the inner arm section 38 (e.g., the arm section 38 a ). An actuating member 58 is operable to move the projection 50 relative to the body 54 between a projected, latching position (see FIG. 3 ) and a retracted, release position (see FIG. 5 ). An actuator (not shown) is operable by the user to retract and disengage each projection 50 from its associated recess 46 so that the arm sections 38 can be retracted and the handle member 30 lowered.
The body 54 is fixed to the arm section (e.g., the arm section 38 a ), for example, by a rivet 62 ( FIGS. 2 and 4 ), or a similar fastener, such as a pin, etc. In the illustrated construction, the rivet 62 extends through a pair of openings 64 defined in the long walls 48 of the arm section 38 adjacent the lower end 40 of the arm section 38 and an opening 66 in an upper portion 56 of the body 54 aligned with the openings 64 (as shown in FIG. 4 ). In the illustrated embodiment, one end of the rivet 62 has a pre-formed head and the other end of the rivet 62 is deformed to secure the rivet 62 from being axially removed from the opening 66 in the body 54 .
The upper portion 56 of the body 54 is sized to be received in the lower end 40 of the inner arm section 38 (e.g., the arm section 38 a ), as shown in FIGS. 4-5 . The lower portion 55 of the body 54 inhibits insertion of the upper portion 56 of the body 54 into the arm section 38 to a position in which the openings 64 in the long walls 48 do not align with the opening 66 in the body 54 .
A similar handle assembly including a latch assembly is illustrated and described in U.S. Pat. No. 6,339,863, issued Jan. 22, 2002, and in U.S. Pat. No. 6,619,448, issued Sep. 16, 2003, the entire contents of both of which are hereby incorporated by reference.
In existing handle assemblies, a failure mode is a fracture around the rivet which causes the handle assembly to fail at 17 to 22 miles in a fatigue cyclic loading “life test”. Such failure is likely to occur even with improved materials, geometry of an existing latch assembly (see FIG. 6 ).
As shown in FIGS. 2-5 , the illustrated latch assembly 42 incorporates a shock-absorbing mount 70 ( FIG. 3A ) operable to absorb, dampen, limit, reduce, etc. a shock or impact between the frame 14 and the handle member 30 (e.g., between the body 54 and the walls 47 , 48 of the adjacent arm section 38 ). The mount 70 may increase or contribute to an increase in the life, strength, durability, etc. of the handle assembly 26 to, for example, at least 30 miles or more in the fatigue cyclic loading “life test”.
In the illustrated construction, the mount 70 includes a bushing 74 received in the opening 66 and is positioned between the body 54 and the rivet 62 . The bushing 74 is formed of shock-absorbing material, such as, for example, urethane (e.g., thermoplastic polyurethane (TPU)), soft plastic, rubber, etc. The material, material characteristics, structure, etc. of the bushing 74 can be adjusted based on, for example, the desired shock-absorbing characteristics.
As illustrated, the bushing 74 is formed as a discrete or separate part and is inserted into the opening 66 . In other constructions (not shown), the bushing 74 may be formed with the body 54 , for example, in a multi-shot molding process for the body 54 . After the bushing 74 is assembled with the body 54 , the rivet 62 is inserted.
In operation with the illustrated mount 70 , an impact or shock on the device 10 (e.g., on the wheels 18 as the device 10 is rolled across an uneven surface) is transmitted through the frame 14 to the outer arm section (e.g., the arm section 38 b ), through the walls 47 , 48 of the arm section 38 b to the body 54 . The shock is absorbed or dampened by the bushing 74 before reaching the rivet 62 and, through the rivet 62 , the inner arm section (e.g., the arm section 38 a ) and the handle member 30 . An impact or shock on the handle member 30 is likewise absorbed or dampened by the bushing 74 before reaching the walls 47 , 48 of the outer arm section 38 b . Providing a mount 70 between each of the adjacent arm sections 38 sequentially reduces the magnitude of the impact or shock as it passes through each of the mounts 70 .
In other constructions (not shown), in addition to or as an alternative to the illustrated mount 70 , a shock-absorbing mount may be provided at one or more other locations between components in the force-transmitting path between the frame 14 and the handle member 30 . For example, a shock-absorbing bushing, plate, other structure, etc., may be provided between the long walls 48 of the outer arm section 38 b and the end of the rivet 62 . In another example, a shock-absorbing mount may be provided between the frame 14 and the adjacent arm section 38 c.
In the illustrated construction, the mount 70 has the form of the hollow cylindrical (e.g., tubular) bushing 74 received in the circular opening 66 and receiving the cylindrical rivet 62 . In other constructions, the mount 70 may have a different form factor. For example, with a square or rectangular pin (not shown), the mount 70 may include a pad (e.g., a flat isolation pad) engaging between the pin and the associated support structure (e.g., the opening in the latch body, the opening in the wall of the arm section, etc.).
In the illustrated construction, a shock-absorbing mount 70 is provided between each adjacent arm section 38 of each support arm 34 of the handle assembly 26 . Accordingly, each additional connection and corresponding mount 70 increases the impact or shock reduction capability. In other constructions (not shown), a shock-absorbing mount 70 may be provided between only selected adjacent arm sections (e.g., between only the arm sections 38 b , 38 c closest to the frame 14 ).
One or more independent features and/or independent advantages of the invention may be set forth in the claims.
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A telescoping handle assembly, a mobile device, and a method of assembling a telescoping handle assembly for a mobile device. The handle assembly may include a first handle section, and a second handle section telescopingly arranged relative to the first handle section. The handle assembly may further include a latch assembly fixed to one of the first handle section and the second handle section and selectively engageable with the other of the first handle section and the second handle section. The latch assembly may include a latch body positioned between the first handle section and the second handle section and a shock-absorbing mount positioned between the latch body and the one of the first handle section and the second handle section.
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FIELD OF THE INVENTION
The field of this invention is wiper plug dropping tools and more particularly those that can sequentially launch wiper plugs using pump down plugs that are retained in the tool.
BACKGROUND OF THE INVENTION
In cementing casing or liner, wiper plugs are used to isolate the delivered cement from existing well fluids and to drive any leftover cement out of the casing or liner and through the cement shoe, which is a one way valve at the lower end of the casing or liner string. Some systems get by with only a single wiper plug. In those systems the cement is delivered on top of existing well fluids with no barrier. After the cement is delivered, the one wiper plug is dropped to displace the cement from the casing or liner and into the surrounding annulus. After that the cement shoe at the bottom of the string along with the wiper plug are simply milled up and the well is continued deeper.
In two wiper plug systems of the past, one of the concerns was to only drop one wiper plug at a time. Earlier designs of multi-plug systems used a system of two shear pins. The lower pin supported the lower wiper plug from the wiper plug above it. The upper pin held the upper plug to the tool body and was designed to shear at a higher pressure than the lower shear pin. A pump down plug seated in the tool to allow pressure to break the lower shear pin while claiming to keep the upper wiper plug in pressure balance. What was supposed to happen is that the lower pin sheared and the lower wiper plug launched. Then another pump down plug was landed to allow a net pressure force to be applied to the remaining wiper plug so that the upper shear pin that was rated higher than the lower shear pin could release. The upper wiper plug then was launched. This design is illustrated in Application WO 94/27026. The problem with this design is that if the lower shear pin didn't release when needed, pressure would build to the point of breaking the higher set upper shear pin and both wiper plugs would launch together. In other words, there was nothing to assure the upper wiper plug could not be launched with the lower wiper plug.
In an effort to address this issue U.S. Pat. No. 6,206,094 was designed to use a hydraulic system with metering capability to advance the lower wiper plug while it was still retained to the tool for a given travel distance at which point the lower wiper plug could launch. A first pump down plug allowed pressure to be applied to move a piston that moved the wiper plug at a controlled rate until it extended far enough from the tool housing to be released. A second pump down plug then allowed another piston to move at a regulated rate to advance the second wiper plug beyond the housing far enough so that it too could be launched. While this tool provided greater assurance of launching only one wiper plug at a time, it was complicated and involved rupture discs and hydraulic flow through metering orifices. It presented some risk for smooth operation as intended.
Other known wiper plug launching systems were the LFC Four Plug System offered by Baker Oil Tools that worked similarly to Application WO 94/27026 but used collets which became unsupported or sheared to trigger a release in conjunction with shear pins to hold a sleeve from moving where a collet became unsupported for release. Another similar design is U.S. Pat. No. 5,553,667 (FIG. 9). Other designs in this area include U.S. Pat. Nos. 5,803,173; 6,712,152; 6,698,513; 6,575,238; 6,681,860; 6,672,384 and 7,055,611.
What is needed and provided by the present invention is a wiper plug dropping tool that retains the pump down plugs and ensures the orderly release of the wiper plugs. It features a sleeve that is moved to release the lower wiper plug whose movement makes it possible to actually land another pump down plug in a proper position so that the release mechanism for the upper wiper plug can be actuated. Without movement of the release sleeve for the lower wiper plug there is no release of the upper wiper plug. These and other features of the present invention will be more readily apparent to those skilled in the art from a review of the description of the preferred embodiment and the associated drawings with the understanding that the full scope of the invention is measured by the claims that appear below.
SUMMARY OF THE INVENTION
A wiper plug release tool uses a first pump down plug that lands in the tool to pressurize an internal chamber to slide a sleeve that undermines a set of dogs to allow the lower wiper plug to be decoupled from support. The shifting of this sleeve cams a second set of dogs into an internal passage in the tool to act as a landing location for a second pump down plug. Landing the second pump down plug on the now extended dogs allows a net pressure to be applied to an upper piston which shifts a sleeve to release the support for the second wiper plug. The upper piston remains in pressure balance unless the second pump down plug can be landed on the dogs that only extended because the sleeve that released the lower wiper plug had shifted.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1 a - 1 d show a half section of the tool in the run in position;
FIGS. 2 a - 2 d show the tool of FIGS. 1 a - 1 d with the first pump down plug landed;
FIGS. 3 a - 3 d show the tool of FIGS. 2 a - 2 d with lower wiper plug released;
FIGS. 4 a - 4 d show the tool of FIGS. 3 a - 3 d with the second pump down plug landed and the upper wiper plug released to drop;
FIGS. 5 a - 5 d show the tool of FIGS. 4 a - 4 d with the upper release sleeve locked into the released position;
FIG. 6 is the view along lines 6 - 6 of FIG. 1 b ; and
FIGS. 7 a - 7 b show both launched wiper plugs captured in a landing collar downhole.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1 a upper mandrel 10 has a thread 12 for connecting a string, not shown. A rupture disc 14 allows diversion of pressure from internal passage 16 to the annulus 18 , for an emergency procedure that will be described below. The surrounding casing or liner that defines the annulus 18 is not shown except as 20 in FIG. 7 , which is at the lower portion of the string to be cemented and generally close to a cementing shoe (not shown).
A port 22 leads from passage 16 into chamber 24 that is defined by outer sleeve 26 . Port 28 is offset from port 22 and is isolated by sleeve 30 and its seals 32 and 34 . Sleeve 30 is secured between upper mandrel 10 and lower mandrel 52 . Seal 38 spans the gap between upper mandrel 10 and sleeve 30 . Seal 40 seals between mandrel 10 and sleeve 26 on the other side of port 22 so that when pressure is applied through passage 22 with passage 16 obstructed, as will be explained below, pressure builds up in chamber 24 to put uphole pressure on sleeve 26 . Sleeve 26 carries a snap ring 42 that is designed to snap into surface 44 after uphole movement of sleeve 26 . The snapped in position is shown if FIG. 5 a . Concluding the description of the sleeve 26 a lower segment 46 attached at thread 48 and having a lower end 50 with an internal recess 51 .
Continuing now with the upper mandrel 10 , a lower mandrel 52 is attached at thread 54 trapping a sleeve 56 in between. Seals 58 and 60 mounted to lower mandrel 52 maintain the integrity of passage 16 . Lower launch sleeve 62 is pinned to lower mandrel 52 by pins 70 . Dogs 64 are initially trapped in recess 66 in lower mandrel 52 by sleeve 56 . Dogs 64 extend through openings 68 in lower mandrel 52 . A shear pin or pins 70 retain lower launch sleeve 62 to lower mandrel 52 . Circumferentially offset from pins 70 are passages 72 that lead from passage 16 to chamber 74 . Seals 76 and 78 seal off the lower end of chamber 74 . Passage 80 leads from chamber 74 to passage 16 around sleeve 56 .
Upper wiper plug 82 has a recess 84 into which are trapped dogs 86 that pivot at 88 and have a torsion spring 90 to bias them radially inwardly when sleeves 26 and 46 move up as shown in FIG. 4 c . Upper wiper plug 82 has external fins 92 and an internal bore 94 that allows it to be mounted over lower launch sleeve 62 . A flapper 96 is designed to close the bore 94 after the upper wiper plug is launched.
Lower wiper plug 98 is similar to upper plug 82 in that it has a bore 100 that allows it to be mounted over lower launch sleeve 62 and a flapper 102 that closes bore 100 after launch of lower wiper plug 98 . External fins 104 aid in propelling the plug 98 downhole. Lock dogs 106 have a bore 108 and a pin 110 extending though it to retain them to upper wiper plug 82 . In the FIG. 1 c position, the dogs 106 are trapped into recess 112 so as to support the lower wiper plug 98 off of the upper wiper plug 82 . Lower launch sleeve 62 has a recessed surface 114 that in FIGS. 1 c and 2 c is offset from dogs 106 . A port 116 that will ultimately be used to flow cement is initially held closed by seals 118 and 120 on upper wiper plug 82 . Seal 122 on lower wiper plug 98 seals against launch sleeve 62 to allow pressure in annulus 18 to be used to propel the plug 98 after dogs 106 are undermined. Finally, sleeve 124 shown in FIG. 1 c supports upper wiper plug 82 against dogs 86 that are in turn held in recess 84 by lower segment 46 . If the running tool fails to function and release the liner wiper plugs, rupture disk 14 may be burst with applied internal pressure to serve as an emergency bypass for flow around the tool.
The major components now having been described, the operation of the tool will now be reviewed in detail. As shown in FIG. 2 d a first pump down plug 126 having a known design lands on shoulder 128 on lower launch sleeve 62 thus blocking the passage 16 . Port 116 is isolated by seals 118 and 120 at this time. As pressure is built up the first thing to happen is to break the shear pins 70 shown in two pieces in FIGS. 3 b - 3 c . Launch sleeve 62 is able to move down after shear pins 70 are broken until shouldering on ring 124 . The downward movement of lower launch sleeve 62 allows dogs 64 in windows 68 to slide in elongated recess 66 which cams dogs 64 onto surface 130 so that they the move radially inwardly, having already cleared the lower end of sleeve 56 and now supports the dogs 64 in a position where they extend into passage 16 as seen by comparing FIGS. 2 b and 3 b . At the same time, as shown in FIGS. 3 c - 3 d , the shifting of the lower launch sleeve 62 has placed recess 114 opposite dogs 106 to let them come out of lower wiper plug 98 so that it is launched and the port 116 is exposed for pumping cement behind the launched lower wiper plug 98 . As the lower wiper plug 98 leaves the lower launch sleeve 62 the flapper 102 is able to close so that the cement can then drive the plug 98 until it bumps surface 134 in the landing collar that is part of the casing or liner 20 . After bursting the rupture disk in flapper 102 , the cement continues through the landed plug and into the annulus around the casing or liner 20 in a known manner.
While the wiper plug 98 is being launched, the sleeve 26 is in pressure balance and can't move. This is because pressure in passage 16 of the tool communicates to port 22 to act on surface 136 to put an uphole force on upper sleeve 26 , see FIG. 3 b . At the same time pressure in passage 16 communicates through ports 72 and 80 to surface 138 in cavity 74 that is sealed at seals 76 and 78 . The surface 138 has the same cross-sectional area as surface 136 so that there can be no net force applied to move sleeve 26 , which is initially pinned to the upper mandrel 10 with pin or pins 140 . It is worth repeating that dogs 64 remain retracted until pump down plug 126 passes and pressure buildup causes the lower launch sleeve 62 to shift camming the dogs 64 into passage 16 when only then can they be used to catch the next pump down plug 148 as shown in FIG. 4 b.
Note that as lower launch sleeve 62 moves down it displaces fluid from cavity 142 through passages 144 and 146 as the volume of cavity 142 decreases until the lower launch sleeve's movement is stopped by hitting sleeve 124 as shown in FIG. 3 c . At this point the cement port 116 is exposed to pass cement.
When the second pump down plug 148 lands on dogs 64 the ports 72 and 80 are isolated and pressure applied to passage 16 is now exclusively directed to ports 22 . An unopposed uphole force is now applied to surface 136 to shear pins 140 . As upper sleeve 26 moves up, its lower end 46 no longer covers dogs 86 putting the upper wiper plug in position for release as shown in FIG. 4 c . The upward movement of sleeves 26 and 46 is locked in as snap ring 42 contracts against surface 44 as shown in FIG. 5 a . Applied pressure above the wiper plug fins propels the released wiper plug 82 down the casing or liner 20 until it bumps lower wiper plug 98 as shown in FIG. 7 a . The entire tool with retained pump down plugs 126 and 148 can be removed as an assembly from the well.
Those skilled in the art will now appreciate that the apparatus described above prevents the inadvertent release of two wiper plugs because not only is the upper plug release mechanism in pressure balance when the lower plug is released but the dogs 64 that allow the use of pump down plug 148 to ultimately overcome that pressure balanced configuration are held retracted making them inaccessible to the initial pump down plug 126 as it travels past to its position shown in FIG. 2 d . There is no way to accidentally release the upper wiper plug 82 before the lower plug 98 is released. In prior designs, such as FIG. 9 of U.S. Pat. No. 5,553,667 the release mechanism for the upper plug is exposed and the lower pump down plug has to travel through it where it can get lodged and result in launching both plugs. Even though the first pump down plug in that prior design is made smaller to fit through the release mechanism of the upper plug the possibility exists that the wrong shear device will fail first and release both wiper plugs. In the present invention, not only is the release mechanism in pressure balance from pressure buildup in passage 16 with pump down plug 126 landed but the movement of the first pump down plug to its landing shoulder 128 while there is no higher shoulder for that pump down plug 126 to land on that would in any way allow an unbalanced pressure force to be applied to the upper release sleeve 26 .
The above description is illustrative of the preferred embodiment and many modifications may be made by those skilled in the art without departing from the invention whose scope is to be determined from the literal and equivalent scope of the claims below.
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A wiper plug release tool uses a first pump down plug that lands in the tool to pressurize an internal chamber to slide a sleeve that undermines a set of dogs to allow the lower wiper plug to be decoupled from support. The shifting of this sleeve cams a second set of dogs into an internal passage in the tool to act as a landing location for a second pump down plug. Landing the second pump down plug on the now extended dogs allows a net pressure to be applied to an upper piston which shifts a sleeve to release the support for the second wiper plug. The upper piston remains in pressure balance unless the second pump down plug can be landed on the dogs that only extended because the sleeve that released the lower wiper plug had shifted.
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FIELD OF THE INVENTION
The present invention relates to a process for the extraction of zinc from zinc sulphide concentrates, comprising the following operations:
(a) roasting a portion of the concentrates so as to produce calcine,
(b) neutral leaching of calcine produced in the operation (a) with return spent electrolyte so as to produce a leachate which is rich in zinc and substantially iron-free, which is separated, and a zinc ferrite residue, which is separated,
(c) leaching of another portion of the concentrates and of at least a portion of the zinc ferrite residue produced in the operation (b) with a solution of sulphuric acid returning from electrolysis at 60°-95° C. in atmospheric conditions and in the presence of finely dispersed oxygen so as to produce a leachate which is rich in zinc and in iron, which is separated, and a leaching residue which is depleted in zinc, which is separated, the quantities of concentrates and of zinc ferrite which are used in this operation (c) being such that the molar ratio of the iron contained in the ferrite and the reactive sulphur contained in the concentrates is at least approximately 0.2,
(d) conditioning, preparatory to the following operation, of the leachate which is rich in zinc and in iron, produced in the operation (c),
(e) precipitation of the major portion of the iron contained in the solution conditioned in the operation (d) so as to produce a solution which is rich in zinc and depleted in iron and a ferriferous precipitate, which is separated, and
(f) introduction of the solution which is rich in zinc and depleted in iron into the neutral leaching in (b).
The following should be understood here by
"zinc sulphide concentrate": a concentrate containing, in the form of sulphides, chiefly zinc and iron and, in smaller proportions, copper, silver and/or lead;
"in atmospheric conditions": in conditions which do not require the use of autoclaves, that is to say at a pressure equal to or differing by less than 20 kPa from atmospheric pressure; and
"reactive sulphur": the sulphur present in the form of sulphide in the zinc sulphide concentrates and in the leaching residue which is rich in zinc (an expression employed later) and which can be oxidized by ferric sulphate according to the reaction:
Fe.sub.2 (SO.sub.4).sub.3 +MeS=MeSO.sub.4 +2FeSO.sub.4 +S°(I)
in which Me denotes Zn, Fe, Cu, Pb or Ag. (the reactive sulphur generally consists of all the sulphur present in the form of sulphide less the pyrite sulphur).
Using the process of the invention, a leachate which is rich in zinc and substantially iron-free, a leaching residue which is depleted in zinc and a ferriferous precipitate are therefore obtained. This leachate can be purified and subsequently electrolysed in order to extract the zinc from it. The leaching residue which is depleted in zinc, and which contains sulphur, lead sulphates, silver compounds, undissolved sulphides (pyrites) and gangue, can be subjected to an appropriate treatment in order to extract the sulphur and the valuable metals from it. The ferriferous precipitate can be stored or, when it is pure enough, can be employed as pigment or as source of iron in the steel industry.
BACKGROUND
A process similar to that as defined above is described in document EP-A-0451456. In this known process, all of the calcine produced in the operation (a) is leached in the operation (b) and all of the ferrite produced in the operation (b) is leached in the operation (c), while employing a concentrate:ferrite ratio such that approximately 15 to 20% of the trivalent iron, required for the oxidation according to reaction (I) of the reactive sulphur present in the concentrate, originates from the leaching of the ferrite according to the reaction
ZnO.Fe.sub.2 O.sub.3 +4H.sub.2 SO.sub.4 =Fe.sub.2 (SO.sub.4).sub.3 +ZnSO.sub.4 +4H.sub.2 O (II)
The remainder of the trivalent iron required for the oxidation of the reactive sulphur is obtained by the reaction
2FeSO.sub.4 +H.sub.2 SO.sub.4 +0.50.sub.2 =Fe.sub.2 (SO.sub.4).sub.3 +H.sub.2 O (III)
It is proposed to work in (c) in such a manner that the leachate which is rich in zinc and in iron has a sulphuric acid content of 10-25 g/l and an Fe 3+ content of less than 10 g/l, which is apparently unobtainable in a single leaching stage. This is why the leaching in (c) is carried out in two stages.
In the first stage, the zinc ferrite and a leaching residue which is rich in zinc, produced in the second stage, are treated with the solution of acid returning from electrolysis so as to produce a primary leachate containing 50-90 g/l of H 2 SO 4 and the leaching residue which is depleted in zinc, which are separated. No oxygen is employed in this first leaching stage, this being to make it possible to use in this stage simpler types of reactors than in the second stage. The involvement of reaction (III) is therefore not brought about in the first stage.
In the second stage, the concentrates are treated with the said primary leachate in the presence of finely dispersed oxygen so as to produce, by reactions (I) and (III), a leachate which is rich in zinc and in iron and a leaching residue which is rich in zinc. At the end of this second stage, the operation (d) is performed by adding a small quantity of fresh concentrate to the leaching pulp so as to convert ferric sulphate into ferrous sulphate by reaction (I); the operation (d) is therefore incorporated into the operation (c) and, as a result of the second leaching stage, there is obtained the leaching residue which is rich in zinc, which is separated and recycled into the first stage, and a leachate which is rich in zinc and in iron, which is already conditioned.
The operation (e) is performed by adding more concentrate to the conditioned solution and by then precipitating the iron in haematite form by oxidation in an autoclave.
This produces, on the one hand, the said solution which is rich in zinc and depleted in iron and, on the other hand, a precipitate of haematite containing a small quantity of elemental sulphur and of sulphides. This sulphur and these sulphides are subsequently separated from the haematite by flotation. The reason why the concentrate is used in the operation (e) is not given. A possible explanation could be that the acidity of the conditioned solution is too high to permit a suitable precipitation of the iron and that, because of this, concentrate is added as neutralizing agent (reactions (I) and (II)).
This known process therefore requires leaching in two stages and, since the work is carried out with a concentrates:ferrite ratio such that approximately 15 to 20% of the trivalent iron, required for the oxidation according to reaction (I) of the reactive sulphur present in the concentrate, originates from the leaching of the ferrite in accordance with reaction (II) and that oxygen is not employed in the first leaching stage, it is necessary to oxidize approximately 80 to 85% of the reactive sulphur in the second leaching stage using trivalent iron obtained by reaction (III), when a zinc leaching yield close on 100% is aimed at.
However, the Applicant has found that in these conditions the second leaching stage takes place very slowly, and this obviously constitutes a serious disadvantage. Another disadvantage of this known process lies in the fact that the operation (c) is not easy to control because the leaching yield is determined solely by the ratio of the reactive sulphur to the zinc ferrite which are introduced into the first leaching stage and because the system reacts very slowly to corrections which are made to this ratio.
Furthermore, the use of this known process in existing hydrometallurgical zinc plants would almost always entail a considerable investment for purchasing the autoclaves required for the operation (e). In fact, to the Applicant's knowledge, there are only two plants in the world which make haematite and which are therefore already equipped with such autoclaves; all the others make jarosite or goethite in atmospheric conditions and are therefore not endowed with such autoclaves.
Moreover, as in this known process all of the ferrite produced in the operation (b) is leached in (c) while employing a concentrate:ferrite ratio such that approximately 15 to 20% of the trivalent iron, required for the oxidation of the reactive sulphur, originates from the leaching of the ferrite, the installation of this process in an existing plant, the roasting capacity of which would quite logically be maintained at the existing level, would have to result at once in approximately doubling the plant capacity. However, an increase in the capacity of an existing plant which is as substantial as this all at once, which will be unavoidably accompanied with substantial investments, will not often be opportune. The process therefore lacks some degree of flexibility.
What is more, this known process produces a haematite which is soiled with sulphur and sulphides.
SUMMARY OF THE INVENTION
The objective of the present invention is to provide a process as defined above which avoids the disadvantages of the known process.
To this end, according to the invention
(1) only a portion of the calcine produced in the operation (a) is leached in the operation (b),
(2) the leaching in (c) is performed
either in a single stage, in which case the work is done so that the leachate which is rich in zinc and in iron has a sulphuric acid content of 45-75 g/l, preferably of 55-65 g/l, and an Fe 3+ content of 1-10 g/l, preferably of 2-5 g/l,
or in two stages, in which case the work is done so that the leachate which is rich in zinc and in iron has a sulphuric acid content of 10-35 g/l, preferably of 10-25 g/l, and an Fe 3+ content of 0.1-2 g/l, preferably of 0.5-1 g/l, the first stage comprising treating the zinc ferrite and a leaching residue which is rich in zinc, produced in the second stage, with the solution of sulphuric acid returning from electrolysis in the presence of finely dispersed oxygen so as to produce a primary leachate and the said leaching residue which is depleted in zinc, which are separated, and the second stage comprising treating the concentrates with the said primary leachate in the presence of finely dispersed oxygen so as to produce the said leachate which is rich in zinc and in iron and the said leaching residue which is rich in zinc, which are separated, this second stage being performed in conditions such that less than 60% and preferably less than 50% of the reactive sulphur are oxidized therein and that the leaching residue which is rich in zinc produced therein has a reactive sulphur content which is appreciably higher than that which can be oxidized in the first stage by the iron present in the ferrite,
(3) the operation (d) is performed by treating the leachate which is rich in zinc and in iron with yet another portion of the concentrates so as to return its Fe 3+ content below 5 g/l and preferably to 1-3 g/l, it being possible for this reducing treatment to be omitted when the leachate which is rich in zinc and in iron already has an Fe 3+ content of less than 5 g/l, and by treating the solution of low Fe 3+ content with another portion of the calcine produced in the operation (a), so as to return the free H 2 SO 4 content of this solution below 10 g/l and preferably to 3-5 g/l, this neutralization treatment producing, on the one hand, a zinc ferrite residue, which is separated and subsequently treated in the same way as the ferrite produced in the operation (b) and, on the other hand, a conditioned solution,
(4) the operation (e) is performed by precipitating the iron in a manner which is known per se in the form of goethite, haematite, jarosite or other compound which has suitable filterability, this being in the absence of zinc sulphide concentrate, and
(5) the leaching in the operation (c) is carried out on
either all of the ferrite residue produced in the operations (b) and (d),
or only a portion of this ferrite, in which case the remainder of this ferrite is treated separately in a manner which is known per se by hot acidic leaching, this treatment producing another leachate which is rich in zinc and in iron, and this solution is subjected to the operations (d), (e) and (f) together with the leachate which is rich in zinc and in iron, produced in the operation (c).
In fact, by leaching in the operation (b) only a portion of the calcine produced in the operation (a), it is possible to employ another portion of this calcine in the operation (d).
By performing the operation (c) as defined in (2), the leaching period is appreciably shortened, whether working in only one or in two stages, as will be demonstrated later, and this operation (c) can be easily controlled, given that the leaching yield is now determined by the quantity of oxygen used and that the system reacts promptly to corrections which are made to this parameter.
By performing the operation (d) as defined in (3), a conditioned solution is obtained in which the iron can be precipitated by any conventional oxidation and hydrolysis technique, this being done with a minimum of neutralizing agent, when goethite or jarosite is precipitated, and without it being necessary to add zinc sulphide concentrate, when haematite is precipitated.
By performing the operation (e) as defined in (4), the process of the invention can be installed in any existing hydrometallurgical zinc plant whatever, without this necessarily entailing a large investment.
Owing to its characteristic defined in (5), the process of the invention makes it possible to increase gradually the capacity of an existing plant, this being according to the needs and with an advantageous staging of the investment costs.
It is appropriate that what follows should be reported here.
Documents U.S. Pat. No. 3,976,743, U.S. Pat. No. 4,107,265 and BE-A-724214 describe processes for the treatment of zinc ferrite which make use of reactions (I) and (II), but not of reaction (III). These known processes do not make it possible to increase the capacity of the existing zinc plants producing ferrite, because all these plants already utilize reactions (I) and (II) in one way or another.
Document WO-A-91/09146 describes a process for the treatment of zinc ferrite, comprising, successively, leaching of the ferrite with acid returning from electrolysis (reaction II), partial neutralization of the residual acid by addition of ZnS concentrate in the presence of oxygen (reactions I and III), reduction of the trivalent iron by addition of concentrate (reaction I), flotation of the pulp so as to separate from it elemental sulphur and unreacted concentrate, treatment of the flotation residue with SO 2 in order further to leach the iron, the zinc and the impurities, treatment of the pulp resulting therefrom with elemental sulphur to precipitate the copper, flotation of the pulp so as to separate from it a copper sulphide concentrate, filtration of the pulp and precipitation of the iron in the resultant solution. This known process differs from the process of the invention not only in its complexity but also in the fact that reaction (II) is used before reactions (I) and (III), which lengthens the leaching period, as the Applicant has ascertained.
Documents U.S. Pat. No. 4,510,028 and EP-A-0071684 describe a process for the treatment of zinc ferrite by acidic leaching in one or two stages, in the presence of concentrate and with oxygen under pressure at 135°-175° C. (reactions I, II and III). The ferrite:concentrate ratio must be such that the zinc contained in the ferrite amounts to 5-40% and preferably to 5-20% of all the zinc contained in the ferrite and the concentrate. In contrast to the process of the invention, this known process therefore requires autoclaves for leaching the ferrite and the concentrate. Moreover, since this known process gives the best results with a low ferrite:concentrate ratio, its installation into an existing plant producing ferrite would at once enormously increase the capacity of this plant, which is not often opportune.
Document EP-A-0166710 describes a process as defined at the beginning of the present application, except that the concentrates:ferrite ratio employed in the operation (c) is not specified, that the operation (c) is performed partially under pressure and that the operation (d) is omitted. In this known process, a portion of the calcine produced in the operation (a) is leached in the operation (b) and all of the ferrite produced in the operation (b) is leached in the operation (c). The operation (c) is performed in three stages. In the first stage, the ferrite and a leaching residue which is relatively depleted in zinc, produced in the second stage, are treated with acid returning from electrolysis in the presence of oxygen and in atmospheric conditions so as to produce a primary leachate and a leaching residue which is depleted in zinc, which are separated. In the second stage, a leaching residue which is rich in zinc, produced in the first stage, and optionally concentrate, are treated with the said primary leachate in the presence of oxygen and at 120°-160° C., that is to say in an autoclave or equivalent apparatus, so as to produce a secondary leachate and the said residue which is relatively depleted in zinc, which are separated. In the third stage, concentrate is treated with the said secondary leachate in the presence of oxygen and in atmospheric conditions so as to produce a leachate which is rich in zinc and in iron and the said leaching residue which is rich in zinc, which are separated. The work is done so that the leachate which is rich in zinc and in iron has an acid content of approximately 4 to 8 g/l. This solution is subjected directly to the operation (e), which consists in precipitating the iron in the form of goethite, using as neutralizing agent the other portion of the calcine produced in (a). This known process differs from the process of the invention not only in the absence of the operation (d) and the complexity of the operation (c), the use of which additionally requires an autoclave or equivalent apparatus, but also in the fact that virtually all of the acid is exhausted in the operation (c) by the reactions (I) and (III). However, it has been found that the overall duration of the operation (c) is thus lengthened excessively. Moreover, as in this known process the other portion of the calcine produced in (a) is employed as neutralizing agent in (e), goethite containing a substantial quantity of zinc ferrite is necessarily produced, and this can be avoided in the process of the invention.
Document U.S. Pat. No. 4,004,991 describes a process for the extraction of zinc from sulphide concentrates, according to which the concentrates are leached in two stages countercurrentwise with acid returning from electrolysis in the presence of oxygen at 135°-175° C., that is to say in an autoclave. As this known process does not comprise the operations (a) and (b), the only point in common between this process and the process of the invention lies in the fact that a leaching is performed in two stages with acid returning from electrolysis.
When the operation (e) is excluded, the process of the invention provides for four different routes, which will be called "variants" below:
first variant:
performing the operation (c) in a single stage with only a portion of the ferrite residue produced in the operations (b) and (d)
second variant:
performing the operation (c) in a single stage with all of the ferrite residue produced in the operations (b) and (d)
third variant:
performing the operation (c) in two stages with only a portion of the ferrite
fourth variant:
performing the operation (c) in two stages with all of the ferrite.
When working in comparable conditions (the same concentrate and the same quantity of concentrate employed in (a), the same molar ratio of iron in the ferrite to the reactive sulphur in the concentrate employed in (c) and, when the first and the third variants are employed, the same fraction of ferrite used in (c)), the zinc output will be the lowest in the first variant and the highest in the fourth. In the first and third variants, the zinc output can be varied with the fraction of ferrite used in (c). In each of the four variants, the zinc output can also be varied by modifying the said molar ratio. As already mentioned above, the conventional process for the extraction of zinc, employed in the existing plants which make ferrite, already makes use of the reactions (I) and (II). The increase in output which is obtained by substituting the process of the invention for this conventional process in these plants will therefore be linked essentially with the quantity of zinc dissolved in (c) by the reactions (I) and (III). The first variant will therefore be employed when it is intended to produce a relatively small increase in capacity (for example from 5 to 10%) or when it is intended to produce a number of increases of small extent consecutively. The second variant will be employed to increase the plant capacity substantially, and the fourth when it is intended to increase the capacity further. The third variant will normally be employed only when it is intended, for any reason whatever, to continue to treat a portion of the ferrite by the conventional route and at the same time to draw maximum profit from the fraction of ferrite used in (c).
The molar ratio of the iron contained in the zinc ferrite to the reactive sulphur contained in the concentrate is at least approximately 0.2 and preferably at least 0.3 in order that the rate of leaching in (c) should not become too low. It is obvious that this ratio must be lower than 2 in order that it may still be possible to resort to the reaction (III). In the fourth variant, this ratio will be advantageously equal to or lower than 0.6, preferably equal to or lower than 0.4, in order that the zinc output should be at a maximum. This ratio of ≦0.6 is furthermore also suitable in the case of the other variants.
With regard to the conditions of the leaching in one stage (first and second variants):
the H 2 SO 4 content of the leachate which is rich in zinc and in iron is at least 45 g/l and preferably at least 55 g/l; otherwise, there is a risk of precipitating lead and silver jarosites which not only interfere with the leaching itself but can moreover subsequently be detrimental to the recovery of precious metals from the zinc residue; furthermore, an acid content which is too low also complicates the separation of the residue which is depleted in zinc from the leachate;
the H 2 SO 4 content of the leachate is not higher than 75 g/l and preferably not higher than 65 g/l; otherwise too much calcine must be employed in (d);
the Fe 3+ content of the leachate is 1-10 g/l, preferably 2-5 g/l, because in these conditions the leaching rate and yield are optimal.
It is particularly useful to take care that the trivalent iron concentration does not drop below approximately 0.1 g/l, preferably not below 0.2 g/l, during the initial phase of the leaching. If there is a drop below approximately 0.1 g/l of Fe 3+ , there is a risk not only of having corrosion problems, especially with the steels commonly employed for the construction of leaching equipment, but also of forming H 2 S and of seeing the copper disappear from the solution, copper which catalyses the reaction III. To avoid these problems, the potential of the pulp must be at least 530 mV (SHE) and preferably at least 560 mV. Furthermore, it is also advantageous to watch that the potential of the pulp does not rise above 640 mV in the said initial phase, because ferrite dissolves less quickly above 610 mV.
It is therefore important to check rigorously, especially using potential measurements, the trivalent iron concentration of the solution in the various phases of the leaching and to adjust this concentration as necessary by modifying the flow rate of oxygen and/or the temperature, a reduction in the temperature making the reactive sulphur less reducing and therefore less demanding for trivalent iron.
With regard to the conditions of leaching in two stages (third and fourth variants):
the H 2 SO 4 content of the leachate which is rich in zinc and in iron is at least 10 g/l; otherwise the leaching period is appreciably lengthened;
the H 2 SO 4 content of the said leachate is not higher than 35 g/l, preferably not higher than 25 g/l; otherwise too much calcine must be employed in (d);
the Fe 3+ content of the said leachate is 0.1-2 g/l, preferably 0.5-1 g/l; if there is a drop below 0.1 g/l of Fe 3+ , there is a risk of having the abovementioned problems; on the other hand, if there is a rise above 2 g/l of Fe 3+ , there is a risk of forming lead and silver jarosites, and this makes the separation of the leaching residue which is rich in zinc from the leachate which is rich in zinc and in iron much more difficult.
It is advantageous to oxidize at least 30%, preferably at least 40%, of the reactive sulphur in the second stage of leaching. If less than 30% of this sulphur is oxidized in the second stage, there is a risk of consuming too much acid in the first leaching stage and thus forming lead and silver jarosites, which not only interfere with the leaching itself but which can furthermore subsequently be detrimental to the recovery of the valuable metals from the leaching residue which is depleted in zinc.
It is particularly useful to perform the first stage of leaching so that the trivalent iron concentration of the solution, which will necessarily be low during the initial phase of this stage, reaches a value of 2-10 g/l, preferably of 3-7 g/l, in the final phase of this stage. It is, in fact, in these conditions that the leaching rate and yield become optimal.
It is furthermore important to take care that the trivalent iron concentration does not drop below 0.1 g/l, preferably not below 0.2 g/l, during the said initial phase, because otherwise there is a risk of having the abovementioned problems: corrosion, formation of H 2 S and disappearance of the copper from the solution. It is therefore important to watch that the potential is at least 530 mV and preferably at least 560 mV in the said initial phase and it is also important to control rigorously, especially by potential measurements, the trivalent iron concentration of the solution in the other phases of the first stage of leaching and to adjust this concentration as required, as mentioned above.
As already stated above, it is not advisable to consume too much acid in the first stage of leaching. In fact, it is appropriate to end this stage at an acid concentration of 40-70 g/l, preferably of 55-65 g/l. It is therefore important to watch that the quantities of acid, of ferrite and of sulphur (in the form of leaching residue which is rich in zinc) which are introduced in the first stage of leaching are such that the primary leachate has a sulphuric acid content of 55-65 g/l. The second stage of leaching is advantageously performed so as to maintain the trivalent iron concentration of the solution constantly at the above level of 0.1-2 g/l, preferably of 0.5-1 g/l, this being in order to avoid the abovementioned problems.
Other details and special features of the invention will emerge from the description of two embodiments of the process of the invention, which is given by way of nonlimiting example and with reference to the drawings enclosed herewith.
BRIEF DESCRIPTION OF THE DRAWINGS
In these drawings
FIG. 1 shows a diagram of an existing zinc plant employing the conventional process for zinc extraction;
FIG. 2 shows a diagram of an existing zinc plant which has been adapted for using an embodiment of the first variant of the process of the invention;
FIG. 3 shows a diagram of an existing zinc plant which has been adapted for using an embodiment of the fourth variant of the process of the invention;
FIG. 4 shows diagrammatically the plant used for performing the operations (c) and (d) in the embodiment of FIG. 3; and
FIG. 5 shows, on larger scale and in more detail, a tank of the plant of FIG. 4.
In these figures, the same reference numbers indicate identical components.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The plant shown in FIG. 1 receives a zinc sulphide concentrate 1 as feed. A portion 1a of this concentrate is roasted in 2 and a portion 3a of the calcine thus produced is subjected in 4 to a neutral leaching with sulphuric acid returning from electrolysis. The solution 5 leaving 4, which is rich in zinc and in iron-free substance, is purified in 6 and electrolysed in 7. The residue 8 from the neutral leaching, which is composed essentially of zinc ferrite and of gangue, is introduced into the first stage 9 of a hot acidic leaching in which stage the ferrite is leached with an acidic solution 12 produced in the second stage 10 of this hot acidic leaching. In the second stage 10, the residue 11 produced in 9 is leached in a very acidic medium with acid returning from electrolysis. The residue produced in 10 contains the gangue and insoluble compounds, especially lead sulphate. The solution 13 produced in 9 is a leachate which is rich in zinc and in iron: approximately 100 g/l Zn, 25-30 g/l Fe 3+ and 50-60 g/l H 2 SO 4 . This solution is treated in a reduction stage 14 with a second portion 1b of the concentrate to return its Fe 3+ content below 5 g/l. The residue 15 produced in 14 is recycled in 2 and the solution 16 of low Fe 3+ content, produced in 14, is treated in a neutralization stage 17 with a second portion 3b of the calcine produced in 2 to return its acid content below 10 g/l. The ferrite residue 18 produced in 17 is recycled at 9 and the conditioned solution 19 produced in 17 is treated in 20 in order to separate most of the iron from it, for example in the form of goethite 21. In this case, oxygen is injected in 20 into the solution while the latter is being neutralized, preferably with pure calcine 22 obtained by roasting pure ZnS concentrates, so as not to lose zinc in ferrite form. The solution 23 produced in 20, which is a solution rich in zinc and depleted in iron, is recycled at 4.
It has already been proposed in the literature to modify the conventional process described above in the sense that the reduction stage 14 is eliminated and that the second portion 2a of the concentrate is introduced into the first stage 9 of the hot acidic leaching, which then becomes a hot reducing acidic leaching.
FIG. 2 shows the plant of FIG. 1 after its adaptation for using the first variant of the process of the invention. An additional quantity 1c of the concentrate and a portion 8a of the ferrite are now leached in one stage with the acid returning from electrolysis in the presence of oxygen at 24 (operation (c)). The remainder 8b of the ferrite is treated in 9. The leaching residue which is depleted in zinc 25, produced in 24, is treated in 26 in order to extract from it the elemental sulphur S° and the valuable metals 27. When the solution which is rich in zinc and in iron 28, produced in 24, requires a reduction (solid line) it is added to the solution 13 (or to the hot reducing leaching, when the latter is present); otherwise it is added to the solution 16 (dotted line).
FIG. 3 shows the plant of FIG. 1 after its adaptation for using the fourth variant of the process of the invention. Since all of the ferrite 8 is now treated in the operation (c) and since in the embodiment which is to be described the operation (d) is incorporated in the operation (c), stages 9, 10, 14 and 17 are eliminated. The operation (c) is performed in two stages 29 and 30. In the first stage 29, the ferrite 8 and the leaching residue which is rich in zinc 31, produced in the second stage 30, are leached with returning acid in the presence of oxygen. The leaching residue which is depleted in zinc 25, produced in 29, is treated, as in the plant of FIG. 2, in 26 in order to extract the elemental sulphur S° and the valuable metals. In the second stage 30, an additional (substantial) quantity 1b of concentrate is leached in the presence of oxygen with the solution 32 produced in 29. At the end of the leaching in 30, a portion 3b of the calcine is added to the pulp so as to bring the acid content of the solution to below 10 g/l, after which the residue 31 is sent to the first stage 29 and the solution 19, which is already conditioned, to stage 20.
It is obvious that the equipment which is released by eliminating stages 9, 10, 14 and 17 can, for the most part, be reemployed for making use of stages 29 and 30.
The plant shown in FIG. 4 comprises a first series of four leaching tanks 33a, 33b, 33c and 33d which are placed in cascade and followed by a solid-liquid separator 34 and a second series of three leaching tanks 35a, 35b and 35c, also placed in cascade and followed by a neutralization tank 35d and a solidliquid separator 36. Each tank overflows into the following tank, except for the tanks 33d and 35d which overflow into the separators 34 and 36 respectively. The separator 34 comprises a thickener and a filtration apparatus, and the separator 36 a filtration apparatus.
The leaching tanks are closed and equipped, as shown in FIG. 5, with a feed inlet 37, an oxygen inlet 38, a spillway 39 and a self-sucking stirrer 40, for example a self-sucking stirrer with a hollow shaft or with a helical turbine with a suction sleeve. This stirrer has a threefold function: to keep the solids in suspension, to draw in and disperse the oxygen in the reaction mixture and to ensure, continuously, the recycling of the oxygen. The leaching tanks are also equipped with measuring and control devices which are not shown, for measuring the potential within and the pressure above the reaction mixture and for regulating the oxygen flow rate as a function of the pressure and the stirrer speed as a function of the potential, or vice versa. These tanks are furthermore provided with a device, not shown, for checking the temperature and with a safety valve.
Instead of being provided with a single multipurpose stirrer, the leaching tanks may be equipped with two stirrers: a constant-speed mixer-stirrer placed axially and used to keep the solids in suspension and to disperse the oxygen, and a variable-speed self-sucking stirrer placed eccentrically and used to recycle the unreacted oxygen. With this arrangement, it would be advisable to regulate the oxygen flow rate as a function of the potential and the speed of the self-sucking stirrer as a function of the pressure.
The neutralization tank 35d is provided with a feed inlet, a spillway, means for regulating the flow rate of calcine as a function of the acidity and a device for checking the temperature.
In the plant described above, the first stage of leaching 29 is performed in the first series of tanks and the second stage 30 in the second series of tanks.
The tank 33a is fed continuously with a stream of returning acid, with the bottom stream 8 of a thickener, not shown, which separates the products of the neutral leaching 4, and with the solid phase 31 leaving the filtration apparatus 36 which separates the products of the second stage of leaching 30; the stream 8 therefore contains zinc ferrite and the stream 32 the leaching residue which is rich in zinc, this residue also containing zinc ferrite, especially the ferrite originating from the calcine used in the neutralization tank 35d.
The products of the first stage of leaching, which leave the tank 33d, are separated in the separator 34 and the stream 32 of primary leachate which is thus obtained is introduced continuously together with the stream 1b of zinc sulphite concentrate into the tank 35a.
The flow rates of the returning acid stream and of the streams 1b, 3b and 8 are such that the molar ratio of the iron contained in the streams 8 and 32 to the reactive sulphur contained in the stream 1b is approximately 0.3 and that the sulphuric acid content of the stream leaving the tank 35c is approximately 20 g/l.
The pulp leaving the neutralization tank 35d has a sulphuric acid content of approximately 5 g/l.
The volumes of the tanks are such that the residence time of the reaction mixture is approximately 6 hours in the first series of tanks and approximately 5 hours in the second series of tanks.
In each leaching tank, the potential of the solution is maintained at an appropriate level, especially at 560-610 mV (SHE) in 33a, at 590-630 mV in 33b, at 610-650 mV in 33c, at 640-660 mV in 33d and at 560-620 mV in 35a, 35b and 35c. The checking of the potential and, hence, the trivalent iron content of the solution is performed by the abovementioned measuring and regulating devices.
The temperature in each leaching tank is kept at approximately 90° C. and the overpressure therein remains at a very low level, for example at 5-20 cm of water, or even less, by virtue of the action of the self-sucking stirrer.
The action of the abovementioned measuring and regulating devices will normally suffice to keep the potential at the intended level. However, if these devices were found for any reason whatsoever to be incapable by themselves of keeping the potential at the intended level, it would also be possible to intervene by varying the temperature.
When working as described above, approximately 45% of the reactive sulphur is oxidized in the second stage of leaching and a zinc leaching yield of approximately 98% is reached, this being therefore with a total leaching period of approximately 11 hours. The copper present in the concentrate 1b is found again almost entirely in the leachate 19, from which it will be subsequently separated, and the lead and the silver from the concentrate are found again in the leaching residue 25, from which they can be easily separated by flotation, because this residue is practically free from jarosites.
The streams 1a and 1b can obviously have the same composition or a different composition.
The number of tanks may vary. In fact, the leaching yield increases up to a certain point with the number of tanks, because with an increasing number of tanks it is possible to improve favourably the potential profile which it is desired to apply to the first stage of leaching and at the same time the probability that all the ore particles undergo leaching during the required period of time is increased. Needless to say, however, the cost of the plant also increases with the number of tanks. The choice of this number will therefore be determined by considerations of a technical and economic nature.
A major advantage of the process of the invention, namely the shortening of the duration of the operation (c), is illustrated by the examples given below.
EXAMPLE 1
This example describes a test of leaching in one stage (operation (c)) according to the process of the invention.
Starting materials employed
(α) 2 kg of a blende which has the following composition, in % by weight: 53.9 Zn, 5.6 Fe, 2.32 Pb, 30.5 S tot , 29.0 reactive S 2- (=S tot less pyrite S) and 0.02 Cu; this blende has a particle size of 90% smaller than 44 mm;
(β) 1215 g of a zinc ferrite which has the following composition, in % by weight: 20.9 Zn, 30.4 Fe and 5.78 Pb;
(γ) 22.5 l of a cell returning acid containing 189 g/l of H 2 SO 4 .
The molar ratio of the iron contained in (β) and the reactive sulphur contained in (α) is 0.36.
Apparatus employed
A closed tank of 30-l capacity, equipped with a feed inlet, an oxygen inlet, a stirrer, a potentiometer probe and means for controlling the temperature.
Leaching
(α) and (β) are added to (γ) over 60 minutes and at the same time the temperature is gradually increased from 75° to 90° C. At the end of this operation virtually all of the ferrite has dissolved. Oxygen injection is then commenced and leaching is continued. The reaction is stopped after 7.5 h.
Table 1 below gives the change in the main parameters during the leaching.
TABLE 1______________________________________Time mV T Fe.sup.2+ Fe.sup.3+ H.sub.2 SO.sub.4h (SHE) °C. g/l g/l g/l______________________________________1 590 90 10.6 0.2 1202 593 90 14.0 0.6 893 595 90 15.4 0.7 794 597 90 15.6 0.8 705 603 90 16.1 1.0 656 610 90 15.4 1.6 607 617 90 14.8 2.1 567.5 625 90 14.4 2.6 53______________________________________
The pulp is filtered and 26.5 l of leachate which is rich in zinc and in iron and 1095 g of residue which is depleted in zinc are obtained.
The leachate which is rich in zinc and in iron contains, in g/l: 14.4 Fe 2+ , 2.6 Fe 3+ and 53 H 2 SO 4 .
The residue which is depleted in zinc contains, in the dry state, in % by weight: 5.9 Zn, 1.3 Fe, 10.0 Pb, 57 S tot , 52 S° and 0.04 Cu.
The leaching yield of zinc is 95.2%.
EXAMPLE 2
This example describes a test of leaching in two stages (operation (c)) according to the process of the invention.
Starting materials employed
(α) as in Example 1;
(β') 937 g of a zinc ferrite which has the same composition as that of Example 1;
(γ') 14.8 l of a cell returning acid which has the same composition as that of Example 1;
(δ) 1429 g of a leaching residue which is rich in zinc, which has the following composition, in % by weight: 42.4 Zn, 4.5 Fe, 3.18 Pb, 42.9 S tot , 21.5 reactive S 2- , 18.8 S° and 0.05 Cu;
this residue was obtained during a previous operation which was substantially identical to the second stage of leaching which will be described below, which means that 47.0% of the reactive sulphur contained in (α) will be oxidized in this second stage of leaching.
The molar ratio of the iron contained in (β') to the reactive sulphur contained in (α) is therefore 0.28, whereas the molar ratio of the iron contained in (β') to the reactive sulphur contained in (δ) is 0.53.
Apparatus employed
As in Example 1, except that the closed tank has a capacity of 20 l.
First stage of leaching
First of all (δ) is added to (γ') over 30 minutes and then (β') over 60 minutes while the temperature is gradually raised from 75° to 90° C. during the first hour of this charging operation. Oxygen is injected during the charging only when the potential of the pulp falls below 560 mV. By first of all adding (δ') to (γ'), the potential of the solution is lowered to a level of 560-610 mV, at which--as the Applicant has ascertained--zinc ferrite dissolves most quickly. (The cell returning acid (γ') has a potential appreciably higher than 610 mV. In a batch leaching, it is therefore important to take measures in order that the potential of the acid should be rapidly returned to the level of 560-610 mV. Such measures are generally not required in a continuous leaching because the pulp to which the cell returning acid, the zinc ferrite and the leaching residue which is rich in zinc are added in this case will almost always have a potential lower then 610 mV.)
Once the charging is finished, the introduction of oxygen into the tank is commenced and the potential of the solution is gradually raised by increasing the flow rate of oxygen so as to obtain a value of 630-650 mv after 6 h of leaching.
Table 2 below gives the change in the main parameters during this first stage of leaching.
TABLE 2______________________________________Time mV T Fe.sup.2+ Fe.sup.3+ H.sub.2 SO.sub.4h (SHE) °C. g/l g/l g/l______________________________________1 571 90 5 0.15 1572 568 90 15.5 0.8 913 588 904 601 90 16.8 2.3 685 621 906 638 90 12.5 6.1 56______________________________________
The pulp is filtered and a primary leachate and 974 g of residue depleted in zinc are obtained.
The primary leachate (ε) contains, in g/l: 12.5 Fe 2+ , 6.1 Fe 3+ and 56 H 2 SO 4 .
The residue which is depleted in zinc contains, in the dry state, in % by weight: 3.2 Zn, 1.45 Fe, 9.2 Pb, 58 S tot , 55 S° and 0.03 Cu.
Second stage of leaching
The blende (α) is added continuously to the primary leachate (ε) over a period of time of 60 minutes while the temperature is raised at the same time from 65° C. to 85° C. The oxygen flow rate is adjusted so as to keep the potential of the solution between 560 and 590 mV. The leaching is stopped after 5 h.
Table 3 below gives the change in the main parameters during this second stage of leaching:
TABLE 3______________________________________Time mV T Fe.sup.2+ Fe.sup.3+ H.sub.2 SO.sub.4h (SHE) °C. g/l g/l g/l______________________________________0.5 751 561 85 16.5 0.6 522 570 85 16.8 1.1 403 578 85 16.9 0.9 304 580 85 17.1 1.1 225 574 85 17.2 1.0 17______________________________________
After filtration of the pulp, a leachate which is rich in zinc and the leaching residue which is rich in zinc (δ) are obtained.
The leachate which is rich in zinc contains, in g/l: 17.2 Fe 2+ , 1.0 Fe 3+ and 17 H 2 S0 4 .
The leaching yield of zinc is 98%, this being therefore after a leaching period of 11 hours.
EXAMPLE 3
This comparative example describes a test of leaching in two stages (operation (c)) according to the process of the prior art discussed above (EP-A-0451456).
Starting materials employed
(α) as in Example 1;
(β") 1215 g of a zinc ferrite which has the same composition as that of Example 1;
(γ") 16.6 l of a cell returning acid which has the same composition as that of Example 1;
(δ') 1008 g of a leaching residue which is rich in zinc, which has the following composition, in % by weight: 19.8 zn, 2.05 Fe, 4.5 Pb, 59 S tot , 10.3 reactive S 2- , 48 S° and 0.15 Cu; this residue was obtained during a previous operation which was appreciably identical to the second stage of leaching which will be described below, which means that this time 82.1% of the reactive sulphur contained in (α) will be oxidized in the second stage of leaching.
The molar ratio of the iron contained in (β") to the reactive sulphur contained in (α) is here 0.36, that is to say a little higher and therefore more favourable than in Example 2, whereas the molar ratio of the iron contained in (β") to the reactive sulphur contained in (δ') is now 2.03.
Apparatus employed
As in Example 2.
First stage of leaching
The charging is performed as in Example 2, that is to say that first of all (δ') is added to (γ") over 30 minutes and then (β") over 60 minutes while the temperature is gradually raised from 75° to 90° C. during the first hour. Leaching is then continued and is stopped after 4 h.
Attempts to lower the potential of the reaction mixture to the level of 560-610 mV, which favours the dissolution of the ferrite, were unsuccessful, probably because of the low content of reactive sulphur in (δ').
Table 4 below gives the change in the main parameters during this first stage of leaching.
TABLE 4______________________________________Time mV T Fe.sup.2+ Fe.sup.3+ H.sub.2 SO.sub.4h (SHE) °C. g/l g/l g/l______________________________________1 640 90 4.2 0.5 1662 679 90 10.8 4.2 1053 665 90 14.3 3.5 974 655 90 15.8 3.4 94______________________________________
The pulp is filtered and a primary leachate and 1079 g of residue which is depleted in zinc are obtained.
The primary leachate (ε') contains, in g/l: 15.8 Fe 2+ , 3.4 Fe 3+ and 94 H 2 SO 4 .
The residue which is depleted in zinc contains, in the dry state, in % by weight: 3 Zn, 1.7 Fe, 10.3 Pb, 56 S tot , 53 S° and 0.17 Cu.
Second stage of leaching
The blende (α) is added continuously to the primary leachate (ε') over a period of time of 60 minutes while at the same time the temperature is raised from 65° C. to 85° C. The oxygen flow rate is adjusted so as to keep the potential of the solution between 560 and 590 mV, as in Example 2. However, after approximately nine hours' leaching, it is no longer possible to keep the potential below 590 mV, which apparently means that the reactivity of the blende has become very low. Nevertheless, oxygen continues to be injected in order to make the blende react further, and the leaching is stopped after 16 h.
Table 5 below gives the change in the main parameters during this second stage of leaching.
TABLE 5______________________________________Time mV T Fe.sup.2+ Fe.sup.3+ H.sub.2 SO.sub.4h (SHE) °C. g/l g/l g/l______________________________________1 567 85 19.70 0.1 101.52 579 85 20.30 0.35 92.54 589 85 21.20 0.60 75.55 589 85 22.20 0.90 57.010 598 85 22.95 0.90 52.212 611 85 22.40 1.90 41.514 613 85 22.35 2.45 32.516 619 85 21.85 3.25 22.0______________________________________
After filtration of the pulp, a leachate which is rich in zinc and the leaching residue which is rich in zinc (δ") are obtained.
The leachate which is rich in zinc contains, in g/l: 20.2 Fe 2+ , 2.8 Fe 3+ and 22 H 2 SO 4 .
The leaching yield of zinc is 98%, this being therefore after a total leaching period of 20 hours.
When these examples are compared, it is seen that the time required to carry out the operation (c) in the process of the prior art exceeds by 114% that required to carry out this operation with practically the same yield in the first and second variants of the process of the invention, and by 82% that required to carry out this operation with the same yield in the third and fourth variants of the process of the invention. This is equivalent to saying that, with the process of the invention, as much is done in 0.47 reactor volume (1st and 2nd variants) or in 0.55 reactor volume (3rd and 4th variants) as with the process of the prior art in 1 reactor volume.
The industrial exploitation of the process of the invention will therefore entail investment costs which will be far lower than those of the process of the prior art.
It is obvious that some special features of the operation (c) which have just been described in connection with the process of the invention can be very useful in a context other than that of the process of the invention described above.
This is why the Applicant also requests protection for a process for leaching zinc ferrite together with a sulphide material containing zinc sulphide, according to which the leaching is performed with a solution of sulphuric acid at 60°-95° C. in atmospheric conditions so as to produce a leachate which is laden with zinc and with iron and a leaching residue which is depleted in zinc and in iron, this process being characterized in that
(1) the work is done with a sulphide material:ferrite ratio such that the quantity of reactive sulphur present in the sulphide material is appreciably higher than that which can be oxidized by the iron present in the ferrite, the reactive sulphur being the sulphur which is present in the form of sulphide and which can be converted into elemental sulphur by the ferric sulphate,
(2) a stream of sulphide material, a stream of ferrite and a stream of acid are introduced continuously into the first tank of a series of tanks, the pulp thus formed is passed successively through the other tanks of the series, a stream of oxygen is introduced into these other tanks and in each tank of the series conditions are maintained such that the pulp leaving the last tank consists of leachate laden with zinc and with iron and of leaching residue which is depleted in zinc and in iron, and
(3) care is taken that the potential of the pulp should not fall below 530 mV (SHE) and preferably not below 560 mV in the first tank.
The sulphide material may be a zinc sulphide concentrate or a partially leached zinc sulphide concentrate.
It is possible to refrain from introducing oxygen into the first tank and to keep the potential therein at at least 530 mv by working therein with a sulphide material:ferrite ratio which is sufficiently low and/or at a temperature which is sufficiently low.
It is also possible to keep the potential in the first tank at at least 530 mv by introducing an appropriate stream of oxygen into it.
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A portion of the concentrates is roasted and a portion of the resulting calcine is subjected to a neutral leaching step. Another portion of the concentrates is directly leached in an acidic medium in the presence of oxygen and under atmospheric conditions together with at least a portion of the neutral leaching residue. The zinc- and iron-rich solution resulting from acid leaching is neutralised with another portion of the calcine, the iron is removed and the solution is reused in the neutral leaching step. The method enables a gradual increase in the capacity of an existing zinc plant in accordance with demand, while capital costs may advantageously be spread out over time.
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FIELD OF THE INVENTION
The present invention relates to a novel class of polymeric compounds having specific quaternized amine based upon a dimer acid amido amine quaternary compound. Dimer acid is a C-36 diacid having a cyclic structure and two amine groups that allow for the synthesis of a high molecular weight cationic compound which is extremely substantitive to human skin and are well tolerated by human tissue making them suitable for use preparation of barrier products for personal care applications.
BACKGROUND OF THE INVENTION
It is very desirable to provide a material from aqueous solution that will condition the hair and still be compatible with anionic surfactants. This allows for the preparation of clear two in one shampoo systems, clear 2 in one shower gels, and clear two in one bath products. By two in one products in meant, a product that contains both anionic surfactant, most commonly sulfates and ether sulfates and a cationic conditioning agent. The anionic surfactant is the detergent, which cleans the hair or skin, and the cationic product is for conditioning providing softness, slip and feels to the skin. The problem with such product has always been the incompatibility of the anionic and cationic surfactants with each other. When many of these products are present in the same solution an insoluble salt forms making a cosmetically unacceptable white gunk that does not stay in solution.
As will become clear, by making a very large molecule the present invention results in a we call a soft quaternary compound. By soft quaternary compound is meant one that not withstanding its cationic charge is of a structure so that when placed in water along with the anionic surfactant, a clear stable solution is obtained. Surprisingly, because of the high molecular weight of the quaternary compound, the deposition on the hair and skin is increased. While not wanting to be held to only one mechanism, we believe there rather than a precipitate observed with so-called hard quats, compounds of the present invention form a self-assembling complex between the anionic and cationic surfactant. This complex, while water-soluble is large enough to disrupt hydrogen bonding between water molecules, and as such energetically, the complex will be deposited on the skin or hair leaving the remaining solution at the lowers free energy level.
The self-assembling aspect of the present invention, which we believe is the result of orientation of the salt of the cationic compounds of the present invention and the anionic surfactants present in solution, can be demonstrated by the fact that upon initial mixing of the components, a hazy or cloudy dispersion occurs. With suitable mixing, this hazy dispersion becomes a solution and the viscosity increases.
The compounds of the present invention can be formulated into body washes and other skin products and hair care products to provide a “delivery system” for conditioning the hair or skin. The high molecular weight of the quat and the fact that the point charges are far apart in the molecule results in through and efficient deposition on the hair or skin. This provides uniformity of conditioning agent over the entire hair of skin surface. This is particularly important for applications on hair for people with long hair. In general the long hair is more damaged, dry and in need of conditioning at the tip area, than near the root. The hair closest to the scalp is newer, less damaged, and less in need of conditioning. This dichotomy of hair condition is more effectively treated by the complexes formed by the current invention than by other quats. In addition, the di-nature of the compounds provides for outstanding substantivity of the molecule allow for very mild natural like materials that can be used in products where low irritation is important.
U.S. Pat. No. 6,331,293 issued Dec. 18, 2001 to Smith et al describes phosphobetaines that are derived from dimer acid. Unlike the compounds of the present invention, these materials are amphoteric surfactants and are barriers when applied to the skin. It is stated that the compounds are “extremely substantitive to human skin and are well tolerated by human tissue making them suitable for use preparation of barrier products for personal care applications”. Unlike these materials, the compounds of the present invention are not amphoterics, but are quats, are not barriers but are conditioning agents that do not build up on the hair or skin.
SUMMARY OF THE INVENTION
Objective of the Invention
It is the objective of the invention to provide a novel series of polymeric dimer amido quaternary compounds and a process of its use which comprises contacting the skin with an effective conditioning concentration of the novel quaternary compounds when applied in aqueous solution containing anionic surfactants. These anionic surfactants are preferably fatty sulfates and fatty ether sulfates having between 1 and 4 moles of ethylene oxide present. The polymeric nature of these materials makes them very substantive and minimally penetrating to the skin, making them both non-toxic and non-irritating.
In accordance with the present invention, we have now been discovered novel quaternary compound, which conforms to the following structure:
A—(B—C) x —A
wherein:
A is
wherein;
R is alkyl having between 7 and 27 carbon atoms, and includes linear, branched, saturated, unsaturated and polyunsaturated; B is —CH 2 CH(OH)CH 2 — C is selected from the group consisting of
and
wherein;
x is an integer ranging from 1 to 2000.
The difference between the two dimer species is that one of them has no double bond in the cyclic structure, while the first has a double bond. The double bond is removed by hydrogenation of the acid prior to making the quaternary compound. This variation has lighter color and better oxidative stability, making it prized for cosmetic applications where a water white product is desired. Consumers consider water white products as cleaner and more appealing over yellow products.
The present invention is also directed to a process for very efficiently conditioning the skin and hair from aqueous solution containing anionic surfactant. The complex that forms is very efficient in providing conditioning and can be used at concentrations as low as 0.5% by weight in a shampoo formulation. This is very important in products where low irritation is important like baby shampoo and bubble bath products.
The process for conditioning hair comprises contacting the hair with an effective conditioning concentration of a quaternary compound, which conforms to the following structure:
A—(B—C) x —A
wherein:
A is
wherein;
R is alkyl having between 7 and 27 carbon atoms, and includes linear, branched, saturated, unsaturated and polyunsaturated; B is —CH 2 CH(OH)CH 2 — C is selected from the group consisting of:
and
wherein;
x is an integer ranging from 1 to 2000.
The preferred effective conditioning concentration ranges from 0.5% to 25% by weight.
The polymers of the present invention are made in polar solvent, typically water, but can also be made in propylene glycol, polyoxyalkylene glycols and PEG/PPG dimethicone or combinations thereof. The selection of the proper solvent or combinations of solvents will determine the viscosity of the final polymer.
The use of PEG/PPG dimethicone as a solvent results not only in a relatively low viscosity product, but also results in a composition that has extremely efficient deposition on hair and skin, making the compositions highly desirable in personal care applications.
PREFERRED EMBODIMENTS
In a preferred embodiment R is —CH 3 (CH 2 ) 6 —.
In a preferred embodiment, R is —CH 3 (CH 2 ) 8 —.
In a preferred embodiment, R is —CH 3 (CH 2 ) 10 —.
In a preferred embodiment R is —CH 3 (CH 2 ) 12 —.
In a preferred embodiment, R is —CH 3 (CH 2 ) 14 —.
In a preferred embodiment, R is —CH 3 (CH 2 ) 16 —.
In a preferred embodiment R is —CH 3 (CH 2 ) 18 —.
In a preferred embodiment, R is —CH 3 (CH 2 ) 20 —.
In a preferred embodiment, R is —CH 3 (CH 2 ) 22 —.
In a preferred embodiment R is —CH 3 (CH 2 ) 24 —.
In a preferred embodiment, R is —CH 3 (CH 2 ) 26 —.
In a preferred embodiment x is 1.
DETAILED DESCRIPTION OF THE INVENTION
The present invention is directed to novel cationic compounds, which conform to one of the following structure:
A—(B—C) x —A
wherein:
A is
wherein;
R is alkyl having between 7 and 27 carbon atoms, and includes linear, branched, saturated, unsaturated and polyunsaturated; B is —CH 2 CH(OH)CH 2 — C is selected from the group consisting of
and
wherein;
x is an integer ranging from 1 to 2000.
The compounds of the present invention are made reaction of the 1,3 dichloro, 2 hydroxy propane with a mixture of mono tertiary amines and di-tertiary amines in a polar solvent.
Monofunctional Tertiary Amines
Monofunctional tertiary amines confirm to the following structure:
wherein;
R is alkyl having between 7 and 27 carbon atoms, and includes linear, branched, saturated, unsaturated and polyunsaturated, and
Di-functional Tertiary Amines
Di-functional tertiary amines are selected from the group consisting of compounds conforming to the following structures:
and
under aqueous conditions.
The polymerization process continues with the monofunctional tertiary amine being the chain terminator (A) unit, the hydroxy-propyl group being the (B) unit and the dysfunctional tertiary amine being the (c) unit. The product of the present invention is thereby attained as a polyquaternium. The higher the concentration of monofunctional tertiary amine, the lower the value of “x”. If no di-tertiary amine is added, x is 0, resulting in a bis-quat not a polymer. The polymer is not made with vinyl monomer, thereby making it vinyl monomer free and avoiding the toxicological problems inherent to levels of unreacted monomer left in vinyl polymers.
The compatibility of this novel quaternary compounds of the invention with human tissue, i.e., dermal and eye tissue has been tested. In these tests, 48-hour human patch dermal evaluations (5% in water), in vitro ocular evaluations (3% in water) and repeated insult patch tests (3% in water) determined that the compounds are substantially non-irritating to humans, they are safe and suitable for use in eye area products and are not a skin sensitizer to humans.
EXAMPLES
Dimer Acid and Hydrogenated Dimer Acid
Dimer acid and hydrogenated dimer acids are items of commerce commercially available from several suppliers, one of which is Cognis Corporation, formerly the Emery Division of Henkel.
Dimer acid conforms to the following structure;
Hydrogenated dimer acid conforms to the following structure;
DMAPA
Dimethylaminopropyl Amine is an item of commerce available from a variety of sources including Dow Chemical.
H 2 N—(CH 2 ) 3 —N—(CH 3 ) 2
1,3 di-chloro-2-hydroxy-propane
1,3 di-chloro-2-hydroxy-propane is a item of commerce available from a variety of sources including Dixie Chemical. It conforms to the following structure:
Cl—CH 2 —CH(OH)CH 2 —Cl
Mono-functional Tertiary Amines
Monofunctional Tertiary amines conform to the following structure:
wherein;
R is alkyl having between 7 and 27 carbon atoms, and includes linear, branched, saturated, unsaturated and polyunsaturated.
They are commercially available from a variety of manufacturers including Siltech LLC, Dacula, Ga.
Example
R
1
C 7 H 13
2
C 9 H 17
3
C 11 H 21
4
C 13 H 25
5
C 15 H 29
6
C 17 H 33
7
C 19 H 37
8
C 21 H 41
9
C 23 H 25
10
C 25 H 49
11
C 27 H 51
Di-functional Tertiary Amines
Example 12
Preparation of Dimer Amido Amine
To 561.0 grams if dimer acid is added 153.0 grams of dimethylaminopropyl amine. The mixture is heated to 180–200° C. and held for 3–8 hours. Once the temperature begins to reach 180° C., water begins to distill off. An excess of dimethylaminopropyl amine is added to speed up the reaction. When the acid value reaches 1.0 mg KOH/gram, the excess dimethylaminopropyl amine is stripped off by applying vacuum. The resulting product is the dimer amido amine useful as an intermediate in the preparation of the compounds of the present invention. The alkali value of the product so produced is 180.0 mg KOH/gm. The product is a yellow water insoluble liquid at ambient temperatures.
Example 13
Preparation of Dimer Amido Amine
To 563.0 grams if hydrogenated dimer acid is added 153.0 grams of dimethylaminopropyl amine. The mixture is heated to 180–200° C. and held for 3–8 hours. Once the temperature begins to reach 180° C., water begins to distill off. An excess of dimethylaminopropyl amine is added to speed up the reaction. When the acid value reaches 1.0 mg KOH/gram, the excess dimethylaminopropyl amine is stripped off by applying vacuum. The resulting product is the dimer amido amine useful as an intermediate in the preparation of the compounds of the present invention. The alkali value of the product so produced is 180.0 mg KOH/gm.
Example 14–24
Preparation of the Cationic of the Present Invention
Into a suitable reaction flask is charged the specified number of grams of the specified solvent. Next, add the specified number of grams of 1,3 dichloro 2 hydroxy propane. Heat is applied to 90° C. Next, the specified number of grams of the specified dimer amidoamine (either example 12 or 13), followed by the specified number of grams of the specified mono tertiary amine (examples 1–11) are charged into the reaction vessel under good agitation. The temperature is maintained at between 90° C. and 95° C., until the percentage of free tertiary amine is 0.5% maximum. During the reaction time, the pH is kept at between 7 and 8 with NaOH as required. The reaction mass will clear when the product is at 90 C for about 1 hour. The reaction time is approximately 6 to 9 hours. The % NaCl is monitored and the reaction is deemed complete when the % of theoretical NaCl reaches 98%.
The compound of the present invention is used without additional purification. It is a clear viscous liquid and is sold as an aqueous solution of between 30 and 40% solids by weight.
Example 14–24
Solvent
Mono Amine
Di Amine
1,3 dichloro-2 hydroxy
Example
Type
Grams
Example
Grams
Example
Grams
propane (grams)
14
Water
185.7
1
9.6
12
75.5
14.9
15
Water
150.0
2
5.6
13
78.8
15.5
16
DMC
50.0
3
2.6
12
81.4
16.1
Water
50.0
17
PG
300.0
4
1.4
13
82.3
16.2
18
Water
81.8
5
2.3
12
81.6
16.1
19
Water
100.0
6
25.5
12
62.3
12.3
20
PEG
185.7
7
6.8
13
77.8
15.3
21
Water
185.7
8
0.4
12
83.2
16.4
22
Water
150.0
9
17.3
12
69.0
13.6
23
Water
75.0
10
4.3
12
80.0
15.8
PG
75.0
24
Water
75.0
11
0.1
12
83.4
16.5
PG
75.0
DMC is PEG10 Dimethicone a commercial product marketed by Siltech LLC Dacula, Ga. as SILSURF Di1010.
PEG is polyoxyethylene glycol having a molecular weight of 400, marketed commercially by Phoenix Chemical Inc. Somerville, N.J.
PG is propylene glycol, marketed commercially by Phoenix Chemical Inc Somerville, N.J.
Additional Information
Example
x value
% Solids
14
10
35
15
20
40
16
50
50
17
10
25
18
1
55
19
67
50
20
5
35
21
600
35
22
10
40
23
50
40
24
2000
35
The products of the present invention range from low viscosity (300 cps for example 20) to a solid gel for example 24. The key to viscosity is the degree of polymerization (d.p.) which is reflected in the “x” value. As the “x” value increases the molecular weight of the resultant polymer increases and the % by weight of the mono tertiary amine decreases. Viscosity can also be lowered by using a non-aqueous polar solvent like propylene glycol or butylene glycol.
Applications Examples
The higher the molecular weight, the less likely the compound is to penetrate the skin. Since contact with skin is expected in washing the hair, even for hair use the higher molecular weight components are desired. The polymers of the present invention are not made by free radical polymerization. Consequently, they have no residual monomer content. This has become a major issue in selecting polymers for personal care.
The compounds of the present invention provide outstanding wet comb and conditioning properties to hair. They reduce static build up and provide gloss. The polymers of the present invention provide an outstanding smooth dry feel on the skin. The polymers of the present invention are non-toxic, and non-irritating.
While the illustrative embodiments of the invention have been described with particularity, it will be understood that various other modifications will be apparent to and can be readily made by those skilled in the art without departing from the spirit and scope of the invention. Accordingly, it is not intended that the scope of the claims appended hereto be limited to the examples and descriptions set forth hereinabove but rather that the claims be construed as encompassing all the features of patentable novelty which reside in the present invention, including all features which would be treated as equivalents thereof by those skilled in the art to which the invention pertains.
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The present invention relates to a novel class of polymeric compounds having specific quaternized amine based upon a dimer acid amido amine quaternary compound. Dimer acid is a C-36 diacid having a cyclic structure and two amine groups that allow for the synthesis of a high molecular weight cationic compound which is extremely substantitive to human skin and are well tolerated by human tissue making them suitable for use preparation of barrier products for personal care applications.
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[0001] This application is a Divisional application of U.S. application Ser. No. 13/505,148 filed 30 Apr. 2012, which is a National Stage Application of PCT/IN2010/000714, filed 1 Nov. 2010, which claims benefit of Serial No. 1000/KOL/2010, filed 9 Sep. 2010 in India, and which also claims benefit of Serial No. 1303/KOL/2009, filed 30 Oct. 2009 in India and which applications are incorporated herein by reference. To the extent appropriate, a claim of priority is made to each of the above disclosed applications.
TECHNICAL FIELD OF THE INVENTION
[0002] The present invention provides a novel process for preparation of darunavir that involves reduction of [(1S,2R)-3-[[(4-nitrophenyl)sulfonyl](2-methylpropyl)amino]-2-hydroxy-1-(phenylmethyl)propyl]carbamic acid (3R,3aS,6aR)-hexahydrofuro[2,3-b]furan-3-yl ester, of formula (5).The present invention is also related to darunavir ethanolate of fine particle size and process for its preparation.
BACKGROUND OF THE INVENTION
[0003] Darunavir is a potent HIV protease inhibitor belonging to the class of hydroxyethyl amino sulfonamides. Darunavir is known by chemical name [(1S,2R)-3-[[(4-aminophenyl)sulfonyl](2-methylpropyl)amino]-2-hydroxy-1-(phenylmethyl)propyl]carbamic acid (3R,3aS,6aR)-hexahydrofuro[2,3-b]furan-3-yl ester. Darunavir is generically disclosed in U.S. Pat. No. 5,843,946 and specifically disclosed in U.S. Pat. No. 6,248,775.
[0004] The ethanol solvate of darunavir, referred as Darunavir ethanolate is represented by following structure:
[0000]
[0005] Darunavir ethanolate is marketed in USA by Tibotec Pharmaceuticals under the trade name Prezista® and is specifically covered by U.S. Pat. No. 7,700,645.
[0006] We observed that very few references are directed towards synthesis of darunavir. The product patent U.S. Pat. No. 6,248,775 B2 does not provide any enabling disclosure for preparation of darunavir (1).
[0007] The process described in the publication Dominique et. al; Journal of Medicinal Chemistry, 2005, 48(6), 1813-1822 and the patent application US 2007/060642 A1 which involves condensation of diamino compound (2) with furanyl derivative (3) is most relevant to the present invention and is depicted in scheme 1 below.
[0000]
[0008] The synthesis of darunavir (1) by coupling of diamino compound (2) with furanyl derivative (3) very likely leads to formation of impurities, viz., impurity A and impurity B. However, the formation of these impurities A and B is not mentioned in any of the prior art references. The structural formulae of impurity A and impurity B are as represented below:
[0000]
[0009] These impurities can form due to presence of 4-amino group in the 4-aminophenylsulfonyl group on the tertiary nitrogen of diamino compound (2), since it can react with furanyl derivative (3). Due to prevalence of these impurities the process of above mentioned prior art is less desired and there is a need to develop an improved process.
[0010] The publication Dominique et. al; Journal of Medicinal Chemistry, 2005, 48(6), 1813-1822 further discloses preparation of nitro compound (5) by reaction of amino compound (4) with furanyl derivative (3) (where R=succinimidyl group) in presence of triethylamine in tetrahydrofuran to obtain nitro compound (5). Surprisingly, this publication does not provide any suggestions for reduction of nitro compound (5) to obtain darunavir (1). The process disclosed in this publication is depicted in the synthetic scheme 2.
[0000]
[0011] The inventors of the present invention have developed a novel process, which not only avoids formation of impurities A and B but also performs reduction of nitro compound (5) under selective condition in such a way that decomposition of carbamate linkage occurs to a lesser extent.
[0012] It is well known that particle size can affect the solubility properties of a pharmaceutical compound. Particle size reduction can increase a compound's dissolution rate and consequently its bioavailability. Particle size can affect how freely the crystals or powdered form of the drug will flow past each other, which has consequence in production process of pharmaceutical products containing the drug. The inventors of the present invention have developed darunavir ethanolate of fine particle size, which has good solubility and is well suited for preparing pharmaceutical products.
SUMMARY OF THE INVENTION
[0013] The present invention provides a novel process for preparation of darunavir of formula (1), comprising the steps of:
(i) condensation of the amino compound of formula (4) with furanyl derivative (3) to obtain nitro compound of formula (5); (ii) reduction of nitro compound of formula (5) to obtain darunavir; and (iii) optionally converting darunavir to darunavir ethanolate.
[0017] The present invention also provides darunavir ethanolate of particle size wherein d 0.9 is less than 130 μm, d 0.5 is less than 30 μm and d 0.1 is less than 10 μm. The present invention further provides a process for preparation of darunavir ethanolate of fine particle size comprising the steps of:
(i) feeding darunavir ethanolate to milling chamber under nitrogen pressure; (ii) rotating the milling chamber; and (iii) collecting the smaller size particles.
DESCRIPTION OF THE INVENTION
[0021] The present invention provides a novel process for preparation of darunavir of formula (1)
[0000]
[0000] comprising the steps of:
(i) condensation of the amino compound of formula (4)
[0000]
[0000] with furanyl derivative of formula (3)
[0000]
[0000] where R=succinimidyl, p-nitrophenyl, imidazolyl, phenyl, chloro or the like, to obtain nitro compound of formula (5);
[0000]
(ii) reduction of nitro compound of formula (5) to obtain darunavir (1); and
(iii) optionally converting darunavir (1) to darunavir ethanolate.
[0025] The process of present invention is depicted in scheme 3 given below
[0000]
[0026] The starting compound (4) can be obtained by the methods known in U.S. Pat. No. 6,248,775 B2 and US 2007/060642 A1. The furanyl derivative (3) is obtained by reaction of (3R,3aS,6aR) hexahydrofuro[2,3-b]furan-3-ol of formula (6)
[0000]
[0000] with succinimidyl carbonate, bis (4-nitrophenyl) carbonate, diimidazole carbonate, ter-butyloxycarbonyl anhydride, phenyl chloroformate, p-nitrophenyl chloroformate, phosgene etc.
[0027] The compound (3R,3aS,6aR) hexahydrofuro[2,3-b]furan-3-ol (6) employed for preparation of furanyl derivative (3) can be obtained by methods described in literature such as U.S. Pat. No. 6,919,465; WO 2008/055970 A2; WO 2005/095410 A1; WO 03/022853 A1; Dominique et. al, Journal of Medicinal Chemistry, (2005), 48(6), 1813-1822; Ghosh et. al, Journal of Organic Chemistry, (2004), 69(23), 7822-7829; Ghosh et. al, Journal of Medicinal Chemistry, (1996), 39, 3278-3290; Ghosh et. al; Tetrahedron Letters, (1995), 36(4), 505-508.
[0028] In one embodiment, the present invention provides a process for preparation of darunavir by carrying out coupling of the amino compound (4) with furanyl derivative (3) in a solvent or mixture of solvents in presence of a base to obtain the nitro compound (5).
[0029] The molar equivalent of furanyl derivative (3) with respect to amino compound (4) is in the range of 0.8 to 3, preferably 1.0 to 1.2.
[0030] The coupling is carried out in a solvent selected from lower alcohols such as methanol, ethanol, n-propanol, isopropanol; ketones such as acetone, ethylmethyl ketone, diethyl ketone, methylisobutyl ketone; lower aliphatic esters such as ethyl acetate, methyl acetate; halogenated hydrocarbons such as dichloromethane, chloroform dichloroethane; dimethylformamide, dimethyl sulfoxide, acetonitrile, water or mixtures thereof. Most preferably dichloromethane is used as a solvent for coupling reaction.
[0031] The coupling reaction is carried out in presence of an organic or inorganic base. The organic base is selected from triethylamine, diisopropylethyl amine, pyridine and the like while inorganic base is selected from hydroxides of alkali metals or alkaline earth metals such as sodium hydroxide, potassium hydroxide, lithium hydroxide; bicarbonates of alkali metals or alkaline earth metals such as sodium bicarbonate, potassium bicarbonate and the like; carbonates of alkali metals or alkaline earth metals such as sodium carbonate, potassium carbonate; ammonia or the like. Most preferably triethylamine is used as a base.
[0032] The molar ratio of base with respect to amino compound (4) is in the range of 0.5 to 6 molar equivalents, more preferably 1 to 3 molar equivalents, most preferably 2 molar equivalents.
[0033] The coupling reaction is carried out at a temperature ranging from −20° C. to 100° C., more preferably in range of 0° C. to 50° C., most preferably at 20-30° C.
[0034] In another preferred embodiment, the present invention provides a novel process for reduction of the nitro compound (5) in an organic solvent or mixture of solvents in presence of a transition metal catalyst to obtain darunavir.
[0035] Solvent suitable for reduction of the nitro compound (5) may be selected from lower alcohols such as methanol, ethanol, isopropyl alcohol, ter-butyl alcohol; aliphatic esters such as ethyl acetate, methyl acetate, isopropyl acetate; amides such as dimethyl formamide; aliphatic halogenated hydrocarbons such as dichloromethane, chloroform; aromatic hydrocarbons such as benzene, xylene, toluene; ethers such as diethyl ether, diisopropyl ether, tetrahydrofuran, 1,4-dioxane; dimethylsulfoxide, water or any mixtures thereof. More preferably esters such as ethyl acetate, methyl acetate, isopropyl acetate are used, most preferably ethyl acetate is employed.
[0036] The catalyst employed for reduction is selected from transition metal catalyst such as palladium on carbon, PtO 2 , Raney Nickel, ruthenium, rhodium; iron in acidic medium; borane complexes, diborane; borohydrides such as sodium borohydride, lithium aluminium hydride and the like.
[0037] The reduction of the nitro compound (5) is more preferably carried out by catalytic hydrogenation in presence of transition metal catalyst selected from palladium on carbon, PtO 2 and Raney nickel. Palladium on carbon is most preferred amongst these.
[0038] The hydrogenation is carried out at a temperature ranging from −20° C. to 100° C., more preferably in range of 0° C. to 50° C., most preferably at 20-30° C.
[0039] The reduction of nitro moiety is optionally carried out in presence of an organic or inorganic base. The organic base is selected from triethylamine, diisopropylethyl amine, pyridine and the like while inorganic base is selected from hydroxides of alkali metals or alkaline earth metals such as sodium hydroxide, potassium hydroxide, lithium hydroxide; bicarbonates of alkali metals or alkaline earth metals such as sodium bicarbonate, potassium bicarbonate and the like; carbonates of alkali metals or alkaline earth metals such as sodium carbonate, potassium carbonate; ammonia or mixtures thereof. Most preferably triethylamine is used as a base.
[0040] The molar ratio of base with respect to nitro compound (5) is in the range of 0.5 to 5 molar equivalents, more preferably 1 to 3 molar equivalents, most preferably 1.5 molar equivalents.
[0041] The process of present invention has following advantages over the prior art method:
1. It employs condensation of amino compound (4) with the furanyl derivative (3), which avoids formation of impurity A and impurity B. 2. The reduction of nitro compound (5) by catalytic hydrogenation is preferably carried out in basic condition, which prevents cleavage of the carbamate linkage. 3. Better yield of darunavir. 4. Enhanced purity of darunavir.
[0046] In another aspect the invention provides darunavir ethanolate having particle size wherein d 0.5 is less than 30 μm.
[0047] In yet another aspect the invention provides darunavir ethanolate having particle size wherein d 0.9 is less than 130 μm and d 0.5 is less than 30 μm.
[0048] In yet another aspect the invention provides darunavir ethanolate having particle size wherein d 0.9 is less than 130 82 m, d 0.5 is less than 30 μm and d 0.1 is less than 10 μm.
[0049] Comminution of darunavir ethanolate may be performed by any of the known methods of particle size reduction. The principal operations of conventional size reduction are milling of a feedstock material and sorting of the milled material by size.
[0050] Micronization is carried out by known methods such as jet milling, media milling, pulverization and the like. Preferably micronization is carried out in a jet mill type micronizer.
[0051] In another embodiment, the present invention provides a process for preparation of darunavir ethanolate having fine particle size comprising the steps of:
(i) feeding darunavir ethanolate to milling chamber under nitrogen pressure; (ii) rotating the milling chamber; and (iii) collecting the smaller particles.
[0055] Darunavir ethanolate employed could be in the form of crystals, powdered aggregates and coarse powder of either crystalline or amorphous form.
[0056] All the steps of above mentioned micronization process are performed at ambient temperature. The feedstock of solid particles of darunavir ethanolate is tangentially fed in to the circular milling chamber. Milling chamber is rotated at a speed of 10-50 rpm, more preferably at 20-30 rpm for a time period of 1-10 hours, preferably for 3-7 hours. Milling chamber is supplied with nitrogen under pressure of approximately 1-5 Kg/cm 2 , more preferably 2-3 Kg/cm 2 . The particles are accelerated in a spiral movement in the milling chamber by number of angular holes in the ring and deposited on the periphery of the chamber. The milling action takes place due to high velocity of nitrogen. Larger particles get retained at the periphery due to centrifugal force and smaller particles travel along with the exhaust nitrogen through central port and get collected in the collection chamber.
[0057] The particle size of the darunavir ethanolate obtained by the process of present invention can be determined by any method known in the art such as laser diffraction, sieve analysis, microscope observation, sedimentation etc. Malvern mastersizer is an instrument employed for particle size determination in the present invention.
[0058] The invention is further defined by reference to the following examples. It is apparent to those skilled in the art that many modifications, both to materials and methods, may be practiced without departing from scope of the invention.
Example 1
Preparation of Nitro Compound (5)
[0059] The solution of 3.5 g (0.013 mol) of furanyl derivative (3) in a mixture of 50 ml of dichloromethane and 50 ml of acetonitrile was cooled to 0-5° C. and 1.98 ml (0.014 mol) of triethylamine was added. To the mixture 5 g (0.011 mol) of amino compound (4) was added and stirred for 1 hour. The reaction mixture was warmed to room temperature. To the reaction mixture 0.2 g of 40% aqueous solution of methyl amine was added and was heated till completion of the reaction. The reaction mixture was washed twice with 10% sodium carbonate solution (25 ml×2) and layers were separated. The organic layer was washed with water, dried over sodium sulfate and evaporated to dryness under vacuum. The residue was recrystallized from 50 ml ethanol and dried under vacuum at 40-45° C.
[0060] Yield=5.8 g
Example 2
Preparation of Darunavir
[0061] The solution of 5 g (0.009 mol) of nitro compound (5) in 100 ml of ethyl acetate was prepared by warming and cooled to room temperature. To the solution 2.5 ml (0.018 mol) of triethylamine and 0.5 g of 10% Pd/C (50% wet) were added. Hydrogenation was carried out at 3 Kg pressure for 1-2 hours at room temperature. Catalyst was filtered off and washed with 10 ml ethyl acetate. Solvent was evaporated under reduced pressure to obtain residue. To the residue 110 ml isopropyl alcohol was added and heated to 70-75° C. to obtain clear solution. It was cooled to room temperature and stirred for 1 hour. The crystals obtained were filtered, washed with isopropyl alcohol and dried under vacuum.
[0062] Yield=4.7 g
Example 3
Preparation of Darunavir Ethanolate
[0063] 100 gm of darunavir was dissolved in 1000 ml of denatured ethanol (mixture of 97% ethanol and 3% toluene) at 70-75° C. to obtain clear solution. 5 gm of activated charcoal was added and stirred for 120-150 minutes. The hot solution was filtered through hyflow bed and the bed was washed with 100 ml ethanol. The solution was filtered again through 0.2μ filter maintaining temperature at 70-75° C. The reaction mass was cooled to 15-20° C., stirred for an hour and filtered. The wet cake was washed with 100 ml of chilled ethanol and dried under vacuum at 40-45° C. to afford 89.5 gm of off white colored crystalline solid.
Example 4
Preparation of Darunavir Ethanolate of Fine Particle Size
[0064] 37.3 Kg of darunavir ethanolate obtained as per process described in example 1 was tangentially fed in to the circular milling chamber of the jet mill micronizer through a venturi under nitrogen at a pressure of about 2 Kg/cm 2 . The milling chamber was rotated at a speed of 28 rpm at ambient temperature for 3-7 hours. The smaller particles were collected in the collection chamber.
[0065] Yield=0.99 Kg (w/w)
[0066] Particle size distribution: d 0.9 =97 μm; d 0.5 =18 μm; d 0.1 =2 μm
[0067] Purity (by HPLC assay)=99.7%
[0068] Bulk density=0.42 g/ml
[0069] Tapped density=0.72 g/ml
[0070] Any other individual impurity was below detection limit (by HPLC).
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The present invention provides a novel process for preparation of darunavir that involves reduction of [(1S,2R)-3-[[(4-nitrophenyl)sulfonyl](2-methylpropyl)amino]-2-hydroxy-1-(phenylmethyl)propyl]carbamic acid (3R,3aS,6aR)-hexahydrofuro[2,3-b]furan-3-yl ester, of formula (5). The present invention also provides darunavir ethanolate of particle size wherein d 0.9 is less than 130 μm, d 0.5 is less than 30 μm, d 0.1 is less than 10 μm and process for its preparation.
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CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims priority to U.S. Provisional Application No. 61/615,970, filed Mar. 27, 2012, which is hereby fully incorporated by reference.
TECHNICAL FIELD
[0002] The disclosed embodiments relate to a conductor interface used with photovoltaic modules and methods for manufacturing photovoltaic modules having a conductor interface.
BACKGROUND OF THE INVENTION
[0003] Photovoltaic (PV) modules are becoming increasingly popular for providing renewable energy. In order to provide internally generated electricity to outside the module, a conductor interface (also referred to as a cord plate) is typically provided. The conductor interface is attached to the module over an opening in the module and provides an area for external conductors to be electrically connected to internal conductors of the module.
[0004] FIG. 1 shows a back perspective view of a conventional photovoltaic module 10 . Module 10 is oriented to receive sunlight through a front surface 110 and converts photons in the received sunlight to electricity using internal semiconductors arranged into a plurality of PV cells. The PV cells can be connected in series, parallel, or a combination thereof depending on the desired electrical output from module 10 . Brackets 115 connected to module 10 (for example, to peripheral edges of front surface 110 and back surface 140 ) may be used to fix module 10 to a support structure.
[0005] As shown in FIG. 1 , external conductors 120 , 125 extend from a conductor interface 150 that is affixed to the back surface 140 of module 10 .
[0006] External conductors 120 , 125 provide the electrical current generated by module 10 to external electrical devices or loads. External conductors 120 , 125 may be any appropriate wires or cables known in the art, and may include insulating jacket(s) surrounding their conductive core. External conductors 120 , 125 may include industry-compliant connectors 130 , 135 for ease of installation and interconnection with other elements in a photovoltaic system.
[0007] FIG. 2 shows an exploded view of the conductor interface 150 , which is affixed over an opening 405 in back surface 140 . Conductor interface 150 houses the interconnections of internal conductors 410 , 415 that are connected to an internal bussing system of module 10 with external conductors 120 , 125 . Conductor interface 150 includes a base portion 152 and a cover portion 154 . Base portion 152 affixes to back surface 140 , and cover portion 154 attaches to base portion 152 after external conductors 120 , 125 ( FIG. 1 ) are electrically connected to internal conductors 410 , 415 .
[0008] The internal conductors 410 , 415 extend through an opening 405 in back surface 140 of module 10 . Internal conductors 410 , 415 may be, for example, foil tabs that are connected to an internal bussing system of module 10 , such as a positive and a negative bus terminal within module 10 . Internal conductors 410 , 415 are folded back against back surface 140 , such that conductor interface 150 can be placed over the opening 405 and internal conductors 410 , 415 . An adhesive sealant 420 , for example, a dual-sided adhesive foam tape or other adhesive sealant that surrounds the internal conductors 410 , 415 and opening 405 , is typically used to affix conductor interface 150 to back surface 140 .
[0009] FIG. 3 shows a bottom surface of a conductor interface 150 , which is flat to accommodate adhesive sealant 420 ( FIG. 2 ) and forms a cavity 170 . External conductors 120 , 125 ( FIG. 1 ) can be inserted into respective wire holes 160 , 165 of conductor interface 150 , and terminal portions of external conductors 120 , 125 are welded, soldered, or otherwise electrically connected to a respective one of internal conductors 410 , 415 within cavity 170 after conductor interface 150 is affixed to back surface 140 . A potting material or other sealant can then be used to fill cavity 170 within conductor interface 150 , in order to prevent moisture and other elements from entering into cavity 170 of conductor interface 150 . Cover portion 154 is then attached to base portion 152 after the potting material fills cavity 170 .
[0010] During the electrical connection of the terminal portions of external conductors 120 , 125 to internal conductors 410 , 415 , wire portions of external conductors 120 , 125 are pressed down within cavity 170 and against adhesive sealant 420 . For example, wire portions of the external conductors 120 , 125 within cavity 170 can be pressed down on adhesive sealant 420 from approximately half the distance between the wire holes 160 , 165 and the respective electrical connection points. This can prevent potting material from fully encircling external conductors 120 , 125 along this distance, which can result in an imperfect seal or a seal that can weaken over time between the potting material and the remaining portions of the external conductors 120 , 125 . If the seal between the potting material and these remaining portions is not completely formed or breaks, moisture or other elements may enter conductor interface 150 and affect the electrical connections or enter the opening 405 of module 10 .
[0011] Accordingly, it is desirable to manufacture a photovoltaic module having a conductor interface that is more thoroughly sealed against moisture ingress.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a bottom perspective view of a photovoltaic module.
[0013] FIG. 2 is an exploded view of a bottom surface of a photovoltaic module.
[0014] FIG. 3 is a bottom perspective view of a conventional conductor interface.
[0015] FIG. 4 is a top perspective view of a conductor interface, in accordance with embodiments described herein.
[0016] FIG. 5 is a bottom perspective view of a conductor interface, in accordance with embodiments described herein.
[0017] FIG. 6 is a bottom perspective view of a conductor interface, in accordance with embodiments described herein.
[0018] FIG. 7 is a bottom perspective view of a conductor interface, in accordance with embodiments described herein.
[0019] FIG. 8 is a bottom perspective view of a conductor interface, in accordance with embodiments described herein.
[0020] FIG. 9 shows a conductor interface mounted on a surface, in accordance with embodiments described herein.
[0021] FIG. 10 is a bottom perspective view of a conductor interface, in accordance with embodiments described herein.
[0022] FIG. 11 is a bottom perspective view of a conductor interface, in accordance with embodiments described herein.
[0023] FIG. 12 is a bottom perspective view of a conductor interface, in accordance with embodiments described herein.
[0024] FIG. 13 is a bottom perspective view of a conductor interface, in accordance with embodiments described herein.
DETAILED DESCRIPTION
[0025] In the following detailed description, reference is made to the accompanying drawings which form a part hereof, and which illustrate specific embodiments of the invention. These embodiments are described in sufficient detail to enable those of ordinary skill in the art to make and use them. It is also understood that structural, logical, or procedural changes may be made to the specific embodiments disclosed herein.
[0026] FIGS. 4 and 5 respectively show a top and bottom perspective of an embodiment of a conductor interface 250 , which may be used to house interconnections of electrical conductors for a photovoltaic module. Conductor interface 250 includes a base portion 205 and a top portion 210 . Base portion 205 can be mounted adjacent to a mounting surface, such as a back surface 140 of a photovoltaic module 10 . Top portion 210 connects with base portion 205 and defines a pair of cavities 270 , 275 ( FIG. 5 ) within conductor interface 250 for respectively housing electrical interconnections between module internal and external conductors. Top portion 210 may include openings 272 , 274 exposing the cavities 270 , 275 within conductor interface 250 . Cavities 270 , 275 , respectively, provide areas that allow electrical connection of terminal portions 122 , 127 of external conductors 120 , 125 with internal module conductors 410 , 415 .
[0027] Base portion 205 and top portion 210 may be a single piece, or may be two separate connectable pieces capable of being connected using interlocking connectors (e.g., a snap connector), an adhesive, or other techniques known in the art. Top portion 210 includes downwardly extending sidewalls that meet and interconnect with upwardly extending sidewalls of base portion 205 . In other embodiments, top portion 210 may be a flat plate configured to interconnect with the upwardly extending sidewalls of base portion 205 .
[0028] Conductor interface 250 may be formed from plastic, metal, or other appropriate materials. For example, conductor interface 250 may be formed from a plastic or polycarbonate material shaped through an injection molding process.
[0029] Conductor interface 250 includes wire holes 260 , 265 , through which external conductors 120 , 125 ( FIG. 6 ) can respectively be inserted. A silhouette of wire hole 265 is shown because it is on the backside of conductor interface 250 in the perspective shown in FIG. 4 . Although two wire holes 260 , 265 are shown in FIG. 4 , it should be understood that a conductor interface 250 may have fewer or more wire holes to accommodate the number of electrical connections that need to be made to internal conductors of a module 10 .
[0030] FIG. 6 shows a bottom perspective of base portion 205 with external conductors 120 , 125 inserted into wire holes 260 , 265 , respectively. As noted above with respect to FIG. 5 , base portion 205 can be connected to top portion 210 , or base portion 205 and top portion 210 can be formed as a single piece.
[0031] The bottom surface 290 of base portion 205 includes respective connection cavities 270 , 275 and wire cavities 280 , 285 . As shown in FIG. 6 , an external conductor 120 traversing wire hole 260 extends through wire cavity 280 into connection cavity 270 . An external conductor 125 traversing wire hole 265 extends through wire cavity 285 into connection cavity 275 . External conductors 120 , 125 include respective terminal portions 122 , 127 , which can be electrically connected to respective internal conductors 410 , 415 of photovoltaic module 10 ( FIG. 2 ) within the respective connection cavities 270 , 275 .
[0032] Wire cavities 280 , 285 surround wire portions of the external conductors 120 , 125 inserted into respective wire holes 260 , 265 . Wire cavities 280 , 285 are enclosed above and open below the respective locations for the wire portions of external conductors 120 , 125 . Connection cavities 270 , 275 house the terminal portions 122 , 127 of external conductors 120 , 125 , which include the exposed electrically conductive material used to form electrical connections, such as when soldered to internal conductors 410 , 415 of a photovoltaic module 10 ( FIG. 2 ). Connection cavities 270 , 275 may be enclosed above the locations for the terminal portions 122 , 127 by a separate top portion 210 that is attached after electrical connections within connection cavities 270 , 275 are completed. In other embodiments, connection cavities 270 , 275 may be exposed through openings 272 , 274 of top portion 210 ( FIG. 4 ) to permit electrical connection of terminal portions 122 , 127 to internal conductors 410 , 415 ( FIG. 2 ) after top portion 210 is attached or if top portion 210 and base portion 205 are formed as a single piece.
[0033] The bottom surface 290 of base portion 205 includes a raised feature 230 partially surrounding connection cavity 270 and wire cavity 280 , and a raised feature 235 partially surrounding connection cavity 275 and wire cavity 285 . These raised features 230 , 235 act as standoffs and enable the use of a fluid adhesive, such as a glue or paste, to be applied between base portion 205 and a module 10 for bonding conductor interface 250 to the module 10 .
[0034] The fluid adhesive may be, for example, a water, silicone, urethane, or epoxy-based adhesive. The fluid adhesive may be, for example, a one-part adhesive that cures through exposure to air, or may be a two-part adhesive including a resin and a catalyst for stimulating curing of the resin. The fluid adhesive may be selected to have a high adhesive strength to glass and polycarbonate and a high intrinsic tensile strength. For example, the fluid adhesive may have a tensile strength rating (ASTM D412) that is greater than approximately 1.5 MPa, and an adhesive strength to bottom surface 290 of conductor interface 250 and to module 10 that is greater than the tensile strength. The fluid adhesive may be an adhesive capable of withstanding damp heat conditions and having a high flammability rating. For example, the fluid adhesive may be a one or two-part non-slumping paste having a UL Flammability Rating and a Relative Thermal Index greater than or equal to approximately 105° C. In addition, the fluid adhesive may also be resistive to the flow of electricity. For example, the fluid adhesive may have a volume resistivity that is greater than approximately 1×10 13 ohm*cm and a dielectric strength that is greater than 15 Kv/mm.
[0035] The fluid adhesive has a fluid consistency. For example, the fluid adhesive may have a viscosity in a range of approximately 10,000 centiPoise (cP) to approximately 200,000 cP at room temperature. A relatively fluid adhesive can provide higher bond strength between the conductor interface 250 and a photovoltaic module than is achieved with a typical solid adhesive, such as a foam tape.
[0036] Raised features 230 , 235 maintain a fixed gap between bottom surface 290 of base portion 205 and the module back surface 140 to which conductor interface 250 is bonded ( FIG. 1 ). For example, raised features 230 , 235 may both have a height of approximately 0.8 mm.
[0037] Raised features 230 , 235 may be spaced approximately 2 mm away from the respective connection cavities 270 , 275 and wire cavities 280 , 285 . The ends of raised features 230 , 235 extend partially but not completely to the edge of bottom surface 290 , to allow for a layer of adhesive material to be applied between raised features 230 , 235 and the edges of bottom surface 290 . For example, raised feature 230 may extend to approximately 11 mm from the edge of bottom surface 290 in which wire hole 260 is located, and raised feature 235 may extend to approximately 11 mm from the edge of bottom surface 290 in which wire hole 265 is located. Raised features 230 , 235 may have substantially uniform or varying widths along their respective lengths. For example, raised features 230 , 235 may be approximately 1.5 mm wide along their lengths.
[0038] Raised features 230 , 235 , in addition to providing a fixed space between bottom surface 290 the back surface 140 of photovoltaic module 10 ( FIG. 1 ) for a fluid adhesive material to occupy, also prevents the fluid adhesive from leaking into connection cavities 270 , 275 or wire cavities 280 , 285 . Adhesive leaking into connection cavities 270 , 275 can interfere with the electrical connection of external conductors 120 , 125 to internal conductors 410 , 415 ( FIG. 2 ). Adhesive leaking into wire cavities 280 , 285 may also come into contact with the external conductors 120 , 125 as they are inserted into the conductor interface 250 , resulting in the adhesive being transferred on the wires into the connection cavities 270 , 275 .
[0039] Raised features 230 , 235 also ensure that there is space between external conductors 120 , 125 and the back surface 140 of the module 10 to which conductor interface 250 is bonded ( FIG. 1 ). This allows potting material used to fill conductor interface 250 to completely surround external conductors 120 , 125 . For example, longer sections of external conductors 120 , 125 can be completely surrounded by potting material, providing a more robust seal to prevent moisture ingress and electrical leakage. Furthermore, the open space beneath internal conductors 120 , 125 that is provided by the raised features 230 , 235 ensures that potting material also contacts the surface of module 10 to which conductor interface 250 is bonded, thereby creating an even stronger and better sealed bond between conductor interface 250 and the module surface. In addition, the fixed space provided by raised features 230 , 235 creates a predetermined volume to be filled by the potting material, such as the volume within cavities 270 , 275 , 280 , 285 and between these cavities and the back surface 140 of the module 10 , which helps to ensure complete potting material fillage and facilitates automation of the manufacturing process by allowing a fixed amount of potting material to be used.
[0040] As shown in FIGS. 5 and 6 , base portion 205 may also include raised features 240 , 245 at opposing corners of bottom surface 290 to provide greater stability when conductor interface 250 is mounted to a module 10 . Raised features 240 , 245 may be approximately the same height as raised features 230 , 235 . For example, raised features 230 , 235 , 240 , 245 may all have a height of approximately 0.8 mm. Raised features 240 , 245 may have a circular surface area, as shown in FIGS. 5 and 6 , or have other shapes, such as an elliptical or polygon shape. In one example, raised features 240 , 245 may have circular surface areas with radii of approximately 0.25 mm. Raised features 240 , 245 are located at a distance from the opposing corners of bottom surface 290 sufficient to allow for a layer of adhesive material to be applied between raised features 240 , 245 and the edges of bottom surface 290 . For example, raised features 240 , 245 may be located in a range of at least 5 to 10 mm from the opposing corners of bottom surface 290 .
[0041] One or more of raised features 230 , 235 , 240 , 245 may also have a secondary adhesive material, such as a quick bonding hot or room temperature adhesive, a pressure-sensitive adhesive material, or a dual-sided foam tape, affixed to its surface. The secondary adhesive on one or more of raised features 230 , 235 , 240 , 245 can be used to hold base portion 205 in place on a module to which it is mounted while the fluid adhesive cures and solidifies.
[0042] FIG. 7 shows a bottom perspective of another embodiment of a base portion 205 b for conductor interface 250 . Base portion 205 b includes similar features as base portion 205 discussed in connection with FIGS. 5-6 , including raised features 230 , 235 , 240 , 245 . In addition, bottom surface 290 b of base portion 205 b includes a surface texture 295 to enhance the bond strength of the fluid adhesive applied to bottom surface 290 b . The surface texture 295 may be, for example, a random surface character or other roughness character having a depth in a range of 25 μm to 100 μm, and can be applied by the injection molding process during the formation of conductor interface 250 . The surface texture 295 may be applied to substantially all of bottom surface 290 b , or to a portion of bottom surface 290 b.
[0043] FIG. 8 shows a bottom perspective of base portion 205 b with fluid adhesive 292 applied to bottom surface 290 b . As described above, fluid adhesive 292 may be a non-slumping paste with a fluid consistency. Fluid adhesive 292 may be, for example, a water, silicone, urethane, or epoxy-based one-part or two-part adhesive, which may be selected to have a high adhesive strength to glass and polycarbonate and a high intrinsic tensile strength, capable of withstanding damp heat conditions, having a high flammability rating, and electrically resistive.
[0044] The fluid adhesive 292 may be applied covering substantially all of bottom surface 290 b outside of raised features 230 , 235 , or alternatively may be applied covering a portion of bottom surface 290 b . For example, as shown in FIG. 8 , a layer of fluid adhesive 292 may be applied surrounding the perimeter of bottom surface 290 b . The layer of fluid adhesive 292 may be applied in a pattern with a diameter in a range of approximately 5 mm to 10 mm. When applied, the fluid adhesive will typically expand to cover a larger portion of bottom surface 290 b , and therefore should be applied with some distance, for example, 2 mm, from the edge of bottom surface 290 b to prevent adhesive from spreading beyond bottom surface 290 b and/or under wire holes 260 , 265 . If fluid adhesive 292 is a two-part adhesive, a resin portion may be applied first, and then a catalyst portion applied to the resin portion.
[0045] Multiple layers of fluid adhesive may be applied to bottom surface 290 b . For example, in addition to a layer of fluid adhesive 292 applied surrounding the perimeter of bottom surface 290 , addition layers of fluid adhesive 294 , 296 may be applied on inner areas of bottom surface 290 b , such as layer 294 applied between raised feature 235 and raised feature 240 , and layer 296 applied between raised feature 230 and raised feature 245 . The layers of fluid adhesive 292 , 294 , 296 may be applied using a hot or cold automated applicator or dispenser, through a manual application process, or through other known techniques. Similar arrangements for fluid adhesive 292 , 294 , 296 may also be applied to bottom surface 290 of base portion 205 ( FIGS. 5-6 ).
[0046] FIG. 9 shows a conductor interface 250 affixed to back surface 140 of a photovoltaic module 10 above an opening 405 exposing one or more internal conductors 410 , 415 ( FIG. 2 ). A secondary adhesive on the surface area of one or more of the raised features 230 , 235 , 240 , 245 ( FIG. 5 ) may be used to affix conductor interface 250 to surface 500 while a fluid adhesive bond is formed with the adhesive provided between the bottom surface 290 of conductor interface 250 . Conductor interface 250 includes base portion 205 and top portion 210 , although it should be understood that conductor interface 250 could instead include base portion 205 b discussed in connection with FIGS. 7-8 .
[0047] As shown in FIG. 9 , fluid adhesive 550 (e.g., from adhesive layers 292 , 294 , 296 of FIG. 8 ) fills the space between back surface 140 and conductor interface 250 that is maintained by raised features 230 , 235 , 240 , 245 ( FIGS. 5-8 ). The applied fluid adhesive is cured to form a bond between conductor interface 250 and back surface 140 , such as by allowing it to harden through exposure to air or other elements, applying a heat or cooling source, and/or other known types of curing treatments. Raised features 230 , 235 prevent fluid adhesive from entering connection cavities 270 , 275 and wire cavities 280 , 285 .
[0048] After conductor interface 250 is affixed to back surface 140 , external conductors 120 , 125 ( FIG. 6 ) may be inserted into wire holes 260 , 265 , where they can be electrically connected to internal conductors 410 , 415 ( FIG. 2 ) of the photovoltaic module 10 , for example by welding or soldering the terminal portions 122 , 127 of external conductors 120 , 125 to internal conductors 410 , 415 prior to affixing cover portion 210 to base portion 205 , or by welding or soldering the terminal portions 122 , 127 to internal conductors 410 , 415 through openings 272 , 274 when base portion 205 and cover portion 210 are formed as a single piece. Alternatively, external conductors 120 , 125 may be inserted into wire holes 260 , 265 and electrically connected to internal conductors 410 , 415 prior to affixing conductor interface 250 to back surface 140 .
[0049] After electrical connection is made between the external conductors 120 , 124 and internal conductors 410 , 415 , connection cavities 270 , 275 and wire cavities 280 , 285 are then filled with potting material, for example through openings 272 , 274 or wire holes 260 , 265 . Together with fluid adhesive 550 , the potting material filling the cavities of conductor interface 250 electrically isolates the electrical connections and prevents moisture from entering into conductor interface 250 . Because raised features 230 , 235 form a fixed volume surrounding external conductors 120 , 125 , a known amount of potting material can be used to fill the cavities 270 , 275 , 280 , 285 . In addition, raised features 230 , 235 allow potting material to completely surround portions of internal conductors 120 , 125 within conductor interface 250 .
[0050] FIG. 10 shows a bottom perspective of another embodiment of a conductor interface 350 . Conductor interface 350 can be mounted adjacent to back surface 140 of a photovoltaic module 10 ( FIG. 1 ). Conductor interface 350 includes a base portion 305 and a top portion 210 . Base portion 305 can be mounted adjacent to a mounting surface, such as a back surface 140 of a photovoltaic module 10 . Top portion 210 has similar features as the top portion 210 discussed above in connection with FIG. 5 . Conductor interface 350 may be formed from plastic, metal, or other appropriate materials. For example, conductor interface 350 may be formed from a plastic or polycarbonate material shaped through an injection molding process.
[0051] Conductor interface 350 includes wire holes 260 , 265 through which external conductors 120 , 125 ( FIG. 6 ) can be inserted. Although two wire holes 260 , 265 are shown in FIG. 10 , it should be understood that a conductor interface 350 may have fewer or greater wire holes to accommodate the number of desired electrical connections.
[0052] The bottom surface 390 of conductor interface 350 includes respective connection cavities 270 , 275 and wire cavities 280 , 285 , which have similar features as connection cavities 270 , 275 and wire cavities 280 , 285 discussed in connection with FIGS. 5-9 . Bottom surface 390 of conductor interface 350 includes a raised feature 330 at an outer end of wire cavity 280 , and a raised feature 335 at an outer end of wire cavity 285 . As discussed further below, raised features 330 , 335 are arranged to, accommodate a secondary adhesive 380 ( FIG. 12 ), such as a dual-sided tape, that can be used to affix conductor interface 350 to a module surface while a fluid adhesive, such as a glue or paste, forms a bond between conductor interface 350 and the back surface 140 .
[0053] Raised features 330 , 335 may have similar heights and widths as raised features 230 , 235 discussed above in connection with FIGS. 5-9 . For example, raised features 330 , 335 may both have a height of approximately 0.8 mm, and may be approximately 1.5 mm wide along their lengths. Raised features 330 , 335 may be spaced approximately 2 mm away from the respective wire cavities 280 , 285 .
[0054] Raised features 330 , 335 provide a fixed space between bottom surface 390 of conductor interface 350 and a back surface 140 to which it is to be bonded. The fixed space forms a cavity for fluid adhesive material to bond conductor interface 350 to back surface 140 . Raised features 330 , 335 also help prevent the fluid adhesive from leaking into wire cavities 280 , 285 . As discussed in connection with FIGS. 5-9 , raised features 330 , 335 also ensure that there is space between external conductors 120 , 125 inserted into wire holes 260 , 265 and the back surface 140 , allowing potting material to completely surround external conductors 120 , 125 . Furthermore, the open space beneath external conductors 120 , 125 allows the potting material to also contact the back surface 140 .
[0055] Conductor interface 350 may also include raised features 340 , 345 at opposing corners of bottom surface 390 to provide added stability when conductor interface 350 is mounted to a module 10 . Raised features 340 , 345 may be approximately the same height and width as raised features 330 , 335 . Raised features 340 , 345 may have a horseshoe or other polygonal shape, or may have a circular surface area similar to raised features 240 , 245 discussed in connection with FIGS. 5 and 6 . Raised features 340 , 345 may be located at a distance from the opposing corners of bottom surface 390 sufficient to allow for a layer of adhesive material to be applied between raised features 340 , 345 and the edges of bottom surface 390 , or may be located at a lateral distance from wire and connection cavities 270 , 275 , 280 , 285 sufficient to allow for a layer of adhesive material to be applied between the cavities 270 , 280 and raised feature 345 , and for a layer of adhesive material to be applied between cavities 275 , 285 and raised feature 340 .
[0056] FIG. 11 shows a bottom perspective of another embodiment of a base portion 305 b for conductor interface 350 . Base portion 305 b includes similar features as base portion 305 discussed in connection with FIG. 10 , including raised features 330 , 335 , 340 , 345 . In addition, bottom surface 390 b of base portion 305 b includes an area 392 in which a fluid adhesive can be applied, and an area 394 in which a secondary adhesive material 380 ( FIG. 12 ), such as a pressure-sensitive adhesive material or a dual-sided foam tape, can be affixed to bottom surface 390 . Area 392 in which the viscous material can be applied may have a surface texture 395 to enhance the bond strength of the fluid adhesive, such as a random surface character or other roughness character having a depth in a range of 25 μm to 100 p.m. Area 394 may be substantially flat to accommodate a dual-sided foam tape or pressure-sensitive adhesive.
[0057] FIG. 12 shows a bottom perspective of base portion 305 b with secondary adhesive 380 applied over area 394 ( FIG. 11 ) of bottom surface 390 b . As discussed above, secondary adhesive 380 may be, for example, a dual-sided foam tape or a pressure-sensitive adhesive. Secondary adhesive 380 can be used to hold conductor interface 350 in place on a back surface 140 to which it is mounted while the fluid adhesive 396 , 397 , 398 , 399 ( FIG. 13 ) cures and solidifies. Secondary adhesive 380 has a thickness that is approximately the same or greater than the height of raised features 330 , 335 , to permit secondary adhesive 380 to make contact with the back surface 140 of a module 10 , and to serve as a barrier to prevent the fluid adhesive from entering connection cavities 270 , 275 and wire cavities 280 , 285 . Secondary adhesive 380 includes openings to expose connection cavities 270 , 275 , in order to permit electrical connection of external conductors 120 , 125 ( FIG. 6 ) inserted into wire openings 260 , 265 with respective internal conductors 410 , 415 ( FIG. 2 ). Secondary adhesive 380 is shaped to permit a fluid adhesive to be applied on area 392 of bottom surface 390 b.
[0058] FIG. 13 shows a bottom perspective of base portion 305 b with a secondary adhesive 380 applied to area 394 ( FIG. 11 ) of bottom surface 390 b and fluid adhesive applied to area 392 of bottom surface 390 b . For example, layers of fluid adhesive 396 , 397 , 398 , 399 may be applied surrounding the perimeter of bottom surface 390 b . The layers of fluid adhesive 396 - 399 may be, for example, applied with a width in a range of approximately 5 mm to 10 mm. When applied to back surface 140 , the fluid adhesive will typically expand to cover a larger portion of area 392 , and therefore should be applied with some distance, for example, 2 mm, from the edge of bottom surface 390 b.
[0059] Details of one or more embodiments are set forth in the accompanying drawings and description. Other features, objects, and advantages will be apparent from the description, drawings, and claims. It should also be understood that the appended drawings are not necessarily to scale, presenting a somewhat simplified representation of various features and basic principles of the invention. Although a number of embodiments of the invention have been described, it will be understood that various modifications may be made without departing from the spirit and scope of the invention.
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Described embodiments provide a conductor interface for a photovoltaic module that includes a raised feature on a bottom surface. Methods of forming such structures are also disclosed, as are photovoltaic modules containing the conductor interface.
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FIELD OF THE INVENTION
[0001] This invention relates to an apparatus and method for measuring the thickness of mold components during a manufacturing process. In particular, the present invention uses fiber optic interferometry to measure the center thickness of ophthalmic lenses.
BACKGROUND OF THE INVENTION
[0002] Ophthalmic lenses may be created using a variety of methods, one of which includes molding. In a double sided molding process, the lenses are manufactured between two molds without subsequent machining of the surfaces or edges. Such mold processes are described, for example in U.S. Pat. No. 6,113,817, which is expressly incorporated by reference as if fully set forth herein. As such, the geometry of the lens is determined by the geometry of the mold. Typical molding systems include cast molding, which involves using two mold halves, and spin-casting. These methods may also be combined with other machining techniques to create specific lens designs. Another process involves cycling lenses through a series of stations on a semi-continuous basis. The cyclic portion of lens production generally involves dispensing a liquid crosslinkable and/or polymerizable material into a female mold half, mating a male mold half to the female mold half, irradiating to crosslink and/or polymerize, separating the mold halves and removing the lens, packaging the lens, cleaning the mold halves and returning the mold halves to the dispensing position. Once a mold is designed and fabricated it must be measured to ensure that it meets the proper specifications. Typical molds may be spherical or non-spherical, depending upon the type of lens to be created. Because most molds have one or more arcuate surfaces, linear coordinates may be unable to measure a curved surface accurately or may only be able to accurately measure portions of the mold geometry. Additionally, current measurement means such as Michelson interferometers may be adapted for use in a lab but may not be practical or efficient for use on a manufacturing line due to vibration and other types of interference/noise that may affect sensitive equipment.
[0003] An interferometer is a measurement instrument that utilizes optical interference to determine various characteristics of optical surfaces. Interferometers typically generate a precise monochromatic wavefront, such as that of a laser, and split it using a beam splitter. The resulting two wavefronts include a test wavefront and a reference wavefront. These wavefronts are passed through a sample and a reference optical system, respectively, to create interference fringes which may then be measured. Methods for measuring the thickness of a material using interferometers are known in the prior art. For example, U.S. Pat. No. 3,319,515 (Flournoy) relates to the determination of thickness on the basis of interferometric optical phase discrimination and is expressly incorporated by reference as if fully set forth herein. U.S. Pat. No. 5,473,432 (Sorin) and U.S. Pat. No. 5,610,716 (Sorin et al) relate to an apparatus and method for measuring film thickness of a moving film, employing optical reflectrometry, both of which are expressly incorporated by reference as if fully set forth herein.
SUMMARY OF THE INVENTION
[0004] The present invention seeks to provide a non-destructive, non-contact method and apparatus for determining mold thickness.
[0005] These and other aspects of the invention will become apparent from the following description of the preferred embodiments taken in conjunction with the following drawings. As would be obvious to one skilled in the art, many variations and modifications of the invention may be effected without departing from the spirit and scope of the novel concepts of the disclosure.
[0006] The present invention includes a method for determining the thickness of a sample that has one or more boundaries that reflect light. Such a method may include providing one or more interferometers supplied with a coherent light source and a non-coherent light source and positioning the contact lens such that the non-coherent light source is incident upon the sample; and obtaining measurements of the contact lens thickness as generated by interference fringes created by the interferometer. This method is designed to be used on a manufacturing line so that contact lenses or contact lens mold thickness may be determined. In one embodiment of the present invention, the method may also include analyzing the interference fringes. In another embodiment of the present invention, the method may include positioning the sample above the non-coherent light source. The sample may also be positioned below the coherent light source.
[0007] In the present invention the one or more interferometers may be fiber-optic interferometers. In an embodiment in which interference fringes are analyzed, the analysis may include calculating distance using optical path and group index. In the positioning step of the present invention, it may be desirable to position the sample lens such that the non-coherent light source is incident upon the sample. In still another embodiment, the positioning step may include placing a probe within about 5 degrees normal to the surface to be measured. Additionally, it may be preferable to have a substantially constant distance between the sensor and the sample. In a related embodiment, the sensor may be aligned over the center of the lens or lens mold prior to the positioning step.
[0008] The interference fringes of the present invention may be generated by light reflecting off of the boundaries between: a medium and the lower surface of a female mold; the upper surface of the female mold and the lens material within the assembled mold; the lens material within the assembled mold and the lower surface of a male mold; and the upper surface of the male mold and the medium. In related embodiments medium may be air or saline. The present invention may also include alignment process that aligns the interferometer probe with the center of the sample.
[0009] In the obtaining step of the present invention, the obtaining step may include converting an optical path distance to material thickness. Converting the optical path distance may comprise measuring the optical path distance; and dividing the optical path distance by the group index of the material.
[0010] The present invention may include an apparatus that is related to the method. This apparatus may include one or more movement stages connected to a lens measurement system; a means for calculation, and a lens measurement system that contains a housing that holds a sample lens, wherein the lens measurement system is connected to the movement stages via a support post. The lens measurement system may include a light source and a fiberoptic interferometer. The apparatus, similar to the method, may include a means for aligning the fiber optic interferometer with the sample lens. In a related embodiment, the means for calculation may include a computer that, in conjunction with the interferometer, is capable of determining the group index of a material.
DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 depicts a typical Michelson interferometer.
[0012] FIG. 2A depicts an apparatus used in one embodiment of the present invention.
[0013] FIG. 2B is a detail drawing of a lens measurement system used in the apparatus of FIG. 2A .
[0014] FIG. 3 is a detail drawing of a cold mirror setup that may be used in conjunction with the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0015] Reference now will be made in detail to the embodiments of the invention. It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope or spirit of the invention. For instance, features illustrated or described as part of one embodiment, can be used on another embodiment to yield a still further embodiment. Thus, it is intended that the present invention cover such modifications and variations as come within the scope of the appended claims and their equivalents. Other objects, features and aspects of the present invention are disclosed in or are obvious from the following detailed description. In particular, the terms male mold and male mold half may be used interchangeably. The terms female mold and female mold half may also be used interchangeably. Additionally the term “sample” refers to a lens sample and/or a mold sample. It is to be understood by one of ordinary skill in the art that the present discussion is a description of exemplary embodiments only, and is not intended as limiting the broader aspects of the present invention.
[0016] The present invention comprises an apparatus and method to more accurately measure the thickness of a mold assembly (an assembled male and female mold). In a preferred embodiment, the present invention is able to measure the center thickness (CT) of the male mold, the female mold, and/or the polymer between the molds. The invention comprises a fiber optic sensor and related methods and fixtures for orienting the fiber optic sensor normal to the surfaces of interest.
[0017] The present invention uses the principle that light incident on a translucent or semi-translucent film reflects a portion of that light. If there are multiple surfaces, each surface interface (boundary) will cause some amount to be reflected, dependant upon material properties. For example, a female mold will have two reflections—one from the lower surface and one from the upper surface (the surface that contacts the polymer). It is important to remember, however, that the light is not reflecting from the surface, but rather the boundary between two areas with a change in refractive index of over about 0.01. In an assembled mold, with or without polymer, there will be four reflections: one from the lower surface of the female mold half (the boundary between the air and the lower surface of the female mold half, one from the upper surface of the female mold half (the boundary between the upper surface of the female mold half and the material within the assembled mold), one from the lower surface of the male mold half (the boundary between the material within the assembled mold and the lower surface of the male mold half) and one from the upper surface of the male mold half (the boundary between the upper surface of the male mold half and the air). The reflections measure the thickness of the mold assemblies based upon the optical distance that the reflections have traveled. It is believed that because the sensor is fiber optics-based, it is not easily affected by vibration. Hence, the present invention uses the above fiber optic interferometer technology in conjunction with specific fixturing and manufacturing methods to reduce manufacturing noise that affects the accuracy of interferometric measurement.
[0018] A complete description of the fiber optic sensor technology is described in U.S. Pat. Nos. 6,038,027; 6,067,161; 5,596,409; and 5,659,392, all of which are incorporated by reference as if fully set forth herein. A representative system that uses these principles is made by Lumetrics, Inc. (West Henrietta, N.Y.). In accordance with the present invention, a fiber optic interferometer may be used to determine the thickness of a contact lens or associated molds.
[0019] An exemplary interferometer apparatus 20 is preferably a dual interferometer apparatus of a Michelson configuration in an autocorrelation mode, as shown in FIG. 1 . Optical probe 18 directs a beam of light from a non-coherent light source 30 (such as light-emitting diode (LED) toward a sample. Optical probe 18 may include includes a Gradient Index lens (e.g., GRIN). The light is reflected from boundaries, as described later in the present application. In a particular embodiment, the light may be reflected on the front F and back B surfaces of the contact lens and the light signals may be introduced into two arms of interferometer apparatus 20 through an optical coupler 32 and a fiber collimator 34 (shown in FIG. 3 ). A coherent light source 36 (such as a HeNe laser) emits a beam of light toward a beam splitter 38 . Beam splitter 38 divides the beams of light into pairs of light beams directed toward a pair of hollow-cube retroreflectors 40 , 42 which are mounted 90 degrees apart and move in perpendicular directions as shown by arrows B and C. The outputs of interferometer apparatus 20 are directed to a pair of detectors 44 , 46 for LED 30 and laser 36 , respectively. The non-coherent light of LED 30 follows the same light path as the coherent light path of HeNe laser 36 , but in reverse time order. A band-pass filter 48 blocks the light from laser 36 being incident on material M. A second filter 50 prevents light from LED 30 from interfering with the light from laser 36 . As such, the laser interferometer tracks the distance the optical path has changed, with the laser signal providing data acquisition trigger signals, at constant distance intervals, for collecting interferometric data from the LED interferometer. Therefore, the purpose of the laser interferometer is to track the distance the optical path moves while the LED interferometer is collecting data from the boundaries of the sample.
[0020] The above-described system measures the optical path. To convert the optical path distance (OPD) to actual material thickness, the measured OPD must be divided by the group index or group velocity of the material. The group index is a material property, is related to the refractive index, and is described at http://www.mathpages.com/home/kmath210/kmath210.htm. The difference in group index between materials must be approximately larger than 0.01 in order for the instrument to detect the reflection. In an embodiment in which the sample is a lens inside of a mold, the lens polymer would have a different group index than the polypropylene mold halves.
[0021] The light used by the sensor may be visible, UV, IR, or any other wavelength of radiation that will reflect off the surfaces of interest. Due to the small tolerance on the angle of reflectance, the sample is preferably substantially normal (about 5 degrees from perpendicular) relative to a light emitting probe (fiber optic interferometer) to pick up the return signal. The probe may act as a lens focusing system that shapes the light from the fiber optic interferometer into a useful form. Additionally, the optics of the interferometer probe will preferably determine the distance of the sample from the light-emitting aperture on the interferometer probe. For example, if points other than those located near the center are to be scanned, the sample or the interferometer probe is preferably moved in a way that keeps the orientation of the interferometer probe and sample constant to within the tolerance of the instrument. Changes in the thickness profile of the sample may further reduce the acceptable angle to receive a signal. In an alternative embodiment, the slim tolerance of the signal acceptance angle may be overcome by providing a plurality of interferometer probe heads to measure specific points of interest on the mold. In this embodiment one interferometer probe may be used for each point. The mold surfaces may be optimized to increase the signal by reducing loses in the transmitted light at the air/mold interface (with an anti-reflection coating), creating an equal thickness mold, or optimizing the curve of the mold and/or the motion of the interferometer probe.
[0022] In a specific embodiment the measurement device may be located above or below a contact lens or contact lens mold sample on the manufacturing line. The present invention also allows measurement of a hydrated lens. The measurement device is preferably adapted to measure both the lens height and the center thickness.
[0023] An exemplary setup is shown in FIG. 2 . Specific manufacturers and models of components of the present invention are exemplary only and are not intended to be limiting. Referring to FIG. 2A , an apparatus of the present invention preferably comprises at least one linear movement stage 16 . Stage 16 preferably provides about 25 mm of total travel and is adapted to connect to a controller. In some embodiments, two stages may be used (one for vertical movement and one for horizontal movement). A recommended stage is MFA-CC from Newport and a coordinated controller may be a Newport ESP300 controller. In an embodiment with two stages, the lower stage is preferably a LINOS mounting base with adjustable support feet. The lens measurement system, pictured in FIG. 2B , sits about the linear movement stages and houses the lens, the wetcell 1 that holds the lens, and optical measurement devices and supports. Wetcell 1 preferably has an optically clear top and bottom (for both visible and infrared light). Beneath wetcell 1 is a wetcell support platform 2 . The backbone of the lens measurement system is preferably a support post 3 , such as, for example a LINOS X95 rail, which is preferably about 500 mm in length. The lens measurement devices or components are attached to support post 3 by a carrier 4 such as a LINOS carrier 50-X95.
[0024] Light source 5 is also a component of the lens measurement system. Light source may be a single white LED with a plurality of collimating lenses held in an aluminum cylinder or any optical equivalent. Bracket 6 preferably provides a physical connection between backlight 5 and support post 4 . The cold mirror 8 is located preferably about 45 degrees to both the light source 5 and the lens sample. Cold mirror 8 is preferably mounted to wetcell support platform 2 via mounting adapter 7 . Cold mirror 8 may be a 31.55 mm mirror, such as LINOS part no. 38-0255 035. Focus lens 9 is used to focus the beam from the interferometer probe. The beam preferably comes through collimator 11 through focusing lens 9 . Lens 9 preferably has about a 50 mm focal length. Lens 9 is connected to adjustable mount 10 , which allows a user to move the lens in 2 directions +/− about 1 mm. An exemplary mount is made by LINOS, part 06-1025. Fiber optic collimator 11 collimates the beam from the fiber optics cable, which is part of the interferometer Referring back to FIG. 2A , a high resolution camera 12 is preferably located at the top of support post 3 . A cooling fan 13 may be located in close proximity to camera 12 to prevent camera 12 from overheating. The present invention may also include a 0.5× telecentric lens 14 for camera 12 . Telecentric lens 14 may be mounted via mounting bracket 15 . Telecentric lens 14 may be used to measure the diameter of the lens or other sample characteristics to detect the presence of the beam. Telecentric lens 14 may also be used to eliminate optical errors such as parallax.
[0025] Because the measurement of the lens is limited to surfaces which are nearly normal to the probe, a method is needed to align the interferometer probe with the center of the sample. This is important for accurate CT measurement and guarantees that the read CT value is collected from the center of the lens. One method of aligning the probe with the center of the lens or mold is to view the lens or mold from the top with a digital camera. In this embodiment, shown in FIG. 3 , the interferometer probe is inverted and placed under the lens or mold and pointed upward to the sample. The sample in wetcell 30 may be lit by a light source 36 in a way that allows the camera to see and measure the outer diameter and calculate the center of the sample in relation to the camera. An example of a preferred light source is a collimated backlight. This requires a cold mirror, depicted in FIG. 3 as element 32 , which reflects visible light but transmits IR. A cold mirror is a special filter that reflects visible light (˜350-700 nm) and transmits IR light (˜800-2500 nm). It is designed to be used at an angle that exhibits the best transmission/reflection, which may be about 45 degres. In an embodiment in which a 45 degree angle is used, the backlight and the IR beam are preferably at a 45 deg angle to the cold mirror, as shown in FIG. 3 . The cold mirror preferably allows combination of the IR and backlight beams without the losses of a beam splitter. Element 33 is a focusing lens that focuses light.
[0026] The backlight 36 is preferably placed perpendicular to the beam 35 and is reflected normal to the sample by the cold mirror 32 which may be mounted approximately 45 degrees to both the light source 36 and the sample. The direction of IR beam 35 preferably remains constant as it passes through cold mirror 32 . A computer compares the position of the interferometer probe with the center of the lens or mold. In an embodiment in which the interferometer probe is attached to a motion system, the computer preferably directs the interferometer probe to the center of the lens or mold. An example of a possible motion system is two MFA-CC linear stages (Newport, Inc) mounted in an XY configuration, which may be controlled by an ESP300 Motion Controller/Motion Driver (Newport, Inc). The ESP300 is preferably connected to a PC through an RS-232 cable.
[0027] In an embodiment in which a camera is used that is sensitive to 1.3 micron light (IR), the beam from the interferometer probe preferably registers on the camera sensor. An example of this type of camera is a PL-A782 from PixeLink. Using an IR-sensitive camera preferably allows the system to move the interferometer probe to the center of the lens in a closed-loop feedback system. The position of the probe is verified by the position of the beam “dot” from the interferometer probe relative to the calculated sample center.
[0028] In a hydrated embodiment, the center thickness (CT) of the lens or mold may be measured directly by the reflected light. For example, in an embodiment in which the sagittal height of the lens is desired, a reference may be used. If the lens is placed in a wetcell that is full of saline, the outer diameter (typically known as the edge flat) of the lens rests on the bottom surface of the wetcell. The light is first reflected from the top and bottom of the wetcell surface, returning a thickness value for the wetcell wall. The next reflecting surface is the bottom of the lens. The difference between the bottom of the lens and the top of the wetcell wall form a thickness which corresponds to the posterior sagittal height (Psag) of the lens. This is critical because the interferometer does not measure distances, only differences in distance (thickness), as previously described. Without a reference, it is not possible to gauge Psag. The next reflecting surface is the top of the contact lens, which provides the CT measurement and the anterior sagittal height (Asag). This is advantageous because base curve equivalent (BCE) calculations rely on the Psag, which is typically derived from the Asag and CT.
BCE = - ( ( Diameter - 2 ( edgeflat ) 2 4 ) + Psag 2 ) 2 / Psag
[0029] Now, these values can be measured directly removing an additional source of error in the BCE calculation. In addition, the thickness of the wetcell wall should be constant. Any change in the value of the wetcell thickness for the same wetcell would indicate an error in the system. Hence, the original measured wetcell thickness serves as a reference. Additionally, this property can be used to identify individual wetcells. The interferometer is accurate to about 0.1 um in such a situation. The thickness of most wetcells varies significantly more than this value.
[0030] As mentioned above, to obtain the actual lens CT in microns, the group index of the lens material must be known. The group index of the material may be a limitation on the accuracy of the instrument because the lens CT is always the measured OPD/group index. However, with the wetcell setup as mentioned above, it is possible to measure the real thickness directly and simultaneously calculate group index for each sample.
[0031] In a hydrated embodiment, the procedure first involves calculating the group index (GI) of the saline. This is accomplished by measuring a wetcell in which the gap inside of the cell can be measured by the instrument. Because the GI of air=1, the OPD=real thickness. The wetcell is then filled with saline and the OPD of the gap is measured again. The OPD of the gap will be increased due to the presence of the saline. The GI is equal to the OPD air/OPD saline.
[0032] Once the GI of the saline is known, the lens is placed in the cell. There will be three distances measured between the cell walls: the gap below the lens (cell wall to bottom of the lens), lens thickness, and the gap above the lens (top of the lens to the top of the cell). The top and bottom gap are filled with saline, so those thickness can be converted accurately. These two thicknesses can be subtracted from the total wetcell gap without the lens to calculate the lens thickness. This thickness must be divided by the GI of the saline to calculate the real lens thickness. The measured OPD can be divided by this value to calculate the GI for the lens material. This means that the real center thickness measurement is independent of the GI of the lens material. It only depends on an accurate measurement of the GI of the saline. In this calculation, the lens height (PSag) is solely dependent on the GI of the saline since it is equal to the bottom gap.
[0033] It is useful to note that the OPD for each layer (cell wall, lens thickness, PSag) is preferably calculated from the reference, not between peaks on the interferometer. For example, the first peak from the interferometer represents the lens CT because this is the smallest thickness. The next peak represents the cell walls since it is the 2 nd thinnest. The third peak represents the PSag. The OPD for the PSag is OPD from the reference peak all the way to the third peak, rather than the distance between the 2 nd and 3 rd peak. For PSag, this total OPD would be divided by the GI of the saline. The lens CT would be the OPD from the reference to the 1 st peak, divided by the GI of the lens material, unless the thickness is calculated as described above.
[0034] In addition, the optical setup may be changed without affecting the function. The probe and/or camera may be placed either above or below the sample. If the probe is placed above the lens, the PSag is then calculated as the gap “above” the lens. Also, the camera may be placed perpendicular to the cold mirror and the backlight opposite to the camera and probe. Finally, the lens may be lit in other ways such as a ring light, diffuse LED source, or other equivalent lighting techniques. A similar technique may also be used for measuring lens thickness.
[0035] The invention has been described in detail, with particular reference to certain preferred embodiments, in order to enable the reader to practice the invention without undue experimentation. A person having ordinary skill in the art will readily recognize that many of the previous components, compositions, and/or parameters may be varied or modified to a reasonable extent without departing from the scope and spirit of the invention. Furthermore, titles, headings, example materials or the like are provided to enhance the reader's comprehension of this document, and should not be read as limiting the scope of the present invention. Accordingly, the invention is defined by the following claims, and reasonable extensions and equivalents thereof.
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This invention relates to an apparatus and method for measuring the thickness of mold components and/or lenses during a manufacturing process. In particular, the present invention uses fiber optic interferometry to measure the center thickness of ophthalmic lenses created by a double-sided molding process.
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CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a national stage application under 35 U.S.C. 371 of International Patent Application Serial No. PCT/EP2010/006906, entitled “Process and Burner for Producing Synthesis Gas,” filed Nov. 12, 2010, which claims priority from German Patent Application No. 10 2010 004 787.2, filed Jan. 16, 2010, the disclosures of which are hereby incorporated by reference herein in their entirety.
FIELD OF THE INVENTION
This invention relates to a process and a burner for producing synthesis gas by partial oxidation of liquid or gaseous, carbonaceous fuel in the presence of an oxygen-containing oxidant, wherein the fuel, the oxidant and a moderator are separately supplied to a burner and wherein the fuel and the moderator are mixed in a mixing chamber of the burner, before they are brought in contact with the oxidant.
BACKGROUND OF THE INVENTION
Hydrogen-containing gas mixtures generally are referred to as synthesis gases, which are employed in various synthesis reactions. Examples include the methanol synthesis, the production of ammonia by the Haber-Bosch process or the Fischer-Tropsch synthesis. Synthesis gases can be produced from solid, liquid or gaseous starting materials.
Processes and apparatuses for producing synthesis gas are known in principle in the prior art. For example, a number of different technical approaches exist, in which liquid or gaseous, carbonaceous fuels with a moderator consisting of steam, carbon dioxide or a mixture thereof are partially oxidized with an oxygen-containing gas. The outlet opening of the used burner is directed into a combustion chamber.
WO 2008/065182 A1 discloses a process for producing synthesis gas, in which a burner is provided with a plurality of nozzle openings, so that a hydrocarbon fuel is guided through the burner separate from an oxidizing gas. The hydrocarbon fuel and the oxidizing gas are separated from each other by a lead-through for a moderator gas. The exit velocity of the moderator gas is greater than the exit velocity of the oxidizing gas.
U.S. 2003/0085385 A1 describes a process in which the reactants hydrocarbon fuel, steam, oxygen and recycled water are guided to the nozzle of a four-stream injector in separate channels. By means of the arrangement, a better conversion of the hydrocarbon fuel should be achieved.
In the process for producing synthesis gas known from WO 95/32148 A, nozzle corrosion should be avoided in that hydrocarbon fuel and oxidant run away from the nozzle in parallel separated by a moderator and there is no mixing of moderator and fuel.
In these known burners at least three outlet openings are present at the burner throat and the atomization of the fuel is effected outside the burner. In the case of an external atomization of the fuel, high relative velocity differences of the reactants exiting adjacent to each other are necessary at the burner throat, in order to perform the necessary atomization work. These high exit velocities of the moderator and/or of the oxidant generate extensive reaction zones. In addition, a high input of energy takes place via the conveying devices (e.g. pumps). Therefore, the nozzle outlet openings must be cooled in particular under transient conditions, such as in start-up and shut-down operations. In the prior art, a great problem also is premature material wear or the removal of material at the burner throat.
In the process for producing synthesis gas by partial oxidation of liquid or gaseous fuels in the presence of oxygen, which is described in DE 101 56 980 B4, the fuel, the oxygen-containing gas and an atomizing medium are separately supplied to the burner, and the atomizing medium is expanded via one or more nozzles directly before the central orifice opening for the fuel. The oxygen-containing gas is guided past the outside of the atomizing nozzle and enters the reactor space concentrically around the mixture of fuel and atomizing medium. This results in exothermal reactions in the vicinity of the burner head, which under transient conditions leads to a great thermal load of the reactor wall in the region of the burner.
SUMMARY OF THE INVENTION
Against this background it is the object underlying the invention to propose an alternative burner which in particular in operation with transient conditions is exposed to smaller loads.
In a process as mentioned above, this object substantially is solved by the invention in that the oxidant is centrally introduced through an outlet opening of the burner into a combustion chamber and that the mixture of fuel and moderator is introduced through the outlet opening into the combustion chamber concentrically around the oxidant.
Surprisingly, it was found that by reversed media guidance as compared to the prior art the temperature distribution in the reaction space can be influenced favorably and hence the thermal load of the reactor wall and the burner components is reduced. By guidance of the media in accordance with the invention, the oxidant (oxygen, air) is shielded against the synthesis gas present in the combustion chamber.
As a result, exothermal reactions in the vicinity of the burner throat can be suppressed.
To achieve a sufficient atomization and intermixing with the fuel, it is proposed in accordance with a development of the invention to inject the moderator into the mixing chamber with a velocity of 30 m/s to 200 m/s, preferably 80 m/s to 140 m/s. Advantageously, steam, carbon dioxide or a mixture thereof, possibly by adding a combustible gas, is used as moderator.
In accordance with the invention, intermixing with the moderator is promoted in that the fuel is guided towards the moderator jet at an angle β of 10° to 80°, preferably 40° to 60°, with respect to the burner axis. To achieve an efficient atomization, the exit velocity of the mixture of fuel and moderator from the mixing chamber is 30 m/s to 100 m/s, in accordance with one aspect of the invention.
In accordance with a development of the invention it is provided that the fuel is supplied to the combustion chamber through several burners, which can be integrated in a common housing. In accordance with the invention the possibility exists to supply a different fuel to each burner and thereby selectively influence the reaction conditions in the combustion chamber.
The present invention also relates to a burner for producing synthesis gas, which is suitable for performing the process of the invention. Such burner includes a central supply channel for supplying the oxidant, a mixing chamber surrounding the central supply channel, into which the supply conduits for the fuel and a moderator open, and an outlet duct via which the mixture of fuel and moderator from the mixing chamber is supplied to an outlet opening of the burner. In accordance with the invention, the outlet duct is concentrically arranged around the central supply channel for the oxidant.
To accelerate the moderator, the supply conduit for the moderator preferably opens into the mixing chamber via a constricted annular gap.
In accordance with a development of the burner of the invention, the supply conduit for the fuel meets with the moderator jet guided coaxially with respect to the central supply channel for the oxidant at an angle β of 10° to 80°, preferably 40° to 60°, with respect to the burner axis. In the mixing chamber, the liquid fuel thereby is intensively mixed with the moderator, wherein it is divided into fine/small droplets.
Preferably, the outlet duct tapers towards the outlet opening. The atomized fuel thereby is deflected towards the central oxidant jet and in addition accelerated once again shortly before exiting into the combustion space. Due to the taper of the outlet opening, wetting of the outer fuel duct wall necessarily is effected, so that the same is intensively cooled by the fuel.
In accordance with a development of the invention, an angle γ of the outer fuel duct wall with respect to the burner axis and an angle δ of the inner fuel duct wall with respect to a line parallel to the burner axis are chosen such that the angle γ is greater than the angle δ. Both angles preferably lie in the range from 0 to 20° and in particular between 0 and 10°.
In accordance with a preferred aspect of the invention the central supply channel for the oxidant is expanded in the region of the outlet opening with an angle α of 0° to 45°, preferably 0° to 10°, with respect to the burner axis, in order to achieve a broadened injection into the combustion space.
In accordance with the invention, the burner is surrounded by a cooling-water jacket. When several burners are provided, the same can also be jacketed together.
Further developments, advantages and possible applications of the invention can also be taken from the following description of embodiments and the drawing. All features described and/or illustrated form the subject-matter of the invention per se or in any combination, independent of their inclusion in the claims or their back-references.
BRIEF DESCRIPTION OF THE FIGURE
FIG. 1 shows part of a burner of the invention in a schematic sectional representation.
DETAILED DESCRIPTION
The burner 1 partly shown in the drawing includes a central supply channel (tube) 2 through which the oxidant, preferably technically pure, compressed and preheated oxygen, is delivered to the outlet opening 3 in the burner base plate 4 . In the front region of its orifice into the non-illustrated combustion chamber of the reactor for producing synthesis gas, the central supply channel 2 is slightly expanded with an angle α of 0° to 45°, preferably 0° to 10°, with respect to the burner axis A. Hence, the largest inside diameter of the central supply channel 2 is achieved at the orifice into the combustion chamber. Depending on the application, the exit surface offered by the central supply channel 2 for the oxidant each is calculated such that an exit velocity of the oxidant of 40 m/s to 140 m/s, preferably 60 m/s to 100 m/s, is realized.
Coaxially to the central oxidant supply through the supply channel 2 , the moderator is guided via a supply conduit 5 to a two-component atomizing nozzle 6 . The moderator consists of steam, carbon dioxide or a mixture thereof. If necessary and available, a combustible gas can also be added to the moderator. In the atomizing nozzle 6 , the moderator is accelerated by an annular gap 7 such that it reaches velocities of 30 m/s to 200 m/s, preferably 80 m/s to 140 m/s. These values are calculated for pure steam as moderator. When using carbon dioxide, a mixture of steam and carbon dioxide, or when admixing a combustible gas, the velocity to be achieved and hence the gap size of the annular gap 7 is calculated corresponding to the pulse flow of pure steam with the indicated velocity range to be achieved.
In downstream direction, the moderator accelerated in the annular gap 7 enters into a mixing chamber 8 surrounding the central supply channel 2 , where it meets with a laterally supplied fuel jet. As fuel, liquid or gaseous carbonaceous media are used, e.g. fuel oil or natural gas. The term liquid in the sense of the present invention also covers suspensions (slurries) in which solids are suspended in the liquid.
In the upper part of the burner 1 , the fuel jet initially is guided coaxially to the moderator through a supply conduit 9 , before it enters into the mixing chamber 8 through a bore or conical supply channel 10 inside the atomizing nozzle 6 at an angle β of 10° to 80°, preferably 40° to 60°, with respect to the burner axis A. In accordance with the invention, exit velocities of 10 m/s to 50 m/s, preferably of 10 m/s to 30 m/s, into the mixing chamber 8 are achieved thereby.
The mixing chamber 8 serves to accomplish an intensive mixing between the liquid fuel and the moderator and thereby divide the fuel into droplets. Via an outlet duct 11 , the mixing chamber 8 leads to the outlet opening 3 of the burner 1 , wherein the outlet duct 11 preferably tapers towards the outlet opening 3 . This taper is effected by choosing the two angles γ and δ, wherein the angle γ is equal to or greater than the angle δ. γ represents the angle of the outer fuel duct wall with respect to the burner axis and lies in the range from 0 to 20°, preferably from 0 to 10°. The angle δ between the inner fuel duct wall and a line parallel to the burner axis likewise lies in the range from 0 to 20°, preferably from 0 to 10°. The axial length of the mixing chamber 8 and of the outlet duct 11 up to the outlet opening 3 altogether is 10 mm to 300 mm, preferably 20 mm to 200 mm. Due to the taper of the outlet duct 11 , the atomized fuel is deflected towards the central oxidant jet and in addition accelerated once again shortly before exiting into the combustion chamber. Due to the taper of the outlet duct 11 , the outer fuel duct wall necessarily is wetted, so that the same can be cooled intensively by the fuel. The outlet velocity of the moderator-fuel mixture is 30 m/s to 100 m/s and hence lies in a similar order of magnitude as the exit velocity of the oxidant jet. Usually, the burner 1 is surrounded by a cooling-water jacket, which is not shown, however, in the FIGURE for simplification.
The velocity profile of the reaction media formed by the inventive arrangement and procedure at the burner base plate 4 and in its direct surroundings has the advantage that the recirculation of hot cracking gas from the combustion chamber in the outer region of the burner only meets with the atomized fuel. Hence, only endothermal or largely thermal neutral reactions are possible, which prevent a direct release of heat in the direct surroundings of the burner base plate 4 . In addition, a coking layer is formed in the outer region of the outlet opening 3 , which represents an additional thermal insulation for the introduced thermal radiation.
To vary the velocity profile at the outlet opening 11 of the burner 1 or to expand the load range of the burner 1 , a certain amount of moderator can be admixed to the oxidant already outside the burner 1 .
The burner 1 of the present invention is designed for gasification pressures in the combustion chamber of 10 bar to 120 bar at temperatures in the combustion chamber of 1000° C. to 1600° C. on average.
The burner 1 of the present invention can be accommodated in a common housing alone or as an arrangement of several burners 1 , wherein the fuel is passed through the one or more burners 1 into the combustion chamber. As an alternative, a plurality of individual burners 1 in accordance with the present invention can be installed in the combustion chamber, wherein the fuel, the moderator and the oxidant then are suitably distributed over the individual burners 1 .
As an alternative embodiment, the process of the invention can also be operated with a gaseous or supercritical, carbonaceous fuel (e.g. methane). In the burner of the invention, the two-component atomizing nozzle 6 then can be omitted, since an atomization of the fuel no longer is necessary. For this case, the burner can be designed more simple, since the moderator and the fuel can be introduced into the burner already in the mixed condition. In this alternative embodiment, the exit velocity for the oxidant and the reducing agent towards the combustion space as well as the angles γ and δ remain unchanged.
Due to the invention it is possible to process liquid fuels, in particular heavy oils and heavy viscous residues from refining plants, to synthesis gas by partial oxidation. The fuel initially is divided into droplets and intensively mixed with the moderator, before this mixture gets in contact with the oxygen-containing oxidant. By this media guidance it is ensured that the burner components facing the combustion chamber are cooled well by said media. This cooling in particular also takes place in operating conditions in which a cooling medium is not available.
EXAMPLES
A burner 1 of the invention was designed for a nominal throughput of up to 500 kg/h of liquid feedstock and tested with the process of the invention in a pilot plant.
Example 1
As liquid fuel, EL Fuel Oil (extra-light fuel oil) with an operating temperature of 20° C. and a kinematic viscosity (under operating conditions) of about 6 mm 2 /s was used. The oxidant was technically pure oxygen with a temperature of 250° C. As moderator, steam with a temperature of 310° C. was used. In the combustion chamber, a pressure of 61 bar existed. As cracking gas temperature at the burning chamber outlet 1410° C. were determined. The velocities of the reaction media were determined as follows: Exit velocity of the oxidant 90 m/s, velocity of the moderator steam in the two-component atomizing nozzle 9 120 m/s, velocity of the fuel EL fuel oil in the two-component atomizing nozzle 9 20 m/s.
The composition of the cracking gas achieved in this example was found to be 3.9% CO 2 , 47.7% CO and 48.9% H 2 (in mole percent, dry).
Example 2
As liquid fuel, Intermediate Fuel Oil IFO 380 SA (generally a mixture of heavy oil and diesel oil) with an operating temperature of 90° C. and a kinematic viscosity (under operating conditions) of about 120 mm 2 /s was used. The oxidant was technically pure oxygen with a temperature of 245° C. As moderator, steam with a temperature of 290° C. was used. In the combustion chamber, a pressure of 51 bar existed. As cracking gas temperature at the burning chamber outlet 1410° C. were determined. The velocities of the reaction media were determined as follows: Exit velocity of the oxidant 80 m/s, velocity of the moderator steam in the two-component atomizing nozzle 9 90 m/s, velocity of the fuel Intermediate Fuel Oil in the two-component atomizing nozzle 9 14 m/s.
The composition of the cracking gas achieved in this example was found to be 3.5% CO 2 , 50.3% CO and 45.8% H 2 (in mole percent, dry).
LIST OF REFERENCE NUMERALS
1 burner
2 central supply channel
3 outlet opening
4 burner base plate
5 supply conduit for moderator
6 two-component atomizing nozzle
7 annular gap
8 mixing chamber
9 supply conduit for fuel
10 bore/conical duct
11 outlet duct
A burner axis
α angle between outlet opening expansion and burner axis
β angle between fuel jet and burner axis
γangle between outer outlet duct wall and burner axis
δangle between inner outlet duct wall and a line parallel to the burner axis
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This invention relates to the production of synthesis gas by partial oxidation of liquid or gaseous, carbonaceous fuel in the presence of an oxygen-containing oxidant, wherein the fuel, the oxidant and a moderator are separately supplied to a burner and wherein the fuel and the moderator are mixed in a mixing chamber of the burner, before they are brought in contact with the oxidant. To reduce the load of the burner in particular during operation with transient conditions, the oxidant is centrally introduced through an outlet opening of the burner into a combustion chamber and the mixture of fuel and moderator is introduced through the outlet opening into the combustion chamber concentrically around the oxidant.
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REFERENCE TO RELATED APPLICATIONS
[0001] This is a continuation-in-part application claiming priority from U.S. Pat. No. 8,490,803 which issued on Jul. 23, 3013 from application Ser. No. 13/134,369 filed on Jun. 6, 2011 which is incorporated by reference in its entirety.
TECHNICAL FIELD
[0002] The present invention relates to the field of baby bottles and in particular to baby bottles including separable compartments for storage of a dry powder(powdered formula) and a liquid (water) prior to use and means releasing, combining and for mixing same.
BACKGROUND OF THE INVENTION
[0003] Powdered baby formula is mixed with water to produce a liquid formula milk replacement for consumption by infants. The dry powdered formula may be stored for long periods of time without refrigeration. However, once the powdered formula is mixed with water, the liquid formula must either be used or refrigerated within a short period of time. Otherwise the liquid formula spoils.
[0004] Powdered baby formula and water are typically mixed by combining predetermined amounts of powdered formula and water in the bottle, attaching the nipple and lid, and shaking the baby bottle to thoroughly mix the powder with the water. This mixing process may be safely and accurately performed with the aid of suitable measuring devices and substantially sterile surroundings. In addition, the mixed liquid formula and bottle may be stored and refrigerated for later use.
[0005] However, where refrigeration is unavailable, it is necessary to perform the mixing process just before use. If proper measuring devices and substantially sterile surroundings are unavailable, the process becomes problematic because contamination, spillage and the production of incorrectly mixed formula can occur. When traveling, it is inconvenient to carry formula and water separately and to measure out and mix the ingredients every time formula is needed for a baby.
DESCRIPTION OF THE RELATED ART
[0006] U.S. Pat. No. 5,275,298 by Holley, Jr. teaches a multi-component bottle with a mixing valve including a ball valve body which is rotated to align two sets of apertures to release the powdered formula into the lower water compartment for mixing. Holley stores the powdered formula within the hollow ball portion of the ball valve. Holley requires the alignment of two pairs of apertures and uses a complex ball valve with a cam arrangement for opening and closing the valve, unlike the present invention which only requires alignment of an aperture of a rotatable disk and a fixed disk.
[0007] U.S. Pat. No. 5,794,802 by Caola teaches a multi-component bottle with a push rod under the nipple which is used to force open a valve member. Caola's valve doesn't involve the alignment of two apertures or the same type of sliding element for opening as is used in the present invention.
[0008] U.S. Pat. No. 6,045,254 by Inbar et al teaches a movable plug in a necked down portion of the bottle to separate the powder from the water. Turning a top portion of the bottle raises the plug and allows the powder to fall into the liquid
[0009] U.S. Pat. No. 5,419,445 by Kaesemeyer has a sealing member between upper and lower compartments which is dislodged by twisting a lid portion on the top of the bottle. The sealing member falls to the bottom of the container. A user can't easily see when the sealing member is dislodged.
SUMMARY OF THE INVENTION
[0010] The present invention provides a baby bottle including a nipple and separable compartments for holding powdered formula and water. By sliding or rotating a knob to a pre-selected mix position, apertures in the separable compartments are aligned thereby allowing mixture of the powdered formula from an upper compartment into a lower compartment containing the water. The bottle is shaken to thoroughly mix the formula and the water, after which, the bottle and formula mix are ready to use.
[0011] More particularly, with the present invention, there is provided a combination baby bottle and powdered formula and water storage device comprising a lid with a nipple, a two part mixing valve and a water compartment. The lid is a cylindrically shaped lid including a top wall, a first sidewall, and a nipple. The first sidewall contains first female threads. The top wall has a circular aperture formed therein sized to receive the nipple and the bottom surface of the top wall abuts a top surface of the outer marginal portion of the nipple. The first part of the two part valve is a cylindrically shaped stationary valve member includes a second sidewall with first male threads at a top edge.
[0012] The first male threads are capable of being threaded into the first female threads to connect the lid to the stationary valve member. The stationary valve member includes a first circular bottom wall having a first aperture formed therein. The first aperture is sized to fit within a one third circular sector of the first bottom wall and is located so as not to include the center point of the first bottom wall. The second sidewall extends below the first bottom wall and includes second female threads. The second sidewall has a slot formed therein, the slot is above and parallel to the second bottom wall and extends around one third of the circumference of the second sidewall. The second part of the two part valve is a cylindrically shaped movable valve member having a third sidewall and a second bottom wall. The third sidewall has a first circumferential groove formed within the outside surface thereof which is located near a top edge. The third sidewall has a second circumferential groove formed within the outside surface and is located near the bottom edge. The first and the second grooves each have an polymeric or elastomeric sealing means such as an O-ring, washer, or disc disposed therein. The movable valve member is capable of being inserted within the stationary valve member whereupon the first bottom wall abuts the second bottom wall and the O-rings form a leak-proof seal between the second sidewall and the third sidewall. The slot is therefore situated between the O-rings and is sealed from leaking. The third sidewall has a rectangular window formed therein and located between the first groove and the second groove. The window contains a vertical axle with a lever pivoting thereon. The back side of the window is sealed off with a box which is integral with the third sidewall. The lever is capable of being fully contained within the window and the box and is capable of being pivoted out through the slot to a position where a user can push the lever to spin the movable valve member within the stationary valve member. The second circular bottom wall has a second aperture which is sized to fit within a one third circular sector of the second bottom wall. The second aperture is the same size as the first aperture and is located so as not to include the center point of the second bottom wall. The first aperture and the second aperture are totally mis-aligned when the lever is at a first end of the slot, thus keeping the formula powder separate from the water. The first aperture and the second aperture are totally aligned when the lever is at a second end of the slot. The cylindrically shaped water compartment includes a bottom wall and a fourth sidewall with second male threads at a top edge which are capable of being threaded into the second female threads to connect the stationary valve member to the water compartment.
[0013] More particularly, the baby bottle mixing device for mixing a liquid and powder, comprises, essentially of and/or consists of a cylindrically shaped lid including a top wall, a first sidewall, a first sidewall containing a first set of threads. The top wall has a circular aperture formed therein sized to receive said nipple. A cylindrical stationary valve member including a second sidewall with a first set of threads at a top edge, said first set of threads cooperatively engaging a second set of threads connecting said lid to said stationary valve member, a first circular bottom wall having a first aperture formed therein, said first aperture being sized to fit within a one third circular sector of said first bottom wall, said first aperture disposed between a side edge and a center point of said first bottom wall, said second sidewall extending below said first bottom wall and including third set of threads, said second sidewall having a slot formed therein, said slot disposed above and parallel to said second bottom wall, said slot extending around one third of a circumference of said second sidewall. A cylindrical shaped movable valve member includes a third sidewall and a second bottom wall, said third sidewall having a first circumferential groove formed within an outside surface thereof and located near a top edge thereof, said third sidewall having a second circumferential groove formed within an outside surface thereof and located near a bottom edge thereof, said first and said second grooves each including sealing means disposed therein, said movable valve member insertable within said stationary valve member whereupon said first bottom wall abuts said second bottom wall and said sealing means forming a leak-proof seal between said second sidewall and said third sidewall, said slot being situated between said grooves. The third sidewall has a rectangular window formed therein and located between said first groove and said second groove, said window containing a vertical axle with a lever pivoting thereon and said box and capable of being pivoted out through said slot to a position where a user can push said lever to spin said movable valve member within said stationary valve member, said second circular bottom wall having a second aperture formed therein, said second aperture sized to fit within a one third circular sector of said second bottom wall, said second aperture is of the same size as said first aperture, said second aperture extending from a side edge and a center point of said second bottom wall. The first aperture and said second aperture being misaligned when said lever is at a first end of said slot in an open position and said first aperture and said second aperture being aligned when said lever is at a second end of said slot in a closed position.
[0014] It is an object of the present invention to provide a pair of apertures contained in a rotatable disk and a fixed disk alignable whereby visible movement and positioning of same is clearly visible upon movement of an adjustment means such as a tab or knob located on the outside of the container.
[0015] It is an object of this invention to provide a baby bottle and storage device which separately stores dry formula and water for subsequent mixing and feeding.
[0016] It is an object of this invention to provide a baby bottle and storage device which provides any easy to use formula and water mixing valve.
[0017] It is an object of the baby bottle mixing device to include sealing means selected from the group consisting of an o-ring, a circumferential band, an elastomeric strip and combinations thereof.
[0018] It is an object of this invention to provide a baby bottle and storage device which provides a convenient and easily recognizable indication as to whether the mixing valve is open or closed.
[0019] It is an object of this invention to provide a baby bottle and storage device which is easily disassembled for cleaning.
[0020] An alternate embodiment of the present invention comprises, consists essentially of and/or consists of a baby bottle mixing device having the baby bottle with the mixing device threadably connecting thereto with a cylindrically shaped lid threadably engaging threads on top of the mixing device removably holding an elastomeric nipple onto the mixing device, and showing an optional nipple cover comprising a plastic dome secured to the lid by friction fit. The mixing device includes a cylindrical stationary valve member cap having a threaded cylindrical top for engaging a lid and an o-ring disposed therebetween, a tab or lever for rotating the movable valve member having an aperture therein of a selected size and shape inserted within the cap with an o-ring therebetween, a base member including an aperture of selected size and shape formed in a flat plate or panel in rotational sealable communication with the movable valve member including an o-ring therebetween, and an o-ring for insertion between the bottom surface of the base member and the top edge of a bottle.
[0021] Other objects, features, and advantages of the invention will be apparent with the following detailed description taken in conjunction with the accompanying drawings showing a preferred embodiment of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] A better understanding of the present invention will be had upon reference to the following description in conjunction with the accompanying drawings in which like numerals refer to like parts throughout the views wherein:
[0023] FIG. 1 is a front perspective view of the baby bottle.
[0024] FIG. 2 is a perspective view of a lid with a nipple installed.
[0025] FIG. 3 is a perspective view of the movable portion of the mixing valve.
[0026] FIG. 4 is a perspective view of the stationary portion of the mixing valve.
[0027] FIG. 5 is a perspective view of the water compartment.
[0028] FIG. 6 is a top view of the stationary portion of the mixing valve.
[0029] FIG. 7 is a top view of the movable portion of the mixing valve.
[0030] FIG. 8 is a perspective view of the stationary portion of the mixing valve showing the opening lever extended and ready for use.
[0031] FIG. 9 is a close up view of the opening lever on the movable portion of the mixing valve shown in FIG. 3 .
[0032] FIG. 10 is a top view of movable valve member 14 inside stationary valve member 24 with the apertures 36 and 37 mis-aligned.
[0033] FIG. 11 is a top view of movable valve member 14 inside stationary valve member 24 with the apertures 36 and 37 almost completely aligned.
[0034] FIG. 12 is a perspective view of an alternate embodiment of the baby bottle mixing device showing the baby bottle with the mixing device threadably connecting thereto with a cylindrically shaped lid threadably engaging threads on top of the mixing device removably holding an elastomeric nipple onto the mixing device, and showing an optional nipple cover comprising a plastic dome secured to the lid by friction fit.
[0035] FIG. 13 is a perspective view of the mixing device of FIG. 12 which is threadably connected to a conventional baby bottle.
[0036] FIG. 14 is an exploded view of the mixing device of FIGS. 13 showing the cylindrical stationary valve member cap having a threaded cylindrical top for engaging a lid and an o-ring disposed therebetween, a tab or lever for rotating the movable valve member having an aperture therein of a selected size and shape inserted within the cap with an o-ring therebetween, a base member including an aperture of selected size and shape formed in a flat plate or panel in rotational sealable communication with the movable valve member including an o-ring therebetween, and an o-ring for insertion between the bottom surface of the base member and the top edge of a bottle.
[0037] FIG. 15 is a sectional view of the mixing device of FIG. 14 showing placement of the o-rings, and positioning of the lever and movable valve member therein.
[0038] FIG. 16 is a bottom perspective view of the mixing device showing the lever and movable valve member rotated with respect to the base member showing the opening formed by the offset apertures.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0039] FIG. 1 shows a baby bottle 8 including a lid 10 with a nipple 12 , a stationary mixing valve member 24 with a slot 26 and a mixing lever 15 , and a water compartment 35 . FIGS. 2-5 show the individual components. Lid 10 , stationary mixing valve member 24 and water compartment 35 are cylindrical in shape.
[0040] FIG. 3 shows the movable mixing valve member 14 which is inserted into the top opening 21 of stationary mixing valve member 24 in preparation for use. Movable valve member 14 has an outer diameter which is slightly less than the inner diameter of opening 21 of stationary valve member 24 and includes sealing means comprising circumferential bands or most preferably O-rings 16 and 20 trapped within circular grooves surrounding the outside of the sidewall of movable valve member 14 . O-rings 16 and 20 provide a seal as movable valve member 14 is pressed down into stationary valve member 24 . As shown in FIG. 9 , lever 15 pivots on axle 17 in the side wall of movable mixing valve member 14 . Leak proof storage housing or box 13 is an integral part of the sidewall of movable valve member 14 and contains lever 15 and axle 17 so that powder stored within movable valve member 14 or liquid which is released into movable valve member 14 will not escape through window 19 in the outer sidewall of movable valve member 14 . Lever 15 must be able to rotate out of the way into the storage position as shown in FIG. 9 while inserting movable valve member 14 into stationary valve member 24
[0041] When inserting movable valve member 14 into stationary valve member 24 , bottom wall 11 of movable mixing valve member 14 is pressed down and seated against the bottom wall 23 of stationary valve member 24 . Bottom wall 23 has a crescent shaped aperture 36 . FIG. 8 shows bottom wall 23 and crescent aperture 36 in phantom lines. Bottom wall 11 of movable valve member 14 has a crescent shaped aperture 37 . Once movable valve member 14 is placed inside stationary valve member 24 , lever 15 may be swung out to a usable position as shown in FIG. 1 .
[0042] Lower portion 25 of stationary valve member 24 extends below bottom wall 23 and contains internal female threads (not shown) which are threaded onto male threads 32 to connect stationary valve member 24 to water compartment member 35 .
[0043] Lid 10 includes female threads (not shown) which are threaded onto male threads 22 of stationary mixing valve member 24 , shown in FIG. 4 . Lid 10 also includes a top wall 9 containing an aperture through which is inserted a nipple 12 . The outer marginal edge of nipple 12 is compressed securely between top wall 9 of lid 10 and the upper edge of stationary valve member 24 to form a leak proof fit. Water compartment member 35 includes sidewall 34 , male threads 32 and a bottom wall (not shown). It is understood that when the baby bottle is fully assembled, the threads connecting lid 10 , stationary valve member 24 and water compartment 35 form a water tight seal so that baby bottle 8 does not leak during use.
[0044] To use the bottle, a user first puts lever 15 in the storage position as shown in FIG. 9 . Then the user puts inserts valve member 14 down into stationary valve member 24 so that bottom wall 11 of movable mixing valve member 14 is pressed down and seated against the bottom wall 23 of stationary valve member 24 . Once movable valve member 14 is placed inside stationary valve member 24 , lever 15 is swung out to a usable position as shown in FIG. 1 . (With lever 15 in this position, apertures 36 and 37 are totally mis-aligned so that the powdered formula is prevented from dropping into water compartment 35 .) Next the user puts a selected amount of water in water compartment 35 . Then the user threads stationary valve member 24 onto water compartment 35 tightly. Then a selected amount of powdered formula is put into the stationary valve member 24 . Finally, lid member 10 (including nipple 12 ) is threaded tightly onto male threads 22 of stationary valve member 24 .
[0045] In the travel or storage mode, as shown in FIG. 10 , movable valve member 14 is positioned within stationary valve member 24 such that the apertures 36 and 37 are totally mis-aligned. FIG. 11 shows lever 15 and movable valve member 14 have been moved almost all the way to a position where apertures 36 and 37 are aligned and there is just a small part 38 of aperture 37 which is still covered. When a user wants to mix the water and powdered formula, lever 15 is moved all the way to the left end of slot 26 . This causes apertures 36 and 37 to become aligned and the formula will fall into the water. However, it can be seen that even if the apertures are only partially aligned, mixing of the water and powdered formula will still occur. Now the baby bottle is shaken and is ready to use. It is understood that apertures of other shapes such as round, square, triangular can be used instead of crescent and the selected shape is a matter of choice. In one preferred embodiment, the apertures in the valve members are sized to fit within a one third circular sector, that is, a circular sector of 120°, or less so that the movable valve must not be moved an excessive amount to align the apertures. Further, slot 26 would only extend one third of the way around the stationary valve member 24 .
[0046] Another preferred embodiment of the present invention is shown in FIGS. 12-16 .
[0047] The baby bottle mixing device is threadably connecting to the top of a baby bottle with a cylindrically shaped lid threadably engaging threads on top of the mixing device removably holding an elastomeric nipple having a flat lid onto the mixing device between the underside surface of the lid and the top edge of the mixing cap.
[0048] The cylindrical stationary valve member cap is generally conical in shape and includes a threaded cylindrical top side wall and smooth top edge for engaging the bottom surface of the lid and threadably engaging the interior threads of the lid to form a liquid tight seal therebetween. An o-ring may be disposed therebetween however the lid and/or top of the mixing chamber may be composed of a soft flexible material such as silicon so that a liquid tight seal may be obtained without the o-ring, or have an o-ring integrally formed therein. A tab or lever for rotating the movable valve member having an aperture therein of a selected size and shape is inserted within a rectangular opening formed in the cap for limited sideways motion. The lever cooperatively engages the cylindrical stationary valve member which is attached to the interior of the cap via a friction fit or threadable arrangement to form a liquid seal therewith. As shown in FIG. 15 , an o-ring is used to provide a seal; however the lid and/or top of the mixing chamber may be composed of a soft flexible material such as silicon so that a liquid tight seal may be obtained without the o-ring, or have an o-ring integrally formed therein.
[0049] The top of a base member including an aperture of selected size and shape comprises a flat plate or panel which abuts the cylindrical stationary valve member in rotational sealable communication with the movable valve member. An o-ring is disposed thereinbetween to provide a fluid tight seal. The cylindrical stationary valve member are sealed with o-ring for insertion between the bottom surface of the base member and the top edge of a bottle. In lieu of the o-ring, all of or a portion of the base member and/or stationary valve member may be composed of a soft flexible material such as silicon and formed so that a liquid tight seal may be obtained without the o-ring, or have an o-ring integrally formed therein. As shown in FIG. 15 , the cylindrical stationary valve member is held in the interior portion of the cap which includes threads on the interior bottom sidewall for cooperatively engaging threads formed on the top portion of the base member to secure the cylindrical stationary valve member in between and form a liquid tight seal. The entire unit can then be threadably connected to the top of a bottle.
[0050] The foregoing detailed description is given primarily for clearness of understanding and no unnecessary limitations are to be understood therefrom, for modification will become obvious to those skilled in the art upon reading this disclosure and may be made upon departing from the spirit of the invention and scope of the appended claims. Accordingly, this invention is not intended to be limited by the specific exemplification presented herein above. Rather, what is intended to be covered is within the spirit and scope of the appended claims.
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A baby bottle including a nipple and separable compartments for holding powdered formula and water. By sliding or rotating a knob to a pre-selected mix position, apertures in the separable compartments are aligned thereby allowing mixture of the powdered formula from an upper compartment into a lower compartment containing the water. The bottle is shaken to thoroughly mix the formula and the water, after which, the bottle and formula mix are ready to use.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an improvement in the structure of a camera body suited for a single reflex camera.
2. Description of the Prior Art
Usually the body of a single reflex camera is made of castings of light metals, such as aluminum for reasons of strength and precision. However, in order to manufacture such camera bodies much time and labor are needed because many manufacturing processes have to be performed, accordingly camera bodies are necessarily very expensive. Quite recently, on the other hand, the concept of a lightweight single reflex camera has been greatly desired, whereby the camera body forming the heaviest part of the single reflex camera is formed of metal as mentioned above, and, as a result, the weight of the camera body plays the largest part in this problem of providing a lightweight camera. Quite recently, to overcome this problem, forming the camera body out of plastic has been considered, however, because the distance between the rail face for guiding the film and the mount face for mounting the photographic lens, namely the so-called flange back is already fixed, it is often impossible to make the part of plastic, which part affords the aperture for determining the size of the picture and the rail face for guiding the film so that it is thick enough to provide the necessary strength. Thus, various problems occur, such as insufficient strength of the above mentioned aperture and the rail face or insufficient precision of the above mentioned flange back due to deformation by means of the outside temperature.
The first purpose of the present invention is to eliminate the above mentioned shortcoming for enabling the camera body to be formed out of plastic.
The second purpose of the present invention is to simplify the process for manufacturing the camera body.
Further, other purposes will be disclosed from the explanation to be made below in accordance with an embodiment of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows in an exploded perspective an embodiment of the present invention and more particularly it illustrates the camera body in which the metal block has been inserted, and the front plate;
FIG. 2 is an exploded perspective view showing the camera body in which the metal block has been inserted, as illustrated in FIG. 1, and a shutter unit; and
FIG. 3 is a lengthwise sectional view of the front plate shown in FIG. 1 and equipped with all of the view finder optics and also illustrating the camera body and the metal block.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention will be explained in detail below in accordance with the accompanying drawings of an embodiment of the present invention. In FIG. 1, a camera body 1 made of formed plastics includes screw oles 1a and 1b for mounting a shutter unit and a metal block 2 presenting an aperture 2e and rail faces 2f (note FIG. 3) inserted in the camera body 1. Front plate 3 is equipped with a reflex mirror 7, made of a metallic material and presenting a seat 3m equipped with a mount (not shown in the drawing) for mounting a photographic lens. The camera body has a rear wall in which a main section of the metal block is inserted. The main section includes the aperture 2e and the rail faces 2f. Extending from the rear wall of the camera body toward the front plate 3 are a pair of side walls and a bottom wall which terminate in a front wall. The front wall has an opening into which the front plate 3 fits. The metal block 2 has a first bent section inserted into the bottom wall of the camera body and extending toward the front wall. At the front wall of the camera body the first bent section provides a first mounting part consisting of the parts 2c and 2d. Along the edges of the main section extending upwardly from the bottom wall are two second bent sections projecting toward the front wall. A second mounting part consisting of the parts 2a and 2b is located at the upper edge of the main section of the metal block. The front plate includes a third mounting part consisting of parts 3c and 3d and a fourth mounting part consisting of parts 3a and 3b. In this arrangement, the first mounting part having parts 2c and 2d and the second mounting part having parts 2a and 2b of the metal block align, respectively, with the third mounting part having parts 3c and 3d and the fourth mounting part having parts 3a and 3b for engagement with one another by means of from the influence such as deformation of the plastic parts of the camera body due to the variation of the outside temperature.
In FIG. 2, a focal plane shutter unit 4 is illustrated including an upper base plate 5 and a lower base plate 6, with engaging holes 5a, 5b in the upper plate, which align with the screw holes 1a and 1b for connecting the camera body and the shutter unit by means of screws, not shown, so that the focal plane shutter unit 4 is mounted on the camera body 1. The shutter unit 4 includes a shutter diaphragm 14.
FIG. 3 shows in lengthwise section the front plate 3 shown illustrated in FIG. 1 and equipped with all of the view finder optics, including a mount 6, a reflex mirror 7, a focus plate 8 presenting a Fresnel plane, a Fresnel lens 9, a pentagonal roof prism 10, eye pieces 11a and 11b, an eye piece holder 12 and a screw 13 for mounting the eye piece holder 12 on the front plate 3. Further, FIG. 3 displays the arrangement of the front plate 3 relative to the camera body 1 and the metal block 2.
Below the process for manufacturing such a camera as described above, will be explained. At first the metal block 2 is put in a form for forming the camera body and the melted plastic is injected into the form after the form has been closed. After having been cooled the camera body 1, in which the metal block 2 has been inserted is removed after the form has been opened. Then the camera body 1 is equipped with the shutter unit 4, which is fixed on the camera body 1 by means of screws. Next the front plate 3 on which the view finder optics have been mounted, is fixed on the camera body and the metal block 2 inserted in the camera body, by means of screws in such a manner that most of the process for the parts in need of precision is finished.
As mentioned above, in accordance with the present invention, the camera body 1 is formed of plastic while the aperture 2e and the rail faces 2f for guiding film are formed in the metal block to provide sufficient strength for the aperture and the rail face for guiding film, which strength can not be obtained with plastic and to prevent the deformation of these parts due to the variation of the outside temperature, whereby the metal block is inserted into the camera body in such a manner that the precision of the flange bag is secured by connecting the inserted metal block with the front plate. Further, by mounting the shutter, which is made as one unit, on the camera body, the influence of the possible deformation of the camera body on the precision of the shutter is made as small as possible while by mounting the view finder optics on the front plate, made of metal material in order to obtain the necessary precision, all of the influence of the possible deformation of the plastic camera body upon the part in need of precision can be avoided. Because it is made possible to form the camera body out of plastic the manufacturing process has been simplified in such a manner that not only the manufacturing cost is cut down but also a camera light in weight is produced, which is very profitable.
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A camera body is molded out of plastic, and a metal block is incorporated into the camera body as it is molded. The metal block has an aperture for determining the size of picture and a rail face for guiding the film. Mounted on the camera body, which is capable of being equipped with the film feeding mechanism, is a front plate unit presenting a mounting seat for the reflex mirror. The front plate is mounted directly on the metal block.
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CROSS-REFERENCE TO RELATED APPLICATION
This application is a continuation, of application Ser. No. 07/716,057, filed on Jun. 17, 1991, now abandoned.
BACKGROUND OF THE INVENTION
The present invention relates to a method for monitoring or measuring the uniformity of tows with mechanical sensing elements in the course of production on a tow line.
In the production of synthetic fibers it is necessary to confer the desired textile properties on the spun filaments in a number of aftertreatment steps. Examples of aftertreatment steps which are generally necessary are drawing, setting, crimping and, where appropriate, cutting the continuous filaments into staple fibers. These aftertreatment steps are in general carried out in industry on tow lines by first combining the filaments from a plurality of spinnerets to form a tow which is then deposited in cans and then combining a plurality of these tows and subjecting them together on a tow line to the abovementioned aftertreatment steps of drawing, setting, crimping, etc. The tows aftertreated at the same time in this manner contain a very large number, generally from several hundred thousand to several million, individual filaments.
Especially tows which are subsequently to be further processed as converter tows, stretch-breaking tows or filling fiber tows must be of uniform quality and comprise in particular a constant number of filaments. Any change in the thickness of a tow leads to nonuniformity and hence a quality defect in the end product.
For technical reasons, for example because the canned tows of freshly spun filaments are not infinitely long, imperfections due to the running out of supply cans and the then necessary recruitment of replacement tows are unavoidable. Similarly, spinning-out problems which can lead to the breakage of individual filaments and to clumping and blob formation produce hard places in the tow and reduce the quality thereof. It is therefore necessary to monitor the tows for irregularities in order that the proportion of end product which is of inferior quality due to the presence of an irregularity may be eliminated from the production process. The tows are usually monitored visually by the operating personnel. In specific areas it is also already possible to use automatic equipment which is supposed to minimize the effects of tow irregularities on the end product.
Apparatus for this purpose is known for example from German Auslegeschrift 2,144,104, German Offenlegungsschrift 2,400,293 and German Patent No. 11,208. The apparatus known from German Auslegeschrift 2,144,104, and German Offenlegungsschrift 2,400,293 comprises sensing rollers which sense the thickness of the tow. In the apparatus of German Patent 11,208 this function is performed by a so-called sensing saddle, which is intended to be thrown upward by thick places in the tow.
German Offenlegungsschrift 3,306,687 describes an apparatus for bringing together a plurality of synthetic fiber tows upstream of a crimping box by means of pivotable deflecting rolls, said apparatus comprising tow tension measuring and control units. The tow tension is measured here only to provide automatic control of the deflecting rolls, so that the bringing together of the tows can be optimized. The apparatus does not have the purpose of detecting the quality of the tows.
SUMMARY OF THE INVENTION
By contrast, the present invention has for its object to provide a method whereby the quality of a synthetic fiber tow can be monitored and, if desired, evaluated. It has been found, surprisingly, that this object is achieved by a continuous monitoring of the tension of the synthetic fiber tow.
The present invention accordingly provides a method for monitoring or measuring the uniformity of synthetic fiber tows with mechanical sensing elements in the course of production on a tow line, wherein the tension of the running tow is measured upstream of a roll arrangement transporting the tow at a defined speed and is utilized as a measure of the uniformity of the tow.
Roll arrangements which on tow lines transport the tow at a defined speed are designed in such a way that, as a result of friction at the roll surface, the tow runs over the rolls at virtually the circumferential speed of the rolls.
Single rolls are in general not sufficient to impart a defined transport speed to a tow, since the friction between the tow and the roll surface is not sufficient and therefore usually permits a certain amount of slippage.
Roll arrangements which are capable of conferring a defined speed on a tow therefore contain two or more --usually for example up to seven (in septets)--rolls which are arranged either for the tow to pass through them in succession with a very large wrap angle or as pairs of squeeze rolls.
Pairs of squeeze rolls consist of a fixed roll and a mobile roll which presses with a great deal of force against the fixed roll. The tow to be transported is drawn into the nip between the pair of squeeze rolls and is transported at the circumferential speed of the squeeze rolls. This produces upstream of the squeeze rolls a tow tension which results from the overall construction of the tow line and which under standard conditions will fluctuate randomly about a standard value. Roll arrangements which are capable of conferring a defined transport speed on a tow will hereinafter be referred to as transport roll arrangements. Transport roll arrangements are found in many tow handling machines as intake rolls, for example in dryers, crimping boxes, tow-breakers, cutting machines, etc.
BRIEF DESCRIPTION OF THE DRAWING
The single FIGURE of drawing schematically illustrates a running tow and determination of the tension in the tow portion between spaced apart rollers.
DETAILED DESCRIPTION OF THE INVENTION
Referring in more particularity to the drawing, a running tow (1) is driven by squeeze rolls (2) and (2a) in the direction indicated by arrow (3). The running tow is supported by supporting roll (4), and a dancer roll (5) is positioned between the squeeze rolls (2, 2a) and the supporting roll (4) in contact with the running tow. The dancer roll (5) is capable of moving up and down and acts as a sensor for measuring the tension in the running tow.
It has been found that the passage of tow irregularities through the nip of the rolls (2, 2a) results in sudden changes of the tension in the running tow (1). These changes are detected by the tension-sensor (5). Hence, the occurrence of such changes in tension is an indicator of tow irregularities, and the corresponding signal of the tension sensor (5) is used to effect removal of the faulty place of the tow.
Depending on the relation of the tension of the tow upstream and downstream of rolls (2, 2a) the change in tension occurring at the place of the sensor (5) may be positive or negative.
The tow tension is therefore preferably measured within a zone which is upstream of the intake rolls of a tow treatment machine, for example a tow-to-top converter or a stuffer box, and which is equipped with a tension measuring instrument of a design known per se. If a fault in the synthetic fiber tow in the form of a thicker or thinner piece of tow should pass into the intake rolls (transport roll arrangement) of the monitored machine, this fault will show up as a change in the tow tension upstream of the intake rolls, which will be readily measurable with tension measuring heads known per se. If the transport roll arrangement consists of a multiple set of rolls, a fault in the form of a thick place in the tow will lead to a tension increase and a thin place in the tow will lead to a tension decrease. If the transport roll arrangement consists of a pair of squeeze rolls, then a thick place in the tow on passing through the nip will lead to a tension increase, and a thin place in the tow to a tension decrease, provided the tow is also held under tension downstream of the pair of squeeze rolls. If the tow is no longer under tension downstream of the squeeze rolls, which is the case for example downstream of the intake rolls of a stuffer box (crimping box), the reverse will apply: a thick place in the tow will lead to a tension decrease and a thin place will provoke a tension increase. Even so-called "hard places", which are formed for example due to an accumulation of broken filaments which have coalesced to form a hot-like polymer blobs, will on passing through the squeeze type intake rolls of a monitored machine, for example a stuffer box, lead to a sharp tension increase in the tow upstream of the intake rolls if downstream of the squeeze rolls (as in a stuffer box) the tow is no longer under tension.
Depending on the length of the faulty area in the synthetic fiber tow, shorter or longer tension changes will result upstream of the intake rolls. The frequency and length of tension deviations thus constitute a reliable measure of the quality of the monitored synthetic fiber tow.
The measured results can be evaluated in various ways, according to what information is desired about the quality of the tow. If, for example, faulty areas in the tow are to be categorically eliminated prior to further processing, a positive or negative tension change can be utilized for example for immediately switching off the tow transport. If the faulty area is to be channelled out of the product stream at a suitable point, it can be marked for example with a sighting color when the change in tension occurs. However, the tension signal can also start for example a timer which, as a function of the tow speed, controls the channelling-out of the faulty product.
For example, an alarm signal triggered by the tension change can be utilized to switch on a light within the area of the tow treatment apparatus, for example a crimping machine, downstream of the pair of rolls to indicate to the operative that an unacceptable fault has formed in the tow. At the same time a signal can be triggered, for example within the area of the tow plaiter, and, after an appropriate time for the fault to pass through the setter, a signal can be triggered upstream of the cutting machine to make it possible to interrupt the canning process in due time and to eliminate the off-spec portions resulting from the tow nonuniformity. The signal triggered by the change in tension can also be utilized, as mentioned earlier, to mark the faulty area in the tow with a sighting color. The off-spec portions can then be removed by hand or automatically, for example upstream of the tow depositor or at the cutting machine.
To prevent the minute random tension changes in the tow from triggering the measures which are designed to deal with a fault, preferably only those positive and/or negative tension changes in the tow are evaluated which are beyond a predetermined positive and/or negative threshold level, i.e. outside a predetermined threshold window. The threshold is set so as to be above the random tension changes which occur during standard operation.
However, the method of the present invention is suitable not only for triggering certain alarm devices or fault measures in the event of problems occurring in the tow but also for counting or integrating the tension changes by frequency and/or length. The resulting value can be standardized in terms of unit running time or length of the tow and then represents a measure of the average tow quality within the measured interval.
If an analog signal is derived from the tension measuring instrument, every change in the thickness of the tow can be continuously monitored on a recorder. Here too it is possible to define a limit for the analog signal at which the above-described fault measures are triggered.
The measuring of the tow tension can take place continuously, i.e. without interruption, in which case the tension signal obtained can be used for the continuous monitoring of the tow quality. However, the measuring can also take place intermittently at short intervals. This embodiment is of advantage if, for example, a single evaluating and control means is provided for a plurality of measuring sites. The evaluating computer then acts in a quasi time sharing mode.
Advantageously, the evaluation of the signal sequence for determining the tow quality is effected by a computer which can output the results in real time and hence makes process control possible, if desired.
To carry out the method of the present invention, it is possible to use any known means for measuring the tension of fiber tows. Of particular suitability are those means which employ a dancer roll, i.e. a mobile roll arranged between two fixed rolls which rests with pressure on the tow. This dancer roll can be controlled in various ways, it being possible for example to form a relatively long loop of tow by means of the dancer roll, so that the tow wraps around the dancer roll to about 180°. The dancer roll is held in this position by spring force, so that any tension change in the tow leads to a change in the position of the dancer roll. The change in the position of the dancer roll is then converted in a conventional manner into an electrical analog or digital signal and further processed as described above. However, a dancer roll can also be operated for example in a manner such that it is kept by a constantly measured force in a position in which it deflects the moving tow only relatively slightly, for example by an angle between 20° and 45°. The force required for maintaining this position is constantly measured and converted in a conventional manner, for example with an electronic tensiometer, into an electrical signal which is evaluated as described above.
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A method monitors and measures the uniformity of tows with mechanical sensing elements in the course of production on a tow line. The tension of the running tow is measured upstream of a transport roll arrangement and is utilized as a measure of the uniformity of the tow. Irregularities in the tow result in tow tension determination outside a predetermined tension range, and when the determined tension measurement is outside that range the irregular tow portions are remove. Also, the frequency of tow tension determination outside a predetermined range may be used as an indication of tow quality and for removing substandard tows.
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BACKGROUND OF THE INVENTION
The present invention related to a clamp for securely retaining a flexible cord, string, rope, and the like in a fixed position with respect to the clamp. Although the present invention may be employed for various applications wherein a cord or string is to be releasably retained in a selected position, the present invention finds particular applicability for various outdoor sports including backpacking, mountaineering and the like, and is useful when used in conjunction with outerwear or any other application wherein drawstrings are employed. A particular problem which has faced those who used hooded parkas, backpacks, sleeping bags or other devices which incorporate, as part of their structure, a drawstring, is to have a single device which may readily be operated to securely bind a drawstring in a selected position; but, which may also be easily activated to release the drawstring.
A solution to this problem has been to provide a pair of cylinders each of which is enclosed on one end, with the cylinders telescoping together so that the closed ends are opposite one another. Each of the cylinders is also provided with a pair of facing holes and, as the cylinders telescope, the holes may be registered in alignment with one another. A biasing spring is positioned in the larger of the two cylinders so that, upon telescoping the cylinders together, the holes may align with one another allowing a cord to pass therethrough. Upon release, then, the cord becomes bound between the sidewalls of the telescoping pieces.
While the above-described solution to the problems of retaining a drawstring has proved functionally acceptable, it none the less has several associated problems. For example, in such a standard cord lamp, the mating cylindrical pieces may rotate with respect to one another about their common axis so that the holes in each are not in a position of common longitudinal alignment. When this happens, of course, the telescoping together of the pieces does not transversely align the holes so as to allow a cord to pass therethrough and it becomes necessary for the user to reposition the pieces rotationally with respect to one another before using the same. A second problem incumbent in such an assembly occurs when a cord positioned and clamped therein becomes severed internally of the mechanism. Since it is the cord which prevents the pieces from separating from one another, a break in the cord allows the compression spring to separate the pieces thereby "exploding" the clamp. As noted above, since these cord clamps are often used in outdoor activities, it is necessary for the user to either carry spare clamps with him during such activities or resort to more crude methods of securing the strings such as tying the drawstrings together.
The present invention is an improvement over such existing cord clamps in that it provides telescoping members which are keyed for registering their respective holes in transverse alignment while at the same time it provides structure which interlocks the members to prevent separation.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide a novel cord clamp that is self-contained and interlocked to prevent separation of its component members.
It is another object of the present invention to provide a cord clamp that is compact and light in weight yet which will securely retain a cord positioned therein in a releasably secured relation along a selected location of that cord.
Yet another object of the present invention is to provide a cord clamp utilizing close fitting, telescoping members having alignable transverse bores which are keyed for registration with one another.
Still another object of the present invention is to provide a sealed interlocked cord clamp which may be employed with a variety of cords and which utilizes a pair of telescoping members which are guided by smooth continuous guide surfaces at all times during their relative movement.
To accomplish these objects, the novel and improved cord clamp according to the present invention includes a pair of telescoping members which, in the preferred embodiment, comprise a cylindrical plunger which is sized for close fitting insertion in a cylindrical sleeve. A cap member seals one end of the open sleeve and a compression spring is provided to urge the plunger outwardly of the sleeve. The plunger and sleeve are interlocked by means of a pair of abutting shoulders, one of the shoulders being on each of the plunger and the sleeve so that the plunger and sleeve may not be separated from one another after assembly. The plunger and sleeve each have a pair of opposed holes which are longitudinally aligned with one another and which may be registered in transverse or radial alignment when the plunger is moved into the interior of the sleeve. A channel and rib assembly is provided on the facing sidewalls to key the sleeve and plunger against relative rotation so as to maintain the respective holes in the sleeve and in the plunger in longitudinal alignment with one another and to provide smooth guide surfaces for controlling the relative axial movement of the sleeve and plunger. After assembly, the cap is securely positioned on the open end of the sleeve thereby providing a compact, interlocked clamp assembly.
These and other objects, advantages and features of the present invention will become more readily appreciated and understood when taken together with the following detailed description in conjunction with the accompanying drawings, in which:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the cord clamp according to the preferred embodiment of the present invention;
FIG. 2 is an exploded view in perspective of the cord clamp according to the preferred embodiment of the present invention;
FIG. 3 is a cross-sectional view of the cord clamp according to the present invention, shown in an expanded position;
FIG. 4 is a cross-sectional view of the cord clamp according to the preferred embodiment of the present invention, as shown in its compressed state showing the cord clamp turned 90 degrees from the position shown in FIG. 3; and
FIG. 5 is a cross-sectional view of an alternate embodiment of the end cap and spring for use with the preferred embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention relates to a novel cord clamp which is adapted to bind one or more flexible cords or strings at some desired location yet which allows quick release of that cord when so desired. The cord clamp is particularly applicable in devices utilizing draw strings since the cord clamp according to the present invention avoids the need for tying the cord while, at the same time, releasably secures the string or cord.
As shown in FIG. 1, cord clamp 10 receives a cord 12 and binds it against movement. To accomplish this binding, cord clamp 10 has a main body or sleeve 14 which receives a piston or plunger 16 with sleeve 14 and plunger 16 being relatively movable with respect to one another in an axial direction. Cord clamp 10, as broadly shown in FIG. 2, is comprised of four parts, including a cap 18 and a compression spring 20 in addition to sleeve 14 and plunger 16 discussed above.
Referring to FIGS. 2-4, it should be appreciated that sleeve 14 matingly receives plunger 16 so that plunger 16 has an interior portion 22 which is mounted internally of the sleeve 14 and an exterior portion 24 which protrudes from end 26 of sleeve 14. In the preferred embodiment sleeve 14 is substantially cylindrical, and is hollow so that it may receive plunger 16. It should be appreciated, however, that other geometrical configurations may be employed without departing from the scope of this invention, but it has been found that utilizing cylindrical members leads to ease and more economy in manufacture. to define a continuous guide surface for plunger 16. Ribs 30 extend substantially the entire length of sleeve 14 and define a close-fitting guide surface for plunger 16 as noted. Preferably, a pair of diametrically opposed bores or holes 38 are formed in a mid-portion of sidewall 32 of sleeve 14 so that holes 38 are in facing relationship to one another. Holes 38 are circumferentially offset 90 degrees from ribs 30 so that each of ribs 30 is in spaced relation to both of holes 38. Sleeve 14 has an open end 40 opposite lip 28 and opening 29. Open end 40 includes a surrounding shoulder 42 and an upstanding rim 44 with rim 44 and shoulder 42 being formed out of sidewall 32 of sleeve 14. As shown in FIGS. 3 and 4, rim 44, which extends around the circumference of open end 40, is outwardly flared so as to enable frictional attachment to cap 18 in the manner described below.
Plunger 16 is adapted to be inserted telescopically through sleeve 14 and is sized for a close fitting engagement with sleeve 14. Preferably, plunger 16 is generally a hollow cylinder having an open end 46 and a closed end 48, although plunger 16 could readily be of solid construction. A shoulder 50 has approximately the same radial thickness as does lip 28, and a pair of channels 52 are formed in the shoulder 50 which are sized for receiving ribs 30 with channels 52 extending in an axial or longitudinal direction. It should be noted that the bottom surface 54 of channels 52 form a continuous extension of the outer surface of the sidewall of plunger 16 so as to define a guide surface in cooperation with ribs 30. Therefore, it should be appreciated that the depth of channels 52 are approximately the same as the thickness or height of ribs 30.
A pair of opposed holes or bores 56 are formed in the sidewall of plunger 16 near end 46 at diametrically opposed positions with respect to one another. It should be noted that if plunger 16 is of solid construction, bores 56 should be formed as a single transverse bore diametrically extending completely through plunger 16. Preferrably, bores 56 are circular and intersect shoulders 50 approximately across a diameter of each of bores 56. In addition, bores 56 are spaced from channels 52 in a degree corresponding to the spacing between ribs 30 and holes 38. In the preferred embodiment, bores 56 are circumferentially spaced 90 degrees from channels 52.
Plunger 16 and sleeve 14 are mounted together in close fitting, telescopic engagement so that they are axially movable with respect to one another. As plunger 16 is positioned in sleeve 14, channels 52 receive ribs 30 thereby both guiding plunger 16 in sleeve 14 and preventing relative rotation of sleeve 14 and plunger 16. Exterior portion 24 of plunger 16 is sized to extend through the end of sleeve 14 opposite open end 40. It should be appreciated that lip 28 defines a opening of reduced cross-section so that, as exterior portion 24 of plunger 16 is moved past lip 28, shoulder 50 abuts lip 28 in a plane normal to their common axis to prevent plunger 16 and sleeve 14 from separating from one another. Since ribs 30 and holes 38 are spaced apart a corresponding distance as are bores 56 and channels 52, bores 56 and holes 38 are aligned along lines parallel to the longitudinal axis of sleeve 14 and plunger 16. It should also be appreciated that a single rib 30 and channel 52 construction may be used since the single construction would still prevent relative rotation of sleeve 14 and plunger 16.
A coil spring 20 which has a diameter which is the same as the diameter of plunger 50 is then positioned in sleeve 14 and a cap 18 is then placed in sealing relationship to sleeve 14 so that it encloses opening 40 thereby retaining spring 20 between cap 18 and plunger 16 as is shown in FIGS. 3 and 4. As noted above, holes 38 and bores 56 are axially aligned, but, when shoulder 50 is in abutting relationship with lip 28, holes 38 and bores 56 are not in transverse or radial alignment. Spring 20 normally biases sleeve 14 and plunger 16 into this position wherein the bores and holes are not registered with one another, which state is shown in FIG. 3, but, as plunger 16 is moved toward the interior of sleeve 14 against the force of compression spring 20, holes 38 and bores 56 may be registered with one another in transverse alignment.
In operation, then, plunger 16 and sleeve 14 are telescoped together so as to register holes 38 and bores 56 in transverse or radial alignment. A cord 12 may then be passed transversely through the assembled cord clamp 10. Upon release of plunger 16, compression spring 20 urges plunger 16 and sleeve 14 apart so that cord 12 becomes clamped by the sidewalls of sleeve 14 and plunger 16 as shown in FIG. 4. Since spring 20 maintains expansive pressure on plunger 16, cord 12 becomes securely retained by clamp 10 between the sidewalls of a respective hole 38 and bore 56.
Since spring 20 is under compression between plunger 16 and cap 18, it is desirable that cap 18 be securely mounted to sleeve 14. In the preferred embodiment, cap 18 is provided with a groove or channel 58 formed on the inner surface 60 of cap 18. In the preferred embodiment, channel 58 is formed by sidewall 62 of cap 18 and an upstanding circular ridge 64. Preferably, the free end of sidewall 62 is slightly enlarged to a thickness corresponding to the width of shoulder 42. Cap 18 is then frictionally secured to sleeve 14 with channel 58 receiving rim 44 in a frictionally locked relation. As noted, rim 44 is outwardly divergent so that it will frictionally lock with sidewall 62 thereby securely mounting cap 18 and sleeve 14 to one another.
In the preferred embodiment, cap 18, sleeve 14 and plunger 16 are formed out of a plastic material, and cap 18 and sleeve 14 are ultrasonically welded to one another after assembly. While it should be appreciated that cap 18, sleeve 14 and plunger 16 may be formed of any suitable material, it is preferable to form the apparatus out of a tough engineering thermoplastic, such as ABS. If another material is so selected, it is desirable to seal sleeve 14 and cap 18 in any manner of affixation such as by epoxy or welding. Since spring 20 may exert substantial force on cap 18, it should then be appreciated that this welding or sealing will prevent cap 18 from inadvertent detachment from sleeve 14.
It should also be noted with respect to sleeve 14, plunger 16, ribs 30 and channels 52 that the cord clamp may be constructed with the positions of ribs 30 and channels 52 reversed, although this is not shown in the Figures. In other words, it would be possible within the scope of this invention, to form a pair of channels longitudinally through lip 28 and to form a pair of ribs on the external sidewall of plunger 16 and to eliminate ribs 30 and channels 52 in the preferred embodiment. Since this new set of channels and ribs, then, would be the functional equivalent of ribs 30 and channels 52 in preventing relative rotation of sleeve 14 and plunger 16, this construction is not shown in the drawings; however, it is believed that this alteration would be a simple matter to one skilled in the art after reading the disclosure of the present application.
FIG. 5 discloses an alternate embodiment of end cap 18. While including all of the features described above cap 70 shown in FIG. 5 includes a raised portion 72 centrally located thereon. Raised portion 72 has a cross-section corresponding to the inner diameter of spring 20 so that spring 20 may be frictionally mounted thereon. Cap 70 facilitates assembly of the cord clamp 10 since spring 20 may be mounted on raised portion 72 prior to assembly.
Although the present invention has been described with particularity relative to the foregoing detailed description of the preferred embodiment, various modifications, changes, additions and applications other than those specifically mentioned herein will be readily apparent to those having normal skill in the art without departing from the spirit and scope of this invention.
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A cord clamp for binding flexible cords and the like having a sleeve and plunger which are axially movable with respect to one another. One end of each of the plunger and sleeve is provided with a shoulder to prevent separation as the pieces undergo axial movement, and a channel and rib are provided to prevent relative rotation of the plunger and sleeve. The plunger and sleeve are each provided with alignable openings in offset relation to the rib and channel assembly, and these openings move into and out of radial alignment as the plunger and sleeve are axially moved with respect to one another. A spring is provided to urge separation of the plunger and sleeve so that the openings are biased to be out of radial alignment. A cap member seals the entire structure at an end opposite the shoulder formed on the sleeve.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention discloses a method and apparatus for the transport of a homogeneous mixture of (chopped) fibers from a fiber generation source, such as a chopper gun, through a long flexible conduit to a workpiece. The transport apparatus is designed to eliminate nonhomogeneous flow of the fibers even as the conduit is maneuvered, so as to allow even deposition of the fibers on the workpiece.
2. Description of the Prior Art
Various manufacturers of nonwoven fabrics for use in glassfiber/resin composites have developed various apparatus for formation of these nonwoven fabrics or fiber "preforms". Reference for example Great Britain patent specification 659,088 of West Point Manufacturing Company, which teaches the removal of fibers from a fiber source by an air current, the passage of the fibers through a fixed transfer duct to a foraminous fiber-receiving member to form thereon a web of closely matted fibers, and the removal of the web from the member. The apparatus is designed to produce a two-dimensional fabric of constant thickness and width.
Reference also Great Britain Pat. No. 791,976 to Owens Corning Fiberglass Corporation wherein a fixed duct system supplies chopped fibers for their eventual deposition upon a preformed screen.
U.S. Pat. No. 3,833,698 discloses a movable chopper gun and roving cutter positioned within a rotatable preform, so as to allow even or uneven fiber deposition about the surface of the preform.
Reference also U.S. Pat. No. 4,117,067 issued Sept. 26, 1978 to Kenneth F. Charter et al; assignee, Owens Corning Fiberglass Corporation, entitled "High Production Method of Producing Glass Fiber Resin Composites and Articles Produced Thereby". Such an apparatus described in this '067 patent includes a device wherein air flow is introduced as a curtain along the sidewall of an inlet plenum, so as to assist the transport of fibers vertically downward through a fixed transport tube to their collection position. Such an apparatus incorporates a fiber chopper device at its inlet thereof.
Manufacturers of fiber reinforced plastic articles of manufacture continually attempt to improve the directed fiber placement process, wherein a chopper gun is used to generate chopped fibers, the fibers thereafter being deposited upon a workpiece. Boating manufacturers have typically used chopper gun technology during the manual layup or fabrication of boat hulls. Due to the lack of repeatability when the chopper gun is held manually, these manufacturers have attempted to automate the process by use of robotic equipment.
For example, a report entitled "Equipment Development and Feasibility Study of an Automated Preform Manufacturing System" was presented on Nov. 20, 1989 by D. M. Perelli of General Motors Corporation Advanced Engineering Staff, in which were described three different robotic/chopper gun systems, (hereinafter System 1, System 2, and System 3), which were operated to determine the feasibility of a robotic chopper gun system.
Referring now to FIG. 1, the apparatus shown as System 1 was used to produce door panel preforms. These preforms were of acceptable glass densities to meet the specifications for molding operations but the glass thickness was not uniform throughout the door panel preform.
The glass fibers deposited on the screen also exhibited a tendency to form ridges, the ridges being caused during various combinations of chopper fan shape, spray path followed by the robot, and various distances that the chopper gun held away from the preform screen. The System 1 stationary binder spray guns were ineffective in fully wetting out the glass.
Referring now to FIG. 2, the System 2, apparatus was used to produce both door panel and motor side compartment preforms. The System 2 apparatus was capable of spraying-up horizontally-mounted door panel preforms of exceptional uniformity as well as sufficient glass density. Glass fibers discharged from the flexible transport hose in a swirling pattern. This swirl-mixing within the hose made the glass discharge from the hose uniform in density. As a result, the fiber application to the horizontally-mounted door preform was uniform.
The vertical walls of the motor side compartment preform were difficult to spray uniformly, however, since the flexible transport hose had to be bent at the robot wrist to apply glass to the vertical walls of the screen. This bent portion of the hose apparently caused the glass fibers within the hose to stratify or lump together. Not surprisingly, the vertical walls of the finished preform showed signs of ridging. The System 2 assembly also did not offer a high degree of maneuverability due to the bulkiness of the flexible hose, which also made programming difficult, especially for continuous path programming. Movement of the robot wrist was also severely limited.
Referring now to FIG. 3, the System 3 apparatus was used to produce motor side compartment preforms which had correct and uniform glass fiber thickness. The preforms also exhibited the high degree of strength necessary for reaction injection molding, as well as the stiffness and strength needed for typical handling methods.
System 3 incorporates the best characteristics of Systems 1 and 2. Glass sprayed onto the three-dimensional screen was random and uniform across the preformed surface. No ridging was evident along the spray paths followed by the robot. Because the chopper gun could be pointed in any direction without bending the tube, no stratification of the glass fibers was evident in the discharge from the tube. Binder application was very good, and preform saturation was readily achieved. Overspray of glass on an average preform spray-up was less than 2%. This system was more mobile than System No. 2 though it was a bit less mobile than the System No. 1 design due to its added length.
Though System No. 3 performed the best this system as designed would burden the operator with large capital expense requirements, due to the large size of the robot required to lift and move the heavy chopper gun mounted at the end of the robot arm. The weight of the chopper gun held at the end of the robot arm requires an expensive robot having large lift capabilities.
An apparatus therefore need be developed, along with a method of operation, that allows the robotic application of chopped fibers to a workpiece of any orientation, wherein the lift capacity of the robot is minimized, and therefore its expense, by the remote location of the chopper gun away from the end of the arm of the robot. Such a system to be operative must avoid the fiber-clogging problems of System 2.
SUMMARY OF THE INVENTION
The present invention solves the fiber clogging problem by use of two transvector apparatus. One transvector apparatus is located at the inlet end of the hose and draws the fibers from the chopper gun discharge into the inlet end of the hose, and accelerates the fibers toward the outlet end of the hose. Use of this transvector, however, by itself did not solve the fiber clogging problem. A second transvector was tried solely at the discharge end of the hose but the fiber-clogging problem persisted.
The clogging problem was finally solved by use of a first transvector apparatus at the inlet to the hose, in combination with a second transvector apparatus at the discharge end of the hose. The first transvector apparently "pushes" the fibers through the hose, which in combination with the second transvector which "pulls" the fibers through the hose, causes the fibers to flow in a completely homogeneous manner through the tube, with no clogging, even when the tube is bent due to movement of the robot arm. The second transvector is carried by the end of the robot arm such that the arm does not need to support a heavy chopper gun.
The capital expense of the robot is therefore minimized due to the minimum lifting requirements imposed on the robot by the support of the non-cloggable light weight hose and second transvector apparatus.
The operating principles of transvector apparatus may be studied in U.S. Pat. No. 4,046,492 entitled "Air Flow Amplifier", issued Sept. 6, 1977 to L. R Inglis; assignee Vortec Corporation of Cincinnati, Ohio. Specific transvector information may be obtained from sales literature published by Vortec Corporation of 10125 Carver Road, Cincinnati, Ohio 45242.
It is therefore an object of the present invention to provide a fiber transport system from a remotely located chopper gun to a workpiece, by use of a long conduit or tube subject to bends, turns, and movement of the robot arm.
It is a feature of the invention for the fiber transport system to include a first transvector apparatus at the inlet end of a hose, as well as a second transvector apparatus at the outlet end of the hose.
These and other features, objects and advantages of the present invention will become apparent from the following detailed description, wherein references made to the Figures in the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a schematic representation in a side view of a robot held chopper gun applying chopped fiberglass to a flat preformed screen.
FIG. 2 is a schematic representation in a side view showing a remotely supported chopper gun supplying chopped fiberglass through a hose to a contoured preform screen.
FIG. 3 is a schematic representation in a side view showing a chopper gun supported at the end of a robot arm, delivering chopped fiberglass and binder to a contoured preform screen.
FIG. 4 shows a schematic representation in a side view in partial cross section of the chopped fiber transport apparatus.
FIG. 5A shows a schematic representation in a side view in cross section of the transvector apparatus located adjacent a chopper gun.
FIG. 5B shows a schematic representation in a side view in cross section of the transvector apparatus located adjacent a workpiece.
FIG. 6 presents in a graphical manner transvector performance curves.
FIG. 7 presents in a graphical manner transvector performance curves for a model 914/954 transvector.
DETAILED DESCRIPTION OF THE INVENTION
By way of introduction to the invention set forth in FIGS. 4 through 7, and to compare and contrast the present invention with the D. M. Perelli System 1, 2, and 3 apparatus mentioned earlier, it would be advantageous at this point to more fully describe and label each significant element of the Perelli apparatus of FIGS. 1, 2, and 3.
Referring now to FIG. 1, (System 1), a chopper gun 12 held by robot 14 is shown directing chopped fiberglass fibers 15 towards a flat preformed screen 16 held above an underfloor plenum 18, the gun 12 being supplied by roving 20 held in the top portion of booth 22. Binder 24 is sprayed by spray gun 26 toward the preform screen 16. As mentioned earlier, this system does not operate satisfactorily due to ridging of the fiberglass on the preform screen, as well as uneven deposition of the binder on the fibers 14.
Referring now to FIG. 2, (System 2), a robot 28 is shown holding a binder spray gun 30 which sprays binder 32 on contoured preform screen 34 held above underfloor plenum 36. Remotely mounted chopper gun 38 chops roving 40 and directs the chopped roving down through inductor 42, through hose 44 wherein the chopped fiberglass 46 blends with the binder 32 and is subsequently deposed on the preform screen 34.
The blower 47 provides the motive air whereby the glass fibers get entrained in the air within the inductor and the glass/air mixture is "pushed" through the hose. From time to time, if resistance is encountered to the flow, as when the hose is bent, the back pressure causes part of the air to blow backward through the chopper gun resulting in waste.
Plugging and flow interruptions of the chopped fiberglass 46, with the resultant formation of unacceptable preforms on screen 34, is caused by kinking or bending of the hose 44. System 2 advantageously does not have the relatively heavy chopper gun 38 mounted on the end of the robot arm 48, which permits the use of a smaller capacity robot 28.
Referring now to FIG. 3, (System 3), robot 50 is shown holding chopper gun 52. The chopper gun supplies chopped fiberglass and binder 54 through the tube 58 and inductor 56, and binder is sprayed from the binder spray gun 60. The chopped fiberglass and binder is directed to the contoured preform screen 62, held above the underfloor plenum 64 of booth 66, the roving 68 being supported by the booth. As mentioned earlier, the robot 50 must support the chopper gun 52 from the robot arm 70, and whereas the resulting preform 72 is acceptable, the capital expense associated with the increased size of robot 50 due to the suspended weight of the chopper gun 52 must be considered as a factor detrimental to the use of such a system.
Referring now to FIG. 4, the chopped fiber transport apparatus 80 of the present invention is shown, the apparatus 80 being useful for the transport of a homogeneous mixture of chopped fibers 82 from a chopped fiber generation means 84 to a workpiece 86. The chopped fiber generation means 84 in a preferred embodiment would include creels 88 supplying threads 90 to chopper gun 92, as is well known to the art.
The chopped fiber transport apparatus 80 in a preferred embodiment can be seen to include first flow amplification means 100 comprising a model 914/954 transvector supplied by the Vortec Corporation of 10125 Carver Road, Cincinnati, Ohio, 45242, and labelled as TV1 102, being shown in more detail in FIG. 5A.
Referring now to FIG. 5A the transvector apparatus TV1 102 can be seen to have an inlet opening 106 and an outlet 108 placed in fluid communication with the inlet opening 106, the inlet opening receiving the chopped fibers 82 from the chopped fiber generation means 84, the outlet opening 108 discharging the chopped fibers in an accelerated manner therethrough, as explained in further detail later in the specification. It should be noted that an air blower is not required at the inlet of the inlet opening 106 due to the effectiveness of the transvector TV1 102.
Returning again to FIG. 4, the transport apparatus can also be seen to include conduit means 110 such as in a preferred embodiment fixed hose 112 coupled in a continuous manner with flexible hose 114, though it is well recognized that many other hose or ducting combinations may be used to accomplish the same mechanical result. Conduit means 110 can be seen to have an inlet 116 along with an inlet opening 118 (shown in partial cutaway) as is well known to the art. Conduit means 110 can be seen to include a typical flow opening 111 defined about its entire length therein, (shown in partial cutaway).
Conduit means 110 can also be seen to have an outlet 120 and associated outlet opening 122 (shown in partial cutaway) as is well known to the art, the outlet opening 122 being in fluid communication with the inlet opening, the inlet opening receiving the chopped fibers 82 from the outlet opening 108 of the first flow amplification means, the outlet opening 108 discharging the chopped fibers therethrough.
Transport apparatus 80 can also be seen to include in a preferred embodiment second flow amplification means 124 such as a transvector similar or identical to the transvector TV1 102, the transvector for the second flow amplification means being labelled TV2 126, and being shown in FIG. 5B. Such second flow amplification means 124 would again have an inlet opening 106A and outlet opening 108A, the outlet opening 108A placed in fluid communication with the inlet opening 106A, the inlet opening 106A receiving chopped fibers 82 from the outlet opening 122 of the conduit means 110 (FIG. 4), the outlet opening 108A of the transvector 126 discharging the fibers 82 in accelerated homogeneous manner therefrom, preferably toward the workpiece.
Returning now to FIG. 4, support means 130 such as floor 132 may be used to support the chopper gun and the first flow amplification means 100.
The apparatus 80 can also be seen to include robotic movement means 136 such as a robot manufactured by Asea Brown Boveri Robotics Incorporated, New Berlin, Wis. In a preferred embodiment the robot 138 being Tralfa model no. TR 5000, generically having arm A 140 and arm B 142 for support of the second flow amplification means 124, the robot 138 capable of moving the second amplification means 124 in at least a one-dimensional manner. The robotic movement means 136 can be seen to be supported by the support means 130, the chopped fiber generation means 84 not being supported by the robotic movement means so as to minimize the required support capacity of the robot 138. This decreases the required lift capacity and also the expense of the robot 138, thereby decreasing the capital requirements of the overall system.
Inlet collection means 144, such as hopper 146, in a preferred embodiment is positioned between the chopper gun and the transvector TV1 102, the hopper having a 50 square inch opening for receipt of the fibers, as well as an 8 square inch funnel 148 opening area leading into the transvector TV1 102 opening 106. Inlet collection means 144 therefore can be seen to have an opening 150 defined therethrough placed in common fluid communication with the chopped fiber generation means and the inlet opening 106 of the first amplification means 100, for the collection of the chopped fibers generated by the chopped fiber generation means, and subsequent funneling of the fibers into the first flow amplification means.
Compressed air supply means 152, such as an air compressor 154 well known to the art, is provided for the supply of compressed air to compressed air openings 156, 156A in the side of the transvector apparatus TV1 102 and TV2 126 respectively.
Referring now to FIGS. 5A and 5B it should be understood that a transvector may be used either ducted, (having a hose connected to the discharge end such as TV1 102), or unducted, (discharging freely to the atmosphere with no hose connected to the discharge end such as TV2 126).
In general air from the compressed air opening 156 enters the small inlet and flows into the plenum chamber 170 surrounding the annular orifice 172. This orifice is only 0.002 inches wide and it represents a restriction to the compressed air. The air is throttled to atmospheric pressure as it passes through the orifice and it attains sonic velocity (1,000 feet per second).
This thin sheet of high velocity air shown by arrow 174 leaving the nozzle is deflected toward the outlet opening 108 by a small lip on the inlet ring, and it moves along the interior surfaces of the transvector and through its throat 176. Particles of fast moving air bump into still particles in the inlet region. This causes the relatively still particles to speed up and the fast particles to slow down. Thus, the primary stream is sacrificing velocity to induce larger amounts of air into the stream from the surroundings. A small suction is created in the nozzle outlet region 108, and an amplified flow moves through the throat 176.
The basic amplification ratio of a transvector is a measure of air amplification in a ducted installation, such as for TV1 102, whereas TV2 126 operates in an unducted manner, not having any conduit affixed to the outlet opening 108A thereof.
A basic amplification ratio of 20:1 in other words is determined by noting that the primary stream of compressed air supplied to compressed 30 air opening 156 will induce (by light suction) 19 times as much air from the surroundings to flow through the device as the amount of compressed air used. The total flow through the transvector TV 102 will be 19 plus 1 or 20 times as much as the compressed air usage.
The Vortec model 914/954 transvector used in the present embodiment has a nominal basic amplification ration of 20:1 though it should be recognized that the volume of compressed air supplied to the first flow amplification means may comprise from about 1/15th to about 1/40th the total air flow through the inlet opening 106 of the first flow amplification means.
An entrainment ratio may be given for the TV2 126 unducted application. This ratio is generally three times greater than the basic amplification ratio because it takes into account the additional entrainment of air surrounding the output stream of an unducted discharge, and is labelled in FIG. 5B by entrained air arrows 160, 160A. The effect of entrainment normally occurs a few feet from the transvector's outlet.
The performance chart shown in FIG. 6, which uses the basic amplification ratio, shows the total ducted output capacities of the four sizes of transvectors commercially available from the Vortec Corporation. The total flow is the sum of the induced flow (labelled by arrows 166, 166A in FIG. 5A), and the compressed air flow, the two components of the basic amplification ratio. It should be noted for optimum performance, that the resistance of the inlet or outlet ducting should be kept below 2 inches Water Column. Outlet flows decrease at higher resistances.
To determine the compressed air consumption for any model at any pressure, simply divide the total output flow shown in FIG. 6 by the basic amplification ratio. For example, a model 913 delivering 370 cubic feet per minute total output consumes about 19.5 standard cubic foot per minute of compressed air. This is found by dividing 370 by the basic amplification ratio of 19.
Referring now to FIG. 7 the dead end suction and dead end pressure respectively for the 914/954 transvector may be seen plotted versus inches of water column.
Other principles of operation of the transvector may be explored with personnel of the Vortec Corporation which may be reached by telephone at area code 800-441-7475, or by writing to their address given earlier.
In operation, the first flow amplification means, conduit means, and second flow amplification means are all placed in common fluid communication with one another, as shown in FIG. 4. The fixed hose length in the preferred embodiment from the first flow amplification means toward the robot was approximately 81/2 feet, using 41/2 inch EMT (OD) steel tubing. The flexible hose length from the end of the fixed hose to TV2 126, was 15 feet, using 4 inch flexible hose available commercially, a small reduction adapter being used between the fixed and flexible hoses.
Compressed air is supplied to the first and second flow amplification means 100, 124, the pressure of the supplied compressed air delivered to TV1 adjusted to be from about 2 to about 4 times the pressure of the compressed air supplied to the TV2 transvector. In a preferred embodiment the compressed air supply pressure to TV1 was established at 46 psi, whereas the compressed air supplied to TV2 was set at 15 psi by use of appropriate upstream regulators (not shown). The basic amplification ratio for the ducted TV1 transvector, (Vortec model 914/954) is 20:1, with a ducted output of 440 to 1,000 standard cubic foot per minute. The entrainment ratio for the unducted TV2 transvector is 60:1.
Once the compressed air flow is established through the transvectors, the chopper gun is started, and the chopped fibers flow from the gun sequentially through the first flow amplification means, conduit means, and second flow amplification means, the chopped fibers thereafter flowing in an accelerated homogeneous manner from the outlet of the second flow amplification means toward the workpiece 86. Inlet collection means 144 may be used to funnel the fibers into TV1.
In an illustrative embodiment of the invention PPG Industries thread, type number 5540, was used to feed the chopper gun. Each thread 90 (FIG. 4) flowed from its respective creel at 425 feet per minute or 0.67 pounds per minute, 4 strands of threads 90 being used simultaneously, yielding a total thread usage rate of 1700 feet per minute, or 2.68 pounds per minute of chopped fibers leaving the fiber generation means 84. The average length of the fibers 82 after exit from the chopper gun 92 was 1.5 inches.
The chopper gun 92 was manufactured by Finn and Fram Corporation and has a maximum motor speed of 850 rpm, wherein the speed control was set at 65%.
The workpiece 86 comprises a screen having an airflow such that a face air velocity of about 11 ft/sec is maintained through the screen holes even as the glass deposit is built up. The screen typically has 1/8" diameter holes spaced so as to give the screen an open area of about 80%.
The air velocity at point V 168, (FIG. 4) being located 2 inches from the center of discharge of TV2, was measured at approximately 4800 feet per minute. It should be noted that the exact velocity was difficult to measure; instantaneous readings varied from 4200 to 5500 feet per minute.
Once chopped fiber flow has been established through the transport apparatus 80 robot 138 may thereafter move arms 140, 142 so as to deposit the correct thickness, width, and depth of fibers 82 on various areas of workpiece 86. In the preferred embodiment the chopped fibers were deposited to a depth of from about 1/4" to about 3/8" on the workpiece.
It should be well understood that the above transport apparatus may be modified to transport fibers over greater lengths, such as by addition of further transvectors and additional lengths of hose. One possible system would include an additional transvector evenly spaced between TV1 and TV2 along with another 20' length of hose.
It should also be well understood that other flow amplification devices such as a Coanda airmover, venturi, or ejector apparatus may be used in place of, or in combination with the transvector apparatus, in order to achieve the same mechanical result of homogeneous fiber delivery from a chopper gun to a workpiece, depending on the desired flowrates and fiber characteristics that may be encountered. Interpretation of the phrase "flow amplification means" should not be limited to the transvector apparatus of Vortec Corporation. Additionally, although the above discussion relates to the use of air as a carrying medium for the fibers, it should be well understood that water may also be used to carry the fibers to a (submerged) workpiece, the flow amplification means being capable of amplifying the flow of water through a hose or conduit.
The control system used to operate the robot, with its inherent analog reference position monitoring/position feedback system, can also be utilized to continuously vary the pressure of the compressed air supplied to the transvectors, as well as the fiber quantity and fiber velocity of the fibers issuing from the chopper gun, so as to adjust the velocity and quantity of the fiber flow that issues from transvector TV2 as the transvector is moved relative to the workpiece.
Many other variations and modifications may be made in the apparatus and techniques herein before described, both by those having experience in this technology, without departing from the concept of the present invention. Accordingly, it should be clearly understood that the apparatus and methods depicted in the accompanying drawings and referred to in the foregoing description are illustrative only and are not intended as limitations on the scope of the invention.
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A method and apparatus are disclosed for the transport of a homogeneous mixture of chopped fibers, wherein the fibers remain in a homogeneously mixed condition during their transport from a chopper gun to a workpiece, by use of two transvector apparatus placed in series with a conduit attached therebetween.
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BACKGROUND OF THE INVENTION
1.Field of the Invention
The present invention relates to an epoxy resin composition which is excellent in heat-resistance and which can be used for insulation materials and laminate materials for electric and electronic parts, and particularly for sealing semiconductors.
2.Description of the Prior Art
The fields of electric equipment and electronic parts have the tendency to use high density mounting and multifunctionality. Accordingly, for insulation materials and laminate materials to be used in these fields, and particularly for sealing semiconductors, it is strongly desired to develop heat-resistant resin compositions capable of withstanding heat generation in the mounting step or in use. Technical innovation is particularly remarkable in the field of resin-sealing type semi-conductor equipment and the development of durable products for use in a more severe environment has been strongly required.
The above resin-sealing is generally conducted by transfer molding of epoxy resin compositions in view of economy. In particular a system of o-cresol novolak type epoxy resin which a novolak type phenol resin as a hardener is excellent in moisture resistance and hence is mainly employed today.
However, the resin-sealing type semiconductor equipment is being replaced by surface-mounted type semiconductor equipment according to the trend toward the above high density mounting. The surface-mounted type equipment is different from conventional inserted type semi-conductor equipment and the whole package is exposed to a soldering temperature of 200° C. or more. Additionally, in an environment of extended use at high temperatures such as in the periphery of automotive engines, the resin composition used for the sealing material is required to have a high heat-resistance for the severe environment. Conventional epoxy resin cannot fulfil such requirement.
SUMMARY OF THE INVENTION
The object of the present invention is to provide an epoxy resin composition having excellent heat-resistance, particularly an epoxy resin composition which can be applied to the resin-sealing type semiconductor equipment requiring high heat-resistance.
As a result of an intensive investigation in order to improve the heat-resistance of epoxy resins, the present inventors have found that excellent heat-resistance can be obtained by using a compound simultaneously comprising in the molecule a functional group capable of reacting with epoxy resin and a maleimide group having heat-resistance. Thus, the present invention has been completed.
One aspect of the present invention is a heat-resistant epoxy resin composition comprising an epoxy resin, an epoxy hardener, and 2-(4-hydroxyphenyl)-2-(4-maleimidophenyl)propane illustrated by formula (I) : ##STR1##
Another aspect of the present invention is a novel process for preparing the compound of formula (I) for use in the composition of the present invention.
The heat-resistant epoxy resin composition of the invention comprising 2-(4-hydroxyphenyl)-2-(4-maleimidophenyl)propane which has a maleimide group can provide high heat-resistance which could not be obtained with a conventional epoxy resin composition. When the resin composition is used for sealing the semiconductor equipment requiring high heat-resistance, excellent reliability can be obtained. Thus, the present invention is valuable in industry.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Conventional epoxy resins can be employed for the composition of the present invention as long as the epoxy resin is multivalent.
Exemplary epoxy resins which can be used include:
(1) novolak type epoxy resins such as glycidyl derivatives of phenol novolak and cresol novolak:
(2) glycidyl derivatives of other compounds having two or more active hydrogens in a molecule, for example, glycidy) type epoxy resins obtained by reacting polyhydric phenols such as bisphenol A, bis(hydroxyphenyl)methane, resorcinol, bis(hydroxyphenyl)ether, and tetrabromobisphenol A; polyhydric alcohols such as ethylene glycol, neopentyl glycol glycerol, trimethylolpropane, pentaerythritol, diethylene glycol, polypropylene glycol, bisphenol A-ethylene oxide adduct and trihydroxyethylisocyanurate; amino compounds such as ethylenediamine, aniline and bis(4-aminophenyl)-methane; and polycarboxylic acids such as adipic acid, phthalic acid and isophthalic acid; with epichlorohydrin or 2-methylepichlorohydrin, and:
(3) dicyclopentadiene diepoxide and butadiene dimer diepoxide.
One or more epoxy resins selected from the aliphatic and alicyclic epoxy resins such as above may be used.
A preferred epoxy resin is the novolak type epoxy resins such as glycidyl compounds of phenol novolak and cresol novolak in view of heat-resistance and electrical properties in particular.
Resins obtained by modifying the above epoxy resin with silicone oil or silicone rubber can also be used. Such resins include, for example, a silicone modified epoxy resin prepared by the process disclosed in Japanese Patent Laid-Open Publication SHO 62-270617(1987) and 62-273222(1987).
The epoxy hardener used in the composition of the present invention can be any type of epoxy hardener including phenol compounds, amine compounds, acid anhydrides and the like. Phenol compounds are preferred in view of moisture resistance and include, for example, novolak type phenol resins and aralkyl type phenol resins obtained by reacting phenols such as phenol, cresol and resorcinol with aldehydes or aralkyl ethers; and polyhydric phenols such as tri-hydroxyphenylalkanes and tetrahydroxyphenylalkanes. These phenol compounds are used singly or as a mixture.
The amount of the epoxy hardener used is in the range of 0.1 to 10 equivalents, preferably 0.5 to 2 equivalent per equivalents of the epoxy resin.
The composition of the present invention uses 2-(4-hydroxyphenyl)-2-(4-maleimidophenyl)propane, i.e., the compound of formula (I), as a required component.
The compound used can be prepared by known processes. However, a high purity compound can be prepared by a novel process found by the present inventors. The high purity compound can provide a composition which is excellent in heat-resistance and has good and stable quality.
The compound of formula (I) used for the composition of the invention, i.e., 2-(4-hydroxyphenyl)-2-(4-maleimidophenyl)propane is useful as a modifying agent for various polymers. The compound has conventionally been prepared, for example, by reacting 2-(4-hydroxyphenyl)-2-(4-aminophenyl)propane with maleic anhydride in the presence of a large amount of a dehydrating agent such as acetic anhydride, phosphorus oxide or condensed phosphoric acid as disclosed in Japanese Laid-Open Patent Publication SHO 55-149293(1980). However, the process produces acetylated compounds or esterified compounds as by-products because the amine compound used as the raw material has a hydroxyl group. Further, an addition reaction to the double bond of maleimide group takes place and leads to a decrease in the yield and purity and additionally to coloration. Consequently, 2-(4-hydroxyphenyl)-2-(4-maleimidophenyl)propane having good quality could not be obtained.
The novel process described below which has been found by the present inventors has eliminated the disadvantage of the above conventional process and can give a high purity 2-(4-hydroxyphenyl)-2-(4-maleimidophenyl)propane in high yield and without by-products.
That is, the embodiments of the preparation process in the present invention is to prepare the compound in high purity and high yield by conducting a dehydrating and ring-closing reaction of 2-(4-hydroxyphenyl)-2-(4-aminophenyl)propane with maleic anhydride in an organic solvent capable of forming a water azeotrope in the presence of an acid catalyst and an aprotic polar solvent.
The raw materials used in the process are 2-(4-hydroxyphenyl)-2-(4-aminophenyl)propane (hereinafter referred to as amine compound) and maleic anhydride. The amount of maleic anhydride is in the range of 1.0 to 1.5 moles, preferably 1.05 to 1.3 moles per mole of amine compound. When the amount of maleic anhydride is less than 1.0 mole, it sometimes causes formation of unfavorable by-products which are adducts of 2-(4-hydroxyphenyl)-2-(4-maleimidophenyl)propane and excess amine compound remains.
The reaction is carried out in the presence of a catalyst.
Exemplary catalysts which can be used include mineral acids such as sulfuric acid and phosphoric acid, heteropoly acids such as wolframic acid and phosphomolybdic acid, organic sulfonic acids such as p-toluenesulfonic acid and methanesulfonic acid, and halogenated carboxylic acids such as trichloroacetic acid and trifluoroacetic acid. Sulfuric acid and p-toluenesulfonic acid are preferred in particular.
The amount of the catalyst used is usually in the range of 0.5 to 5% by weight per total weight of amine compound and maleic anhydride. A catalyst amount less than 0.5% by weight leads to an insufficient effect of the catalyst. On the other hand, a catalyst amount exceeding 5% by weight is disadvantageous in economy and causes difficulty in removing the residual catalyst.
The reaction is carried out by using solvents. Exemplary solvents used are organic solvents which can remove water by azeotropic distillation. Preferred solvents include, for example, benzene, toluene, xylene, mesitylene and chlorobenzene. The solvent is used in an amount of 3 to 10 times by weight in order to smoothly progress the reaction.
In the process of the invention, an aprotic polar solvent is used in combination with the above organic solvent capable of forming water azeotrope. Exemplary aprotic polar solvents include N,N-dimethylacetamide, N,N-dimethylformamide, N-methyl-2 pyrrolidone, 1,3-dimethyl-2-imidazolidinone and N,N-diethylacetamide. The amount of the aprotic polar solvent is in the range of 10 to 40% by weight, preferably 20 to 30% by weight per weight of the above organic solvent.
The reaction is usually carried out by adding amine compound to the organic solvent solution of maleic anhydride and stirring at 150° C. or less, preferably 20° to 100° C. for 10 minutes or more, preferably 0.5 to 1 hour to form maleamic acid. Successively the aprotic polar solvent and the acid catalyst are added to the reaction mixture obtained, heated to 80° C. or more, preferably to a temperature range of 100° to 180° C., and stirred for 0.5 to 20 hours, preferably 4 to 8 hours to progress the reaction while azeotropically distilling off generated water. Alternatively, a mixture of maleic anhydride, the organic solvent and the catalyst is heated to a temperature range of 80° to 180° C. and a solution of amine compound in the aprotic polar solvent is added dropwise to the mixture. The reaction is progressed while azeotropically removing the generated water.
After completing the reaction by the above steps, the reaction mixture is cooled to 60° to 80° C., and is immediately concentrated under reduced pressure to distill off the solvent. Thereafter water or a mixture of water and a suitable solvent such as methanol, ethanol and isopropyl alcohol is added to obtain 2-(4-hydroxyphenyl)-2-(4-maleimidophenyl)propane.
2-(4-Hydroxyphenyl)-2-(4-maleimidophenyl)propane can be obtained by the process in high purity and high yield as compared with conventionally known processes.
The content of 2-(4-hydroxyphenyl)-2-(4-maleimidophenyl)propane in the composition of the invention is in the range of 10 to 400 parts by weight per 100 parts by weight of the epoxy resin. When the content is less than 10 parts by weight, good resistance to heat cannot be obtained. On the other hand, a content exceeding 400 parts by weight renders the cured product brittle.
Use of curing accelerators in the composition of the invention is desired in order to cure the resin. Curing accelerators which can be used include, for example, imidazoles such as 2-methylimidazole and 2-methyl-4-ethylimidazole; amines such as triethanolamine, triethylenediamine and N-methylmorpholine; organic phosphines such as tributylphosphine, triphenylphosphine and tritolylphosphine; tetraphenylborone salts such as tetraphenylphosphonium tetraphenylborate and triethylammonium tetraphenylborate; and 1,8-diazobicyclo (5,4,0)undecene-7 and derivatives thereof. These curing accelerators may be used singly or as a mixture and, when necessary, may also be used in combination with free-radical initiators such as organic peroxides or azo compounds.
The amount of these curing accelerators used are in the range of 0.01 to 10 parts by weight per 100 parts by weight of the sum of the epoxy hardener and the compound of formula (I).
Other amorphous or crystalline additives may be added to the resin composition in addition to the above components depending upon the use and objects. Representative additives include spherically fused silica powder, alumina powder, silicon nitride powder, silicon carbide powder, glass fibers and other inorganic fillers; release agents such as fatty acids, fatty acid salts and waxes; flame retardants such as bromine compounds, antimony compounds and phosphorus compounds; coloring agents such as carbon black and coupling agents such as silane base, titanate base, and zirco aluminate base.
The present invention will hereinafter be illustrated in detail by way of examples.
EXAMPLE 1
To a reaction vessel equipped with a stirrer, thermometer and an azeotropic distillation trap, 60 g (0.1 mole) of maleic anhydride, 480 g of toluene and 2.6 g of 95% sulfuric acid were charged and heated to a reflux temperature. A solution containing 114 g (0.5 mole) of 2-(4-hydroxyphenyl)-2-(4-aminophenyl)propane in 160 g of N,N'-dimethylacetamide was dropwise added from a dropping funnel over 4 to 5 hours and reacted for 5 hours at the same temperature. Generated water by the reaction was removed by azeotropic distillation. After completing the reaction, the reaction mixture was cooled to 80° to 90° C. and the solvent was successively removed under reduced pressure. The organic layer thus obtained was mixed with 100 ml of isopropyl alcohol and then 300 ml of water was added and stirred for 0.5 to 1 hour to precipitate crystals. The crystals were filtered and dried to obtain 147 g of 2-(4-hydroxyphenyl)-2-(4-maleimidophenyl)propane as yellow crystals. The yield was 96%.
The product had a melting point of 168°-171° C. and a purity of 99% by gel permeation chromatography (GPC).
______________________________________Elemental analysis (%) C H N______________________________________Calculated 74.8 5.5 4.6Found 74.1 5.66 4.5MS (EI): 307.sup.(M+1)______________________________________
EXAMPLE 2
The same procedures as conducted in Example 1 were carried out except that 480 g of chlorobenzene was used in place of toluene to obtain 149 g 2-(4-hydroxyphenyl)-2-(4-maleimidophenyl)propane as yellow crystals. The yield was 97%. The product had a melting point of 167° to 171° C. and a purity of 98.5% by GPC.
EXAMPLE 3
The same procedures as conducted in Example 1 were carried out except that 2.6 g of methanesulfonic acid was used as the catalyst, 160 g of N-methyl-2-pyrrolidone was used as the aprotic polar solvent, and 60 g (0.61 mole) of maleic anhydride was used. 2-(4-Hydroxyphenyl)-2-(4-maleimidophenyl)propane thus obtained was 147 g. The yield was 96%. The product was yellow crystals and had a melting point of 167°-171° C. and a purity of 98.5% by GPC.
EXAMPLE 4
To a reaction vessel equipped with a stirrer, thermometer and an azeotropic distillation trap, 300 g (0.3 mole) of maleic anhydride and 240 g of toluene were charged and 57 g (0.25 mole) of 2-(4-hydroxyphenyl)-2-(4-aminophenyl)propane was added with stirring. The reaction was carried out for an hour and then 1.3 g of p-toluenesulfonic acid and 80 g of N,N-dimethylacetamide were added. The resulting mixture was heated to reflux temperature and reacted for 10 hours while azeotropically distilling off water generated by the reaction. After completing the reaction, the reaction mixture was cooled to 80°-90° C. and the solvent was successively distilled off under reduced pressure. The residual organic layer was mixed with 100 ml of methanol and then 300 ml of water. The mixture was stirred for 0.5-1 hour to precipitate crystals. The crystals were filtered and dried to obtain 74 g of 2-(4-hydroxyphenyl)-2- 4-maleimidophenyl) propane as yellow crystals. The yield was 96.3%. The product had a melting point of 168°-171° C. and a purity of 99% GPC.
EXAMPLE 5
The same procedures as conducted in Example 4 was carried out except that 240 g of xylene was used as the organic solvent and 40 g of N,N-dimethylformamide was used as the aprotic polar solvent. 2-(4-Hydroxyphenyl)-2-(4-maleimidophenyl)propane thus obtained was 73.3 g. The yield was 95.5%.
The product was yellow crystals and had a melting point of 168°-171° C. and a purity of 99% by GPC.
EXAMPLES 6 AND 7, AND COMPARATIVE EXAMPLES 1
The formulations of Table 1, the raw material amounts of which are illustrated in parts by weight, were melt-kneaded on hot rolls at 100°-130° C. for 3 minutes, cooled, crushed and tabletted to obtain molding compositions.
The following raw materials were used in the formulations of Table 1.
______________________________________Epoxy resin Trademark, EOCN-1027 A product of Nippon Kayaku Co. Ltd.Novolak phenol resin Trademark, PN-80 A product of Nippon Kayaku Co., Ltd.Phenol aralkyl resin Trademark, MILEX XL-225L A product of Mitsui Toatsu Chemicals Inc.Fused silica Trademark, HARIMICK S-CO A product of Micron Co., Ltd.Silane coupling agent Trademark, NCU Silicone A-187 A product of Nippon Unicar Co., Ltd.______________________________________
These compositions were transfer molded at 180° C. for 3 minutes under a pressure of 30 kg/cm 2 to obtain test pieces for measuring physical properties.
Separately, a test element of 10×10 mm in dimension fitted on the four edges with aluminium bonding pad members of 100×100×1μ in dimension and aluminum wiring of 10μ in width which connected these pad members was mounted on the element fitting portion of a lead frame for a flat package. The lead frame and the bonding pad members were connected with gold wires and the above compositions were transfer molded under the same conditions as above. Thus, semiconductor equipment for tests were prepared. These molded specimens for the tests were post cured at 180° C. for 6 hours prior to the test. Results are illustrated in Table 2.
The following test methods were used.
Glass transition temperature: In accordance with TMA method
Flexural strength: In accordance with JIS K-6911
Heat deterioration test at 200° C.: Flexural strength was measured before and after storing the test piece in a constant temperature oven at 200° C. for 1000 hours. Results are illustrated by the retention of flexural strength.
VSP test: The semiconductor equipment for test was allowed to stand at 121° C. for 24 hours under pressure of 2 atmospheres in a pressure cooker tester and immediately immersed in a FLORENATE liquid (Trademark; FC-70, a product of Sumitomo 3M Co., Ltd.) which was previously maintained at 215° C. The numbers of pieces of semiconductor equipment which generated cracks in the packaging resin were counted. The numerator indicates the number of semiconductors which generated cracks. The denominator indicates the total number of semiconductors tested.
High temperature storage test: The semiconductor equipment was allowed to stand at 200° C. for 1000 hours in a constant temperature oven. Thereafter, operating tests was carried out. Results are illustrated by cumulative failure rate of the semiconductor equipment which did not operate in the test.
TABLE 1______________________________________ Example Example ComparativeRaw material 6 7 Example 1______________________________________Epoxy resin (EP = 195)*.sup.1 100 100 100Novolak phenol resin 46 23 54(OH = 106)*.sup.2Phenol aralkyl resin -- 38 --(OH = 174)Compound of Example 1 25 25 --Fused silica 606 659 546(average particle size 24μ)Triphenylphosphine 1.4 1.5 1.2Silane coupling agent 4.7 5.1 4.2Carnauba wax 3.5 3.8 3.2Carbon black 2.3 2.5 2.1Antimony oxide 7.8 8.5 7.0______________________________________ *.sup.1 Epoxy value *.sup.2 OH value
TABLE 2______________________________________ Example Example ComparativeProperty 6 7 Example 1______________________________________Glass transition temperature 180 180 160(°C.)Flexural strength (kg/cm.sup.2)room temperature 16.0 16.0 15.0215° C. 3.5 3.5 1.0Heat deterioration at 200° C. 80 80 50(Strength retention after1000 hrs: %)VSP test (Crack generation 0/20 0/20 20/20rate)High temperature storage 0 0 63test (Cumulative failurerate: %)______________________________________
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Heat-resistant epoxy resin composition obtained by incorporation of 2-(4-hydroxyphenyl)-2-(4-maleimidophenyl)propane in a resin composition consisting esssentially of epoxy resin and an epoxy hardener is disclosed.
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This is a divisional application based on the application bearing application Ser. No. 08/554,037 filed Nov. 6, 1995 now U.S. Pat. No. 5,630,803.
BACKGROUND
This invention relates to safety cap assemblies for needles, and in particular, safety cap assemblies for needles used in health-care related procedures.
Needles are, of course, employed in a wide variety of dental and medical procedures, including giving vaccines to patients, the injection of antibiotics, anesthetics, medicines, etc., the drawing of blood samples, intravenous feedings, and so on. Virtually all of these procedures subject medical personnel to the dangers of accidental sticking of the needle into a portion of their own bodies. The danger to the medical professional is primarily due to the possibility of accidentally injecting him or herself with an infectious pathogen derived from the patient after an injection has been delivered to the patient. At the present time, one need only mention the dread acronym "AIDS", (Acquired Immune Deficiency Syndrome) to understand the very real fears of the health professional.
Numerous devices have been suggested and employed to alleviate this problem. However, these devices and techniques require the knowledgeable, conscious cooperation of the physician, dentist, or nurse. Any distraction at the moment a used needle should be safety capped can result in a needle remaining uncapped, and hence a danger to anyone who might come in contact with it. This invention overcomes these disadvantages by providing a safety cap for needles that automatically safety caps the needle at the precise moment the needle is withdrawn from the patent.
The primary object of this invention is to provide a safety cap assembly for needles which automatically safety caps the needle at the moment the needle is withdrawn from the patient, thereby significantly reducing the posssibility of accidental injection.
A further object of the invention is to provide for automatic safety capping of used needles without the requirement of any operator attention.
An additional object of the invention is to provide for automatic safety capping of used needles without the requirement of any operator manipulation to accomplish this safety capping.
Still another object is to provide an automatic safety cap assembly for needles which is light in weight and inexpensive to manufacture.
An additional object of the invention, is to provide an automatic safety cap assembly that cannot inadvertently expose a used needle.
Another object of the invention is to provide an automatic safety cap assembly for virtually any length and gauge of needle.
SUMMARY
These and other objects are obtained in the instant invention of a safety needle cap for needles used in health-care related procedures.
Syringes, medicine delivery systems, etc. (hereinafter referred to as a "system") are supplied to the medical professional in a variety of ways. They may be made of glass or plastic, with attached, or to be attached needles usually being fabricated in metal, often stainless steel. A system may be supplied filled with appropriate medications, etc., or empty, depending upon the use to be employed. In any case, when a system combined with a needle is being used, the needle is connected to the base of the system by means of an enlarged structure (relative to the diameter of the needle itself) which is either a structural part of the needle, or the system to which the needle is affixed. This enlarged structure which connects the needle to the system, providing a conduit within this structure for fluid flow between the needle and the syringe, is commonly referred to as the needle "hub".
I have found that a safety cap means and an elastic sheath means combination can be fabricated so as to be put in place on virtually any needle assembly, including needle-hub assemblies and individual needles packaged in their own sterile environment. And, of course, the safety cap-elastic sheath assembly combination can be supplied already in place on systems with needles previously connected. The safety cap means of the invention consists essentially of a cap, which can be fabricated in metal or preferably economically molded in a suitable plastic such as, for example, polycarbonate, or any material, which is impenetrable for the particular gauge needle to be enclosed. The elastic sheath means attached to the safety cap means can be fabricated in a variety of resilient materials, such as for example, latex or natural rubber, plastic elastomers, or even plastic or metal springs. By the term "elastic", it is meant a material or structure which is capable of being stretched or compressed, and which, upon release of the stretching or compressing forces, returns substantially to its original shape.
In a first version of the invention to be described, one end of a latex rubber sleeve is attached over the needle hub, while at the other end of the sleeve, a safety needle cap is attached. The safety needle cap can be in a variety of shapes and sizes, a tubular shape being considered practical. This tubular shaped cap is completely open at one end and is connected to the elastic latex sleeve. The other end of the cap is closed except for an opening just large enough to accommodate passage of the particular gauge needle being used. The safety needle cap is attached to the sleeve so that the needle opening at the end of the cap is sufficiently misaligned from axial alignment with the needle, when the latex sleeve is not being compressed, so as to preclude accidental, re entry of the needle through the hole.
In this embodiment, to use the system, the operator would manually position the safety cap so that its opening is in axial alignment with the needle. He would then push the needle through the opening in the cap- the elastic, latex sleeve now being compressed and put under tension by this action of the operator. Depending on the inherent resilience of the elastomeric material employed, axially extending slits, if necessary, running partially along the length of the latex sheath, can facilitate this compression of the sheath. With the needle now exposed, the health professional can now proceed and insert the needle into the patient. The safety needle cap now is in contact with the patient, as for example, the arm of the patient, the cap simply riding back over the needle as the sheath is further contracted by the force applied by the health professional in inserting the needle to the required depth. After the injection, the operator simply withdraws the needle from the patient without the necessity of any thought being given to the safety needle cap. The instant the needle is free of the patient, the elastic tension in the compressed latex sheath is released, causing the safety cap to snap back to its original, off-axis or quiescent position. The needle tip is now safely contained within the needle cap where, of course, it cannot, inadvertently reenter the cap opening. The enclosed needle-hub combination can now be safely disposed of by a health professional, or technician, without any danger of accidentally causing the tip of the needle to protrude from the cap. The entire capping procedure is accomplished automatically, and without reference to the alertness or lack thereof of the operator.
Additional conveniences can be added to the above described device and procedure. For example, in a second version to be described, the safety needle cap-elastic sheath assembly can be supplied with a safety needle assembly enclosure having slots along its length to accommodate oppositely positioned projecting arms affixed to the safety needle cap. In this version, the cap and sheath means and needle would be supplied enclosed within this needle assembly enclosure. This is done with or without the assembly already in place on a system. The projecting arms on the safety needle cap would project through the slots within the safety needle assembly enclosure, the needle is in axial alignment with the needle opening within the cap, the tip of the needle now protruding through this needle opening. In this manner, the device is supplied in a ready-to-operate configuration. To use this version of the invention, the operator places his or her fingers on the projecting arms of the safety needle cap, removes the safety needle assembly enclosure, and proceeds as described in the first version of the invention with the injection. Again, after the needle is removed from the patient, the safety needle cap automatically snaps back to an off-axis position where the cap opening is out of axial alignment position with the needle, so that it is safely captured within the cap.
Two basic designs for the safety cap are disclosed. The first is relatively simple and includes a front face portion including an axially disposed, needle hole of sufficient size so as to accommodate the needle gauge employed. As described, the tubular cap includes cylindrical sidewall means that connects to the elastic sheath means. The sidewall means as assembled to the elastic sheath means extends backwards, in the direction of the needle hub, a sufficient distance so that the needle tip is captured within the volume defined by said front face portion and the distal end of the sidewall.
A second cap design includes a front face portion wherein the needle opening comprises a frusto-conically shaped opening, including a smaller opening on the interior surface of said front face portion and a larger opening on the exterior surface of said face portion. A second, rearwardly disposed face portion includes a second opening and a tubular extension extending rearwardly therefrom, the axis of the second opening and tubular extension being offset from the axis of the openings in the front face portion. This axis offset feature leverages the safety cap, in relation to the needle, so that when the elastic sheath means is in its released, quiescent disposition, the axis of the needle is offset from the axis of the opening in the front face portion of the cap.
The frusto-conical opening in the front face portion is adaptable to be able to retain gauze or similar material to capture and absorb body fluids as the needle, after use, is enveloped within the cap volume defined by the front face protion and sidewalls.
Additional safety enhancing features for use with the cap of either design are disclosed. These include a flap member, hingedly connected to the cap sidewall and disposed in relation to the needle to close off the opening in the front face portion after the device is released from the compressed, sheath means, position. Alternately, the area in the vicinity of the juncture of the sidewall and face portion can be packed with styrofoam or similar material which will capture the needle tip in the sheath means-released position.
In a third version of the invention to be described, the elastic sheath means can be in the form of a metal or plastic spring. The purpose of this spring type of elastic sheath means is the same as for the previous two versions, i.e., to maintain the safety cap in a position so that it will automatically snap back over the needle, with the needle opening within the cap out of alignment with the axial alignment of the needle, after the needle has been withdrawn from the patient. The spring can be enclosed in its own fabric sheath so as to facilitate its connection to the safety cap and needle hub.
A further embodiment depicts the safety cap configured in an "elbow" form. In this version the axial misalignment as is necessary between the cap and the needle in the relaxed, quiescent state is inherent in the cap design.
As will be more fully discussed, the structure of the safety needle cap assembly of the invention can have further modifications to virtually rule out any possibility of inadvertently repositioning the safety needle cap after use in a way that would permit the tip of the needle to re-emerge from the needle opening within the cap. Obviously, on all versions cited above, a sterile safety package, such as a safety foil, can be provided to enclose any described safety needle cap means and elastic sheath means assembly as supplied with or without needles and syringes.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an elevational, sectional view of one version of the safety needle cap assembly of the invention.
FIG. 2 is an elevational, partial sectional view of the version of the safety needle cap assembly of FIG. 1, illustrating the device ready for use.
FIG. 3 is an elevational view of the device shown in FIGS. 1 and 2, illustrating the position of the safety needle cap after use.
FIG. 4 is an elevational, partial sectional view of a version of the invention, showing a safety needle cap assembly enclosure and modified safety needle cap positioning the needle in ready for use, axial alignment with the needle opening within the cap.
FIG. 4A is a top plan view of the safety needle cap assembly enclosure and syringe depicted in FIG. 4.
FIG. 4B is a view of the cap assembly of FIG. 4A, taken along lines 4B--4B in that view.
FIG. 5 is an elevational view of the invention depicted in FIG. 4, illustrating the position of the safety needle cap after use.
FIG. 6 is an elevational, partial sectional view of a version of the invention which employs a spring for the elastic sheath means, and depicts a second embodiment of the safety needle cap means.
FIG. 6A is a top plan view of a part of the safety needle cap assembly enclosure and syringe depicted in FIG. 6.
FIG. 7 is an elevational view of the invention depicted in FIG. 6, showing the position of the safety needle cap after use.
FIG. 8 is a perspective view of one version of the invention as being used to deliver an injection to the arm of a patient.
FIG. 9 illustrates the version of the invention as depicted in FIG. 8 after the needle has been withdrawn from the patient's arm.
FIGS. 10, 11(a), 11(b), 12(a), 12(b) depict in elevational views a modification to the safety cap feature of the invention.
FIG. 13 depicts yet another modification of the safety cap feature of the invention; and, an adaptation of the elastic sheath means portion.
FIGS. 14(a) and 14(b) depict in front elevational and side, sectional elevational views the details of one embodiment of the safety cap feature of the invention.
FIG. 15 is a partial, elevational view depicting a further embodiment of the safety cap which is formed in an elbow configuration to accommodate the purposes of the invention.
DETAILED DESCRIPTION
As noted above, the present invention has broad application. For purposes of illustration only, the needle system to be described hereinafter will focus on the syringe system which includes a syringe barrel and plunger. The needle-hub in this system can be formed as part of the barrel or be separate therefrom and which, together with the needle, inserted typically into an opening in the syringe barrel.
Turning now to the drawings wherein similar structures, having identical functions, are denoted with the same numerals, FIG. 1 illustrates a complete first version 10 of the safety needle cap assembly of the invention. A syringe 12 is shown with an attached needle 22. The needle 22 is shown enclosed within an elastic sheath means 16, the elastic sheath means being connected at one end to the hub 20 of the needle, and at its other end to a safety needle cap 18. The elastic sheath means can be affixed to the needle hub and safety cap by any convenient means, such as with suitable adhesives, clips (not shown), etc. Where the elastic sheath is formed of an elastomeric material such as latex, the connection can be made by any suitable means including a frictional fit between the two pieces. The elastic sheath means 16 can be fabricated in a variety of suitable elastomers, e.g. latex rubbers, capable of being easily compressed under tension, and including a good "memory" so as to enable the elastic sheath means to return to its original shape when the tension is released. Other resilient means, for example, a spring, can be employed as the elastic sheath means as will be more fully described and illustrated in FIGS. 6, 6A and 7.
The safety needle cap 18 itself can be fabricated out of a number of hard materials, which will be impenetrable to the needle tip, for example, a clear plastic such as polycarbonate. The shape and size of the safety needle cap can vary depending on applications and design preferences, a tubular shape being suitable for some applications as depicted in FIG. 1. See also FIG. 15 and the attending description.
The tubular shaped safety needle cap is shown fully open 27 at one end for attachment to the elastic sheath 16. As is the case with the needle hub, the other end of the elastic sheath 29 can be attached to the safety needle cap by any convenient means, such as with a suitable adhesive, clips (not shown), frictional fit, etc. The other end of the safety needle cap is closed except for an interior opening 28 within the cap of just sufficient diameter as to permit the passage of the syringe needle 22 through this opening. As will be more fully illustrated and explained, this is an important feature of the invention. It virtually precludes the possibility of inadvertent, re-emergence of the tip 21 of the needle after the needle 22 has been used.
The exterior portion 26 of the interior cap opening 28 is an enlarged frusto-conical shape. It precludes body fluids on the needle from contacting the surface 31 of face portion 33. Gauze or other absorbent mesh work, (see FIGS. 14(a) and FIG. 14(b)), can be secured within the frusto-conically shaped opening to absorp any remaining body fluids on the exterior of the needle as the needle withdraws within the cap after use.
The safety needle cap 18 is affixed to the end of the elastic sheath means. The length of the sheath means between its points of attachment to the cap 18 and the hub 20 is such that the needle tip is enclosed in the volume defined by the face/portion of the cap 33 and the sidewall 35 when the sheath is in its released condition, i.e. not under compression forces. In this relaxed state, the needle opening 28 within the cap is offset from the axial alignment of the syringe 12 and attached syringe needle 22. This arrangement positions the tip 21 of the needle along the upper wall 32 of the tubular side wall of the cap. The elastic sheath means is shown as a tube of latex rubber having slits 24, if necessary, along a portion of the length of the elastic sheath so as to facilitate compressing the sheath when required. The slits can also facilitate a "drooping" of the cap end of the sheath when the system is in the released condition. Where elastomeric material is used, the requirement for slits will depend in part on the gauge, thickness, density, etc. of the material. The entire safety needle cap 18, elastic sheath 16 and syringe needle 22, are shown enclosed in a sterile enclosure 14, which is removed at an appropriate time before use.
FIG. 2 illustrates the version of the invention depicted in FIG. 1, now ready to be utilized with a patient. The sterile metal foil 14 has been removed, and the safety needle cap 18 has been manually moved (not shown) so that the needle opening 28 in the cap is in axial alignment with the hypodermic needle 22, the cap being moved longitudinally along the axis alignment with the needle, causing the elastic sheath 16 to be compressed 30 and therefore under tension, while at the same time exposing the tip 21 of the needle 22. With the hypodermic needle 22 in this position, the needle can now be inserted into the patient to perform the required medical procedure.
FIG. 3 illustrates the version of the invention depicted in FIGS. 1 and 2 after the needle has been withdrawn from the patient. This procedure is best understood from FIGS. 8 and 9. The moment the needle is withdrawn from the patient, the elastic tension within the elastic sheath 16 is released which causes the safety needle cap 18 to snap back into its original position. In returning to its original positions, the hypodermic needle is caused to be withdrawn to a position within the cap, with the tip 21 of the needle now harmlessly in contact with the inner surface of the upper wall 32 of the safety needle cap 18. The syringe 12 and needle 22 combination, including the safety needle cap 18 and elastic sheath 16, can now be disposed of safely. It is to be noted that the securing of the now potentially dangerous hypodermic needle within the safety needle cap of the invention is accomplished without any manual manipulations by the health professional, or even active consciousness of performing this often extremely important safety procedure.
FIG. 4 illustrates a second version of the invention in which a safety needle enclosure assembly 37 cooperates with a modified safety needle cap 39. The modified safety needle cap 39 includes arms 40 attached to and projecting radially outward from the side wall 46 of the modified cap. The attached arms 40 project through slots 42 in the safety needle enclosure assembly 37 (FIG. 4A). The axial length of the enclosure assembly 37 and length of slots 42 are such, that, when the assembly 37 and sheath-cap combination 16-39 is in place on the syringe-needle combination, with the one end of the sheath means secured to the needle hub 20, the arms 40 cooperate with the closed ends of slots 42 to maintain the elastic sheath in a contracted condition under elastic tension. The safety needle enclosure assembly 37 itself can be fabricated in a variety of plastic materials. The safety needle enclosure assembly 37 can have a smaller diameter tubular extension 36 sealed at one end, forming a safety cover for the now exposed tip 21 of the needle. The smaller diameter tubular extension 36 is confluent with a larger diameter tubular extension 34. The open end of the latter contacts the syringe barrel at surface 41 when the assembly-cap-sheath combination, 37-39-16, are in place.
The enclosure 37 including its length and the relative diameter of tubular extension 36, can be designed so that the outside surface of the face portion of cap 39 (corresponding to surface 31--see FIG. 1) contacts the interior surface of the vertical section (as seen in FIG. 4) disposed between the tubular extensions 34 and 36 and before arms 40 ever reach the closed ends of the slots. This design, alternately, can maintain the safety needle cap assembly in a ready condition.
To use the device illustrated in FIGS. 4 and 4A, once the sheath is connected to the hub 20, the operator would grasp the arms 40 extending through the slots 42 in the safety needle enclosure assembly with his or her fingers, then pull the safety needle enclosure 37 off from its contact with the syringe barrel with his or her free hand. With the tip 21 of the needle 22 now exposed and properly aligned, the operator can now proceed with the medical procedure.
As shown in FIG. 5, after the needle is withdrawn from the patient, the elastic tension is released in the elastic sheath 16, which causes the modified safety needle cap 39 to move forward to a position where it encloses the needle tip, the tip of the needle now resting within the cap on the inside surface 46 of the side wall.
In FIGS. 6, 6A and 7, a further version of the invention is illustrated depicting the use of a spring 56 as the elastic sheath means, and illustrating a further modified safety needle cap 54. As described above for FIGS. 4 and 4A a safety needle enclosure assembly 37 encloses the further modified cap 54 and spring elastic sheath 56. One or more arms 58 on the further modified cap project through matching slots 42 in the safety needle enclosure assembly, thereby putting compression tension on the spring 56. Needle 50 is aligned with rear opening 66. The needle is axially aligned with a smaller internal needle opening 64 and a larger, exterior frusto-conical needle opening 62 in a front face portion 63 of cap 54 so that the needle extends through the cap with the tip of the needle 60 now exposed beyond the cap 54, but protected by the tubular extension 36 of the safety needle enclosure assembly 37. The principal modification shown to the cap 54 is that, instead of having a fully opened rear portion of the cap as described in FIGS. 1-5, the rear portion of the cap is substantially closed, by a back face portion 67 which includes a tubular extension 65 having an opening 66. One end of the spring 56 is attached to this tapered tube 65 again in any convenient manner, such as adhesively or with a clamp (not shown), with the other end of the spring 56 similarly attached to needle-hub 50. The spring can be enclosed in a sleeve 69 made of compliant material such as nylon or the like, or even an elastomeric material, such as latex. One end of the fabric enclosure is attached to the extension 65 and the other end to needle hub 50. The spring 56 itself can be fabricated in a variety of suitable materials, including metal or plastic.
As can best be seen in FIG. 6, with the arms 58 secured in the slots 42 within the safety needle enclosure assembly 37, and the one end of the assembly 37 in contact with the surface 71 of the syringe 48, the spring 56 is put under elastic tension. The needle 52 enters the cap through the opening 66 in the tubular extension 65 of the cap 54 and is axially aligned with the internal needle opening 64 and external needle cap opening 62, with the tip 60 of the needle now protruding into the smaller diameter portion 36 of the safety needle enclosure assembly 37. Operator manipulations of the arms 58 and removal of the safety needle enclosure assembly 37 now permits direct utilization of the syringe 48 in the delivery of a medical procedure to a patient.
As illustrated in FIG. 7, after the needle is withdrawn from the patient, the spring tension is released, and the tip 60 of the needle now automatically is positioned within the further modified safety needle cap 54. The opening 64 in the front of the cap and the opening 66 at the rear of the cap are now misaligned to a degree that virtually precludes any possibility of accidentally realigning the needle with the opening 64.
FIGS. 8 and 9 illustrate the second version of the invention depicted in FIGS. 4, 4A and 5 in actual use on a patient. The tip 21 of the needle is shown penetrating the skin on the arm 78 of a patient with the lower bottom edge 38 of the tubular shaped modified safety needle cap 39 in contact with the skin. This serves to aid in maintaining the cap in a withdrawn position, thus sustaining the tension in the elastic sheath means 16 while a medical procedure is in progress. Once the procedure is completed and the needle withdrawn, FIG. 9, the safety needle cap of the invention snaps over the tip of the needle, safely enclosing the potentially dangerous needle.
FIGS. 10 through 12 depict supplementary adaptations of the cap member which, if necessary, could be used to ensure the capture of the needle tip after use. FIGS. 10, 11(a),(b) and 12(a)(b) illustrate a modified version of the safety cap 79. This modification depicts the incorporation of a closure means 80 including a flap member 82 hinged at 84 to the sidewall 86. The flap member is of sufficient size and hinged to the sidewall in a mmaner that it closes off the interior side 88 of the opening 90 when the cap-sheath assembly is in its extended position as shown in FIG. 12(a) and 12(b). FIG. 10 shows the relationship of the flap member 82 to the needle 92 when the cap-sheath assembly is first connected to the needle-syringe assembly. The needle contacts surface 94 of the flap member and captures the flap member 82 between itself and the sidewall 96. This permits the subsequent operation of aligning the needle 92 with the opening 90 in readying the syringe-sheath assembly for use.
FIG. 11(a) and 11(b) indicate the relationship when the needle is axially aligned and positioned through the opening 90. In this view, the flap member 82 rests on the surface of the needle 92.
The hinged flap member can be included as part of the plastic mold used in forming the cap so that the formed cap product would include the flap member as an integral part. The flap member can be employed with any of the cap members, 18, 39 and 54 described above or as described below in FIG. 15.
FIG. 13 illustrates the use of an annular ring of styrofoam or similar material 98 to capture and retain the needle point after the medical procedure. The ring is placed inside the cap and secured with appropriate means such as adhesive, at the juncture between the sidewall and interior surface of the face portion. The annular ring as positioned and constructed of course, would permit needle access to opening 100 during set up.
FIGS. 14(a) and 14(b) disclose in close-up a cap member 102 which depicts the preferred construction of the frusto-conical opening 104 in the front face portion 106 and how gauze 108 or other similarly, absorbent material is disposed therein. The gauze is positioned in the frusto-conical opening and secured by a suitable adhesive. Although the cap style depicted is similar to cap 54 above, the configuration of the opening 104 is also appropriate, of course, for the front face portion of any cap configuration including 18 and 39 described earlier or as described below for the cap design of FIG. 15.
The opening 104 includes a first, larger opening 110, which tapers back to a second opening 112, which may be further reduced in size to a third opening 114 by an annular shelf portion 116. The shelf portion can be included in the cap design, if necessary, to facilitate the placement and retention of the gauze 108. Of course, third opening 114 is of sufficient diameter to permit passage therethrough of the particular needle to be used. Preferably the diameter of the first opening 110 is sufficiently large, so that droplets of body fluid which may adhere to the needle as it is withdrawn from the patient do not bridge the space between the needle and the outer surface 118 of the face portion 106.
FIG. 14(b) is also helpful in illustrating an important feature of the style cap depicted (and style 54 of FIG. 6). Tubular extension 120 formed in back face portion 122, is centered on axis 124 which is offset in relation to the axis of the frusto-conical opening 104 on the front face portion. Both before readying the cap-sheath assembly and the needle-syringe assembly prior to use, and after withdrawing the needle from the patient when the sheath means relaxes and the needle tip is captured within the volume defined by the front face portion 106, back face portion 122 and the sidewall 126, the tubular extension 120 serves a useful purpose. The tubular extension 120 and more particularity the angular orientation of back face portion 122 in relation to the front face portion, ensures that the needle is orientated in a direction essentially parallel to axis 124, and necessarily, is, offset to the axis 128 that the needle aligns itself to when it is inserted through the opening 114. In effect, the cap 102 pivots about the needle 130 at point 132 of the opening 134 on the interior surface 136 of the back face portion 122 whenever the needle tip is positioned in the interior volume 138 as defined by the face portions and sidewall. This occurs, again, prior to readying the assembled cap-sheath-needle-syringe assembly and after the relaxed sheath means moves the cap forward, after use, and the needle enters the volume 138, offset from axis 128. This precludes reentry through opening 114.
Finally, referring for the moment to FIGS. 10 and 12(b) assume the sheath means therein depicted, 140, is fabricated from an elastomeric material such as latex. For the particular cap design illustrated and cap design 18 and 39 above, i.e. designs without the back face portion such as 122 in FIG. 14(b), it is of benefit, depending on its thickness and material, that the elastomeric sleeve tends to arc, as depicted, due to the weight of the cap when the needle withdraws into the interior volume of the cap. Thus in this relaxed state the effect of gravity can cause the cap end the sheath to droop or arc so that the needle opening 100 within the cap is offset from axial alignment with the needle 92. Alternately, the elastomeric sleeve can be formed at manufacture to include the arc. This inherently results in the opening in the cap, 90, being offset to the axis of the needle, thus advancing the purposes of the invention.
FIG. 13 depicts an alternate sheath means 142. The sheath means in this embodiment is fabricated with a suitable bend 146 formed in the material to ensure that opening 100 will be offset from the needle axis when the needle tip is positioned within the cap volume.
In order to provide the offset from the needle axis as required, yet another embodiment as seen in FIG. 15 depicts the cap 148 as fabricated with an angular offset 150 between a front portion 152 and rear portion 154. Here, of necessity, irrespective of the orientation assumed by the sheath means 156 in the relaxed condition, the needle 158 is offset from the axis 160 of the opening 162. The needle is thus precluded from re entering the opening unintendedly.
Thus, it can be seen that a new and economical safety device is provided to health professionals in the utilization of virtually any type of syringe. The safety needle cap-sheath assembly of the invention can be supplied either for field connection to existing syringe and needle assemblies, or, of course, as a complete package including the needle and syringe. In use, the instant invention provides the new and important advantage of safely enclosing a potentially dangerous, used needle, automatically, without any necessity for conscious safety precautions on the part of the health professional.
While the present invention has been disclosed in connection with versions shown and described in detail, various modifications and improvements will become readily apparent to those skilled in the art. Accordingly, the spirit and scope of the present invention is to be limited only by the following claims.
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A safety needle cap assembly for needles is described. In place of the usual safety cap which requires a doctor, dentist or nurse to manually place it in position on a used syringe needle, the safety needle cap assembly of the invention automatically caps the used needle the instant the needle is withdrawn from the patient. An elastic sheath or spring attached to a safety needle cap is kept under tension, retracting the cap and allowing the needle tip to be exposed. Once used and removed from the patient, the elastic tension is released, causing the safety needle cap to snap over the used needle tip automatically, without any operator assistance. The design of the safety needle cap assembly as described virtually preclude accidental re-emergence of the used needle tip during disposal of the needle-cap assembly.
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FIELD
[0001] This present invention relates generally to a fastener machine and more particularly to a die for a rivet machine.
[0002] Rivet machines generally include a ram or punch that is configured to engage and drive a rivet through workpieces to join the workpieces together. In general, when the rivet is driven into the workpieces by the punch, the rivet will urge portions of the workpiece, or a slug, into an opening of the die to make room for the rivet. In some instances, the slug may unfavorably become attached or stuck to the workpiece and/or against the rivet. In such an event, the slug may be carried on the workpiece with the finished component and later fall off. In some examples, the slug may fall off of a workpiece that has been assembled into a completed product (such as a door of a vehicle) that could later cause mechanical problems and/or noise from rattling.
[0003] In accordance with the present invention, a rivet machine is provided. The rivet machine employs a die including a die body that has an inner wall with a pair of retaining ribs or projections extending inwardly therefrom. In use, the rivet pushes a slug from a workpiece within which it is mounted and into an opening of the die. The projections engage and retain the slug within the inner wall. According to further aspects, the pair of retaining ribs are diametrically opposed around the inner wall. Each of the retaining ribs has two converging surfaces that form an angle of between 90 and 150 degrees. In yet another aspect, the projections can be discontinuous such that a first retaining rib is longitudinally offset on the inner wall from a second retaining rib.
[0004] Further advantageous and areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention.
DRAWINGS
[0005] The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure.
[0006] FIG. 1 is a perspective view showing a rivet machine;
[0007] FIG. 2 is a partial cross-sectional view taken through the rivet machine of FIG. 1 ;
[0008] FIG. 3 is a perspective view of a die of the rivet machine shown in FIG. 1 ;
[0009] FIG. 4 is a top plan view of the die of FIG. 3 ;
[0010] FIG. 5 is a longitudinal cross-sectional view of the die taken along line 5 - 5 of FIG. 4 ;
[0011] FIG. 6 is a detail view of an upper portion of the die of FIG. 5 ;
[0012] FIG. 7 is a first side view of the die of FIG. 3 ;
[0013] FIG. 8 is a second side view of the die of FIG. 3 ;
[0014] FIG. 9 is a third side view of the die of FIG. 3 ;
[0015] FIG. 10 is a bottom plan view of the die of FIG. 3 ;
[0016] FIGS. 11-15 illustrate an exemplary sequence for driving a rivet into first and second workpieces according to one example of the present teachings;
[0017] FIG. 16 is a perspective view of a rivet shown driven into the first and second workpiece according to the present teachings;
[0018] FIG. 17 is a prior art view of a slug that has remained attached to a newly introduced rivet;
[0019] FIG. 18 is a cross-sectional view of a die button constructed in accordance to additional features of the present teachings; and
[0020] FIG. 19 is a cross-sectional view of a die button constructed in accordance to other features of the present teachings.
[0021] Corresponding reference numerals indicate corresponding parts throughout the several views of the drawings.
DETAILED DESCRIPTION
[0022] Example embodiments will now be described more fully with reference to the accompanying drawings.
[0023] Referring to FIG. 1 , a rivet setting machine 21 includes a C-frame 23 which is mounted to an articulated robotic arm 25 for automated movement between various operating positions within an industrial factory. An anvil section 27 of C-frame 23 has a die 29 mounted thereon. A ram assembly 31 is mounted to the opposite end of C-frame 23 and includes an air-over-oil fluid actuated cylinder 33 , a nose piece 35 and a linearly moving punch 37 . Alternately, cylinder 33 can be solely hydraulically, pneumatically, or less preferably, servo-motor actuated. A rivet feeding mechanism 41 is mounted to a generally middle segment of C-frame 23 and is elongated in a direction generally perpendicular to the movement direction of punch 37 .
[0024] A vibratory bowl 43 supplies individualized fasteners, such as a self-piercing rivet 45 , to feeding mechanism 41 via a pneumatically pressurized and flexible hose 47 . When multiple workpiece sheets 49 are inserted between punch 37 and die 29 , punch 37 will thereafter push and set the rivet into the upper surface of the workpieces as they are being compressed against die 29 . Self-piercing rivet 45 is preferably a solid (e.g., not hollow) rivet which punches out a blank or slug ( 150 , FIG. 13 ) from the previously unpunched workpiece areas, whereafter the blanks are withdrawn through an aperture in die 29 as will be described in greater detail herein. The rivet ends are generally flush with the adjacent outside surfaces of workpieces 49 . One such self-piercing rivet is disclosed in U.S. Pat. No. 4,130,922 entitled “Headless Riveting System” which issued to Koett on Dec. 26, 1978, which is incorporated by reference herein.
[0025] With particular reference now to FIGS. 3-9 , the die 29 constructed in accordance to one example of the present teachings will be described in greater detail. The die 29 generally comprises a die body 50 having a main body portion 52 and a base portion 54 . A transition between the main body portion 52 and the base portion 54 is generally provided by a skirt 56 . The skirt 56 includes a relief 60 having a ledge 62 . According to one example, the ledge 62 can be engaged by a head of a fastener (not specifically shown) that mechanically secures the die body 50 to a die block 66 provided on the anvil section 27 (See FIG. 2 ). The main body portion 52 generally includes flats 70 formed thereon. The main body portion 52 can further include a die button 71 . The die button 71 generally includes an end surface 72 and a raised collar 74 extending proud therefrom.
[0026] The die body 50 defines an opening 78 . The opening 78 can be generally defined by a bore 79 having an inner wall 80 having a generally cylindrical shape and defining an axis 81 . The inner wall 80 of the die body 50 includes a plurality of retaining ribs or projections collectively identified at reference numeral 82 . The projections 82 extend generally inwardly from the inner wall 80 of the die body 50 . The projections 82 include a first pair of projections 84 , a second pair of projections 86 , and a third pair of projections 88 . In the specific example shown, the projections of the respective pairs of projections 84 , 86 , and 88 are diametrically opposed on the inner wall 80 . According to one example, the projections 82 may be formed on the inner wall 80 of the die body 50 by a wire electrical discharge machining (EDM) process.
[0027] With particular reference now to FIG. 4 , one of the projections 84 of the projections 82 will be described in greater detail with the understanding that the other projections 86 and 88 of the projections 82 may be constructed similarly. The flute 84 generally comprises a first converging surface 90 and a second converging surface 92 . The first and second converging surfaces 90 and 92 generally cooperate to form a pie or triangular shape. In one example, the first converging surface 90 and the second converging surface 92 form an angle 98 of between 90 and 150 degrees, and more specifically, 120 degrees. The projections 82 generally initiate at the inner wall 80 that defines a first diameter 100 and terminate at a second diameter 102 . According to one example of the present teachings, the first diameter 100 can be substantially about 0.266 inches and the second diameter can be about 0.246 inches. In this regard, the second diameter 102 can be substantially between 90 and 95 percent of the first diameter 100 . As will be described more fully herein, the projections 82 can cooperate to retain a slug subsequent to insertion of a rivet into a workpiece. In this regard, the projections 82 of the die body 50 cooperate to inhibit a slug from unfavorably sticking to or otherwise be attached to the workpiece adjacent to a self-piercing rivet.
[0028] Turning now to FIGS. 5 and 6 , additional features of the die body 50 will be described. The die body 50 defines a die chute 110 therethrough. The die chute 110 generally extends the entire length of the die body 50 through the main body portion 52 , the skirt 56 , and the base portion 54 . The die chute 110 is generally coaxial with the opening 78 . As will become appreciated from the following discussion, the die chute 110 can be configured to generally accept slugs therethrough subsequent to a rivet installation. In one example, the die chute 110 can define an inner diameter 111 . The inner diameter 111 can be about 0.30 inches. The raised collar 74 includes surfaces 112 that generally converge at an angle 116 . In one example, the angle 116 can be about 20 degrees. The raised collar 74 can extend proud from the end surface 72 a distance 120 . The distance 120 can be about 0.025 inches.
[0029] Turning now to FIGS. 11-15 , an exemplary sequence for driving a rivet 45 into a first and second workpiece 142 and 144 , respectively will be described. The rivet 45 is a self-piercing rivet. FIG. 11 generally illustrates a rivet 45 intermediate the nosepiece 35 (as well as the punch 37 ) and the die 29 . FIG. 12 illustrates the first and second workpieces 142 and 144 , respectively being located generally between the die 29 and the nosepiece 35 (as well as the punch 37 ). In one example, the second workpiece 144 can be located against the raised collar 74 . As is generally known in the art, the self-piercing rivet 45 can be driven through the first and second workpieces 142 and 144 to join the first and second workpieces 142 and 144 together.
[0030] FIG. 13 illustrates the punch 37 initially driving the rivet 45 through the first workpiece 142 and partially into the second workpiece 144 . The driving of the rivet 45 into the first and second workpieces 142 and 144 creates a slug generally identified at reference numeral 150 . The slug 150 generally comprises a first slug portion 152 and a second slug portion 154 . As can be appreciated, the first slug portion 152 includes material from the first workpiece 142 while the second slug portion 154 includes material from the second workpiece 144 . As shown in FIG. 14 , the rivet 45 has been driven through the second workpiece 144 causing the slug 150 to be generally received into the opening 78 of the die body 50 . At this point, an outer surface of the slug 150 is engaged by the projections 82 extending from the inner wall 80 of the die body 50 . The projections 82 cooperate to generally retain the slug 150 within the opening 78 . In this regard, when the workpieces 142 and 144 are shifted away carrying the newly introduced rivet 45 , the slug 150 is specifically retained by the opening 78 in the die body 50 such that the slug 150 is inhibited from sticking to or otherwise being captured against the newly introduced rivet 45 (as illustrated in FIG. 17 ).
[0031] With reference to FIG. 15 , a subsequent rivet 45 ′ is shown being introduced through the first and second workpieces 142 and 144 . In one example, the workpieces 142 and 144 may have been shifted away from alignment between the punch 37 and the die 29 carrying the previously introduced rivet 45 . The subsequent rivet, identified at reference numeral 45 ′ can drive a new slug identified at reference numeral 150 ′ into the opening 78 of the die body 50 . The new slug 150 ′ will tend to urge the previously retained slug 150 into the die chute 110 , where it may be collected with other slugs in the sequence. The process then repeats itself with each subsequent rivet introduction. In some examples, a vacuum may be attached to the die body 50 for drawing air through the die chute 110 in a direction generally from the opening 78 at the main body portion 52 in a direction toward the base portion 54 . FIG. 16 illustrates the rivet 45 installed into the workpieces 142 and 144 .
[0032] FIG. 18 illustrates a die 229 constructed according to additional features. The die 229 includes a die body 250 and die button 271 . The die button 271 has a raised collar 274 . An opening 278 is generally defined by a bore 279 having an inner wall 280 . Projections, collectively identified at 282 extend inwardly from the inner wall 280 . The projections 282 can include a first projection 284 that is discontinuous from a second projection 286 . The projections 282 can extend at an angle relative to an axis of the inner wall 280 . Projections 282 ′ having first projection portion 284 ′ and second projection portion 286 ′ are shown in a die 229 ′ configuration in FIG. 19 . The projections 282 ′ are parallel to an axis of an inner wall 280 ′.
[0033] The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure.
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A rivet machine is provided. The rivet machine employs a die including a die body that has an inner wall with a pair of retaining ribs or projections extending inwardly therefrom. In use, the rivet pushes a slug from a workpiece within which it is mounted and into an opening of the die. The projections engage and retain the slug within the inner wall. According to further aspects, the pair of retaining ribs are diametrically opposed around the inner wall. Each of the retaining ribs has two converging surfaces that form an angle of between 90 and 150 degrees. In yet another aspect, the projections can be discontinuous such that a first retaining rib is longitudinally offset on the inner wall from a second retaining rib.
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This application claims priority to provisional application Ser. No. 61/725,566, filed on Nov. 13, 2012 and to provisional application Ser. No. 61/818,479, filed on May 2, 2013, the contents of both of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
This invention relates to leak detection and more particularly to a leak detection apparatus based on the presence of a pressure gradient near a leak within a pipe.
Potable water obtained through access of limited water reserves followed by treatment and purification is a critical resource to human society. Failure and inefficiencies in transporting drinking water to its final destination wastes resources and energy. In addition to that, there are thousands of miles of natural gas and oil pipelines around the globe that are poorly maintained. Thus, a significant portion of the total oil and natural gas production is lost through leakage. This is causing, among others, threats for humans and environmental damage.
There are various out of pipe techniques reported in the literature for leak detection [1, 2]. First, leak losses can be estimated from audits. For instance in the water industry, the difference between amounts of water produced by the water utility and the total amount of water recorded by water usage meters indicates the amount of unaccounted water. While this quantity gives a good indication of the severity of water leakage in a distribution network, metering gives no information about the locations of the leaks.
Acoustic leak detection is normally used not only to identify but also to locate leaks. Acoustic methods consist of listening rods or aquaphones. These devices make contact with valves and/or hydrants. Acoustic techniques may also include geophones to listen for leaks on the ground above the pipes [2]. Drawbacks of those methods include the necessary experience needed by the operator. The method is not scalable to the network range since the procedure is very slow.
More sophisticated techniques use acoustic correlation methods, where two sensors are placed on either side of the leak along a pipeline. The sensors bracket the leak and the time lag between the acoustic signals detected by the two sensors is used to identify and locate the leak [3]. This cross-correlation method works well in metal pipes. However, a number of difficulties are encountered in plastic pipes and the effectiveness of the method is doubtful [4, 5].
Finally, several non-acoustic methods like infrared thermography, tracer gas technique and ground-penetrating radar (GPR) have been reported in the literature of leak detection [6, 7]. Those methods have the advantage of being insensitive to pipe material and operating conditions. Nevertheless, a map of the network is needed, user experience is necessary and the methods are in general slow and tedious.
Past experience has shown that in-pipe inspection is more accurate, less sensitive to external noise and also more robust, since the detecting system will come close to the location of the leaks/defects in the pipe. Various in-pipe leak detection approaches will now be discussed.
The Smartball is a mobile device that can identify and locate small leaks in liquid pipelines larger than 6″ in diameter constructed of any pipe material [8]. The free-swimming device consists of a porous foam ball that envelops a watertight, aluminum sphere containing the sensitive acoustic instrumentation.
Sahara is able to pinpoint the location and estimate the magnitude of the leak in large diameter water transmission mains of different construction types [9]. Carried by the flow of water, the Sahara leak detection system can travel through the pipe. In case of a leak, the exact position is marked on the surface by an operator who is following the device at all times. Both Smartball and Sahara are passive (not actuated) and cannot actively maneuver inside complicated pipeline configurations. Last, operator experience is needed for signal extraction and leakage identification and localization.
Our group at the Massachusetts Institute of Technology has proposed a passive inspection system for water distribution networks using acoustic methods [10]. This detection system is designed to operate in small pipes (4″). The merits of the in-pipe acoustic leak detection under different boundary conditions are reported in [11, 12].
Under some circumstances it is easier to use remote visual inspection equipment to assess the pipe condition. Different types of robotic crawlers have been developed to navigate inside pipes. Most of these systems utilize four-wheeled platforms, cameras and an umbilical cord for power, communication and control, e.g. the MRINSPECT [13]. Schemph et al. report on a long-range, leak-inspection robot that operates in gas-pipelines (the Explorer robot) [14]. A human operator controls the robot via wireless RF signals and constantly looks into a camera to search for leaks. Such systems are suitable for gas or empty liquid pipelines (off-line inspection).
In the oil industry several nondestructive testing methods are used to perform pipe inspections. Most systems use Magnetic Flux Leakage (MFL) based detectors and others use ultrasound (UT) to search for pipe defects [15]. These methods' performance depends on the pipe material. They are also power demanding, most of the times not suitable for long-range missions and have limited maneuvering capabilities because of their large sizes.
An object of the present invention is an apparatus to perform autonomous leak detection in pipes that eliminates the need for user experience.
SUMMARY OF THE INVENTION
The leak detection apparatus for deployment in a pipe according to the invention includes a carrier disposed for motion along the pipe, and a detector connected to move with the carrier in an axial direction. The detector includes a drum mounted for rotation about pitch and yaw axes and a flexible material is mounted on and extends from the drum. At least two sensors are provided responsive to drum rotation. The flexible material will be drawn into contact with a wall of the pipe at a leak location, thereby producing a torque on the drum, causing the drum to rotate and the at least two sensors to generate signals from which leak location is determined.
In a preferred embodiment, the leak detection apparatus further includes a gimbal disposed between the carrier and detector to allow for drum rotation. A suitable flexible material is polyurethane.
The present invention achieves leak detection based on the presence of a pressure gradient in the neighborhood of a leak. The disclosed leak detector can sense leaks at any angle around the circumference of the pipe with only two sensors.
BRIEF DESCRIPTION OF THE DRAWING
FIGS. 1 and 1A is a schematic, perspective view of an embodiment of the in-pipe leak detection apparatus disclosed herein.
FIG. 2 is a chart illustrating a numerical study of the static pressure distribution in the vicinity of a leak in a water pipe.
FIG. 3 is a graph of radial pressure gradient against radial distance in the vicinity of a 4 mm diameter leak.
FIGS. 4 a, b, c and d are cross-sectional views of a pipe with a detector, according to an embodiment the invention, disposed inside.
FIGS. 5 A and B are perspective and cross-sectional views of a three dimensional solid model embodiment of the leak detector disclosed herein.
FIGS. 6 a,b,c,d,e,f,g and h is an exploded view of an embodiment of the leak detector disclosed herein.
FIGS. 7 A and B is a perspective and cross-sectional view illustrating forces acting on the drum in the presence of a leak.
FIGS. 8 A and B are top and bottom views of the leak detector disclosed herein deployed within a pipe according to an embodiment of the invention.
FIGS. 9 A, B and C is a perspective view of a three dimensional solid model of the carrier module of the leak detector disclosed herein according to an embodiment of the invention.
FIG. 10 is a block diagram showing a high level system architecture of an embodiment of the leak detector disclosed herein.
FIG. 11 is a photograph of the experimental setup used to evaluate an embodiment of the leak detection apparatus disclosed herein.
FIG. 12 is a graph of force against time showing sensor signals as the leak detector disclosed herein moves along a pipe.
FIG. 13 is a graph of force versus time showing sensor signals as the leak detector moves along the pipe.
FIG. 14 is a graph of force versus time showing sensor signals as the leak detector apparatus moves along the pipe.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In this application we introduce PipeGuard, a name adopted by the inventors herein for a new system able to detect leaks in pipes in a reliable and autonomous fashion ( FIG. 1 ). The idea is that the apparatus disclosed herein is inserted into the network via special insertion points, e.g., fire hydrants in water networks. The system inspects the network and sends signals wirelessly via relay stations to a computer [16]. Leak signals stand out clearly on occurrence of leaks, eliminating the need for user experience. The latter is achieved via a detector that is based on identifying a clear pressure gradient in the vicinity of leaks.
The proposed detection concept and the proposed detector design are now discussed. PipeGuard is able to detect leaks in a reliable and robust fashion because of the fundamental principle behind detection. More specifically, the detection principle is based on identifying the existence of a localized pressure gradient ∂p/∂r This pressure gradient appears in pressurized pipes in the vicinity of leaks and is independent of pipe size and pipe material. It also remains relatively insensitive to the fluid medium inside the pipes, which makes the detection method widely applicable (gas, oil, water pipes, etc).
The detection concept is based on the fact that any leakage in a pipeline alters the pressure and flow field of the working medium. Our group studied, characterized and quantified the phenomenon in detail [17]. The main conclusion is that the region near the leak that is affected is small. This region is characterized by a rapid change in static pressure, dropping from PHigh, inside the pipeline, to PLow in the surrounding medium outside ( FIG. 2 ).
This local phenomenon is an important feature in the disclosed leak detection scheme. The rapid change in pressure (radial pressure gradient) due to existence of leaks essentially represents a “suction region”. Numerical studies showed that the radial pressure gradient close to the leak is large in magnitude (O(Δp=p High −p Low )) and drops quickly as distance increases. This is shown in FIG. 3 . More details are reported in [17].
Identifying leaks based on this radial pressure gradient proves to be reliable and effective as shown in this paper. Directly measuring the pressure at each point in order to calculate the gradient is not effective and should be avoided. However, as a leak can happen at any angle around the circumference, full observability would require a series of pressure sensors installed around the circumference of the pipe. To avoid the complexity of such an attempt, we introduce a more efficient mechanism to be discussed below.
We propose a detection concept for the identification of the radial pressure gradient in case of leaks. The main requirement is that the system should be able to detect leaks at any angle φ around the circumference of the pipe.
A schematic of the proposed detection concept is shown in FIG. 4 . To achieve full observability around the circumference a circular membrane is utilized. The membrane is moving close to the pipe walls at all times conforming to diameter changes and other defects on the walls, e.g. accumulated scale. The membrane is suspended by a rigid body, called a drum ( FIG. 4 [ a ]). The drum is allowed to rotate about its center point G (about any axis) by design. The latter is allowed by a gimbal.
In case of a leak the membrane is pulled towards it. This happens because the membrane is pulled by the radial drop in pressure ∂p/∂r described earlier ( FIG. 4 [ b )). Upon touching the walls, pressure difference Δp is creating the normal force F on the membrane. We can write that:
F=ΔpA Leak (1)
where A Leak stands for the cross-sectional area of the leak, which can be of any shape.
As PipeGuard continues traveling along the pipe, a new force is generated (F z ). This force is a result of friction between the membrane and the pipe walls. F z is related to the normal force, F, by an appropriate friction model, say F z =g(F). The analytic form of function g is not discussed in this patent application. By using Eq. (1) we can see that F z depends on the pressure difference, since F z =g(ΔpA Leak ).
Then F z generates an equivalent force and torque on the drum, M, a key fact that is discussed further below. As a result, M pushes the drum to rotate about some axis passing through its center, while orientation of the axis depends on the angle φ of the leak around the circumference ( FIG. 4 [ c ]). The effects of M can be later sensed by force and/or displacement sensors mounted on the detector. F z vanishes only when the membrane detaches from the leak and the drum bounces back to the neutral position ( FIG. 4 [ d ]).
We now describe the detailed design of a mechanism that uses the concept presented here to effectively identify leaks in pipes. The disclosed system can identify a leak by measuring forces on the drum. Essentially, the problem has switched from identifying a radial pressure gradient (at any angle φ), to measuring forces (and/or deflections) on a mechanism.
A 3D solid model of the disclosed detector is shown in FIG. 5 . The exploded view of the design is presented in FIG. 6 . The drum is suspended by a wheeled system and remains always in the middle of the pipe. A key fact with this design is the gimbal mechanism consisting of two different parts (parts [b] and [c] in FIG. 6 ). This mechanism allows the drum to pivot about two axes and thus respond to any torque, M, about any axis passing through its center point G. Moreover, the system dimensions are such that the membrane leaves a small clearance (<2 mm) from the walls of the pipe.
Whenever a leak exists, a torque M is generated about some axis on the drum depending on the leak angle φ, as described earlier. M is sensed by appropriate sensors on the back plate on the carrier. Very small motions on the drum are allowed in this specific embodiment. Springs (not shown) are used in order to push the drum back to the neutral position after detection is completed ( FIG. 4 [ d ]. In this embodiment three linear springs are used and they are omitted in all figures for simplicity.
We now present the forces acting on the drum and justify the placement of sensors on the detector. In addition we propose a detection algorithm for effective leak detection and identification.
We discussed earlier that a force F z =F z ê z , is generated at leak positions. Here we use ê z to represent the unit vector along axis z and similar notation will be followed. This force is then generating a torque about point G, the center of the gimbal mechanism, which is equal to:
M
=
F
z
R
=
F
z
R
(
cos
ϕ
e
^
y
-
sin
ϕ
e
^
x
)
(
2
)
The drum is supported by three points, namely point A, B and C ( FIG. 7 ). The distance between each of these points and the center of the gimbal G is the same and equal to r. We mention at this point that three points of support is the minimal support that is needed to fix the gimbal mechanism in position in such a design. In addition, those points are 2π/3 away from each other.
We need to mention at this point that the three points do not contribute to the support of the drum at the neutral position. When the drum tends to move from neutral position each support creates a corresponding normal force (F A , F B , F C ) to counterbalance torque M stemming from F z . We can write:
M x =[F A r −( F B +F C ) r sin(π/6) ê x (3)
M y =[F B −F C ]r cos(π/6)] ê y (4)
And the total support torque is equal to:
M support =M x +M y (5)
We assume here that the drum is only allowed to perform small movements and, thus, static analysis is accurate to first order. To complete the analysis we need to equilibrate the torques and forces acting on it. To do this we need to set M support =M, using Eq. (2,5,3,4).
In addition, since the drum is only allowed to move very little, we can assume that F z is balanced by the support provided by the axes of the gimbal at point G. Then the sum of the three support forces discussed here is approximately equal to zero:
F A +F B +F C =0 (6)
One can solve the system of equations for the three unknown support forces. Solution to system of equations yields:
F
A
=
-
2
R
sin
ϕ
3
r
F
z
e
^
z
(
7
)
F
B
=
2
R
sin
ϕ
+
3
cos
ϕ
6
r
F
z
e
^
z
(
8
)
F
C
=
2
R
sin
ϕ
-
3
cos
ϕ
6
r
F
z
e
^
z
(
9
)
For the purpose of this work we built a prototype that has the following dimensions:
R=47 mm r=12.5 mm
and the detector is designed to operate in 100 mm as discussed later.
By installing two force sensors on the supports we are able to measure the corresponding forces directly. The idea here is to measure the support forces as a results of the leak force F z , instead of measuring the leak pressure gradient directly.
To avoid “blind spots” and to be able to detect leaks at any angle around the circumference the system needs to perform at least two force measurements. The latter statement needs to be proven via observability analysis, which is outside the scope of this application. However, one can think of the simple case of a single leak at φ=0°. In such case a force sensor installed on point A would not give any measurement (F A =0). However, another sensor placed on either point B or C can measure forces due to the leak and can eventually identify it.
In this embodiment we install force sensors on points B and C without loss of generality. In addition we propose the use of the following metric in order to effectively trigger alarms in case of leaks:
J ( t,T )=∫ t-T t √{square root over ( F B (τ) 2 +F C (τ) 2 )}{square root over ( F B (τ) 2 +F C (τ) 2 )} dτ (10)
where T is the integration period. Whenever J(t, T)>c, where c is a predefined constant, a leak is identified. c needs to be selected in such a way to neglect noise and avoid false alarms. At the same time large values of c will lower the sensitivity of the detection. This metric proves to be effective in identifying leaks in pipes as shown below where we present experimental results.
In order to validate the concepts we developed a prototype that will now be discussed. PipeGuard is evaluated in a real gas pipe. Details of the experiments and results are shown below.
For this work PipeGuard is designed to operate in 4″ (100 mm) ID gas pipes. However, all concepts discussed herein can be scaled and slightly altered accordingly to accommodate pipes of different sizes and perform leak inspection in other fluid media, e.g. water, oil, etc.
In this embodiment PipeGuard consists of two modules, namely the carrier and the detector ( FIG. 8 ). The detector design and concepts have been discussed in detail earlier.
The carrier assures the locomotion of the system inside the pipe. The module is carrying actuators, sensors, power and also electronics for signal processing and communications. A 3D solid model of the carrier with explanations on its main subsystems is presented in FIG. 9 .
The module's locomotion is provided via a pair of traction wheels (OD=1 3/16″ ) ( FIG. 9 ). Those two wheels are touching the lower end of the wall. In addition, the system is suspended by 4 legs with passive wheels from the upper walls as shown in the same figure.
Each suspension wheel has a spring loaded pivot. The angle θ sus of each pivot point on each suspension wheel is regulated in a passive way and is providing required compliance to the carrier. That compliance is very important, since it enables the module to align itself properly inside the pipe, overcome misalignments or defects on the pipe walls or even comply with small changes in the pipe diameter.
The main actuator of the module is a 20 W brushed DC Motor from “Maxon” (339150). The motor is connected to the traction wheels via a set of gears with ratio 5:1. In order to regulate speed, an incremental rotary encoder (50 counts) from “US Digital” is used and the speed loop is closed. Both disk and hub are shown in FIG. 9 . Finally, all electronics, communication modules and batteries are stored inside the carrier module.
Derived from our design requirements, the robot should be able to perform the following tasks:
Move and regulate speed in pipes Identify leaks by measuring signals from two force sensors at relatively high sampling rates (f s >150 Hz). Communicate with the Command Center wirelessly
PipeGuard's architecture is developed to meet these requirements and is shown in FIG. 10 . To perform the aforementioned tasks two micro-controllers are used. Micro-controller # 1 is dedicated to speed regulation and micro-controller # 2 is performing real-time leak sensing.
The workflow is the following: The user specifies a motion command on the computer. The computer sends out the motion command including desired speed and desired position to PipeGuard. After the WiFi transceiver on the robot receives the command, it delivers the command to micro-controller # 2 . Micro-controller # 2 performs closed loop speed control in order to regulate speed of the carrier. At the same time it calculates speed (by measuring the signal from the encoder) and commands the system to stop if it reaches the end of the pipe section (or any other point along the pipe as specified by the operator).
Parallel to micro-controller # 2 , micro-controller # 1 is responsible for leak detection and for sending out sensor data to the WiFi transceiver. This micro-controller receives signals from the two force sensors installed on the detector. At the same time it receives the measured position from the encoder mounted on the carrier. It compiles the correlating force sensor data with position data and sends them out through the WiFi transceiver. The WiFi receiver on the command center then receives the data, decomposes them and supplies them to the user via the graphical user interface on the computer.
In this embodiment of PipeGuard, the WiFi transceiver selected is an Xbee Pro 900 MHz RP module. We use two Arduino Pro Mini 328 5V/16 MHz and the motor driver used is the VNH5019 from Polulu. The whole system is powered by a 11 0.1 V 350 mAh 65 C Li-polymer battery. Finally, we use two FSR 400 force sensors for leak detection from “Interlink Electronics”. The latter ones are powered at 5V and a resistor of 8 kΩ is used for the necessary voltage division.
We now evaluate PipeGuard in an experimental setup we built in our lab. The setup consists of a straight 4″ ID and 1.40 m long PVC pipe. The system is deployed in the pipe and performs leak detection in a pressurized gas environment. Artificial leaks have been created on the pipe walls in the shape of circular 2 mm openings. Those openings can be considered small for the general case and such small leaks fail to be detected by most state-of-the-art systems available.
A picture of PipeGuard inside the experimental setup is shown in FIG. 11 . PipeGuard moves along the pipe from [Start] to [End] and its job is to identify the leaks. In FIG. 11 leak # 1 is covered and leak # 2 is opened.
Initially we let the system run in the pipe at low speeds. We command PipeGuard to move at ω d =2 H z . which is equivalent to ν d =0.19 m/s. At this speed the system is able to traverse the distance from [Start] to [End] in approximately 5 sec. The signals captured by the two force sensors are shown in FIG. 12 . A clear change in the signals reveals the existence of a leak in the pipe. Note here that for this experiment the line pressure was selected to be equal to 15 psi. In the same figure the evolution of the proposed metric from Eq. 10 is shown. A clear peak above the noise level is indicating the existence of a leak at t=t* when J(t*, T=0.2 sec)>0.025.
As PipeGuard approaches the leak, the signals from the two force sensors do not show any large variations from the DC value. Noise can occur but is much smaller in amplitude than the leak signal ( FIG. 12 ). Detection occurs in four phases. Initially PipeGuard approaches the leak. Then the membrane is moving towards the leak because of the effect of the radial pressure gradient. The latter small movement results in a small change in the signals (undershoot in this case). Afterwards and when the membrane touches the wall at the leak position a force F z is generated, resulting in the torque M on the drum. The latter torque pushes the drum to move and thus signals of the two sensors change significantly. Signals continue to increase up to a certain point when the membrane detaches from the leak. At this point the drum bounces back to the neutral position and signals return to their dc values.
Successful detection is performed when both leaks along the pipe are opened. Again PipeGuard is commanded to move at ν d =0.19 m/s. The detector passes by the two consecutive leaks and the signals captured are presented in FIG. 13 . Signal magnitude for leak # 1 is smaller than the magnitude for leak # 2 . This is expected, as line pressure at the position of leak # 1 is reduced, because of the existence of leak # 2 . By carefully selecting corresponding thresholds c, one can trigger alarms at times t* i when J(t* i ,T)>c. In this case, again, c=0.025 is selected in order to avoid false alarm (neglect noise) and effectively trigger alarms at leak locations.
By carefully observing FIG. 13 we can see that signals captured as PipeGuard is passing by the first leak are in phase, while the signals at the second leak are out of phase. This occurs because the two leaks are at a different position on the circumference of the pipe (φ 1 ≠φ 2 ). By designing appropriate algorithms one can estimate the position of the leak on the circumference, but such discussion is outside the scope of this application.
This specific version of PipeGuard is able to move inside the pipes at relatively high speeds. Experimentation showed that PipeGuard's motor is saturated at approximately ω d =9.23 H z , which is equivalent to ν d =0.875 m/s. At this speed PipeGuard is able to inspect pipes at a rate of more than 3 km per hour. Even at these speeds PipeGuard is still able to inspect pipelines and detect leaks in a very reliable fashion. By carefully selecting the triggering thresholds one is able to trigger alarms only when leaks are present and avoid false alarms. Example leak signals captured at those high speeds are shown in FIG. 14 . In this case noise magnitude is higher, but still leak signals stand out significantly. In this case c=0.025, but one would probably try to increase the threshold. The latter would enable the sensor to neglect higher noise levels at the cost of reducing the sensitivity of the detection.
The numbers in square brackets refer to the references listed herein. The contents of all of these references are incorporated herein by reference in their entirety.
It is recognized that modifications and variations of the present invention will be apparent to those of ordinary skill in the art, and it is intended that all such modifications and variations be included within the scope of the appended claims.
REFERENCES
[1] Mays L., 2000 . Water Distribution Systems Handbook . McGraw-Hill
[2] Hunaidi O., Chu W., Wang A. and Guan W., 1999. “Leak detection method for plastic water distribution pipes”. Advancing The Science of Water. Fort Lauderdale Technology Transfer Conference, AWWA Research Foundation , pp. 249-270.
[3] Fuchs H. V. and Riehle R., 1991. “Ten years of experience with leak detection by acoustic signal analysis”. Applied Acoustics, 33, pp. 1-19.
[4) Hunaidi O. and Chu W., 1999. “Acoustical characteristics of leak signals in plastic water distribution pipes”. Applied Acoustics, 58, pp. 235-254:
[5) Bracken M. and Hunaidi O., 2005. “Practical aspects of acoustical leak location on plastic and large diameter pipe”. Leakage 2005 Conference Proceedings (448-452).
[6] Hunaidi O., Chu W., Wang A. and Guan W., 2000. “Detecting leaks in plastic pipes”. Journal American Water Works Association, 92(2), pp. 82-94.
[71 Hunaidi O. and Giamou P., 1998. “Ground-penetrating radar for detection of leaks in buried plastic water distribution pipes”. Seventh International Conference on Ground Penetrating Radar ( GPR ' 98), pp. 783-786.
[8) Kurtz D. W., 2006. “Developments in a free-swimming acoustic leak detection system for water transmission pipelines”. ASCE Conf Proc., 25 (211).
[9] Bond A., Mergelas B. and Jones C., 2004. “Pinpointing leaks in water transmission mains”. ASCE Cotif. Proc., 91(146).
[10] Chatzigeorgiou D., Youcef-Toumi K., Khulifa A. and BenMansour R., 2011. “Analysis and design of an in-pipe system for water leak detection”. ASME International Design Engineering Technical Conferences & Design AutomationConference ( IDETC/DAC 20 11).
[11] Khalifa A., Chatzigeorgiou D., Youcef-Toumi K., Khulief Y. and Ben-Mansour R., 2010. “Quantifying acoustic and pressure sensing for in-pipe leak detection”. ASME International Mechanical Engineering Congress & Exposition ( IMECE 20/0).
[12] Chatzigeorgiou D., Khalifa A., Youcef-Toumi K. and Ben Mansour R., 2011. “An in-pipe leak detection sensor: Sensing capabilities and evaluation”. ASMEIJEEE International Conference on Mechatronic and Embedded Systems and Applications ( MESA 2011).
[13] Choi H-R. and Roh S-G, 2005. “Differential-drive in-pipe robot for moving inside urban gas pipelines”. Transactions on Robotics, 21(1).
[14] Schempf H., Mutschler E., Goltsberg V., Skoptsov G., Gavaert A. and Vradis G., 2003. “Explorer: Untethered real-time gas main assessment robot system”. Proc. of Int. Workshop on Advances in Service Robotics ( ASER ).
[15] Mirats Tur, J. M., and Garthwaite, W., 20 I 0. “Robotic devices for water main in-pipe inspection: A survey”. Journal of Field Robotics, 27(4), pp. 491-508.
[16] Wu D., Youcef-Toumi K., Mekon S. Ben Mansour R., 2013. “Relay node placement in wireless sensor networks for pipeline inspection”. IEEE American Control Conference ( ACC 2013).
[17] Ben-Mansour R, M. A. Habib, A. Khalifa, K. Youcef-Toumi and D. Chatzigeorgiou, 2012. “A computational fluid dynamic simulation of small leaks in water pipelines for direct leak pressure transduction”. Computer and Fluids (2011).
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Leak detection apparatus for deployment in a pipe. The apparatus includes a carrier disposed for motion along the pipe and a detector connected to move with the carrier in an axial direction. The detector comprises a drum mounted for rotation about pitch and yaw axes. A flexible material is mounted on, and extends from, the drum and at least two sensors responsive to drum rotation are provided. The flexible material will be drawn into contact with a wall of the pipe at a leak location, thereby producing a torque on the drum, causing the drum to rotate, and the at least two sensors to generate signals from which leak location is determined.
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CLAIM FOR PRIORITY
[0001] This application claims priority from Korean Patent Application Number 2004-57202, filed Jul. 22, 2004 in the Korean Intellectual Property Office (KIPO). We incorporate the 2004-57202 application by reference.
BACKGROUND
[0002] 1. Field
[0003] We describe a frequency divider and, more particularly, a frequency divider with a high speed dual modulus prescaler and an associated method.
[0004] 2. Related Art
[0005] Frequency divider circuits are part of frequency synthesizers. In Radio Frequency (RF) systems, frequency synthesizers generate a local oscillator's frequency to step up or step down a frequency band.
[0006] Frequency synthesizers usually include a Phase Lock Loop (PLL), and generate a frequency different from the frequency of an input signal. The PLL is a basic building block of modern electronic systems. As shown in FIG. 1 , the PLL circuit includes a phase/frequency detector 100 , a charge pump 200 , a loop filter 300 , a Voltage Controlled Oscillator (VCO) 400 , and a frequency divider 500 .
[0007] The phase/frequency detector 100 generates an up-signal SUP and/or down-signal SDN based on a phase difference between a reference signal SIN and a feedback signal SFEED. The charge pump 200 outputs a signal having a level determined by a state of the up-signal SUP and/or the down-signal SDN. The loop filter 300 removes a high frequency component of the signal provided by the charge pump 200 , and provides the input voltage VLF to the VCO 400 . The VCO 400 outputs a high frequency signal having a frequency determined by the direct current level of the input voltage VLF. The frequency divider 500 generates the feedback signal SFEED having a low frequency based on the VCO output signal SOUT. The phase/frequency detector receives the feedback signal SFEED from the divider 500 .
[0008] Downstream circuitry (not shown) use the VCO 400 output signal SOUT for various applications after the PLL circuit is locked. Many embodiments of the frequency divider 500 shown in FIG. 1 currently exist. For example, U.S. Pat. No. 6,696,857 describes the frequency divider shown in FIG. 2 . Referring to FIGS. 1 and 2 , dual modulus prescaler includes D flip-flops 12 and 14 , NMOS transistors MN 1 and MN 2 , a PMOS transistor MP 1 , and a NAND gate 21 .
[0009] The dual modulus prescaler of FIG. 2 receives an output signal SOUT from VCO 400 as an input signal to divide the frequency of the output signal SOUT by 4 or 3, and outputs the feedback signal SFEED.
[0010] The output signal SOUT clocks the D flip-flops 12 and 14 , respectively. The NAND gate 21 , the NMOS transistors MN 1 and MN 2 , and the PMOS transistor MP 1 control the frequency division ratio of the dual modulus prescaler. When a mode signal MODE has a logic level ‘0’, an output signal of the NAND gate 21 has a logic level ‘1’. As a result, the NMOS transistor MN 1 is on and a node B has a logic level ‘0’. At this time, the NMOS transistor MN 2 is off, and a node C is not at GND. Accordingly, the D flip-flops 12 and 14 of the dual modulus prescaler divide the frequency of the input signal by 4.
[0011] When a mode signal MODE has a logic level ‘1,’ on the other hand, and the output signal SFEED of the D flip-flop 14 has a logic level ‘1’, the output signal of the NAND gate 21 has a logic level ‘0’ and the NMOS transistor MN 1 is off. When an inverted output signal of the D flip-flop 14 has a logic level ‘0’, the PMOS transistor MP 1 is on, and node B has a logic level ‘1’ that turns on the NMOS transistor MN 2 . The node C, therefore, is at GND. As a result, the D flip-flops 12 and 14 of the dual modulus prescaler divide the frequency of the input signal by 3. The frequency divider shown in FIG. 2 operates at a speed dependent on the dual modulus prescaler.
[0012] The frequency divider's operating speed depends on a delay time associated with the NAND gate 21 and the NMOS transistors MN 1 and MN 2 , since these components together with the PMOS transistor MP 1 control the frequency division ratio. The delay time is related to the time until the output signal SFEED of the D flip-flop 14 and the mode signal MODE reach a node C.
[0013] The dual modulus prescaler of FIG. 2 is not suitable for a PLL system operating at a high frequency, e.g., in the range of 1 to 10 GHz due to the delay times of the NAND gate 21 and the NMOS transistors MN 1 and MN 2 .
[0014] Accordingly, a need remains for a frequency divider having a dual modulus prescaler capable of operating at high frequencies.
SUMMARY
[0015] We describe a frequency divider including a dual modulus prescaler that seeks to overcome limitations and disadvantages associated with the related art.
[0016] We describe a dual modulus prescaler comprising a frequency division unit to generate a prescaled signal by dividing a frequency of an input signal by a division ratio and a frequency division ratio controller to determine the division ratio responsive to a count signal and the prescaled signal.
[0017] The input signal may be generated by a voltage-controlled oscillator.
[0018] The division ratio may be one of 2N and 2N−1, where N is an integer.
[0019] The frequency division unit comprises N D flip-flops.
[0020] The input signal is adapted to clock the D flip-flops.
[0021] The frequency division ratio controller comprises at least two serially connected transistors.
[0022] The frequency division ratio controller comprises a first NMOS transistor having a drain coupled to an output terminal of a first stage flip-flop in the frequency division unit and a gate to receive either the count signal or the prescaled signal. And a second NMOS transistor has a drain coupled to a source of the first NMOS transistor, a gate to receive the prescaled signal, and a source coupled to a second power supply voltage.
[0023] The frequency division ratio controller comprises a first PMOS transistor having a drain coupled to an output terminal of a first stage flip-flop in the frequency division unit and a gate to receive either the count signal or the prescaled signal. And a second PMOS transistor has a drain coupled to a source of the first PMOS transistor, a gate to receive the prescaled signal, and a source coupled to a first power supply voltage.
[0024] The count signal may be generated responsive to the prescaled signal.
[0025] And we describe a prescaling method of a dual modulus prescaler comprising dividing a frequency of an input signal by a first division ratio responsive to a control signal and a prescaled signal, dividing the prescaled signal by a second division ratio to output the divided signal, and changing a state of the control signal after a predetermined number of clock pulses are generated responsive to the prescaled signal.
BRIEF DRAWINGS DESCRIPTION
[0026] The above and other features and advantages of the present invention will become more apparent by describing in detail example embodiments thereof with reference to the following drawings.
[0027] FIG. 1 is a block diagram illustrating a conventional phase locked loop PLL circuit.
[0028] FIG. 2 is a circuit diagram illustrating a conventional dual modulus prescaler included in the frequency divider of FIG. 1 .
[0029] FIG. 3 is a block diagram illustrating a frequency divider according to an example embodiment of the present invention.
[0030] FIG. 4 is a circuit diagram illustrating a dual modulus prescaler included in the frequency divider of FIG. 3 according to an example embodiment of the present invention.
[0031] FIG. 5 is a timing diagram of the dual modulus prescaler shown in FIG. 4 when a control signal SCON has a low level.
[0032] FIG. 6 is a timing diagram of the dual modulus prescaler shown in FIG. 4 when a control signal SCON has a high level.
[0033] FIG. 7 is a circuit diagram illustrating a dual modulus prescaler included in the frequency divider of FIG. 3 according to another example embodiment of the present invention.
DETAILED DESCRIPTION
[0034] We detail illustrative embodiments in the following description. Our intention is that specific structural and functional details are merely representative of example embodiments. The frequency divider may have many alternate forms and should not be construed as limited to the embodiments set forth here.
[0035] Accordingly, while the frequency divider is susceptible to various modifications and alternative forms, specific embodiments are shown by way of example in the drawings. It should be understood, however, that there is no intent to limit the frequency divider to the particular forms disclosed, but on the contrary, to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the claims. Like numbers in the various drawings refer to like elements in the description.
[0036] FIG. 3 is a block diagram of an embodiment of a frequency divider. Referring to FIG. 3 , the frequency divider 500 includes a dual modulus prescaler 520 , a fixed division ratio scaler 540 , and a control circuit 560 . The dual modulus prescaler 520 receives a signal SOUT output from a VCO (not shown). The prescaler 520 divides the frequency of the output signal SOUT by 2N or 2N−1 under the control of a control signal SCON and a prescaled signal PDIV. The fixed division ratio scaler 540 divides the frequency of the prescaled signal PDIV by a predetermined division ratio 1/M and outputs a feedback signal SFEED. The control circuit 560 counts the number of rising edges of the prescaled signal PDIV. The control circuit 560 generates the control signal SCON having a first level, e.g. high, when the number of counted clock pulses reaches a predetermined value. The control circuit 560 provides the control signal SCON to the dual modulus prescaler 520 . The control circuit 560 may determine a division ratio of the dual modulus prescaler 520 and may include a counter. For example, the division ratio of the dual modulus prescaler 520 is 2N when the control signal SCON has a low level and the division ratio of the dual modulus prescaler 520 is 2N−1 when the control signal SCON has a high level.
[0037] The frequency divider 500 shown in FIG. 3 operates as follows.
[0038] An output signal of a PLL circuit, e.g., a signal SOUT output from a VCO is divided by the frequency divider 500 . The dual modulus prescaler 520 divides the frequency of the output signal SOUT by a division ratio 2N when the control signal SCON has a low level or the dual modulus prescaler 520 divides the frequency of the output signal SOUT by a division ratio 2N−1 when the control signal SCON has a high level.
[0039] The 1/(2N) or 1/(2N−1) prescaled output signal PDIV from the dual modulus prescaler 520 is scaled by a predetermined division ratio M by the fixed division ratio scaler 540 .
[0040] FIG. 4 is a circuit diagram of an embodiment of a dual modulus prescaler 520 shown in the frequency divider of FIG. 3 . Referring to FIG. 4 , a dual modulus prescaler 520 includes a frequency division unit 521 and a frequency division ratio controller 526 . The frequency division unit 521 may include a plurality N of D flip-flops, where N is a natural number larger than or equal to 2. For example, the frequency division unit 521 may include four D flip-flops 522 , 523 , 524 and 525 as shown in FIG. 4 . A VCO output signal SOUT is inputted to each of the clock terminals CK of the D flip-flops 522 to 525 . The signal SOUT, therefore, clocks the D flip-flops 522 to 525 .
[0041] An output signal D 01 of the first D flip-flop 522 is applied to an input terminal D of the second D flip-flop 523 , an output signal D 02 of the second D flip-flop 523 is applied to an input terminal D of the third D flip-flop 524 and an output signal D 03 of the third D flip-flop 524 , is applied to an input terminal D of the fourth D flip-flop 525 .
[0042] The output signal PDIV is output from the terminal of the fourth D flip-flop 525 of the frequency division unit 521 is outputted from an output terminal Q of the fourth D flip-flop 525 . An output signal from an inverted output terminal QB of the fourth D flip-flop 525 is fed back into the input terminal D of the first D flip-flop 522 .
[0043] The frequency division ratio controller 526 includes serially connected NMOS transistors MN 3 and MN 4 . The NMOS transistor MN 3 includes a drain coupled to the output terminal Q of the first D flip-flop 522 and a gate coupled to receive the control signal SCON from the control circuit 560 ( FIG. 3 ). The NMOS transistor MN 4 includes a drain coupled to a source of the NMOS transistor MN 3 , a gate coupled to receive the PDIV signal from the output terminal Q of the fourth D flip-flop 525 , and a source coupled to a ground voltage GND.
[0044] Unlike the modulus prescaler shown in FIG. 2 that operates at a speed determined by the delay time of the NAND gate 21 and the NMOS transistors MN 1 and MN 2 , the dual modulus prescaler shown in FIG. 3 operates at a higher speed largely determined by the transistor MN 4 .
[0045] The dual modulus prescaler shown in FIG. 3 employs two cascade connected transistors MN 3 and MN 4 rather than a logic circuit, e.g., the NAND gate 21 shown in FIG. 2 , to speed up the operation.
[0046] FIG. 5 is a timing diagram of the dual modulus prescaler shown in FIG. 4 when a control signal SCON has a low level. FIG. 6 is a timing diagram of the dual modulus prescaler shown in FIG. 4 when a control signal SCON has a high level.
[0047] When the control signal SCON has a logic level ‘0’, an exemplary operation of the dual modulus prescaler of FIG. 4 is as follows. When the control signal SCON has a logic level ‘0’, the NMOS transistor MN 3 is off. The frequency of the output signal PDIV of the dual modulus prescaler 520 is equal to ⅛ of the frequency of the VCO output signal SOUT as shown in the timing diagram of FIG. 5 . That is, when the control signal SCON has a logic level ‘0’, the frequency of the output signal of a dual modulus prescaler 520 having a frequency division unit with N D flip-flops is equal to 1/(2N) of the frequency of the VCO output signal SOUT.
[0048] Referring to FIG. 5 , the output signal D 01 of the first D flip-flop 522 changes from ‘0’ to ‘1’ at the first rising edge of the VCO output signal SOUT.
[0049] The output signal D 01 is continuously maintained at ‘1’ during the first four periods of the VCO output signal SOUT, and the output signal D 01 changes from ‘1’ to ‘0’ after the first four periods of the VCO output signal SOUT. The output signal D 01 is continuously maintained at ‘0’ during the second four periods of the VCO output signal SOUT, and the output signal D 01 changes from ‘0’ from ‘1’ at the 9th rising edge of the VCO output signal SOUT. And so on.
[0050] The output signal D 02 of the second D flip-flop 523 changes at the second rising edge of the VCO output signal SOUT after the output signal D 01 changes at the first rising edge of the VCO output signal SOUT.
[0051] The output signal D 03 of the third D flip-flop 524 changes at the third rising edge of the VCO output signal SOUT after the output signal D 02 changes at the second rising edge of the VCO output signal SOUT.
[0052] As a result, one loop period of the output signal PDIV of the fourth D-flip flop 525 is eight times a period (or a cycle) of the VCO output signal SOUT. That is, the frequency of the output signal PDIV of the dual modulus prescaler 520 is equal to ⅛ of the frequency of the VCO output signal SOUT.
[0053] As shown in FIG. 4 , each of the D flip-flops shifts latched data to next stage D flip-flop on every SOUT clock cycle. Thus, output data D 00 , D 01 , D 03 , PDIV of each of the D flip-flops changes at a sequence ‘0000’ ‘1000’, ‘1100’, ‘1110’, ‘1111’, ‘0111’, ‘0011’, ‘0001’, ‘0000’. Since one loop period corresponds to eight clock cycles of the VCO output signal SOUT, the frequency of the output signal PDIV is equal to ⅛ of the frequency of the VCO output signal SOUT.
[0054] When the control signal has a logic level ‘1’, an operation of the dual modulus prescaler of FIG. 4 is as follows. When the control signal SCON is ‘1’, the NMOS transistor MN 3 is on. The frequency of the output signal PDIV=D 04 of the dual modulus prescaler 520 shown in FIG. 4 is equal to 1/7 of the frequency of the VCO output signal SOUT as shown in the timing diagram of FIG. 6 . That is, the frequency of the output signal of a dual modulus prescaler 520 having a frequency division unit with N D flip-flops is equal to 1/(2N−1) of the frequency of the VCO output signal SOUT.
[0055] Referring to FIG. 6 , the output signal D 01 of the first D flip-flop 522 changes from ‘0’ to ‘1’ at the first rising edge of the VCO output signal SOUT.
[0056] The output signal D 01 is continuously maintained at ‘1’ during the first three periods of the VCO output signal SOUT, and the output signal D 01 changes from ‘1’ to ‘0’ after the first three periods of the VCO output signal SOUT.
[0057] When the control signal SCON has a logic level ‘1’, the output signal D 01 of the first D flip-flop 522 has a different transition point compared with the output signal D 01 when the control signal SCON is ‘0’ as shown in FIG. 5 .
[0058] The output signal D 01 is continuously maintained at ‘0’ during the second four periods of the VCO output signal SOUT, and the output signal D 01 changes from ‘0’ to ‘1’ at the 8th rising edge of the VCO output signal SOUT.
[0059] The output signal D 02 of the second D flip-flop 523 changes at the second rising edge of the VCO output signal SOUT after the output signal D 01 of the first D flip-flop 522 changes at the first rising edge of the VCO output signal SOUT.
[0060] The output signal D 03 of the third D flip-flop 524 changes at the third rising edge of the VCO output signal SOUT after the output signal D 02 of the second D flip-flop 523 changes at the second rising edge of the VCO output signal SOUT.
[0061] As a result, one loop period of the output signal PDIV of the fourth D flip-flop 525 is seven times of the period of the VCO output signal SOUT. That is, the frequency of the output signal PDIV of the dual modulus prescaler 520 is equal to 1/7 of the frequency of the VCO output signal SOUT.
[0062] The operation of prescaler 520 shown in FIG. 6 is different from the operation of the prescaler 520 shown in FIG. 5 in that the output terminal of the first D flip-flop 522 is pulled down to a logic level ‘0’ when the output terminal of the last D flip-flop 525 changes from ‘0’ to ‘1’ because the transistor MN 4 is on due to the high level of the output terminal of the last D flip-flop 525 . Thus, the output data D 00 , D 01 , D 03 , PDIV of the D flip-flops 522 , 523 , 524 and 525 changes at a sequence of ‘0000’ ‘1000’, ‘1100’, ‘1110’, ‘0111’, ‘0011’, ‘0001’, ‘0000’. Namely, the output data D 00 , D 01 , D 03 , PDIV of the D flip-flops 522 , 523 , 524 and 525 changes from ‘0111’ to ‘1110’ without passing through ‘1111’. Since one loop period corresponds to seven clock cycles of the VCO output signal SOUT, the frequency of the output signal PDIV is equal to 1/7 of the frequency of the VCO output signal SOUT.
[0063] The gate of the NMOS transistor MN 3 included in the frequency division ratio controller 526 receives the control signal SCON. And the gate of the NMOS transistor MN 4 receives the output signal PDIV of the dual modulus prescaler 520 . Alternatively, the gate of the NMOS transistor MN 4 may receive the control signal SCON. And the gate of the NMOS transistor MN 3 may receive the output signal PDIV of the dual modulus prescaler 520 .
[0064] FIG. 7 is a circuit diagram of an embodiment of a dual modulus prescaler included in the frequency divider of FIG. 3 .
[0065] A frequency division ratio controller 526 illustrated in FIG. 7 differs from the frequency division ratio controller 526 illustrated in FIG. 4 in that frequency division ratio controller 526 illustrated in FIG. 7 includes PMOS transistors rather than NMOS transistors.
[0066] Referring to FIG. 7 , the frequency division ratio controller 526 includes serially connected PMOS transistors MP 3 and MP 4 .
[0067] The PMOS transistor MP 4 has a drain coupled to an output terminal Q of a first D flip-flop 522 and a gate for receiving a control signal SCON.
[0068] The PMOS transistor MP 3 has a drain coupled to a source of the PMOS transistor MP 4 , a gate coupled to an output terminal Q of the fourth D flip-flop 525 and a source coupled to a power supply voltage VDD.
[0069] When the control signal SCON is ‘0’, the PMOS transistor MP 4 is on. When the control signal SCON is ‘1’, the PMOS transistor MP 4 is off.
[0070] An operation of the dual modulus prescaler illustrated in FIG. 7 is similar to that described earlier relative to the prescaler 520 shown in FIG. 4 , and will not be described further.
[0071] The dual modulus prescaler shown in FIG. 7 has a time delay due to the transistor MP 3 . This time delay is an improvement to the time delay associated with other known dual modulus prescalers that include delays associated with the NAND gate 21 and the NMOS transistors MN 1 and MN 2 .
[0072] The dual modulus prescaler according to an example embodiment of the present invention employs two serially connected transistors MP 3 and MP 4 rather than a logic circuit.
[0073] Accordingly, the frequency divider having the dual modulus prescaler according to the embodiments described are suitable for applying to a PLL system that operates at a high frequency such as a system running between 1 to 10 GHz.
[0074] While the example embodiments and their advantages have been described in detail, it should be understood that various changes, substitutions, and alterations may be made without departing from the scope and spirit of the claims.
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We describe a dual modulus prescaler that may be used in a high frequency PLL. The prescaler comprises a frequency division unit to generate a prescaled signal by dividing a frequency of an input signal by a division ratio and a frequency division ratio controller to determine the division ratio responsive to a count signal and the prescaled signal. The frequency division unit divides a frequency of an input signal by a division ratio of 2N or (2N−1) to output a prescaled signal. The frequency division ratio controller determines a division ratio responsive to a count signal and the prescaled signal.
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CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims foreign priority benefits under 35 U.S.C. §119(a)-(d) to Chinese patent application number CN 201610041543.7, filed Jan. 21, 2016, which is incorporated by reference in its entirety.
TECHNICAL FIELD
[0002] The present application belongs to the technical field of the petroleum exploration, and more particularly, to a coring structure in the technical field of the petroleum exploration.
BACKGROUND
[0003] In existing coring device, the electric motor and the speed reducer are two separate elements, and the drill bit is connected with the speed reducer through a flexible shaft. This structure has lower transmission efficiency, and the flexible shaft is easy to break and bend, the maintenance rate of the instrument is higher.
[0004] The stretching of the drill bit of the existing coring device is achieved by four hydraulic cylinders jacking the frame, the rotating and swinging of the drill bit are achieved by other hydraulic cylinder and control mechanism, its structure is complex and multiple power sources are needed.
SUMMARY
[0005] One object of the present disclosure is to provide a sidewall coring structure that has higher transmission efficiency and improved the drill bit propulsion.
[0006] To achieve the above object of the disclosure, the present application provides the following technical solution.
[0007] A sidewall coring structure configured to be directly driven by an electric motor, comprising a drill bit, an electric motor and a speed reducer, wherein the electric motor and the speed reducer are an integrated structure and the drill bit is directly connected to an output of the speed reducer.
[0008] Alternatively, the housings of the electric motor and the speed reducer are separable, both of which are sealedly and fixedly connected and an output shaft of the electric motor is as a fixed shaft of an input gear of the speed reducer.
[0009] Alternatively, an output port of the electric motor has a wire protection device that can rotate with the rotation of the drill bit.
[0010] Alternatively, the wire protection device is turnably and sealedly connected to the electric motor, and a wire of the electric motor is fixed by the wire protection device and rotates therewith.
[0011] Alternatively, the wire protection device comprises two parts: a main structure and an auxiliary structure, and a wire groove for fixing the wire of the electric motor is formed within the main structure.
[0012] The above technical solution has the following beneficial technical effects compared to prior art.
[0013] The transmission efficiency of a coring mechanism which is directly driven by the speed reducer is greatly improved; meanwhile, the coring structure is more simplified with improved reliability, easier maintenance and reduced maintenance cost.
[0014] Compared to the separated structure of the electric motor and speed reducer in existing coring structure, it is better adapted to the work environment of the high temperature and pressure of the coring structure, and the integrated electric motor and speed reducer makes the volume of the drive device of drill bit smaller and is conductive to the miniaturization of the coring device.
[0015] The configuration of an electric motor wire follower device provides safeguard for the drill bit directly driven by the speed reducer and the electric motor, and also ensures a normal operation of the electric motor during stretching and turning motions of the drill bit.
[0016] Another object of the present disclosure is to provide a sidewall coring structure that has higher transmission efficiency and the motion control mechanism of the drill bit is more simple and effective.
[0017] In order to achieve above object of the disclosure, the present application provides the following technical solution.
[0018] A sidewall coring structure directly driven by an electric motor comprising a drill bit, a drive device of drill bit and a frame, the drill bit is connected to an output of the drive device of drill bit, wherein further comprises a motion control mechanism of drill bit, the motion control mechanism of drill bit is accommodated within the frame and the drive device of drill bit is accommodated within the motion control mechanism of drill bit, the motion control mechanism of drill bit drives the drill bit to achieve the stretching and turning motions.
[0019] Alternatively, the motion control mechanism of drill bit comprises an auxiliary bracket, a group of parallel sliding plates and hydraulic oil cylinders, both the auxiliary bracket and the drive device of drill bit are accommodated in a space formed after the fixation of the sliding plates, the auxiliary bracket and the drive device of drill bit are movably connected, the sliding plates horizontally slide along an axial direction of the coring structure under the pushing from the hydraulic oil cylinders and drive the drive device of drill bit to stretch and turn.
[0020] Alternatively, the auxiliary bracket and the drive device of drill bit are slidably connected by a connecting plate, and the auxiliary bracket limits the horizontal motion of the drive device of drill bit along the axial direction of the coring structure as well as the clockwise turning motion with respect to the auxiliary bracket.
[0021] Alternatively, the connecting plate is slidably connected to the sliding plate and is turnably connected to the drive device of drill bit.
[0022] Alternatively, a first sliding shaft and a rotating shaft hole are provided on the connecting plate, and a second sliding shaft and a rotating shaft are provided on the drive device of drill bit; a first inclined chute and a second inclined chute are formed on the sliding plate, the first sliding shaft is sleeved within the first inclined chute, and the second sliding shaft is sleeved within the second inclined chute; and the rotating shaft is sleeved within the rotating shaft hole.
[0023] Alternatively, a horizontal chute is provided at an end of the first inclined chute, the first inclined chute is in continuous communication with the horizontal chute; and an arc chute is provided within the second inclined chute, and the second inclined chute is in continuous communication with the arc chute.
[0024] Alternatively, a limit groove is provided at an end of the connecting plate, in the meantime, the second sliding shaft is sleeved within the limit groove, and the limit groove limits a clockwise rotation of the drive device of drill bit driven by the second sliding shaft.
[0025] Alternatively, the auxiliary bracket has a turning groove that accommodates the drive device of drill bit driving the drill bit to turn 90 degrees counterclockwise.
[0026] Preferably, there are two hydraulic oil cylinders.
[0027] Alternatively, the drive device of drill bit is an integrated structure that includes the electric motor and the speed reducer, and the drill bit is connected to the output of the speed reducer.
[0028] Alternatively, the housings of the electric motor and the speed reducer are separable, both of which are sealedly and fixedly connected and an output shaft of the electric motor is as a fixed shaft of an input gear of the speed reducer.
[0029] Alternatively, the second sliding shaft and the rotating shaft are formed in the housing of the speed reducer and the rotating shaft is located at a center of the housing of the speed reducer; the second sliding shaft is eccentrically provided with respect to the rotating shaft.
[0030] Alternatively, the output port of the electric motor has a wire protection device that can rotate with the rotation of drill bit.
[0031] The above technical solution brings the following beneficial technical effects compared to the prior art.
[0032] The stretching and turning motions of the drill bit of this application can be achieved by a kit of drill bit control mechanism, the control mechanism of the coring structure is more simplified and more directly and effectively to control the motions of the drill bit with respect to the existing two kit of mechanisms for respectively achieving stretching and turning.
[0033] The stretching and turning control and the pushing force control of the drill bit in the coring structure of the present application can be fully achieved by only two hydraulic oil cylinders; with respect to a plurality of hydraulic oil cylinders required in the prior art, the present application has a simpler structure and a higher utilization rate of power.
BRIEF DESCRIPTION OF THE DRAWINGS
[0034] FIG. 1 is a perspective view of the integrated structure of the drill bit, the speed reducer and the electric motor;
[0035] FIG. 2 is a sectional view of the integrated structure of the drill bit, the speed reducer and the electric motor;
[0036] FIG. 3 is a front view of the integrated structure of the drill bit, the speed reducer and the electric motor;
[0037] FIG. 4 is a sectional view along A-A in FIG. 3 ;
[0038] FIG. 5 is a schematic diagram of the drilling process by the drill bit with the body removed;
[0039] FIG. 6 is a structure schematic diagram of the auxiliary bracket;
[0040] FIG. 7 is a schematic diagram of the connection of the speed reducer and the auxiliary bracket after removing the body, the sliding plates and the connecting plate;
[0041] FIG. 8 is a schematic diagram of the connection of the sliding plate and a long fixed block;
[0042] FIG. 9 is a structure schematic diagram after installing the body;
[0043] FIG. 10 is a schematic diagram of the drill bit turning with the sliding plates removed; and
[0044] FIG. 11 is a schematic diagram of the drill bit turning without the sliding plates removed.
REFERENCE SIGNS
[0000]
1 —an electric motor; 101 —a rotor shaft of electric motor; 102 —a housing;
2 —a speed reducer; 201 —an input gear; 202 —an output shaft; 203 —a housing; 204 —a chute;
3 —a drill bit; 4 —a rotating shaft; 5 —a second sliding shaft;
6 —a wire follower protection device; 601 —a main structure; 602 —a wire groove; 603 —a seal ring; 604 —an auxiliary component;
7 —wire; 8 —screw;
9 —a sliding plate; 901 —a first inclined chute; 902 —an arc chute; 903 —a horizontal chute; 904 —a slider; 905 —a second inclined chute;
10 —a hydraulic cylinder piston; 11 —a long fixed block; 1101 —a horizontal chute;
12 —an auxiliary bracket; 1201 —a vertical chute; 1202 —a limit face; 1203 —a turning groove; 1204 —a connection groove;
13 —a body; 14 —a short fixed block;
15 —a connecting plate; 1501 —a sliding block; 1502 —a limit groove; 1503 —a first sliding shaft; and
16 —a connecting block.
DETAILED DESCRIPTION
[0056] As required, detailed embodiments are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary and that various and alternative forms may be employed. The figures are not necessarily to scale. Some features may be exaggerated or minimized to show details of particular components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art.
[0057] In order to make the disclosure objects, technical solutions and beneficial effects of the disclosure clearer, the embodiments of the present disclosure will be described in detail below in conjunction with accompanying drawings. It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other randomly without conflict.
[0058] FIG. 1 , FIG. 2 and FIG. 3 show a perspective view, a sectional view and a front view of the integrated structure portion of a drill bit, a speed reducer and an electric motor of the sidewall coring structure directly driven by an electric motor in the embodiment. FIG. 1 shows the connection relations of an electric motor 1 , a speed reducer 2 , a drill bit 3 and an electric motor wire follower protection device 6 (i.e., a wire protection device), wherein the electric motor 1 and the speed reducer 2 are an integrated structure, the drill bit 3 is directly connected to the speed reducer 2 , the electric motor wire follower protection device is rotatably connected to a tail of the electric motor 1 .
[0059] FIGS. 2 and 3 show the connection relations of the interiors and the housings of the electric motor 1 , the speed reducer 2 and the drill bit 3 , a housing 102 of the electric motor 1 and a housing 203 of the speed reducer 2 are separable, and both are fixed by screws 8 ; preferably, both are sealedly and fixedly connected. The drill bit 3 is directly connected to an output shaft 202 of the speed reducer 2 and a rotor shaft 101 of the electric motor is as a fixed shaft of an input gear 201 of the speed reducer 2 . This structure simplifies the connection between the drill bit 3 and the speed reducer 2 (the connection is simplified from the previous connection by a flexible shaft to a direct connection), and improves the power transmission efficiency from the original 35% to 80%.
[0060] FIG. 3 shows a housing structure of the speed reducer 2 , and a rotating shaft 4 and a second slide shaft 5 are symmetrically provided on both sides of the housing of the speed reducer 2 ; wherein the rotating shaft 4 is located at a center position of a side of the housing of the speed reducer 2 and the second sliding shaft 5 is eccentrically provided relative to the rotating shaft 4 . FIG. 3 also shows a chute 204 provided on a prism portion on each of both sides of a front end of the speed reducer 2 for matching a position of a prism on an end face of the auxiliary bracket.
[0061] Referring to FIG. 3 and FIG. 4 , FIG. 4 shows a connection relation between the electric motor wire follower protection device 6 and the electric motor 1 and an internal structure of the follower protection device. A shaft hole is provided at a tail of the electric motor 1 and a rotating shaft is provided at an end of the electric motor wire follower protection device 6 , both of which form a rotatable connection relation. The electric motor wire follower protection device 6 consists of a main structure 601 and an auxiliary component 604 , when assembled, the main structure 601 is sleeved in the shaft hole of the tail of the electric motor 1 , followed by fitting an auxiliary component 604 , both of which are secured to an integral whole by screws, and the main structure 601 is sealedly connected to the housing of the electric motor 1 by seal rings 603 . The main structure 601 includes a rotating shaft portion and a main body portion, wherein the rotating shaft portion is hollow and the main body portion has a wire groove 602 for fixing the wire 7 of the electric motor; a tail of the main body portion has a hole for leading wire to extend out.
[0062] Referring to FIGS. 5 to 9 , wherein FIG. 5 is a schematic diagram of the drilling process of the drill bit with the body removed; FIG. 6 is a structure schematic diagram of an auxiliary bracket; FIG. 7 is a schematic diagram of the connection of the speed reducer and the auxiliary bracket after removing the body, the sliding plates and the connecting plate; FIG. 8 is a schematic diagram of the connection of the sliding plate and the long fixed block; FIG. 9 is a structure schematic diagram after installing the body; FIG. 5 shows a pair of sliding plates 9 in parallel, but it is not limited to provide a pair of sliding plates 9 , and multiple pairs may be provided as required. An end of each sliding plate 9 is fixedly connected to a hydraulic cylinder piston 10 , wherein a front end, a middle and a rear end of the sliding plate 9 are fixed to be a space with opening top and bottoms through the short fixed blocks ( FIG. 5 merely marks the short fixed block 14 at the front end, the short fixed blocks at the middle and the rear end are not showed in the figure because of being blocked); the electric motor 1 , the speed reducer 2 and the drill bit 3 are connected to an integrated structure accommodated within the space. A first inclined chute 901 and a second inclined chute 905 and a slider 904 that is matched with a long fixed block 11 are provided at an outside of the sliding plate 9 (see FIG. 8 ), the slider 904 is matched with a chute on the long fixed block 11 and the long fixed block 11 is fixedly connected with a body 13 (see FIG. 9 ); under the action of the hydraulic cylinder piston 10 , the slide plate 9 horizontally moves along the long fixed block 11 . Meanwhile, the second sliding shaft 5 of the speed reducer 2 moves along the second inclined chute 905 , drives the integrated structure connected by the electric motor 1 , the speed reducer 2 and the drill bit 3 to perform vertical movement, to achieve stretching of the drill bit 3 ; a bottom of the second inclined chute 905 that is matched with the second sliding shaft 5 has an arc chute 902 , and a bottom of the first inclined chute 901 that is matched with a first sliding shaft 1503 exterior to the connecting plate has a horizontal chute 903 (see FIG. 11 ).
[0063] Referring to FIG. 6 and FIG. 7 , wherein FIG. 6 is a perspective view of an auxiliary bracket 12 , FIG. 7 is a schematic diagram of the connection of the speed reducer and the auxiliary bracket after removing the body, the sliding plates and the connecting plate; FIG. 6 shows that the auxiliary bracket 12 is an integrally molded hollow profiled cuboid, a through (not interrupted) vertical chute 1201 is provided on one side thereof, the tops of both the side provided with the vertical chute 1201 and its opposite side are provided with a connection groove 1204 for receiving a connecting block 16 connected to the body, the connecting block 16 and the auxiliary bracket 12 are connected by screws. A top of a surface adjacent to the vertical chute 1201 is a vertical face which is as a limit face 1202 of stretching movement of the drill bit 3 and at the same time this face limits the drill bit 3 horizontally sliding. A turning groove 1203 is formed because of the internal reduction in the bottom of the vertical face for holding the turned drill bit (see FIG. 10 ). FIG. 7 shows that a connecting plate 15 is connected with the auxiliary bracket 12 and the speed reducer 2 ; the connecting plate 15 is a rectangular flat plate, one end thereof (at a side connecting with the auxiliary bracket 12 ) is provided with a sliding block 1501 , the sliding block 1501 is matching with the vertical chute 1201 of the auxiliary bracket 12 , and an outer side corresponding to the position of the sliding block 1501 has a first sliding shaft 1503 , the other end of the connecting plate 15 projects outwardly to form a projecting portion, a shaft hole is provided on the projecting portion to cooperate with a rotating shaft 4 of the speed reducer 2 , a limit groove 1502 is formed between the projecting portion and the connecting plate body for restricting the clockwise rotation of the integrated structure of the drill bit, the speed reducer and the electric motor, the second sliding shaft 5 of the speed reducer 2 is located within the limit groove 1502 . In addition, because the bottom of the vertical chute 1201 of the auxiliary bracket 12 is stepwise graduated within the chute, when the sliding block 1501 of the connecting plate 15 slid to the bottom of the vertical chute 1201 , a self-locking can form.
[0064] Referring to FIG. 10 and FIG. 11 , FIG. 10 and FIG. 11 show a relative positional relation between the various members during turning of the drill bit of the coring structure. When the drilling operation is completed, the drill bit is retracted to the body; at this time, the second sliding shaft 5 of the speed reducer 2 and the first sliding shaft 1503 of the outside of the connecting plate simultaneously respectively reach the bottom of the second inclined chute 905 and the bottom of the first inclined chute 901 ; under continuous pressure, while the second sliding shaft 5 moves along the arc chute 902 , the integrated structure of the electric motor 1 , the speed reducer 2 and the drill bit 3 rotates around the rotating shaft 4 counterclockwise, the second sliding shaft 5 roll out from the limit groove 1502 ; when the drill bit turns 90 degrees, the drill bit 3 fully enters into the turning groove 1203 of the auxiliary bracket 12 . The first sliding shaft 1503 moves along the horizontal chute 903 while the second sliding shaft 5 moves.
[0065] In specific application, on the basis of the above-mentioned technical solutions, the drilling depth of the drill bit can be determined by providing one or more sensors on the hydraulic cylinder piston and by testing the movement distance of the hydraulic cylinder piston.
[0066] In specific application, the electric motor may adopt a brushless DC motor; and the speed reducer may adopt a reducer driven by helical gears.
[0067] The sidewall coring structure directly driven by an electric motor of the present embodiments improves power mechanism of the drill bit from the existing connection of the electric motor and the speed reducer and the drill bit being connected with the speed reducer through the flexible shaft to transmit power to an integrated structure of the electric motor and the speed reducer to drive the drill bit directly; the stretching and turning of the drill bit are achieved by providing the auxiliary bracket, the sliding plates and a set of hydraulic oil cylinders, thus the stretching and turning of the drill bit are achieved using one control mechanism. It is easily understood that in another embodiment, it may merely use the power mechanism for drilling of this embodiment to improve efficiency. While in another embodiment, it merely uses the present embodiment to achieve the control mechanism of the drill bit; at this time, the power mechanism of the drill bit does not need to use an integrated structure of the electric motor and the speed reducer, and may also use a hydraulic motor.
[0068] While exemplary embodiments are described above, it is not intended that these embodiments describe all possible forms according to the disclosure. The words used in the specification are words of description rather than limitation, and it is understood that various changes may be made without departing from the spirit and scope of the disclosure. Additionally, the features of various implementing embodiments may be combined to form further embodiments according to the disclosure.
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The present application provides a sidewall coring structure directly driven by an electric motor comprising a drill bit, an electric motor and a speed reducer, the electric motor and the speed reducer are an integrated structure and the drill bit is directly connected to an output of the speed reducer. The coring structure directly drives the drill bit through an integrated structure of the speed reducer and the electric motor; its transmission efficiency is greatly improved, meanwhile the coring structure is more simplified, with improved reliability, easier maintenance and reduced maintenance cost.
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BACKGROUND OF THE INVENTION
This invention relates to a tape run speed-changing circuit adapted to be used with a multispeed type tape recorder having cue and review functions.
A tape recorder used in place of a written memorandum offers great advantages, if provided with cue and review functions. The term "cue" denotes an operator's action of effecting the fast forward (FF) mode of a magnetic tape, while listening to the sounds produced from a tape. The term "review" represents an operator'action of carrying out the rewind (RW) mode of the magnetic tape, while listening to the sounds produced from the tape. The cue and review modes of the tape recorder are used to check the contents of data recorded in the tape. Since the operator carries out the cue and review modes to quickly check the contents of the tape while listening to said contents reproduced from the tape, the tape should naturally run at a proper speed. In other words, if the tape travels too slowly, then the check of the recorded data consumes a considerably long time. Conversely where the tape run is unduly fast, it is impossible for the operator to distinctly hear the reproduced sounds. The speed at which the tape runs for the cue or review mode should be properly changed in accordance with the speed at which the tape originally travelled for the recording mode, for instance. Now let it be assumed that data was recorded on a tape, while it was run at a speed of 2.4 cm/s, and there is provided a tape recorder which is so designed as to cause a tape to travel for the cue or review mode at a speed conforming to the above-mentioned recording speed of 2.4 cm/s. Where it is attempted to check data recorded in a tape at a tape run speed of 1.2 cm/s by means of the aforesaid fast tape run type tape recorder at the cue or review mode, then the tape run is so fast that the operator has considerable difficulties in hearing sounds reproduced from said 1.2 cm/s recorded type tape. Conversely where it is attempted to check sounds recorded in a tape at a tape run speed of 2.4 cm/s by means of a tape recorder which is designed to cause a tape to travel for the cue or review mode at a speed of 1.2 cm/s, then recorded sounds are checked with an exceedingly low efficiency.
SUMMARY OF THE INVENTION
This invention has been accomplished in view of the above-mentioned circumstances, and is intended to provide a tape run speed-changing circuit which enables a tape run speed for the cue or review mode to be changed in accordance with the speed at which a tape originally travelled for the recording or playback mode by a tape recorder.
To this end, the present invention provides a tape run speed-changing circuit which comprises a means for changing a tape run speed for the cue or review mode in accordance with the original tape run speed for the recording or playback mode. Specifically, when an optimum tape run speed for the cue or review mode is chosen to be 4.8 cm/s, with respect to a tape which was run at a speed of 1.2 cm/s for recording, then the tape run speed-changing circuit of this invention comprises a means for changing a tape run speed for the cue or review mode to 9.5 cm/s with respect to a tape which travelled at a speed of 2.4 cm/s for recording.
Provision of such tape run speed-changing circuit always enables a tape to run at a proper speed for the cue or review mode with respect to a tape in which data was recorded at a tape run speed of 1.2 or 2.4 cm/s.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows the arrangement of a tape run speed-changing circuit embodying this invention;
FIG. 2 indicates the arrangement of a modification of said circuit in which the mechanical switch 16 of FIG. 1 is replaced by a semiconductor switch; and
FIG. 3 schematically shows a circuit for continuously changing a tape run speed for the recording or playback mode (hereinafter referred to as "a tape transport speed") and a tape run speed for the cue and review mode (hereinafter referred to as "a tape feed speed"), with the ratio between both speeds fixed.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Description is now given with reference to the accompanying drawings of a tape run speed-changing circuit embodying this invention. The same or similar parts are denoted by the same numerals throughout the drawings, description thereof being omitted. The parts represented by the same numerals may be exchanged for each other directly or with minor modification which is easy for one skilled in the art.
Referring to FIG. 1, the positive pole of a power source 10 is connected to the collector of a speed-control NPN transistor 14 through a first switch 12. The negative pole of the power source 10 is grounded. The positive pole of the power source 10 is connected to the first and second contacts of a first tape run speed-changing switch 16 1 through the corresponding resistors R10, R12. The contactor of the tape run speed-changing switch 16 1 is connected to the positive pole of the power source 10 through a second switch 18. The contactor of said tape run speed-changing switch 16 1 is also connected to one end of a motor 22 through a third switch 20 and resistor R14. The other end of the motor 22 is grounded.
Said one end of the motor 22 is connected to the emitter of the transistor 14 through a diode 23. The base of the transistor 14 is connected to its own collector through a resistor R16. The base of the transistor 14 is further connected to the output terminal of an amplifier 24. The inverted input terminal of the amplifier 24 is connected to one end of a frequency generator 22 1 through a rectifier 26. The other end of the frequency generator 22 1 is grounded. Said frequency generator 22 1 is coupled to the motor 22. In other words, the frequency generator 22 1 produces an AC voltage eg proportional to the running speed of the motor 22. The AC voltage eg is rectified by a rectifier 26 to be converted into a D.C. voltage Eg conforming to the running speed of the motor 22.
A noninverted input terminal of the amplifier 24 is connected to the contactor of a second tape run speed-changing switch 16 2 . The first and second contacts of said second tape run speed-changing switch 16 2 are respectively connected to the positive poles of a first referential voltage ES10 and second referential voltage ES12. The negative poles of said first and second referential voltages ES10, ES12 are grounded. The switches 16 1 , 16 2 jointly constitute a 2-gangs 2-contacts tape run speed-changing switch system 16.
The foregoing description refers to the arrangement of a motor included in a tape transport system (not shown) and motor-driving electric circuit. FIG. 1 indicates a record-playback amplifier system 28. This amplifier system 28 is supplied with power from the power source 10 through the first switch 12. The amplifier system 28 is connected to a record-playback head 30 and loudspeaker 32. The record-playback head 30 is used for said purpose, and the amplifier system 28 is actuated as a playback amplifier.
The circuit arranged as shown in FIG. 1 is operated as follows. At the recording or playback mode, the first switch 12 is rendered conducting, while the third switch 20 is thrown out of operation. At this time, the record-playback amplifier system 28 is actuated, and the motor 22 is supplied with power from the emitter of the transistor 14. Now let it be assumed that the switch 16 is operated through the first contact, and the motor 22 is driven at a lower speed than prescribed. In this case the frequency generator 22 1 sends forth a small output. As a result, the equation of Eg<ES10 results. Thus, the amplifier 24 has an increased output terminal potential, causing the motor 22 to be impressed with a higher voltage Em. The more increased the voltage Em, the higher the running speed of the motor 22, and consequently the more elevated the voltage Eg. In the case of Eg>ES10, an output voltage from the amplifier 24 drops. As a result, the voltage Em falls to reduce the running speed of the motor 22. Eventually, the running speed of the motor 22 is stabilized at Eg=ES10, that is, at the prescribed level. The elements 14, 22, 24, 26, R16, ES10 and ES12 collectively constitute a motor servo circuit 27. When the switch 16 is operated through the second contact, then the motor 22 is driven at a speed expressed as Eg=ES12. When a tape recorder is a 2-speeds type in which recording and playback can be carried out at tape transport speeds of 1.2 and 2.4 cm/s, then the voltage ES10 is made to correspond to the tape transport speed of 1.2 cm/s and the voltage ES12 is made to conform to the tape transport speed of 2.4 cm/s.
At the fast forward or rewind mode, the switch 12 is rendered nonconducting, and the switches 18, 20 are actuated. At this time, the motor 22 is supplied with power from the power source 10 through the switches 18, 20 and resistor R14. At this time, the motor servo circuit 27 and record-playback amplifier system 28 are not supplied with power, but are thrown out of operation. In other words, the motor 22 is driven at a high speed substantially proportional to the magnitude of the voltage Em. Therefore, the loudspeaker 32 does not produce sounds. A tape run at the FF or REW mode can be controlled by the resistor R14.
At the cue or review mode, the switches 12, 20 are rendered conducting and the switch 18 is thrown out of operation. Where the switch 16 is operated through the first contact, then the motor 22 is supplied with power from the power source 10 through the resistors R10, R14. At this time, the motor 22 is driven at a speed several times higher than a tape run speed of 1.2 cm/s, that is, a speed of, for example, 3.6 to 4.8 cm/s. The rotating speed of the motor 22 is controlled by changing, for example, the resistance of the resistor R10. At this time the equation Eg>ES10 results, leading to a decline in the potential of the output terminal of the amplifier 24. Thus, the diode 23 is biased backward and cut off, giving rise to the breakage of a servo loop. Therefore, even when the switch 12 is rendered conducting, the motor servo circuit 27 is not actuated. At this time, however, the amplifier system 28 is supplied with power. At the cue or review mode, the record-playback head 30 slidably touches a recorded tape (not shown), thereby setting the amplifier system 28 for the playback mode. In other words, the cue or review mode is carried out at a speed several times higher than a tape run speed of, for example, 1.2 cm/s for the recording mode.
When the switch 16 is operated through the second contact, then the motor 22 is supplied with power from the power source 10 through the resistors R12, R14. At this time, the motor 22 is driven at a speed several times higher than a tape run speed of 2.4 cm/s, that is, a speed of, for example, 7.2 to 9.5 cm/s. At this time, the rotating speed of the motor 22 is controlled by changing the resistance of the resistor R12.
As is apparent from the foregoing description, where the resistors R10, R12 have their resistances adjusted to a proper level, then the cue or review mode is carried out while a tape is run at a speed increased in the prescribed ratio over a tape run speed of 1.2 or 2.4 cm/s for the recording or playback mode. The change of a tape run speed for the cue or review mode in the specified ratio to that for the recording or playback mode is automatically carried out by the interlocking 2-gangs 2-contacts switch system 16. Therefore, it is unnecessary to change a tape run speed for the cue or playback mode each time in the specified ratio to the speed at which a tape was originally run for the recording or playback mode.
FIG. 2 shows the arrangement of a modification of the tape run speed-changing circuit of FIG. 1. In this modification, the switches 16 1 , 16 2 are replaced by electrical switch circuits. In other words, a logic signal having a level of "1" is supplied as a switching instruction to an input terminal 38 in the timing in which the tape run speed-changing switch system 16 is operated through the second contact instead of the first contact. At this time, an inverter 40 produces a signal having a logic level of "0". As a result, an NPN transistor Q16 13 is rendered conducting, and NPN transistors Q16 14 , Q16 2 are unactuated. Therefore, the motor 22 is supplied through the switch 20 with a second voltage higher than a first voltage defined by resistors R10 1 , R10 2 . The level of said second voltage is determined by resistors R12 1 , R12 2 . A voltage impressed on the noninverted input terminal of the amplifier 24 has its level raised from ES10 to ES12. This state arises from the fact that when the transistor Q16 2 is rendered nonconducting, an increase takes place in the ratio of (R16 22 +R16 23 )/(R16 21 +R16 22 +R16 23 ) of a voltage divider formed of resistors R16 21 , R16 22 , R16 23 . Conversely, where the transistor Q16 2 is rendered conducting, the dividing ratio of said voltage divider is reduced to R16 22 /(R16 21 +R16 22 ) defined by the resistors R16 21 , R16 22 . As a result, the noninverted input terminal of the amplifier 24 has its potential set at ES10 (ES10<ES12).
FIG. 3 shows the arrangement of a modification of FIGS. 1 and 2 indicating a circuit applied to effect a change between two prescribed tape run speeds for the recording or playback mode. FIG. 3 shows the arrangement by which it is continuously carried out to change a tape feed speed for the cue or review mode from 4.8 to 9.5 cm/s in the specified ratio to a tape transport speed of 1.2 to 2.4 cm/s for the recording or playback mode. The gang property of variable resistors VR16 1 , VR16 2 is so trimmed that a tape feed speed for the cue or review mode bears a specified ratio to that for the recording or playback mode, regardless of the position of a slider attached to each of said variable resistors VR16 1 , VR16 2 .
Although specific constructions have been illustrated and described herein, it is not intended that the invention be limited to the elements and constructions disclosed. One skilled in the art will recognize that other particular elements or sub-constructions may be used without departing from the scope and spirit of the invention. The motor servo circuit 27 for driving, for example, the motor 22 of FIG. 1 may be replaced by the ordinary electronic governor. The switches 12, 16, 18, 20 need not be of the mechanical type. Further, these switches 12, 16, 18, 20 may be formed of a combination of a transistor switch and semiconductor logic circuit like those shown in FIG. 2 or replaced by a relay circuit in part or in whole. A tape recorder to which the tape run speed-changing circuit of this invention is applied may be of the multi-speed type in which a tape may be run at three or more different speeds for the recording or playback mode.
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A tape run speed-changing circuit which comprises a motor driven at a speed conforming to any tape run speed for the recording or playback mode and also at a speed matching any tape run speed for the cue or review mode, a first tape run speed-changing device for specifying any tape run speed for the cue or review mode, and a second tape run speed-changing device which selects any tape run speed for the recording or playback mode and whose operation mode is changed over interlockingly with that of the first tape run speed-changing device. When the second tape run speed-changing means device specifies a first tape run speed for the recording or playback mode, then the first tape run speed-changing means device selects a first tape run speed for the cue or review mode; and when the second tape run speed-changing device specifies a second tape run speed for the recording or playback mode, then the first tape run speed-changing device selects a second tape run speed for the cue or review mode.
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BACKGROUND OF THE INVENTION
The present invention relates to the application of a deposit of material to a succession of discrete articles. More particularly, the present invention relates to a method and apparatus for depositing a droplet or an extended bead of thermoplastic or thermoset material onto the surface of a metal or plastic part. Once applied in accordance with the present invention, the flexible compressible bead extends above the surface of the part in order to create assembly resistance when the part is assembled into or over another part. This resistance serves to temporarily secure the location of the respective parts one to another prior to more permanent joining by welding, gluing or threaded torquing.
Many parts that are used in ultimate assembly in industries such as the automotive industry require some partial manual assembly prior to the ultimate incorporation of these parts into finished goods. For example, rear wheel drive axles of certain automobile manufacturers require the use of bolts coupled with lock washers as part of their assembly. Presently, employees must manually assemble the lock washers to the bolts in preparation for ultimate installation of the combined parts on an assembly line. As can be appreciated, the labor costs associated with manually assembling these lock washers to the bolts are rather significant. Furthermore, once the lock washers are assembled to the bolts there is no structure provided to keep them retained on the bolts pending final assembly. As a result, the washers often fall off in the box on the way to the final assembly line. If this occurs then the axles are assembled with washers missing and serious problems in the ultimate assembly can be created.
In another example, automobile companies have begun utilizing many brackets made from metal stampings which are attached to vehicles by several screws. The brackets and screws are currently shipped separately to the assembly plant under separate part numbers. Once they arrive at the installation facility, they must be coupled prior to installation. As a result, significant additional time and labor costs are incurred to combine the brackets and screws once they arrive at the installation plant. There is always the danger that one or more of the screws may fall out of the assembly prior to ultimate installation or through human error fail to initially be inserted in the appropriate place.
Prior attempts to meet these needs have proven inadequate. That is because the requirements for retaining the individual parts together as a single unit prior to assembly are multifaceted. In particular, it is required that any system that is used to accomplish this temporary retaining purpose cannot interfere with or alter the final assembly of the parts. For example, the structure used to accomplish the retaining function cannot alter the seating torques required to achieve a desired clamp load. Thus, there is a complicated balancing act between providing a retaining material which is tough enough to resist part disassembly, yet not change or interfere with the final assembly.
The prior art does not provide a completely adequate solution to this relatively recent assembly problem. For example, U.S. Pat. No. 4,851,175 to Wallace discloses a method of making O-rings by supplying a continuous stream of liquid hot melt material under the force of gravity alone onto a rotating spindle or directly upon the shank of the rotating fastener. This method, however, is capable of forming only a continuous O-ring around the outer circumference of the fastener and generally uses a heater such as a flame jet spaced from a falling filament of material to soften the deposit on each fastener to cause it to flow into a more conforming state as required such as a flatter wider band.
In addition, this prior art method contemplates a continuous filament of hot liquid material falling from a nozzle that is not capable of precisely locating a dot of such material on only a portion of the outer circumference of such fasteners. As a result, this method is only effective in producing O-rings that cover the entire 360° circumference of a portion of a fastener. Such an O-ring is usually intended to effect the final assembly of parts by acting as a seal or the like. Such an O-ring would be insufficient in many instances to provide a deposit of material that is tough enough to resist part disassembly, but does not interfere with or alter the final assembly of the parts. This prior art method likewise does not provide for discontinuous flow of material that only activates in the presence of a fastener.
It is likewise known to apply a patch of resilient thermoplastic material on a portion or all of the circumference of a selected portion of a fastener such as described in U.S. Pat. No. 3,787,222 to Duffy et al. The material deposited, however, acts not to temporarily retain two parts such as a bolt and washer in place, but rather to increase the resistance between two mating threaded parts in a final assembly and make them self locking so that they will have substantially increased resistance to uncoupling due to vibration and the like.
Another known method of applying thermoplastic material to substrates is disclosed, for example, in U.S. Pat. No. Re 33,766 to Duffy et al. This method applies a masking insulating or lubricating coating of teflon or similar material to all or a portion of the threads of the coating. However, the coating produced by this method does not extend far enough above the surface of the fastener or have sufficient retaining ability in order to serve as a retaining element for a second part. Both of these above described methods produce materials that tend to closely follow the contours of the threads of the fastener when applied and also interfere with the ultimate assembly of the parts.
It is apparent, therefore, that there is need to be able to form discrete deposits of material onto the surface of a part over 360° or less of the circumference of the part in order to form a deposit that resists part disassembly, but does not interfere with or alter the final assembly of the parts. The present invention further contemplates a method of forming more than one retaining element either of the same or different types on a single fastener or other discrete article and fasteners with such retaining elements applied thereto.
SUMMARY OF THE INVENTION
The present invention overcomes the deficiencies of the prior art by providing a method and apparatus for applying deposits of material around a portion or all of the circumference of discrete articles such as fasteners so that the material extends above the surface of the part to create assembly resistance serving to temporarily secure the location of the part one to another prior to more permanent joining by welding, gluing or threaded torquing of the entire assembly.
It is therefore an object of the present invention to provide a method and apparatus that accomplishes the above result in an effective and cost efficient manner.
It is another object of the present invention to provide the method and apparatus of providing a discrete deposit of retaining material on metal or plastic parts such as fasteners.
Yet another object of the present invention is to provide a flexible compressible deposit of material that projects above the surface of a fastener or shaft that assists in temporarily securing another part to the fastener shaft, but does not alter or interfere with the final assembly of the parts.
Still another object of the present invention is to provide a flexible compressible deposit of material on a portion of a fastener of a preselected shape and height that is related to the speed of rotation of the fastener during application.
These and other objects are satisfied by a method of making retaining elements on parts comprising the steps of providing a spindle, supporting the spindle in a manner such that the spindle is capable of rotation, removably attaching a part to the spindle, rotating the spindle with the part attached thereto, heating the part, sensing whether a part is present on the spindle, supplying a discrete shot of molten liquid material that solidifies upon cooling onto a preselected portion of the part if the part is sensed in the sensing steps, and continuing to rotate the spindle after the material has been supplied in the supplying step at a speed capable of generating centrifugal force sufficient to urge the molten liquid material supplied in the supplying step to extend substantially above the surface of the part when it solidifies. These and other objects of the invention will become more apparent as the following description proceeds, especially when considered with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevational view of the apparatus used in the practice of the present invention.
FIG. 2 is an end elevational view of the apparatus shown in FIG. 1.
FIG. 3 is a side view of a typical fastener processed in accordance with the present invention.
FIG. 4 is a cross-sectional view of the fastener taken along the line 4--4 in FIG. 3.
FIG. 5 is a partial side view taken along the line 5--5 in FIG. 1.
FIG. 5A is a partial front view of illustrating the application of material onto a fastener in accordance wtih the embodiment of the present invention.
FIG. 6 is a partial side view of a portion of the wheel of the present invention.
FIG. 7 is a side view of another fastener processed in accordance with the present invention.
FIG. 8 is a cross-sectional view of the fastener taken along the line 8--8 of FIG. 7.
FIG. 9 is a front view of a mechanical part holder of the present invention.
FIG. 10 is a partial side-sectional view taken along the line 10--10 in FIG. 9.
FIG. 11 is a front view of a second type of mechanical part holder for use in conjunction with the present invention.
FIG. 12 is a partial side-sectional view taken along the line 12--12 in FIG. 11.
FIG. 13 is a front view of another mechanical part holder that can be utilized in conjunction with the present invention.
FIG. 14 is a partial side-sectional view taken along the line 14--14 in FIG. 13.
DETAILED DESCRIPTION OF THE INVENTION
Referring now more particularly to the drawings and especially to FIGS. 1-2 and 5-6 thereof, the apparatus 10 there illustrated comprises a wheel 20 in the form of a circular disc which is mounted for rotation and a vertical plane about its central axis on a horizontal shaft 18 to which it is affixed. The shaft 18 is rotatably mounted in bearing blocks 17 on the frame 16.
The wheel 20 has a plurality of parts holding pins 40 near its outer edge. The pins 40 are preferably arranged in equally spaced relation in a circle concentric with the axis of rotation of the wheel 20. Bearings support each pin 40 for axial rotation. The pins 40 extend at substantially right angles to the plane of the wheel 20 and are therefore horizontal and present a substantially flat end surface to attach parts 12 thereto. A variable speed motor 30 mounted on a stand 72 drives the wheel 20 by means of a chain 52 extending around a sprocket 54 on the output shaft of the motor 30 and also a sprocket 60 on the shaft 18.
The pins 40 can be magnetized in order to retain the parts 12 during the processing operation or they could be provided with removable mechanical attachment elements 84a, 84b and 84c, such as illustrated in FIGS. 9-13 respectively. These attachment elements 84a, 84b and 84c, are adapted to slip fit over the pins and provide mechanical attachment of threaded elements such as 90, 91 or 92 and non-threaded elements alike. The exemplary elements illustrated in FIGS. 9-13 demonstrate that through their use a wide variety of parts having regular or irregular shapes, configurations and/or end surfaces can be processed by the present invention.
As particularly illustrated in FIGS. 5 and 6, each pin 40 has a sprocket 60 located along its length that extends outwardly beyond a portion of the outer surface of its construction. An endless chain 38 extends around the wheel 20 in engagement with a number of the sprockets 60 and is driven by a sprocket 64 on the output shaft of a variable speed motor 62 carried by the frame 16. During operation of the device 10 only a small number of the sprockets 60 nearest the motor 62 are out of contact with the chain 38 at any given moment. The remaining sprockets 60 are in contact with and are continuously rotated in a preselected direction by the chain 38.
A reservoir 66 is mounted on the frame 60 above the wheel 20. The reservoir 66 contains a supply of heated liquid thermoplastic, thermoset, hot melt or PVC material. Although a variety of these materials can be used, it has been found that polyamide is a hot melt material that is particularly well suited for use in this invention. An example of such a material is polyamide #108100/HM-0904 sold by H. B. Fuller & Co. Deposits made of this material are particularly preferred since they exhibit improved temperature and chemical resistance over materials such as amorphous polypropylene.
Polyamides are flowable under pressure and have no or minimal elastic qualities such that once it is used it normally cannot be reused. They are tough yet deformable, it has no "cure" feature or requirement. They are available in several grades from softer to harder and is insoluble in all common fuels including ketones, alcohols, oils (natural and synthetic) and dilute acids. Such materials are heat flowable. When cooled to room temperature they show almost no deposit to deposit tack making them ideal for the bulk handling of parts to which the material 14 is applied. Numerous fillers can be added to the hot melt material particulates ranging from powdered nylon, glass, silicon, clay, graphite or metals can be used for various effects.
As particularly illustrated in FIGS. 1 and 2, the reservoir 66 is connected to a support 68 attached to frame 16. The material is supplied from the reservoir 66 through at least one opening in the bottom thereof to a suitable fluid delivery device such as one or more guns 46. As will be discussed in more detail hereafter, each gun 46 utilized is provided with a stage 48 that serves to secure and support the gun 46. The stage 48 is important to the precision of the ultimate delivery of material 14 from the gun 46 since it allows the adjustment of the gun 46 in up to three different distinct axes. Stage 48 also permits an attachment means that enables rotational movement of the gun 46 about its point of attachment. Many different known stages can be utilized in connection with the present invention as long as they provide for the selective adjustment of the position of the gun 46 along a number of different axes. A particularly suitable commercially available stage has been found to be the 4500 Series ball bearing stage manufactured by the Daedal Division of Parker Corporation of Harrison City, Pa.
The stage 48 also provides a point of attachment for an optical sensor holder 51 that houses an optical sensor 50. The optical sensor 50 is directed in a manner so that it senses whether a pin 40 or a part 12 such as a fastener is present. Once a part is sensed, the sensor 50 then sends a signal causing a precisely metered shot of liquid material 14 to issue from the gun 46 only when it is indicated that a part 12 is appropriately located under the nozzle 44 of the gun 46. The sensor 50 is therefore in communication with the electro-pneumatic firing mechanism of the gun 46 to control the timing of the output of material 14 therefrom. Although a number of different sensors are acceptable, a particularly preferred sensor for use with the present invention has been an OMRON photoelectric switch (Model E3A2-XCM4T).
The gun 46 fires precisely timed shots or droplets of material 14 in response to an indication from the sensor 50 that a part 12 is present and properly aligned under the nozzle 44. The present invention can utilize either single or multiple guns 46 to deposit material 14 onto parts 12. A single gun 46 produces a single deposit of material 14 on each part, such as illustrated in FIG. 7 for example. Alternatively, multiple guns can produce multiple deposits of material 14 in many different forms such as, for example, the deposits 15 and 15a.
The gun 46 must be capable of precisely controlling the amount, direction and speed of each metered shot of material 14 that it deposits. Additionally, the gun 46 must also have the capability of metering a high number of discrete shots of material 14 per unit of time and provide consistent clog-free operation and efficient cut off of material flow without dripping.
At times it is preferred that the gun 46 is heated in some manner so as to maintain additional control over the viscosity of the material 14 exited through the nozzle 44. It is preferred that the gun 46 have a maximum operating temperature of about 450° F. and an operating air pressure in the range of approximately 30-100 psi or at least 60-100 psi. The gun should also have a working hydraulic pressure of at least 1500 psi and be capable of operating at speeds exceeding 3500 cycles per minute. The diameter of the gun should be between 0.008 and 0.040 inches. A commercially available gun that has been found to be particularly useful in meeting or exceeding these parameters is the Nordson H-201 gun with a zero cavity module manufactured by Nordson Corporation of Norcross, Ga.
The frame 16 also provides a point of attachment for a heater 26 such as illustrated in FIG. 1. The heater 26 can take many different forms including an infrared heater or an induction heater. The heater serves to sufficiently increase the temperature of the parts that pass through it to a temperature sufficient to maximize the ability of the material 14 to form discrete deposits 15 that are raised above the surface of the parts 12 such as fasteners shown in FIGS. 3-4 and 7-14. The heater 26 also serves to improve the adhesion of the material 14 ultimately deposited on the parts 12.
Downstream from the heater 26 and gun 46, a rinse tank 28 is provided that has a reservoir of a cooling material. The tank 28 is connected to a rinse nozzle 34 that selectively deposits cooling fluid onto the area of the parts 12 that pass by it in order to insure that the material 14 deposited thereon is solidified prior to collection and packaging. Although a variety of cooling materials can be used, it has been found efficient in most circumstances to utilize cool air or water that is at room temperature or slightly cooled.
Located downstream of the rinse tank 28 and near the bottom of wheel 20 on one side thereof a stripper 58 is provided comprising a plate supported by a stand 59. The stripper 58 is provided at the angle shown in FIG. 1 in relation to the parts 12 on the pins 40. The stripper 58 extends across the paths of the parts 12 to force the then processed parts 12 from their respective pins 40 as the rotation of the wheel 20 forces successive parts 12 into contact with the stripper 58. The parts 12 are removed from the pins 40 as the stripper 58 breaks either the magnetic attraction between the parts 12 and the pins 40 or the mechanical connection between the two. The parts 12 then fall under the force of gravity onto a finished parts conveyor 88 for ultimate packaging or for additional processing. Alternatively, other known structures and methods such as a pneumatically driven plunger could be used to strip the parts 12 from the pins 40 if additional removal force is desired.
The operation of a preferred embodiment of the present invention will now be described in more detail. The apparatus 10 of the present invention is first powered up so that the motor 62 is rotating the wheel 20 in a clockwise direction in the embodiment shown in FIG. 1 and so that the motor 30 is enabling rotation of each of the individual pins 40 that are in contact with the chain 38 in a clockwise direction, the same as the direction of rotation of the wheel 20. As will be described below in more detail, the motor 30 allows the speed of rotation of the pins 40 to be varied in order to affect the shape and height of the deposit 15 of material 14 on the parts 12.
With the wheel 20 and pins 40 rotating at their respective preselected speeds, parts 12 such as fasteners are introduced to the pins 40 in a continuous spaced manner. Delivery of the parts 12 is indexed such that a single part 12 is provided to each pin 40 that passes by the point of introduction of the parts. Parts 12 can be deposited onto the pins 40 of the rotating wheel either manually or by many known parts delivery systems such as a vibratory feeder 22 connected to an angled track 24 as illustrated in FIG. 1. Although not required, it has been found to be somewhat advantageous to attach parts 12 to the pins 40 before the individual sprockets 60 engage the chain 38 to begin rotation of the pins 40.
As previously mentioned, the parts 12 are retained in position on the pins 40 either by magnetic forces or mechanical holding elements such as 84a, 84b and 84c. Once each part 12 is attached to its respective pin 40, its sprocket 60 then engages the chain 38 to rotate that pin 40 and then part 12 attached thereto. With the parts 12 attached to the individual rotating pins 40 the wheel 20 continues to rotate the parts 12 toward the heater 26. The parts 12 first are preheated to a temperature near the melt point of the material 14 by the heater 26. This is required to insure that the material 14 will adhere well to the surface of the parts 12.
The still rotating parts 12 then pass by the gun 46. As they pass by the sensor 50, each part 12 is shot with a single bead of viscous molten material 14 which is deposited at a selectively desired location along the length of the part 12 by the gun 46 in response to a sensor signal. Due to the adjustability of the gun 46 the material 14 can be deposited virtually anywhere along the length of the parts 12 as illustrated by example in FIGS. 3, 4, 7, 10, 12 and 14. As also illustrated in these figures, it is usually desired with respect to the present invention to provide an ultimate deposit 15 of material 14 on each part 12 that once applied remains projecting substantially above the surface of each part 12 and does not flow out flat on the surface of each part 12 once the material 14 contacts the part 12.
Alternatively, as illustrated in FIGS. 1 and 3 the present invention can provide more than one discrete deposit of material 14 on a single part 12, such as deposits 15 and 15a, by using multiple guns 46 and sensors 51. The present invention can be utilized to form deposits that selectively extend from a small portion to the entire 360° circumference of a given part. Additionally, modifying the flow rate of the material 14 from the guns 46, and/or the speed of rotation of the parts 12, more elongated deposits or ring type deposits 15a can be formed by the present invention alone or in combination with bead type deposits 15. Also, the present invention can be used to retain a washer or other element on a part 12 by sliding the washer 71 over the part 12 prior to depositing any material 14 onto the part 12.
When it is desired to form bead type deposits 15 on parts 12, it has been found that the rotation of the pins 40 and therefore the parts 12 attached thereto and the precise placement of the shot of material 14 issuing from the gun 46 are key elements in keeping the bead of material 14 that contacts each part 12 from flowing out flat on the surface thereof. Referring specifically to FIG. 5A, the detail of the placement of a discrete shot of material 14 onto a part 12 rotating on a pin 40 is illustrated. The shot of material 14 is placed on the far side A of the part 12 that is moving toward the nozzle 44 as opposed to the side B of the part 12 that is moving away from the nozzle 44. This causes the molten material 14 to bunch up into a bead-like deposit 15.
The rotation speed of the pins 40 is preadjusted so that the resulting centrifugal force offsets the tendency of the then deposited liquid material 14 to flow out flat, but is not so great as to throw the liquid off of the part. Without a significant rotation speed of each of the pins 40 and therefore the parts 12 attached to them there would be little or no projection of the deposits 15 of material 14 above the part surface. If the height of the finished deposit is not great enough then insufficient retention ability results in the ultimate deposit 15 of material 14 on the part 12 which does not serve to temporarily retain the part 12 in relation to another part in contemplation of further ultimate assembly. It has been found that, in order to achieve the desired effect and produce an appropriately shaped bead type deposit 15 that projects sufficiently above the surface of the parts 12, that pin rotation speeds on the order of about 100-150 rpm are preferable.
In the case of placing a deposit 15 of material 14 on the threads of threaded fasteners in particular, it is often necessary to create a significantly larger diameter projection along the outer surface of the fastener to meet the temporary retention pull off force necessary for a given specification. This is usually best accomplished by shooting a long bead of material 14 from the gun 46 which tends to lay down lengthwise in the thread grooves. The result is a crescent shaped deposit of material whose projection above the part surface has a broader radial extent. The ability of the guns 46 to vary the amount and volume of material 14 and timing of a given shot of material and precision placement of the shot allows this capability. As such, the present invention can be utilized to provide deposits of material 14 on parts 12 along any portion of the entire 360° circumference of a part 12.
Once the parts 12 leave the area of the one or more guns 46 that are present they are then moved by the wheel 20 to allow sufficient time while they are still rotating on their individual pins 40 for the base of the deposit 15 of material 14 to wet on the parts 12 and for the deposit 15 to attain the final desired shape. The centrifugal force resulting from the rotation of the pins 40 and parts 12 continues to encourage the material 14 to remain upwardly extending from the surface of the parts 12 and avoid the tendency of the liquid material 14 to flow out flat. The parts 12 are then further cooled either with blowing air or a water quench 34 in order to further harden the material 14 deposited thereon.
As the wheel continues to rotate, each coated part 12 next encounters the stripper 58 which breaks the connection between the individual pins 40 and the parts 12. By the time each part 12 encounters the stripper 58, it is at times preferable to insure that the sprocket 60 of each pin 40 is still in contact with the chain 38 so that the part 12 and pin 40 are still spinning to assist in breaking the connection to remove the parts 12. Once removed, the parts 12 then fall down under the force of gravity until they encounter a conveyor belt 88 which carries them away from the area of the wheel 20. If the cooling medium used was water, then an additional conveyor 31 can be provided that removes the parts 12 from the conveyor belt 88 and directs them past an off-line dryer 32 in order to dry any water that may be remaining on the parts 12 prior to ultimate packaging.
The following example is given to aid in understanding the invention and it is to be understood that the invention is not limited to the particular procedures or the details given in this example.
EXAMPLE I
In one production run, cold headed M-14 flange bolts were deposited on successive rotating magnetic pins on a 4 foot diameter wheel that had 100 parts holders or pin positions. The wheel was travelling at a speed such that it took approximately two and one half minutes to complete one full rotation. The parts were fed to the pins by a vibratory feeder bowl and track. The individual bolts were attached one to each successive pin and retained by the magnetic attraction of the pins.
The pins and bolts were rotated at a rate of 130 rpm as the bolts on the rotating pins were rotated by the wheel in the same direction as the rotation of the individual pins. The bolts were then passed through a 25 kilowatt low frequency induction heater set at 10 kilohertz or an 80 setting. The heaters increased the ambient temperature surrounding the bolts to 350° F. at the area where the bolts exited the heater.
The bolts then were each supplied with a bead of polyamide material on a preselected portion of their length. The polyamide material had a viscosity of 6000 cps at 400° F. and were metered using a single Nordson Zero Cavity Module H-201 gun. As the rotating parts were moved by the wheel further away from the gun, they next encountered a water and mist quench to cool the fasteners. This cooling process cooled the fasteners to approximately 120° F. Once the fasteners left the cooling area they were stripped and dropped onto a conveyor belt for ultimate packaging.
The bolts that were processed had a bead of material of the size and type illustrated in FIGS. 7-8. The deposited bead of material extended a sufficient distance above the surface of the bolts so as to be acceptable in shape to retain another part in place pending ultimate assembly and the circumferential extent of the material did not extend beyond an acceptable region. The polyamide material on the bolts was then tested for a pull off force and results indicated that they would withstand a 20 lb pull off force. From this example it is clear that the present invention was demonstrated to produce very effective desired results.
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A method and apparatus for the application for one or more deposits of material to a succession of discrete articles such as fasteners as is provided. The method and apparatus of the present invention deposits a droplet or extended bead of thermoplastic or thermoset material onto the surface of a part that is urged into a postion once it solidifies to extends above the surface of the part to create assembly resistance when the part is assembled into or over another part.
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This application is a national stage completion of PCT/EP2005/012710 filed Nov. 29, 2005 which claims priority from German Application Serial No. 10 2004 057 848.6 filed Dec. 1, 2004.
FIELD OF THE INVENTION
The invention relates to an adjustable hysteresis driver.
BACKGROUND OF THE INVENTION
Hysteresis drivers in the form of hysteresis clutches or hysteresis brakes have long been known in many forms. The advantage of such clutches or brakes consists essentially in their ability to transmit torque without contact, across an air gap. The way these devices work relies on the magnetic force action of mutually attracting poles in synchronous operation or a continual magnetic reversal of a permanently magnetic hysteresis material moved past these poles in slipping operation. For example electromagnetically energizable hysteresis clutches are known from DE 39 05 216 A1 and DE 199 17 667 A1, whose transmitted torque can be adjusted as a function of the current flowing through an energizing coil.
In addition, from DE 37 32 766 A1 a permanent-magnet-energized hysteresis clutch is known, in which the torque to be transmitted can be changed by manually varying the insertion depth of an annular hysteresis element into an air gap formed between two pole rings of the permanent magnet.
Furthermore, from DE 2 261 708 A it is known to operate a hysteresis clutch of an auxiliary aggregate drive of a motor vehicle in such manner that it is activated or deactivated as a function of the temperature of the coolant liquid or oil of an internal combustion engine. This hysteresis clutch comprises electromagnets that can be switched on, i.e. a plurality of electromagnetic fields, with poles complementary to one another.
Moreover, from DE 197 46 359 C2 and DE 100 18 721 A1 adjustable coolant pumps for motor vehicles with hysteresis clutches are known. The first of these documents describing a permanent-magnet-energized hysteresis clutch, one clutch half of which can be displaced axially by means of an electrically driven adjustor unit so that the gap width of the air gap between the two halves of the clutch, and consequently the torque to be transmitted, can be varied as a function of the operating condition of the combustion engine. On the other hand DE 100 18 721 A1 concerns an electromagnetically energized hysteresis clutch by which the torque to be transmitted can be regulated or adjusted as a function of the size of the current flowing through the coil of an electromagnet.
These known hysteresis clutches are similar in that they all use electric or electro-mechanical regulation of the torque transfer, which is associated with the disadvantage that if the current supply to such hysteresis clutches should fail, they can no longer carry out their intended purpose.
Against that background the purpose of the present invention is to propose a hysteresis driver, such as a hysteresis clutch or a hysteresis brake, whose adjustment or regulation is improved, in that on the one hand it enables continuously variable torque adjustment and on the other hand it can still transmit torque even if the current supply has failed. Such a hysteresis driver should for example also be suitable for use as an auxiliary drive of a motor vehicle engine or an auxiliary drive output.
SUMMARY OF THE INVENTION
Accordingly, the invention starts with an adjustable hysteresis driver having a rotor component on the input side that can be driven mechanically and/or a stator component, with an armature component in rotationally fixed connection with a shaft, with a hysteresis component connected to the armature component, the stator component comprising at least one electromagnet or permanent magnet by means of which a magnetic flux can be induced in the rotor component and/or the stator component, and in which the torque that can be transmitted is adjustable electromagnetically or electro-mechanically, for example, by a servomotor which adjusts the insertion depth. To achieve the stated objective it is also provided that the hysteresis drive is formed by a hysteresis clutch or a hysteresis brake, and has an active means for implementing a “fail-safe” function which, in the event of a failure of the current supply to the electromagnet, ensures that torque is still transmitted between the rotor component of a hysteresis clutch or the stator component of a hysteresis brake and the armature component, by virtue either of a mechanical coupling or the force of a permanent magnet.
Thanks to this measure it is advantageously ensured, for example when the hysteresis clutch is used in an auxiliary drive of an internal combustion engine of a motor vehicle, that even in the event of a failure of the current supply to the energizing coil of the electromagnet, torque can still be transmitted from the input side to the output side of the clutch. This can, for example, be particularly important if the auxiliary drive of the combustion engine drives a vehicle cooling system with the crankshaft of the combustion engine via the hysteresis clutch, the system being required to dissipate heat even when the current supply has failed or is defective.
In the case of a hysteresis brake formed according to the invention it should be noted that if the current supply to the energizing coil of the electromagnet fails, again torque—in this case a negative torque—can be transmitted to the armature and the shaft connected thereto, which can be a shaft connected to an auxiliary component.
In the case of a hysteresis clutch developed according to the invention, the means for implementing the “fail-safe” function in a first variant of the invention comprises at least a first mechanical clutch element that is connected in a rotationally fixed manner to the rotor component, but is able to move axially, which in the event of failure of the current supply to the electromagnet, can be connected frictionally and/or with a form-fit to a second mechanical clutch element which is in fixed connection with the armature component
In contrast, in the case of a hysteresis brake the means for implementing the “fail-safe” function comprise at least a first mechanical clutch element connected directly and in a rotationally fixed manner to the stator component but is able to move axially, such that in the event of failure of the current supply to the electromagnet, it can be connected frictionally and/or with a form-fit to a second mechanical clutch element which is in fixed connection with the armature component.
Furthermore, according to the invention the first mechanical clutch element is preferably a brake disk and the second mechanical clutch element is preferably a friction lining.
In another embodiment of the invention, however, the two mutually corresponding mechanical clutch elements can also be components of a gear-type coupling.
It is also regarded as expedient for the first mechanical clutch element to be adjustable by the force of a spring in the axial direction relative to the corresponding, second mechanical clutch element, but during normal operation is fixed by magnetic force on the rotor component of a hysteresis clutch or on the stator component of a hysteresis brake. This magnetic force for the local fixation of the first mechanical clutch element is produced by the energizing coil of the electromagnet or by the energizing coil of a separate, additional electromagnet.
It is also preferable to provide an overload protection system which reduces and/or removes an existing frictional and/or interlocking connection made between the two clutch elements. This enables parts, for example, of an auxiliary component drive or auxiliary drive output that co-operate with the hysteresis clutch or hysteresis brake, to be protected effectively against damage.
According to a second variant of the invention, the hysteresis driver can be made such that to enable adjustment of its torque transmission capacity there is associated with at least one permanent magnet at least one electromagnet whose magnetic field changes or counteracts that of the permanent magnet as a function of the voltage applied. In this case, the means for implementing a “fail-safe” function of the hysteresis driver consist of the permanent magnet itself, whose magnetic field, if the current supply to the electromagnet fails, continues to function normally and accordingly ensures that the rotor component of a hysteresis clutch or the stator component of a hysteresis brake is coupled with the armature component for torque transmission.
In contrast, in a third variant of the invention, to adjust the torque transmission capacity of the hysteresis driver, an electro-mechanical adjustor unit is provided to vary the overlap between the rotor component of a hysteresis clutch or the stator component of a hysteresis brake and the hysteresis component, such that the means for implementing a “fail-safe” function are formed by at least one spring element which, if the current supply to the electromagnet fails, automatically moves the rotor component of the hysteresis clutch or stator component of the hysteresis brake and the hysteresis component including the armature component into a position relative to one another such that torque transfer is ensured.
BRIEF DESCRIPTION OF THE DRAWINGS
To clarify the invention, drawings are attached and described and show in.
FIG. 1 is a sectional view of a hysteresis driver according to the invention, in the form of a first embodiment of a hysteresis clutch;
FIG. 2 is a sectional view of a second embodiment of the hysteresis clutch according to the invention;
FIG. 3 is a sectional view of a hysteresis driver according to the invention, in the form of a first embodiment of a hysteresis brake; and
FIG. 4 is a sectional view of a second embodiment of the hysteresis brake according to the invention.
DETAILED DESCRIPTION OF THE INVENTION
The hysteresis clutch shown in FIG. 1 comprises an energizing unit 1 and a hysteresis unit 2 , which co-operate in relation to the functionality of the hysteresis clutch. The energizing unit 1 comprises, first, a rotor component 5 which is rotationally supported via a ball bearing 3 on a shaft 4 , which is in this case a drive output shaft, and is made as a traction sheave which can be driven, via flexible wrap-around means (not shown), by the crankshaft of a combustion engine of a motor vehicle. In addition there is a stator component 7 ′ which is connected to a fixed housing 6 and which comprises an electromagnet 7 a , that in part coaxially surrounds the shaft 4 and a section of the rotor component 5 close to the shaft.
The hysteresis unit 2 is formed by a rotationally symmetric armature component 8 , which is connected in a rotationally fixed manner to the radially inner shaft 4 , and on the radial outside comprises a hysteresis component 9 in the form of an axially extending hysteresis annulus made of a known homogeneous hysteresis material.
The shaft 4 is supported by a ball bearing 10 on the fixed housing 6 and is connected to an auxiliary component not shown in more detail, which can for example be a coolant pump or a fan.
The hysteresis component 9 , formed as a hysteresis ring, extends axially into an axially extending air gap 11 in the rotor 5 , which is made of a magnetically soft material, without contacting the latter. When an electric voltage is applied to the energizing coil of the electromagnet 7 a of the stator component 7 ′, the flow of current through the coil produces a magnetic field which induces a magnetic flux, in the driven rotor component 5 having pole to pole alternating polarity. Rotation of rotor 5 causes in the hysteresis material of the hysteresis component 9 to continually reorient of elementary magnetic domains, whereby a torque is exerted on the armature component 8 in fixed connection with the hysteresis component 9 . The shaft 4 , connected in a rotationally fixed manner with the armature component 8 then transmits the torque to the connected auxiliary component.
For those with an understanding of the subject it is easy, with knowledge of the invention, to perceive that if the current supply to the electromagnet 7 a fails, the electromagnetic coupling between the rotor component 5 and the armature component 8 is interrupted because the necessary magnetic fields of the electromagnet 7 a that are produced in alternation with one another can no longer be formed. This can lead to critical operating conditions of the combustion engine and/or other parts of a motor vehicle that rely on proper operation of the auxiliary component.
To be able to overcome this critical operating situation effectively, according to the invention at least one active operating means for implementing a so-termed “fail-safe” function of the hysteresis clutch is provided, which, even if the current supply to the electromagnet 7 a has failed, ensures a defined coupling between the rotor component 5 and the armature component 8 in order to transmit a torque from the combustion engine to the auxiliary aggregate.
According to the variant of the invention shown in FIG. 1 , the means for implementing this “fail-safe” function of the hysteresis clutch consist of at least a first axially slidable mechanical clutch element 12 connected in a rotationally fixed manner to the rotor component 5 , which, if the current supply fails, can be connected frictionally and/or with a form-fit interlock to a second mechanical clutch element 13 which is fixed in connection to the armature component 8 .
In the present case, the first mechanical clutch element 12 is formed as a friction disk. Expediently, it consists of a magnetic ferrous material. The first mechanical clutch element 12 can be attached in a rotationally fixed and axially movable manner to the rotor component 5 , for example by means of guide bolts or screws 14 located in guide holes 15 of the rotor component 5 .
In the embodiment illustrated, the first mechanical clutch element 12 can, for example, be pressed by a spiral compression spring 17 b against the frictional surface 13 on the armature component 8 .
Alternatively, the first mechanical clutch element 12 is connected to a membrane spring 17 a , which can also transmit torque and which allows axial movement of the clutch element 12 . This membrane spring 17 a is connected to the rotor component 5 , for example, by screws.
To produce a magnetic tensile force on the first mechanical clutch element 12 , magnetic isolation is required in the rotor component 5 , in the material of which the guide bolts or screws 14 or the spiral compression springs 17 b are arranged.
During normal operation, i.e. when an electric current is flowing through the windings of the energizing coil of the electromagnet 7 a , the current flow produces a magnetic field, which on one hand induces a magnetic flux in the driven rotor component 5 , but on the other hand also secures the first mechanical clutch element 12 on the rotor component 5 by means of magnetic force against the spring force of the spring elements 17 .
Instead of the magnetic force produced by the energizing coil of the electromagnet 7 a , the magnetic force of the energizing coil of a separate, additional magnet can also be used to fix the first mechanical clutch element 12 to the rotor component 5 (this option not being illustrated).
When the current flow through the energizing coil of the electromagnet 7 a fails due to a defect, the spring elements 17 press the first mechanical clutch element 12 (the friction disk) against the second mechanical clutch element 13 (the friction lining), thereby producing a frictional engagement that ensures torque transmission from the input side to the output side of the hysteresis clutch.
By virtue of the spring force of the spring elements 17 , a minimum transmissible force between the two mechanical clutch elements 12 and 13 can be set to prevent overload of components and assemblies such as a drive belt.
Instead of frictional engagement between a friction disk and a corresponding friction lining, according to another variant of the invention, means can also be provided to establish a form-fit interlocking engagement between the rotor component 5 and the armature component 8 of the hysteresis clutch. Suitable for this are, for example, clutch elements of a gear-type clutch, known as such, and preferably of annular shape (not shown), which can be brought into interlocking engagement with one another.
Following the principle of the preceding embodiment, the clutch elements of such a gear-type clutch are also made from a ferrous material and are kept apart by the magnetic force during normal operation, i.e. when current is flowing through the energizing coil of the electromagnet 7 a . Only if the current supply to the electromagnet 7 a has failed are these two mechanical clutch elements also brought into mutual interlocking engagement by a spring force.
FIG. 2 shows a second embodiment of the hysteresis clutch made in accordance with the invention. This differs from the hysteresis clutch described above essentially in that the rotor component 5 can be activated by at least one permanent magnet 18 fixed on the stator component 7 ′ instead of electromagnetically.
For adjusting of the torque that can be transmitted by the hysteresis clutch, this at least one permanent magnet 18 is associated with at least one electromagnet 19 , which is also fixed on the stator component 7 ′. As a function of the applied voltage or the current flowing through the electromagnet 19 , the electromagnet 19 offsets the magnetic field of the permanent magnet 18 , to a greater or lesser extent, so that a greater or lesser amount of slip exists between the rotor component 5 and the hysteresis unit 2 , which comprises the armature component 8 and the hysteresis component 9 attached thereto, whereby the amount of torque through the hysteresis clutch can be adjusted.
If the current supply to the electromagnet 19 fails due to a functional defect, the magnetic field of the permanent magnet 19 remains fully active such that a defined torque is transmitted to the armature component 8 , the shaft 4 fixed thereto, and the hysteresis component 9 , and thus to the auxiliary component.
In a third possible design variant of the invention (not illustrated) the starting point is a hysteresis clutch, with rotor component 5 , that can be activated by at least one permanent magnet 18 and in which the clutch torque is adjusted by an electro-mechanical adjustor unit which changes the overlap or separation between the rotor component 5 and the hysteresis component 9 . Such an electro-mechanical adjustor unit, known in its own right, is described for example in DE 197 46 359 C2.
To implement a “fail-safe” function in a hysteresis clutch of this type, according to the invention at least one spring element is provided, which, if the current supply to the electro-mechanical adjustor unit fails, automatically brings the rotor component 5 and the hysteresis component 9 to a position relative to one another which ensures coupling of the rotor component 5 to the hysteresis component 9 with the armature component 8 for transmitting a torque from the input side to the output side of the hysteresis clutch.
The embodiments described above are based on a hysteresis driver in the form of a hysteresis clutch. However, the invention also includes a hysteresis brake, which essentially applies a negative torque to an armature component 8 in that is connected rotationally fixed manner with a shaft 4 . The shaft 4 can, for example, be a driven connecting shaft attached to an auxiliary component (not shown).
According to FIGS. 3 and 4 , the design of the hysteresis brake in question differs from that of the hysteresis clutch described earlier, first and foremost only in that in this case there is no need for a rotor component 5 . The hysteresis component 9 made as an axially extending hysteresis ring now extends directly axially into an also axially extending air gap 11 of the stator component 7 ″, which is made of a magnetically soft material and contains the electromagnet 7 a . When an electric voltage is applied to the energizing coil of the electromagnet 7 a of the stator component 7 ″, the current flowing in the coil produces a magnetic field which, as is known, leads to a continuous reorientation of elementary magnetic domains in the hysteresis material of the hysteresis component 9 being rotationally driven by an external force via the shaft 4 and the armature component 8 , whereby in turn a negative torque in the sense of a braking force can be applied on the armature component 8 which is fixed with the hysteresis component 9 , and hence on the shaft 4 .
To deal effectively, in this case too, with the critical operating situation when the current supply to the electromagnet 7 a fails, i.e. to implement a “fail-safe” function, a first mechanical clutch element 12 of the type described earlier is again provided, which, in the event of current supply failure, can be brought into frictional and/or a form-fit engagement with a second mechanical clutch element 13 , which is fixed with the armature component 8 . In contrast to the hysteresis clutch, however, the first mechanical clutch element 12 is now supported directly on the stator component 7 ″ and is therefore in a fixed position ( FIG. 3 ).
With regard to the other design features and particular operating modes of the clutch elements 12 , 13 as a friction disk/friction lining combination or as a gear-type coupling, there are no differences compared with the hysteresis clutch described earlier, so no corresponding explanations are needed and in the figures the same reference numerals are used for the same components.
FIG. 4 shows a hysteresis brake which, like the principle of the hysteresis clutch illustrated in FIG. 2 , can be energized instead of electromagnetically by at least one permanent magnet 18 fixed on the stator component 7 ″.
At least one electromagnet 19 is again associated with the at least one permanent magnet 18 for adjusting a negative torque or braking torque that can be transmitted by the hysteresis brake to the shaft 4 . As a function of the voltage applied or the current flowing through the electromagnet 19 , the magnetic field of the electromagnet 19 offsets the magnetic field of the permanent magnet 18 , to a greater or lesser extent, whereby the magnitude of the negative torque produced by the hysteresis brake can be adjusted.
If the current supply to the electromagnet 19 fails because of a defect, the magnetic field of the permanent magnet 18 remains fully active and as a result a defined negative torque is transmitted to the armature component 8 to which the shaft 4 and the hysteresis component 9 , and hence to the auxiliary aggregate.
According to a third possible design variant (not shown), the starting point is a hysteresis brake which can be activated by at least one permanent magnet 18 , which is fixed on the stator component 7 ″. As already described earlier for the hysteresis clutch, the negative torque to be applied can here too be adjusted by means of an electro-mechanical adjustor unit which changes the overlap or separation between the stator component 7 ″ and the hysteresis component 9 .
To implement a “fail-safe” function in a hysteresis brake of this type, a spring element is again provided, which, if the current supply to the electro-mechanical adjustor unit fails, automatically brings the stator component 7 ″ and the hysteresis component 9 to a position relative to one another that ensures a coupling between the stator component 7 ″ and the hysteresis component 9 with its armature component 8 , so that a defined negative torque is transmitted.
INDEXES
1 Energizing unit
2 Hysteresis unit
3 Ball bearing
4 Shaft
5 Rotor component
6 Housing
7 ′, 7 ″ Stator component
8 Armature component
9 Hysteresis component
10 Ball bearing
11 Air gap
12 First mechanical clutch element (on the rotor component 5 or the stator component 7 ″)
13 Second mechanical clutch element (on the armature component 8 )
14 Guide bolts, screws
15 Guide holes
16 Magnetic isolation
17 Spring elements
17 a Membrane spring
17 b Spiral compression spring
18 Permanent magnet
19 Electromagnet
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The invention concerns an adjustable hysteresis driver, with a rotor component ( 5 ) on the input side that can be driven and/or a stator component ( 7′, 7″ ), with an armature component ( 8 ) on the output side in fixed connection with a shaft ( 4 ), with a hysteresis component ( 9 ) connected to the armature component ( 8 ), the stator component ( 7′, 7″ ) comprising an electromagnet ( 7 a ) or permanent magnet ( 18 ) by means of which a magnetic flux can be induced in the rotor component ( 5 ) and/or the stator component ( 7′, 7 ″), and in which the torque that can be transmitted can be adjusted by electromagnetic or electro-mechanical means. The purpose of the invention is to propose a hysteresis driver with improved adjustability. To achieve this it is provided that the hysteresis driver consists of a hysteresis clutch or a hysteresis brake and has active operating means for implementing a “fail-safe” function, which, if the current supply to the electromagnet ( 7 a ) fails, ensures that a torque is transferred either by a mechanical coupling or by the action of permanent magnet force between the rotor component ( 5 ) of a hysteresis clutch or the stator component ( 7 ″) of a hysteresis brake and the said armature component ( 8 ).
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BACKGROUND OF THE INVENTION
This invention relates to a vehicle door clamping mechanism and more particularly to a clamping mechanism for use by law enforcement officers to secure a front vehicle door in the closed position while interviewing a suspect seated in the vehicle.
In most situations, law enforcement officers do not know if a person pulled over for a traffic violation has a criminal record. The officer must approach the stopped vehicle with caution. While an officer can assume that every driver he stops is potentially dangerous, he cannot treat every citizen as though he were a wanted criminal. Thus, an officer must be alert to circumstances calling for quick action when approaching a vehicle, but he should not restrain a citizen without cause.
When an officer approaches a vehicle after requiring it to stop, preferred procedures call for the driver to remain in the vehicle and communicate with the officer through the driver's window. As the officer approaches the car to speak with the driver, he reaches a position where, if the driver's door were suddenly thrust open, the officer would be hit by the door. In order to prevent this from happening, an officer needs a device capable of securing the vehicle door in the closed position. Furthermore, the device must be such that the officer can use it with one hand (the hand not used to draw his or her weapon) and before he enters the dangerous area where the door would hit the officer. In addition, the device should be such that it can be applied to the vehicle quickly, and without damage to the vehicle. Once attached, the device must be in place securely, in a manner that makes it difficult for the driver to remove it. However, the device must also be such that the officer can remove it easily as soon as the officer is convinced that there is no danger.
I contacted 150 Mississippi law enforcement officers and asked each whether he would use a device with the characteristics described above. 149 said that they would, even if they had to purchase it themselves. Every officer stated that they considered an unsecured vehicle door to be a substantial threat to their safety when they approached a stopped vehicle. Some cited specific instances where they believed that fellow officers had been seriously injured or lost their lives after being suddenly hit with a vehicle door. They also pointed out that a suspect secured inside his vehicle cannot run away on foot. The most common comment from these officers was that they needed a way to gain 3 to 5 seconds during the period when a suspect began taking aggressive action, and that this device would provide them with that time. The officers also concluded that eliminating the suspect's ability to escape or take aggressive action with the car door, without diminishing the officer's ability to draw her or his weapon, would save officers' lives, perhaps their own.
SUMMARY OF THE INVENTION
The present invention is designed to fill the need described above by providing a means for holding a vehicle door closed without damaging the vehicle. More specifically, the present invention includes a clamping device which is applied to the doorpost of a vehicle through the window, from behind the front door and outside the vehicle. The device is intended for use by law enforcement officers, who would attach it by placing it into the open or partially-open window of the front door, sliding the clamping surfaces around the interior and exterior portions of the vehicle doorpost, and closing the clamp. The user closes the clamp by activating a means for drawing the clamp jaws toward one another and holding them there. The clamp may be released by de-activating the holding mechanism. Finally, the clamping surfaces are constructed of materials that do not scratch or otherwise damage the doorpost or interior window frame surfaces.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates the preferred embodiment of the invention in use protecting a law enforcement officer from a suspect inside a vehicle by clamping the left front door of a vehicle shut.
FIG. 2 is a top, elevation view showing the preferred embodiment of the present invention with the clamping faces fully open.
FIG. 3 is a view taken along B--B of FIG. 2.
FIG. 4 is a view taken along C--C of FIG. 3.
FIG. 5 illustrates the preferred embodiment with a pivoting mount for the moveable clamp face.
FIG. 6 illustrates the preferred embodiment driven by an electrical motor.
FIG. 7 illustrates the preferred embodiment driven by hand pull.
FIG. 8 illustrates the preferred embodiment driven by spring tension.
FIG. 9 illustrates the preferred embodiment driven by compressed air.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 1, there is shown a police doorpost clamp 100 incorporating the principles of this invention clamped on the doorpost 102 of vehicle 104.
FIGS. 2-4 illustrate a preferred embodiment of the present invention in the fully open position. Police doorpost clamp 100 consists of a first clamp jaw 200 with pad 202, a second clamp jaw 204 with pad 206, clamping bar 208 with padded edge 210, handle 212, user closing means 214, user release means 216, and housing 218 containing internal clamp closing means 220 and internal clamp release means 222. Jaw 200 and housing 218 may be molded from a single piece as illustrated in FIGS. 2-4. Likewise, jaw 204 and bar 208 may be molded from a single piece as illustrated in FIG. 2-4, or jaw 204 may be attached to bar 208 at end 224 of bar 208 as illustrated in FIG. 5. In the preferred embodiment of the present invention, the exposed clamp surfaces, such as the unpadded surface of bar 208 and the surface of housing 218, should be smooth, thereby making it more difficult to grip clamp 100 while it is clamped on doorpost 102. The distance between fixed jaw 200 and moveable jaw 204 is determined by the position of sliding bar 208 with respect to housing 218. Closing means 220 is attached to bar 208, and when used as intended, internal closing means 220 is enabled by user closing means 214, thereby causing bar 208 to pull the inner face of jaw 204 with pad 206 toward the inner face of jaw 200 with pad 202 until vehicle doorpost 102 between jaws 200 and 204 becomes tightly clamped between pads 202 and 206. Internal release means 222 is engaged by user release means 216, thereby disengaging means 220 and unclamping doorpost 102. Clamp 100 may be reset for next use by returning clamp 100 to its fully open position as illustrated in FIGS. 2-4.
The preferred dimensions of the inner clamp jaw faces, padded clamping bar and housing illustrated in FIG. 2-4 are as follows: The inner faces of jaws 200 and 204 may be 2 to 7 inches square and 0.25 to 2 inches thick (5" and 0.5" most preferred). In order to fit a variety of doorpost widths in the range 3 to 6 inches, the distance between jaws 200 and 204 should be at least 7 inches when clamp 100 is open, and the maximum movement of bar 208 should be at least 4 inches. Housing 218 must be of sufficient size to contain internal closing means 220 and to permit clamping bar 208 to move up to at least 4 inches to the left in FIG. 2.
In the preferred embodiment of the present invention illustrated in FIG. 5, moveable clamp jaw 204 is mounted on clamp shaft 500 which is attached to end 224 of bar 208. As shown in FIG. 5, shaft 500 extends through clamp shaft hole 502 horizontally through the width of clamp jaw 204 in such a manner that jaw 204 can rotate several degrees in each direction about the axis determined by shaft 500. The purpose of incorporating the pivoting clamp jaw is to increase the contact surface area between pad 206 and sloped doorposts. In the preferred embodiment, the pivot angle is limited by the shape of shaft 500 and shaft hole 502 using means well know to those skilled in the art. This is necessary to ensure that jaw 204 will not be out of position when clamp 100 is applied to doorpost 102.
As described above, in the preferred embodiment of the present invention, the inner faces of jaws 200 and 204 and bar 208 are covered with pads 202, 206 and 210, respectively. One purpose of pads 202 and 206 is to increase the friction between jaws 200 and 204 and doorpost 102, thereby increasing the grip of the present invention on doorpost 102 and securing the door of vehicle 104. Another purpose of pads 202, 206 and 210 is to protect doorpost 102 and vehicle 104 from being scratched by the surfaces of jaws 200 and 204 and bar 208, respectively. Therefore, the pads should cover their respective inner clamp jaw faces sufficiently to protect doorpost 102 from scratches and to insure adequate contact between surfaces for strong clamping action on doorpost 102. These pads may be rubber, or any sufficiently elastic, durable material with a high coefficient of friction. As described more fully below, the thickness and elasticity of pads 202 and 206 should be such that means 220 can provide strong clamping action on doorpost 102. In the preferred embodiment of the present invention, pads 202 and 206 may be replaced when worn out.
As shown in FIG. 6, internal closing means 220 may be bar 208 attached by belt 600 wound to pulley 602 driven through drive 604 by servomotor 606, which may be powered by battery 608. Said battery 608 may be of the disposable or rechargeable, conventional, or solar type, and should be continuously monitored with condition of charge displayed by display 610 by means well known in the art. Said servomotor may be capable of breaking automatically and holding when a threshold feedback load is applied. In the case where means 220 comprises a servomotor-driven pulley and belt, user closing means 214 may be toggle switch 612 which is in electrical communication 614 with motor 606, and thereby turns motor 606 on in the "on" position and off in the "off" position. If motor 606 is of the type that automatically breaks and holds when a feedback threshold load occurs, the desired threshold is set in the preferred embodiment of the invention, and the user merely turns switch 612 to "on" to clamp doorpost 102, and to "off" to release clamp 100 from doorpost 102. On the other hand, if motor 606 is not of the type that automatically breaks and holds, brake 616 and clutch 618 should be present, with brake 616 in electrical communication with switch 612 and activated electronically when switch 612 is in said "off" position. In this embodiment, the user must turn switch 612 first to "on" and thence to "off" to cause the clamping action of clamp 100 on doorpost 102. Internal clamp release means 222 may be clutch 618, which may release pulley 602 from drive 604 or belt 600 from pulley 602. In either case, user release means 216 is clutch release shaft 620 and clutch trigger 622, which are connected to clutch 618 and thereby engage and disengage clutch 618 by means well know in the art when trigger 622 is operated by the user. User release means 216 should also be in electrical communication with and disengage brake 616. Thus, in this embodiment of the present invention, clutch 618 is engaged before motor 606 is "on," continues to be engaged while clamp 100 is in place on doorpost 102, but is disengaged by user release means 216 when the user is ready to remove clamp 100 from doorpost 102. Brake 616, on the other hand, is not engaged until motor 606 is "off," and is disengaged by user release means 216.
EXAMPLE 1
A series 80000 pancake stepper motor (Haydon Switch and Instrument, Inc., Waterbury, Conn.) or a facsimile thereof could be used as servomotor 606. The 80000 series motor has a maximum diameter of 3.15" and is 3/8" thick. This motor uses U.S. Pat. No. 4,714,853, in which the coils are mounted inside one another and the magnetic rotor is a ring that is located between the coils. The 80240-12, for example, has an operating voltage of 12 v, a power consumption of 6 watts, and weighs 7.75 oz.
EXAMPLE 2
The Milwaukee #48-11-0200 battery pack or a facsimile thereof may be used as battery 608. The Milwaukee #48-59-0166 battery charger may be used to recharge the #48-11-0200 battery pack, usually in less than an hour.
Alternatively, internal clamp closing means 220 may be gear wheels and connecting gear shafts. In the preferred embodiment of the present invention as shown in FIG. 7, means 220 comprises a first toothed gear shaft, 700, a top gear wheel 702, a bottom gear wheel 704, and a second gear shaft 706 with teeth 708, which is incorporated in sliding bar 208. Wheel 702 is affixed to wheel 704 with common center points, and the teeth on wheel 702 mesh the teeth on shaft 700 and the teeth on wheel 704 match teeth 708. The ratios of the diameters of said top wheel 702 and said bottom wheel 704 should be in the range of the desired linear distance for movement of handle 212 divided by the desired linear distance for movement of jaw 204. User closing means 214 comprises handle 212 and handle shaft 710, which connects shaft 700 to handle 212. When handle 212 is pulled away from housing 218, shaft 700 causes wheel 702 to rotate, which causes wheel 704 rotate at the same number of rotations per minute as wheel 702, which causes shaft 706 and sliding bar 208 to move to the left, thereby causing clamp jaw 204 and pad 206 to move toward jaw 200 and pad 202 until vehicle doorpost 102 is tightly clamped shut. The distance jaw 204 and pad 206 move is determined by the ratio of the radii of wheel 704 to wheel 702 times the distance handle 212 is moved away from housing 218 until pads 202 and 206 clamp doorpost 102 closed:
D(jaw 204)=D(handle 212)×radius(wheel 704)/radius(wheel 702) whereas the clamping force, F(jaw 204) resulting from user applied force, F(handle 212) is:
F(jaw 204)=F(handle 212)×radius(wheel 702)/radius wheel 704).
If the applied force is a gripping force supplied by the user, the radii of wheels 702 and 704 must be selected to accommodate normal user gripping distances and forces.
EXAMPLE 3
If the user gripping distance is 2" and jaw 204 might have to close as much as 4", the radius of wheel 702 should be one half the radius of wheel 704, but the clamping force applied by the user will be only half the force of her or his grip.
On the other hand, where the applied force is a pulling force supplied by the user, the ratio of the radii of wheels 702 and 704 and the resulting clamping force are constrained by the distance jaw 204 might be required to move and the user pulling distance, which can be substantially greater than her or his gripping distance.
EXAMPLE 4
If the user pulling distance is 8" and jaw 204 might have to close as much as 4", the radius of wheel 702 may be twice the radius of wheel 704, and the clamping force applied by the user will be twice the force of her or his pull.
Since such pulling force is also substantially greater than said gripping force, the preferred embodiment of the present invention uses the pulling handle mechanism in user release means 216.
In the case where means 220 includes shaft 706 with teeth 708, internal clamp release means 222 may be angle rod 712 held against teeth 708 of shaft 706 by one or more springs 714, until released by user release means 216. As shown in FIG. 7, the angled end, 716, of rod 712 is angled to the left, which, by means well known to those skilled in the art, permits teeth 708 of shaft 706 to move to the left, but prevents shaft 706 from moving to the right unless end 716 of rod 712 is withdrawn from teeth 708 of shaft 706. Release means 216 comprises a grasping means 718 at the unangled end 720 of rod 712 which may be used to overcome the tension of springs 714, thereby withdrawing end 716 of rod 712 from teeth 708 of shaft 706, releasing pad 206 from doorpost 102 and permitting clamp 100 to be reset to its fully open position for next use.
In the preferred embodiment of the present invention using the internal release means illustrated in FIG. 7, teeth 708 on shaft 706 should be closely spaced. This is because end 716 of rod 712 does not position shaft 706 continuously, and the final clamping position of face 204 is a discrete set of points D(teeth 708) apart. Adequate clamping action for clamp 100 is achieved by selecting the pitch of teeth 708 to be sufficiently small that the elasticity of pads 202 and 206 accommodates at least one half of D(teeth 708) without substantial loss in F(jaw 204).
EXAMPLE 5
If the pitch of teeth 708 is 16/inch, then each pad must accommodate 1/32" without substantial loss of clamping force on doorpost 102.
Alternatively, internal clamp closing means 220 may be a spring. In the embodiment of the present invention shown in FIG. 8, means 220 comprises bar 208 attached by toothed shaft 800 to spring 802. In the embodiment illustrated in FIG. 8, shaft 800 may be incorporated into bar 208. The maximum tension on spring 802 is set when clamp 100 is reset in the fully open position, and held by angle rod 804, which is angled to the right at end 806 where it engages the teeth of shaft 800. In the case where means 220 comprises such a spring-pulled shaft, user closing means 214 may be grasping means 808 attached to the unangled end 810 of rod 804. When the user pulls grasping means 808, end 806 is disengaged from the teeth of shaft 800, and the tension in spring 802 is released, thereby pulling bar 208 and clamp jaw 204 to the left, and closing clamp 100 on doorpost 102. Clamp 100 may be held closed or released by a variety of means, including the internal clamp release means and the user release means disclosed in connection with FIG. 7. Alternatively, as illustrated in FIG. 8, clamp 100 may be held closed by sufficient residual tension in spring 802, and reopened by cranking rachet 812, using handle 814, or another mechanism well known in the art, to reset full tension on spring 802.
Alternatively, internal clamp closing means 220 may be a chambered piston driven by compressed air and connection piston rod and shaft. In the preferred embodiment of the present invention as shown in FIG. 9, means 220 comprises bar 208 attached by piston rod 900 to piston 902 which may be driven to the left in FIG. 9 by releasing compressed air stored in compressed air chamber 904 through valve 906 into a second chamber 908 which contains piston 902. Like shaft 706 in FIG. 706, rod 900 may be toothed and incorporated in bar 208 or it may be connected to bar 208 by a toothed shaft. Using pump 910, the air in chamber 904 may be compressed before using clamp 100 by means well known in the art. For example, pump 910 may be similar to air-compressing devices used in air rifles. In the case where means 220 comprises such a air-driven piston, user closing means 214 may be valve trigger 912 connected to valve 914 by valve shaft 916. Pulling trigger 912 causes valve 906 to open, thereby releasing air into chamber 908 and driving piston 902 to the left. This causes rod 900 to pull bar 208 and clamp jaw 204 to the left, thereby closing clamp 100 on doorpost 102. Clamp 100 may be held closed or released by a variety of means, including the internal clamp release means and the user release means disclosed in connection with FIG. 7.
Alternatively, a small explosive cartridge, or numerous other means that are obvious to those skilled in the art could be used in the present invention.
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A clamp that may be attached to a vehicle door to hold the door closed without damaging the vehicle is described. The device may be used by a police officer to secure the door of the vehicle, thereby preventing the occupants from opening the door suddenly and injuring the officer or fleeing. The mechanism for closing the clamp may be powered by a number of means, including an electrical motor, a hand pull, a spring, compressed air, and the like. The device includes a means for releasing the clamp when the officer no longer has reason to suspect that the occupants will injure him or flee.
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CLAIMING BENEFIT OF PRIOR FILED U.S. APPLICATION
[0001] This application claims the benefit of U.S. Provisional Application Ser. No. 61/132,714 entitled “Loop Prevention Mechanism for the ITU Standard ITU-T G.8032 Ethernet Ring Protection” filed on Jun. 20, 2008 the contents of which are hereby incorporated by reference herein.
TECHNICAL FIELD
[0002] The present invention relates in general to local and metropolitan area networks and, in particular, to a node (bridge, switch, router) that implements a loop prevention mechanism for Ethernet ring protection. In one embodiment, the loop prevention mechanism can enhance the current draft of standard ITU-T G.8032 Ethernet Ring Protection Switching.
BACKGROUND
[0003] The following abbreviations are herewith defined, at least some of which are referred to within the following description of the state-of-the-art and the present invention.
APS Automatic Protection Switching CC Continuity Check CFM Connectivity Fault Management ERP Ethernet Ring Protection ETH Ethernet FDB Forwarding Database IEEE Institute of Electrical and Electronics Engineers ITU International Telecommunication Union LAN Local Area Network MAC Message Authentication Code MAN Metropolitan Area Network NR No Request OAM Operation, Administration and Maintenance RB RPL Blocked RPL Ring Protection Link SF Signal Failure STP Spanning Tree Protocol TTL Time to Live TLV Type Length Value VLAN Virtual Local Area Network WTR Wait to Restore
[0025] Computers are often connected together through a network (e.g., LAN, MAN) that is made up of nodes (bridges, switches, routers) in which it is desirable for data that is being transmitted from one bridge to be constrained to follow a loop-free path. Unfortunately, the previous draft standard of ITU-T G.8032 Ethernet Ring Protection Switching exhibited the possibility for some data loops to be created when old information circulates within the ring. The most critical problem is when old information interpretation allows the creation of a loop of data traffic that may last several minutes. This problem where a data loop can be formed if a node wrongly interprets an old message is demonstrated in an exemplary scenario discussed in detail below with respect to FIGS. 1A-1K (PRIOR ART).
[0026] Prior to describing this exemplary scenario, a brief discussion is provided next to promote an understanding of some of the main terms and concepts associated with the ITU-T G.8032 standard (the contents of which are incorporated by reference herein) that may be relevant to the present discussion. Of course, those people who are skilled in the art will already be well aware of these main terms and concepts commonly associated with the protocol of ITU-T G.8032.
[0027] The ITU-T G.8032 standard's Objectives and Principles are highlighted here:
Use of standard 802 MAC and OAM frames around the ring. Uses standard 802.1Q (and amended Q bridges), but with the xSTP disabled. Ring nodes support standard FDB MAC learning, forwarding, flush behavior and port blocking/unblocking mechanisms. Prevents loops within the ring by blocking one of the links (either a pre-determined link or a failed link). Monitoring of the ETH layer for discovery and identification of SF conditions. Protection and recovery switching within 50 ms for typical rings. Total communication for the protection mechanism should consume a very small percentage of total available bandwidth.
[0035] The ITU-T G.8032 standard's Terms and Concepts are highlighted here:
ERP—The common name for the ITU-T G8032 draft standard. RPL—Link designated by mechanism that is blocked during Idle state to prevent loop on bridged ring. RPL Owner—Node connected to RPL that blocks traffic on RPL during idle state and unblocks during protected state. Link Monitoring—Links of ring are monitored using standard ETH CC OAM messages (CFM). SF—Signal Fail is declared when ETH trail signal fail condition is detected. NR—No Request is declared when there are no outstanding conditions (e.g., SF, etc.) on the node. Ring APS (R-APS) Messages—Protocol messages defined in G.8032 and ITU-T Y.1731 entitled “OAM Functions and Mechanisms for Ethernet Based Networks” (the contents of which are incorporated by reference herein). APS Channel—Ring-wide VLAN used exclusively for transmission of OAM messages including R-APS messages. TLV—Optional information that may be encoded as a type-length-value or a TLV element and used within data communication protocols and particularly within ITU-T Y1731 onto which the ITU-T G.8032 has based its frame format for R-APS. The type and length fields are fixed in size (typically 1-4 bytes), and the value field is of variable size. These fields are used as follows: Type: a numeric code which indicates the kind of field that this part of the message represents. Length: the size of the value field (typically in bytes). Value: variable sized set of bytes which contains data for this part of the message.
[0048] Some of the advantages of using a TLV representation are:
TLV sequences are easily searched using generalized parsing functions. New message elements which are received at an older node can be safely skipped and the rest of the message can be parsed. TLV elements are typically used in a binary format which makes parsing faster and the data smaller.
[0052] The ITU-T G.8032 standard specifies the use of different timers to avoid race conditions and unnecessary switching operations. These timers are highlighted here:
WTR Timer—Used by RPL Owner to verify that the ring has stabilized before blocking the RPL after SF Recovery. The WTR timer may be configured by the operator in 1 minute steps between 5 and 12 minutes; the default value is 5 minutes. Hold-off Timers—Used by underlying ETH layer to filter out intermittent link faults, where faults will only be reported to the ring protection mechanism if this timer expires.
[0055] The ITU-T G.8032 standard's Controlling the Protection Mechanism is highlighted here:
Protection switching triggered by:
Detection/clearing of Signal Failure (SF) by ETH CC OAM. Remote requests over R-APS channel (Y.1731). Expiration of G.8032 timers.
R-APS requests control the communication and states of the ring nodes:
Two basic R-APS messages specified—R-APS(SF) and R-APS(NR). RPL Owner may modify the R-APS(NR) indicating the RPL is blocked—R-APS(NR,RB).
Ring nodes may be in one of two states:
Idle—normal operation, no link/node faults detected in ring.
Protecting—Protection switching in effect after identifying a signal fault.
[0066] The ITU-T G.8032 standard's link failure scenario is highlighted here:
1. Link/node failure is detected by the nodes adjacent to the failure. 2. The nodes adjacent to the failure will block the failed link and report this failure to the ring using R-APS (SF) message. 3. R-APS (SF) message triggers:
RPL Owner unblocks the RPL. All nodes perform FDB flushing.
4. Ring is in protection state. 5. All nodes remain connected in the logical topology.
[0074] The ITU-T G.8032 standard's link failure recovery scenario is highlighted here:
1. When the failed link recovers, the traffic is kept blocked on the nodes adjacent to the recovered link. 2. The nodes adjacent to the recovered link transmit RAPS(NR) message indicating they have no local request present. 3. When the RPL Owner receives RAPS(NR) message it starts the WTR timer. 4. Once the WTR timer expires, RPL Owner blocks RPL and transmits a R-APS (NR, RB) message. 5. Nodes receiving the message perform a FDB Flush and unblock their previously blocked ports. 6. Ring is now returned to Idle state.
[0081] Other useful information: the ERP uses the R-APS messages to manage and coordinate the protection switching. The R-APS messages (which are continuously repeated) and the OAM common fields are well known to those skilled in the art and are defined in ITU-T Y.1731.
[0082] Referring to FIGS. 1A-1K (PRIOR ART), there are illustrated several diagrams of an exemplary network 100 at different steps 1 A- 1 L which are used to help describe how a node (e.g., bridge, switch, router) can wrongly interpret an old message which leads to the formation of an undesirable data loop. The discussion below first describes how the bridge can wrongly interpret an old message which leads to the formation of the undesirable data loop then a discussion is provided to explain the deficiencies of the current ITU-T G.8032 standard which proposes to use a guard timer in an attempt to prevent the formation of the undesirable data loop. The different steps 1 A- 1 K respectively correspond to FIGS. 1A-1K .
[0083] 1 A. Assume the exemplary network 100 has a ring of six nodes that are numbered from 1 to 6 and called node 1 to node 6 , respectively. The node 1 is the RPL owner.
[0084] 1 B. Assume node 1 periodically sends R-APS 1 (NR,RB) messages reflecting its idle state, across the ring (as per standard). Assume node 1 is blocking a port 102 to RPL link 104 to prevent a loop (as per standard). Assume all nodes 1 - 6 are in idle states.
[0085] 1 C. Assume there is a failure 106 on link 108 between node 5 and node 6 .
[0086] 1 D. Node 5 and node 6 respectively block ports 110 and 112 on failed link 108 and send R-APS(SF) messages when they transition from the idle state to the protection state (as per standard).
[0087] 1 E. Assume the link 108 is up again between node 5 and node 6 . Node 5 and node 6 send R-APS(NR) messages and remain in the protection state (as per standard).
[0088] 1 F. Assume the RPL owner (node 1 ) receives the R-APS (SF) message sent by node 5 or node 6 during step 1 D. The RPL owner (node 1 ) unblocks the non failed RPL port 102 and goes from the idle state into the protective state.
[0089] 1 G. Assume the RPL owner (node 1 ) receives a R-APS(NR) message sent from node 5 or node 6 during step 1 E. The RPL owner (node 1 ) starts a WTR 114 and remains in the protective state (as per the standard).
[0090] 1 H. Assume that the WTR 114 expires, the RPL owner (node 1 ) blocks the RPL port 102 again and goes back to the idle state. The RPL owner (node 1 ) periodically sends R-APS 2 (NR,RB) messages.
[0091] 1 I. Node 5 and node 6 receive the R-APS 2 (NR,RB) message from step 1 H, unblock the non failed ports 110 and 112 and transition from the protection state to the idle state (as per standard).
[0092] Steps 1 H and 1 I are the expected sequence of steps but a non-expected sequence of steps 1 J and 1 K could occur after step 1 G which would lead to the undesirable creation of the data loop in the network 100 . The problematical and un-expected sequence of steps 1 J and 1 K are as follows:
[0093] 1 J. The WTR timer 114 is still running at RPL owner (node 1 ).
[0094] 1 K. Node 5 and node 6 receive the R-APS 1 (NR,RB) message from step 1 A, unblock the non-failed ports 110 and 112 and transition from the protection state to the idle state (as per standard).
[0095] Steps 1 J and 1 K are possible if there is a delay in transmitting messages from node 1 to node 5 because of, for example, congestion/queueing or software processing (if trap and forward in software). In this situation, the R-APS 1 (NR,RP) message from step 1 A could still be transiting over the ring while the RPL owner (node 1 ) was already in the protective state. In this case, the RPL owner (node 1 ) would have RPL port 102 forwarding and the nodes 5 and 6 would have their ports 110 and 112 all forwarding at the same time which means there would be an undesirable loop 116 (see FIG. 1K ). Unfortunately, this loop 116 cannot be characterized as “transient” which means its duration is very short probably less than 500 ms. Instead, the loop 116 can last for as long as the WTR timer is configured meaning 10 minutes at worse. Of course, this type of situation should prevented at all cost because TTL is not implemented at layer 2 in the network 100 which means that a layer 2 loop 116 would allow some packets to loop forever.
[0096] The current solution to this problem is described in the ITU-T G.8032 draft standard. The ITU-T G.8032 attempts to solve this problem by configuring and using a guard timer to ignore certain messages that are susceptible to being too old. To clarify the goal of the guard timer, the standard states the following:
[0097] “R-APS messages are continuously repeated with an interval of 5 seconds. This, combined with the R-APS messages forwarding method, in which messages are copied and forwarded at every ring node around the ring, can result in a message corresponding to an old request, which is no longer relevant, being received by ring nodes. The reception of messages with outdated information could result in erroneous interpretation of the existing requests in the ring and lead to erroneous protection switching decisions.
[0098] The guard timer is used to prevent ring nodes from receiving outdated R-APS messages. During the duration of the guard timer, all received R-APS messages are ignored by the ring protection control process. This allows that old messages still circulating on the ring may be ignored. This, however, has the side effect that, during the period of the guard timer, a node will be unaware of new or existing ring requests transmitted from other nodes.
[0099] The period of the guard timer may be configured by the operator in 10 ms steps between 10 ms and 2 seconds, with a default value of 500 ms. This time should be greater than the maximum expected forwarding delay for which one R-APS message circles around the ring.
[0100] The guard timer may be started and stopped. While the guard timer is running the received R-APS Request/State and Status information is not forwarded. If the guard timer is not running, the R-APS Request/State information is forwarded unchanged. “see Section 10.1.5 in ITU-T G.8032 (June 2008).
[0101] Also, the guard timer is started on detection of a “local clear SF” meaning that the failure condition has been detected before (link down for example) and is now not happening anymore and is therefore cleared. Thus, when this guard timer is applied to present scenario this means that the user will have to configure the guard timer by estimating how long at worse, a frame can be delayed, so that all previous R-APS(NR,RB) messages are not wrongly interpreted which if done can lead to the creation of some very long lasting loops 116 . The guard timer solution is inadequate for the following reasons (for example):
[0102] 1. A node may discard a valid message, and this may create other kinds of problems. For example, the discarding of an R-APS message carrying a flush (in its status field) can create a loss of connectivity between elements connected through this ring, since the node does not react to this important instruction allowing flooding and addresses to be relearned. This loss of connectivity may last 5 seconds assuming that this is the chosen interval for sending the R-APS message.
[0103] 2. The guard timer relies on the user setup (because the guard timer is not mandated by the ITU-T G8032 draft standard) of a timer therefore the user needs to understand this kind of complex problem. Then, even if the user configures the guard timer, it can still be too short and the problem can still arise and if it is too long some valid frames can be lost.
[0104] Accordingly, there has been and still is a need to address the aforementioned shortcomings and other shortcomings associated with the creation of undesirable loops and the proposed guard timer. These needs and other needs are satisfied by the present invention.
SUMMARY
[0105] In one aspect, the present invention provides a method implemented by a node (non RPL owner node) for preventing a creation of a loop within a ring of a network. The method includes the steps of: (a) keeping track of a failure number in the ring of the network; (b) incrementing the kept track failure number when detecting a local failure; (c) updating the kept track failure number with a failure number from a message received from another node in the ring if the failure number in the received message is larger than the kept track failure number; and (d) discarding, while in a protection state, a message received from a ring protection link owner node if the failure number in the received message is less than the kept track failure number, wherein the discarding of the received message from the ring protection link owner node prevents any possible interpretation of old information within the received information which causes the creation of the loop within the ring of the network.
[0106] In another aspect, the present invention provides a method implemented by a node (RPL owner node) for preventing a creation of a loop within a ring of a network. The method includes the steps of: (a) keeping track of a failure number in the ring of the network; (b) incrementing the kept track failure number when detecting a local failure; and (c) updating the kept failure number with any failure number in a message received from another node that transitioned from an idle state to a protection state.
[0107] In yet another aspect, the present invention provides a non-ring protection link owner node including: (a) a processor; and (b) a memory that stores processor-executable instructions where the processor interfaces with the memory and executes the processor-executable instructions to enable the following: (i) keep track of a failure number in the ring of the network; (ii) increment the kept track failure number when detecting a local failure; (iii) update the kept track failure number with a failure number from a message received from another node in the ring if the failure number in the received message is larger than the kept track failure number; and (iv) discard, while in a protection state, a message received from a ring protection link owner node if the failure number in the received message is less than the kept track failure number, wherein the discarding of the received message from the ring protection link owner node prevents any possible interpretation of old information within the received message which causes the creation of the loop within the ring of the network.
[0108] In still yet another aspect, the present invention provides a non-ring protection link owner node including: (a) a processor; and (b) a memory that stores processor-executable instructions where the processor interfaces with the memory and executes the processor-executable instructions to enable the following: (i) keep track of a failure number in the ring of the network; (ii) increment the kept track failure number when detecting a local failure; and (iii) update the kept failure number with any failure number in a message received from another node that transitioned from an idle state to a protection state.
[0109] In yet another aspect, the present invention provides a network that includes: (a) a non-ring protection link owner node that has a processor and a memory that stores processor-executable instructions where the processor interfaces with the memory and executes the processor-executable instructions to enable the following: (i) keep track of a failure number in a ring; (ii) increment the kept track failure number when detecting a local failure; (iii) update the kept track failure number with a failure number from a message received from another node in the ring if the failure number in the received message is larger than the kept track failure number; and (iv) discard, while in a protection state, a message received from a ring protection link owner node if the failure number in the received message is less than the kept track failure number, wherein the discarding of the received message from the ring protection link owner node prevents any possible interpretation of old information within the received message which causes the creation of the loop within the ring of the network; and (b) the ring protection link owner node includes a processor and a memory that stores processor-executable instructions where the processor interfaces with the memory and executes the processor-executable instructions to enable the following: (i) keep track of the failure number in the ring; (ii) increment the kept track failure number when detecting a local failure; and (iii) update the kept failure number with any failure number in a message received from one of the non-ring protection link owner nodes that transitioned from an idle state to a protection state.
[0110] Additional aspects of the invention will be set forth, in part, in the detailed description, figures and any claims which follow, and in part will be derived from the detailed description, or can be learned by practice of the invention. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention as disclosed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0111] A more complete understanding of the present invention may be obtained by reference to the following detailed description when taken in conjunction with the accompanying drawings wherein:
[0112] FIGS. 1A-1K (PRIOR ART) are several diagrams of an exemplary traditional network at different times which are used to help describe how a node (e.g., bridge, switch, router) can wrongly interpret an old message which can lead to the problematic formation of an undesirable data loop;
[0113] FIGS. 2A-2L , are several diagrams of an exemplary network at different times which are used to help describe how a node (e.g., bridge, switch, router) can address the aforementioned loop problem when there is one link failure in accordance with an embodiment of the present invention; and
[0114] FIGS. 3A-3L , are several diagrams of an exemplary network at different times which are used to help describe how a node (e.g., bridge, switch, router) can address the aforementioned loop problem when there are multiple link failures in accordance with an embodiment of the present invention.
DETAILED DESCRIPTION
[0115] In the present invention, the failure detecting node and RPL owner are configured to keep track of new information namely the number of the latest failure in the ring. This new information can be added as a new TLV in the R-APS (SF) message, the R-APS(NR) message and the R-APS(NR,RB) message. In fact, the new information can be added as a new TLV in all messages to simplify coding and to allow for future enhancements even though these messages may or may not be used. The use of the TLV to contain this information also has an advantage of allowing the protocol to be compatible with newer extensions, since when the TLV is not supported by an older protocol version or by some other vendor's equipment it will be ignored by the older protocol or the other vendor's equipment. Here are the principles of operation of the proposed extension to the ITU-T G8032 standard:
All nodes (RPL owner and not RPL owner) add a new TLV with a failure number to all the sent R-APS messages. Any node shall keep track of a failure number that starts at 0 at node startup in software. Any node detecting a local failure shall increment its own current failure number. Any non RPL owner node in the protection state shall ignore any R-APS(NR,RB) message if the failure number in the message is strictly inferior than its own. This is to make sure to avoid interpreting old information and causing an undesirable loop (see FIGS. 1J and 1K ). Any non RPL owner node shall update its own failure number with the failure number from any received R-APS message if the failure number in the newly received R-APS message is strictly superior than its own. This is to make sure to have each node using the same biggest possible failure number. The RPL owner node shall update its own failure number with any failure number in a received R-APS(SF) message, if the failure number in the received R-APS(SF) message is strictly superior than its own.
[0122] Referring to FIGS. 2A-2L , there are illustrated several diagrams of an exemplary network 200 at different steps 2 A- 2 L which are used to help describe how a node (e.g., bridge, switch, router) can address the aforementioned loop problem when there is a single link failure in accordance with an embodiment of the present invention. The different steps 2 A- 2 L respectively correspond to FIGS. 2A-2L .
[0123] 2 A. Assume the exemplary network 200 has a ring of six enhanced nodes that are numbered from 1 to 6 and called node 1 to node 6 , respectively. The node 1 is the RPL owner. The enhanced nodes 1 - 6 each have their own processor 202 and a memory 204 that stores processor-executable instructions where the processor 202 interfaces with the memory 204 and executes the processor-executable instructions to implement as needed the aforementioned six principles of operation 206 for extending the protocol of the ITU-T G.8032 standard in accordance with the present invention.
[0124] 2 B. Assume node 1 periodically sends R-APS 1 (NR,RB) messages reflecting its idle state, across the ring (as per standard), plus a new TLV carrying the failure number, set to “0” since no failure has been seen yet. Assume node 1 is blocking a port 208 to RPL link 210 to prevent a loop (as per standard). Assume all of the nodes 1 - 6 are in idle states.
[0125] 2 C. Assume there is a failure 212 on link 214 between node 5 and node 6 .
[0126] 2 D. Node 5 and node 6 respectively block ports 216 and 218 on failed link 214 and send R-APS(SF) messages when they transition from the idle state to the protection state (as per standard). In addition, the R-APS(SF) messages have a new TLV carrying the failure number, set to “1” since a failure has been detected. The nodes 5 and 6 also increment their own failure number to “1”.
[0127] 2 E. Assume the link 214 is up again between node 5 and node 6 . Node 5 and node 6 send R-APS(NR) messages and remain in the protection state (as per standard). In addition, the R-APS(NR) messages have a new TLV carrying the failure number, set to “1” since a failure has been detected.
[0128] 2 F. Assume the RPL owner (node 1 ) receives the R-APS (SF) message with the TLV carrying the failure number “1” that was sent by node 5 or node 6 during step 2 D. The RPL owner (node 1 ) unblocks the non failed RPL port 208 and goes from the idle state into the protective state. The RPL owner (node 1 ) also sets its own failure number to “1”.
[0129] 2 G. Assume the RPL owner (node 1 ) receives R-APS(NR) from node 5 or node 6 during step 2 E. The RPL owner (node 1 ) starts a WTR 220 and remains in the protective state (as per the standard).
[0130] 2 H. The WTR timer 220 is still running at the RPL owner (node 1 ).
[0131] 2 I. Node 5 and node 6 both receive the R-APS 1 (NR,RB) message from step 2 A. The R-APS 1 (NR,RB) message is discarded and a loop is avoided because the message has a failure number “0” while the current node failure number is “1” (no need of using a guard timer) (compare to FIGS. 1J and 1K ).
[0132] Steps 2 H and 2 I are the un-expected sequence of steps due to the delay in node 5 and node 6 receiving the R-APS 1 (NR,RB) message from step 2 A. As can be seen, there is no creation of an undesirable loop nor was there a need to use a guard timer. The following discussion describes the expected sequence of steps 2 J- 2 L that should occur after step 2 G. The steps 2 J- 2 L are as follows:
[0133] 2 J. Assume that the WTR 220 expires, the RPL owner (node 1 ) blocks the RPL port 208 again and goes back to the idle state. The RPL owner (node 1 ) periodically sends R-APS 2 (NR,RB) across the ring reflecting its idle state (as per standard), plus the R-APS 2 (NR,RB) has a new TLV carrying the failure number set to “1” since this failure has been seen.
[0134] 2 K. Node 5 and node 6 receive the R-APS 2 (NR,RB) messages from step 2 J. Node 5 and node 6 do not ignore the R-APS 2 (NR,RB) messages because they have the TLVs with the failure number of “1” and the current node failure number is “1” (no need of using a guard timer). Thus, node 5 and node 6 unblock the non failed ports 216 and 218 and transition from the protection state to the idle state.
[0135] 2 L. All nodes 1 - 6 in the “idle” state update their current failure number to “1” which is the same as in the TLV of the R-APS 2 (NR,RB) messages.
[0136] The principles of operation 206 for the proposed extension to the ITU-T G8032 standard in accordance with the present invention also work in case multiple failures occur in the ring of the network 200 . Referring to FIGS. 3A-3L , there are illustrated several diagrams of an exemplary network 300 at different steps 3 A- 3 L which are used to help describe how a node (e.g., bridge, switch, router) can address the aforementioned loop problem when there are multiple link failures in accordance with an embodiment of the present invention. The different steps 3 A- 3 L respectively correspond to FIGS. 3A-3L .
[0137] 3 A. Assume the exemplary network 300 has a ring of six enhanced nodes that are numbered from 1 to 6 and called node 1 to node 6 , respectively. The node 1 is the RPL owner. The enhanced nodes 1 - 6 each have their own processor 302 and a memory 304 that stores processor-executable instructions where the processor 302 interfaces with the memory 304 and executes the processor-executable instructions to implement as needed the aforementioned six principles of operation 306 for extending the protocol of the ITU-T G.8032 standard in accordance with the present invention.
[0138] 3 B. Assume node 1 periodically sends R-APS 1 (NR,RB) messages reflecting its idle state, across the ring (as per standard), plus a new TLV carrying the failure number, set to “0” since no failure has been seen yet. Assume node 1 is blocking a port 308 to RPL link 310 to prevent a loop (as per standard). Assume all of the nodes 1 - 6 are in idle states.
[0139] 3 C. Assume there is a failure 312 on link 314 between node 2 and node 3 and a failure 316 on link 318 between node 5 and node 6 .
[0140] 3 D. Node 2 and node 3 respectively block ports 320 and 322 on failed link 314 and send R-APS(SF) messages when they transition from the idle state to the protection state (as per standard). In addition, the R-APS(SF) messages have a new TLV carrying the failure number, set to “1” since a failure has been detected. Likewise, node 5 and node 6 respectively block ports 324 and 326 on failed link 318 and send R-APS(SF) messages when they transition from the idle state to the protection state (as per standard). In addition, these R-APS(SF) messages have a new TLV carrying the failure number, set to “1” since a failure has been detected. The nodes 2 , 3 , 5 and 6 also increment their own failure number to 1.
[0141] 3 E. Assume the link 314 is up again between node 2 and node 3 . Node 2 and node 3 send R-APS(NR) messages and remain in the protection state (as per standard). In addition, these R-APS(NR) messages have a new TLV carrying the failure number, set to “1” since a failure has been detected. Likewise, assume the link 318 is up again between node 5 and node 6 . Node 5 and node 6 send R-APS(NR) messages and remain in the protection state (as per standard). In addition, these R-APS(NR) messages have a new TLV carrying the failure number, set to “1” since a failure has been detected. From this state, nodes 2 , 3 , 5 and 6 receiving a R-ASP(NR,RB) will perform the following action (among other not related to present discussion) to “unblock both ports” (as per standard).
[0142] 3 F. Assume the RPL owner (node 1 ) receives the R-APS (SF) message with the TLV carrying the failure number “1” that was sent by node 5 or node 6 during step 3 D. The RPL owner (node 1 ) unblocks the non failed RPL port 308 and goes from the idle state into the protective state. The RPL owner (node 1 ) also sets its own failure number to 1. The RPL owner (node 1 ) would perform the same action if it received the R-APS (SF) message with the TLV carrying the failure number “1” that was sent by node 2 or node 3 during step 3 D.
[0143] 3 G. Assume the RPL owner (node 1 ) receives R-APS(NR) from node 5 or node 6 during step 3 E. The RPL owner (node 1 ) starts a WTR 328 and remains in the protective state (as per the standard). The RPL owner (node 1 ) would perform the same action if it received the R-APS (NR) message with the TLV carrying the failure number “1” that was sent by node 2 or node 3 during step 3 E.
[0144] 3 H. The WTR timer 328 is still running at the RPL owner (node 1 ).
[0145] 3 I. Node 5 and node 6 both receive the R-APS 1 (NR,RB) message from step A. The R-APS 1 (NR,RB) message is discarded and a loop is avoided because the message has a failure number “0” while the current node failure number is “1” (no need of using a guard timer) (compare to FIGS. 1J and 1K ). Node 2 and node 3 would perform in the same manner.
[0146] Steps 3 H and 3 I are the un-expected sequence of steps due to the delay in node 5 and node 6 (or node 2 and 3 ) receiving the R-APS 1 (NR,RB) message from step 3 A. As can be seen, there is no creation of an undesirable loop nor was there a need to use a guard timer. The following discussion describes the expected sequence of steps 3 J- 3 L that should occur after step 3 G. The steps 3 J- 3 L are as follows:
[0147] 3 J. Assume that the WTR 220 expires, the RPL owner (node 1 ) blocks the RPL port 308 again and goes back to the idle state. The RPL owner (node 1 ) periodically sends R-APS 2 (NR,RB) across the ring reflecting its idle state (as per standard), plus the R-APS 2 (NR,RB) has a new TLV carrying the failure number set to “1” since this failure has been seen.
[0148] 3 K. Node 5 and node 6 receive the R-APS 2 (NR,RB) messages from step 3 J. Node 5 and node 6 do not ignore the R-APS 2 (NR,RB) messages because they have the TLVs with the failure number of “1” and the current node failure number is “1” (no need of using a guard timer). Thus, node 5 and node 6 unblock the non failed ports 324 and 326 and transition from the protection state to the idle state. Node 2 and node 3 perform in the same manner and unblock the non failed ports 320 and 322 and transition from the protection state to the idle state.
[0149] 3 L. All nodes 1 - 6 in the “idle” state update their current failure number to “1” which is the same as in the TLV of the R-APS 2 (NR,RB) messages.
[0150] How to loop from the maximum failure number to 0 again gracefully while still allowing the enhancement to the protocol to work has not yet been specified. One possible solution could involve having the RPL node (node 1 ) resetting the failure number on all nodes through a specific new TLV just before reaching this maximum failure number. As can be seen, the present invention is relatively simple to implement, transparent to the user, and will always avoid the creation of the undesirable loop.
[0151] Although multiple embodiments of the present invention have been illustrated in the accompanying Drawings and described in the foregoing Detailed Description, it should be understood that the present invention is not limited to the disclosed embodiments, but is capable of numerous rearrangements, modifications and substitutions without departing from the invention as set forth and defined by the following claims.
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A node (bridge, switch, router) and method are described herein that implement a loop prevention mechanism for Ethernet ring protection. In one embodiment, the loop prevention mechanism can enhance the current draft of the standard ITU-T G.8032 Ethernet Ring Protection Switching.
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BACKGROUND
Prior attempts that are presently known to have been disclosed in the field of this invention may be seen in U.S. Pat. No. 2,222,762. It was there intended that hollow bodies adapted for use as pressure vessels be produced from tubular metallic bodies by expanding the walls of the bodies to form a series of enlarged zones, such as spheroids, spaced by parts of the initial tube.
While this is a method of mass production, expensive control measures are required in order that the vessel walls have the appropriate thickness distribution. Otherwise considerably lower pressure resistivity than that available from optimal use of the material will result.
Other attempts at low cost production of cylindrical (metal) pressure vessels that have been noticed in the prior art include the U.S. Pat. No. 2,386,246. In this teaching it is desired to take two cylindrical shells each with one end closed and weld them together at their open ends. Thereafter heat is applied to the welded ends which are spun to a neck portion. This action thickens the closure and neck regions.
This patent teaches to apply a compressive axial force to thicken the neck. The purpose of the present invention is to cause a thinning as the radius is decreased.
In contrast to these known prior art attempts at obtaining metal containers this invention permits one to simplify the manufacture by taking a tubing of long length and doing identical, but optionally simultaneous, operations at a large number of stations. The stations, or areas, as general rule, extend for a length that is approximately equivalent to the diameter of the metal tube; and they are spaced apart a distance equivalent to several diameters. It is also intended to apply local tension to these areas. To avoid subsequent internal cleaning costs to remove oxides which form at elevated temperature if the metal is exposed to air, one may fill the tube with an inert gas such as argon or draw a vacuum to remove the air. The use of a long tube makes possible the forming of 2 necks at each station simultaneously.
This invention for the first time makes it possible to control the resulting thickness and associated radius distribution whereby a quality pressure vessel can be obtained. This control is based on the plasticity relations which apply for the given material as a function of temperature.
One may well attempt, upon an understanding of the present invention from the following description, to view this as an extension of glass forming techniques to the art of metal working. The differences are described below. The forming of glass is done when it is nearly molten, and it cannot support its own weight. A glass tube is sealed by relying on surface tension to draw the open end together. Glass vessels, made by somewhat similar means, do not and are not required to conform to the thickness requirements in a high quality pressure vessel. Finally, the use of constant strain-rate, stress-strain data is not taught in the fabrication of glass pressure vessels regardless of whether they are of appropriate high performance thickness distribution.
In conclusion then this invention has found two applications where it has filled a long standing need. One is in bringing to the art an economic manufacture of high performance pressure vessels; and the second is in bringing to the art the economic manufacture of low weight collapse resistant pressure vessels. Recently still a third possibility for this invention is in the improvement of the manufacture of a manifolded string of pressure vessels whereby one can have a far greater number of vessels with integral manifolds in a space than heretofore possible due to number of attachments, etc.
DRAWING DESCRIPTION
FIG. 1 is a partial cross sectional view of a metal tube showing a work station thereabout;
FIG. 2 is a partial cross section of an intermediate length of tube;
FIG. 2A is a graphical stress-strain illustration;
FIG. 3 is a side view of a multistation apparatus in accordance with this invention;
FIG. 4 is an end view of the apparatus of FIG. 3;
FIG. 5 is a side view of the apparatus of FIG. 3 working to neck down areas of a tube;
FIG. 6 is a partial cross sectional view of a metal tube showing an alternative work station thereabout; and
FIG. 7 is a partial cross-section of an intermediate length of tube prepared for processing per this invention.
DETAILED DESCRIPTION
With particular regard to FIG. 1 there is shown a tube 10 on which are placed split friction rings 12, 14. Clamps 20 and 22 are placed over the rings and secured, as by bolts 24 and 26, respectively, to lock rings 12 and 14 to tube 10.
As seen in FIG. 1 an actuator assembly is fitted by rails 28 and 30 to each clamped ring. The actuator assembly includes semicircular brackets 32 and 34 connected by hydraulic actuators 36 and 38 and by a rod 40 that is slidably mounted by holes 42 and 44 in rings 32 and 34.
An electrical coil heater 46 is mounted by a sleeve 48 to be centered between rings 32 and 34 by springs 50 and 52. This type of heater mounting will insure centralization of the heat as the rings 12 and 14 are moved away from each other as by actuators 36 and 38.
With such apparatus tube 10 is heated locally over a length approximately one diameter long at one or a series of stations, such as the one shown by FIG. 1, many diameters apart.
The heated zones are caused to shrink in diameter and thickness as a result of inelastic elongation of the heated zone. The port 55 leads to a vacuum chamber or to an inert gas such as argon. It is to be understood that the other end of the tube 10 may be closed or could be connected to the same vacuum or inert gas source. Actuators 36 and 38 create longitudinal strain in tube 10 creating the structure shown by FIG. 3 as explained below. If the heated zone were very long, substantially the entire length would be of constant reduced radius and thickness between the held ends. However since the portions to either side of the heating means are cold and strong they cannot contract and the shape of FIG. 2, (hour-glass) will be produced.
As seen in FIG. 2 the radius (R) of the tube is to the thickness (t) in the unworked state as the radius (R 1 ) is to the thickness (t 1 ) in the hour-glassed portion. In order to keep these factors in proportion it is necessary, at a selected temperature, never to exceed the material's ultimate strength associated with a given strain rate. More specifically with reference to the graphical illustration of FIG. 2A the strain used, 11, is less than the maximum strain, 13, for the material. It is important to control the process in accordance with the strain developed in that this varies more controllably than stress, as the curve 15 shows.
If necessary to increase the available strain capability of the particular material the strained zone is reheated to anneal it. The cycle can be repeated as often as required to develop the desired reduction in diameter and thickness in the hour glass region.
With regard now to FIG. 3 there is shown in greater detail how this invention contemplates gang forming operations. There is a plurality of friction blocks 112, 114, 116 and 118 affixed to each other to frictionally clamp on a tube 110 at locations that allow a tube length therebetween of at least one diameter.
As seen in FIG. 4 bolts 100 and 101 install the blocks, which are semicircular halves 102 and 103, to each other and to tube 110.
A scissors link means 104 joins blocks 112, 114, 116 and 118 together and a pair of actuators 136 and 138 are connected in this linkage to operate same. A plurality of heaters 146, 147 and 148 are operatively located between the blocks as aforesaid. These could be electric radiant or induction heating coils, as in FIG. 1, or oxyacetylene manifolds, and temperature monitoring could be by thermocouple or by fiber optic means, not shown.
The tube 110 would be end supported, as in FIG. 1 and on steady rests (not shown) along the length.
A hydraulic system is connected to actuators 136 and 138 to cause the scissors link means to apply the same longitudinal strain on the tube walls between the blocks 112 and 114; 114 and 116; 116 and 118. At the same time heaters 146, 147 and 148 apply localized heat that is the greatest intermediate the blocks. The heaters are mounted as by telescoping rods 152 and 154 from pins 150 FIG. 5 and hence will stay in the proper location. Prior to this operation a vacuum has been pulled within tube 110 and a metered supply of argon has been allowed to flow, as necessary, through tube 110. As noted, this prevents oxide formations inside tube 110 whereby cleaning, after forming, of the interior is not necessary.
If desired, a cooling manifold 16 (see FIG. 1) is located to direct a cooling fluid such as a mist of argon droplets in argon or nitrogen droplets in nitrogen along the direction of arrows 18 to each side of the heater 46 to limit the heated area to that desired under the heater.
The next operation would be to cut the tube into finite lengths in the region of reduced diameter. This produces a vessel having two necked down ends. It is necessary to cold work the ends to return some cross sectional thickness thereto so that threads may be machined on, or rolled therein, for closure caps (not shown) without adversely affecting the strength.
Another application of this invention is for manufacturing low weight collapse resistant pressure vessels by a process using the apparatus shown by FIG. 6. There the tube 156 is provided with a plurality of rings 158 that are located at predetermined intervals by cylindrical springs, such as springs 160 and 162 having surfaces 164 and 166. Collars 168, 170 and 172 are fastened to a rod 174 at selected intervals to provide abutments for the springs. Actually surfaces 160, 162 releasably hold rings 158 among collars 168, 170 abd 172 so as to permit upon completion of the forming of tube 156 the removal of rod 174 and springs 160 and 162 as well as removal of collars 168, 170 and 172.
In operation rings 176 and 178 are clamped to tube 156 about the area of rings 158 therein. Actuators 180 and 182 then apply tensile force to the region 184 of the tube. This could be by pulling on the ends of tube 156 rather than over some intermediate length. In the foregoing embodiment the rings 158 with rings 176 and 178 limit the loaded length to region 184 of the tube 156. Region 184 will begin to thin its wall thickness and its external diameter without rupture so long as the load is applied at a strain rate so that the ultimate strength for the material of tube 156 will not be exceeded. A repeated stretch and anneal operation may be required to obtain the desired hour-glass shape.
The rings 158 could be placed to be a distance from one another equal to the tube diameter or at a lesser or greater distance. The spacing permits manufacture of one or a series of toroidal segments that carry external pressure between rings in a suspension bridge fashion: i.e. the region 184 will be decreased in diameter as tube 156 stretches in the same manner as that shown for the heat and load process by FIG. 2. The region 184 will have its walls between the rings 158 loaded in tension whereby it will be possible to use the structure to withstand longitudinal stress close to the yield point of the material. Also the rings 158 will carry the transverse component of the wall load. Actually the key to formation of the walls, as aforesaid, is that the walls of tube 156 be permitted to buckle hoopwise with the pressure load being carried along the meridian direction.
The degree of hour-glassing required for this application is much less than for the high performance pressure vessels.
As seen in FIG. 7 the rings could be eliminated in cold working a tube 156' by reducing the cross sectional wall thickness thereof in an area 186 between the devices to apply tensile force, as aforesaid. In this regard it has been found that one must take into the yield and ultimate strength of the material and operate within the range between these known limits. Also the forming is more readily accomplished with a material which exhibits a large difference between yield and ultimate strengths.
As various changes may be made in the form, construction and arrangement of the parts in achieving my innovative method of manufacture without departing from the spirit and scope of my invention and without sacrificing any of its advantages, it is to be understood that all matter herein is to be interpreted as illustrative and not in any limiting sense.
Having described a method of manufacture for a pressure vessel having especial utility it is now desired to set forth the following claims for the invention.
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A process of manufacture to produce low cost pressure vessels from a length of metal tubing by use of localized heat and/or axial tensile force to shrink the diameter of the tubing at selected locations of a predetermined starting length approximately one diameter long and many diameters apart to permit subsequent separation to form open-ended pressure vessels. Subsequent conventional swaging operations could thicken and reduce the end diameters so they can be threaded.
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CROSS REFERENCE TO RELATED APPLICATION
This application is a continuation-in-part of U.S. patent application Ser. No. 725,004, filed on Apr. 19, 1985, now U.S. Pat. No. 4,621,572.
TECHNICAL FIELD
This invention relates generally to an apparatus and method for processing beans or the like and more particularly to the cutting of the pods of fava beans to facilitate separation of the seeds of the beans from the pods.
Background Art
The commercial marketability of various types of podded beans largely depends on the ability of a processor to expeditiously and economically separate the seeds from the pods thereof. The inability to provide an apparatus and method for efficiently effecting such separation is particularly apparent in respect to fava beans which have a relatively tough pod. In conventional practice, the pods are manually removed by the use of knives or the like which is time consuming and gives rise to uneconomically high processing costs.
DISCLOSURE OF INVENTION
The apparatus and method of the present invention overcome the above, briefly described problems by expeditiously, efficiently and economically separating the seeds from the pods of fava beans or the like without damaging the seeds.
The apparatus comprises first means for moving the beans along a path, second means for cutting the pods during their movement along the path to facilitate separation of the seeds from the pods, and third means for squeezing the pods to force the seeds out of the pods.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects and advantages of this invention will become apparent from the following description and accompanying drawings wherein:
FIG. 1 is the frontal isometric view of an apparatus for processing fava beans;
FIG. 2 is an enlarged isometric view of a cutting and separation assembly mounted in the apparatus to cut the pods of the fava beans and to separate their seeds from the pods;
FIG. 3 is an exploded view of component parts of the apparatus;
FIG. 4 is a backside elevational view of the apparatus, showing a drive system therefor;
FIG. 5 is an end elevational view of the apparatus and drive system, taken in the direction of arrows V--V in FIG. 4; and
FIGS. 6 and 7 are views taken in the direction of arrows VI--VI and VII--VII in FIGS. 4 and 5, respectively.
BEST MODE OF CARRYING OUT THE INVENTION GENERAL DESCRIPTION
FIG. 1 illustrates an apparatus 10 for processing fava beans B or the like comprising a hopper 11, shown in phantom lines, for delivering the fava beans to an upstream end of a cutting and separation assembly 12. As more clearly shown in FIG. 2, assembly 12 comprises a pair of endless gear belts 13 arranged generally vertically to converge towards each other in a downward direction to transport the fava beans along a path P therebetween. A cutting assembly 14 has a razor blade 15 or other suitable cutter mounted in a spring-loaded and depth gauged fixed position on the apparatus to project into path P.
The blade functions to cut or slice a pod or husk H of each fava bean B prior to further descent of the fava bean downwardly through the assembly. The gear belts frictionally grip the bean therebetween during the cutting step of the process whereafter the beans are squeezed between the belts by a first set of squeeze or cam rollers 16 to squeeze-out and eject seeds S from pods H. A second set of squeeze or cam rollers 17 are mounted downstream of the first set of cam rollers and function to complete the squeezing of the husks to insure that all of the seeds are ejected therefrom.
As described above, the fava bean has a relatively tough pod that must be sliced before the seeds can be separated from the pod. Applicant's hereinafter described apparatus and method will effect such separation expeditiously, efficiently and economically without damaging the seeds. As further shown in FIG. 1, the seeds may be ejected into a chute 18 for storage in a container 19 whereas spent pods H are free to drop under the influence of gravity into a container (not shown) for disposal purposes.
DETAILED DESCRIPTION
Referring to FIGS. 1 and 3, apparatus 10 is mounted on a fixed base or bed plate 20 having a pair of downwardly converging fixed guides 21 secured thereon to receive fava beans B from hopper 11 and drop them between belts 13. Each belt 13 can be composed of a suitable plastic material or a standard fabric or cord (nylon or steel) impregnated and bonded by vulcanized rubber compounds to form a plurality of longitudinally and evenly spaced inner and outer teeth 22 thereon. As described more fully hereinafter, the outer teeth, when facing path P, function to firmly frictionally grip (but not damage) the pods of the fava beans during their descent through assembly 12 and, cooperating with cam rollers 16 and 17, will uniformly apply increasing compressive forces to either sides of the beans to eject seeds S without damaging them.
As shown in FIG. 2, blade 15 is epoxied or otherwise suitably secured between the lower ends of a pair of fixed spring steel wires 15a. The wires are suitably crimped to engage and follow any irregular centour of the pod of a bean, due to their inherent resilient flexing action, to maintain the appropriate cutting pressure on the bean. The cutting edge of the blade protrudes beyond the undersides of the wires at a distance slightly less than the thickness of the pod. This arrangement will function to automatically control and gauge the depth of the cut into the pod to insure that the seeds are not cut or otherwise damaged. A vinyl cover 15b or the like can be mounted on the wires for protection purposes, if so desired (FIGS. 1 and 3).
Each gear belt 13 is mounted on an upper idler sprocket 23 and a lower drive sprocket 24. A belt guide and backup member 25 is fixedly secured on bed plate 20 to press against the backside of each gear belt to define the desired converging relationship therebetween. Such converging relationship will effect the gripping function through cutting assembly 15 and ready the cut beans for further travel through the squeezing assembly, including cam rollers 16 and 17. As shown in FIGS. 2 and 3, members 25 are arranged to define a downwardly converging channel between belts 13 that is relatively wide at its top and gradually narrows at its bottom whereat seeds 5 are forced to initiate their transverse movement out of pod H as the bean approaches rollers 16 (FIG. 2).
A cover plate and belt guard 26 is secured on bedplate 20 by a plurality of machine bolts 27 and nuts 28 to at least substantially cover and protect the gear belts. A centrally disposed opening 29 is formed through the cover plate to accommodate cutter 15 and to provide visual inspection during the processing of the beans. As shown in FIG. 2, first set of cam rollers 16 are each rotatably mounted on a shaft 30, secured on bedplate 20, and have a frontal edge positioned at a distance "X" from the bedplate that is less than the width of belt 13. A frontal edge of each cam roller 17, rotatably mounted on a shaft 31, is disposed at a distance "Y" that is substantially aligned with the outer edge of belt 13 with the distance "Y" being greater than distance "X". In addition, rollers 16 are spaced apart from each other at a distance, transverse to path P, that is greater than the separation distance between rollers 17.
This "staggered" and separation relationship between the first and second sets of cam rollers will insure that the first set of cam rollers will initiate the squeezing function for ejecting seeds S (approximately 1/2 of the bean is squeezed). The second set of cam rollers will function to completely squeeze the bean, to insure ejection of all of the seeds. Belt guides 25 can be suitably positioned and configured, relative to path P and against belts 13, to further aid in initiating the squeezing function, as shown in FIG. 2.
FIGS. 4 and 5 are backside and end elevational views of vertically disposed bed plate 20 and further show a drive system for gear belts 13. In particular, a motor-driven drive sprocket 32 has a drive chain 33 entrained thereover to drive a pair of driven sprockets 34, each connected to a respective gear belt drive sprocket 24 (FIG. 3) by a shaft 35. The entrainment of the chain over sprockets 34 in the manner illustrated in FIG. 4 insures that gear belts 13 will be matched in speed and move in the desired opposite directions for bean processing purposes.
As shown in FIGS. 3-7, a generally triangular and vertically disposed plate 36 can be used to press against the backsides of beans B to aid members 25 in pushing seeds S out of pods H, after the pods have been cut and before descent of the beans through rollers 16, 17. Wedge-shaped plate 36 is mounted on bed plate 20, vertically between blade 15 and the rollers. FIGS. 6 and 7 illustrate an example of an adjustable mounting arrangement for plate 36 whereby the plate can be adjusted to define a variable acute angle "a" between a frontal edge 37 of the plate and path P.
Such adjustment may be used to vary angle "a" to accomodate beans of varied circumference. For example, one batch of beans may have relatively small circumferences requiring a larger angle "a" than is required for a batch of beans having larger circumferences. If this angle is too large for the larger circumferenced beans, the plate may tend to push the beans out from between the belts.
Plate 36 is pivotally mounted at its upper, narrow end on a bracket 38, secured on the backside of bed plate 20, by a pin 39. Plate 36 projects forwardly through a vertically disposed and elongated slot 40, formed through bed plate 20, to selectively permit changes in angle "a" and thus the inclination of frontal edge 37 in its downwardly diverging relationship relative to path P and the backsides of beans B.
The adjustment means for selectively adjusting angle "a" and the extent by which the lower, wide end of plate 36 projects through slot 40 comprises a set screw 41 threadably mounted on a second bracket 42, also secured on the backside of bed plate 20. A lock nut 43 can be used to releasably fix the axial position of the set screw on bracket 42 and thus angle "a".
A second nut 44 (or standard cup-shaped spring retainer) is epoxied or otherwise suitably secured on a distal end of set screw 41. A compression coil spring 45 is preferably mounted between nut 44 and a mounting pin or post 46, secured on a backside of plate 36, to constantly apply a predetermined biasing force on the plate and towards path P. The "spring-loading" of the plate in this manner will compensate for irregularities in the sizes and shapes of the beans.
Alternatively, plate 36 can be bolted directly to bed plate 36 in a fixed manner. A selected number of plates, having varied wedge-shapes and varied defined angles of inclination "a", could be kept on hand by the operator. The plate can be replaced as the need arises to accomodate different batches of beans having varied circumferences, i.e., a less pronounced wedge-shape and angle "a" for beans having relatively smaller circumferences.
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The pods of fava beans are cut and then squeezed to separate the seeds from the pods of the beans. The beans are fed vertically and downwardly between a pair of converging conveyor belts that frictionally engage and move the beans along a path. A stationary spring-loaded and depth gauged cutting blade is disposed in the path to cut the pods whereafter the belts function to squeeze the pods to force the beans therefrom.
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CROSS-REFERENCE TO RELATED APPLICATION
This application is a continuation-in-part of U.S. patent application Ser. No. 539,910, filed Oct. 7, 1983 now abandoned.
BACKGROUND OF THE INVENTION
This invention relates to methods of flocculating particulate solids suspended in aqueous media.
In the processing of mineral ores, coal and other industrial slurries, it is often necessary to flocculate suspended solids from aqueous media, and in particular, acidic aqueous media. For example, in the case of mineral ores and coal containing materials, it is often desirable to subject such ores and coal products to an acid treatment or an acid leaching or acid digestion step in order to facilitate the separation of the mineral or coal values from the unwanted clays, sand and other finely divided solids. Such acid treatment steps often generate suspensions of finely divided solids in acidic aqueous media from which solids must be flocculated before further processing can occur or the liquid media can be discharged, recycled or used. Conventionally, such flocculation is accomplished by contacting the suspension with a water-soluble copolymer of acrylamide and acrylic acid or acid hydrolyzed polyacrylonitrile as described in British Pat. No. 760,279 and U.S. Pat. No. 3,418,237. Unfortunately, these polymers, i.e., the nonionic polyacrylamide and the anionic copolymers of acrylamide and acrylic acid are not as effective in flocculating suspended solids from acidic aqueous media as is desired.
More recently, the use of anionic polymers has been disclosed as being effective in flocculating various systems as is described in U.S. Pat. Nos. 3,717,574 and 4,342,653. However, the methods of flocculation taught in said patents are not as effective in providing supernatant liquids of high clarity (i.e., free of fine particulate matter) as is desirable. That is, due to the nature of impurities such as fine amorphous silica particles and low pH colloids, the clarity of the supernatant liquids is poor.
The use of an amount of anionic polymer containing a carboxylic acid, a carboxylic acid anhydride and a carboxylic acid salt; and a cationic polymer to remove coal fines and clay from an aqueous suspension is disclosed in U.S. Pat. No. 3,408,293. Unfortunately, such a combination provides a method for clarifying systems exhibiting a limited pH range. In addition, such a combination requires careful control of amounts of polymers employed and of settling rates of flocculated particles.
In view of the deficiencies of the prior art, it would be highly desirable to provide an improved method for flocculating suspended solids from aqueous media which is effective in providing a supernatant liquid having improved clarity.
SUMMARY OF THE INVENTION
The present invention is such an improved method for flocculating suspended particulate solids from an acidic aqueous medium and for increasing the clarity of said aqueous medium. This method comprises initially contacting the aqueous medium (i.e., suspension) with a flocculating amount of a water-soluble polymer having an anionic character comprising a nonionic, ethylenically unsaturated monomer and an ethylenically unsaturated sulfonate monomer; followed by contacting the suspension with a clarifying amount of a water-soluble polymer having a cationic character comprising a nonionic, ethylenically unsaturated monomer and an ethylenically unsaturated monomer containing cationic moieties wherein said polymer having an anionic character contains a molar concentration of sulfonate moieties sufficient to provide flocculant activity in the acidic aqueous medium that is greater than the flocculant activity of an acrylamide/acrylic acid polymer having the same molecular weight and a molar concentration of carboxylate moieties similar to the molar concentration of sulfonate moieties of said polymer having an anionic character, and wherein said polymer having a cationic character provides clarifying activity of the supernatant liquid which is greater than that clarity provided to said aqueous medium by said polymer having an anionic character.
Surprisingly, the practice of the present invention enables one to achieve about the same or better rate or degree of flocculation than can be achieved using conventional anionic copolymers. In addition, the present invention enables one to achieve a better degree of clarity of supernatant liquid than has been achieved using conventional flocculating techniques.
The practice of the present invention is found to successfully flocculate any of a wide variety of suspended solids from aqueous media such as in mining operations, waste treatment, etc. Of particular interest for treatment in accordance with this invention are the acidic suspensions of minerals and acidic ore pulp such as pulps made from weathered ores and mineral products, acid leached gold ores, copper ores, copper flotation concentrates, copper tailings and acid leached copper residues, acid leached bauxite ores, acid leached beryllium or palladium ores, water or acid zinc sulfide concentrates, acid leached cyanidation tailings containing pyrite, gold and uranium bearing materials, acidic titanic sulfate digestion residues from crude titaniferous materials such as ilmenite or concentrates, etc., as well as acidic suspensions of ores and minerals such as zinc refinery sludges, flotation products, zirconium oxide and iron oxide slimes, and various coal slurries, particularly coal slurries containing bituminous and anthracite coal fines.
DETAILED DESCRIPTION OF THE INVENTION
For purposes of this invention, the term "acidic suspension" is meant to include any aqueous suspension of solid particles wherein "acidic" or "highly acidic" mean that this aqueous media has a pH less than about 4, preferably less than about 3, more preferably from about 0.2 to 2, most preferably from about 0.5 to 1.2. The particulate solids which may be suspended in such suspensions include any of the materials that are characteristic in the foregoing exemplified suspensions. In addition to such acidic suspensions as exemplified hereinbefore, other suspensions that are suitably employed include various acidic aqueous suspensions of cellulosic materials that are characteristically found in the manufacture of paper, as well as suspensions occurring in the manufacture of concrete and sugar wherein valuable or unwanted gangue is separated from liquid phase via filtration, sedimentation or centrifugation. Of these acidic suspensions, those derived from various metal ore refining processes, particularly those used in the recovery of uranium, copper, gold, beryllium and vanadium, are preferred with the suspensions characteristic of the recovery of uranium being most preferred. In general, the acidic suspensions contain from about 1 to about 45, preferably from about 6 to about 38, most preferably from about 10 to about 28, weight percent of suspended solids.
By the term "ethylenically unsaturated monomer containing anionic moieties" is meant a monomer containing, for example, sulfonate and optionally carboxylate moieties. Thus, the preferred anionic polymers of this invention are the sulfonate polymers. Sulfonate polymers suitably employed in the practice of this invention are polymers comprising nonionic, ethylenically unsaturated monomers with anionic, ethylenically unsaturated monomers containing sulfonate or sulfonic acid moieties. The sulfonate polymer contains sufficient water-soluble monomer to render the polymer water-soluble and sufficient sulfonate (SO 3 M wherein M is H, metal or ammonium) to increase the flocculant efficiency of the polymer to a value above that of a similar polymer of the nonionic monomer and a carboxylate comonomer. Preferred polymers contain from about 5 to about 95, most preferably from about 50 to about 80, weight percent of the nonionic monomer and from about 95 to about 5, most preferably from about 50 to about 20, weight percent of the sulfonate monomer. Polymers also can contain, rather than a portion of said nonionic monomer, up to about 30 weight percent of an ethylenically unsaturated carboxylic acid (e.g., acrylic or methacrylic acid) or a metal or ammonium salt thereof, more preferably from about 5 to about 30, most preferably from about 5 to about 15, weight percent of such carboxylic acid or salt. The molecular weight of the sulfonate polymer is sufficient to enable the polymer to function as a flocculant, but less than that which would render the polymer insoluble in water. Preferred sulfonate polymers have number average molecular weights (Mw) in the range from about 100,000 to about 10 million, most preferably from about 2 million to about 8 million. For purposes of this invention, a water-soluble polymer is one which forms a thermodynamically stable mixture when combined with water. These mixtures form spontaneously and include (1) true solutions in which the individual polymer molecules are dispersed and (2) micellular or colloidal solutions wherein the polymer molecules are aggregated to some extent but wherein such aggregates are no larger than colloidal size. It is also desirable that such polymers are soluble in brines or other such aqueous solutions.
Exemplary nonionic monomers suitably employed in the practice of this invention are those ethylenically unsaturated monomers that are sufficiently water-soluble to form at least a 10 weight percent solution when dissolved in water and readily undergo addition polymerization to form polymers that are water-soluble. Examples of such nonionic monomers include ethylenically unsaturated amides such as acrylamide, methacrylamide and fumaramide; their water-soluble N-substituted nonionic derivatives such as the N-methylol derivatives of acrylamide and methacrylamide as well as the N-methyl and N,N-dimethyl derivatives of acrylamide and methacrylamide; hydroxyalkyl esters of unsaturated carboxylic acids such as hydroxyethyl acrylate and hydroxypropyl acrylate; and the like. Of the foregoing nonionic monomers, the ethylenically unsaturated amides are preferred with acrylamide being especially preferred.
Examples of suitable ethylenically unsaturated sulfonate monomers include N-sulfoalkyl, α,β-ethylenically unsaturated amides such as 2-acrylamido-2-methylpropane sulfonic acid, 2-aacrylamido propane sulfonic acid, 2-acrylamido ethane sulfonic acid and the alkali metal salts thereof such as the sodium and potassium salts thereof as well as other such monomers listed in U.S. Pat. No. 3,962,673 which is hereby incorporated by reference; sulfoalkyl esters of unsaturated carboxylic acids such as 2-sulfoethyl methacrylate and other such sulfoalkyl esters as listed in U.S. Pat. No. 4,075,134 which is also incorporated by reference as well as the alkali metal salts thereof; sulfoarylalkenes such as vinylbenzyl sulfonic acid and the various salts of vinylbenzyl sulfonate, p-styrene sulfonic acid and the salts thereof; sulfoalkenes such as vinyl sulfonic acid and salts thereof; and the like. Of the foregoing sulfonate monomers, the sulfoalkyl derivatives of acrylamide and methacrylamide are preferred with those of acrylamide being especially preferred, particularly 2-acrylamido-2-methylpropane sulfonic acid (AMPS), 2-acrylamido-2-propane sulfonic acid and the salts thereof. In the most preferred embodiments, the sulfo group is in the form of an alkali metal sulfonate salt such as sodium sulfonate.
The most preferred sulfonate polymers for the purpose of this invention are polymers comprising from about 50 to about 80 weight percent of acrylamide with from about 20 to about 50 weight percent of an AMPS monomer preferably in salt form. Such polymers often contain, rather than a portion of said acrylamide monomer, from about 0 to about 30, preferably from about 5 to about 15, weight percent of acrylic acid or salt thereof such as sodium acrylate. It is understood that the acrylate moieties can be provided by, for example, polymerizing an unsaturated acid such as acrylic acid, or by hydrolyzing a species such as polymerized acrylamide.
The aforementioned sulfonate polymers are readily prepared by conventional procedures such as aqueous phase polymerization as described by Schildknecht (II) in Polymer Process, Interscience, 191-194 (1956) or disperse aqueous phase polymerization as described in U.S. Pat. No. 3,284,393. Normally such polymerization is carried out in the presence of a polymerization initiator capable of generating free radicals. Preferably, this free radical initiator is employed in amounts from about 0.0001 to about 0.1 weight percent of initiator based on the monomers. Exemplary polymerization initiators include the inorganic persulfates such as potassium persulfate, ammonium persulfate and sodium persulfate, azo catalyst such as azobisisobutyronitrile and dimethyl azoisobutyrate; organic peroxygen compounds such as benzyl peroxide, t-butyl peroxide, diisopropylbenzene hydroperoxide and t-butyl hydroperoxide. Of these initiators, the organic peroxygen compounds are preferred. Particularly preferred are combinations of these peroxygen compounds with reducing agents to provide conventional redox catalyst systems. Examples of such reducing agents are sodium bisulfite, sulfur dioxide, sodium borohydride and the like. In addition to the aforementioned ingredients, the polymerization recipe optionally includes chain transfer agents such as isopropyl alcohol, chelating agents, buffers, salts and the like.
By the term "ethylenically unsaturated monomer containing cationic moieties" is meant such a monomer containing, for example, a quaternized nitrogen moiety. Cationic polymers suitably employed in the practice of this invention are copolymers of the aforementioned nonionic, monomers such as acrylamide and methacrylamide with a quaternized nitrogen-containing, ethylenically unsaturated monomer such as acryloylalkyl trialkyl ammonium salts, e.g., acryloylethyl trimethyl ammonium chloride; methacryloylalkyl trialkyl ammonium salts, e.g., methacryloylethyl trimethyl ammonium chloride; acrylamido- and methacrylamidoalkyl trialkyl ammonium salts, e.g., acrylamidopropyl trimethyl ammonium chloride and methacrylamidopropyl trimethyl ammonium chloride. Such copolymers have generally low molecular weight with preferred copolymers having weight average molecular weights (Mw) in excess of about 10,000. High molecular weight copolymers can also be employed. Such copolymers have molecular weights in excess of 100,000, and most preferred high molecular weight copolymers have molecular weights (Mw) in the range of from about 1 million to about 25 million. These cationic copolymers have sufficient cationic moiety to increase the capability of the copolymer to flocculate and clarify aqueous suspensions of particular matter. Such cationic copolymers contain from about 1 to about 90 weight percent of cationic monomers. Preferred cationic copolymers have from about 1 to about 30 weight percent, more preferably from about 2 to about 20 weight percent cationic moiety. Also suitable are the quaternized polyalkylene polyamines.
The aforementioned cationic polymers are readily prepared by conventional procedures such as disperse aqueous phase polymerization as described in U.S. Pat. No. 3,284,393. Low molecular weight cationic copolymers are advantageously prepared by Mannich base modification as is taught in U.S. Pat. No. 4,14,827 which is incorporated herein by reference.
In the practice of this invention, the suspensions can be clarified to a level such that the transmittance of light through the aqueous liquid is higher than that achieved using previous techniques, and is often in excess of 75 percent and under preferred conditions is in excess of 85 percent. Such improved flocculating ability and clarity is possible in a wide pH range, as for examle, from about 0.2 to about 14. It is understood that an inorganic coflocculant can also be employed in the practice of this invention.
In practice, the suspension is contacted with an amount of the aforementioned sulfonate (i.e., anionic) polymer which is sufficient to remove the suspended particles from the aqueous phase. In preferred embodiments wherein the acidic suspension is an acidic ore pulp or suspension of mineral material which contains, in addition to the mineral value, a clay or similar silicate material, the sulfonate polymer is added in an amount sufficient to flocculate the clay particles as well as suspended metal values. In cases of where the metal values are later actually dissolved in the aqueous phase, the clay particles are flocculated and the dissolved metal values are recovered via conventional techniques such as electrolysis, precipitation, or the like. Preferably, the amount of sulfonate polymer employed to flocculate the suspended solids is in the range from about 1 to about 5000 weight parts of the sulfonate polymer per million weight parts of solids in the suspension, more preferably from about 5 to about 1000 ppm, most preferably from about 10 to about 500 ppm. Most preferably, the amount of sulfonate polymer which is employed is greater than or about equal to the amount of cationic polymer which is employed. The mode of adding the sulfonate polymer to the suspension is not particularly critical as long as a uniform dispersion of the polymer in the acidic suspension is achieved. Advantageously, however, the polymer is dissolved in an aqueous solution in concentrations, from about 0.001 to about 2 weight percent, most preferably from about 0.025 to about 0.2 weight percent prior to the addition to the suspension. It is understood that the sulfonate polymer can be added as a water-in-oil emulsion to the suspension. Examples of such emulsions are described in U.S. Pat. RE No. 28,474. Such emulsions contain sufficient water-soluble surfactant to cause inversion of the emulsions when combined with such a suspension. Alternatively, the emulsion may be inverted to form an aqueous solution and then added to the suspension.
Following the addition of the anionic copolymer to the suspension, said suspension is contacted with an amount of the aforementioned cationic coplymer which is sufficient to remove the remaining suspended particles from the aqeous phase.
In preferred embodiments wherein the suspension contains suspended clay particles, the cationic polymer is added in amounts sufficient to remove both suspended particles and clay particles from the aqueous phase. Preferably, such amounts are in the range from about 0.1 to about 500 weight parts of the polymer per million weight parts of the suspension, more preferably from about 0.5 to about 25 ppm, most preferably from 1 to about 10 ppm. The mode of adding the cationic polymer to the suspension is not particularly critical as long as a uniform dispersion of the polymer in the aqueous suspension is achieved. Advantageously, however, the cationic polymer is dissolved in an aqueous solution in concentrations from about 0.2 to about 1.5 weight percent, most preferably from about 0.3 to about 0.6 weight percent prior to addition to the suspension. It is understood that the cationic polymer can be added to the coal liquor as a water-in-oil emulsion, e.g., as described in U.S. Pat. RE No. 28,474, which contains sufficient water-soluble surfactant to cause inversion when combined with the aqueous medium. Alternatively, the emulsion may be inverted to form an aqueous solution and then added to the coal liquor. The time at which the cationic polymer is added to the suspension can vary from several seconds after the anionic polymer has been dispersed in the suspension, until the time at which flocculation is substantially complete.
The following examples are intended to illustrate the invention and are not intended to limit the scope thereof. In the examples, all parts and percentages are by weight unless otherwise specified.
GENERAL PROCEDURE FOR CLARIFICATION OF ACIDIC SUSPENSION
The sulfonate copolymer is first dissolved in water to provide a 0.1 percent solution of the anionic polymer. This solution is allowed to stand for a period of 0.5-2 hours. It is diluted to a concentration of 0.025 percent immediately prior to use.
The acidic suspension containing primarily clay particles as the suspended particulate is then combined with a given amount of the anionic polymer solution. After 2 minutes of mixing, the cationic polymer is added to the acidic suspension. The resulting suspension (250 ml) is placed into a 250 ml graduated cyclinder which is stoppered and rotated end over end for 6 consecutive rotations. The flocculation of suspended solids is observed by measuring the rate of drop of interface between suspended solids and clear supernatant (Settling Rate). The suspension comprises kaolinite, montmorillonite (sodium bentonites), calcium bentonite, amorphous silica, amorphous aluminum hydroxide and calcium sulfate crystals such that the pH of the suspension is 1.5.
EXAMPLE 1
PREPARATION OF SULFONATE POLYMER
Into a liter reaction kettle equipped with a stirrer, thermocouple, nitrogen inlet tube, gas vent and a heating mantle are charged the following with stirring:
(1) 54 g of a 50 percent solution of sodium 2-acrylamido-2-methylpropane sulfonate (NaAMPS) in water (pH=9-9.5)
(2) 126 g of a 50 percent solution of acrylamide (AAM) in water (pH=5.5)
(3) 420 g of water
(4) 5 g of sodium carbonate.
Nitrogen is bubbled through the stirred solution for 1 hour. To this stirred solution are then added the following solutions:
(1) aqueous solution of pentasodium salt of (carboxymethylimino)bis(ethylenenitrilo)-tetraacetic acid (V-80) sufficient to provide 4000 ppm of V-80 in the stirred solution
(2) aqueous solution of t-butyl hydroperoxide (TBHP) sufficient to provide 400 ppm of TBHP in the stirred solution
(3) aqueous solution of sodium borohydride (NaBH 4 ) sufficient to provide 3 ppm of NaBH 4 in the stirred solution.
The temperature of the stirred solution rises to 15°-25° C. and is maintained at such temperature for 1 hour. The resulting aqueous solution of AAM/AMPS copolymer is removed and dried to a white solid. The copolymer contains 30 percent NaAMPS and 70 percent AAM and has an Ostwald viscosity (0.5 percent copolymer in 4 percent NaCl in water at 25° C.) of 35.8 centipoises.
The cationic polymer which is employed for purposes of illustration is a dimethylaminomethyl polyacrylamide and is sold commercially as Separan* CP-HF flocculant.
Following the aforementioned general procedure, the above-described copolymer is used to clarify three acidic suspensions and the results are set forth in Table I.
TABLE I__________________________________________________________________________ RatioPolymer Type.sup.1 Anionic PolymerSample No. Anionic Cationic Cationic Polymer.sup.2 Settling Rate.sup.3 Clarity.sup.4__________________________________________________________________________1 AAM/AMPS AAM/DMAM 3:1 3.8 10C-1* AAM/AMPS -- -- 0.7 2C-2* AAM/DMAM AAM/AMPS 1:3 2.2 2__________________________________________________________________________ *Not an example of the invention. .sup.1 Anionic polymer is 70/30 ratio of AAM/AMPS (acrylamide/sodium salt). Cationic polymer is 15/85 ratio of AAM/DMAM (acrylamide/dimethylaminomethyl acrylamide). .sup.2 Ratio is 15 ppm:5 ppm. .sup.3 Settling rate is in inch/minutes. .sup.4 Clarity is measured by pouring the supernatant liquid into a wedge shaped container and observing the numbers which are calibrated on the opposite side of the wedge. The higher the number, the greater the clarity.
The data in Table I indicates that the method of this invention provides an increased settling rate and increased clarity to the aqueous medium.
EXAMPLE 2
A sulfonate copolymer comprising in polymerized form about 70 weight percent acrylamide and about 30 weight percent 2-acrylamido-2-methylpropane sulfonic acid and is similar to that sulfonate copolymer described. Example 1 is provided and is designated as Polymer A. A cationic polymer which is sold commercially as Separan® CP-7HS and is similar to that cationic polymer described in Example 1 is provided and is designated as Polymer B. An anionic polymer comprising, in polymerized form, about 70 weight percent acrylamide and about 30 weight percent sodium acrylate, and which is sold commercially as Separan® AP-273 is provided and is designated as Polymer C.
A suspension comprising about 95 weight percent deionized water and about 5 weight percent kaolin clay is provided and the pH of the suspension was adjusted to the desired pH using concentrated sulfuric acid. A suspension comprising about 95 weight percent deionized water and about 5 weight percent montmorillonite is provided and the pH of the suspension is adjusted to the desired pH using concentrated sulfuric acid. A suspension comprising about 90 weight percent deionized water and about 10 weight percent calcium bentonite is provided and the pH of the suspension is adjusted to the desired pH using concentrated sulfuric acid.
The suspensions were each treated with Polymer A only; Polymer A and Polymer B; and Polymer C and Polymer B in a manner as described in Example 1. The settling rates and clarity as defined in footnotes 3 and 4 of Example 1 are determined.
Results are presented in Table II.
TABLE II__________________________________________________________________________ Treatment (Amount) (Amount) pH of SettlingSample Suspension Polymer 1 (ppm) Polymer 2 (ppm) Suspension Rate Clarity__________________________________________________________________________C-1 Kaolin Clay A (48) -- -- 1 0.2 31 Kaolin Clay A (48) B (16) 1 1.5 10C-2 Kaolin Clay C (48) B (16) 1 0.5 6C-3 Kaolin Clay A (48) -- -- 2 0.8 72 Kaolin Clay A (48) B (16) 2 2.5 10C-4 Kaolin Clay C (48) B (16) 2 1.0 7C-5 Kaolin Clay A (48) -- -- 3 0.5 63 Kaolin Clay A (48) B (16) 3 1.0 10C-6 Kaolin Clay C (48) B (16) 3 0.4 5C-7 Montmorillonite A (96) -- -- 1 0.1 14 Montmorillonite A (96) B (32) 1 0.5 4C-8 Montmorillonite C (96) B (32) 1 0.1 1C-9 Montmorillonite A (112) -- -- 2 03 25 Montmorillonite A (112) B (37) 2 1.0 6 C-10 Montmorillonite C (112) B (37) 2 0.4 3 C-11 Montmorillonite A (112) -- -- 3 0.3 36 Montmorillonite A (112) B (37) 3 1.0 6 C-12 Montmorillonite C (112) B (37) 3 0.5 3 C-13 Ca Bentonite A (24) -- -- 1 1.0 27 Ca Bentonite A (24) B (8) 1 2.2 10 C-14 Ca Bentonite C (24) B (8) 1 1.0 2 C-15 Ca Bentonite A (24) -- -- 2 0.8 18 Ca Bentonite A (24) B (8) 2 2.3 9 C-16 Ca Bentonite C (24) B (8) 2 1.2 2 C-17 Ca Bentonite A (24) -- -- 3 1.0 ˜09 Ca Bentonite A (24) B (8) 3 2.2 6 C-18 Ca Bentonite C (24) B (8) 3 0.9 ˜0__________________________________________________________________________
The data in Table II indicate that the treatment using the process of this invention provides good settling rates and clarity.
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An improved method for flocculating suspended particulate solids from an acidic aqueous medium and for clarifying said aqueous medium comprises initially contacting the suspension with a water-soluble polymer having an anionic character followed by contacting the suspension with a water-soluble polymer having a cationic character. Such method is particularly useful in clarifying acidic aqueous media used in mining operations, etc.
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CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a National Phase application under 35 U.S.C. § 371 of International Application No. PCT/GB01/01910 filed May 2, 2001 and claims the benefit of Great Britain Application No. 0011356.3 filed May 12, 2000.
The present invention relates to materials for use in medicine, in particular medical implant materials. The invention further provides a method of improving the biocompatibility of a medical implant material.
BACKGROUND
The use of artificial biomaterials is becoming increasingly widespread in several areas of medical treatment. For example, biomaterials are now used in the repair of damaged tissue (e.g. bone and skin), in prosthetic devices such as artificial hip and knee joints, heart valves, and blood vessels, and in drug delivery devices. However, one of the challenges that remains in this field of medicine is the provision of biomaterials with improved biocompatibility properties, which can be readily colonized by host cells.
The study of implant surface and biomaterial tissue interface reactions is essential for the continued improvement of implant performance. A review by Blitterwijk et al., (1991) discusses the importance of the reactions of cells at implant surfaces in determining the biocompatibility of the implant (i.e. how well the implant is accepted by the surrounding tissues and by the body as a whole). Current research is aimed at making ‘bioactive materials’ that will readily permit integration of the material into the host tissue.
There is considerable interest in poly(ε-caprolactone) (PCL) as a potential bioactive material. It has been widely used for the last thirty years for the production of resorbable sutures, biomedical implants, drug delivery systems and vaccine formulation. Currently, PCL is being exploited for bone graft substitution (Coombes and Meikle, 1994), because it could overcome the problems of limited supply of bone, risk of infection such as HIV, additional surgical operations and long bony union times associated with either autografts or allografts.
PCL is a semi-crystalline linear resorbable synthetic aliphatic polyester, —(—O—(CH 2 ) 5 —CO—)—. When implanted in vivo, the polymer is readily degraded non-specifically by hydrolytic enzymes, esterases and carboxypeptidases. Pitt et al. (1981), showed that degradation of PCL in vivo and in vitro proceeds via hydrolytic chain scission of ester linkages until the segments are sufficiently small to diffuse through the polymer bulk. Once the polymer reaches the molecular weight of 5000 Daltons, significant weight loss is observed, which is dependent on particle size. Chain scission has also been shown to be associated with an increase in crystallinity, which partially determines the rate of degradation (see review by Smith et al., 1990).
The products generated from the degradation of PCL are either incorporated into the tricarboxylic acid (TCA) cycle and removed by the lungs in the form of carbon dioxide and water, or eliminated by direct renal secretion. Taylor et al. (1994) tested PCL in vitro for the acute toxicity of degradation products. They found that the pH of PCL in sterile distilled water and Tris buffer remained relatively constant over sixteen weeks, and that the samples degraded slightly more in Tris compared to in water. It has also been found that hydroxy radicals produced by inflammatory cells play a major role in the degradation of PCL in vitro (Ali et al., 1992, 1993) and in vivo (Ali et al., 1994). The bioresorbability and biocompatibility of PCL is reviewed by Vert et al., (1992).
Another favourable factor of PCL is that it can be blended with numerous other polymers, e.g. Poly(L-Lactide) (PLA), to produce co-polymers with optimised properties. PLA is one of the strongest polyesters and has a resorption time of greater than one year, probably in the range of 2-3 years. This would be advantageous, for example, in a 3-D tissue construct/scaffold, where the implant resorption rate needs to be adjusted according to the tissue repair rate.
Feng et al., (1983) synthesised a biodegradable block copolymer of poly(ε-caprolactone) with poly(DL-lactide). The copolymers possessed release properties similar to silicone rubber (one of the first non-degradable drug delivery systems) but their degradation rates were always faster than that of PCL or PLA homopolymers. They intended to combine the excellent permeability of PCL with the faster biodegradation rate of PLA. Pitt et al., (1979) did investigate PCL, PLA and their copolymers and demonstrated how variabilities in the permeability of the drug delivery system could be achieved using copolymers of PCL and PLA, because PCL is more permeable than PLA.
Jianzhong et al, 1995 used PCL and poly(ethylene glycol) (PEG) block copolymers as a drug release device. It was found that the increasing PEG content of the copolymer caused an increase in the hydrophilicity and a decrease in the crystallinity of the copolymer. Thus, the drug releas behaviour and the degradability of the copolymer can be controlled by adjusting the composition of the copolymer.
Chan and Pitt (1990) tested the degradability of PCL when fabricated by compression moulding, co-precipitation and solvent evaporation and found that the method of fabrication and the resulting morphology of the polymers plays a critical role in determining their relative rates of hydrolytic degradation. Compression moulding of PCL/polyglycolic acid-co-lactic acid blends, increased the rate of chain scission as compared to the other fabrication methods.
A problem with PCL is that it is a plastic at body temperature. Its mechanical properties make it ideal for drug delivery systems, but not for the internal fixation of bone. Lowry et al., (1997) made reinforced PCL with phosphate glass fibres in the form of intra-medullary pins for the internal fixation of bone. This study was performed in the rabbit model and histological evidence showed that the composite was well tolerated, with minimal inflammation around the pin. The review by Daniels et al. (1990) illustrates that the mechanical properties of polymers and composites can be improved by reinforcing the materials with alumina, alumina-boria-silica, calcium metaphosphate glass fibers and carbon.
As well as blending PCL with other synthetic polymers to control the degradation rate, improve the mechanical properties of the system and alter its permeability, PCL can also be blended with natural polymers, e.g. collagen, fibronectin, hyaluronic acid and glycosaminoglycans. These natural polymers are all part of the extracellular matrix (ECM) that cells produce and secrete. It is thought that by incorporating natural polymers with synthetic polymers, osteoconductance and biocompatibility properties could be combined with the physical and mechanical properties of the synthetic component, making bioartificial polymers a good bioactive biomaterial substitute.
Giusti et al., (1994) discuss the importance of blending collagen with polymeric materials for use as medical devices and show how blending also increases the mechanical and thermal properties as compared to the individual components. Cascone et al., (1994) demonstrated the use of collagen and hyaluronic acid based polymeric bioartificial polymers as a successful drug delivery system for the release of growth hormone.
Several reports have shown the importance of the ECM in cellular function Ruoslahti et al., 1985 and Ellis and Yannis, 1996). Cells initially attach to the biomaterial by physicochemical factors, e.g. charge, surface free energy or the water content of the biomaterial (Schamberger and Gardella, 1994), and then strongly adhere to ECM proteins, which have been deposited on the biomaterial surface. How the ECM is deposited, stabilised and configured on a particular biomaterial surface is still not known, however tissue transglutaminase (tTG) has been implicated in the stabilisation process. It is important to understand this process in order to control cellular responses to surfaces.
Transglutaminases (Enzyme Commission System of Classification 2.3.2.13) are a group of multifunctional enzymes that cross-link and stabilise proteins in tissues and body fluids (Aeschlimann and Paulsson, 1994 and Greenberg et al., 1991). In mammals, they are calcium dependent and catalyse the post-translational modification of proteins by forming inter and intra-molecular ε(γ-glutamyl) lysine cross-links. The bonds that form are stable, covalent and resistant to proteolysis, thereby increasing the resistance of tissues to chemical, enzymatic and physical disruption. In contrast to transglutaminases of mammalian origin, microbial transglutaminases are generally not Ca 2+ -dependent.
The number of proteins acting as glutaminyl substrates for transglutaminases is highly restricted since both the primary structure and conformation are critical. In contrast, the only requirement of the acyl-acceptor substrate is the presence of a suitable pi amine, e.g. the ε-amino group of peptide bound lysine residues and small primary amines. Different types of transglutaminase enzyme differ in their specificity for a given glutaminyl substrate. For example, the plasma transglutaminase blood coagulation factor XIIIa acts on a limited range of glutaminyl substrates compared to tissue (or type II) transglutaminase (tTG). Unlike Factor XIIIa, tTG also binds GTP and GDP, which is thought to be important in its regulation by Ca 2+ (see Smethurst and Griffin, 1996). A further key difference between the types of transglutaminase is in their distribution.
Although tTG has been mainly described as a cytosolic enzyme and does not contain a typical hydrophobic leader sequence for secretion, it may be found both in the cytosol and membrane associated depending on the cell type. The biological function of tTG has yet to be determined. However, there is now increasing evidence to suggest that tTG can act at the cell surface, facilitating cell adhesion (Borge et al., 1996) and cell spreading (Jones et al., 1997) and the modification of the extracellular matrix (ECM) (Aeschlimann et al., 1995, Barsigian et al., 1991, Bowness et al., 1988 and Bendixen et al., 1993).
The ability of transglutaminase enzymes to cross-link proteins has been exploited in the development of biological glues for promoting adhesion between tissue surfaces. For example, biological adhesive compositions comprising a tissue transglutaminase are disclosed in WO 94/28949. These compositions also comprise a divalent metal ion co-factor, which plays a regulatory role in the functional activity of transglutaminase enzymes (see Casadio et al., 1999 , Eur. J. Biochem. 262, 672-679).
SUMMARY OF THE INVENTION
A first aspect of the invention provides a medical implant material comprising a mammalian transglutaminase and a polymer, wherein the transglutaminase is provided in the absence of free divalent metal ions and wherein the polymer is associated with a binding protein for binding the transglutaminase.
By ‘medical implant material’ we include a material for implantation into the human or animal body, such as a material for use as an artificial tissue (e.g. bone, teeth and skin), prosthetic devices (e.g. joints, heart valves, blood vessels) and drug delivery devices.
By ‘mammalian transglutaminase’ we mean a member of the group of enzymes identified by Enzyme Commission System of Classification No. 2.3.2.13 (EC 2.3.2.13), wherein the enzyme is derived, directly or indirectly, from a mammalian source. Thus, we include transglutaminase prepared (i.e. extracted) from mammalian tissue samples, as well as mammalian transglutaminases expressed by recombinant means. We also include variants of naturally-occurring mammalian transglutaminases.
By ‘free divalent metal ions’ we mean unchelated divalent metal ions, such as Ca 2+ ions, which are available to interact with the transglutaminase and regulate the functional activity of the enzyme.
By ‘provided in the absence of’ free divalent metal ions we include transglutaminases which are provided in the presence of divalent metal ions that are bound to a chelating agent, and hence are not available to interact with the enzyme.
In a preferred embodiment of the first aspect of the invention the transglutaminase is a tissue transglutaminase.
In an alternative embodiment the transglutaminase is a plasma transglutaminase.
Preferably, the transglutaminase is prepared from mammalian tissue or cells.
More preferably, the transglutaminase is prepared from human tissue or cells. For example, the transglutaminase may be extracted from human tissue sources such as lung, liver, spleen, kidney, heart muscle, skeletal muscle, eye lens, endothelial cells, erythrocytes, smooth muscle cells, bone and macrophages. Advantageously, the transglutaminase is a tissue transglutaminase derived from human red cells (erythrocytes), or a plasma transglutaminase derived from either human placenta or human plasma.
Alternatively, the transglutaminase may be obtained from a culture of human cells that express a mammalian transglutaminase, using cell culture methodology well known in the art. Preferred cell line sources of such transglutaminases include human endothelial cell line ECV304 (for tissue transglutaminase) and human osteosarcoma cell line MG63.
It will be appreciated by those skilled in the art that tie source of the transglutaminase may be selected according to the particular use (e.g. site of implantation) of the medical implant material. For example, if the medical implant material is to be used as artificial bone, it may be beneficial for the material to comprise a bone-derived transglutaminase.
In an alternative embodiment of the first aspect of the invention, the transglutaminase is a recombinant transglutaminase. For example, recombinant factor XIII production is described in European Patent Application No. EP 268 772 A.
Nucleic acid molecules encoding a transglutaminase are known in the art. For example, the coding sequence for human coagulation factor XIII A1 polypeptide is disclosed in Grundmann et al, 1986, Proc. Natl. Acad. Si. USA 83(21), 8024-8028 (accession no. NM 000129). The coding sequence for human tissue transglutaminase is disclosed in Gentile et al., 1991, J. Biol. Chem. 266(1) 478-483 (accession no. M 55153).
Nucleic acid molecules encoding a transglutaminase may be used in accordance with known techniques, appropriately modified in view of the teachings contained herein, to construct an expression vector, which is then used to transform an appropriate host cell for the expression and production of the polypeptide of the invention. Methods of expressing proteins in recombinant cells lines are widely known in the art (see Sambrook et al. (1989) Molecular Cloning, A Laboratory Manual , Second Edition, Cold Spring Harbor, N.Y.). Exemplary techniques also include those disclosed in U.S. Pat. Nos. 4,440,859 issued Apr. 3, 1984 to Rutter et al, 4,530,901 issued Jul. 23, 1985 to Weissman, 4,582,800 issued Apr. 15, 1986 to Crowl, 4,677,063 issued Jun. 30, 1987 to Mark et al, 4,678,751 issued Jul. 7, 1987 to Goeddel, 4,704,362 issued Nov. 4, 1987 to Itakura et al, 4,710,463 issued Dec. 1, 1987 to Murray, 4,757,006 issued Jul. 12, 1988 to Toole, Jr. et al, 4,766,075 issued Aug. 23, 1988 to Goeddel et al and 4,810,648 issued Mar. 7, 1989 to Stalker, all of which are incorporated herein by reference.
The nucleic acid molecule, e.g. cDNA, encoding the transglutaminase may be joined to a wide variety of other DNA sequences for introduction into an appropriate host. The companion DNA will depend upon the nature of the host, the manner of the introduction of the DNA into the host, and whether episomal maintenance or integration is desired.
Generally, the DNA is inserted into an expression vector, such as a plasmid, in proper orientation and correct reading fame for expression If necessary, the DNA may be linked to the appropriate transcriptional and rational regulatory control nucleotide sequences recognised by the desired host, although such controls are generally available in the expression vector.
Thus, the DNA insert may be operatively linked to an appropriate promoter. Bacterial promoters include tile E. coli lacI and lacZ promoters, the T3 and T7 promoters, die gpt promoter, the phage λ PR and PL promoters, the phoA promoter and the trp promoter. Eukaryotic promoters include the CMV immediate early promoter, the HSV thymidine kinase promoter, the early and late SV40 promoters and the promoters of retroviral LTRs. Other suitable promoters will be known to the skilled artisan. Alternatively, the Baculovirus expression system in insect cells may be used (see Richardson et al., 1995), Methods in Molecular Biology V Q l 39, J Walker ed., Humana Press, Totowa, N.J.). The expression constructs will desirably also contain sites for transcription initiation and termination, and in the transcribed region, a ribosome binding site for translation. (Hastings et al, International Patent No. WO 98/16643, published Apr. 23, 1998).
The vector is then introduced into the host through standard techniques. Generally, not all of the hosts will be transformed by the vector and it will therefore be necessary to select for transformed host cells. One selection technique involves incorporating into the expression vector a DNA sequence marker, with any necessary control elements, that codes for a selectable trait in the transformed cell. These markers include dihydrofolate reductase, G418 or neomycin resistance for eukaryotic cell culture, and tetracyclin, kanamycin or ampicillin resistance genes for culturing in E. coli and other bacteria. Alternatively, the gene for such selectable trait can be on another vector, which is used to co-transform the desired host cell.
Host cells that have been transformed by the recombinant DNA of the invention are then cultured for a sufficient time and under appropriate conditions known to those skilled in the art in view of the teachings disclosed herein to permit the expression of the transglutaminase, which can then be recovered.
The recombinant transglutaminase can be recovered and purified from recombinant cell cultures by well-known methods including ammonium sulphate or ethanol precipitation, acid extraction, anion or cation exchange chromatography, phosphocellulose chromatography, hydrophobic interaction chromatography, affinity chromatography, hydroxylapatite chromatography and lectin chromatography. Most preferably, high performance liquid chromatography (“HPLC”) is employed for purification.
Many expression systems are known, including systems employing: bacteria (e.g. E. coli and Bacillus subtillis ) transformed with, for example, recombinant bacteriophage, plasmid or cosmid DNA expression vectors; yeasts (e.g. Saccaromyces cerevisiae ) transformed with, for example, yeast expression vectors; insect cell systems transformed with, for example, viral expression vectors (e.g. baculovirus); plant cell systems transfected with, for example viral or bacterial expression vectors; animal cell systems transfected with, for example, adenovirus expression vectors.
The vectors include a prokaryotic replicon, such as the Col E1 ori, for propagation in a prokaryote, even if the vector is to be used for expression in other, non-prokaryotic cell types. The vectors can also include an appropriate promoter such as a prokaryotic promoter capable of directing the expression (transcription and translation) of the genes in a bacterial host cell, such as E. coli , transformed therewith.
A promoter is an expression control element formed by a DNA sequence that permits binding of RNA polymerase and transcription to occur. Promoter sequences compatible with exemplary bacterial hosts are typically provided in plasmid vectors containing convenient restriction sites for insertion of a DNA segment of the present invention.
Typical prokaryotic vector plasmids are: pUC18; pUC19, pBR322 and pBR329 available from Biorad Laboratories (Richmond, Calif., USA); pTc99A, pKK223-3, pKK233-3, pDR540 and pRIT5 available from Pharmacia (Piscataway, N.J., USA); pBS vectors, Phagescript vectors, Bluescript vectors, pNH8A, pNH16A, pNH18A, pNH46A available from Stratagene Cloning Systems (La Jolla, Calif. 92037, USA).
A typical mammalian cell vector plasmid is pSVL available from Pharmacia (Piscataway, N.J., USA). This vector uses the SV40 late promoter to drive expression of cloned genes, the highest level of expression being found in T antigen-producing cells, such as COS-1 cells. Examples of an inducible mammalian expression vectors include pMSG, also available from Pharmacia (Piscataway, N.J., USA), and the tetracycline (tet) regulatable system, available form Clontech. The pMSG vector uses the glucocorticoid-inducible promoter of the mouse mammary tumour virus long terminal repeat to drive expression of the cloned gene. The tet regulatable system uses the presence or absence of tetracycline to induce protein expression via the tet-controlled transcriptional activator.
Useful yeast plasmid vectors are pRS403-406 and pRS413-416 and are generally available from Stratagene Cloning Systems La Jolla, Calif. 92037, USA). Plasmids pRS403, pRS404, pRS405 and pRS406 are Yeast Integrating plasmids (YIps) and incorporate the yeast selectable markers HIS3, TRP1, LEU2 and URA3. Plasmids pRS413-416 are Yeast Centromere plasmids (YCps).
Methods well known to those skilled in the art can be used to construct expression, vectors containing the coding sequence and, for example appropriate transcriptional or translational controls. One such method involves ligation via homopolymer tails. Homopolymer polydA (or polydC) tails are added to exposed 3′ OH groups on the DNA fragment to be cloned by terminal deoxynucleotidyl transferases. The fragment is then capable of annealing to the polydT (or polydG) tails added to the ends of a linearised plasmid vector. Gaps left following annealing can be filled by DNA polymerase and the free ends joined by DNA ligase.
Another method involves ligation via cohesive ends. Compatible cohesive ends can be generated on the DNA fragment and vector by the action of suitable restriction enzymes. These ends will rapidly anneal through complementary base pairing and remaining nicks can be closed by the action of DNA ligase.
A further method uses synthetic molecules called linkers and adaptors. DNA fragments with blunt ends are generated by bacteriophage T4 DNA polymerase or E. coli DNA polymerase I which remove protruding 3′ termini and fill in recessed 3′ ends. Synthetic linkers, pieces of blunt-ended double-stranded DNA which contain recognition sequences for defined restriction enzymes, can be ligated to blunt-ended DNA fragments by T4 DNA ligase. They are subsequently digested with appropriate restriction enzyme to create cohesive ends and ligated to an expression vector with compatible termini. Adaptors are also chemically synthesised DNA fragments which contain one blunt end used for ligation but which also possess one pre-formed cohesive end.
Synthetic linkers containing a variety of restriction endonuclease sites are commercially available from a member of sources including International Biotechnologies Inc, New Haven, Conn., USA.
A desirable way to modify the nucleic acid molecule encoding the transglutaminase is to use the polymerase chain reaction as disclosed by Saiki et al (1988) Science 239, 487-491. In this method the nucleic acid molecule, e.g. DNA, to be enzymatically amplified is flaked by two specific oligonucleotide primers which themselves become incorporated into the amplified DNA. The said specific primers may contain restriction endonuclease recognition sites which can be used for cloning into expression vectors using methods known in the art.
Conveniently, the mammalian transglutaminase is a variant transglutaminase.
By “a variant” we include a polypeptide comprising the amino acid sequence of a naturally occurring mammalian transglutaminase wherein there have been amino acid insertions, deletions or substitutions, either conservative or non-conservative, such that the changes do not substantially reduce the activity of the variant compared to the activity of the activated naturally occurring mammalian transglutaminase. For example, the variant may have increased activity compared to the activity of the naturally occurring transglutaminase.
Alternatively, the variant may have increased ability to facilitate the colonisation of medical implants by cells, wherein said increased ability is independent of the enzyme activity of the variant but is related to some other property of the variant. For example, have increased ability of the variant transglutaminase to facilitate the colonisation of medical implants by cells may be associated with an increased ability to bind endogenous (i.e. host) proteins such as receptors.
The enzyme activity of variant mammalian transglutaminases may be measured by the biotin-cadaverine assay, as described in the Examples and as published in (Jones et al., 1997, J. Cell. Sci. 110, 2461-2472). For example, reduced expression of tissue transglutaminase in a human endothelial cell line leads to changes in cell spreading, cell adhesion and reduced polymerisation of fibronectin. Alternatively, transglutaminase activity may be measured by the incorporation of [ 14 C]-putrescine incorporation into N,N′-dimethylcasein, as outlined by Lorand et al., 1972, Analytical Biochemistry 50, 623. The increased ability of the variant enzyme to facilitate the adhesion and spreading of cells on medical implants may be measured by the methods disclosed herein.
Variant transglutaminases may be made using methods of protein engineering and site-directed mutagenesis commonly known in the art (for example, see Sambrook et al. (1989) Molecular Cloning, A Laboratory Manual , Second Edition, Cold Spring Harbor, N.Y.).
Preferably, the variant mammalian transglutaminase is an inactive tissue transglutaminase wherein its active site cysteine (e.g. Cys 277 of human tissue transglutaminase; see Gentile et al. 1992 supra and accession no. M 55153) is mutated to a serine residue.
Advantageously, the variant mammalian transglutaminase is a fragment of a naturally occurring tissue transglutaminase or Factor XIIIa which retains the ability of said naturally occurring transglutaminase to promote biocompatibility. The ability of transglutaminase fragments to promote biocompatibility may be determined by measuring the adhesion properties of such variant proteins, e.g. by coating artificial polymers with the variant enzyme(s), with or without precoating with fibronectin, and then investigating the ability of cells to attach to and spread on these coated polymers.
It will be appreciated by those skilled in the art that the medical implant materials of the invention may comprise naturally occurring polymers, synthetic polymers, co-polymers of such polymers, and blends thereof.
Preferably, the polymer is a naturally occurring polymer. More preferably, the polymer is a naturally occurring extracellular matrix molecule such as collagen, fibronectin, fibrin, fibrillin, glycosoaminoglycans, and hyaluronic acid.
Advantageously, the polymer is a synthetic polymer. More preferably, the polymer is a synthetic polymer selected from the group consisting of poly(ε-caprolactone) (PCL), poly( L -lactide) (PLA), poly(glycolide) (PGA), poly( DL -lactide co-glycolide) (PLG) and copolymers and blends thereof. Other synthetic polymers include methacrylates poly(ethylmethacrylate), ethylacrylate, tetrahydrofurfurylmethacrylate, hydroxyethylmethacrylate, silastic, poly(tetrafluoroethylene), medpore (porous polyethylene), poly(orthoester), and poly(dioxane).
Most preferably, the medical implant material comprises poly-(ε-caprolactone).
It will be appreciated that the polymers may be biodegradable or non-biodegradable. Preferably, the polymer is biodegradable. More preferably, the polymer is a biodegradable polymer which has a biodegradation rate that is the same as or slower than the rate of regeneration of the tissue for which the medical implant acts as a temporary replacement. Thus, the biodegradable polymer should be resorbed only after it has served its purpose as a scaffold for regeneration of new tissue. It will be further appreciated that the polymer and its degradation product(s) should be substantially non-toxic and non-inflammatory.
In the medical implant material according to the first aspect of the invention, the polymer provided is associated with a binding protein which binds a transglutaminase.
By a ‘binding protein’ we include a protein or polypeptide which is able to bind to a mammalian transglutaminase, i.e. a transglutaminase binding protein. Preferably, the transglutaminase binding protein binds to the mammalian transglutaminase with a binding affinity greater than 10 3 L/mol. More preferably, the affinity constant is greater than 10 4 L/mol, for example greater than 10 5 L/mol, 10 6 L/mol, 10 7 L/mol, 10 8 L/mol, 10 9 L/mol, 10 10 L/mol, or 10 11 L/mol.
Advantageously, the transglutaminase binding protein is or comprises a transglutaminase substrate.
By ‘a transglutaminase substrate’ we include a protein or polypeptide which comprises a transglutaminase substrate site.
Preferably, the transglutaminase binding protein is selected from a group of transglutaminase substrates of consisting fibronectin, fibrin, fibrinogen, collagen, entactin, osteonectin, osteopontin, thrombospondin, vitronectin, β-lactoglobulin and casein, or fragments thereof that are capable of binding to a transglutaminase.
More preferably, the transglutaminase binding protein is fibronectin or a fragment thereof that is capable of binding to a transglutaminase.
Most preferably, the transglutaminase binding protein is a human fibronectin fragment comprising the N-terminal fragment of fibronectin (i.e. amino acids 32-608) or fragments within this domain, for example the probable tTgase binding site (amino acids 229-273), the collagen binding site (amino acids 308-608) or the fibrin-Heparin binding site1 (amino acids 52-272) or combinations of these different fragments. From GenBank X02761 (Reference Kornblititt et al EMBO. J. (1985) 4, 1755-1759) for human fibronectin.
It will be appreciated by those skilled in the art that particular combinations of transglutaminase and transglutaminase binding protein may be preferred. For example, it may be preferable to use a tissue transglutaminase in combination with fibronectin (or a fragment thereof). Likewise, it may be preferable to use a plasma transglutaminase (e.g. Factor XIII) in combination with fibrin (or a fragment thereof) and fibronectin (or a fragment thereof). Additionally, the medical implant materials of the first aspect of the invention may comprise mixtures of different transglutaminases and transglutaminase binding proteins.
In the medical implant materials of the present invention, the polymer may be associated with the transglutaminase binding protein using methods known in the art. By ‘associated with’ we include a polymer which is coated, impregnated, covalently bound to or otherwise admixed with a transglutaminase binding protein.
Preferably, the polymer is coated with the binding protein. By ‘coated’ we mean that the transglutaminase binding protein is applied to the surface of the polymer. Thus, the polymer may be painted or sprayed with a solution comprising a transglutaminase binding protein. Alternatively, the polymer may be dipped in a reservoir of transglutaminase binding protein solution. Preferably, the polymer is pre-shaped to from the medical implant prior to being coated with a transglutaminase binding protein.
Advantageously, the polymer is impregnated with the binding protein. By ‘impregnated’ we mean that the transglutaminase binding protein is incorporated or otherwise mixed with polymer such that it is distributed throughout the medical implant material.
For example, the polymer may be incubated overnight at 4° C. in a solution comprising a transglutaminase binding protein. Alternatively, a transglutaminase binding protein may be immobilised on the polymer surface by evaporation or by incubation at room temperature.
In an alternative embodiment, the transglutaminase binding protein is covalently linked to the polymer, e.g. at the external surface of the polymer.
Thus, a covalent bond is formed between an appropriate functional group on transglutaminase binding protein and a functional group on the polymer support. Methods for covalent bonding of proteins to polymer supports fall into a number of sub-groups including covalent linking via a diazonium intermediate, by formation of peptide links, by alkylation of phenolic, amine and sulphydryl groups on the binding protein, by using a poly functional intermediate e.g. glutardialdehyde, and other miscellaneous methods e.g. using silylated glass or quartz where the reaction of trialkoxysilanes permits derivatisation of the glass surface with many different functional groups. For details, see Enzyme immobilisation by Griffin, M., Hammonds, E. J. and Leach, C. K. (1993) In Technological Applications of Biocatalysts (BIOTOL SERIES), pp. 75-118, Butterworth-Heinemann. See also the review article entitled ‘Biomaterials in Tissue Engineering’ by Hubbell, J. A. (1995) Science 13:565-576.
Once associated with the polymer, the transglutaminase binding protein may provide a means of linking the mammalian transglutaminase to the polymer.
The polymer associated with the binding protein may be treated with the mammalian transglutaminase using the same methods described above. Thus, the polymer (or medical implant material comprising said polymer) may be coated, impregnated, covalently bound to or otherwise admixed with a mammalian transglutaminase.
Preferably, the polymer is coated with a mammalian transglutaminase. For example, the polymer may be painted or sprayed with a solution comprising a transglutaminase. Alternatively, the polymer may be dipped in a reservoir of transglutaminase solution. More preferably, the polymer is coated with a transglutaminase immediately prior to implantation of the medical implant material into the human or animal host. For example, the polymer may be coated with the transglutaminase on the same day that the medical implant is to be used, for example about one hour before implantation.
Advantageously, the polymer is impregnated with a mammalian transglutaminase.
Conveniently, the polymer is covalently bound to a mammalian transglutaminase, either directly or indirectly via the binding protein.
It will be appreciated that the transglutaminase binding protein may be coated, impregnated, covalently bound to or otherwise admixed with the polymer at the same time as or prior to treating the polymer with a mammalian transglutaminase. Preferably, the polymer is associated with the binding protein prior to being treated with a mammalian transglutaminase.
In a preferred embodiment of the invention, there is provided a medical implant material comprising a polymer which is first coated with a transglutaminase binding protein and then coated with a mammalian transglutaminase.
In the medical implant materials according to the first aspect of the invention, the transglutaminase is provided in the absence of free divalent metal ions.
The presence of free divalent metal ions, e.g. Ca 2+ ions, plays a key role in the regulation of mammalian transglutaminase activity. Thus, absence of free divalent metal ions from the vicinity of the transglutaminase renders the enzyme substantially inactive in vitro.
By ‘in the absence of’ we include environments wherein the concentration of free divalent metal ions, such as Ca 2+ ions, is less than 10 μM. Preferably the concentration is less than 1 μM.
Preferably, the transglutaminase is provided in the absence of free Ca 2+ ions.
In a preferred embodiment of the first aspect of the invention, free divalent metal ions are reduced or eliminated from the vicinity of the transglutaminase by the inclusion in the medical implant material of a chelating agent.
For example, the medical implant materials may comprise a polymer that has been dipped in a solution comprising a transglutaminase and a chelating agent, such that the polymer is coated in the transglutaminase and chelating agent.
Preferably, the chelating agent is EDTA or EGTA.
More preferably, the medical implant material is provided with EDTA or EGTA at a concentration of between 5 mM and 0.1 M.
In yet another preferred embodiment of the first aspect of the invention, the medical implant material further comprises a reinforcing agent.
The reinforcing agent may be any substantially non-toxic material that can be blended or mixed with the polymer/transglutaminase components of the medical implant material to increase its strength.
Preferably, the reinforcing agent is selected from a group consisting of alumina, alumina-boria-silica, calcium metaphosphate glass fibres, titanium and carbon.
It will be appreciated by those skilled in the art that the medical implant materials of the invention may further comprise one or more additional polymer(s). Thus, there is provided a medical implant material comprising a copolymer or blended polymers and a mammalian transglutaminase.
Conveniently, the one or more additional polymer is a synthetic polymer.
Advantageously, the one or more additional polymer is a natural polymer.
Preferably, the one or more additional polymer is a natural polymer selected from the group consisting of collagen, fibronectin, fibrin, fibrillin, hyaluronic acid and glycosaminoglycans.
A second aspect of the invention provides the use of a mammalian transglutaminase in a method for improving the biocompatibility of a medical implant material, the method comprising the steps of:
(i) providing a medical implant material comprising with a polymer associated with a binding protein for binding the transglutaminase; and (ii) treating said material with a mammalian transglutaminase.
By ‘biocompatibility’ we mean the ability of the medical implant material to facilitate its colonisation by host cells and to enhance proliferation of host cells therein. Thus, biocompatibility is not intended to cover mere adhesion of host cells to the medical implant material, but rather relates to an interaction between the host cells and implant materials which permits colonisation to occur. In particular, biocompatibility includes the ability of said material to support cell attachment, cell spreading, cell proliferation and differentiation.
Biocompatibility of a medical implant material may be assessed using methods known in the art (see Examples). For example, increased biocompatibility of a medical implant material is associated with an increase in the ability of the material to facilitate cell attachment, cell spreading, cell proliferation and differentiation. In addition, the material should not induce any substantial loss in cell viability, i.e. via the induction of cell death through either apoptosis or necrosis. The differentiation of a cell type is measured in different ways depending on the cell type in question For example, for osteoblasts cells in culture, alkaline phosphate together with extracellular matrix (ECM) deposition, e.g. collagen 1, fibronectin, osteonectin and osteopontin, can be used as a marker. In addition, the ability of cells to proliferate and deposit ECM is important to ally material that is to be used as an implant, this includes endothdelial cells, chondrocytes and epithelial cells etc.
A preferred embodiment of the second aspect of the invention provides the use of a mammalian transglutaminase to facilitate colonisation of a medical implant material by host cells.
The mammalian transglutaminase for use in the second aspect of the invention pay be any transglutaminase described in relation to the first aspect of the invention. Preferably, the transglutaminase is a tissue transglutaminase. Advantageously, the transglutaminase is derived from human tissue or cells. Suitably, the transglutaminase is a recombinant transglutaminase. Conveniently, the transglutaminase is a variant transglutaminase.
The second aspect of the invention provides the use of a mammalian transglutaminase to improve the biocompatibility of any material comprising a polymer associated with a transglutaminase binding protein that may have utility in medical implants.
Preferably, the medical implant material is or comprises a polymer as defined above in relation to the first aspect of the invention.
Thus, the medical implant material may comprise a naturally occurring polymer, for example a naturally occurring polymer selected from the group consisting of extracellular matrix molecules such as collagen, fibronectin, fibrin, fibrillin glycosaminoglycans, and hyaluronic acid.
Alternatively, or in addition, the medical implant material may comprise a synthetic polymer, for example a polymer selected from the group consisting of poly(ε-caprolactone) (PCL), poly( L -lactide) (PLA), poly(glycolide) (PGA), poly( DL -lactide co-glycolide) (PLG) and co-polymers and blends thereof. Other synthetic polymers include methacrylates poly(ethylmethacrylate), ethylacrylate, tetrahydrofurfuryl-methacrylate, hydroxyethylmethacrylate, silastic, poly(tetrafluoro-ethylene), medpore (porous polyethylene), poly(orthoester), and poly(dioxane).
Preferably, the medical implant material is or comprises the polymer poly-ε-caprolactone).
In the use according to the second aspect of the invention, treatment of the medical implant material with a mammalian transglutaminase may comprise coating, impregnating, covalently linking or otherwise mixing the medical implant material with the transglutaminase.
Preferably, step (ii) comprises coating the medical implant material with a transglutaminase. In an alternative embodiment, step (ii) comprises impregnating the medical implant material with a transglutaminase. In a further embodiment, step (ii) comprises covalently linking the transglutaminase to the medical implant material (see above methods).
Advantageously, the step of treating the medical implant material with a transglutaminase is carried out in the absence of free divalent metal ions, such that the transglutaminase is substantially inactive in vitro.
For example, the step of treating the medical implant material with a transglutaminase is carried out in the presence of a divalent metal ion chelating agent, such as EDTA or EGTA.
In the second aspect of the invention, the medical implant material comprises a polymer associated with a transglutaminase binding protein. The polymer and binding protein may be associated in a variety of ways as described in relation to the first aspect of the invention.
As in the case of the first aspect of the invention, it will be appreciated by persons skilled in the art that certain combinations of transglutaminases and transglutaminase binding proteins may be preferentially used, for example a tissue transglutaminase with fibronectin (or a fragment thereof) or a plasma transglutaminase with fibrin (or a fragment thereof). Additionally, mixtures of different transglutaminases and transglutaminase binding proteins may be utilised.
A preferred embodiment of the second aspect of the invention provides the use of a mammalian transglutaminase to improve the biocompatibility of a medical implant material further comprising a reinforcing agent.
Advantageously, the reinforcing agent is selected from a group consisting of alumina, alumina-boria-silica, calcium metaphosphate glass fibres, carbon and titanium.
A further preferred embodiment of the second aspect of the invention provides the use of a mammalian transglutaminase to improve the biocompatibility of a medical implant material further comprising one or more additional polymer(s). Thus, the medical implant material may be a copolymer or a blend of polymers.
Conveniently, the one or more additional polymer is a synthetic polymer. Advantageously, the one or more additional polymer is a natural polymer. Preferably, the one or more additional polymer is a natural polymer selected from the group consisting of collagen, fibronectin, fibrin, fibrillin, hyaluronic acid and glycosaminoglycans.
In a preferred embodiment of the first or second aspect of the invention, the medical implant material is artificial bone.
The invention will now be described in detail with reference to the following figures and examples:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a photograph of the morphology of human osteoblast cells (HOBs) on PCL after 24 hours when seeded in 10% serum containing medium (viewed using light microscopy, original magnification was ×63).
FIG. 2 shows a photograph of the morphology of human osteoblast cells on PCL after 4 days when seeded in 10% serum containing medium (viewed using light microscopy, original magnification was ×63).
FIG. 3 shows a photograph of the morphology of human osteoblast cells on tissue culture plastic after 24 hours when seeded in 10% serum containing medium (viewed using light microscopy, original magnification was ×63).
FIG. 4 shows a photograph of the morphology of human osteoblast cells on tissue culture plastic after 4 days when seeded in 10% serum containing medium (viewed using light microscopy, original magnification was ×63).
FIG. 5 shows the standard curve for the binding of fibronectin to poly(ε-caprolactone) (PCL) as measured using the ELISA technique (see Examples) The fibronectin was immobilised by evaporation overnight at room temperature (see section 2.4.2 for details). Data represent mean values +/−S.D. (n=3).
FIG. 6 shows the standard curve for the binding of tissue transglutaminase to fibronectin coated poly(ε-caprolactone) (PCL) as measured using the ELISA technique (see Examples). The tTG was immobilised by evaporation overnight at room temperature (see section 2.4.2. for details). Data represent mean values +/−S.D., (n=3).
FIG. 7 shows the standard curve for the binding of tissue transglutaminase to fibronectin coated poly(ε-caprolactone) as measured using the ELISA technique (see Examples). The tTG was immobilised onto the surface for 1 hour at room temperature (see section 2.4.3. for details). Data represent mean values +/−S.D. (n=3).
FIG. 8 shows the quantitative evaluation of the activity of tTG when immobilised onto PCL in solution with fibronectin (FN) overnight at 4° C., using the biotin-cadaverine incorporation (see Examples). A comparison with immobilisation on tissue culture plastic is also shown. HB equals buffer containing 5 mN Tris-HCl (pH 7.4), 0.25 M sucrose, 3.85 mM DTT. Calcium is added at a concentration of 5 mM and EDTA at a concentration of 5 mM. Data represent mean values +/−S.D. (n=3). Statistical analysis using one way analysis of variance (Anova) was performed on the data (**=P<0.01 and ns=not significantly different).
FIG. 9 shows the quantitative evaluation of the activity of tTG when immobilised onto fibronectin coated PCL by evaporation, using the biotin-cadaverine assay (see Examples). A comparison with immobilisation on tissue culture plastic is also shown. Data represent mean values +/−S.D. (n=3). Statistical analysis using one way analysis of variance (Anova) was performed on the data (**=P<0.01 and ns=not significantly different).
FIG. 10 shows the quantitative evaluation of the activity of tTG when immobilised onto fibronectin coated PCL by incubation at room temperature for one hour, using the biotin-cadaverine assay (see Examples). Data represent mean values +/−S.D. (n=3). Statistical analysis using one way analysis of variance (Anova) was performed on the data (***=P<0.001, **=P<0.01, *=P<0.05 and ns=not significantly different).
FIG. 11 shows a micrograph of human osteoblast cells on PCL in serum free medium, 30 minutes after cell seeding (viewed using E.S.E.M.). The cells are all rounded in morphology on the biomaterial surface.
FIG. 12 shows a micrograph of human osteoblast cells in serum free medium on PCL coated with fibronectin, 30 minutes after cell seeding (viewed using E.S.E.M.). The cells have attached to the biomaterial and some cells have started to spread.
FIG. 13 shows a micrograph of human osteoblast cells in serum free medium on PCL coated with fibronectin and tissue transglutaminase, 30 minutes after cell seeding (viewed using he E.S.E.M.). The cells have attached and the majority are well spread having a flat morphology.
FIG. 14 shows a micrograph of human osteoblast cells in serum conning medium on tissue culture plastic, 30 minutes after cell seeding (viewed using E.S.E.M.). The cells have attached and have started to spread slightly.
FIG. 15 shows a micrograph of human osteoblast cells on PCL in serum free medium, 60 minutes after cell seeding (viewed ling E.S.E.M.). The cells have attached to the PCL are starting to spread slightly.
FIG. 16 shows a micrograph of human osteoblast cells in serum free medium on PCL coated with fibronectin, 60 minutes after cell seeding (viewed using E.S.E.M.). The results show a mixed morphology of rounded, slightly spread and flattened cells.
FIG. 17 shows a micrograph of human osteoblast cells in serum free medium on PCL coated with fibronectin and tissue transglutaminase, 60 minutes after cell seeding (viewed using E.S.E.M.). All the cells have spread and are flat in morphology on this particular surface.
FIG. 18 shows a micrograph of human osteoblast cells in serum containing medium on tissue culture plastic, 60 minutes after cell seeding (viewed using E.S.E.M.). The cells have started to spread and some cells are flat in morphology.
FIG. 19 shows a micrograph of human osteoblast cells on PCL in serum free medium, 3 hours after cell seeding (viewed using E.S.E.M.). The cells are all rounded in morphology. Some of the cells detached from the surface.
FIG. 20 shows a micrograph of human osteoblast cells in serum free medium on PCL coated with fibronectin, 3 hours after cell seeding (viewed using E.S.E.M.). The cells are all flat in morphology and form a monolayer over the surface of the biomaterial.
FIG. 21 shows a micrograph of human osteoblast cells in serum free medium on PCL coated with fibronectin and tissue transglutaminase, 3 hours after cell seeding (viewed using E.S.E.M.). The cells are all flat in morphology, forming a complete monolayer on the surface of this biomaterial.
FIG. 22 shows HOB cell spreading on Poly(ε-caprolactone) (PCL) when coated with either fibronectin(FN) or fibronectin+tissue transglutaminase (N+tTG) 30 minutes after cell seeding. The cells were scored type I-III (type I being cells that have just attached and type III being cells in the late stage of spreading). These results were all compared to tissue culture plastic (TCP) with (+) and without (−) serum in the medium which were used as the positive and negative controls respectively.
FIG. 23 shows human osteoblast cell spreading on Poly(ε-caprolactone) (PCL) when coated with either fibronectin(PN) or fibronectin+tissue transglutaminase (FN+tTG) 60 minutes after cell seeding. The cells were scored type I-III (type I being cells that have just attached and type III being cells in the late stage of spreading). These results were all compared to tissue culture plastic (TCP) with (+) and without (−) serum in the medium which were used as the positive and negative controls respectively.
FIG. 24 shows the proliferation of HOBs on tissue culture plastic over 8 days, using various amounts of foetal calf serum in the medium. Cell numbers were analysed by measurement of total DNA using the method as described in section 2.9.1.1. The data represent mean values +/−S.D. (n=4). The results were statistically analysed using the t test.
FIG. 25 shows the proliferation of human osteoblast cells on PCL in DMEM containing different amounts of foetal calf serum was investigated using the DNA Hoechst assay. The data represent mean values +/−S.D. (n=3), The results were analysed using one way analysis of variance (Anova) (**=P<0.01, *=P<0.05 and ns=not significantly different).
DETAILED DESCRIPTION OF THE INVENTION
EXAMPLES
Materials and Methods
Poly(ε-Caprolactone) Disc Preparation
Poly(ε-caprolactone)(PCL)(PCL650; Solvay Interox) was purchased in pellet form and pressed in a square cavity at a temperature above melting point, in order to form a 4 mm thick meet. PCL discs (6 mm in diameter) were then stamped from the polymer sheet using a cork borer and sterilised under UV light for 1 hour each side prior to use.
Cell Culture
Human Osteoblast (HOB) cells were isolated from explants of trabecular bone dissected from femoral heads following orthopaedic surgery (as described by DiSilvio, 1995). All cells were cultured in vitro using Dulbecco's Modified Eagles Medium (DMEM). This was supplemented with 10% foetal calf serum, 1% non-essential amino acids, 150 μg/ml ascorbic acid (BDH, Poole, U.K.), 2 mM L-Glutarine, 0.02M [4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid], (HEPES), 1% Penicillin/Streptomycin (all obtainable from Gibco, BRL, Paisley, U.K.). The cells were incubated at 37° C. in 5% CO 2 , 95% air.
Visualisation of Human Osteoblasts Cells on PCL Over 4 Days Using the Toluidine Blue Stain and Transmission Electron Microscopy (T.E.M)
HOB cells were grown on the PCL in 10% serum containing DMEM to initially assess the interaction of cells with this particular polymer surface. The toluidine blue stain allowed the attachment, spreading and proliferation of the cells-on the PCL to be observed. T.E.M. allowed the ultra structure of the cells to be observed on the biomaterial. Both these techniques would indicate whether the polymer is biocompatible with this particular cell type.
Toluidine Blue
PCL discs were placed in a 96 well plate (3 replicates per sample) and human osteoblast cells (HOBs) were seeded onto the biomaterial in 10% serum containing DMEM at a density of 1.7×10 5 /cm 2 . Tissue culture plastic (TCP) was used as a positive control surface. The plate was then incubated at 37° C. in 5% CO 2 . At days 1 and 4 after cell seeding the medium was removed and the cells were washed in sterile phosphate buffered saline (PBS). The cells were fixed in 4% paraformaldehyde and 2% sucrose for five minutes at room temperatue and then washed twice in PBS. The cells were stained with 1% toluidine blue diluted in sterile PBS for five minutes at room temperature. The samples were then washed several times in PBS and viewed using light microscopy (Olympus SZ-PT).
Transmission Electron Microscopy (T.E.M.)
PCL discs were placed in a 48-well plate (3 replicates per time point) and HOB cells were seeded onto the biomaterial in 10% serum containing DMEM at a density of 1.7×10 5 /cm 2 . Thermanox was used as a positive control spice. The plate was then incubated at 37° C. in 5% CO 2 . At days 1, 2, 4 and 8 days after cell seeding, the medium was removed and the cells were washed in sterile PBS. The samples were fixed overnight in 1.5% glutaraldehyde in 0.1 M sodium cacodylate buffer (pH 7,4) then washed in the same buffer and secondary fixed using 1% osmium tetroxide in Millonig's buffer for 1 hour. The samples were washed in buffer followed by a dehydration step through a series of alcohols, 50%, 70%, 90%, 96% and 100% with two 10-minute changes for each alcohol and 30 minutes in 100% alcohol. Araldite CY212 resin was added to give a ratio 3:1 with alcohol, fixed for 1 hour and then transferred to a 1:1 resin:alcohol mixture and left overnight and then placed in pure resin for 2 hours under vacuum inltration. The pure resin was changed twice (2 hours each change) and then made into blocks. The polymers were then embedded and cured at 45° C. in an oven for 48 hours (this temperature was used to prevent the PCL from melting). Ultra thin sections were then cut using a Reichert Ultracut E Ultramicrotome, collected on copper grids and stained with 3% Uranylacetate in 50% methanol for 6 minutes and then Reynold's lead citrate for 6 minutes. The samples were examined using a Philips EM410 transmission electron microscope at 80 kV.
Guinea-Pig Liver Tissue Transglutaminase Type II Immobilisation onto PCL
Guinea-pig liver tissue transglutaminase (i.e. type II transglutaminase, tTG) obtainable from Sigma was immobilised onto PCL using three methods as shown below. Each method uses the idea of immobilising the tTG to the PCL via fibronectin because fibronectin has a tTG binding site. The tTG does not have to be active to bind to fibronectin (i.e. calcium ions are not required). Ethylenediaminetetraacetic acid (EDTA) was added to the tTG to keep the enzyme in its inactive form and prevent the enzyme from cross-linking the fibronectin or itself during the immobilisation. The tTG could be added to the PCL in drop form because the surface of the PCL was hydrophobic. A quantity of 60 μl was enough to cover the whole surface, forming a meniscus on the surface.
(i) Immobilisation at 4° C.
A solution of 15 μg/ml bovine plasma fibronectin (Gibco) and 10 μg/ml tissue transglutaminase (tTG) in 0.1M EDTA (pH 7.4.), was added to the sterile PCL discs (60 μl per disc). This was then left overnight at 4° C. After incubation, the solution was removed and the PCL was washed three times with 0.1M Tris-HCl (pH 7.4.), 5 minutes each wash. The discs were then transferred to the tissue culture plates.
(ii) Immobilisation by Evaporation Overnight
A 60 μl aliquot of 30 μg/ml bovine plasma fibronectin in sterile distilled water was added to each sterile PCL disc and left overnight in the tissue culture hood to evaporate. Once the water had evaporated, a 60 μl aliquot of 20 μg/ml tissue transglutaminase in 5 mM EDTA (pH 7.4.) was added to the PCL. This was left to evaporate overnight in the tissue culture hood and then the discs were washed three times in 0.1M Tris-HCl (pH 7.4.), 5 minutes each wash. The discs were then transferred to the tissue culture plates.
(iii) Immobilisation by Incubation at Room Temperature
A 60 μl aliquot of 30 μg/ml bovine plasma fibronectin in sterile distilled water was added to each sterile PCL disc and left overnight in the tissue culture hood to evaporate. Once the water had evaporated, a 60 μl aliquot of 20 μg/ml tissue transglutaminase in 5 mM EDTA (pH 7.4.) was added to each PCL disc. This was then left for one hour at room temperature. The tTG solution was removed and then the discs were washed three times in 0.1M Tris-HCl (pH 7.4.), 5 minutes each wash and transferred to the tissue culture plates.
ELISA for Fibronectin
PCL discs were coated with different concentrations of fibronectin (0 to 50 μg/ml) by the evaporation technique described above. The fibronectin was detected using the fibronectin ELISA assay (Gaudry, 1998). The polymers were initially washed in 3×100 μl of PBS and then blocked with 100 μl of 3% w/v bovine serum albumin (BSA) in PBS. The plate was incubated for 1 hour at room temperature and then washed with 3×100 μl of PBS before the addition of 100 μl of the primary antibody (polyclonal rabbit anti-human plasma fibronectin, diluted 1:5000 in blocking buffer). The plate was incubated for 2 hours at room temperature, then washed in 3×100 μl of PBS before the addition of 100 μl of the secondary antibody (HRP conjugated goat anti-rabbit, diluted 1:5000 in blocking buffer). The plate was incubated for 1 hour at room temperature and then rinsed in 3×100 μ 1 of before the addition of 100 μl of 0.1M sodium acetate. The HRP was detected using 100 μl of the developer (20 mls NaOAc, 150 μl TMB and 10 μl H 2 O 2 ) and the reaction stopped with 50 μl of 2.5M H 2 SO 4 . The results were then read in a colourimeter (Titertek Multiskan MCC/340MK2) at a wavelength of 450 nm.
Fibronectin-ELISA for Tissue Transglutaminase
The ELISA used to detect tTG was a modification of that developed by Achyuthan et al., (1995). This relies upon the ability of tTG to bind specifically to immobilised plasma fibronectin.
PCL discs were coated with 60 μl of 30 μg/ml fibronectin in sterile distilled water and then different concentrations of tTG (0-50 μg/ml) using the two different methods as described above. The discs were washed in 3×100 μl of PBS and then blocked with 100 μl of 3% w/v BSA in PBS for 1 hour at room temperature. The PCL discs were rinsed with 3×100 μl of PBS and bound tTG was detected using 100 μl of anti-monoclonal antibody CUB7402 (diluted 1:1000 in blocking buffer). The primary antibody was left on the polymers for 2 hours at room temperature and then washed in 3×100 μl of PBS prior to the addition of 100 μl of the secondary antibody (HRP-conjugated goat-anti-mouse IgG (Sigma) diluted 1:5000 in blocking buffer). This was left for 1 hour at room temperature and then the HRP detected (as described above).
To Determine if tTG is in its Active Form when Immobilised on the PCL Surface
To determine if fibronectin and tTG are present on the surface of PCL, the biotin-cadaverine assay was used, (Jones et al., 1997). This method also allows the activity of tTG on the surface of the biomaterial to be quantified.
Four tissue culture plastic (TCP) wells and 4 PCL discs were coated with fibronectin as described above (3 replicates per sample were used). For one of the fibronectin coated PCL samples, tTG was immobilised onto the PCL surface using either of the three different methods also described above. After washing the fibronectin/tTG coated PCL in 3×100 μl of 0.1M Tris-HCl (pH, 7.4.), 100 μl of homogenising buffer consisting of 0.25 mM sucrose, 5 mM Tris-HCl (pH 7.4.) and 2 mM EDTA (H 7.4.) was added and incubated for different time periods up to 15 hours at 37° C. This was then tested for tTG activity. The other three fibronectin coated PCL discs were used for controls, which consisted of adding tTG in directly homogenising buffer containing either calcium (positive control) or EDTA (negative control). The other negative control was homogenising buffer only. The four TCP wells coated with fibronectin were to enable tTG activity to be analysed in the homogenising buffer taken from the fibronectin/tTG coated PCL surface and for three controls which are the same as mentioned above.
The PCL or TCP were initially blocked with 100 μl of 3% BSA in 0.1M Tis-HCl (pH 7.4.) at room temperature for 1 hour and then washed with 3×100. μl of 0.1M Tris-HCl. For the positive controls, 100 μl of the following solution was added to the fibronectin coated TCP and PCL: 20 μg/ml guinea pig tTG, 5 mM CaCl 2 , 3.85 mM DTT and 0.4% biotin-cadaverine in homogenising buffer. For the negative controls 100 μl of the following solution was added to the fibronectin coated TCP and PCL: 20 μg/m guinea pig tTG, 5 mM EDTA, 3.85 mM DTT and 0.4% biotin-cadaverine in homogenising buffer. To rule out any biomaterial interaction with the assay, another control was used which consisted of adding the following solution to fibronectin coated PCL and TCP: 5 mM CaCl 2 , 3.85 mM DTT and 0.4% biotin-cadaverine in homogeising buffer. This was also added to the fibronectin and tTG coated PCL. To the 100 μl of homogenising buffer that had been incubated with the immobilised fibronectin/tTG surface, 10 mM CaCl 2 , 3.85 mM DTT and 0.4% BC was added.
The samples were then left for 2 hours at 37° C. After this time 100 μl of 5 mM EDTA in 0.1M Tris-HCl was added to the wells, left for 10 minutes and then washed in 2×100 μl of 0.1M Tris-HCl. 100 μl of extravidin peroxidase in 3% BSA was added (1:5000 dilution) and left at 37° C. for 1 h. The wells were washed with 3×100 μl of 0.1M Tris-HCl and 100 μl of 0.1M NaOAc (pH 6.0). 100 μl of the developer was added (20 mls NaOAc, 150 μl TMB and 10 μl H 2 O 2 ) and the reaction stopped with 50 μl of 2.5M H 2 SO 4 . The results were then read in a colourimeter at a wavelength of 450 nm.
To Determine the Effect Tissue Transglutaminase has on the Spreading of Human Osteoblast Cells on Poly(ε-Caprolactone)
Initially sterile PCL discs were coated with fibronectin and tTG as described above. Controls consisted of PCL, PCL coated with fibronectin and TCP. The HOB cells were harvested using trypsin, followed by blocking in serum containing medium and then resuspended twice in serum free medium. Cells were seeded onto the samples at 3.4×10 5 cells/cm 2 in serum free medium. Cells were also seeded onto TCP in serum continuing medium (positive control surface). All samples were done in triplicate.
Scanning Electron Microscopy
At 1, 2, 4 and 6 hours, the samples were washed twice with PBS and fixed in 1.5% paraformaldehyde in sodium cocodylate buffer for 30 minutes at room temperature. The samples were dehydrated in a graded series of ethanol (60-100%) and then left to evaporate in hexomethyldisiazane (HMDS) overnight. The samples were then gold coated and viewed using a Philips 501B scanning electron microscope.
Environmental Scanning Electron Microscopy
At 30 minutes, 1 hour and 3 hours the samples were washed in 2×200 μl of PBS and fixed in 200 μl of 1.5% paraformaldehyde in 0.1M sodium cocodylate buffer (pH 7.4.) for 30 minutes at room temperature. The cells were then washed in 2×200 μl of sterile double distilled water and viewed using a Philips XL 30 environmental scanning electron microscope equipped with a field emission gun (FEG-ESEM) in wet mode. The degree of cell spreading was scored as type I-III (Sinha et al., 1994).
To Determine the Effect Tissue Transglutaminase has on the Differentiation of Human Osteoblast Cells on Poly(ε-Caprolactone)
(i) Determination of the Minimum Amount of Foetal Calf Serum in DMEM Required to Stimulate Human Osteoblast Cell Proliferation on PCL
Initially, the minimum amount of foetal calf serum (FCS) in the medium required to stimulate HOB cell proliferation was determined. The cells were harvested using trypsin, followed by blocking in serum containing medium and then resuspended twice in serum free medium. The cells were then seeded into a 96 tissue culture plate (Falcon) in either, 100 μl of 0%, 2%, 4%, 6% or 10% FCS at a density of 1.7×10 5 cells/cm 2 . The negative control used. consisted of medium without cells, and the positive control consisted of cells in 10% serum containing medium. The cells were incubated at 37° C., 5% CO 2 for either 1, 2, 4, 6 or 8 days. At each of these time points the medium was removed from the wells and the cells washed in 2×100 μl of sterile PBS. 100 μl of sterile double distilled water was added to each well and the cells lysed by the freeze thaw method, which involved placing the samples at −80° C. for 20 minutes and then at 37° C. for 15 minutes. This was repeated three times. The DNA content of each sample was determined using the DNA Hoechst assay (Rago et al., 1990) (see below).
The above experiment was repeated using PCL instead of TCP, however 7% and 10% FCS in the medium was used and the cells were incubated for either 1 or 3 days. The negative control consisted of medium without cells. The positive control consisted of cells in 10% serum containing medium on TCP.
(ii) DNA Hoechst Assay (Rago et al., 1990)
This assay allows cellular DNA content to be Wed using the fluorochrome; bisbenzimidazole (Hoechst 33258; Sigma). It works by a shift in the emission wavelength of Hoechst 33258 upon binding of cellular DNA. This results in a linear relationship between fluorescence and DNA content over a broad range of DNA. This reaction has been shown to be highly specific, and other cellular contents such as RNA, protein and carbohydrates do not cause significant fluorescence.
Hoechst 33258 was dissolved in sterile deionised water to a final concentration of 1 mg/ml and then diluted 1 in 50 with TNE buffer (pH 7.4.). TNE buffer consisted of 10mM Tris (BDH), 2 mM Sodium Chloride (Sigma) and 1 mM diaminoethanetetra-acetic acid (EDTA) (Fisons). It has previously been shown that crude cellular extracts assayed in the presence of high salt concentrations (as in the TNE buffer) yield higher fluorescence due to dissociation of DNA and chromatin with improved exposure of DNA binding sites.
100 μl of the diluted Hoechst 33258 was then added to 100 μl of the cell lysates along with a range of positive DNA calf thymus standards (range 0-20 μg/ml) (obtainable from Sigma). The fluorescence was then read at 360 nm (excitation filter) and 460 nm (emission filter) using a CytoFluor™ fluorescent plate reader (Millipore).
(iii) The Differentiation of Human Osteoblast Cells on the Fibronectin/Tissue Transglutaminase Coated PCL Using the Alkaline Phosphatase Assay
The sterile PCL discs were coated with fibronectin and tTG as described in section 2.4.3. Controls consisted of PCL, PCL coated with FN and also TCP. The HOB cells were harvested using trypsin, followed by blocking in serum containing medium and then resuspended twice in serum free medium. Cells were seeded onto the polymers and TCP at 1.7×10 5 cells/cm 2 in 10% serum containing medium. The cells were incubated for 2 days at 37° C., 5% CO 2 . After this dime period, the medium was removed, 100 μl of PBS added and then 100 μl of sterile distilled water added. The cells were lysed using the freeze thaw method, whereby the cells were frozen at −80° C. for 20 minutes and then thawed for 15 minutes at 37° C. (this was repeated three times). The samples were then diluted 1 in 2 with sterile double distilled water. The DNA Hoechst assay (see above) and the Alkaline Phosphatase assay were then performed on the cell lysates (see below).
(iv) Alkaline Phosphatase (ALP) Assay (Granutest Kit Obtainable from Merck)
Alkaline phosphatase (ALP) is a marker of early bone cell differentiation. This photometric assay allows ALP activity to be quantified. The principle of the assay is the conversion of 4-Nitrophenylphosphate (substrate) and water to phosphate and 4-Nitrophenolate in the presence of active ALP.
Twenty-five ml of buffer (pH 9.8) (containing 1.0 mol/l diethanolamine, 0.5 mmol/l MgCl 2 and 0.225 mol/l NaCl) was added to 0.35 g of the substrate (consisting of 255 μmol 4-Nitrophenylphosphate). 50 μl of this solution was then added to 50 μl of the cell lysate sample and the absorbance read in a cytofluorimeter (Anthos Labtec Instruments) at 450 nm (measuring filter) and 620 nm (reference filter).
Results
Human Osteoblast Morphology on Poly(ε-Caprolactone (PCL)
Human osteoblast cells were grown on the PCL in 10% serum containing DMEM to initially assess the interaction of cells with this particular polymer surface. Toluidine blue staining allowed the attachment, spreading and proliferation of the cells on the PCL. to be observed. Transmission electron microscopy (T.E.M.) allowed the ultra structure of the cells to be observed in order to assess their response to the biomaterial surface. This would give an indication as to whether the polymer is biocompatible with this particular cell type.
FIGS. 1 and 2 show HOB cells stained with toluidine blue at days 1 and 4 on PCL respectively. FIGS. 3 and 4 show HOB cells stained with toluidine blue at days 1 and 4 on TCP respectively. These results clearly indicate that HOB cells attach and spread on the PCL in DMEM containing 10% foetal calf serum as compared to the positive control (TCP). There is also a definite increase in cell population from day 1 to day 4 on both the TCP and PCL surfaces.
The T.E.M. results also indicated that the HOB cells proliferate on the PCL surface as shown by multilayer formation over time. The ultra structure of HOB cells on PCL was seen to be normal. However at 8 days of culture in DMEM containing 10% foetal calf serum, it was found that very few cells remained on the surface. It was thought that the cells must have been removed during the washing processes.
The Detection of Fibronectin and Tissue Transglutaminase (tTG) on PCL
The ELISA technique clearly demonstrated the binding of fibronectin to PCL (see FIG. 5 ) The concentration of bound fibronectin increased proportionally up to 50 μg/ml.
The modified ELISA technique also demonstrated the binding of tTG to fibronectin coated PCL when tTG was immobilised by either evaporation overnight or by incubation for 1 h at room temperature (see FIGS. 6 and 7 respectively). FIGS. 6 and 7 clearly show that tTG can be immobilised to PCL using both methods. The maximum concentration of tTG that can be immobilised to the fibronectin coated PCL is approximately 30 μg/ml for both immobilisation techniques and the half maximum binding capacity is approximately 15 μg/ml.
The Activity of Tissue Transglutaminase, After Immobilisation onto the Biomaterial Surface
(i) Quantitative Evaluation of the Activity of tTG on PCL when Immobilised in a 0.1M EDTA solution together with Fibronectin by Incubation at 4° C.
The activity of tTG on the PCL surface was evaluated using the biotin-cadaverine incorporation assay (see above). 15 μg/ml of fibronectin and 10 μg/ml tTG were immobilised onto the PCL ice by incubation together in a 0.1M EDTA solution overnight at 4° C. The data in FIG. 8 show that tTG is not active on the PCL surface or in the homogenising buffer removed from the same surface. This suggests that either fibronectin was not immobilised onto the PCL using ibis method (which needs to be confirmed using the ELISA technique) or the fibronectin adsorbed to the PCL was in a configuration unfavourable for tTG cross-linking. The positive control for PCL showed no significant tTG activity either, which again suggests that fibronectin is not present on the surface or is inaccessible for tTG cross-linking due to its unfavourable configuration. Another alternative would be that tTG did not bind to the fibronectin and was in an inactive form hence no activity was seen in the homogenising buffer either.
In further experiments the fibronectin and tTG concentrations were increased. It was also thought that 0.1M EDTA solution was too high a concentration for tTG binding as EDTA at this concentration might interfere with the tTG binding site on fibronectin molecule. Five mM EDTA was used in the preceding experiments (which is commonly used in the biotin cadaverine incorporation assay because it is high enough to inhibit tTG activity and yet low enough to allow the tTG to bind to the fibronectin).
(ii) Quantitative Evaluation of the Activity of tTG on Fibronectin-coated PCL When Immobilised by Evaporation in 5 mM EDTA.
The activity of tTG on the PCL surface was evaluated using the biotin-cadaverine incorporation assay (see above). The tTG was immobilised onto the PCL by initially coating the surface with 30 μg/ml fibronectin by evaporation. A 5 mM solution of 20 μg/ml tTG was then added to the PCL in the same way (see above for details). The data in FIG. 9 show that the evaporation method allows the fibronectin to be immobilised onto the PCL in a configuration that is favourable for tTG cross-linking (see PCL-positive control, which shows that addition of tTG gives rise to biotin cadaverine incorporation on the fibronectin coated PCL surface. The presence of, fibronectin on the PCL surface when immobilised by this method was also confirmed by the ELISA assay (see FIG. 5 ). FIG. 9 also illustrates that the immobilised tTG is not active on the PCL when it is immobilised by evaporation overnight even though the ELISA results show that it is present on the surface (see FIG. 6 ). There was no significant tTG activity in the homogenising buffer which was removed from the fibronectin/tTG PCL surface, which also confirms that the tTG is present on the surface of the polymer.
(iii) Quantitative Evaluation of the Activity of tTG on Fibronectin-coated PCL When Immobilised by Incubation in 5 mM EDTA for One Hour at Room Temperature
The activity of TG on the PCL surface was evaluated using the biotin-cadaverine incorporation assay (see section 2.7 for details). The tTG was immobilised onto the PCL by initially coating the surface with 30 μg/ml fibronectin by evaporation. A 5 mM solution of 20 μg/m tTG was then added to the PCL for 1 hour at room temperature (see above for details). FIGS. 9 and 10 both show that the evaporation method allows the fibronectin to be immobilised onto the biomaterial surface in a configuration that is favourable for tTG crossing (see PCL positive control, which shows that addition of tTG gives rise to biotin cadaverine incorporation on the fibronectin coated PCL. FIG. 10 also illustrates that immobilised tTG is present on the biomaterial surface and is active when immobilised for 1 h at room temperature. The ELISA technique (see FIG. 7 ) confirms that the tTG can be immobilised by this method. The homogenising buffer that was removed from the PCL that had previously been coated with fibronectin and tTG, showed no tTG activity when compared to the TCP negative control which confirms that tTG was immobilised to the PCL.
Human Osteoblast Cell Spreading on the Tissue Transglutaminase/Fibronectin Coated PCL:
HOB cells on tissue culture plastic (TCP) with and without 10% senum in the medium and PCL, PCL+fibronectin and PCL+fibronectin+tTG in serum free medium were cultured for 2 or 4 hours. After this, they were fixed and viewed using sa g electron microscopy (S.E.M.). The results clearly demonstrated that cell spreading occurred before 2 hours on the fibronectin/tTG coated PCL surface. Some distortion of the PCL surface occurred during the hydration step during S.E.M. sample preparation. The experiment was therefore repeated using smaller time points and viewed using environmental scanning electron microscopy (E.S.E.M.), which doesn't require a hydration step when preparing the sample. The samples were viewed in wet mode and the results are shown in FIGS. 11-21 .
FIGS. 11-14 shows the degree of spreading of HOBs on various substrates at 30 minutes after cell seeding. The results clearly show that in 30 minutes the cells have attached and spread to the fibronectin/tTG coated PCL surface. Some of the cells are already at the late stages of cell spreading. The rate at which these cells spread was quicker than cells seeded on TCP in serum containing medium or on tie fibronectin coated PCL surface. It can be clearly seen that cells on PCL alone are rounded in morphology and show no signs of spreading at this particular time point.
After 1 hour incubation on the different surfaces, similar results were obtained (see FIGS. 15-18 ). The cells were spreading quicker on PCL coated with fibronectin+tTG than on fibronectin coated PCL or TCP. The cells on the fibronectin+tTG coated PCL, showed a more flattened morphology than seen at 30 minutes. Cells on PCL still remained rounded at this time point.
FIGS. 19-21 show the degree of spreading 3 hours after seeding the HOB cells in serum free medium. The cells clearly remained rounded in morphology on the PCL. A lot of cells had detached from the biomaterial surface illustrating that HOB cells require adhesion proteins to spread on PCL. However, after 3 hours on the PCL+fibronectin and PCL+fibronectin+tTG surfaces the cells were flat in morphology and had formed a monolayer.
FIGS. 22 and 23 show graphical data to summarise the effects tTG has on HOB cell spreading after 30 and 60 minutes (as viewed using E.S.E.M.). The degree of cell spreading was scored as type I-III. Type I was classed as cells that have attached to the surface but remain rounded in morphology. Type II cells are classed as cells that have attached to the surface and have started to spread. Type III cells are classed as those which have attached and spread out flat on the surface (late stage of spreading).
It can therefore be concluded from FIGS. 16-23 that HOB cells respond immediately to the tTG on the PCL surface, which subsequently causes earlier cell spreading. This surface is far more preferential to PCL alone or PCL coated with fibronectin.
Human Osteoblast Cell Differentiation on the Tissue Transglutaminase/Fibronectin-coated PCL
Initially the minimum serum content of medium required for HOB cells to proliferate on TCP was investigated. The intention was to allow minimal interference of serum proteins with tTG when investigating its role in the differentiation of HOB cells when coated on PCL. FIG. 24 clearly shows that HOB cells cannot proliferate in serum free medium on TCP.
They can proliferate with as little as 2% serum im the medium. However the rate of proliferation is significantly slower than that of cells in the medium with a serum content of 4% or more.
When the proliferation of HOB cells on PCL in varying amounts of serum containing medium was studied, it was found that a much higher serum content was required (see FIG. 25 ). There was no significant difference in DNA concentration between day 1 and day 3 when the cells were cultured in 7% serum cont medium. However, the DNA concentration was significantly higher between day 1 and day 3 for cells cultured in 10% serum containing medium. These results illustrate that the minimum content of serum in DMEM required for HOB cell proliferation on PCL, is 10%. At day 3, the number of cells on tissue culture plastic was significantly greater than the number of cells on PCL when both are cultured in 10% serum contating medium.
Discussion
The study of implant surface and biomaterial tissue interface reactions is essential for the continued improvement of implant performance. A review by Blitterwijk et al., (1991) discusses the importance of the reactions of cells at implant surfaces in determining the biocompatibility of the implant. Current research involves making bioactive materials, which will allow the integration of the material with the body. Many workers have introduced the concept of combining synthetic polymers with natural polymers to enhance biocompatibility.
In this study poly(ε-caprolactone) (PCL) was chosen and the natural polymer fibronectin was immobilised onto this surface. In a further attempt to stabilise and facilitate compatibility of the cell-biomaterial interface, the enzyme tissue transglutaminase (tTG) was also immobilised onto the fibronectin coated PCL surface. This enzyme catalyses the post-translational modification of proteins by forming inter and intramolecular ε(γ-glutamyl) lysine cross-links in inter- and intracellular proteins. The bonds that form are stable, covalent and resistant to chemical, enzymatic and physical disruption. The cross-linking of extracellular proteins is thought to enhance cellular responses such as cell attachment, spreading and differentiation at the biomaterial interface. However tTg may act as a receptor adhesive protein without protein crosslinking via its interaction with the B 1 and B 3 integrins (See Gaudry et al., 1999, Exp. Cell. Res. 252, 104-113; Akimov et al., 2000, J. Cell. Biol. 148, 825-838).
Jurgensen et al., (1997) showed that tTG could be a new biological ‘glue’ for cartilage-cartilage interfaces. Tissue TG has 62% greater adhesive strength than that of Tissucol, a commercially available fibrin-glue preparation Jones et al., (1997) showed that human endothelial cells transfected with anti-sense tTG, showed a decrease in cell adhesion and spreading. The theory of tTG being involved in cell attachment is also supported by the findings of Gentile et al., (1992) using Balb-c 3T3 fibroblasts, Borge et al., (1996) using chondrocytes and Verderio et al., (1998) using Swiss 3T3 Fibroblasts.
In the present study, three different methods were used to try and immobilise fibronectin and tTG. All methods were based on the theory that tTG would bind to the immobilised fibronectin on the PCL, because fibronectin has a tTG binding site (Jeong et al., 1995). This binding has been shown to be linked with the first 7 residues at the N terminal domain of tTG. However, reduction and alkylation of fibronectin, destroys its ability to associate with the tTG, suggesting that some features of its tertiary structure are necessary for the binding of the enzyme.
The tTG was immobilised onto the fibronectin coated PCL surface in either 0.1 M or 5 mM EDTA to prevent tTG cross-linking occurring before the biotin-cadaverine experiment was performed. It was hoped that this would not affect the binding properties of the enzyme. Jeong et al., (1995) showed that binding occurs in the absence of Ca 2+ and that the alteration in the conformation of the enzyme is not essential for the formation of the fibronectin-tTG complex.
The three methods of immobilising tTG to PCL were, a) adding fibronectin and tTG in solution overnight at 4° C., b) immobilising fibronectin onto the surface by evaporation and then immobilising tTG onto the surface by evaporation, c) immobilising fibronectin onto the surface by evaporation and then adding tTG and leaving it for 1 h at room temperature.
The ELISA techniques demonstrated the presence of fibronectin on PCL when immobilised by evaporation and also demonstrated the presence of tTG on fibronectin coated PCL when immobilised by either evaporation overnight or by incubation for 1 h at room temperature.
The activity of tTG on the PCL surface was evaluated using the biotin-cadaverine incorporation assay. It was found that tTG was not active on the surface of PCL when immobilised in solution together with fibronectin. An explanation for this would be that fibronectin is inaccessible for tTG cross-linking due to its unfavourable configuration or alternatively, the fibronectin did not bind to the PCL at 4° C. It was also found that tTG was not active on the fibronectin coated PCL surface when the tTG was immobilised by the evaporation method. An explanation for this would be that the evaporation method renders the tTG inactive as it was shown that under these circumstances tTG is present on the PCL surface (as demonstrated by the ELISA technique). When the tTG was immobilised by incubation for 1 h at room temperature however, it was found to be active on the surface.
Tissue transglutaminase is regulated by calcium and nucleotides (Smethurst and Griffin, 1996). They found that tTG was active at 100 μM calcium and when ATP or GTP were absent or in very low concentrations. In the cytoplasm of a resting energy-rich cell, the ATP levels may be as high as 8-11 mM and GTP levels between 50 and 300 μM, with a proportion of each being bound to cytosolic proteins, giving lower free nucleotide concentrations. In the resting state the free calcium is around 100-200 μM. Under these conditions their data suggest that tTG activity in the cytosol would be switched off. However, in DMEM (the medium that human osteoblast cells are cultured in) or in the in vivo situation there is >100 μM calcium, which is enough to activate the tTG on the biomaterial surface.
When the human osteoblast cells were seeded onto the fibronectin/tTG coated PCL surface, tTG had a profound effect on cell morphology (as viewed using E.S.E.M.). The results clearly demonstrated that cell spreading in serum free medium occurred 30 minutes after cell seeding unlike the cells on the PCL surface which remained rounded and unlike the cells on the PCL+fibronectin surface which had only just started to spread. The cells on the fibronectin/tTG coated surface spread quicker than cells seeded on tissue culture plastic in 10% serum containing medium (positive control).
After 1 hour incubation on the different surfaces, similar results were obtained and 3 hours after cell seeding the human osteoblast cells had formed a monolayer on PCL+fibronectin, PCL+fibronectin+tTG and on tissue culture plastic. The cells on PCL however, were still rounded in morphology and only a few cells were present indicating that some cells had probably detached during the hour.
It can therefore be concluded from the E.S.E.M. results, that human osteoblast cells immediately respond to the tTG on the PCL surface, which subsequently causes earlier cell spreading. This surface is far more preferential to PCL alone, PCL coated with just fibronectin and tissue culture plastic.
Cells initially attach to the biomaterial by physicochemical factors, i.e. charge, surface free energy or the water content of the biomaterial (Schamberger and Gardella, 1994) and then strongly adhere to ECM proteins, which have been deposited on the biomaterial surface. It is thought that initially the cells attach to the fibronectin coated PCL surface. Evidence then suggests that tTG cross-links the fibronectin with other cell surface bound proteins forming a stabilised extracellular matrix on the biomaterial face. Cross-linking of the surface bound proteins may also trigger the activation of integrins. The cell may also utilise the tTG as an adhesion protein in association with the β1 integrin in order for it to attach to the biomaterial surface. Gaudry et al., (1999) has shown that tTG co-localises with the β1 integrin and Akimov et al., 2000, J. Cell. Biol. 148, 825-8 has suggested that tTg may mediate the interaction between the B1 and B3 integrins and fibronectin.
The differentiation of human osteoblast cells on the tTG coated PCL surface was investigated. It was necessary to first establish the lowest amount of serum required in DMEM that will allow osteoblast proliferation. The results showed that cells can proliferate in as little as 2% serum containi medium on tissue culture plastic, however they require a minimum of 10% serum containing medium when cultured on PCL. The rate of proliferation is also slower on PCL than on tissue culture plastic.
The differentiation of cells on the TCP. PCL, PCL+FN and PCL+FN+tTG surfaces was measured 2 days after cell seeding using the alkaline phosphatase activity assay and was expressed as per μg DNA. The preliminary results indicate that tTG, does not have any detrimental effect on the alkaline phosphatase activity/differentiation of HOB cells on PCL when compared to PCL coated with fibronectin. However, this needs to be investigated at later time points. Kaartinen et al., (1999), however believes that the cross-linking of osteopontin (a major noncollagenous bone protein) by tTG increases its collagen binding properties. This leads us to believe that tTG may be a promoter of cell differentiation because it not only cross-links extracellular proteins but also helps in ECM molecule recruitment.
Poly(ε-caprolactone) coated with fibronectin and tissue transglutaminase is a bioactive biomaterial that enhances cell attachment, spreading and stabilises the extracellular matrix on the biomaterial surface making the human osteoblast-biomaterial interface stable. This biomaterial has potential applications in bone grafting where cells need to rapidly colonise the biomaterial in order to produce new bone. The PCL could also be re-enforced to give it the mechanical strength required for hip and knee prosthesis.
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The present invention provides a medical implant material comprising mammalian transglutaminase and a polymer, wherein the transglutaminase is provided in the absence of free divalent metal ions and wherein the polymer is associated with the transglutaminase binding protein. Preferably, the transglutaminase is a tissue transglutaminase, which is coated on, impregnated into or covalently linked to the polymer. The polymer may be naturally occuring or synthetic, and may be biodegradable or non-biodegradable. The medical implant material may further comprise a reinforcing agent and/or one or more additional polymers. The invention further provides the use of a mammalian transglutaminase in a method for improving the biocompatibility of a medical implant material, the method comprising the steps of (i) providing a medical implant material comprising a polymer associated with a binding protein for binding the transglutaminase, and (ii) treating said material with a mammalian transglutaminase.
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This is a divisional application of Ser. No. 727,681, filed Apr. 26, 1985.
BACKGROUND OF THE INVENTION
This invention relates to product cooling and more specifically to a method, system and apparatus for rapidly cooling fresh meat, pork, sheep products or the like to retard bacterial growth thereon while simultaneously minimizing dehydration thereof.
It has long been a problem in the art of processing meat, and the like to simultaneously cool such products at a rate sufficient to prevent the growth of bacteria and at the same time maintain the moisture content of the product at a high level. A high moisture content in such products not only adds greatly to the taste and appearance of such products but the overall weight of the product is greater resulting in a higher price realized when the product is sold by the pound. High moisture content must be achieved without any water contacting the product which would result in its condemnation by inspectors of the United States Department of Agriculture (USDA).
Typically, the carcass of the warm, freshly slaughtered animal is placed or hung in an enclosed room or holding chamber through which refrigerated air is circulated to thereby reduce as rapidly as possible the temperature of the carcass from approximately 100 degrees F. down to approximately 40 degrees F. to stop bacterial growth thereon. Prior art cooling systems are able to achieve this 60 degree F. temperature drop by slowly circulating cool air through the chamber containing the product and through a cooling unit such as a plate fin-type evaporator connected to a conventional refrigeration system. The air would have a relative humidity of approximately 60 percent. The temperature of this slow moving relatively dry air would increase 3 or 4 degrees F. as a result of the heat given off by the product. This 3 or 4 degrees F. temperature rise would then cause the air to have an affinity for moisture which it would take out of the product causing the product to shrink from dehydration. Air having such a 60 percent relative humidity slowly circulated over the product in prior art systems would typically result in shrinkage of the product from dehydration of approximately 0.75 percent if the product was beef and 1.5 percent if the product was pork.
In such prior art systems the air passing through the cooling unit was typically cooled to approximately 28 degrees F. and then circulated over the product where it picked 3 to 4 degrees F. and was then returned to the cooling unit with a temperature of approximately 32 degrees F. The air was passed through the cooling unit at approximately 500 feet per minute and the water was removed therefrom while keeping the relative humidity at approximately 60 percent as aforementioned. To reduce the temperature of the air in the plate fin-type evaporator this 3 or 4 degrees F. prior to its discharge back into the chamber required the refrigerant passing through the evaporator to be low or approximately 13 degrees F. and required approximately 1.2 horsepower per ton to thus cool the air. A higher velocity of air through the plate fin-type evaporator of the prior art was not achievable without an excessive amount of free water being entrained therein which would then settle on the product resulting in its condemnation as aforementioned.
Applicant discovered that if the velocity of the air being circulated over the product and through the cooling unit is very high, the air would pick up less heat, for example, only 1.5 to 2.0 degrees F., from heat given off by the product before the air is returned to the cooling unit. This low temperature increase is insufficient to cause the air to crave moisture thus less moisture is taken out of the product. In addition because of this low increase air temperature, the cooling unit requires less energy consumption to remove this heat from the air prior to its recirculation back to the chamber holding the product. Thus, the refrigerant passing through the evaporator cooling coils of the cooling unit can be at a higher temperature than that of the prior art, for example, approximately 28 degrees F. At this 28 degrees F. refrigerant temperature, the cooling coils of the evaporator run "wet", thus less moisture is removed from the air passing over them and applicant is able to maintain the relative humidity of the air circulating over the product at between 90 and 100 percent which further reduces absorption of moisuture from the product. Applicant's novel air diffuser design adjacent the cooling coils of the cooling unit insures that all free, entrained water is removed from the moisture ladened air so as not to fall on the surface of the product. Operation of applicant's system has resulted in dehydration or shrinkage of only 0.25 percent if the product were freshly slaughtered beef and 0.50 percent if the product were pork. As can readily be seen, this is only one-third of the shrinkage of the product experienced by the prior art methods.
This energy savings and reduction in the shrinkage of the product is achieved by applicant's use of a spiral wrap fin-type evaporator or cooling means in the refrigeration system which includes the air diffuser of applicant's novel design. The cooling system will be described in detail later. It is sufficient to say at this point, however, that applicant's diffuser design permits air to be forced past or over the cooling coils in the evaporator at a face velocity of between 800 and 1,000 feet per minute and exit with a very low free, entrained water content but with a relative humidity of between 90 and 100 percent as aforestated. Because the cooling coils of the evaporator are run "wet", that is, passing refrigerant through them having a temperature of approximately 28 degrees F., only 0.9 horsepower per ton to cool the air is required or a 0.3 horsepower per ton savings over the prior art systems. The air thus rapidly recirculated by applicant's system is only heated a maximum of 2 degrees F. before being returned to the evaporator for recooling contrasted with a prior art difference of 4 degrees F. as aforementioned.
Thus, applicant's novel cooling system to be hereinafter described in detail not only results in less weight loss or shrinkage due to dehydration of the product, it achieves this result consuming less power than the prior art cooling systems.
It is therefore the primary object of the present invention to provide a superior method and apparatus for minimizing dehydration of freshly slaughtered meat products and the like and do it with less electrical power consumption.
It is another object of the present invention to provide a method and apparatus for accomplishing the stated purpose which maintains a high degree of relative humidity in the cooled air but a low entrained or free water content.
It is yet another object of the present invention to provide a method and apparatus for accomplishing the stated purpose which has a cooling means that is capable of moving air through it at a very high face velocity and recirculating it rapidly over the meat product resulting in less heat and thus less moisture being given up by the product.
It is a further object of the present invention to provide an extremely efficient air cooling means having a novel air diffusing device incorporated therein.
These and other objects and purposes of this invention will be understood by those acquainted with the design and construction of such methods and apparatus upon reading of the following specification and accompanying drawings.
In the drawings:
FIG. 1 is a digrammatic illustration of the refrigeration system and cooling apparatus of the present invention;
FIG. 2 is a cross-sectional view of the cooling apparatus and diffuser taken along the lines 2--2 of FIG. 1 with the cooling coil shown schematically except where the cooling coil fins are illustrated;
FIG. 3 is a cross-sectional view taken along the lines 3--3 of FIG. 2; and
FIG. 4 is an enlargement of the structure encircled in FIG. 3.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Referring now to the drawings where like characters of reference depict like elements in each of the several figures, numeral 10 in FIG. 1 denotes generally the cooling system of the present invention for rapidly cooling products such as freshly slaughtered beef, pork, sheep or the like while simultaneously minimizing their dehydration. The cooling system 10 includes a controlled environment chamber or holding room 12 in which the product, for example, several freshly slaughtered beef carcasses 14 are hung to be cooled.
A refrigerant evaporator 16 is located adjacent the ceiling of the holding room 12 above the product 14 to provide forced circulation of cooled air 18 out of the evaporator 16 (see arrows) down over and around the product 14 and back to the evaporator 16. Liquid refrigerant is supplied from a condenser 20 to the evaporator 16 through liquid pipe line 22. A conventional thermostatic expansion valve 24 having a thermostat bulb 26 is also provided in contact with the suction line 28 for controlling the temperature of the system. The suction pipe line 28 is, in turn, connected to a refrigerant compressor 30 which compresses the refrigerant gas and delivers it to the condenser 20 to complete the cycle in a well known manner.
Referring now to FIGS. 2-4, the evaporator 16 or the present invention is shown as having a core 32 comprising a plurality of cooling coils or rows of tubes 34 each row having three spirally wound loops. The loops of each row are serially connected so as to provide a single tube passage through the core. The tubes 34 are supplied with a multiplicity of closely spaced fins 36 located on the tubes thus enabling heat to be transferred by the core more efficiently. Rectangular shaped brackets 38 are provided at spaced-apart locations around the outside of the core 32 to keep the tubes 34 in one row in vertical alignment with the tubes 34 in an adjacent row. Spacers 40 are also provided beneath each row of tubes 34 to support the tubes. The spacers 40 are connected at their ends to the interior sides of the brackets 38. Upper and lower circular flanges 42,44, respectively, L-shaped in cross-section are provided adjacent the top 46 and bottom 48 of the core 32 as viewed in FIG. 3. The flanges 42,44 are secured to the brackets 28 and serve to define, together with the inner-most tubes 34 of each row, a cylindrical-shaped, open, interior area 50.
An air diffuser 52 is provided adjacent the inner-most tubes 34 of each row. The air diffuser 52 consists of a plurality of vertically extending, parallel, spaced-apart baffle plates 54 which extend between and are secured at their ends to the upper and lower circular flanges 42,44. The baffle plates 54 all extend in the same relative direction around the circular flanges 42,44 as can best be seen by referring to FIG. 2. Each baffle plate 54 has a longitudinally extending lip or flange portion 56 on the edge thereof furthest from the inner-most tubes 34 of each row for penetrating water on the baffle plates 54 from being blown into the open air 50. The baffle plates 54 serve the dual function of first aligning the air passing between the plates into substantially parallel streams which are then drawn downward through the lower flange 44 by a fan as will be more fully described later. Secondly, the baffle plates 54, due to their overlapping arrangement, provide a surface for any free water entrained in the air to impinge thus separating the water out of the air. This free entrained water is primarily condensation which forms on the tubes 34 and fins 36 and is blown therefrom by the rapidly moving air being drawn over the tubes and fins toward the baffle plates 54.
A circular condensate collecting pan 58 is provided beneath the core 32 for receiving the aforementioned condensate 59 and draining it away in a pipe 60. A plurality of spaced-apart brackets 62 are secured to the outside of brackets 38, as can best be seen in FIG. 4, which serve to support the outer wall 64 of the pan 58. The inner wall 66 of the pan 58 is secured to the lower circular flange 44. The pan 58 also has a layer of insulation 68 adjacent the bottom thereof for preventing condensation from forming on the outside surface of the bottom and dripping therefrom. A vertically extending wall 70 is secured to the lower circular flange 44 to insure that water running down from the baffle plates flows over the upper surface of the lower circular flange 44 and into the pan 58 and not into open area 50. A hood or cover 72 is positioned on the top 46 of the core 32 and encloses the upper opening of the interior 50.
A fan 74 having a plurality of blades 76 is driven by an electric motor 78 which in turn is mounted by support arms 80, in the interior area 50 of the core 32. The fan 74 serves to draw air from outside of the core 32, see arrows in FIG. 4, over the tubes 34 and fins 36 toward the baffle plates 54 of the air diffuser 52. Any water or condensate blown off of the tubes 34 or fins 36 is entrained in the air and is drawn into engagement with the baffle plates 54 where it adheres and is forced toward lips 56 from which it flows down into pan 58 as aforedescribed. The air, however, tends to curve around the lips 56 of the baffle plates 54 and through the gaps 82 between the baffle plates 54. The water being heavier does not bend and thus is propelled onto the sides of the baffle plates 54. As the air enters the interior 50, it is rotating clockwise, as viewed in FIG. 2, and is then bent downward and is drawn by the fan 74 as a mass substantially normal to the plane of the fan blades 76. Applicant discovered that rotating the fan blades 76 in a direction opposite to the direction in which the baffle plates 54 extend toward the interior 50 or counterclockwise as viewed in FIG. 2 that the blades 76 are better able to "bite" the downward body of air thus greatly improving the efficiency of the fan 74. In effect, the air diffuser 52 acts as an "air straightener" or "air aligner" which forces all of the air exiting the gaps 82 to rotate in the same direction. By then rotating the fan blades 76 in a direction opposite thereto, approximately one-third of the loss in air flow resulting from the pressure drop across the diffuser 52 can be recovered. The speed of fan 74 and blade pitch is chosen to cause the velocity of the air passing over the surface of the tubes 34 and fins 36 to be between 800 and 1,000 feet per minute.
A hollow, cylindrical-shaped extension member 84, shown in phantom lines in FIG. 3, may be added beneath the pan 58. The fan 74 is positioned in the extension member 84 adjacent the lower open end thereof. This modification would insure more complete alignment of the air from the gaps 82 prior to the airs engagement with the fan blades 76 as well as to discharge the cooled air closer to the product.
Applicant's method of system operation has as its object, as aforementioned, the rapid cooling of carcasses of meat products to retard bacterial growth thereon while simultaneously reducing dehydration of the product to levels substantially below those realized by prior art methods.
Typically, meat in the form of beef, pork, or sheep carcasses 14 is hung overnight after daily slaughter operations in a large, precooled, controlled environment chamber containing a plurality of zones or groups each containing twenty or so carcases. After a retention time of between 14-24 hours, and with cooled air from a cooling unit continuously recirculated over the carcasses at a temperature of approximately 32 degrees F., the carcasses themselves achieve a temperature of approximately 40 degrees F. The next day, zones of carcasses are removed from the chamber for shipment, slaughter operations are resumed, and freshly slaughtered meat having a temperature of between 100-102 degrees F. is brought into the chamber to refill the vacated zones.
Air 18 from the cooling unit 16 is delivered to the chamber 12 and rapidly circulates around the meat. The temperature of the air leaving the chamber 12 is maintained between 30-50 degrees F. and preferably between 32-48 degrees F. The air 18 entering the chamber 12 has a relative humidity of no less than 90 percent and with no visible free water present therein. The air 18 is circulated or drawn over the meat by fan 74 sufficiently rapidly so that the temperature of the air only rises between 1.5 and 2 degrees F. from heat given off by the meat before it is returned to the cooling unit 16. As a result of the high humidity of this air and the fact that the temperature of the air is only able to rise between 1.5 to 2 degrees F. due to its rapid circulation over the meat rather than the 3 to 4 degrees F. of the prior art, the air has hardly any affinity for moisture and thus shrinkage of the meat is less than one-third of that realized in systems of the prior art.
The heated air 18 is then drawn back into the cooling unit and is passed over the cooling coils 32 contained therein at a velocity of no less than 800 feet per minute and preferably between 800 and 1000 feet per minute by the fan 74. The refrigerant circulated through the cooling coils 32 from the compressor 30 and condensor 20 of the cooling unit 16 is set high or approximately 28 degrees F. so that the coils run "wet", i.e., less moisture can be taken out of or is removed from the air by the coils than if the refrigerant temperature were run low as is the case in the prior art systems. The temperature drop across the cooling unit 16 from the inlet to the outlet is held at 2 degrees F. or less by controlling the refrigerant temperature. Thus, the temperature of the air leaving the cooling unit 16 and entering the chamber 12 is maintained 2 degrees F. less than the aforementioned temperature of the air leaving the chamber 12 and entering the cooling unit 16.
The cooled air, after it is drawn over the cooling coils 32, enters the diffuser 52 wherein all free, entrained water is removed from the air so as not to settle on the meat which would lead to its condemnation. Free water is defined here to mean water in the air that is visible to the naked eye.
The thus cooled air is then returned to the chamber 12 having the aforesaid high relative humidity and the process continually repeats itself. Because these refrigeration systems are usually in continuous operation, the monetary saving in electrical costs utilizing applicant's system is substantial. Additional monetary gain is achieved utilizing applicant's novel method, system and apparatus in addition to the aforementioned energy savings due to the increased sale price of the product obtainable that results from its increased weight due to one-third less shrinkage from dehydration than the prior art systems.
Various changes and modifications may be made to the method, system and apparatus of the present invention as will be readily apparent to those skilled in the art. Such modifications and changes are within the scope and teaching of this invention as defined by the claims appended hereto.
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A method, system and apparatus is disclosed for rapidly cooling and simultaneously maintaining a high moisture content in freshly slaughtered meat products and the like placed in a chamber through which preconditioned air is circulated. This is achieved by limiting the air temperature rise by utilizing air flow rates past the product at a level such as to cause the air to increase in temperature from entry into the chamber to exit from the chamber by no more than approximately two degrees F. and by providing a cooling apparatus which reduces the temperature of the air while removing free water from it yet is capable of maintaining the relative humidity of the air at no less than ninety percent.
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This is a division of U.S. Application Ser. No. 788,394, filed Oct. 17, 1985, now U.S. Pat. No. 4,773,003.
BACKGROUND OF THE INVENTION
The present invention relates to a monitor and analyzer for digital communications channel activity, and more particularly to a monitor and analyzer for passive interconnection to a computer data channel or the like, for providing a visualization for operator analysis of data channel activity.
In the field of hardware and software diagnostic evaluation of computer signals it has been necessary to develop hardware systems and methods of analysis which are based on less than totally comprehensive system operating parameters. It is technically impractical, if not impossible, to fully monitor and analyze all signal state changes which occur in any realistically sized computer system at the real-time rates of change which such signals undergo. The sheer quantity of possible signals which exist within and without a computer system limits the practicality of designing and operating a total system monitor, for in this case the complexity of the monitor exceeds that of the computer being monitored. Selective monitoring of particular computer circuits represents a feasible design problem, particularly where the circuits selected for monitoring are conveying data signals of particular interest, and which are particularly useful in measuring successful operation of the system. For this reason, signal lines associated with computer data channels may preferably be selected as monitor points, for these signal lines are generally associated with the useful data which the computer is either processing or transmitting during any given operation.
Monitoring signal lines representative of computer data channel activity presents further problems, however, for data transmission rates over these lines often occur at millions of transitions per second. Therefore, a hardware or software monitoring system must be capable of responding to signal changes at these high data transmission rates, and if the data is to be collected for useful analysis such systems must be capable of storing the information as it is transmitted at these rates. This leads to the further problem of providing sufficient storage for receiving and accumulating large quantities of data, at rates of speed which coincide with the data transmission rates over the data channels. This problem is technically impractical or impossible of solution if more than a few seconds of computer data channel activity is to be collected, for the volume of storage which must be made available for such collection becomes extremely large if any significant data accumulation is desired. Further, even if a sufficient storage volume is provided for collecting significant amounts of data from a computer data channel, the amount of time required for analysis of such data is invariably longer than the time required to transmit the data. Therefore, analysis of bulk quantities of data is usually accomplished offline, at nonreal-time rates, frequently in a post-processing computer which is configured exclusively for analysis of such volumes of data.
If real-time monitoring and analysis is desired it is usually required that sampling techniques be employed, wherein random or preselected samples of data are captured from a data channel and are analyzed in real time, utilizing an analysis scheme which has some statistical validity for predicting the existence or nonexistence of particular events being monitored. Such sampling techniques can be triggered by predetermined signal events within a computer, as for example by initiating a sampling interval at the time a data output channel is activated, and continuing the sampling interval until such time as the data output channel is deactivated. The statistical samples so collected are presumed to be representative of the actual real-time data channel activity, and diagnostic and other assumptions are made from observations made of the data so collected. Data monitoring and analysis can also be predicated by an event trigger which causes a brief period of collection to occur wherein all data channel activity is retrieved and stored for a brief time interval after the event of significance has been detected. Such a technique might be utilized wherein a fault indication signal line is monitored, and the occurrence of a signal on this line causes a plurality of data channel lines to become monitored, and the signals thereon collected and stored, and an analysis of the data so collected be undertaken in order to attempt to ascertain the cause of the fault indication. It is possible to utilize this technique in real-time conditions if the volume of data collected is sufficiently small so as to permit the analysis circuits to complete their operation before further and additional data is transmitted requiring the same analysis.
Even the last above-described technique is not useful when the cause of the fault detection signal is derived from conditions which occurred on the data channel prior to the occurrence of the fault signal. In this case, it is of no help to collect quantities of data after the fault signal for the condition which led to the fault signal has already passed and the contents of the data channel which might suggest the cause of the fault have not been recorded.
There is a need for a data channel analyzer, and a method for analysis of data transmitted over data channels which provides for the monitoring of data channel activity and for the detection of preselected signal conditions requiring analysis, and for the accumulation of a predetermined volume of channel data occurring before and after the preselected conditions for inclusion in the analysis activity. Further, there is a need for a monitoring system and technique which permits the real-time monitoring and analysis of the data transmitted over a data channel. Finally, there is a need for a system of data channel monitoring and analysis which provides an intelligible display and summary of the results of the monitoring and analysis for convenient and understandable presentation to an operator.
SUMMARY OF THE INVENTION
A method and apparatus for passively monitoring the data channel signal lines of a computer system and the like, including logic circuits for recognizing predetermined events of interest, and collecting and storing a predetermined volume of past and subsequent data in time relationship to the detected event of interest, and circuits for examining the collected quantity of data and for labeling the collected sample with predetermined identifiers and displaying the identifiers in association with intelligible values representative of the data, including the event which caused the data sample to be taken, thereby to enable an operator to visualize the activity of a computer channel according to the protocol defined for the channel activity.
It is a principal object of the present invention to provide an apparatus for enabling operator visualization of computer data channel activity, particularly with reference to predetermined events occurring on the data channel.
It is a further object of the present invention to provide an apparatus for passively monitoring the signal activity on a data channel, and for analyzing the signal activity to detect signal events of predetermined interest, and for recording data transmissions occurring prior to and subsequent to the event of interest.
It is another object of the present invention to provide an apparatus for monitoring data channel activity, and for analyzing such activity according to a predetermined analysis technique, and for presenting a summary display for operator visualization of the results of such monitoring and analysis.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing objects and advantages will become apparent from the following specification and claims, and with reference to the appended drawings, in which:
FIG. 1 shows a functional block diagram of the invention;
FIG. 2A shows a schematic logic diagram of the channel interface circuits;
FIG. 2B shows a logic diagram of control circuits associated with the channel interface;
FIG. 2C shows a logic diagram of the sampling enable control circuits associated with the channel interface;
FIG. 3 shows a functional block diagram of the cache memory and control;
FIG. 4 shows a functional block diagram of the FIFO and control;
FIG. 5 shows a functional block diagram of the system controller;
FIG. 6 shows a diagram of a typical data channel word; and
FIG. 7 shows a preferred form of visualization of the results of a monitoring operation.
FIG. 8 shows the steps of the method of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring first to FIG. 1 there is shown a functional block diagram of the invention; illustrating the various paths where parallel data transmission occurs, but showing none of the associated control signal lines. A channel interface 10 is designed to receive input signals from a computer data channel or similar data bus of the type having a plurality of information bits transmitted over parallel lines. Channel interface 10 is connected to the individual signal lines via a plurality of input lines 12, which are connected to the data channel lines associated with signals which it is desirable to monitor. The total number of these signal lines may vary, but one form of the preferred embodiment is capable of monitoring thirty-five individual channel lines. Channel interface 10 also has a secondary set of input lines 14 which are adapted for connections similar to input lines 12. Input lines 14 are adapted to receive user selectable input signals, which signals may be derived from signal points of interest in the equipment being monitored. The preferred embodiment utilizes ten user selectable lines 14, and lines 14 may optionally be configured for connection to other channel signals or to other signals within any particular piece of equipment of interest. For example, one of the user selectable lines 14 may be connected to a clock signal associated with the equipment being monitored, or to a real time clock signal. Channel interface 10 also includes a set of data bus input lines from data bus 27. These input lines originate in system controller 30, and typically may be an 8-bit or 16-bit data bus of the type commonly used with computer equipment. The information received by channel interface 10 via these data bus lines generally originates within computer 20, is transmitted over computer bus 21 to system controller 30, and is further transmitted over data bus 27 to channel interface 10. The information present on these data bus lines frequently originates as a command entered by the operator through the operator keyboard 22, as will hereinafter be more fully described.
Signal lines which are monitored by channel interface 10 may be selectively transferred into a cache memory 16 via a data bus 15. Cache memory 16 is a high-speed memory which is capable of receiving and storing data samples at high data rates. In the preferred embodiment cache memory 16 is designed to have a capacity of at least 1,000 45-bit words, although the cache memory 16 may be readily expanded either in terms of the number of bits which it is capable of storing or in terms of the number of words which it is capable of storing. Cache memory 16 can receive and store samples at a maximum rate of approximately 12 megahertz (Mz).
Cache memory 16 is connected to a first in, first out (FIFO) memory and control 24 via a data bus 23. FIFO 24 receives data samples from cache memory 16, and contains circuitry for making a determination whether the data samples are to be retained or discarded. If the determination is made that the data samples are to be discarded, FIFO 24 merely clears its internal data registers where the samples are stored. If it is determined that the data samples are to be retained FIFO 24 transfers the data samples to a large store memory 28 via the data bus 27. In the preferred embodiment FIFO 24 is designed to have a data handling rate of at least 5 megahertz, and is capable of transferring data to the large store memory 28 at data storage rates in the range of 2-3 megahertz.
Large store memory 28 is controlled by a system controller 30, which controls and initiates the read/write memory cycles necessary to operate large store memory 28. System controller 30 is in turn controlled either by circuitry within FIFO 24 or by circuitry within computer 20, depending upon whether the system is operating in a data sampling mode or in a data display mode. Large store memory 28 may be designed with a memory capacity in the range of 32K-512K words of 48 bits each. The data stored in this memory is available to computer 20 via system controller 30, or optionally may be transferred via data bus 27 to a high-speed tape storage unit (not shown).
Computer 20 is utilized to maintain command and control of the entire system via computer bus 21 and other input and output control signal lines associated with computer 20. Computer 20 may be a commercially available computer type such as a Model MC85 Single Board Computer, available from Comark Corporation, Medfield, Mass., which has been adapted for use in connection with the invention. Since computer 20 is a general purpose computer system, it is capable of internal storage of operating programs, and interconnection to any of a wide variety of commercially available devices conventionally adapted for such connection. For example, computer 20 is associated with a standard commercially available keyboard 22 and a commercially available printer 32. A commercially available cathode ray tube (CRT) display 36 may also be connected to computer 20 in a manner which is well known in the art. Computer 20 has a standard RS232 external interface connection which is adaptable and compatible with many commercially available devices. It is contemplated that computer 20 may be connected via this RS232 connection to standard telecommunications modems or other similar devices, to permit command and control of the invention to be transferred to a remote location via the telecommunications network.
The invention operates as an independent data logger, which is driven by transitional clocking, i.e., the change of state of signals which are either negative-going signals or positive-going signals, wherein such signals are connected to channel interface 10. The operation and handling of such signals is under the control of preset conditions which are initially entered into computer 20 by an operator, which will be more fully explained hereinafter. Once the preset conditions have been entered the logging and monitoring functions of the invention continue uninterrupted until the preset conditions determine the cessation of sampling and logging. The preset conditions may permit sampling operations to continue uninterrupted for extended periods of time, extending even to several weeks of operation. Obviously, the amount of data collected over an extended period of time may be far beyond the storage capacity of large store memory 28, and in such event the system is designed to store newly acquired data over old data contained in large store memory 28 after it has become completely filled.
For operator convenience computer 20 has an internal operating program which is designed to present to the operator a menu-driven sequence of selection choices. This enables the operator to fashion a monitor or test run which yields great flexibility in specifying the conditions for monitoring and stopping the system. For example, the operator may elect not to sample all activity on the monitored channel, but to sample merely those channel activities which relate to predetermined equipment of interest. By limiting the sampling to only certain equipment of interest activities, it is apparent that the large store memory 28 may collect and store a considerable volume of data related to this equipment. Of course, through the use of high-speed tape storage equipment the operator may choose to acquire and retain data from numerous monitoring runs, resulting in extremely large volumes of data for later analysis.
CHANNEL INTERFACE
Channel interface 10 provides the interconnecting lines for attachment to other computer input and output channels, including signal lines which may be attached to other computer signal generating points of interest. The channel interface input lines into channel interface 10 may be directly coupled to cables and other connectors of remote equipment, a feature of the invention being that it presents a passive electrical interface which does not interfere with the regular data transmission capabilities of the equipment being monitored.
Referring next to FIG. 2A, there is shown a schematic logic diagram of a single signal interface circuit. A plurality of such circuits may be found within channel interface 10, the circuit illustrated being representative of all such circuits. The circuit of FIG. 2A is connected to an input line 12a, which is one of the input signal lines associated with a group of input lines 12. In the preferred embodiment thirty-four such lines are contemplated, although a greater or lesser number may readily be selected. The interface circuit also has an output signal line 15a associated therewith, line 15a being one of a plurality of lines associated with data bus 15. When the signal on line 12a is at a steady state voltage level the output signal on line 15a is at a constant level, which will herein be defined as "low". For purposes of clarity, signals will be referred to as being either "high" or "low", to indicate the relative logic levels of the signal voltage states. It is to be understood that this reference is for purposes of understanding the invention, and any of a wide variety of circuits capable of operating under various voltage operating conditions are possible for use with the invention.
When the input signal on line 12a changes state in either direction a positive pulse appears on output line 15a if the enable latch flip-flop 210 is in the "set" condition. The "set" output of latch flip-flop 210 is connected via line 211 to AND gate 212. When the input signal on line 12a is a steady state low value the output of BUF circuit 216 is high, which is coupled to an input of OR circuit 213. This causes the output of OR circuit 213 to be high, and the output of NAND circuit 214 is also high. These signals are fed as inputs to NAND circuit 215, which therefore has a low output signal. This signal is connected to AND gate 212, resulting in a low output signal on line 15a.
BUF circuit 216 is a signal inversion circuit having a relatively slow response time compared to the other circuits in channel interface 10. The steady state output signal from BUF circuit 216 is high, but the second input into NAND gate 214 is low, thereby providing a steady state output signal from NAND gate 214 which is high. When the input signal on line 12a suddenly transitions from low to high the output of NAND gate 214 immediately goes low, and the output signal of NAND gate 215 follows by going high. This output signal is transferred through AND gate 212 to appear at output line 15a as a high signal. A very short time later, corresponding to the response time of BUF circuit 216, the output of BUF circuit 216 goes low, thereby causing the output of NAND gate 214 to again go high. This output signal causes NAND gate 215 to again go low, resulting in the signal on output line 15a going low. In this manner, a signal transition on input line 12a from low to high causes an output signal to briefly appear on line 15a . This operation presumes that latch circuit 210 is in the "set" state, having a high signal on line 211.
A similar result occurs during a signal state change on input line 12a from high to low, for under this condition a brief high signal will also appear on output line 15a. The time duration of the high output signal on line 15a is a function of the switch delay time of BUF circuit 216, which typically is selected to respond in 10-30 nanoseconds. BUF circuit 216 is a commercially available circuit, such as a type SN75127 line receiver available from Texas Instruments, Inc., and all of the circuits shown in FIG. 2A are commercially available logic circuits.
The latch flip-flop 210 is controllable by signals originating in computer 20, some of which are conveyed over computer bus 21 via system controller 30 to data bus 27. Input signal line 27a, which represents one signal line of the data bus 27, is coupled to an AND gate 217. A second signal line 218 is also coupled to AND gate 217, and the signal on line 218 is a computer-generated enable signal which causes latch flip-flop 210 to become set whenever line 27a is high. An input signal on line 219 is also computer generated to cause latch flip-flop 210 to become reset or disabled. Each of the channel interface™circuits in channel interface 10 include the foregoing circuitry, and computer 20 is therefore able to selectively activate various channel data bits for monitoring by first sending a preselected data word over computer bus 21 to system controller 30, which in turn selectively signals lines 27a-27n, followed immediately by a latch enable signal over line 218, which line 218 is connected to all channel interface circuits. Similarly, line 219 is connected to all channel interface circuits so that the respective latch enable flip-flops 210, etc. are simultaneously disabled by the activation of a single computer 20 output signal.
FIG. 2B shows the control circuits for gating the output signals from the channel interface circuits into the cache memory 16. Each of the channel interface output signal lines 15a, 15b, . . . 15n are connected into an OR gate 225. The output of OR gate 225 is connected to an AND gate 226, which AND gate has a further signal input line 230. Signal line 230 receives a "sampling enable" signal, which permits the output of OR gate 225 to set a latch flip-flop 232. Output line 234, which is denoted the "sample ready" signal line, is connected to a control circuit in cache memory 16, to initiate a cache memory data input sequence. At the completion of the data input sequence into cache memory 16 a control signal is transferred from cache memory 16 back to flip-flop 232 via line 236, to disable the "sample ready" signal line.
Referring next to FIG. 2C, there is shown a schematic logic diagram of the sampling enable circuits. These circuits determine the conditions under which the cache memory 16 is activated to accept samples from the channel interface 10, by controlling the input enable signal to AND gate 226 (FIG. 2B) via signal line 230. Signal line 230 goes high whenever sample enable latch 238 becomes set. Signal line 230 goes low whenever sample enable latch becomes reset. Sample enable latch 238 becomes set by a number of signals which may be coupled into OR gate 240, which is designated "start sample" OR gate 240. Sample enable latch 238 becomes reset by a number of signals which are fed into OR gate 242, which is designated "stop sample" OR gate 242. Among the conditions which cause a sampling enable to be generated by signal line 230 are an external start signal over line 258, or a computer start signal over line 247. Additional start conditions (not shown) may also be fed into OR gate 240 to control the setting of sample enable latch 238, and thus cause sample data to be input. Similarly, among the signals which cause deactivation of the sampling enable signal on line 230 are an external stop signal over line 258, or a computer stop signal over line 248. Additional stop conditions (not shown) may also be fed into stop OR gate 242, especially signals from condition check logic 424 in FIFO and control 24 (FIG. 4), to control the reset of sample enable latch 238 and thus cause cessation of sampling. The external start and stop signals are generated by external wiring, i.e., by connecting lines A to appropriate external signal generating events which can control the beginning and end of a sampling interval. The computer start and stop signal lines 247 and 248 are controlled by computer 20, through the data signals transferred over computer bus 21 via system controller 30 and data bus 27. These signals are generated under computer 20 control, usually as a function of operator-entered input data.
The output of AND gate 256 is determined by a 4-bit comparator 252. Comparator 252 receives two groups of four input lines, and output line 253 of comparator 252 goes high whenever a match is made between the respective 4-bit data quantities, which are respectively designated "A" and "B" in FIG. 2C. The 4-bit quantity designated "A" may be derived over signal lines which are externally connected to signal generating sources of interest. The 4-bit quantity designated "B" is generated over signal lines which are derived from computer 20, via computer bus 21, system controller 30 and data bus 27. Computer 20 generates the 4-bit quantity "B", and subsequently generates a latch enable signal over line 254 to cause this 4-bit quantity to become stored in a 4-bit latch register 255. Latch register 255 holds this information in constant comparison with the 4-bit external quantity "A", and whenever a match is found the comparator 252 will generate a signal on line 253. The signal on line 253 passes into AND gate 256, which is also conditioned by an enable signal on line 257. The presence of both these signals causes AND gate 256 to generate an output signal over line 258 which is received by AND gates 259 and 260. AND gate 259 is further conditioned by an external start enable signal over line 245, and the presence of this signal causes start OR gate 240 to set sample enable latch 238 and generate a sampling enable signal over line 230. The signal output on line 258 also appears at AND gate 260, which is also conditioned by an external stop enable signal over line 246, the presence of both causing stop sample OR gate 242 to generate a signal which resets sample enable latch 238 and removes the sampling enable signal at line 230. As described hereinbefore, the sampling enable signal at line 230 provides the signal for causing the cache memory 16 to begin storing data samples transmitted over data bus 15. These data samples are derived from signal state changes detected on the respective input lines 12.
CACHE MEMORY AND CONTROL
Referring next to FIG. 3, there is shown a functional block diagram of cache memory and control 16. Cache memory and control 16 includes a sample register 310 which is connected to data bus 15, to receive and hold data samples transmitted over data bus 15. Sample register 310 is activated by a signal over line 312, from write logic 314. Write logic 314 essentially contains latch circuits for receiving "sample ready" signals over line 234 (FIG. 2B), and for activating a memory storage cycle in memory 316, and for initiating a timing sequence in timing chain 318. Further, write logic 314 functions to determine whether memory 316 is in an active or inactive status, and whether it is able to receive further information over memory bus 311. Finally, write logic 314 generates a "disable" signal over line 236 to complete the transfer sequence of a data sample into sample register 310.
As indicated hereinbefore, cache memory 16 contains a small, high speed memory 316 which is capable of storing at least 1,000 45-bit words before reaching its storage capacity. Of course, it is possible to expand memory 316 beyond this storage limitation, depending upon the particular data monitoring needs. Memory 316 is controlled by a timing sequence which is generated by means of timing chain 318. Timing chain 318 is actuated by write logic 314, by generating a signal over line 315. The various timing signals generated by timing chain 318 are designated (a)-(e), and are typically associated with the read and write cycles of a high-speed memory of a type commercially available, to permit data to be stored or retrieved at approximately a 7-12 megahertz rate. Data samples may therefore be received over memory bus 311 by memory 316 at a maximum rate which is limited by the memory cycle, which in this case is approximately 12 megahertz. Likewise, data samples may be retrieved from memory 316 by output register 320, via memory bus 311, at data transfer rates of approximately 7 megahertz. However, in actual practice, the data transfer rate via output register 320 is limited by the data transfer rate of large store memory 28, which is considerably slower than 12 megahertz.
Write logic 314 receives a "sample ready" signal from channel interface 10 over line 234. Upon receipt of this signal write logic 314 generates a series of more or less simultaneous signals. A signal is generated over line 315 to activate timing chain 318; a signal is generated over line 317 to activate the write buffer 326, and a signal is sent over line 319 to deactivate read buffer 328; a signal is sent over line 321 to activate the cache memory 316; and a signal is sent over line 312 to condition sample register 310 for the receipt of data over data bus 15. A predetermined time later, which is sufficient for the capture of the data into sample register 310, write logic 314 sends a signal over "disable" signal line 236 to reset the latch flip-flop 232 in channel interface 10. The timing chain 318 generates a series of timing pulses (a)-(e) which are utilized to energize the necessary control signals to enable the transfer of data into cache memory 316.
Address control of memory 316 is maintained by write counter 330 during data transfer operations into memory 316. Write counter 330 is an incremental counter which has a total count capacity equal to the number of available addresses in memory 316, and each time a new data word is transferred into memory 316 a signal from timing chain 318 increments write counter 330 by one count. The count value in write counter 330 is transferred to write buffer 326 via lines 327, and write buffer 326 serves as the address register for memory 316 during a write operation.
During a read operation, when data is transferred from memory 316 into output register 320 the control of memory 316 addresses is maintained by read counter 340, which is also an incremental counter having a total count capacity equal to the number of available storage locations in memory 316. Read counter 340 transmits an address value via lines 329 to read buffer 328, and read buffer 328 serves as the address register for memory 316 during read operations, i.e., during operations when data is retrieved from memory 316 and transferred to output register 320. In the event of a timing conflict between a memory read and a memory write operation, the write operation will take priority, because a signal generated by write logic 314 via line 319 will disable read buffer 328 during a write operation, and further a signal from write logic 314 via line 313 causes read logic 338 to abort the read cycle.
Cache memory 16 is designed to receive data from channel interface 10 at random rates and in random burst quantities up to data rates of 12 megahertz. Cache memory 16 is also designed to transmit data to large store memory 28 via FIFO memory and control 24 during periods of inactivity in the write operation at data rates which are limited by the speed of the large store memory 28, which typically operates in the range of 2-3 megahertz. Because of the lack of synchronization between data arriving into cache memory 16 and data being transferred out of cache memory 16, the memory utilizes separate addressing registers for the write and read operations. Write counter 330 increments each time a new data word is loaded into memory 316, and read counter 340 is incremented each time a word is retrieved out of memory 316. Because of the disparity in data transfer rates it is typical that write counter 330 will advance more rapidly than read counter 340, and a mechanism is therefore needed to enable cache memory 16 to track the relative lag in data transfer rates out of memory 316 as opposed to the data transfer rates into memory 316. This is accomplished by compare logic 335. Compare logic 335 receives the count value input from write counter 330, and also receives the count value input from read counter 340. Whenever these counts are unequal compare logic 335 generates a signal on line 336 to enable read logic 338. This signal serves to indicate to read logic 338 that there is currently a continuing need to read data output from memory 316 in order to retrieve all the data that has previously been stored into memory 316. This signal causes read logic 338 to generate an output ready signal over line 322 to FIFO memory and control 24 to initiate the transfer of a further data word from memory 316 via output register 320 to FIFO 24.
There is one condition wherein compare logic 335 may detect a condition of equality between the contents of write counter 330 and read counter 340, wherein the contents of memory 316 have not been fully transferred to FIFO memory and control 24. That is the condition when a significant amount of data has been input into memory 316 without a concurrent output transfer, and write counter 330 has "lapped" read counter 340. This condition may occur, because both counters 330 and 340 are designed to return to zero, or "wrap-around", after their maximum count has been achieved, and in the case of write counter 330 this means that newly arrived data will be overwritten into memory 316 over old data previously stored in the memory. If a significant burst of input data is received without a concurrent output of this data it is possible that write counter 330 may wraparound and actually increment to equal the current count in read counter 340. When a wraparound condition occurs write counter 330 generates a signal over line 331 to set a "wraparound" (w) flip-flop 342. This causes a blocking signal on line 332 which is fed to compare logic 335, and which inhibits compare logic 335 from generating an equality signal even though the contents of the write counter may equal the read counter. Whenever the read counter 340 reaches the maximum count value and wraps around to begin a new count it generates its signal over line 341 to reset wraparound flip-flop 342. This signal removes the blocking signal on line 332 and enables compare logic 335 to generate the necessary equality signal on line 336 whenever the count values are equal. In this manner, cache memory 16 is continuously driven to unload its recently stored contents into output register 320, and to FIFO 24, to the full extent that memory 316 has been filled by the data flowing into sample register 310.
It should be noted that in the case of the write counter "lapping" the read counter, certain data previously stored in memory 316 will become lost to the system, because it will become overwritten by new data into memory 316 before read counter 340 has had a chance to access the old data and transfer it out of memory 316. In this situation, to avoid reading the new data read counter 340 is advanced along with write counter 330. Thus, when one or more write cycles occur under these conditions an equal number of sampled data words will be lost by overwriting and a gap of sampled information will exist between the last data word read from cache memory and the next data word read. In this case a flag is set to indicate to the operator via the display screen 36 that a gap in data retrieval has occurred. This flag will indicate to the operator that apparent inconsistencies in the data displayed are not caused by problems in the system being monitored, but rather by the overflow of data into cache memory 16.
In the preferred embodiment memory 316 has been constructed from the plurality of static random access memory chips organized as 1,024 words by 4-bits. A typical memory chip which is useful for this purpose is manufactured by INTEL, under type designation 2149H-3. This chip provides a memory selection access time of approximately 25 nanoseconds, with suitable data transfer rates for system operation. The timing chain 318 is constructed from a digital delay line circuit, such as a circuit manufactured by ESC Electronics Corporation, Palisades Park, N.J., under Model No. 14TD100. This circuit provides five different timing signals, with a 20 nanosecond delay between each of the five signals. The remaining registers, counters and logic elements which are combined to form cache memory 16 are all commercially available components available from a number of manufacturers.
FIFO AND CONTROL
Referring next to FIG. 4 there is shown a functional block diagram of the FIFO and control logic 24. FIFO and control logic 24 is initially activated by a signal on cache ready signal line 322. This signal is combined in AND gate 410 with a signal on FIFO ready line 411, and a signal on line 413 which activates after a complete timing chain 420 cycle, to activate timing chain generator 420. The signal on line 411 is derived from FIFO register bank 412, and provides an indication that the FIFO registers are in condition to accept new information from cache memory.
Timing chain generator 420 generates a plurality of individual timing signals (a')-(e') which control the relative sequencing of transfers within FIFO and control 24. Timing chain generator 420 is a commercially available semiconductor element, such as one available from ESC Electronics Corporation under model designation 14TD200, which is capable of generating five timing signals at 40 nanosecond intervals. For convenience, each of the timing signals are illustrated in FIG. 4 in sequential order as (a')-(e'), and their respective inputs into the logic circuitry illustrated on FIG. 4 are similarly shown by the same designations.
Timing chain generator 420 generates a first timing signal (a') which is received by input register 416, causing input register 416 to receive the contents of cache memory output register 320, and also generates a signal over line 324 to cache memory read logic 338 to indicate a complete transfer, and thereby to enable another read cycle. The received contents of input register 416 are sensed by address check logic 422 and condition check logic 424 via data channel 421 Address check logic 422 also has a data input connection to data bus 27. Address check logic 422 is a 1-bit memory chip having 256 addressable locations Each of these locations is addressable by a data word transmitted over data bus 27, or by a data word transmitted over data channel 421. The data word transmitted over data bus 27 is derived from computer 20, and is typically gated into address check logic 422 during the initial setup of the system to prepare it for monitoring. Each of the 256 memory locations is representative of a potential equipment address of interest, and during the initial setup of the system for monitoring computer 20 generates a signal over data bus 27 to store a "1" logic bit in each of the memory addresses in address check logic 422 which correspond to the equipment addresses to be monitored. Similarly, condition check logic 424 is accessible by external signals (not shown) to generate predetermined check conditions or error conditions which are to be examined during the monitoring process. At the time the contents of input register 416 are gated into address check logic 422 and condition check logic 424, both the address check logic 422 and the condition check logic 424 generate signals if the data includes address and condition information of the type which the system has been directed to monitor. Address check logic 422 and condition check logic 424 generate a 3-bit signal as a result of this check, and transmit this signal via lines 425 to intermediate register 414. This 3-bit information word is carried by intermediate register 414, which also receives the contents of input register 416 at the same time. The signals from address check logic 422 and condition check logic 424 are also transmitted to presample logic 428 via lines 429, and to postsample logic 430 via lines 431.
Intermediate register 414 receives the contents of input register 416 over data bus 419 at time (c'), together with the 3-bit data word over lines 425 from address check logic 422 and condition check logic 424. Intermediate register 414 transmits its entire contents via data bus 423 to FIFO register bank 412 at time (e'). FIFO register bank 412 consists of sixteen parallel shift registers, each of which have a capacity sufficient to hold the contents of intermediate register 414, including the 3-bit data word which also is held within intermediate register 414. The sixteen registers in FIFO register bank 412 include a first register connected to data bus 423 for receiving information from intermediate register 414, fourteen sequential shift registers for transferring the data in a step-by-step fashion throughout register bank 412, and a final output register which transmits the data via data bus 27 to large store memory 28. Alternatively, the contents of the output register of FIFO register bank 412 may be inhibited from transfer to large store memory 28, in which case the contents of the output register become lost. The decision as to whether the contents of the output register of FIFO register bank 412 are transmitted to large store memory 28 or are simply lost is made as a consequence of the contents of the 3-bit data word generated by address check logic 422 and condition check logic 424. Each time a new data word is received at the first input register of FIFO register bank 412 the contents of all the registers within the register bank are shifted to the adjacent register, and the output register is transmitted either to large store memory 28 or is simply overwritten and lost.
The initiation of a write cycle into large store memory 28 is controlled by LSM write cycle logic 434. Whenever a data word is to be written into large store memory 28 via FIFO register bank 412 LSM write cycle logic 434 generates a signal on line 435. This signal is transmitted to an address counter 518 in system controller 30 to cause large store memory 28 to initiate a write cycle and to transfer the data into storage. At the completion of the memory write cycle large store memory 28 generates a completion signal over line 436 to LSM write cycle logic 434. This signal indicates to LSM write cycle 434 that large store memory 28 is ready to receive a further word transfer.
Large store memory 28 is a commercially available product, as for example, Model PSM 512P, manufactured by Plessey Microsystems, Rockville, Md. Particular logic elements may readily be designed by those skilled in the art to provide the required signals for the proper operation of this memory.
LSM write cycle logic 434 is in turn controlled by signals from a number of sources. A first control signal is received over line 433 from FIFO register bank 412, which signal is dependent upon the contents of the 3-bit data word which was originated in address check logic 422 and condition check logic 424. If this 3-bit data word indicates that the contents of FIFO register bank 412 are to be transferred into large store memory 28, rather than lost, the signal on line 433 will become active, and will initiate an LSM write cycle signal over line 435. A second signal into LSM write cycle logic 434 is received via line 439 from presample logic 428. Presample logic 428 is activated whenever a determination is made by address check logic 422 and condition check logic 424 to save a monitored data word by storing it in large store memory 28, and presample logic 428 determines that a predetermined number of prior samples should also be saved. In the preferred embodiment, presample logic 428 is connected to save fifteen prior samples. These fifteen prior samples are retained in FIFO register bank 412 at the time the sample word of interest is first placed into FIFO register bank 412. Therefore, LSM write cycle 434 will become initiated by a signal on line 439 from presample logic 428 to cause fifteen prior samples to be written into large store memory 28 as a result of detecting a monitored data sample of interest.
Similarly, postsample logic 430 is constructed to cause LSM write cycle 434 to become activated for a predetermined number of postsamples, which occur after the data word sample of interest. In the preferred embodiment postsample logic 430 has been designed to provide fifteen postsamples, which causes LSM write cycle 434 to activate large store memory 28 for receiving fifteen additional words. Postsample logic 430 activates LSM write cycle logic 434 via line 441.
Sample control logic 432 provides a further control over LSM write cycle logic 434 via line 445. Sample control logic 432 provides an overall control of the total number of samples to be taken after a designated error or other condition has been detected by condition check logic 424 and signaled to sample control logic 432 over line 447. Sample control logic 432 receives a signal from computer 20 via line 443, which signal designates the total number of samples to be taken after detecting the predetermined condition. The signal on line 443 is typically generated by computer 20 during the time when initial conditions are set into the system for the sampling operation.
Finally, FIFO preload logic 426 also controls LSM write cycle logic 434 via a signal transmitted over line 427. FIFO preload logic 426 serves to function only during the initial sampling sequences, wherein it causes FIFO register bank 412 to become loaded with fifteen samples in order to set up the FIFO register bank 412 for subsequent operation. The gating of the respective data words through FIFO register bank 412 is controlled by a signal from LSM write cycle logic 434 over line 437. This signal controls the shifting between intermediate register stages within FIFO register bank 412.
In summary, FIFO memory and control 24 operates to receive data samples from cache memory 16. Each of these data samples are examined to determine whether they contain information to be retained in large store memory 28, or whether they may simply be discarded as not containing information of interest. Once a determination is made that a sample should be saved the control logic within FIFO memory and control 24 controls large store memory 28 to not only save the data sample of interest, but also to save the fifteen previous data samples and the fifteen subsequent data samples. The signal timing conditions required for the transfer of data within FIFO memory and control 24 are generated by a timing chain generator 420, and the overall data transfer rates of FIFO memory and control 24 are determined by the speed of the memory cycle for large store memory 28, if the data is to be saved, and by the cycle time of timing chain generator 420 if the data is to be discarded.
All of the registers and logic elements shown in FIG. 4, in connection with FIFO and control 24, are standard commercially available components. The logic functions described above may be readily incorporated by those skilled in the art from combinations of these commercially available components.
SYSTEM CONTROLLER
System controller 30 is illustrated in functional block diagram form in FIG. 5. The components utilized in system controller 30 are commercially available semiconductor components, including registers, counters and logic elements. System controller 30 has an interface adapted for connection to computer bus 21, and for receiving computer data and control signals from computer 20. Likewise, system controller 30 has an interface adapted for connection to data bus 27, for transmitting signals to channel interface 10 and FIFO 24. Computer bus interface 510 is connected via an internal data path 514 to data bus interface 512. Computer bus interface 510 is also connected via an internal data path 515 to an address register 520. Address register 520 is in turn connected to large store memory 28 via address bus 521. An address counter 518 is also connected to address register 520. Address counter 518 has a count capacity sufficient to address all of the memory locations in large store memory 28, and the count value in address counter 518 is incrementally advanced by a signal on LSM write cycle line 435.
Control logic 516 generates control signals over lines 525 and 527 for controlling the data transfer capabilities of data bus interface 512 and computer bus interface 510. Control logic 516 in turn is driven by control signals over lines 523, which are derived from computer 20.
System controller 30 is in large part an internal switching network which is controllable by computer 20 to provide data channel signal paths for the several modes of possible operation of the system. For example, computer 20 may generate control signals over lines 523 to cause control logic 516 to link the data bus interface 512 directly to the computer bus interface 510. In this mode, computer 20 becomes directly coupled for data transfer to either the channel interface 10 or the FIFO 24. As a further example, computer 20 may generate control signals over lines 523 to control logic 516 to cause computer 20 to directly interact with large store memory 28. In this mode, computer bus interface 510 is linked via internal data path 515 directly to large store memory address register 520. Computer 20 can then generate an address to large store memory 28 via address bus 521. As data is retrieved from large store memory 28 over data bus 27, data bus interface 27 causes this data to be transferred directly to computer bus interface 510, and thereafter to computer 20 via computer bus 21. As a further example, computer 20 may generate control signals over lines 523 to cause control logic 516 to generate control signals to permit data bus interface 27 and address counter 518 to control the operation of large store memory 28. In this mode, large store memory 28 is adapted to receive data from FIFO 24, in consecutive memory locations which are determined by address counter 518, address counter 518 being incrementally advanced by ISM write cycle signals present on line 435.
Signals generated by computer 20 over lines 523 may also cause control logic 516 to release data bus 27 so that a tape control unit (not shown) can exercise control of data bus 27 to effect a direct large store memory to tape unit transfer.
COMPUTER
Computer 20 may be selected from a number of commercially available computers, and in the preferred embodiment a Model MC85 Single Board Computer available from Comark Corporation, Medfield, Mass., has been selected. This computer has an internal random access memory, with a memory expansion capability to enable it to store up to 20,000 bytes of information in 8-bit words. The computer has 48 programmable parallel input/output (I/O) lines, programmable priority interrupts, programmable interval timers and an internal controller for operating display 36 The computer is designed to operate at a system clock time of 5 megahertz, and it has a 16-bit address bus which allows it to directly address up to 64,000 bytes of memory. The computer is fully described in a booklet published by Comark Corporation entitled "Users Manual", and is published under Document No. D-05-00780-001, Revision B.
CHANNEL MONITORING
While the invention may be utilized for monitoring signals in computer systems and digital communication systems of a wide variety of types, the preferred embodiment is best understood in connection with the communications conventions adopted by International Business Machines (IBM). In particular, the IBM System/360 and System/370 input/output interface channel conventions are widely known in the art, and is described in IBM Publication GA22-6974-7, and reference will be made herein to these conventions in connection with the operation of the invention.
FIG. 6 shows a diagram of the input/output (I/O) lines in a conventional interface channel for connecting control units to a computer channel. The channel typically utilizes a total of 35-bits, divided into an 18-bit segment associated with data transmitted over the channel, and a 17-bit segment associated with control information relating to the data. The data segment of the channel word is further subdivided into a 9-bit segment associated with input data to the computer, comprising one data byte plus a parity bit, and a 9-bit segment associated with output data from the computer, comprising a data byte plus a parity bit. The control segment is further subdivided into an 8-bit input control segment and a 9-bit output control segment.
The data input lines are used to transmit information, including actual data, selected I/O-device addresses, status information, and sense information from a control unit to the channel. The output data lines are used to transmit data, I/O-device address information, commands, and control information from the channel to the control unit. The control segment of the 35-bit word may be further subdivided and defined as containing four input control and four output control "tag" lines, which are used for interlocking and controlling information on the channel and for special sequences. The control segment of the 35-bit word may be further described in terms of five input and four output selection/control lines, which are used for scanning or selection of attached I/O devices, and for providing special control conditions. These subdivisions are illustrated in FIG. 6.
The control segment of the interface channel lines are conveniently referred to in mnemonic form, which are described below:
______________________________________ADI ADDRESS IN ADO ADDRESS OUTSTI STATUS IN CDO COMMAND OUTSVI SERVICE IN SVO SERVICE OUTDTI DATA IN DTO DATA OUTOPI OPERATIONAL IN OPO OPERATIONAL OUTSLI SELECT IN SLO SELECT OUTRQI REQUEST IN HLO HOLD OUTDII DISCONNECT IN SPO SUPRESS OUTMOI MARK ZERO IN______________________________________
Each of the foregoing mneumonic signal descriptors has a well-defined meaning and use in connection with information control and transfer in computer interface channels. The present invention may be connected to each of the foregoing lines through input lines 12 which terminate at channel interface 10.
The preferred embodiment of the present invention also provides ten additional input lines 14 which may be selectively connected to other equipment signal points of interest to enable the operator to utilize these additional lines to control or predetermine the selection of sample data of interest. In any event, once the predetermined conditions for sampling have been met the entire set of signals represented by FIG. 6 will be received by channel interface 10 in the form of forty-five discrete signals, and will be transferred through the cache memory 16 and FIFO 24 for ultimate storage in large store memory 28. The information may subsequently be retrieved from large store memory 28 by means of transfers controlled by computer 20, and the information may be organized by computer 20 for meaningful presentation to an operator on display 36, in a manner to be hereinafter described. Although many forms of visualization of the information are possible, it is a novel feature and advantage of the present invention to provide a preferred form of visualization to enable an operator to quickly and conveniently analyze the activities being monitored.
SYSTEM OPERATION--INITIALIZATION
The operation of the invention is controlled primarily through the software programs which are prestored in computer 20, which are organized into functional groupings according to several different operational sequences. The programs are adapted to utilize the visual display 36 to interact with an operator, and a keyboard 22 to receive overall system direction and control from an operator. A first functional group of operating programs is related to the setting up of the necessary sampling conditions prior to beginning an actual sampling run. In this regard, the operator may utilize keyboard 22 to key the addresses of interest into computer 20. The addresses of interest are designated by equipment address quantities associated with the equipment being monitored, to cause the system to sample information associated with this equipment if its address is designated. Further, the operator may designate via keyboard 22 specific signal lines of interest, and may cause the system to begin sampling whenever the designated signal lines change signal state from high to low or vice versa. Signal lines of interest may include control lines between equipment of interest being monitored, which indicate that a particular piece of equipment is being activated or deactivated, or may include particular channel data lines of interest. Further, the operator may designate via keyboard 22 the start and stop conditions for a sampling run, such as starting the sampling run upon the happening of the activation of certain signal lines, or stopping a sampling run upon the collection of a designated number of samples.
SYSTEM OPERATION--SAMPLE EXECUTION
The operator may designate via keyboard 22 the condition or conditions upon which a sampling run is to be executed. These conditions may be made dependent upon the happening of an external signal condition, or upon the activation of a particular key on keyboard 22. After a sampling run has been executed it will continue until the designated stop conditions have occurred, or alternatively the operator may manually stop a sampling run via a command entered over keyboard 22.
During the time that a sampling run is being executed the channel interface continually monitors the signals to which it is connected, and periodically receives and transmits signal information of interest into cache memory 16. Cache memory 16 in turn forwards the signal information of interest into FIFO 24, and FIFO 24 under the control of system controller 30 transfers the information into large store memory 28. At the completion of a sampling run large store memory 28 will retain all of the collected samples, stored in successive memory locations, including information relating to the origin of the samples and the conditions of various signal lines which cause the sample to be taken. In addition, large store memory 28 will retain information sampled on the signal lines of interest prior to the occurrence of the event of interest, and samples of the signal lines subsequent to the occurrence of the signal of interest. This provides information relating to the conditions which existed in the system just prior to the occurrence of the signal of interest, and information on the conditions that existed within the system just after the sampling segment has ended.
SYSTEM OPERATION--RESULTS
At the completion of a sampling run it is typical that large store memory 28 has collected and retained a very significant volume of information and data, which information and data has been sequentially stored in successive memory locations. Because of the high data collection rates and the very large volume of data which is collected it is difficult to meaningfully analyze the data stored in large store memory 28 as a result of a sampling run. One of the novel features of the present invention enables the system to organize and present the data to the operator in a fashion which enables the operator to quickly scan the sampled data, and which directs the operator's attention to signal changes which caused events of interest to occur. This operator interaction is facilitated by computer 20 and display 36, operating in conjunction with large store memory 28. The information displayed on display 36 provides an indication of the changes which occurred from one sample to the next, in addition to an indication of conditions which existed at the time the sample was taken.
The information stored in large store memory 28 includes a binary representation of the data and control bits for each channel word as illustrated in FIG. 6. Each word is stored in the same sequence and order as it was received by channel interface 10, and may therefore be retrieved for presentation to an operator in the same order as it was received. Since the channel data is organized into segments as shown in FIG. 6, it may be presented to an operator on a CRT screen in tabular form, under column headings identifying the same segments. The tabular presentation of the individual segments of data may be made in the identical binary form in which it is found in large store memory 28, or in some other form which is more conveniently read and understood by an operator. For example, the "data in" and "data out" segments may be presented on CRT display 36 as decimal numeral representations of the actual data stored in large store memory 28, or as alphabetic representations thereof, or as hexadecimal representations, or in any other convenient form which is readily understandable by the operator. Similarly, the information represented in the control segment of each word stored in large store memory 28 may be displayed on visual display screen 36 under columnar headings identifying the information as either "Control In" or "Control Out" information. The information may be represented in any convenient form readily understandable by the operator, such as the mneumonic form illustrated in FIG. 6, or in any other convenient representation.
The data stored in large store memory 28 was initially caused to be sampled and saved as a result of signal changes on one or more of the input lines 12 and 14 which are coupled to channel interface 10. Therefore, each word stored in large store memory 28 will have at least 1-bit which is different from the word stored in the preceding memory address, and which is different from the word stored in the next subsequent memory address. These differences in bit configurations represent the signals which were monitored and which initiated the actions causing the information to be collected and stored in large store memory 28. An exception to this rule may be found in connection with the fifteen samples which are inherently captured by the system immediately preceding the sample point of interest and immediately succeeding the previous sample point of interest, for these presample and postsample words may or may not be time-consecutive samples.
When the system operation is placed in the analysis and results mode computer 20 becomes operational to retrieve subsequent memory addresses from large store memory 28, transfer the retrieved information into computer 20 for postprocessing operations, if any, and display the results on display screen 36. A preferred form of visualization of the results is illustrated in FIG. 7, which is representative of a typical display screen organized according to the teachings of the invention. This form of organization has the advantage of presenting to the operator a complete representation of each of the collected samples, and in addition presenting to the operator a display of the signal change which caused the sample to be taken. The tabular information presented under the heading "Sample Number" is merely a numerical sequential value representative of the order in which the samples were taken, corresponding to the relative addresses in large store memory from which the samples were retrieved. Alternatively, the column entitled "Sample No." could be designated as "Sample Interval", and the tabular results in the column could be a time representation of the time interval between a given sample and the next previous sample. The column in FIG. 7 entitled "Bus Out Value" presents a representation of the "Data Out" segment of the words shown in FIG. 6, in a form which is understandable to the operator. In the illustration presented in FIG. 7 the "Bus Out Value" is illustratively shown as two numerical digits indicative of data values. Similarly, the column entitled "Bus In Value" is representative of the data segment of FIG. 6 entitled "Data In".
The column entitled "External Signals" is a tabular representation of the consecutive states of the respective external signal lines 14, displayed in a form which is convenient and understandable to the operator. For purposes of illustration these signal values are shown in FIG. 7 in binary form, although other forms are also appropriately available. The column in FIG. 7 entitled "Changes" shows a sequential tabulation of each of the signal changes which occurred from one sample to the next, and therefore provide a visualization to the operator of the signal conditions within the equipment being monitored which caused the sample to be taken. By sequentially examining the data tabulated in this column the operator can determine the precise sequence of signals which governed the operation of the system being monitored. The column entitled "True Tags" in FIG. 7 provides a representation of the control bit information which is found in the control segment of the channel word illustrated in FIG. 6. For convenience, the visualization shown in FIG. 7 illustrates only those tags which were present on the monitored signal lines at the time the sample was taken, thereby indicating the active signal tags at the time the sample was taken. It should be noted that the column entitled "Changes" illustrates all changes which occurred from one sample to the next, including conditions where signals were applied to the lines as well as conditions where signals were deleted from the lines. The representation provided for signals that are removed from a signal line is to show the signal representation with a slash (/) immediately preceding the signal representation. For example, sample No. 725 shows that the change which occurred was /svi, indicating that the "service in" signal was removed from the signal lines, and that this removed signal caused the sample to be taken. If an operator understands the operating protocol of the equipment being monitored, it is readily apparent from an inspection of the tabular information under the column "Changes" to quickly verify whether the protocol is operationally correct, and if protocol errors are present in the system this inspection will quickly reveal the source of such errors.
In another form of visualization of the results of a sampling operation, the contents of large store memory 28 may be sequentially displayed only in respect of the changes which have occurred from sample to sample, with or without the corresponding data values in existence at each sample time, to provide a simple and rapid examination of all of the sequential signal changes which have occurred during the sampling interval. This form of visualization enables the operator to quickly examine all of the changes which have occurred during the sampling mode, and can enable an operator to check for a known or expected signal change.
In yet another form of visualization of the results of sampling, a real time clock may be connected to one of the input lines 14 to provide a regular and systematic clocking scheme for regulating the sampling intervals. This visualization may enable the operator to obtain statistical information relating to the relative usage of the lines being monitored, for obtaining samples as a function of time rather than as a function of other signal changes.
The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof, and it is therefore desired that the present embodiment be considered in all respects as illustrative and not restrictive, reference being made to the appended claims rather than to the foregoing description to indicate the scope of the invention.
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A method of monitoring signal lines on a computer data channel, and copying the respective data transmissions which occur in time sequence into a memory in space sequence corresponding to the time sequence, includes recognizing particular data channel signals, and includes displaying selected portions of the recorded tabulations of data transmissions, which portions include the data transmissions bounded about the recognized particular data transmission.
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